System for electric energy management

CROSS-REFERENCE TO RELATED APPLICATION

p-0002This application claims the benefit of Korean Patent Application No. 10-2010-0086738 filed Sep. 3, 2010, the disclosure of which is hereby incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

p-00031. Field of the Invention

p-0004An aspect of the present invention relates to a system for electric energy management, and more particularly, to a system for electric energy management, which can monitor presence of occurrence of electricity theft based on information on the quantity of electricity measured by a plurality of watt-hour meters, and notify a manager of the presence of the occurrence of the electricity theft.

p-00052. Description of the Related Art

p-0006It is an important issue to monitor and prevent electricity theft in relation to management of electric energy, and smart meters have recently required the function of monitoring and preventing the electricity theft.

p-0007If the electricity theft occurs, there is a serious risk that a safety accident such as an electric shock or fire may occur. More than anything else, an electric power company is directly affected by the economic loss.

p-0008Therefore, it is required to develop various methods for precisely and effectively monitoring the electricity theft. Particularly, inconvenience should not be caused to honest users that normally use electric energy in the process of monitoring the electricity theft.

SUMMARY OF THE INVENTION

p-0009Embodiments of the present invention provide a system for electric energy management, which can calculate admittance or impedance at each place based on an amount of electricity measured by each watt-hour meter, and precisely determine the presence of electricity theft using the calculated admittances or impedances.

p-0010According to an aspect of the present invention, there is provided a system for electric energy management, the system including: a first watt-hour meter installed at an upper place on an electric power line, which is close to a power source, so as to measure an amount of electricity supplied to a load with respect to a position at which the first watt-hour meter is installed and calculate a first admittance based on the measured amount of electricity; a plurality of second watt-hour meters installed at a lower place on the same electric power line as the first watt-hour meter so as to measure an amount of electricity supplied to a load with respect to a position at which each of the second watt-hour meters is installed and calculates second admittances based on the respective measured amounts of electricity; and a remote server configured to collect information on the amounts of electricity from the first and second watt-hour meters.

p-0011The remote server may collect the information on the admittances respectively calculated by the first and second watt-hour meters, compare the first admittance with the total sum of the second admittances, and determine the presence of electricity theft based on a degree to which the difference between the first admittance and the total sum of the second admittances is deviated from an acceptable range.

p-0012According to another aspect of the present invention, there is provided a system for electric energy management, the system including: a first watt-hour meter installed at an upper place on an electric power line, which is close to a power source, so as to measure an amount of electricity supplied to a load; a plurality of second watt-hour meters installed at a lower place on the same electric power line as the first watt-hour meter; and a remote server configured to collect information on the amounts of electricity from the first and second watt-hour meters.

p-0013In some exemplary embodiments, the remote server may calculate a first admittance based on the information on the amount of electricity collected from the first watt-hour meter, calculate second admittances based on information on the amounts of electricity respectively collected from the second watt-hour meters, compare the calculated first admittance with the total sum of the calculated second admittances, and determine the presence of electricity theft based on a degree to which the difference between the first admittance and the total sum of the second admittances is deviated from an acceptable range.

p-0014In some exemplary embodiments, the admittance may be calculated based on information on amounts of electricity measured at the same time.

p-0015In some exemplary embodiments, the admittance may be calculated based on an accumulated value of amounts of electricity, an instantaneous value of amounts of electricity and a mean value of amounts of electricity for a certain period of time.

p-0016In some exemplary embodiments, the remote server may determine the presence of electricity theft based on a mean value of admittances for a certain period of time.

p-0017In some exemplary embodiments, the remote server may determine the presence of electricity theft based on whether or not the difference value between the first admittance and the total sum of the second admittances is a previously set limit value or more.

p-0018In some exemplary embodiments, the remote server may determine the presence of electricity theft based on the fluctuation in the difference value between the first admittance and the total sum of the second admittances.

p-0019According to still another aspect of the present invention, there is provided a system for electric energy management, the system including: a first watt-hour meter installed at an upper place on an electric power line, which is close to a power source, so as to measure an amount of electricity supplied to a load with respect to a position at which the first watt-hour meter is installed and calculate a first impedance based on the measured amount of electricity; a plurality of second watt-hour meters installed at a lower place on the same electric power line as the first watt-hour meter so as to measure an amount of electricity supplied to a load with respect to a position at which each of the second watt-hour meters is installed and calculates second impedances based on the respective measured amounts of electricity; and a remote server configured to collect information on the amounts of electricity from the first and second watt-hour meters.

p-0020In some exemplary embodiments, the remote server may collect the information on the impedances respectively calculated by the first and second watt-hour meters, compare the first impedance with the equivalent of the second impedances, and determine the presence of electricity theft based on a degree to which the difference between the first impedance and the equivalent value of the second impedances is deviated from an acceptable range.

p-0021According to still another aspect of the present invention, there is provided a system for electric energy management, the system including: a first watt-hour meter installed at an upper place on an electric power line, which is close to a power source, so as to measure an amount of electricity supplied to a load; a plurality of second watt-hour meters installed at a lower place on the same electric power line as the first watt-hour meter; and a remote server configured to collect information on the amounts of electricity from the first and second watt-hour meters.

p-0022In some exemplary embodiments, the remote server may calculate a first impedance based on the information on the amount of electricity collected from the first watt-hour meter, calculate second impedances based on information on the amounts of electricity respectively collected from the second watt-hour meters, compare the calculated first impedance with the equivalent value of the calculated second impedances, and determine the presence of electricity theft based on a degree to which the difference between the first impedance and the equivalent value of the second impedances is deviated from an acceptable range.

p-0023In some exemplary embodiments, the impedance may be calculated based on information on amounts of electricity measured at the same time.

p-0024In some exemplary embodiments, the impedance may be calculated based on an accumulated value of amounts of electricity, an instantaneous value of amounts of electricity and a mean value of amounts of electricity for a certain period of time.

p-0025In some exemplary embodiments, the remote server may determine the presence of electricity theft based on a mean value of impedances for a certain period of time.

p-0026In some exemplary embodiments, the remote server may determine the presence of electricity theft based on whether difference value between the first impedance and the equivalent value of the second impedances is a previously set limit value or more.

p-0027In some exemplary embodiments, the remote server may determine the presence of electricity theft based on the fluctuation in the difference value between the first impedance and the equivalent value of the second impedances.

p-0028In some exemplary embodiments, when it is determined that electricity theft has occurred, the remote server may notify a manager of the occurrence of the electricity theft. The remote server may periodically determine the presence of the electricity theft at a predetermined time

p-0029In some exemplary embodiments, the acceptable range may be set by the manager.

p-0030In some exemplary embodiments, the acceptable range may include an error of the amounts of electricity measured by the first and second watt-hour meters.

p-0031In some exemplary embodiments, the acceptable range may include an error generated due to the amount of electricity lost in electric equipment between the first and second watt-hour meters.

