JP2006029693A - Demand control system of multi-air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce peak amount of electric power consumption of the whole building efficiently while ensuring work environment by simple control by operating and controlling air conditioning facility depending on system. <P>SOLUTION: This demand control system of the multi-air conditioner is provided with a prediction computing means 6 for computing prediction amount of electric power used per demand calculation time, an intermittent shutting-off time computing means 8 for determining whether prediction amount of electric power computed by the prediction computing means exceeds a demand value or not and computing intermittent shutting-off time corresponding to exceeding amount of electric power when prediction amount of electric power exceeds the demand value, and an operation control means 9 for performing intermittent/rotation operation switching control in accordance with predetermined order of priority for a plurality of systems dividing the multi-air conditioner into a plurality of groups based on intermittent shutting-off time computed by the intermittent shutting-off time computing means to perform operation switching control of the multi-air conditioner per system so that amount of used electric power within demand calculation time is within a scope of demand value. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a demand control system for a multi-air conditioner that controls power consumption for each demand calculation time of a building by a plurality of systems obtained by dividing the multi-air conditioner into a plurality of groups.

  FIG. 10 is a diagram showing an example of demand electric energy for each year and month in a certain building. Electricity charges consist of basic charges and pay-as-you-go charges. The basic charge is determined by how the power is used, such as the maximum power consumption (demand power consumption). As shown in FIG. 10, the demand power amount varies greatly depending on the season, and in the case of business power, the demand power amount is determined based on a 30-minute track record in which the amount of power consumption is the largest during a period of one year. Therefore, the largest amount of power consumption among 365 days × 24 hours × 2 = 17,520 times determines the basic charge of the annual electricity charge. For this reason, realizing as much leveled power consumption as possible leads to a reduction in power charges.

  In general office buildings, about 40% of the power consumption is consumed by air conditioning equipment. The amount of power consumed by air conditioning equipment varies greatly depending on external weather conditions (external temperature, solar radiation, etc.) and the heat storage status of the building (nighttime, holidays, etc.), especially during peak loads in summer and winter, and during air conditioning operations during open holidays Since the load increases, the power consumption increases accordingly.

In conventional air-conditioning control systems, pre-cooling / preheating control that operates air-conditioning equipment earlier than the normal operating time, as well as cold / hot water circulation during cooling or heating stop, to reduce the demand value at maximum load Circulate to the heat exchanger of the air conditioning pipe and the air conditioner, and the temperature of the chilled water or hot water in the chilled / hot water circulating pipe immediately before the start of cooling or heating and the temperature of the heat exchanger of the air conditioner are cooling water temperature during heating or heating An operation method for maintaining a temperature close to the hot water temperature is considered (for example, see Patent Document 1).
JP 2004-108658 A

  However, the above-mentioned conventional precooling / preheating control focuses on converging the indoor environment to an appropriate value at the start of business hours, and calculates many parameters such as outside air conditions, indoor temperature, air conditioning function, etc. In the method of calculating and circulating cold water or hot water while cooling or heating is stopped, it is installed on the two-way valve installed on the outlet side or inlet side of the heat medium to the air conditioner and the bypass pipe communicating with the two-way valve One or both of the opened / closed valves must be opened while cooling or heating is stopped, and the circulation pump must be operated.

  The present invention solves the above-described problems, and enables the peak power consumption of the entire building to be efficiently reduced while ensuring the work environment through simple control by operating and controlling the air conditioning equipment for each system. It is.

  Therefore, the present invention is a demand control system for a multi-air conditioner that controls the amount of power used for each demand calculation time of a building by a plurality of systems in which the multi-air conditioner is divided into a plurality of groups, and is used for each demand calculation time. A prediction calculation unit that calculates a predicted power amount, and a case where the predicted power amount calculated by the prediction calculation unit exceeds the demand value by determining whether or not the predicted power amount exceeds the demand value Intermittent interruption time calculating means for calculating an intermittent interruption time according to the amount of electric power exceeding, and intermittently according to a predetermined priority order for the plurality of systems based on the intermittent interruption time calculated by the intermittent interruption time calculating means. Operation control means for performing intermittent interruption switching control by rotation operation, and the amount of power used within the demand calculation time is Characterized in that the said to be within the scope of the demand value to perform switching control of the intermittent blocking by multi-air conditioner operation for each line.

