Air conditioning device and method of room air conditioning

The invention relates to an air conditioning device which regulates the temperature in at least one room by ventilation with heated or cooled air to a predetermined temperature setpoint.

Air-conditioning devices are designed to provide comfortable living conditions in the air-conditioned rooms at any time of the year, by keeping the temperature and humidity of the room air within fixed limits and ensuring adequate ventilation with fresh air.

In winter, the supply air temperature is higher than the room air temperature if the air is to heat the room at the same time, and in summer the supply air is to be blown in at a lower temperature to keep the room at the desired cooled indoor air temperature.

Conventional air conditioning devices roll over a usually too high amount of air whose temperature is adapted to the heating and cooling needs. It is considered disadvantageous that even then a circulation of a large volume of air takes place when the desired target temperature has already been reached. In addition, there is a risk that the supply air blown through the supply air duct in the room and leaves directly to the air-conditioned room again via the exhaust duct. There is a slight mixing of the new supply air with the existing room air.

Furthermore, there is the problem with air conditioning of several rooms, that in the rooms different actual temperatures are present. An adaptation of the temperatures, which takes into account the comfort in each room, is difficult.

The present invention has for its object to provide an air conditioning device that works more economically, ensures comfortable room conditions and optimal mixing of the room air with the supply air to achieve a quick adaptation to the heating, cooling, humidification and dehumidification setpoints.

This object is achieved according to the invention that the air conditioning device, which at least regulates the temperature in at least one room by ventilation with heated or cooled air to a predetermined temperature setpoint, is equipped with a supply air motor, which supplies the supply air via a supply air duct to the room to be conditioned, with a cooling and / or heating device introduced into the supply air duct for cooling or heating the supply air and with an exhaust air motor, which sucks the exhaust air via an exhaust duct from the room to be conditioned, wherein the setpoint for the controller of the exhaust air engine forms a relation to the external pressure set room pressure.

Further advantageous embodiments of the invention form the subject of the dependent claims.

The invention is based on the finding that the greater the overpressure in a room to be air-conditioned, the better the flow through the room with the injected supply air. Thus, the room heats up faster, the efficiency of the system is increased and large temperature fluctuations in the room, for example, very hot at the top and very cool below, but also temperature differences over the length and width of the room can be avoided.

A good flow through the room ensures that a room is heated, cooled, humidified or dehumidified in less time with less air. The lower amount of air blown in is perceived as more pleasant. For faster adaptation of the heating, cooling, humidification and dehumidification set points, the efficiency of the air conditioning device is improved.

In particular, the setpoint value for the controller of the exhaust air motor is determined as a function of the outside temperature and / or the supply air temperature and / or the supply air pressure. This regulation of the exhaust air motor as a function of the outside temperature and / or the supply air temperature and / or the supply air pressure is important for the optimization of the flow. Namely, the higher the supply air temperature or the supply air pressure, the greater the overpressure would have to be for a favorable flow through the room to be conditioned with the supply air. However, the lower the outdoor temperature is, the higher is the supply air temperature in general and thus the higher must be the overpressure in the room to be air conditioned. So it must then be a greater pressure to ensure optimal flow through the room with the injected supply air.

Preferably, on the one hand, the actual value for the controller of the exhaust air motor is formed by the channel differential pressure, which results from the difference between the absolute value of the pressure in the supply air duct and the absolute value of the pressure in the exhaust duct. This ensures that, for example, in air conditioning devices for several rooms disturbances of overpressure by opening windows in individual rooms and thus resulting from the regulation of the exhaust air motor unintentional increase in overpressure in the other rooms due to the pressure loss in the one room is avoided.

On the other hand, the actual value for the controller of the exhaust air motor is preferably formed by the space differential pressure, which results from the difference between the external pressure and the room pressure.

Above all, the room overpressure only changes over a predetermined temperature range of the outside temperature and / or the supply air temperature with a change in the outside temperature or the supply air temperature, wherein at an outside temperature before this temperature range of the room overpressure in each case a certain constant size and at an outside temperature or Supply air temperature after this temperature range of the room over pressure in each case has a further specific constant size. Above all, in the temperature range, the room pressure falls with increasing outside temperature from a maximum overpressure to a minimum overpressure.

Two opposing claims are thereby taken into account. On the one hand, it is necessary for a good flow through the room to be conditioned, that the upper pressure is as large as possible. On the other hand, however, the overpressure must not be too great, because otherwise it is perceived as unpleasant and in the event of excessive overpressure doors open themselves or no longer open or can only be opened or closed with great effort.

In order to ensure a comfortable control and to ensure an overpressure independent of the height or the floor of the room to be air-conditioned, the room differential pressure is measured at a height above 0 (room height). Room height corresponds to the outdoor height in relation to the sea level. According to one embodiment of the invention, the temperature of the supply air and the duct pressure of the supply air are coupled to each other such that both depending on the height of the room temperature to the level of the supply air and in dependence on the height of the room temperature to the height of the setpoint of the room temperature of the channel pressure Supply air into the room, the rooms or room zones is increased or decreased.

The advantages achieved with this are, in particular, that not a large volume of tempered air is circulated unnecessarily, but always only the volume which is required for a maximum rapid adaptation of the actual room values ​​to the predetermined desired values.