BRIEF DESCRIPTION OF THE DRAWINGS

p-0032These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

p-0033<figref idrefs="DRAWINGS">FIG. 1</figref> shows an embodiment of a system for electric energy management according to the present invention;

p-0034<figref idrefs="DRAWINGS">FIG. 2</figref> shows an example in which first and second watt-hour meters individually transmit information necessary for determining the presence of electricity theft to a remote server;

p-0035<figref idrefs="DRAWINGS">FIG. 3</figref> shows an example in which the first watt-hour meter collects information necessary for determining the presence of electricity theft from the second watt-hour meters and transmits the collected information to the remote server;

p-0036<figref idrefs="DRAWINGS">FIGS. 4 and 5</figref> show an example for illustrating a method in which the remote server determines the presence of electricity theft using admittance;

p-0037<figref idrefs="DRAWINGS">FIGS. 6 and 7</figref> show an example for illustrating a method in which the remote server determines the presence of electricity theft using impedance;

p-0038<figref idrefs="DRAWINGS">FIG. 8</figref> schematically shows an embodiment in which the remote server informs a manager of the presence of electricity theft;

p-0039<figref idrefs="DRAWINGS">FIG. 9</figref> shows an example of a functional block diagram of a system for electric energy management;

p-0040<figref idrefs="DRAWINGS">FIGS. 10 and 11</figref> shows an example of a process in which a system for electric energy management operates according to a first embodiment of the present invention;

p-0041<figref idrefs="DRAWINGS">FIGS. 12 and 13</figref> shows an example of a process in which a system for electric energy management operates according to a second embodiment of the present invention;

p-0042<figref idrefs="DRAWINGS">FIGS. 14 and 15</figref> shows an example of a process in which a system for electric energy management operates according to a third embodiment of the present invention; and

p-0043<figref idrefs="DRAWINGS">FIGS. 16 and 17</figref> shows an example of a process in which a system for electric energy management operates according to a fourth embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

p-0044The present invention is described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the present invention are shown. This present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure is thorough, and will fully convey the scope of the present invention to those skilled in the art.

p-0045<figref idrefs="DRAWINGS">FIG. 1</figref> shows an embodiment of a system for electric energy management according to the present invention. An electric power company <b>11</b> supplies electric energy through an electric power line <b>13</b>, and a first watt-hour meter <b>21</b> and a plurality of second watt-hour meter <b>23</b> are installed in the electric power line <b>13</b>.

p-0046The first and second watt-hour meters <b>21</b> and <b>23</b> are installed at places on the same electric power line <b>13</b>, respectively. The first watt-hour meter <b>21</b> is installed at an upper place on the electric power line <b>13</b>, and the second watt-hour meter <b>21</b> are installed at a lower position on the electric power line <b>13</b>.

p-0047Here, it should be noted that the upper and lower places are relative concepts.

p-0048For example, when the amount of power measured by a watt-hour meter A is the total amount of power measured by a plurality of watt-hour meters B, the position of the watt-hour meter A becomes an upper place, and the position of each of the watt-hour meters B becomes a lower place.

p-0049That is, in the case of a shared accommodation, such as an apartment building, composed of a plurality of households, the first watt-hour meter <b>21</b> may be installed in a place at which the electric power line <b>13</b> enters into the corresponding shared accommodation, a watt-hour meter installed in each of the household may perform the function of the second watt-hour meter <b>23</b>.

p-0050The first watt-hour meter <b>21</b> may be installed at a place, such as a telegraph post, branched into the plurality of the households, and the watt-hour meter of each of the households connected to an electric power line branched from the telegraph post may perform the function of the second watt-hour meter <b>23</b>.

p-0051The system according to the present invention includes a first watt-hour meter <b>21</b>, a plurality of second watt-hour meters and a remote server <b>25</b>.

p-0052Each of the first and second watt-hour meters <b>21</b> and <b>23</b> basically measures the amount of electricity supplied to a load based on its own installation position.

p-0053The ‘amount of electricity’ in relation to the present invention refers to the whole information related to electric energy, which can be used in the calculation of admittance or impedance, in spite of its dictionary meaning.

p-0054As a specific example, the amount of electricity measured by the first and second watt-hour meters <b>21</b> and <b>23</b> may be a passive power amount (VA-hour), active power amount (Watt-hour), voltage integrated amount (V²-hour) or current integrated amount (I²-hour), which is an integrated value, an apparent power (VA), effective power (Watt), voltage effective power (V_rms) or current effective power (I_rms), which is an instantaneous value, or a mean value of these values.

p-0055The remote server <b>25</b> collects information necessary for determining the presence of electricity theft from the first and second watt-hour meters <b>21</b> and <b>23</b> through a communication network <b>15</b>, and determines the presence of electricity theft using the collected information.

p-0056The communication network <b>15</b> may include various kinds of networks.

p-0057For example, the communication network <b>15</b> may include a power line communication (PLC) network, an Internet network, a code division multiple access (CDMA) network, a personal communication service (PCS) network, a personal handyphone system (PHS) network, a wireless broadband Internet (Wibro) network, and the like.

p-0058The first and second watt-hour meters <b>21</b> and <b>23</b> may transmit information necessary for determining the presence of electricity theft through several paths.

p-0059That is, as shown in the example of <figref idrefs="DRAWINGS">FIG. 2</figref>, the first and second watt-hour meters <b>21</b> and <b>23</b> may individually transmit the information necessary for determining the presence of electricity theft to the remote server <b>25</b>.

p-0060As shown in the example of <figref idrefs="DRAWINGS">FIG. 3</figref>, the second watt-hour meters <b>23</b> may transmit information necessary for determining the presence of electricity theft to the first watt-hour meter <b>21</b>, and the first watt-hour meter <b>12</b> may collect the information necessary for determining the presence of electricity theft from the second watt-hour meters <b>23</b> and then transmit the collected information together with its own information to the remote server <b>25</b>. In this instance, the first and second watt-hour meters <b>21</b> and <b>23</b> may communicated with each other using various wired/wireless communication schemes.

p-0061Meanwhile, the system according to the present invention may be variously configured according to the kind of information that the first and second watt-hour meters <b>21</b> and <b>23</b> transmit to the remote server <b>25</b>, and whether the remote server <b>25</b> uses admittance or impedance so as to determine the presence of electricity theft.

p-0062The admittance or impedance is calculated based on the amount of electricity measured by the first and second watt-hour meters <b>21</b> and <b>23</b>.

p-0063For convenience of illustration, the admittance and impedance calculated from the amount of electricity measured by the first watt-hour meter <b>21</b> are referred to as a first admittance and a first impedance, respectively. The admittance and impedance calculated from the amount of electricity measured by the second watt-hour meter <b>23</b> are referred to as a second admittance and a second impedance, respectively.

p-0064Since there exist a plurality of second watt-hour meters <b>23</b>, there exist a plurality of second admittances or a plurality of second impedances.

p-0065Various embodiments of the system according to the present invention will now be described in detail.

First Embodiment

p-0066The first embodiment of the system according to the present invention is configured so that each of the first and second watt-hour meters <b>21</b> and <b>23</b> calculates admittance by itself. The remote server <b>25</b> collects information on a first admittance and information on second admittances through the communication network <b>15</b>, and determines the presence of electricity theft based on the information.

p-0067Each of the first and second watt-hour meters <b>21</b> and <b>23</b> measures an amount of electricity supplied to a load based on its own installation position, and calculates admittance based on the measured amount of electricity.

p-0068Each of the first and second watt-hour meters <b>21</b> and <b>23</b> may calculate admittance using the integrated, instantaneous or mean value of various amounts of electricity. Various examples for calculating admittance are represented by expressions 1 to 10.

