Method and apparatus for measuring the consumption of an element of an electrical network

The present invention relates to a measuring method of the power consumption of electrical appliances connected to an electricity distribution network.

The control of energy consumption, including of the electric energy consumption is a problem to which the consumer is increasingly sensitive. he thus exists at present a need clearly formulated by the electricity suppliers to submit to their subscribers, whether they are individuals or businesses, a detailed statement of consumption electrical electrical appliances they use. A Such a survey would indicate the cost of consumption electrical and time of use of each appliance on the invoiced period. Various statistics as the hourly cost of using a device, the Average daily life of the device, total cost of the electricity consumption of the appliance Since its commissioning, etc. could also be presented to subscribers.

At present, the known method the less costly to implement to achieve this goal is based on a continuous measurement of the instantaneous power overall consumed in the network, and on detection of energized and off of each device by observation of changes in power consumption. A Once powered on and off each detected device, it is easy to deduce the power consumption of each device, which is equal the product of the power consumed and the time operation of the apparatus (electric power).

Figure 1 illustrates the implementation of this method classic and schematically shows a network 1. The electricity distribution network 1, type single phase, comprises an electric counter CPT1, a line phase P1 and a line of neutral N1 and divides here six sections T1 to T6 via a Box fuses FB1 including fuses F1 to F6. of the E1 to E3 electrical appliances are connected to the section T1, apparatus E4 and E5 are connected to the section T2, and E6 devices, E7, E8, E9 are connected sections respectively T3, T4, T5, T6. a power meter 2 connected to a digital calculating means 3 as a microcomputer, is arranged between the counter CPT1 and point network division. The meter delivers 2 way recurrent, for example every tenth of a second, instantaneous power consumed, which comprises active power Pa (UIcosφ) and reactive power (UIsinφ), U is the amplitude of the alternating voltage on the network, the amplitude I of the current, and the φ current / voltage phase shift.

Each unit has a power consumption determined, measured during a learning phase, changes in active and reactive powers Pa Pb consumed allows the microcomputer 3 to identify devices turned on or off. So, Following the example illustrated in Figure 2, a variation dP1 positive, at a time t1, the active power Pa consumed helps to know that the E2 device, eg a vacuum cleaner, whose consumption is equal to the dP1 variation, has been turned on. Has instants t2 and t3, positive changes and dP2 of dP3 power consumption allow to know that E4 and E6 devices, for example a lamp and an oven, have also energized. At a time t4, a dP4 negative change equal to dP1 allows that E4 device has been turned off, and negative variations DP5 and DP6 to t5 and t6, respectively equal to dP1 dP3 and allow to know the E2 and E6 devices have been turned off, etc ..

Examples of methods for identifying electrical devices based on a measure of power consumption are described in US Patents 5 483 153, US 4,858,141, and FR 2 680 875. In particular, US Patent 5,483,153 describes in connection with its Figures 2 to 6 different "signatures" of consumption electrical, or variations in the power curve, expressed in watts and whose determination requires precise and complex measuring a consumption Instant, or dissipated energy.

Although satisfactory in theory, processes Identification devices by measuring power prove difficult to implement and offer high percentage of misidentification devices when they have substantially the same consumption or even the consumption profile start-up. It was believed to correct this problem by observing changes in the reactive power (two devices with the same active power consumption do not necessarily have the same consumption reactive power) but the improvement seen is partial. Thus, two appliances complex, for example a washing machine and a washing machine dishes, each comprising various electrical components such as resistors, a motor, electronic circuits, may comprise two similar electric elements and be confused.

The present invention aims to overcome this disadvantage.

More particularly, an object of the present invention is to provide a method which is more reliable that the method described above with respect to identifying devices turned on or off voltage.

More particularly, the present invention is a means of further analysis, other than the variation the power consumption, enabling the identification devices turned on or off.

This object is achieved by a method for measuring of the electrical consumption of at least one element electrically connected to a distribution network electricity, comprising a recurrent step for measuring the overall instantaneous power consumed on the network and at least a step of detecting a power is or off of the electric element, in wherein tensioning the detecting step or off of the electrical element comprises a step for detecting at least one high electrical signal Representative frequency of the electric element and Independent power consumption, generated on the network when power or disposal voltage of the electrical element.