In this way not only energy savings are achieved, also it is perceived by the people in the room considerably more pleasant that a stronger air movement takes place only when the temperature of the injected air is far from the actual temperature. In conventional air conditioning devices, however, especially during the morning warm-up even at a room temperature that is well below the set point, only slightly warmed supply air is blown into the rooms with high channel pressure. This was previously considered unpleasant by the individuals concerned, but considered unavoidable.

According to this embodiment of the invention, therefore, heated air is blown into the room with a greater duct pressure only when the temperature of the supply air is well above the predetermined target temperature of the room and thus, in particular in the warm-up phase, far above the actual value of the room. By a ratio control in which the duct pressure of the supply air is set in a fixed ratio to the supply air, a corresponding coupling of the duct pressure of the supply air temperature to the supply air temperature can be realized particularly advantageous according to the invention.

Preferably, the duct pressure of the supply air in the room, the rooms or room zones is set via the line of the supply air motor.

Via a selection device can be selected between two delivery volume behavior.

On the one hand, for the heating case, if the setpoint of the room temperature is lower than the actual value of the room temperature, the duct pressure of the supply air is reduced with increasing room temperature. Accordingly, for the cooling case, if the setpoint of the room temperature is greater than the actual value of the room temperature, the duct pressure of the supply air is reduced with decreasing room temperature. On the other hand, for the heating case, if the setpoint or the actual value of the room temperature is lower than the supply air temperature and the actual value of the room temperature is lower than the setpoint of the room temperature, the duct pressure of the supply air increases with increasing supply air temperature. Accordingly, for the cooling case, if the setpoint or actual value of the room temperature is greater than the supply air temperature and the actual value of the room temperature is greater than the setpoint of the room temperature, the duct pressure increases with decreasing supply air temperature. The increase in the duct pressure of the supply air is perceived as pleasant. In addition, the efficiency of the heating and cooling device is improved, as will be explained below.

According to a further embodiment of the invention, the duct pressure of the supply air changes only over a predetermined temperature range of the supply air temperature. If the supply air temperature has a height before this temperature range, then the duct pressure of the supply air is assigned to a specific constant size. If the supply air temperature has a height according to the temperature range, the duct pressure of the supply air is in each case assigned to a further specific constant variable.

In particular, with a supply air temperature greater than the room temperature over the predetermined temperature range, the duct pressure of the supply air rises from its minimum power to its maximum power with increasing supply air temperature and falls correspondingly with decreasing supply air temperature.

The two regulations of Zuluftkanaldruckverhaltens is on the one hand allows the efficiency of the air conditioning device is improved. With higher duct pressure of the supply air also a faster and better flow through the room and thus a faster heating of the rooms is achieved. On the other hand, but for reasons of comfort too much air flow should be avoided, as this is perceived as unpleasant. These opposite requirements are now optimally done.

The control loop, which regulates the duct pressure of the supply air, is subordinated here to the temperature control circuit, wherein the supply air duct setpoint value can be set in a fixed ratio to the supply air temperature actual value. This avoids excessive overshoot and undershoot during temperature control. The room temperature settles faster to the setpoint temperature.

In the case of air conditioning of several rooms, the heated supply air is made available to all rooms via a common supply air duct. At different target and actual temperatures of all rooms but each room has a different heating needs. To take this circumstance into account, according to a further embodiment of the invention in the case of air-conditioning of simultaneously several rooms or room zones, the individual rooms or Room zones each have their associated supply air and exhaust air line connected to the central Zuluft- and exhaust duct and there are arranged in the individual supply air and / or exhaust ducts throttle, via which the duct pressure of the supply air in the room, the rooms or room zones is set.

This avoids unwanted air movements in rooms whose actual value and setpoint are the same or almost the same. In addition, it is achieved that, for example, not completely fresh air is treated when the fresh air damper is completely open.

The regulation of the throttle valves may additionally be effected in dependence on supply air pressure or the speed of the supply air motor.

In such an independent regulation of supply air temperature and individual room temperature, a situation may arise in which a single room must be heated as quickly as possible, but other rooms, which are already at target temperature, should be heated as little as possible. The individual regulation of these warm rooms will try to close the throttle valves at the increased supply air temperature.

But these rooms and the persons located therein are cut off from the supply of fresh air.

This problem is solved according to a further embodiment advantageous in that even at an inlet air temperature that is above the target temperature, in rooms whose actual temperature corresponds to the target temperature, the required minimum volume of fresh air is blown. In this way it is achieved that these rooms are supplied with sufficient fresh air, yet a possible heating of the rooms due to a supply air temperature that is above the target temperature, as far as possible is avoided. The minimum opening of the butterfly valves required for the given minimum fresh air volume depends on the supply air temperature and the fresh air portion of the supply air, because the fresh air portion of the supply air is, if possible - warming up in the morning - reduced for maximum heating and replaced by circulating air.

According to one embodiment, the exhaust air duct and the supply air duct are connected to one another via a recirculating air duct, at least one exhaust air flap being provided in the exhaust air duct adjoining the exhaust air duct, at least one mixed air damper in the recirculating air duct and at least one fresh air damper in the fresh air duct upstream of the supply air duct.