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width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>of</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mrow><mi>voltage</mi><mo>[</mo><mrow><msup><mi>V</mi><mn>2</mn></msup><mo>-</mo><mi>hour</mi></mrow><mo>]</mo></mrow></mrow></mtd></mtr></mtable></mfrac></msqrt></mrow></mtd><mtd><mrow><mo>[</mo><mrow><mi>Expression</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mn>5</mn></mrow><mo>]</mo></mrow></mtd></mtr><mtr><mtd><mrow><mi>Y</mi><mo>=</mo><mfrac><mrow><mi>apparent</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mrow><mi>power</mi><mo></mo><mrow><mo>[</mo><mi>VA</mi><mo>]</mo></mrow></mrow></mrow><mrow><mi>square</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>of</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>effective</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>value</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>of</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mrow><mi>voltage</mi><mo></mo><mrow><mo>[</mo><msubsup><mi>V</mi><mi>rms</mi><mn>2</mn></msubsup><mo>]</mo></mrow></mrow></mrow></mfrac></mrow></mtd><mtd><mrow><mo>[</mo><mrow><mi>Expression</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mn>6</mn></mrow><mo>]</mo></mrow></mtd></mtr><mtr><mtd><mrow><mi>Y</mi><mo>=</mo><mfrac><mrow><mi>active</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mrow><mi>power</mi><mo></mo><mrow><mo>[</mo><mi>Watt</mi><mo>]</mo></mrow></mrow></mrow><mrow><mi>square</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>of</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>effective</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>value</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>of</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mrow><mi>voltage</mi><mo></mo><mrow><mo>[</mo><msubsup><mi>V</mi><mi>rms</mi><mn>2</mn></msubsup><mo>]</mo></mrow></mrow></mrow></mfrac></mrow></mtd><mtd><mrow><mo>[</mo><mrow><mi>Expression</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mn>7</mn></mrow><mo>]</mo></mrow></mtd></mtr><mtr><mtd><mrow><mi>Y</mi><mo>=</mo><mfrac><mrow><mi>square</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>of</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>effective</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>value</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>of</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mrow><mi>current</mi><mo></mo><mrow><mo>[</mo><msubsup><mi>I</mi><mi>rms</mi><mn>2</mn></msubsup><mo>]</mo></mrow></mrow></mrow><mrow><mi>apparent</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mrow><mi>power</mi><mo></mo><mrow><mo>[</mo><mi>VA</mi><mo>]</mo></mrow></mrow></mrow></mfrac></mrow></mtd><mtd><mrow><mo>[</mo><mrow><mi>Expression</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mn>8</mn></mrow><mo>]</mo></mrow></mtd></mtr><mtr><mtd><mrow><mi>Y</mi><mo>=</mo><mfrac><mrow><mi>square</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>of</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>effective</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>value</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>of</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mrow><mi>current</mi><mo></mo><mrow><mo>[</mo><msubsup><mi>I</mi><mi>rms</mi><mn>2</mn></msubsup><mo>]</mo></mrow></mrow></mrow><mrow><mi>active</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mrow><mi>power</mi><mo></mo><mrow><mo>[</mo><mi>Watt</mi><mo>]</mo></mrow></mrow></mrow></mfrac></mrow></mtd><mtd><mrow><mo>[</mo><mrow><mi>Expression</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mn>9</mn></mrow><mo>]</mo></mrow></mtd></mtr><mtr><mtd><mrow><mi>Y</mi><mo>=</mo><mfrac><mrow><mi>effective</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>value</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>of</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mrow><mi>current</mi><mo></mo><mrow><mo>[</mo><msub><mi>I</mi><mi>rms</mi></msub><mo>]</mo></mrow></mrow></mrow><mrow><mi>effective</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>value</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mi>of</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mrow><mi>voltage</mi><mo></mo><mrow><mo>[</mo><msub><mi>V</mi><mi>rms</mi></msub><mo>]</mo></mrow></mrow></mrow></mfrac></mrow></mtd><mtd><mrow><mo>[</mo><mrow><mi>Expression</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mn>10</mn></mrow><mo>]</mo></mrow></mtd></mtr></mtable></math></maths>

p-0070In the expressions 1 to 10, ‘Y’ denotes admittance, the expressions 2, 4, 7 and 9 may be used only when the power factors of the first and second watt-hour meters <b>21</b> and <b>23</b> are identical to each other.

p-0071As shown in the example of <figref idrefs="DRAWINGS">FIG. 2</figref>, the first and second watt-hour meters <b>21</b> and <b>23</b> may individually transmit information on the calculated admittance to the remote server <b>25</b> through the communication network <b>15</b>. Alternately, as shown in the example of <figref idrefs="DRAWINGS">FIG. 3</figref>, the first watt-hour meter <b>21</b> may collect information on the admittances respectively calculated by the second watt-hour meters <b>23</b> and transmit the information together with the information on its own calculated admittance to the remote server <b>25</b> through the communication network <b>15</b>.

p-0072The remote server <b>25</b> receives information on a first admittance calculated by the first watt-hour meter <b>21</b> and information on second admittances respectively calculated by the second watt-hour meters <b>23</b>, and compares the first admittance with the total sum of the second admittances. Then, the remote server <b>25</b> determines the presence of occurrence of electricity theft based on a degree to which the difference between the first admittance and the total sum of the second admittances is deviated from an acceptable range.

p-0073That is, theoretically, the total sum of the second admittances necessarily corresponds to the first admittance. Therefore, if the difference value between the first admittance and the total sum of the second admittances is deviated from the acceptable range, it may be determined that electricity theft is made at anywhere of lower place at which the first watt-hour meter <b>21</b> is installed.

p-0074Accordingly, the first and second admittances are necessarily calculated based on information on the amount of electricity at the same time.

p-0075For example, if admittance is calculated using the amount of instantaneous electricity, the first and second watt-hour meters <b>21</b> and <b>23</b> necessarily calculate the respective admittances based on information on amounts of electricity measured at the same time (e.g., just at 6 and 18 o'clock everyday).

p-0076If admittance is calculated using the amount of accumulated electricity, the first and second watt-hour meters <b>21</b> and <b>23</b> necessarily calculate the respective admittances based on information on amounts of electricity accumulated during the same period (e.g., from 12 o'clock, first January, 2010 to the present).

p-0077The acceptable range may be variously set as occasion demands. Particularly, the first and second watt-hour meters <b>21</b> and <b>23</b> measure the amount of electricity, the acceptable range is preferably set in consideration of a measurement error that may occur even in a normal situation. The acceptable range may include an error that occurs because of the amount of electricity lost in electric equipment between the first and second watt-hour meters <b>21</b> and <b>23</b>.

p-0078The acceptable range may be previously set by the remote server, or may be configured to be set by a manager.

p-0079In the latter example, the remote sever <b>25</b> may provide a user interface (UI) that enables the manager to set the acceptable range, or may receive an acceptable range set by the manager from another device.

p-0080As described above, the first and second admittances may be changed due to an error of the amount of electricity measured by the first and second watt-hour meters <b>21</b> and <b>23</b> even in a normal situation.

p-0081Therefore, the remote server <b>25</b> may determine the presence of electricity theft using mean values of the first and second admittances received for a certain period of time.

p-0082A method in which the remote server <b>25</b> determines the presence of occurrence of electricity theft will be described in detail with reference to <figref idrefs="DRAWINGS">FIGS. 4 and 5</figref>.

p-0083First, the remote server <b>25</b> calculates a difference value between a first admittance and the total sum of second admittances (S<b>311</b>-<b>1</b>). If it is assumed that the difference value is ‘Y(diff)’, the Y(diff) may be calculated using the following expression 11.

p-0084<maths id="MATH-US-00002" num="00002"><math overflow="scroll"><mtable><mtr><mtd><mrow><mrow><mi>Y</mi><mo></mo><mrow><mo>(</mo><mi>diff</mi><mo>)</mo></mrow></mrow><mo>=</mo><mrow><mo></mo><mrow><mrow><mi>Y</mi><mo></mo><mstyle><mspace width="0.3em" height="0.3ex" /></mstyle><mo></mo><mn>1</mn></mrow><mo>-</mo><mrow><munderover><mo>∑</mo><mrow><mi>i</mi><mo>=</mo><mn>1</mn></mrow><mi>n</mi></munderover><mo></mo><mrow><mi>Y</mi><mo></mo><mstyle><mspace width="0.3em" height="0.3ex" /></mstyle><mo></mo><mn>2</mn><mo></mo><mrow><mo>(</mo><mi>i</mi><mo>)</mo></mrow></mrow></mrow></mrow><mo></mo></mrow></mrow></mtd><mtd><mrow><mo>[</mo><mrow><mi>Expression</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mn>11</mn></mrow><mo>]</mo></mrow></mtd></mtr></mtable></math></maths>

p-0085Here, Y1 denotes a first admittance, Y2(i) denotes a second admittance calculated by an i-th second watt-hour meter, and n denotes a number of second watt-hour meters.