According to one embodiment, the electrical signal is naturally generated by the electric element, and is a parasitic electrical pulse.

According to one embodiment, the electrical signal is produced by a generator circuit of high signal frequency associated with the electric element, when the power voltage and / or power-off the item electric.

According to one embodiment, the detecting step the high frequency signal comprises a step recording high frequency signal in a form digital and a step of identifying the high signal frequency.

According to one embodiment, the detecting step turning on or off of the element Electric further comprises a verification step of comparing the variation of the power Instant consumed on the network when the power or off of the electric element with a predetermined value of power consumed by the element electric.

According to one embodiment, the step of verification comprises a comparison step of Active power variation consumed in the network with a predetermined amount of active power consumed by the electric element, and a step of comparing the variation in reactive power consumed in the network with a predetermined value reactive power consumed by the electric element.

According to one embodiment, the electrical element is an element of an electrical appliance comprising a plurality of electrical elements may be turned on or off independently of each other.

The present invention also relates to a device for measuring the electrical consumption of at least one electrical element connected to a network electricity, comprising means for measure of overall instantaneous power consumed the network and means for detecting a power is or off of the electric element, in wherein the detection means comprise means for detecting a high frequency electrical signal Representative of the electric element and independent its electrical consumption, generated in the network to time of switching on or off the electric element.

According to one embodiment, the device includes means for recording in digital form high frequency signals appearing in the network, assigning each high frequency signal stored the date and time of its detection.

According to one embodiment, the means for register are arranged to also record overall instantaneous power values ​​consumed on the network measured by the measuring means, by attributing to each value stored the date and time of measurement. According to one embodiment, the means for recording are arranged to record continuously in a buffer the voltage or current profile in the network after high-pass filtering, according to a window determined temporal width of observation, and save the contents of the buffer in a mass storage when a high frequency signal appears in the observation window.

According to one embodiment, the means for Register the form of a device arranged autonomous recording to deliver a output the contents of the mass memory and erase then the contents of the mass memory, the means for measurement being integrated in the recording device autonomous or connected to the latter by a channel data transmission.

According to one embodiment, the device comprises calculating means connected to the means for register arranged to identify high signals Registered frequency and calculate consumption the electric element from the dates of implementation under voltage and / or power-off the item electrical and changes in power consumption.

According to one embodiment, the means of detecting power and decommissioning voltage of the electrical element comprises a circuit high frequency signal transmission associated with the element electrical, arranged to generate a high frequency signal on the network to power and / or decommissioning voltage of the electrical element.

According to one embodiment, the device comprises at least one repeater device connected in a determined point in the network, arranged to amplify a high frequency signal emitted by an electrical device distance detection means of high signal frequency.

Of course, the expression "powered" refers in the present application in that the element or considered the device is activated (starting, lighting, lighting ...) and not only the fact that taking electric element is connected to the network.

These objects, features and advantages others of the present invention will clearly detail in the following description of the method of the invention and an exemplary embodiment of a consumption detecting device implementing this process in connection with the accompanying wherein:<ul><li>Figure 1 described above represents a network electricity distribution,</li><li>Figure 2 is a diagram of consumption active power consumed in the network of Figure 1 and illustrates a conventional method of measuring the power consumption of connected electrical elements to the network,</li><li>3 shows a high electrical signal frequency emitted by an electric element to being placed under voltage or power is turned off,</li><li>4 shows a distribution network electricity comprising a measuring device consumption according to the invention,</li><li>5 is an electrical diagram of a device detection and storage of high-frequency signals shown diagrammatically in FIG 4, and</li><li>6 shows the structure of a memory buffer represented in block form in Figure 5.</li></ul>

Description of the invention

It is known that any electrical element, including resistance, motor, pump, transformer, bulb electrical, electrical or electronic circuit ... has seen its power supply input a complex impedance and generates at its power and is turned off, a high parasitic electrical signal frequency of very short duration, having an origin electromagnetic. Such a signal, which is independent of the power consumption of the electric element, takes the form of an alternating pulse of a frequency the order of 20 MHz and with a duration of the order of 250 nanoseconds, whose amplitude can range from ten millivolts to a few volts (a voltage of 220 Volt) as the reactive component (self or capacity) of the element and the power it absorbs. To fix ideas is shown in Figure 3 the waveform electric parasite transmitted by a iron at its power, detected by means of an oscilloscope.