According to a further embodiment, the minimum cross section of the throttle valves is adjusted in dependence on the opening of the fresh air flap, the exhaust air flap and the mixed air flap, so that in each control situation, the minimum fresh air quantity is ensured.

With regulated duct pressure of the supply air and the exhaust air, the open positions of the mutually associated throttle valves are the same in a room or in a room zone.

Analogous to the heating control can also be a cooling control.

Controllers are used for temperature control. In practice, these controls tend to overshoot and undershoot the controlled variable.

According to a further embodiment of the invention, in each case the manipulated variable of at least one controller, in particular the temperature controller, connected to a downstream switching device, and the switching device selects a predetermined value for the manipulated variable at an overshoot of the controlled variable, which is significantly lower than that of the controller selected value.

Such behavior can be advantageously realized by an additional control device and a minimum selection device. This additional control device delivers a predetermined minimum value for the manipulated variable as a function of the control difference when an overshoot of the controlled variable occurs, and a predetermined maximum value for the manipulated variable when the actual value of the temperature (the controlled variable) is below the desired value. The minimum selector then selects the minimum from the values ​​provided by the controller and the additional controller and passes the selected value as the manipulated variable. In this way, the additional control device always takes control of the manipulated variable, if due to the manipulated variable of the controller overshoot occurs in the controlled variable.

According to a further embodiment of the invention, a fresh air flap in a fresh air duct upstream of the supply air duct, a mixed air flap in a recirculation duct connecting the supply air duct to the exhaust air duct, and an exhaust air flap provided in a subsequent to the exhaust duct exhaust air duct, the positions of the fresh air flap, the exhaust air damper and the mixed air damper are controlled together as a function of the speed of the supply air motor or the duct pressure of the supply air, and wherein up to a certain minimum opening to ensure a fresh air minimum with increasing speed of the supply air motor and / or with increasing duct pressure of the supply air, the opening cross sections of the fresh air damper and the exhaust air damper can be reduced and the opening cross section of the mixing damper can be increased.

The opening position of the fresh air damper and the opening position of the exhaust damper are always the same. The opening position of the mixed air damper is always the difference between the opening position of the fresh air or exhaust air damper to 100%, z. B. If the opening positions of the fresh air flap and exhaust air flap are each 70%, then the opening position of the mixed air flap is 30%. If the mixed air damper has an opening position of 70%, the opening positions of the fresh air and exhaust air damper are each 30%.

In a further preferred embodiment of the invention, more than one room is conditioned by a central facility. Even with different heating requirements of the individual rooms must be made available on the supply air sufficient heating capacity for all rooms. This can include be achieved in that the heating demand is measured at the actual temperature of the coldest room to bring this room in a short time to target temperature can. Therefore, according to an embodiment of the invention in air-conditioning of simultaneously several rooms, the actual temperature of each room is supplied to a central control device, and supplied from these individual actual values ​​to be determined individually temperature value as the actual value for the heating controller.

According to a further embodiment of the invention, a humidifying device is provided, which humidifies the supply air in the supply air duct, wherein the humidifying device is regulated both as a function of the room humidity or the exhaust air humidity and the supply air temperature.

According to a further embodiment of the invention, a first heating device introduced into the supply air duct, a cooling device connected downstream of the first heating device in the supply air duct and a second heating device downstream of the cooling device in the supply air duct are provided for heating, cooling and dehumidifying the supply air, the second heating device being dependent on the Actual humidity is regulated to setpoint humidity.

In particular, with increasing actual humidity, which is already above the setpoint humidity, the heating power of the second heating device increases.

The heating power of the second heating device is controlled either with a controller or increases with increasing actual humidity over a predetermined humidity range of the room humidity at a room humidity before this humidity range, the heating power has a certain constant size and at a room humidity according to the humidity range, the heating power respectively another definite constant size.

This ensures that a dehumidification is effected by increasing the room temperatures, if the actual value of the room temperature remains below the limit from which the cooling process is initiated. It is therefore only then cooled when the actual value of the room temperature is greater than the setpoint of the room temperature plus the temperature difference dependent on the outside temperature. By heating and thus dehumidifying the room via the rising temperature, the room is dehumidified quickly and with a comparatively low expenditure of energy.

The duct pressure of the supply air is not increased during the dehumidification process.

In order to guarantee a minimum amount of fresh air in the room or the rooms, the regulation of the fresh and the exhaust air flap takes place in dependence on the opening position of the mixed air flap.