p-0086If the Y(diff) is calculated as described above, the remote server <b>25</b> examines whether or not the Y(diff) is deviated from a previously set acceptable range (S<b>311</b>-<b>2</b>).

p-0087If it is examined that the Y(diff) is deviated from the acceptable range, the remote server <b>25</b> determines that electricity theft has occurred (S<b>311</b>-<b>3</b>). Otherwise, the remote server <b>25</b> determines that no electricity theft has occurred (normal state) (S<b>311</b>-<b>4</b>).

p-0088In this instance, the acceptable range may be set to a constant limit value as shown in the example of <figref idrefs="DRAWINGS">FIG. 5A</figref>. When the Y(diff) is the limit value or more, the remote server <b>25</b> determines that electricity theft has occurred. When the Y(diff) is less than the limit value, the remote server <b>25</b> determines that no electricity theft has occurred (normal state).

p-0089The remote server <b>25</b> may determine the presence of electricity theft according to the fluctuation in the Y(diff) as shown in the example of <figref idrefs="DRAWINGS">FIG. 5B</figref>.

p-0090That is, the Y(diff) may be fluctuated due to an error of the amount of electricity measured by the first and second watt-hour meters <b>21</b> and <b>23</b> even in a normal situation, but the variation width is maintained within a certain acceptable range. However, if electricity theft occurs, the Y(diff) will be deviated from the acceptable range and considerably fluctuated. Therefore, if the Y(diff) is deviated from the acceptable range according to the fluctuation in the Y(diff), the remote server <b>25</b> can determine that the electricity theft has occurred.

Second Embodiment

p-0091The second embodiment of the system according to the present invention is configured so that the remote server <b>25</b> calculates first and second admittances by itself using information on amounts of electricity measured by the first and second watt-hour meters <b>21</b> and <b>23</b> and then determines the presence of electricity theft.

p-0092Each of the first and second watt-hour meters <b>21</b> and <b>23</b> measures an amount of electricity supplied to a load based on its own installation position.

p-0093As shown in the example of <figref idrefs="DRAWINGS">FIG. 2</figref>, the first and second watt-hour meters <b>21</b> and <b>23</b> may individually transmit the information on the measured amount of electricity to the remote server <b>25</b> through the communication network <b>15</b>. Alternately, as shown in the example of <figref idrefs="DRAWINGS">FIG. 3</figref>, the first watt-hour meter <b>21</b> may collect the information on amounts of electricity, respectively measured by the second watt-hour meters <b>23</b> and transmit the information together with the information on its own measured amount of electricity to the remote server <b>25</b> through the communication network <b>15</b>.

p-0094The remote server <b>25</b> calculates first and second admittances by various methods as shown in examples of the expressions 1 to 10, using information on the amount of electricity measured by the first and second watt-hour meters <b>21</b> and <b>23</b>.

p-0095The remote server <b>25</b> compares the calculated first admittance with the total sum of the calculated second admittances, and determines the presence of occurrence of electricity theft based on a degree to which the difference between the first admittance and the total sum of the second admittances is deviated from an acceptable range.

p-0096That is, theoretically, the total sum of the second admittances necessarily corresponds to the first admittance. Therefore, if the difference value between the first admittance and the total sum of the second admittances is deviated from the acceptable range, it may be determined that electricity theft is made at anywhere of lower place at which the first watt-hour meter <b>21</b> is installed.

p-0097Accordingly, the first and second watt-hour meters <b>21</b> and <b>23</b> necessarily transmit the respective amounts of electricity measured based on information on the amount of electricity at the same time.

p-0098For example, if the amount of instantaneous electricity is measured, the first and second watt-hour meters <b>21</b> and <b>23</b> necessarily measure the respective amount of electricity at the same time (e.g., just at 6 and 18 o'clock everyday). If the amount of electricity accumulated for a certain period of time is measured, the first and second watt-hour meters <b>21</b> and <b>23</b> necessarily measure the respective amounts of electricity accumulated during the same period (e.g., from 12 o'clock, first January, 2010 to the present).

p-0099The acceptable range may be variously set as occasion demands. Particularly, the first and second watt-hour meters <b>21</b> and <b>23</b> measure the amount of electricity, the acceptable range is preferably set in consideration of a measurement error that may occur even in a normal situation. The acceptable range may include an error that occurs because of the amount of electricity lost in electric equipment between the first and second watt-hour meters <b>21</b> and <b>23</b>.

p-0100The acceptable range may be previously set by the remote server, or may be configured to be set by a manager.

p-0101In the latter example, the remote sever <b>25</b> may provide a UI that enables the manager to set the acceptable range, or may receive an acceptable range set by the manager from another device.

p-0102Since the first and second admittances may be changed due to an error of the amount of electricity measured by the first and second watt-hour meters <b>21</b> and <b>23</b> even in a normal situation, the remote server <b>25</b> may determine the presence of electricity theft using mean values of the first and second admittances received for a certain period of time.

p-0103After calculating the first and second admittances, the remote server <b>25</b> may determine the presence of electricity theft as described with reference to <figref idrefs="DRAWINGS">FIGS. 4 and 5</figref>.

p-0104That is, as shown in the example of <figref idrefs="DRAWINGS">FIG. 5A</figref>, the remote server <b>25</b> may determine the presence of theft according to whether or not the difference value Y(diff) between the first admittance and the total sum of the second admittances is a previously set limit value or more.

p-0105As shown in the example of <figref idrefs="DRAWINGS">FIG. 5B</figref>, the remote server <b>25</b> may determine the presence of electricity theft according to the fluctuation in the difference value Y(diff) between the first admittance and the total sum of the second admittances.

Third Embodiment

p-0106The third embodiment of the system according to the present invention is configured so that each of the first and second watt-hour meters <b>21</b> and <b>23</b> calculates impedance by itself. The remote server <b>25</b> collects information on a first impedance and information on second impedances through the communication network <b>15</b> and then determines the presence of electricity theft based on the collected information.

p-0107Each of the first and second watt-hour meters <b>21</b> and <b>23</b> measures an amount of electricity supplied to a load based on its own installation position, and calculates impedance based on the measured amount of electricity.

p-0108Each of the first and second watt-hour meters <b>21</b> and <b>23</b> may calculate impedance using the integrated, instantaneous or mean value of various amounts of electricity. The impedance Z may be calculated as a reciprocal number of each of the expressions 1 to 10 as shown in the following expression 12.

p-0109<maths id="MATH-US-00003" num="00003"><math overflow="scroll"><mtable><mtr><mtd><mrow><mi>Z</mi><mo>=</mo><mfrac><mn>1</mn><mi>Y</mi></mfrac></mrow></mtd><mtd><mrow><mo>[</mo><mrow><mi>Expression</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mn>12</mn></mrow><mo>]</mo></mrow></mtd></mtr></mtable></math></maths>

p-0110As shown in the example of <figref idrefs="DRAWINGS">FIG. 2</figref>, the first and second watt-hour meters <b>21</b> and <b>23</b> may individually transmit information on the calculated impedance to the remote server <b>25</b> through the communication network <b>15</b>. Alternately, as shown in the example of <figref idrefs="DRAWINGS">FIG. 3</figref>, the first watt-hour meter <b>21</b> may collect information on the impedances respectively calculated by the second watt-hour meters <b>23</b> and transmit the information together with the information on its own calculated impedance to the remote server <b>25</b> through the communication network <b>15</b>.

p-0111The remote server <b>25</b> receives information on a first impedance calculated by the first watt-hour meter <b>21</b> and information on second impedances respectively calculated by the second watt-hour meters <b>23</b>, and compares the first impedance with the equivalent value of the second impedances. Then, the remote server <b>25</b> determines the presence of occurrence of electricity theft based on a degree to which the difference between the first admittance and the equivalent value of the second admittances is deviated from an acceptable range.