Such an electrical pulse forms a kind of "Signature" of the element, representative of the power is voltage or power is turned off. In practice two items of the same kind and similar power does never have the same signature, since it depends various factors like the length of the connecting cables elements to the grid, the type of switch ensuring power, the length of the network section to which they are connected, etc ..

The present invention provides leverage the existence of such a high frequency signal to detect powerups or off devices or electrical components of these devices. In a way Generally, the detection of the impulse signing emitted by a device or apparatus part is a safer and more effective identification criterion a simple analysis of the power consumed.

However, preferably, the detecting step and recognition of each pulse transmitted on the network has been completed, as a verification by a step vector comparison of the variation of the power Instant consumed with the rated power the identified device, preferably measured in power Pa active and reactive power Pr. This step Further, in constituting the prior method the only means of recognition of a device, allows up, if applicable, uncertainty about the signature. As discussed below, this step allows especially not to store in memory glitches cyclically issued by some devices do not corresponding to put on or off voltage.

The detection and identification of a high signal frequency transmitted on the network and forming a signature So impulse is an essential step distinguishes the process of the invention of the prior art. Such detection includes a detection step itself of the pulse and a step Identification of the pulse compared with an pulse pattern prerecorded during a phase learning.

Initially, the Applicant has carried out various preliminary tests to verify the appropriateness and feasibility of the process. The tests were ducts by means of a digital oscilloscope connected to an electrical network via a transformer insulator high pass. A network were connected devices about thirty, including lamps and various household appliances. The signal delivered by digital oscilloscope was analyzed by a microcomputer. Meanwhile, a digital power meter delivered to the computer the instant power overall consumed in the network with a frequency of measurement of the order of one second. During a phase learning and storing profiles pulse, it appeared that electrical appliances complex as a washing machine can generate ten different signatures according to the cycle current washing (pre-washing, heating, washing, emptying, rinsing ...) due to various electrical components present in such an apparatus (resistors, motor, pump, valve, timer ...). other by devices emit against a single signature. A Once the various signatures stored in the microcomputer, together forming a database recognition of pulses, the evaluation phase process has been performed and the detected pulses on the network were compared by the microcomputer the pre-recorded pulse by means of an algorithm signal correlation in itself conventional. The obtained success rate, that is to say the percentage non marred error identifications, was about 90%, or an excellent result for experimental system using a database reduced size for recognizing pulses.

The essential features of the process of the invention being described, an object of the invention is now to provide a system for carrying out this method in the subscriber without necessary to use a laboratory apparatus as a oscilloscope.

Implementation of the method of the invention

4 shows a distribution network power 10 according to that of Figure 1. The network 10, here single phase, includes an electric meter CPT1, a line phase P1 and a line of neutral N1, and is divided into six sections T1 to T6 through a fuse box in FB1. E1 electrical appliances to E9 are connected to sections T1 to T6, as described in preamble.

The method of the invention is implemented using a measuring device comprising a wattmeter digital 11, a device 12 for detecting and storage of pulses, and a microcomputer 13 which may be the microcomputer of the subscriber (e.g. family PC for an individual or any computer company). The power meter 11 is connected between the counter CPT1 and point division of the network. The device 12 is connected here, as the meter, between the counter CPT1 and point division of the network, but can also be connected anywhere on the network because the high frequency pulses issued by units spread in all network sections.

The device 12 stores in a mass memory 12-1 the high frequency pulses appearing on the network, generated by the power-ups and put off E1 to E9 and devices various components. Each pulse is stored digital format with allocation of a date. A date includes the year, month, day, and time at which the pulse has been detected and stored, preferably with accurate to one hundredth of a second. according to a optional but advantageous aspect of the invention, the device 12 also stores in the mass memory 12-1 of the power values ​​consumed and Pa reactive power consumption delivered by the Pr power meter 11. Here, Pa values ​​are available Pr PREG register in a power meter 11 and is read by the device 12 by means of a parallel link 14. Pa values, Pr are read into the register PREG regular intervals, for example every second, and are stored in the mass memory 12-1 with allocation of storage date. The contents of the 12-1 memory is transferred by the device 12 to the microcomputer 13, upon request of the latter, by via a serial link 15 of wire type or radio. After the data transfer, the device 12 erases the contents of the memory 12-1. Of Preferably, the memory storage capacity of 12-1 mass is enough to record pulse detected and the power values ​​Pa, Pr on period of weeks when stopping the microcomputer 13, for example when the subscriber is absent.