In the simplest case, a single room is tempered and ventilated with the air conditioning device. The regulation of a multi-room air conditioning is described in detail in the embodiment with reference to the drawing. Show it:<dl id="dl0001"><dt>Fig. 1</dt><dd>a schematic representation of the air circuit of an air conditioning device according to the invention;</dd><dt>Fig. 2</dt><dd>a block diagram with the most important elements of the control and regulating devices of the embodiment;</dd><dt>Fig. 3</dt><dd>a block diagram with important elements of the temperature control circuit of Fig. 2;</dd><dt>Fig. 4</dt><dd>a block diagram of the delivery volume control circuit of the supply air of Fig. 2;</dd><dt>Fig. 5</dt><dd>a block diagram of the individual temperature control circuit for each room of Fig. 2;</dd><dt>Fig. 6a</dt><dd>the relationship between the supply air temperature and the supply air pressure for the embodiment, when the actual room temperature is less than the setpoint room temperature;</dd><dt>Fig. 6b</dt><dd>the relationship between the room temperature and the supply air pressure for the embodiment, when the actual room temperature is greater than or equal to the setpoint room temperature;</dd><dt>Fig. 7</dt><dd>the block diagram of the temperature controller of the embodiment;</dd><dt>Fig. 8a</dt><dd>the block diagram of the controller of the exhaust air engine of the embodiment;</dd><dt>Fig. 8b</dt><dd>the block diagram with the main elements of Fig. 8a;</dd><dt>Fig. 8c</dt><dd>the relationship between the outside temperature and the setpoint of the room differential pressure for the controller of the exhaust air motor;</dd><dt>Fig. 9</dt><dd>the relationship between the room exhaust air humidity and the correcting variable for the reheater; and</dd><dt>Fig. 10</dt><dd>a flowchart with the main involved in the heating process block diagram elements.</dd></dl>

In Fig. 1, the air cycle of a multi-room air conditioning is shown schematically. From the rooms to be air-conditioned 1 lead on one side air supply lines 5 to a supply air duct 10 and on the other side exhaust ducts 6 to an exhaust duct 11th

In the air supply line 5, a throttle valve 60 and in the exhaust duct 6 each have a throttle valve 61 is arranged in each case.

The supply air duct 10 and the exhaust air duct 11 are connected to each other via a recirculating air channel 12.

The supply air duct 10 is preceded by a fresh air duct 20 and the exhaust air duct 11 is followed by a discharge air duct 21.

In the fresh air duct 20, a fresh air flap 70, in the circulating air channel 12, a mixed air flap 72 and in the exhaust air duct 21, an exhaust air flap 71 are provided.

In the supply air duct 10, a first heating device 30, a cooling device 40, a second heating device 33, a supply air motor 15 and a moistening device 50 are arranged one behind the other in the flow direction of the air.

In the supply air duct 10 by the supply air motor 15, an air pressure P_TO generated, which ensures that the supply air is injected with sufficient delivery volume in the rooms to be conditioned 1.

Accordingly, in the exhaust duct 11 through the exhaust air motor 16, a negative pressure P_FROM generated, which sucks the room air.

In the simplest case, the pure aeration case - office operation -, the extracted room air (= the exhaust air) via the exhaust duct 11 and the exhaust duct 21 is discharged to the outside air and the fresh air duct 20, the required supply air is sucked into the supply air duct 10 as fresh air. For this purpose, the fresh air flap 70 and the exhaust air flap 71 are opened and the mixed air flap 72 is closed. The fresh air flap 70 and the exhaust air flap 71 always have the same opening positions.

In order to enable warming of the air-conditioned rooms 1, the fresh air sucked in flows through the first heating device 30 - preheater - via which the intake air to the required supply air temperature T depending on the heating demand_TO is brought. After passing through the non-activated cooling device 40 and the second heating device 33 - reheater - it is the humidifier 50 supplied, which supplies the necessary humidity to the air.

Instead of the first heating device 30, the cooling device 40 is in operation with a required cooling of the spaces to be air-conditioned. If the humidity is too high, instead of the humidifying device 50, the reheater 33 is in operation for dehumidifying. To ensure a more rapid heating, both the first heating device 30 and the second heating device 33 may be in operation. However, this is possible for the heating case, not for the dehumidification case.

The air thus treated is fed via the supply air motor 15, the supply air duct 10 and the supply air ducts 5 with the throttle valves 60 to the individual rooms to be conditioned. The volume of individually injected and extracted in each room air can be individually regulated by the arranged in the air supply lines 5 and in the exhaust ducts 6 throttle 60, 61.

With increased heating demand, for example, in the morning warm-up, it is advantageous to provide the rooms not only with fresh air sucked, but to use a portion of the extracted room air repeatedly, because with the simultaneous warming and ventilation, the required supply air volume is far above the fresh air minimum volume. Therefore, depending on the supply air temperature T_TO via a control device 500 in Fig. 2, a control value y_V calculated and the louvers 550 in Fig. 2 and 70, 71, 72 fed in Fig. 1.

While the fresh air damper 70 and the exhaust air damper 71 receive the same control signal, the mixed air damper 72 in the circulating air duct 12 is supplied with the exactly opposite control signal. The open position of the mixed air flap 72 is always the difference to the open position of the fresh air flap 70 or the exhaust air flap 71 to 100%. For example, the opening position of the fresh air flap 70 and the exhaust air flap 71 are each 70%, the open position of the mixed air flap is 30%. If the mixed air flap has an open position of 70%, then the open position of the fresh air flap 70 and the exhaust air flap 71 are each 30%.

In this way, a certain proportion of the extracted room air via the recirculating air channel 12 can again forward the supply air. At the same time a corresponding proportion of fresh air is supplied via the fresh air duct 20 and the fresh air flap 70 of the supply air. This fresh air content is in the embodiment in the ventilation case - during office hours - up to 100%. During office hours, therefore, the mixed air flap 72 is usually not opened, the fresh air flap 70 and the exhaust air flap 71 are normal to 100% open. With increased heating demand and a maximum supply pressure P_{TO MAX} the fresh air portion drops to about 10% - warming up in the morning -.