p-0112That is, theoretically, the equivalent value of the second impedances necessarily corresponds to the first impedance. Therefore, if the difference value between the first impedance and the equivalent value of the second impedances is deviated from the acceptable range, it may be determined that electricity theft is made at anywhere of lower place at which the first watt-hour meter <b>21</b> is installed.

p-0113Accordingly, the first and second impedances are necessarily calculated based on based on information on the respective amounts of electricity measured at the same time.

p-0114For example, if impedance is calculated using the amount of instantaneous electricity, the first and second watt-hour meters <b>21</b> and <b>23</b> necessarily calculate the respective impedances based on information on amounts of electricity measured at the same time (e.g., just at 6 and 18 o'clock everyday).

p-0115If impedance is calculated using the amount of accumulated electricity, the first and second watt-hour meters <b>21</b> and <b>23</b> necessarily calculate the respective impedances based on information on amounts of electricity accumulated during the same period (e.g., from 12 o'clock, first January, 2010 to the present).

p-0116The acceptable range may be variously set as occasion demands. Particularly, the first and second watt-hour meters <b>21</b> and <b>23</b> measure the amount of electricity, the acceptable range is preferably set in consideration of a measurement error that may occur even in a normal situation.

p-0117The acceptable range may include an error that occurs because of the amount of electricity lost in electric equipment between the first and second watt-hour meters <b>21</b> and <b>23</b>.

p-0118The acceptable range may be previously set by the remote server, or may be configured to be set by a manager.

p-0119In the latter example, the remote sever <b>25</b> may provide a UI that enables the manager to set the acceptable range, or may receive an acceptable range set by the manager from another device.

p-0120The first and second impedances may be changed due to an error of the amount of electricity measured by the first and second watt-hour meters <b>21</b> and <b>23</b> even in a normal situation.

p-0121Therefore, the remote server <b>25</b> may determine the presence of electricity theft using mean values of the first and second impedances received for a certain period of time.

p-0122A method in which the remote server <b>25</b> determines the presence of the occurrence of electricity theft will be described in detail with reference to <figref idrefs="DRAWINGS">FIGS. 6 and 7</figref>.

p-0123First, the remote server <b>25</b> calculates a difference value between a first impedance and the equivalent value of second admittances (S<b>313</b>-<b>1</b>). If it is assumed that the difference value is ‘Z(diff)’, the Z(diff) may be calculated using the following expression 11.

p-0124<maths id="MATH-US-00004" num="00004"><math overflow="scroll"><mtable><mtr><mtd><mrow><mrow><mi>Z</mi><mo></mo><mrow><mo>(</mo><mi>diff</mi><mo>)</mo></mrow></mrow><mo>=</mo><mrow><mo></mo><mrow><mrow><mi>Z</mi><mo></mo><mstyle><mspace width="0.3em" height="0.3ex" /></mstyle><mo></mo><mn>1</mn></mrow><mo>-</mo><mfrac><mn>1</mn><mrow><munderover><mo>∑</mo><mrow><mi>i</mi><mo>=</mo><mn>1</mn></mrow><mi>n</mi></munderover><mo></mo><mfrac><mn>1</mn><mrow><mi>Z</mi><mo></mo><mstyle><mspace width="0.3em" height="0.3ex" /></mstyle><mo></mo><mn>2</mn><mo></mo><mrow><mo>(</mo><mi>i</mi><mo>)</mo></mrow></mrow></mfrac></mrow></mfrac></mrow><mo></mo></mrow></mrow></mtd><mtd><mrow><mo>[</mo><mrow><mi>Expression</mi><mo></mo><mstyle><mspace width="0.8em" height="0.8ex" /></mstyle><mo></mo><mn>13</mn></mrow><mo>]</mo></mrow></mtd></mtr></mtable></math></maths>

p-0125Here, Z1 denotes a first impedance, Z2(i) denotes a second impedance calculated by an i-th second watt-hour meter, and n denotes a number of second watt-hour meters.

p-0126If the Z(diff) is calculated as described above, the remote server <b>25</b> examines whether or not the Z(diff) is deviated from a previously set acceptable range (S<b>313</b>-<b>2</b>).

p-0127If it is examined that the Z(diff) is deviated from the acceptable range, the remote server <b>25</b> determines that electricity theft has occurred (S<b>313</b>-<b>3</b>). Otherwise, the remote server <b>25</b> determines that no electricity theft has occurred (normal state) (S<b>313</b>-<b>4</b>).

p-0128In this instance, the acceptable range may be set to a constant limit value as shown in the example of <figref idrefs="DRAWINGS">FIG. 7A</figref>. When the Z(diff) is the limit value or more, the remote server <b>25</b> determines that electricity theft has occurred. When the Z(diff) is less than the limit value, the remote server <b>25</b> determines that no electricity theft has occurred (normal state).

p-0129The remote server <b>25</b> may determine the presence of electricity theft according to the fluctuation in the Z(diff).

p-0130That is, the Z(diff) may be fluctuated due to an error of the amount of electricity measured by the first and second watt-hour meters <b>21</b> and <b>23</b> even in a normal situation, but the variation width is maintained within a certain acceptable range. However, if electricity theft occurs, the Z(diff) will be deviated from the acceptable range and considerably fluctuated. Therefore, if the Z(diff) is deviated from the acceptable range according to the fluctuation in the Z(diff), the remote server <b>25</b> can determine that the electricity theft has occurred.

Fourth Embodiment

p-0131The fourth embodiment of the system according to the present invention is configured so that the remote server <b>25</b> calculates first and second impedances by itself using information on amounts of electricity measured by the respective first and second watt-hour meters <b>21</b> and <b>23</b> and then determines the presence of electricity theft.

p-0132Each of the first and second watt-hour meters <b>21</b> and <b>23</b> measures an amount of electricity supplied to a load based on its own installation position.

p-0133As shown in the example of <figref idrefs="DRAWINGS">FIG. 2</figref>, the first and second watt-hour meters <b>21</b> and <b>23</b> may individually transmit the information on the measured amount of electricity to the remote server <b>25</b> through the communication network <b>15</b>. Alternately, as shown in the example of <figref idrefs="DRAWINGS">FIG. 3</figref>, the first watt-hour meter <b>21</b> may collect the information on amounts of electricity, respectively measured by the second watt-hour meters <b>23</b> and transmit the information together with the information on its own measured amount of electricity to the remote server <b>25</b> through the communication network <b>15</b>.

p-0134The remote server <b>25</b> calculates first and second admittances using information on the amount of electricity measured by the first and second watt-hour meters <b>21</b> and <b>23</b>.

p-0135The remote server <b>25</b> compares the calculated first impedance with the equivalent value of the calculated second impedances, and determines the presence of occurrence of electricity theft based on a degree to which the difference between the first impedance and the equivalent value of the second impedances is deviated from an acceptable range.

p-0136That is, theoretically, the equivalent value of the second impedances necessarily corresponds to the first impedance. Therefore, if the difference value between the first impedance and the equivalent value of the second impedances is deviated from the acceptable range, it may be determined that electricity theft is made at anywhere of lower place at which the first watt-hour meter <b>21</b> is installed.

p-0137Accordingly, the first and second watt-hour meters <b>21</b> and <b>23</b> necessarily transmit the respective amounts of electricity measured based on information on the amount of electricity at the same time.

p-0138For example, if the amount of instantaneous electricity is measured, the first and second watt-hour meters <b>21</b> and <b>23</b> necessarily measure the respective amount of electricity at the same time (e.g., just at 6 and 18 o'clock everyday). If the amount of electricity accumulated for a certain period of time is measured, the first and second watt-hour meters <b>21</b> and <b>23</b> necessarily measure the respective amounts of electricity accumulated during the same period (e.g., from 12 o'clock, first January, 2010 to the present).

p-0139The acceptable range may be variously set as occasion demands. Particularly, the first and second watt-hour meters <b>21</b> and <b>23</b> measure the amount of electricity, the acceptable range is preferably set in consideration of a measurement error that may occur even in a normal situation. The acceptable range may include an error that occurs because of the amount of electricity lost in electric equipment between the first and second watt-hour meters <b>21</b> and <b>23</b>.