  The prediction calculation means calculates the predicted electric energy based on a value obtained by measuring and integrating the electric energy used for an initial fixed time every demand calculation time, or calculates an air conditioning load by measuring information on the air conditioning load. The predicted electric energy is calculated from the air conditioning load, and at least the amount of solar radiation, the outside air temperature, and the room temperature are included as information on the measured air conditioning load.

  The intermittent interruption time calculating means calculates the intermittent interruption time in addition to the minimum intermittent interruption time determined by the characteristics of the air conditioner to a value obtained by multiplying the electric energy in which the predicted electric energy exceeds the demand value by a certain constant. The operation control means sequentially activates the plurality of systems based on the intermittent interruption time when the air conditioning operation is started depending on whether the air conditioning operation is started or during the air conditioning operation. .

  According to the present invention, when the predicted power amount exceeds a preset demand value, the intermittent cutoff time is calculated according to the excess power amount, and intermittent / Since switching control of intermittent interruption by rotation operation is executed, it is possible to achieve both reduction of peak power consumption and securing of work environment (homogenization by system) by a multi-air conditioner.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram for explaining an embodiment of a demand control system for a multi-air conditioner according to the present invention. In the figure, 1 is a heat storage load information sensor, 2 is a sensor information accumulation unit, 3 is a coefficient storage unit, 4 is a holiday information storage unit, 5 is an operation start time deviation calculation unit, 6 is an electric energy prediction calculation unit, and 7 is a setting. An electric energy storage unit, 8 is an intermittent interruption time calculation unit, and 9 is an operation control unit.

  In FIG. 1, a heat storage load information sensor 1 measures information correlated with a heat storage load of a building, and measures, for example, an amount of solar radiation, an outside air temperature, an indoor temperature, and the like. For example, the sensor information accumulating unit 2 can obtain information related to the heat storage load measured by the heat storage load information sensor 1 up to N hours before the registered air-conditioning start time (usually about two hours before). It is cumulative. The coefficient storage unit 3 stores a coefficient for calculating the driving start time deviation based on the value accumulated in the sensor information accumulating unit 2, and the holiday information storage unit 4 opens a holiday (the number of holidays before the driving day). This is to memorize an annual calendar, weekly schedule, etc. The operation start time deviation calculation unit 5 is based on the value accumulated in the sensor information accumulation unit 2, the coefficient stored in the coefficient storage unit 3, the annual calendar or weekly schedule stored in the holiday information storage unit 4, and the like. The deviation is calculated.

  The power amount prediction calculation unit 6 sets the demand calculation time to 30 minutes and performs 30-minute demand prediction. For example, by constantly measuring the power amount pulse of the power receiving wattmeter, the power amount prediction calculation unit 6 measures and integrates the power amount in a predetermined time. The predicted electric energy for 30 minutes is calculated. The set power amount storage unit 7 stores the contract power amount with the power company as a preset demand value (set power amount). The intermittent interruption time calculation unit 8 calculates the intermittent interruption time from the deviation between the predicted electric energy obtained by the electric energy prediction calculation unit 6 and the demand value stored in the set electric energy storage unit 7, or the operation start time The accumulated value, coefficient, calendar and the like of the sensor information are received from the deviation calculation unit 5 and converted into the predicted power amount, and the intermittent interruption time is calculated from the deviation between the predicted power amount and the demand value.