In air conditioning, the measured room temperatures T_{ROOM IS 1}, T_{ROOM IS 2} or T_{RAU M IS N} in the minimum selector 400 in Fig. 2, the lowest value T_{SPACE IS MIN} determined and used to calculate the heating demand. For this purpose, the actual temperature T_{SPACE IS MIN} in the block diagram element 100 of the predetermined (maximum) set temperature T_{ROOM SHOULD} (of all rooms) subtracted. Due to the temperature difference T (control difference) thus calculated, the temperature control 130 determines a suitable control value y 'for the heating valve 170 of the heating device 30 in FIG.

The manipulated variable y calculated by the controller 120 in FIG. 3 of the temperature control_R is monitored by the downstream switching device 125 in order to largely prevent overheating of the temperature which is conventional with conventional controllers. Normally, as long as T_{SPACE IS MIN} under T_{ROOM SHOULD} is, the switching device 125 is the manipulated variable y_R unchanged as y 'to the heating valve 170 on. But exceeds T_{SPACE IS MIN} the target temperature T_{ROOM SHOULD}, then instead of y_R a much smaller manipulated variable y 'forwarded to the heating valve 170. The value of the manipulated variable y 'in this case represents the minimum required supply air temperature T_{TO MIN} certainly, which depends on the outside temperature T_A, In this way, in the embodiment, a maximum overshoot is reached by the target temperature of only 0.3 ° C, undershooting takes place as good as not.

The monitoring of the control signal y _R of the controller 120 is realized in the embodiment by a switching device 127 in Fig. 7 and a minimum selector 128. The controller 127 simultaneously generates a control signal y to the controller 120_Swhich assumes a maximum value as long as the target temperature T_{ROOM SHOULD} above the actual temperature T_{SPACE IS MIN} is, up to a very low control value signal y_{S MIN}as soon as the actual temperature exceeds the setpoint.

The manipulated value signal y_{S MIN} the control device 128 is used to cut off the otherwise occurring undershooting of the temperature control as a function of the outside temperature T_Awith which the fresh air is sucked in, set by the calculating means 129.

The minimum selector 128 selects from the two manipulated value signals y available to it_R and y_S each from the smaller and gives this as y 'to the heating valve 170 on. In this way, an overshoot of the temperature to be controlled is suppressed as much as possible.

Depending on the temperature of the supply air, the delivery volume of the supply air motor 15 via the generated supply air pressure P_{TOO IS} set. This is done first in a P_TOOValue calculation means 200 in Fig. 2, a target value P_TOO intended for the supply air pressure.

The relationship between the supply air temperature T_TO and the supply air pressure P_TOO is shown in Fig. 6a, and in the event that the room temperature T_{SPACE IS} less than the setpoint of the room temperature T_{ROOM SHOULD} is.

Only when the supply air temperature is significantly above the setpoint temperature, in the exemplary embodiment by 5 ° C, the target pressure of the supply air is increased. At a supply air temperature below this threshold, only the volume of air necessary for ventilating the rooms is blown into the air-conditioned rooms.

The relationship between the room temperature T_{SPACE IS} and the setpoint of the supply air pressure P_TOO is shown in Fig. 6b in the event that the room temperature T_{SPACE IS} greater than the setpoint of the room temperature T_{ROOM SHOULD} or equal to the setpoint of the room temperature T_{ROOM SHOULD} is.

With rising room temperature T_{SPACE IS}if the room temperature is greater than the setpoint of the room temperature T_{ROOM SHOULD} is, the supply air temperature T decreases_TO and the setpoint of the supply air pressure P_TOO from his maximum pressure P_{TO MAX} to its minimum pressure P_{TO MIN},

The one of the P_TOOValue calculation device 200 in Fig. 2 certain Zuluftsolldruck P_TOO is in the block diagram element 230 with the supply air actual pressure P_{TOO IS} compared. The pressure difference P is the pressure control 250 fed.

The complete pressure control loop is shown in FIG. The control difference P is fed to the controller 240, the manipulated variable y_P established. A limit switch 245 monitors the manipulated variable y_P, so that a predetermined minimum pressure P_{TO MIN}, which does not fall below a predetermined minimum ventilation volume. With the manipulated variable y_P'of the limit switch 245, the fan 285 is controlled in Fig. 4 and 15 in Fig. 1, which generates the pressure of the controlled system 286.

With a corresponding control circuit is a negative pressure P by the exhaust air motor 16 in the exhaust duct 11_FROM generates, which sucks a to maintain a predetermined overpressure in the rooms corresponding air volume again. The regulation of the exhaust air motor 16 will be described below.

The tempered supply air in the supply air duct 10 is on the supply air lines 5 for ventilation and heating of all rooms 1 available. With the help of the throttle valves 60, 61, the volume of individually injected into each room and extracted air is adapted to the actual actual heating demand. In each case, the setpoint temperature, the actual temperature, the supply air temperature and the minimum ventilation volume are used for setting the throttle valves. This control loop, in FIG. 2 shown as a block diagram element 300, in FIG. 5 played.