p-0140The acceptable range may be previously set by the remote server, or may be configured to be set by a manager.

p-0141In the latter example, the remote sever <b>25</b> may provide a UI that enables the manager to set the acceptable range, or may receive an acceptable range set by the manager from another device.

p-0142The first and second impedances may be changed due to an error of the amount of electricity measured by the first and second watt-hour meters <b>21</b> and <b>23</b> even in a normal situation.

p-0143Therefore, the remote server <b>25</b> may determine the presence of electricity theft using mean values of the first and second impedances received for a certain period of time.

p-0144After calculating the first and second impedances, the remote server <b>25</b> may determine the presence of electricity theft as described with reference to <figref idrefs="DRAWINGS">FIGS. 6 and 7</figref>.

p-0145That is, as shown in the example of <figref idrefs="DRAWINGS">FIG. 7A</figref>, the remote server <b>25</b> may determine the presence of theft according to whether or not the difference value Z(diff) between the first impedance and the equivalent of the second impedance is a previously set limit value or more.

p-0146As shown in the example of <figref idrefs="DRAWINGS">FIG. 7B</figref>, the remote server <b>25</b> may determine the presence of electricity theft according to the fluctuation in the difference value Z(diff) between the first impedance and the equivalent value of the second impedances.

p-0147In the system according to the first to fourth embodiments, the remote server <b>25</b> may periodically determine the presence of electricity theft at a predetermined time.

p-0148In the system according to the first to fourth embodiments, when it is determined that electricity theft has occurred as shown in the example of <figref idrefs="DRAWINGS">FIG. 8</figref>, the remote server <b>25</b> may further include a notification component <b>25</b>-<b>4</b> for notifying and warning the manager of the electricity theft.

p-0149The notification component <b>25</b>-<b>4</b> may be configured to notify the manager of the electricity theft using various methods.

p-0150For example, the notification component <b>25</b>-<b>4</b> may display a warning message on a display device such as a monitor screen <b>17</b>-<b>1</b>, or may generate an alarm sound through an alarm device <b>17</b>-<b>2</b>.

p-0151The notification component <b>25</b>-<b>4</b> may transmit a warning message to a manager terminal <b>17</b>-<b>3</b> through various wired/wireless communication networks. For example, the notification component <b>25</b>-<b>4</b> may transmit a warning mail to the manager through an Internet network, or may transmit a warning message to a cellular phone of the manager through a mobile communication network.

p-0152<figref idrefs="DRAWINGS">FIG. 9</figref> shows an example of a functional block diagram of the first watt-hour meter <b>21</b>, the second watt-hour meters and the remote server <b>25</b>.

p-0153The first and second watt-hour meters <b>21</b> and <b>23</b> may include metering components <b>21</b>-<b>1</b> and <b>23</b>-<b>1</b>, storage components <b>21</b>-<b>3</b> and <b>23</b>-<b>3</b>, communication components <b>21</b>-<b>5</b> and <b>23</b>-<b>5</b>, and control components <b>21</b>-<b>7</b> and <b>23</b>-<b>7</b>, respectively.

p-0154Each of the metering components <b>21</b>-<b>1</b> and <b>23</b>-<b>1</b> of the first and second watt-hour meters <b>21</b> and <b>23</b> measures various kinds of information on the amount of electricity at a corresponding place on the electric power line <b>13</b>.

p-0155Each of the storage components <b>21</b>-<b>3</b> and <b>23</b>-<b>3</b> of the first and second watt-hour meters <b>21</b> and <b>23</b> is a nonvolatile storage medium for storing digital data.

p-0156Each of the control components <b>21</b>-<b>7</b> and <b>23</b>-<b>7</b> of the first and second watt-hour meters <b>21</b> and <b>23</b> is configured as a microprocessor, central processing unit (CPU) or the like so as to generally control the watt-hour meter. The control components <b>21</b>-<b>7</b> and <b>23</b>-<b>7</b> of the first and second watt-hour meters <b>21</b> and <b>23</b> store and manage the amounts of electricity measured the metering components <b>21</b>-<b>1</b> and <b>21</b>-<b>3</b> in the storage components <b>21</b>-<b>3</b> and <b>23</b>-<b>3</b>, respectively.

p-0157Each of the control components <b>21</b>-<b>7</b> and <b>23</b>-<b>7</b> of the first and second watt-hour meters <b>21</b> and <b>23</b> communicates with another watt-hour meter or the remote server <b>25</b> through each of the communication components <b>21</b>-<b>5</b> and <b>23</b>-<b>5</b> and transmits information necessary for determining the presence of electricity theft to the watt-hour meter or the remote server <b>25</b>.

p-0158The information necessary for determining the presence of electricity theft may be information on admittance, impedance or the amount of electricity, which is required to calculate the admittance or impedance.

p-0159A communication component <b>25</b>-<b>1</b> of the remote sever <b>25</b> receives information necessary for determining the presence of electricity theft through the communication network <b>15</b>. A storage component <b>25</b>-<b>3</b> of the remote server <b>25</b> is a nonvolatile storage medium, and stores various kinds of information related to the operation of the remote server <b>25</b>.

p-0160A control component <b>25</b>-<b>7</b> of the remote server <b>25</b> may be configured using a CPU, and generally controls the remote server <b>25</b>. Particularly, the control component <b>25</b>-<b>7</b> determines whether or not electricity theft occurs using the information necessary for determining the presence of the electricity theft, received by the communication component <b>25</b>-<b>1</b>.

p-0161A user interface component <b>25</b>-<b>2</b> of the remote server <b>25</b> enables a manager <b>14</b> to input information or command necessary for the operation of the remote server <b>25</b>.

p-0162For example, the manager <b>14</b> may set an acceptable range that becomes a reference for determining the presence of electricity theft through the user interface component <b>25</b>-<b>2</b>, or may set information on a period in which to determine the presence of electricity theft, a cellular phone number of the manager <b>14</b>, to which a warning message is to be transmitted, and the like.

p-0163In a case where it is determined that electricity theft has occurs, the notification component <b>25</b>-<b>4</b> function to inform the manager <b>14</b> of the occurrence of the electricity theft as described with reference to <figref idrefs="DRAWINGS">FIG. 8</figref>.

p-0164The entire process in which the system of each of the embodiments according to the present invention operates will be described with reference to <figref idrefs="DRAWINGS">FIGS. 10</figref> to <b>17</b>. For convenience for illustration, this will be described using the example of the functional block diagram shown in <figref idrefs="DRAWINGS">FIG. 9</figref>.

p-0165<figref idrefs="DRAWINGS">FIG. 10</figref> shows an embodiment in which each of the first and second watt-hour meters <b>21</b> and <b>23</b> individually transmits information on admittance to the remote server <b>25</b> in the system of the first embodiment.

p-0166Each of the metering components <b>21</b>-<b>1</b> and <b>23</b>-<b>1</b> of the first and second watt-hour meters <b>21</b> and <b>23</b> measures an amount of electricity at its own installation position (S<b>411</b>).

p-0167The control component <b>21</b>-<b>7</b> of the first watt-hour meter <b>21</b> calculates a first admittance using information on the amount of electricity measured by the metering component <b>21</b>-<b>1</b>, and each of the control components <b>23</b>-<b>7</b> of the second watt-hour meters <b>23</b> calculates a second admittance using information on the amount of electricity measured by the metering component <b>23</b>-<b>1</b> (S<b>412</b>).

p-0168The control component <b>21</b>-<b>7</b> of the first watt-hour meter <b>21</b> transmits information on the calculated first admittance to the remote server <b>25</b> through the communication component <b>21</b>-<b>5</b>, and each of the control components <b>23</b>-<b>7</b> of the second watt-hour meters <b>23</b> transmits information on the calculated second admittance to the remote server <b>25</b> through the communication component <b>23</b>-<b>5</b> (S<b>413</b>).