  The operation control unit 9 includes a plurality of systems A, B,... Based on the air conditioning start time deviation calculated and set by the operation start time deviation calculation unit 5 and the intermittent cutoff time calculated and set by the intermittent cutoff time calculation unit 8. For the multi-air conditioner comprising the above, sequential start control at the start of each operation and intermittent cut-off switching control by intermittent / rotation operation are performed.

  As described above, in the present embodiment, the predicted power amount used for each demand calculation time is calculated, it is determined whether the predicted power amount exceeds a preset demand value, and the predicted power amount is the demand value. Is calculated for the plurality of systems A, B, C obtained by dividing the multi air conditioner into a plurality of groups based on the intermittent interruption time. In accordance with the priority order, switching control of intermittent interruption by intermittent / rotation operation is performed, so that the amount of power used within the demand calculation time is within the range of the demand value.

  2 is a diagram for explaining sequential start-up operation for each system of a multi-air conditioner, FIG. 3 is a diagram for explaining 30-minute demand prediction, FIG. 4 is a diagram for explaining intermittent / rotation operation for each system of a multi-air conditioner, and FIG. It is a figure explaining the outline | summary of a prediction calculation process.

When the operation start time deviation calculation unit 5 calculates the air conditioning start time deviation N ′ to be adjusted with respect to N hours before the air conditioning start time (usually about 2 hours before), the operation control unit 9 sequentially selects the multi air conditioners for each system. In the start-up operation, as shown in FIG. 2, the system A is started first before the time determined by the air conditioning start time deviation N ′ from the air conditioning start time, then the system B is delayed by K3 (constant), and the system is further delayed by K3. The start-up operation is sequentially performed with a delay of C and K3. The air conditioning start time deviation N ′ is, for example, when the load conversion coefficient is K1 (constant) and the building heat storage coefficient is K2 (constant), for example, when the outside air temperature is information correlated with the heat storage load of the building,
N ′ = cumulative outside temperature × K1 × K2
Calculated by the following formula:
When the amount of solar radiation is information that correlates with the heat storage load of the building,
N '= cumulative solar radiation x K1 x K2
Calculated by the following formula:
When the outside air temperature and solar radiation amount are correlated with the heat storage load of the building,
N ′ = (cumulative outside air temperature + cumulative solar radiation / α) × K1 × K2
Where α is a constant (solar radiation conversion coefficient)
Calculated by the following formula:
When the room temperature is information correlated with the heat storage load of the building,
N ′ = (deviation between indoor temperature and set temperature during air conditioning) × K1 × K2
Where α is a constant (solar radiation conversion coefficient)
It is calculated | required by the numerical formula of.

  In recent air conditioning equipment systems, many building multi-systems for individual air conditioning are employed, and the system is composed of a plurality of systems. Further, on / off control for each system is possible. For this reason, instead of operating all systems at the same time, measure the information correlating with the heat storage load of the building, and determine the operation start time taking into account whether the day is open (the number of holidays before the operation day) By sequentially starting according to the priority for each system, the peak power consumption at the start of operation of the air conditioner can be dispersed. Note that when the information related to the air conditioning load is measured and accumulated for a few hours to a few dozen hours before the start of operation, an annual calendar, a weekly schedule, or the like is not used regardless of whether the holiday is open or not. Moreover, you may use for the calculation, without accumulating the value which measured the information regarding the air-conditioning load before a driving | operation start.

In the 30-minute demand prediction, as shown in FIG. 3, the demand calculation time is set to 30 minutes, and the amount of power used in the initial fixed time for each demand calculation time is measured and calculated based on the integrated value. When the predicted power amount is obtained, the intermittent cutoff time calculation by the intermittent cutoff time calculation unit 3 determines whether the predicted power amount exceeds the demand value, and the predicted power amount exceeds the demand value. obtains the difference ΔP between the set power amount and the predicted power amount (demand value), based on the amount of power ΔP of the difference, obtaining the intermittent interruption time T _a by the following calculation.

ここで、最小間欠遮断時間Ｔ₀ は、空調機器の特性によって決定される（通常３分程度）。

Here, the minimum intermittent interruption time T ₀ is determined by the characteristics of the air conditioner (usually about 3 minutes).