In the block diagram element 310, the individual target temperature T_{SHOULD N} with the corresponding actual temperature T_{IS N} compared; the determined control difference T_N is supplied to the controller 320. This generates due to the temperature difference T_N, the supply air temperature T_TO and the supply air pressure P_TO an actuating signal y_TN, which may not be less than a minimum value resulting from the current supply pressure P_TO and the minimum pressure P_{TO MIN} results. The actuating signal y_TN is fed to the throttle 330 in Fig. 5 and 60, 61 in Fig. 1. The controlled system of this individual temperature control loop is represented by the block diagram element 340.

The throttle valves 60, 61 are thus dependent on the temperature setpoint T set in each individual room_{ROOM SHOULD}, the actual temperature value T measured in each individual room_{SPACE IS}, the temperature value of the supply air temperature T_TO and as a function of the supply air pressure P_TO and / or the speed of the supply air motor regulated.

As stated above, the control circuit for adjusting the opening cross section of the throttle valves 60, 61 ensures a certain, depending on the Zuluftdrucks resulting Mindestöffnungsguerschnitt which is not exceeded in the setting of the throttle valves 60, 61. This minimum opening cross-section is set so that each room receives a predetermined absolute minimum fresh volume.

The minimum opening area of ​​the throttle valves 60, 61 is also adjusted depending on the opening of the fresh air door 70, the exhaust air door 71 and the mixed air door 72.

In regulated delivery volume of the supply air and the exhaust air, the open positions of the mutually associated throttle valves 60, 61 are the same in a room 1.

In the regulation of the exhaust air motor 785 of Fig. 8b and 16 of FIG. 1, the target value for the exhaust air motor in dependence on the outside temperature in the P_{DIFF SHOULD}Value computing means 710 calculated, this setpoint one with respect to the external pressure P_A depending on the outside temperature set room pressure P_{DIFF SHOULD} forms. The setpoint P_{AB SHOULD} can also be determined depending on the supply air temperature and / or the supply air pressure.

The relationship between the outside temperature T_A and the setpoint for the exhaust air motor / = setpoint for the room overpressure P_{DIFF SHOULD}, which is the difference between the desired value of the exhaust air pressure P_{AB SHOULD} and the external pressure P_A results in is shown in Fig. 8c. When the outside temperature T_A exceeds a certain limit, for example, an outside temperature of - 10 ° C, the setpoint P falls_{DIFF SHOULD} the exhaust air motor with increasing outside temperature of its maximum P_{DIFF SHOULD MAX} to its minimum P_{DIFF SHOULD MIN} at a further limit, for example at an outside temperature of + 15 ° C. At an outside temperature before or after this temperature range determined by the two limit values, the setpoint value of the exhaust air motor P corresponds_{DIFF SHOULD} either the maximum space differential pressure P_{DIFF SHOULD MAX} or the minimum space difference pressure P_{DIFF SHOULD MIN},

The one of the P_{DIFF SHOULD}Value calculation means 710 in Fig. 8a certain setpoint of the exhaust air motor P_{DIFF SHOULD} is in the block diagram element 700 with the difference in room actual pressure P_{DIFF IS} compared with the supply air and exhaust air differential pressure in one room and in several rooms. The pressure difference P is supplied to the pressure control 730.

The complete pressure control loop is shown in Fig. 8b. The control difference Δ P_DIFF is fed to the controller 740, the manipulated variable y_{P DIFF} established. If several windows are open in a large office, the exhaust can be completely switched off - only then a slight overpressure can be maintained -.

With the manipulated variable y_{P DIFF} of the regulator 740, the exhaust air motor 785 in FIG. 8b or 16 in FIG. 1 is controlled, which generates the pressure of the controlled system 786.

The actual value for the controller 740 of the exhaust air motor 16 or 785 is determined by the room differential pressure P_{DIFF IS} formed, which is the difference between the external pressure P_A and the room pressure <maths id="math0001" num=""><math display="inline"><mrow><msub><mrow><mtext>P</mtext></mrow><mrow><mtext>SPACE IS</mtext></mrow></msub><msub><mrow><mtext> = P</mtext></mrow><mrow><mtext>AB IS</mtext></mrow></msub></mrow></math><img file="EP0851179A2_D0001.tif" /></maths> results. The room differential pressure P_{DIFF IS} is measured at a height above 0 (sea level).

The described embodiment can be used analogously to the cooling.

In an additional control loop, the humidity in the air-conditioned rooms is regulated. It is preferably measured and expressed as relative humidity (as a percentage of the vapor pressure at full saturation), hereinafter referred to simply as the symbol F. But it is quite possible, instead of the relative humidity, the absolute humidity (in g of water vapor to a m³ Air), the vapor pressure, the specific humidity (in g H₂O to 1 kg of moist air) or as a mixing ratio (in g H₂O per 1 kg of dry air). When using the relative humidity, the dependence on the saturation limit is advantageously integrated into the value. According to the VDI ventilation rules, the humidity in winter should be 35 to 70% relative humidity at 20 ° C room air temperature, 70% in summer at room temperature 22 ° C, 60% at 25 ° C.