An embodiment of the device 12 is illustrated in Figure 5. The device 12 receives the sector voltage U that is applied to a divider bridge voltage comprising three resistors 20, 21, 22, and that a power supply circuit 23 outputting the voltage DC power supply Vcc of the device 12. The voltage attenuated at the terminals of the resistor 21 is applied to the primary of a transformer insulator high-pass 24 having an order of the cutoff frequency 150 KHz. The secondary of the transformer is 24 applied to the input of a follower amplifier 25 whose output is applied to an analog-digital converter 26. The output of the converter 26, here on 8 bits, outputs a sampled signal Us sent to a storage circuit 27.

The storage circuit 27 is a circuit logic with a fast clock frequency, directed by example in the form of a monolithic integrated circuit FPGA. The storage circuit 27 includes a Circuit sequencer SEQ provided with a quartz oscillator oscillating at a frequency of about 100 MHz, a MEM1 memory buffer, here 256 bytes, a memory auxiliary buffer MEM2 256 bytes and also a logic comparator COMP. The memories MEM1 and MEM2 are of shift memories respectively driven by LOAD1 load signals, and signal LOAD2 SHIFT1 shift, SHIFT2 issued by the circuit SEQ. The sequencer SEQ applied to the converter 26 a signal SMPL sampling of 100 MHz and the signal sampled Us is applied to the IN1 input of the MEM1 memory. OUT1 of the memory MEM1 is connected to the IN2 input of the memory MEM2. The comparator COMP receives on a first input a word THR bit forming a detection threshold and a second input a binary word taken from the MBYT Memory MEM1 shift, preferably a word lying the middle of the memory, for example the rank of word 128. Figure 6 represents exemplary a fashion achieving the memories MEM1, MEM2, by juxtaposition eight parallel shift register SREG1 to SREG8 of 256 bits each, eight cells in parallel of each registers forming a memory line.

The device 12 also comprises a MC microcontroller and a memory constituting the MEM3 mass memory 12-1, for example, a FLASH memory, OID of which address entry is controlled by the microcontroller MC. The microcontroller MC has its own clock generator circuit and operates at a frequency lower than the acquisition circuit 27, for example 20 MHz. DBUS data to the bus Microcontroller MC is connected to the input data DTIN of MEM3 and out of memory MEM2 auxiliary circuit 27. The data bus DBUS is also connected to an asynchronous serial port type UART (Universal Asynchronous Receiver Transmitter) connected output to the microcomputer 13, and the register PREG the power meter 11, through the connection 14. The parallel link 14 here comprises of 8 son 1 data and wireless control by which the microcontroller READP sends a signal reading of the PREG register.

The device 12 operates as follows. The signal They sampled delivered by the converter 26 is recorded verbatim (word 1 = 1 sample) in the MEM1 memory. This is done under the control SEQ circuit which applies to the memory MEM 1, after sending each sampling pulse SMPL, a LOAD1 load signal and an offset signal SHIFT1. The memory MEM 1 is thus a memory rotating FIFO ( "first in first out") in wherein the sampled signal Us circulates permanently. The memory MEM 1 defines a window observation whose width is equal to the product of the sampling period by the number of samples it contains, either by a command window of 2.56 microseconds, wide enough to capture pulses of a duration less than one microsecond. In the absence of high frequency pulse, the signal Us is close to zero because of the assured high-pass filter by the transformer 24, and the word taken from MBYT middle of the time window is less than the threshold THR. When a pulse is transmitted over the network by a electrical apparatus, the feedback signal Us profile the pulse and the word MBYT becomes greater than the threshold THR. The logic comparator COMP then delivers a signal DETECT the circuit SEQ and it unloads the contents the memory MEM1 MEM2 in the auxiliary memory, then sends to the microcontroller MC a signal indicative PLSDET a pulse was transferred to the memory MEM2. The microcontroller MC then transfers the contents of the MEM2 memory in the mass memory MEM 3, using the SHIFT2 signal, assigning the recorded date signal it is registered as has already been indicated above. Alongside these recording operations pulse, random, the microcontroller MC reads every second the meter and PREG register records the instantaneous power values ​​Pa, Pr in MEM3. Advantageously, the microcontroller checks, after each record of a pulse, that The power Pa, Pr consumed on the network before and after the pulse has a variation. If the microcontroller finds no change power, it erases the memory MEM3 pulse recorded. Thus, the pulses do not correspond to power-ups of or off of devices are not registered and do not unnecessarily encumber MEM3. As indicated above, the content the MEM3 is transferred at regular intervals the microcomputer 13 and is then MEM3 deleted.