By this way, the intermittent interruption time T _A obtained, the intermittent-rotation operation, to turn off the system A only intermittent interruption time T _A according to the priority order based on the priority set in advance as shown in FIG. 4, the following Then, the system is switched to the system B and the intermittent cutoff time T _A is switched to the system C, and then the intermittent cutoff time T _A is turned off in order.

  As described above, in the intermittent / rotation operation of the multi air conditioner, N groups are set, and the intermittent interruption operation is performed by sequentially switching from the group having the higher priority among these groups. The priority is changed according to the season by the period setting function, that is, the upper and lower floors depending on the season (cooling mode, heating mode). When the predicted power amount including the load other than the air conditioner is reduced during the intermittent / rotation operation by recalculation, the intermittent / rotation operation is reset.

  For example, as shown in FIG. 5, the power amount prediction calculation process of the power amount prediction calculation unit 1 sets the prediction calculation start time to 0 minutes per hour and 30 minutes, and waits for that time (step S <b> 11). Then, for example, the register that accumulates and holds the electric energy is reset (step S12), and then the electric energy pulse received from the received watt-hour meter is counted in this register to accumulate and hold the electric energy ( Step S13). If N minutes have elapsed (for example, 10 minutes) from the prediction calculation start time (demand start time), and the integration time ends, the integration of the electric energy is continued during that period to determine the end of the integration time (step S14), and the integrated electric energy The predicted power amount after 30 minutes is calculated from the value of (step S15).

  FIG. 6 is a diagram showing another embodiment of the demand control system for a multi-air conditioner according to the present invention, and FIG. 7 is a diagram for explaining the effect of reducing the peak power consumption by the sequential start-up operation for each multi-air conditioner system.

In the demand control system for a multi-air conditioner according to the present invention shown in FIG. 6, the power control device 11 constantly measures the received power amount pulse of the transducer 12, and the sensors 13 and 14 provide information on the air conditioning load such as the solar radiation amount and the outside air temperature. It is configured to acquire the received power amount, information on the air conditioning load, and system operation control information from the external communication unit through the Internet and communicate with the host computer 15. Then, similarly to the system of the previous embodiment, the power control device 11 performs switching control of sequential start-up operation by system and intermittent interruption by intermittent / rotation operation, and the host computer 15 acquires the actual solar radiation amount and the actual outside air temperature. In addition, the heat load is calculated from the building specifications of the building to predict the air conditioning load. For example, the operation start time deviation N ′ is calculated by N ′ = air conditioning start time air conditioning load / air conditioner rated capacity and Send driving instructions. As a result, the power control apparatus 11 performs operation control based on the operation instruction from the host computer 15. By realizing these controls, the peak power consumption that appears particularly at startup can be reduced as shown in FIGS. 7A to 7B.

  FIG. 8 is a diagram showing an example of a change in COP (coefficient of performance) when an on / off control and inverter-controlled air conditioner are operated in combination, and FIG. 9 explains a tendency of average COP (coefficient of performance) corresponding to the number of times of off. FIG.

  In the inverter controlled (b) air conditioner, as shown in FIG. 8, the on / off control (b) air conditioner is in the region (L) where the on / off control (b) air conditioner is combined to achieve light load operation. The COP (coefficient of performance) is worse than that in the region (R) where the process is stopped. Further, in an air conditioner with on / off control (b), the COP (coefficient of performance) becomes worse as the number of times of off per unit time increases as shown in FIG. As is clear from these facts, the COP (coefficient of performance) can be improved as a whole by reducing the number of times the air conditioner is turned off. Therefore, the COP (coefficient of performance) of the air conditioner can be improved by increasing the off time. Can be better.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation is possible. For example, what kind of group each multi-air conditioner system can be set can be set according to the importance (room environment), power consumption, and target contract power consumption of each group (multiple systems) of the building. It goes without saying that it is done. In addition, intermittent / rotation operation of air conditioning equipment can achieve energy savings with little impact on the indoor environment. Therefore, intermittent / rotation operation may be performed regardless of the predicted power consumption. As control, a reference value may be provided and desired operation control may be performed on condition that the reference value is exceeded.