In the block diagram element 600 in FIG. 1, the difference between the setpoint air humidity F_{AB SHOULD} and actual humidity F_{AB IS} determined, wherein representative of the humidity in the individual rooms in the embodiment, the humidity of the exhaust air F_FROM measured and adjusted. The determined humidity difference Δ F_FROM is first supplied to a threshold switching device 610, which due to predetermined minimum and maximum humidity limits F_{FROM MIN} and F_{AB MAX} depending on the supply and exhaust air temperature prevents the saturation limit is exceeded at any point in the air circulation at the humidity control. From this limit switching device 610 is now a corrected control difference Δ F_FROMsupplied to the controller 620, the humidifier 630 via the control signal y_L controls. As a result, the humidity of the supply air F_TO set. The controlled system is represented by the block diagram element 640.

The second heating device 33 may also receive the signal y 'of the first heating device 30 in the case of heating. However, the second heating device 33 serves as a reheater essentially for dehumidifying. This second heating device 33 is dependent on the actual humidity F_IS regulated to setpoint humidity, with increasing actual humidity F_IS above the setpoint humidity F_SHOULD the heating power of the second heating device 33 increases. The increase in the heating power of the second heating device 33 increases over a predetermined humidity range of the room humidity F_IS, This relationship is shown in FIG. With a room humidity F_IS before this humidity range, the second heating device 33 is not in operation.

With a room humidity F_IS After this humidity range, the second heating device 33 - the reheater - with its maximum power in operation.

By a control device not shown here it is ensured that the delivery volume of the supply air is not increased during the dehumidifying process and only a minimum amount of fresh air is blown.

For a better illustration of the control, a warm-up process will be described below by way of example, as it usually takes place in the morning. The block diagram elements involved in the execution of the control are shown in FIG. 10 shown. At the time of switching on the air conditioning device, the actual temperatures of all rooms 1 and the temperature of the intake fresh air should be well below the target temperature for the rooms 1. Since the temperature of the supply air is still very low, no more supply air is blown into the rooms. For this purpose, the supply air motor 15 a minimum fresh air volume corresponding minimum air pressure P_{TO MIN} generated.

When the outside temperature is below 16 ° C, the controller is preset to a value according to the outside temperature at start-up so that the system does not show any frost damage when starting.

Of the actual temperatures of all rooms 1 to be air-conditioned, the minimum selector 400 selects the lowest value and sends it to the block diagram element 100. Here, the control difference .DELTA.T between the setpoint and actual value of the room air temperatures is formed and fed to the controller 120 and the controller 127. The controller 120 determines a control value y due to the control difference .DELTA.T_R, At the same time by the controller 127 is a control value y_S determined, which assumes a maximum value as long as the setpoint temperature is above the actual temperature. Of the two control values ​​y_S and y_R the minimum selector 128 selects the smaller one, at this time the manipulated variable y_R of the regulator 120, and forwards it to the heating device 30. This warms the air flowing through the supply air duct 10 accordingly. This increases the supply air temperature T_TO continuously on. From a predetermined temperature threshold value of the supply air, for example T_TOO + 5 ° C, the supply air pressure is increased as the supply air temperature rises, as the supply air pressure is regulated as a function of the supply air temperature. The delivery volume increases and there is a maximum rapid heating of all rooms.

The increased volume of air is not only fresh air, but a portion of the exhaust air is supplied via the recirculating air duct 12 in Fig. 1 again the supply air. In this way, the rooms 1 are adequately ventilated and at the same time not unnecessarily much fresh air must be heated.

During morning heating, the proportion of fresh air is only - at least - so great that the required overpressure is achieved.

Once the heating process has been completed, commercially available controllers reduce the manipulated variable y_R not sufficiently fast to prevent an increase in the actual temperatures of the rooms 1 above the target temperature. Therefore, the manipulated variable y decreases_S the control device 127 when exceeding the target temperature to a predetermined minimum value y_{S MIN} from. Now, the minimum selector 128 selects the value y_S the controller 127 and passes it as y 'to the heater 30 on. Then the supply air temperature drops again, and after a short time, the rooms are supplied only with the minimum fresh air volume, which is sufficiently tempered to prevent a decrease in the actual temperature of the supply air below the target temperature of the supply air. The controller can thus reduce its output slowly.

It will now also be described the case in which only one room must be heated, while the other rooms have already reached the target temperature. From the minimum selector 400, the lowest actual temperature of the unheated rooms is selected and sent to the block diagram element 100. Due to the control difference, a manipulated variable y 'is now set and the supply air temperature and the supply air pressure increase accordingly. But so that the rooms are not supplied with very warm supply air, which have already reached the target temperature, controls the room temperature individual control 300 via throttle 60, 61 for each room separately the injected air volume. In this way, the throttle valves 60, 61 of the rooms in which the actual temperature has already reached the setpoint temperature, closed to a minimum cross-section, which ensures that the rooms are sufficiently ventilated. At the same time open with increasing T_TO the throttle valves 60, 61 of the space to be heated up to 100% and P_DIFF up to 100% for fast heating. Only when this room has reached its setpoint temperature does the air conditioning control again set the minimum ventilation and setpoint temperature maintenance status.