In practice, the operation by the microcomputer data (detected pulses and power consumed) stored by the circuit 12 requires the development an indexed database comprising, for each apparatus E1 to E9, the description of the appliance, or more representative of the signatures put under or off of the device, one or more power values ​​Pa active and reactive power Pr consumed each power value being consumed associated with a signature. The development of such a database data during a learning phase is itself comparable to the prior art method, although the signatures of devices are taken here into account.

A first embodiment of phase Learning is to provide the microcomputer list of connected devices and their rated power theoretical. The microcomputer stores in a first time couples signing / power consumption Pa, Pr without knowing what devices they are, and associates then each device a couple signing / power consumed by bringing the power consumption observed and theoretical nominal power. The power consumption value measured by the power meter 11 replaces the theoretical nominal power value initially provided. In some cases, the microcomputer may ask the user to perform power-ups and off, to raise uncertainties.

Another way of learning more conventional simply to provide the microcomputer list of connected devices. Microcomputer then asks the user to turn on and off one or more times each device, for recording of the emitted signature and power consumed by each device.

It will be clear to the skilled person that the This invention is capable of various variants and embodiment. In particular, the device 12 may be equipped with an analog pulse detector arranged the output of the amplifier 1, replacing comparator COMP. The meter 11 can be integrated into the device 12 in the form of an electronic card printed circuit board, the assembly requires only one network connection. The device 12 can be equipped a modem and transmit directly to a server, via The Internet, the data recorded in the MEM3. Such a server is able to have a large database developed from the information from many devices Similar installed at other subscribers and may ensure the rapid identification of various devices from the sensed signatures and the calculation of the Detailed consumption. Alternatively, the data are transferred to the server by the microcomputer 13.

Furthermore, the method according to the invention is applicable to phase networks in providing a pulse detection and power measurement each network phase.

Finally, according to yet another embodiment of the present invention, the high-frequency signals forming a signature for identifying the switching on or off of an apparatus electric are artificially generated by means of a pulse generating circuit associated with the apparatus electric. This embodiment may be considered when an electric device, for example a lamp low power, produces only a weak pulse amplitude. The pulse generator device may be a simple RC circuit or LC incorporated into an outlet electrical interlayer arranged between the plug of the unit and a wall AC outlet, or system contactless induction arranged on the cord of the machine's power. The device emits a special impetus when the current appears or disappears into the outlet or power cord.

On the other hand, the pulse amplifiers repeater type can be installed in sections network of great length in which the pulses are attenuated before reaching the device 12, by example of network sections distributing current in a house with several floors with a counter Single in the basement.

In a more elaborate variant, the device pulse generator emits high-frequency signals encoded, for example a pulse sequence comprising a determined number of pulses forming a signature unique. Such a circuit coded pulse generator the human scope of art and can be achieved by example by means of an oscillator, a logic circuit and a small transformer. In addition, such a circuit coded pulse generator can be integrated into all kinds of household appliances by manufacturers themselves, for a reduced cost, using the transformer of the power supply circuit devices to send the coded signal on the network. Supposing that the use of such circuits pulse generators is generalized, the method according to the invention may, in term, be implemented entirely digitally and only be based on a coded pulse detection artificially issued. It is also possible to combine a detection signal transmitted parasites naturally by certain devices with detection coded signals from other devices with a pulse generator circuit.