p-0169The control component <b>25</b>-<b>7</b> of the remote server <b>25</b> receives the information on the first admittance and the information on the second admittances through the communication component <b>25</b>-<b>1</b>, and determines the presence of occurrence of electricity theft based on the received information (S<b>414</b>).

p-0170In a case where it is determined that electricity theft has occurred, the remote server <b>25</b> notifies the manager <b>14</b> of the occurrence of the electricity theft through the notification component <b>25</b>-<b>4</b> (S<b>415</b> and S<b>416</b>).

p-0171<figref idrefs="DRAWINGS">FIG. 11</figref> shows an embodiment in which the first watt-hour meter <b>21</b> collects information on second admittances respectively calculated by the second watt-hour meters <b>23</b> and transmits the collected information together with information on a first admittance calculated by the first watt-hour meter <b>21</b> to the remote server <b>25</b> in the system of the first embodiment.

p-0172Each of the metering components <b>21</b>-<b>1</b> and <b>23</b>-<b>1</b> of the first and second watt-hour meters <b>21</b> and <b>23</b> measures an amount of electricity at its own installation position (S<b>421</b>).

p-0173The control component <b>21</b>-<b>7</b> of the first watt-hour meter <b>21</b> calculates a first admittance using information on the amount of electricity measured by the metering component <b>21</b>-<b>1</b>, and each of the control components <b>23</b>-<b>7</b> of the second watt-hour meters <b>23</b> calculates a second admittance using information on the amount of electricity measured by the metering component <b>23</b>-<b>1</b> (S<b>422</b>).

p-0174Each of the control components <b>23</b>-<b>7</b> of the second watt-hour meters <b>23</b> transmits information on the calculated second admittance to the first watt-hour meter <b>21</b> through the communication component <b>23</b>-<b>5</b> (S<b>423</b>).

p-0175The control component <b>21</b>-<b>7</b> of the first watt-hour meter <b>21</b> collects the information the second admittances respectively received through the communication components <b>23</b>-<b>5</b> and transmits the collected information together with information on the first admittance calculated by the first watt-hour meter <b>21</b> to the remote server <b>25</b> through the communication component <b>21</b>-<b>5</b> (S<b>424</b>).

p-0176The control component <b>25</b>-<b>7</b> of the remote server <b>25</b> receives the information on the first admittance and the information on the second admittances through the communication component <b>25</b>-<b>1</b>, and determines the presence of occurrence of electricity theft based on the received information (S<b>425</b>).

p-0177In a case where it is determined that electricity theft has occurred, the remote server <b>25</b> notifies the manager <b>14</b> of the occurrence of the electricity theft through the notification component <b>25</b>-<b>4</b> (S<b>426</b> and S<b>427</b>).

p-0178<figref idrefs="DRAWINGS">FIG. 12</figref> shows an embodiment in which each of the first and second watt-hour meters <b>21</b> and <b>23</b> individually transmits information on an amount of electricity to the remote server <b>25</b> in the system of the second embodiment.

p-0179Each of the metering components <b>21</b>-<b>1</b> and <b>23</b>-<b>1</b> of the first and second watt-hour meters <b>21</b> and <b>23</b> measures an amount of electricity at its own installation position (S<b>431</b>).

p-0180The control component <b>21</b>-<b>7</b> of the first watt-hour meter <b>21</b> transmits information on the amount of electricity measured by the metering component <b>21</b>-<b>1</b> to the remote server <b>25</b> through the communication component <b>21</b>-<b>5</b>, and each of the control components <b>23</b>-<b>7</b> of the second watt-hour meters <b>23</b> transmits information on the amount of electricity measured by the metering component <b>23</b>-<b>1</b> to the remote server <b>25</b> through the communication component <b>23</b>-<b>5</b> (S<b>432</b>).

p-0181The control component <b>25</b>-<b>7</b> of the remote server <b>25</b> receives the information on the amounts of electricity respectively measured by the first and second watt-hour meters <b>21</b> and <b>23</b> through the communication component <b>25</b>-<b>1</b>, and calculates first and second admittances using the received information on the amounts of electricity (S<b>433</b>).

p-0182The control component <b>25</b>-<b>7</b> of the remote server <b>25</b> determines the presence of occurrence of electricity theft based on information on the calculated first and second admittances (S<b>434</b>). In a case where it is determined that the electricity theft has occurred, the remote server <b>25</b> notifies the manager <b>14</b> of the occurrence of the electricity theft through the notification component <b>25</b>-<b>4</b> (S<b>435</b> and S<b>436</b>).

p-0183<figref idrefs="DRAWINGS">FIG. 13</figref> shows an embodiment in which the first watt-hour meter <b>21</b> collects information on amounts of electricity respectively measured by the second watt-hour meters <b>23</b> and transmits the collected information together with information on an amount of electricity measured by the first watt-hour meter <b>21</b> to the remote server <b>25</b> in the system of the second embodiment.

p-0184Each of the metering components <b>21</b>-<b>1</b> and <b>23</b>-<b>1</b> of the first and second watt-hour meters <b>21</b> and <b>23</b> measures an amount of electricity at its own installation position (S<b>441</b>).

p-0185Each of the control components <b>23</b>-<b>7</b> of the second watt-hour meters <b>23</b> transmits information on the measured amount of electricity to the first watt-hour meter <b>21</b> through the communication component <b>23</b>-<b>5</b> (S<b>442</b>).

p-0186The control component <b>21</b>-<b>7</b> of the first watt-hour meter <b>21</b> collects the information on the amounts of electricity, respectively received by the second watt-hour meters <b>23</b> through the communication components <b>23</b>-<b>5</b>, and transmits the collected information together with information on the amount of electricity measured by the first watt-hour meter <b>21</b> to the remote server <b>25</b> (S<b>443</b>).

p-0187The control component <b>25</b>-<b>7</b> of the remote meter <b>25</b> receives the information on the amounts of electricity respectively measured by the first and second watt-hour meters <b>21</b> and <b>23</b>, and calculates first and second admittances using the received information on the amounts of electricity (S<b>444</b>).

p-0188The control component <b>25</b>-<b>7</b> of the remote meter <b>25</b> determines the presence of occurrence of electricity theft based on the information on the calculated first and second admittances (S<b>445</b>). In a case where it is determined that the electricity theft has occurred, the remote server <b>25</b> notifies the manager <b>14</b> of the occurrence of the electricity theft through the notification component <b>25</b>-<b>4</b> (S<b>446</b> and S<b>447</b>).

p-0189<figref idrefs="DRAWINGS">FIG. 14</figref> shows an embodiment in which each of the first and second watt-hour meters <b>21</b> and <b>23</b> individually transmits information on impedance to the remote server <b>25</b> in the system of the third embodiment.

p-0190Each of the metering components <b>21</b>-<b>1</b> and <b>23</b>-<b>1</b> of the first and second watt-hour meters <b>21</b> and <b>23</b> measures an amount of electricity at its own installation position (S<b>451</b>).

p-0191The control component <b>21</b>-<b>7</b> of the first watt-hour meter <b>21</b> calculates a first impedance using information on the amount of electricity measured by the metering component <b>21</b>-<b>1</b>, and each of the control components <b>23</b>-<b>7</b> of the second watt-hour meters <b>23</b> calculates a second impedance using information on the amount of electricity measured by the metering component <b>23</b>-<b>1</b> (S<b>452</b>).

p-0192The control component <b>21</b>-<b>7</b> of the first watt-hour meter <b>21</b> transmits information on the calculated first impedance to the remote server <b>25</b> through the communication component <b>21</b>-<b>5</b>, and each of the control components <b>23</b>-<b>7</b> of the second watt-hour meters <b>23</b> transmits information on the calculated second impedance to the remote server <b>25</b> through the communication component <b>23</b>-<b>5</b> (S<b>453</b>).