LIST OF REFERENCE NUMBERS

<dl id="dl0002" compact="compact"><dt>1</dt><dd>to be air conditioned room</dd><dt>5</dt><dd>supply air</dd><dt>6</dt><dd>exhaust pipes</dd><dt>10</dt><dd>supply air duct</dd><dt>11</dt><dd>exhaust duct</dd><dt>12</dt><dd>return air duct</dd><dt>15</dt><dd>supply air</dd><dt>16</dt><dd>exhaust engine</dd><dt>20</dt><dd>Fresh air duct</dd><dt>21</dt><dd>Air duct</dd><dt>30</dt><dd>Heating device (pre-heater)</dd><dt>33</dt><dd>Heating device (reheater)</dd><dt>40</dt><dd>cooler</dd><dt>50</dt><dd>Befeuchtigungseinrichtung</dd><dt>60</dt><dd>throttle</dd><dt>61</dt><dd>throttle</dd><dt>70</dt><dd>Fresh air flap</dd><dt>71</dt><dd>Exhaust air damper</dd><dt>72</dt><dd>Mixed air damper</dd><dt>100</dt><dd>Block diagram element</dd><dt>120</dt><dd>regulator</dd><dt>125</dt><dd>downstream switching device</dd><dt>127</dt><dd>Switching device / control device</dd><dt>128</dt><dd>Minimum selector / control device</dd><dt>129</dt><dd>calculator</dd><dt>130</dt><dd>temperature control</dd><dt>170</dt><dd>Heating valve</dd><dt>200</dt><dd>P_TOOValue calculating means</dd><dt>230</dt><dd>Block diagram element</dd><dt>240</dt><dd>pressure regulator</dd><dt>245</dt><dd>limit switch</dd><dt>250</dt><dd>pressure control</dd><dt>285</dt><dd>supply air</dd><dt>286</dt><dd>controlled system</dd><dt>300</dt><dd>Block diagram element / room temperature individual control</dd><dt>310</dt><dd>Block diagram element</dd><dt>320</dt><dd>regulator</dd><dt>330</dt><dd>throttle</dd><dt>340</dt><dd>Block diagram element</dd><dt>400</dt><dd>Minimum selector</dd><dt>500</dt><dd>control device</dd><dt>550</dt><dd>louver</dd><dt>600</dt><dd>Block diagram element</dd><dt>610</dt><dd>Limit switching device</dd><dt>620</dt><dd>regulator</dd><dt>630</dt><dd>humidifier</dd><dt>640</dt><dd>Block diagram element</dd><dt>700</dt><dd>Block diagram element</dd><dt>710</dt><dd>P_{DIFF SHOULD}Value calculator</dd><dt>730</dt><dd>pressure control</dd><dt>740</dt><dd>regulator</dd><dt>760</dt><dd>controlled system</dd><dt>785</dt><dd>exhaust engine</dd><dt>786</dt><dd>controlled system</dd><dt>P_FROM</dt><dd>exhaust pressure</dd><dt>P_TO</dt><dd>Supply pressure</dd><dt>P_{TOO IS}</dt><dd>Supply air pipe pressure</dd><dt>P_TOO</dt><dd>Supply pressure setpoint</dd><dt>P_{TO MIN}</dt><dd>minimum pressure</dd><dt>T_A</dt><dd>outside temperature</dd><dt>T_{ROOM IS 1}</dt><dd>room temperature</dd><dt>T_{ROOM IS 2}</dt><dd>room temperature</dd><dt>T_{SPACE IS N}</dt><dd>room temperature</dd><dt>T_{SPACE IS MIN}</dt><dd>lowest value</dd><dt>T_{ROOM SHOULD}</dt><dd>(maximum) set temperature</dd><dt>T_{ROOM SHOULD N}</dt><dd>individual target temperature</dd><dt>T_TO</dt><dd>supply air temperature</dd><dt>T_{TO MIN}</dt><dd>minimum permissible supply air temperature</dd><dt>y_V</dt><dd>control value</dd><dt>y '</dt><dd>control value</dd><dt>y_R</dt><dd>control value</dd><dt>y_S</dt><dd>actuating signal</dd><dt>y_{S MIN}</dt><dd>very low control value signal</dd><dt>y_P</dt><dd>manipulated variable</dd><dt>y_{P '}</dt><dd>control value</dd><dt>y_TN</dt><dd>actuating signal</dd><dt>y_L</dt><dd>control signal</dd><dt>F</dt><dd>relative humidity</dd><dt>F_FROM</dt><dd>Moisture of the exhaust air</dd><dt>F_{FROM MIN}</dt><dd>minimum humidity limit</dd><dt>F_{AB MAX}</dt><dd>maximum humidity limit</dd><dt>F_{AB SHOULD}</dt><dd>Target humidity</dd><dt>F_TO</dt><dd>Moisture of the supply air</dd><dt>P_DIFF</dt><dd>Room differential pressure</dd><dt>P_{DIFF IS}</dt><dd>Actual value of the room differential pressure</dd><dt>P_{DIFF SHOULD}</dt><dd>Setpoint of the room differential pressure</dd><dt>ΔP</dt><dd>pressure difference</dd><dt>ΔT</dt><dd>temperature difference</dd><dt>ΔT_N</dt><dd>Control difference</dd><dt>ΔF_FROM</dt><dd>humidity difference</dd><dt>ΔF_FROM'</dt><dd>corrected control difference</dd></dl>