  Some recent air conditioners have a function of performing inverter control at light loads, but intermittent operation that does not consider the control function of the air conditioner may deteriorate the indoor environment. A control adaptation period may be provided to perform intermittent / rotation operation with the period as a constant energy saving operation mode, and the energy saving operation mode may not be used in the middle of spring or autumn.

It is a figure explaining embodiment of the demand control system of the multi air-conditioner which concerns on this invention. It is a figure explaining the starting operation according to the system | strain of a multi air conditioner. It is a figure explaining 30 minute demand prediction. It is a figure explaining the intermittent and rotation operation according to system of a multi air conditioner. It is a figure explaining the outline | summary of an electric energy prediction calculation process. It is a figure which shows other embodiment of the demand control system of the multi air-conditioner which concerns on this invention. It is a figure explaining the reduction effect of the peak power consumption by the sequential starting operation according to the system of a multi air conditioner. It is a figure which shows the example of a change of COP (coefficient of performance) when carrying out the combination driving | operation of the air conditioner of on / off control and inverter control. It is a figure explaining the tendency of the average COP (performance coefficient) corresponding to the frequency | count of OFF. It is a figure which shows the example of the demand electric energy according to each year and month in a certain building.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Thermal storage load information sensor, 2 ... Sensor information accumulation part, 3 ... Coefficient memory | storage part, 4 ... Holiday information storage part, 5 ... Operation start time deviation calculating part, 6 ... Electric power amount prediction calculating part, 7 ... Setting electric energy storage Part, 8 ... intermittent interruption time calculation part, 9 ... operation control part

Claims (6)

A multi-air conditioner demand control system that controls the amount of power used for each demand calculation time of a building by a plurality of systems in which the multi-conditioner is divided into a plurality of groups.
Prediction calculation means for calculating a predicted power amount used for each demand calculation time;
It is determined whether or not the predicted power amount calculated by the prediction calculation means exceeds a preset demand value, and when the predicted power amount exceeds the demand value, an intermittent interruption time corresponding to the excess power amount is determined. Intermittent interruption time calculating means for calculating,
An operation control means for controlling switching of intermittent interruption by intermittent / rotation operation according to a predetermined priority order for the plurality of systems based on the intermittent interruption time calculated by the intermittent interruption time calculating means, and the demand calculation time A demand control system for a multi air conditioner, wherein switching control of intermittent interruption by operation of the multi air conditioner is performed for each of the systems so that the amount of electric power used in the system falls within the range of the demand value. 2. The multi-air conditioner according to claim 1, wherein the prediction calculation unit calculates the prediction power amount based on a value obtained by measuring and integrating the power amount used in an initial fixed time for each demand calculation time. Demand control system. The demand control system for a multi-air conditioner according to claim 1, wherein the prediction calculation means calculates an air conditioning load by measuring information on the air conditioning load and calculates the predicted electric energy from the air conditioning load. 4. The demand control system for a multi-air conditioner according to claim 3, wherein the information on the measured air conditioning load includes at least an amount of solar radiation, an outside air temperature, and an indoor temperature. The intermittent interruption time calculating means calculates the intermittent interruption time in addition to the minimum intermittent interruption time determined by the characteristics of the air conditioner to a value obtained by multiplying the electric energy in which the predicted electric energy exceeds the demand value by a certain constant. The demand control system for a multi-air conditioner according to claim 1. The operation control means sequentially activates the plurality of systems based on the intermittent cutoff time when the air conditioning operation is started, depending on whether the air conditioning operation is started or during the air conditioning operation. The demand control system for a multi-air conditioner according to 1.

Images