p-0193The control component <b>25</b>-<b>7</b> of the remote server <b>25</b> receives the information on the first impedance and the information on the second impedances through the communication component <b>25</b>-<b>1</b>, and determines the presence of occurrence of electricity theft based on the received information (S<b>454</b>). In a case where it is determined that electricity theft has occurred, the remote server <b>25</b> notifies the manager <b>14</b> of the occurrence of the electricity theft through the notification component <b>25</b>-<b>4</b> (S<b>455</b> and S<b>456</b>).

p-0194<figref idrefs="DRAWINGS">FIG. 15</figref> shows an embodiment in which the first watt-hour meter <b>21</b> collects information on second impedances respectively calculated by the second watt-hour meters <b>23</b> and transmits the collected information together with information on a first impedance calculated by the first watt-hour meter <b>21</b> to the remote server <b>25</b> in the system of the third embodiment.

p-0195Each of the metering components <b>21</b>-<b>1</b> and <b>23</b>-<b>1</b> of the first and second watt-hour meters <b>21</b> and <b>23</b> measures an amount of electricity at its own installation position (S<b>461</b>).

p-0196The control component <b>21</b>-<b>7</b> of the first watt-hour meter <b>21</b> calculates a first impedance using information on the amount of electricity measured by the metering component <b>21</b>-<b>1</b>, and each of the control components <b>23</b>-<b>7</b> of the second watt-hour meters <b>23</b> calculates a second impedance using information on the amount of electricity measured by the metering component <b>23</b>-<b>1</b> (S<b>462</b>).

p-0197Each of the control components <b>23</b>-<b>7</b> of the second watt-hour meters <b>23</b> transmits information on the calculated second impedance to the first watt-hour meter <b>21</b> through the communication component <b>23</b>-<b>5</b> (S<b>463</b>).

p-0198The control component <b>21</b>-<b>7</b> of the first watt-hour meter <b>21</b> collects the information the second impedances respectively received through the communication components <b>23</b>-<b>5</b> and transmits the collected information together with information on the first impedance calculated by the first watt-hour meter <b>21</b> to the remote server <b>25</b> through the communication component <b>21</b>-<b>5</b> (S<b>464</b>).

p-0199The control component <b>25</b>-<b>7</b> of the remote server <b>25</b> receives the information on the first impedance and the information on the second impedances through the communication component <b>25</b>-<b>1</b>, and determines the presence of occurrence of electricity theft based on the received information (S<b>465</b>). In a case where it is determined that electricity theft has occurred, the remote server <b>25</b> notifies the manager <b>14</b> of the occurrence of the electricity theft through the notification component <b>25</b>-<b>4</b> (S<b>466</b> and S<b>467</b>).

p-0200<figref idrefs="DRAWINGS">FIG. 16</figref> shows an embodiment in which each of the first and second watt-hour meters <b>21</b> and <b>23</b> individually transmits information on an amount of electricity to the remote server <b>25</b> in the system of the fourth embodiment.

p-0201Each of the metering components <b>21</b>-<b>1</b> and <b>23</b>-<b>1</b> of the first and second watt-hour meters <b>21</b> and <b>23</b> measures an amount of electricity at its own installation position (S<b>471</b>).

p-0202The control component <b>21</b>-<b>7</b> of the first watt-hour meter <b>21</b> transmits information on the amount of electricity measured by the metering component <b>21</b>-<b>1</b> to the remote server <b>25</b> through the communication component <b>21</b>-<b>5</b>, and each of the control components <b>23</b>-<b>7</b> of the second watt-hour meters <b>23</b> transmits information on the amount of electricity measured by the metering component <b>23</b>-<b>1</b> to the remote server <b>25</b> through the communication component <b>23</b>-<b>5</b> (S<b>472</b>).

p-0203The control component <b>25</b>-<b>7</b> of the remote server <b>25</b> receives the information on the amounts of electricity respectively measured by the first and second watt-hour meters <b>21</b> and <b>23</b> through the communication component <b>25</b>-<b>1</b>, and calculates first and second impedances using the received information on the amounts of electricity (S<b>473</b>).

p-0204The control component <b>25</b>-<b>7</b> of the remote server <b>25</b> determines the presence of occurrence of electricity theft based on information on the calculated first and second impedances (S<b>474</b>). In a case where it is determined that the electricity theft has occurred, the remote server <b>25</b> notifies the manager <b>14</b> of the occurrence of the electricity theft through the notification component <b>25</b>-<b>4</b> (S<b>475</b> and S<b>476</b>).

p-0205<figref idrefs="DRAWINGS">FIG. 17</figref> shows an embodiment in which the first watt-hour meter <b>21</b> collects information on amounts of electricity respectively measured by the second watt-hour meters <b>23</b> and transmits the collected information together with information on an amount of electricity measured by the first watt-hour meter <b>21</b> to the remote server <b>25</b> in the system of the fourth embodiment.

p-0206Each of the metering components <b>21</b>-<b>1</b> and <b>23</b>-<b>1</b> of the first and second watt-hour meters <b>21</b> and <b>23</b> measures an amount of electricity at its own installation position (S<b>481</b>).

p-0207Each of the control components <b>23</b>-<b>7</b> of the second watt-hour meters <b>23</b> transmits information on the measured amount of electricity to the first watt-hour meter <b>21</b> through the communication component <b>23</b>-<b>5</b> (S<b>482</b>).

p-0208The control component <b>21</b>-<b>7</b> of the first watt-hour meter <b>21</b> collects the information on the amounts of electricity, respectively received by the second watt-hour meters <b>23</b> through the communication components <b>23</b>-<b>5</b>, and transmits the collected information together with information on the amount of electricity measured by the first watt-hour meter <b>21</b> to the remote server <b>25</b> (S<b>483</b>).

p-0209The control component <b>25</b>-<b>7</b> of the remote server <b>25</b> receives the information on the amounts of electricity respectively measured by the first and second watt-hour meters <b>21</b> and <b>23</b>, and calculates first and second impedances using the received information on the amounts of electricity (S<b>484</b>).

p-0210The control component <b>25</b>-<b>7</b> of the remote server <b>25</b> determines the presence of occurrence of electricity theft based on the information on the calculated first and second impedances (S<b>485</b>). In a case where it is determined that the electricity theft has occurred, the remote server <b>25</b> notifies the manager <b>14</b> of the occurrence of the electricity theft through the notification component <b>25</b>-<b>4</b> (S<b>486</b> and S<b>487</b>).

p-0211According to the present invention, it is possible to monitor the presence of electricity theft using admittance or impedance corresponding to each place on an electric power line.

p-0212Particularly, the admittance or impedance is calculated using information on an amount of electricity measured at each place on the same electric power line.

p-0213Since information on amounts of electricity respectively measured at an upper place and several lower places on the same electric power line have a certain correspondence relation, a first admittance (or first impedance) calculated based on the information on the amount of electricity measured at the upper place and second admittances (or second impedances) respectively calculated based on information on the amounts of electricity measured at the lower places also have a certain relation.

p-0214For example, theoretically, the equivalent value of the second admittances (or second impedances) necessarily corresponds to the first admittance (or first impedance).

p-0215Thus, it is possible to precisely determine whether or not electricity theft occurs by monitoring whether or not the equivalent value of the second admittances (or impedances) corresponds to the first admittance (or first impedance) within a certain error range, even though an error of measuring the amount of electricity measured by the watt-hour meter is considered.

p-0216Further, if it is determined that the electricity theft has occurred, the occurrence of the electricity theft is notified to a manager, so that it is possible to allow the manager to take an appropriate countermeasure.

p-0217Although the present invention has been described in connection with the preferred embodiments, the embodiments of the present invention are only for illustrative purposes and should not be construed as limiting the scope of the present invention. It will be understood by those skilled in the art that various changes and modifications can be made thereto within the technical spirit and scope defined by the appended claims.