Power saving system, power saving device, control method and program for air conditioner

Abstract

This power saving system (1) comprises an air conditioner (2), and a control device which manages power saving by causing the air conditioner (2) to perform a power saving operation. The control device comprises: a normal charge calculation unit (14) which predicts power consumption from operation state information acquired by an operation state information acquisition unit (13) and calculates a normal charge on the basis of the predicted power consumption and a trend of unit electricity charge predicted by an electricity charge prediction unit (12); a power saving charge calculation unit (15) which predicts saved power in a power saving state from the acquired operation state information, and calculates a power saving charge on the basis of the predicted saved power and the trend of unit electricity charge predicted by the electricity charge prediction unit (12); a determination unit (16) which obtains an amount of money reduced by power saving from the normal charge and the power saving charge, and determines whether the power saving operation should be performed when the obtained amount of money is greater than a set amount of money; and an air-conditioning control unit which operates each component of the air conditioner (2) in the power saving state.

Description

[Technical Field]

[0001] This disclosure relates to an energy-saving system, an energy-saving device, a control method for an air conditioner, and a program. [Background technology]

[0002] Energy-saving systems are systems that manage the power consumption of electrical equipment and appliances in homes, businesses, etc. Some of these systems save energy by managing the operation of air conditioners, as air conditioners account for a large portion of the total power consumption in homes and businesses.

[0003] For example, Patent Document 1 discloses an energy-saving device that calculates the electricity cost of an air conditioner consumed over a predetermined period based on information on the unit price of electricity. This energy-saving device evaluates the operation of the air conditioner based on the calculated electricity cost and the comfort level over a predetermined period based on the operating state of the air conditioner, and determines the operating state in which the evaluation is optimal. As a result, this energy-saving device achieves energy saving while maintaining the comfort level of the air conditioner. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2018-40510 [Overview of the project] [Problems that the invention aims to solve]

[0005] In the retail electricity business, the unit price of electricity may fluctuate depending on the demand for electricity. When electricity is supplied from such a retail electricity business, the power saving device described in Patent Document 1 cannot adequately respond to fluctuations in the unit price of electricity because the unit price information for electricity is a predetermined unit price.

[0006] This disclosure is made to solve the above-mentioned problems and aims to provide an energy-saving system, energy-saving device, control method and program for an air conditioner that can adequately manage energy conservation even when the unit price of electricity fluctuates according to the demand for electricity. [Means for solving the problem]

[0007] To achieve the above objectives, power saving related to this disclosure Device teeth , sky The air conditioner is set to operate in energy-saving mode. The system Your device dea ru. Energy saving The device includes an electricity rate information acquisition unit, an electricity rate prediction unit, an operating status information acquisition unit, and a normal rate calculation unit. Energy saving fee calculation section The system includes the following: The electricity rate information acquisition unit acquires electricity rate unit price information for a certain period including the present. The electricity rate forecasting unit predicts the trend of electricity rate unit prices from the present until the forecast period has elapsed, based on the electricity rate information acquisition unit for a certain period acquired by the electricity rate information acquisition unit. The operating status information acquisition unit acquires information on the operating status of each component of the air conditioner from the control unit of the air conditioner. The normal rate calculation unit is , electric The electricity rate forecasting unit calculates the normal electricity rate when the air conditioner is operated in the normal operating state during the forecast period, based on the predicted trend in electricity rates. The energy saving rate calculation unit predicts the amount of energy saved when the air conditioner is operated in the energy saving state from the operating state information acquired by the operating state information acquisition unit, and calculates the energy saving rate when the air conditioner is operated in the energy saving state during the forecast period, based on the predicted energy saving and the predicted trend in electricity rates. 。 [Effects of the Invention]

[0008] According to the configuration of the present disclosure, the electricity price prediction unit predicts the transition of the unit price of the electricity price from the present until the prediction period elapses, and based on the predicted transition of the unit price of the electricity price, the normal price calculation unit and the power saving price calculation unit calculate the normal price and the power saving price. Then, the determination unit obtains the amount reduced by power saving from the calculated normal price and power saving price, and determines that power saving operation should be performed when the obtained amount exceeds the set amount. For this reason, even when the unit price of the electricity price fluctuates according to the demand for electricity, the power saving system can effectively save power by determining whether the amount reduced by power saving exceeds the set amount. As a result, the power saving system can perform sufficient power saving management.

Brief Description of Drawings

[0009] [Figure 1] Refrigerant circuit diagram of an air conditioner included in a power saving system according to an embodiment of the present disclosure [Figure 2] ph diagram showing the refrigerant state of an air conditioner included in a power saving system according to an embodiment of the present disclosure [Figure 3] Hardware configuration diagram of a power saving system according to an embodiment of the present disclosure [Figure 4] Block diagram of a power saving system according to an embodiment of the present disclosure [Figure 5] Diagram showing an example of electricity price unit price information used in a power saving system according to an embodiment of the present disclosure [Figure 6] Diagram showing an example of power consumption information used in a power saving system according to an embodiment of the present disclosure [Figure 7] Diagram showing an example of power saving information used in a power saving system according to an embodiment of the present disclosure [Figure 8] Flowchart of power saving processing performed by a power saving device included in a power saving system according to an embodiment of the present disclosure [Figure 9] Flowchart of super heat control processing performed by a control unit of an air conditioner included in a power saving system according to an embodiment of the present disclosure

Embodiments for Carrying Out the Invention

[0010] Hereinafter, a power-saving system, a power-saving device, a control method for an air conditioner, and a program according to embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or equivalent parts are denoted by the same reference numerals.

[0011] The power-saving system according to the embodiment is a system that saves power by operating an air conditioner using superheat control to set the superheat to 0°C. First, referring to FIGS. 1 and 2, the configuration of the air conditioner and superheat control will be described. Hereinafter, superheat control will be referred to as SH control.

[0012] FIG. 1 is a refrigerant circuit diagram of an air conditioner 2 included in the power-saving system according to the embodiment. In FIG. 1, the four-way valve is omitted for easy understanding. The flow of the refrigerant during heating operation is indicated by arrow A.

[0013] As shown in FIG. 1, the air conditioner 2 includes a compressor 10 that compresses the refrigerant, an indoor heat exchanger 20 that exchanges heat between the refrigerant and indoor air, an expansion valve 30 that expands the refrigerant, and an outdoor heat exchanger 40 that exchanges heat between the refrigerant and outside air. The compressor 10, the indoor heat exchanger 20, the expansion valve 30, and the outdoor heat exchanger 40 are connected in this order to form a refrigerant circuit 3.

[0014] The compressor 10 is a device that converts a low-pressure refrigerant into a high-pressure refrigerant by compressing it. The compressor 10 has a suction port and a discharge port (not shown), and sucks a low-pressure refrigerant from the suction port. Then, the refrigerant is compressed to a high pressure. The magnitude of the pressure of the refrigerant is determined by a command from the control unit 50 to the compressor 10 where the compressor 10 is electrically connected to the control unit 50. Then, the compressor 10 discharges the high-pressure refrigerant from the discharge port.

[0015] The intake and discharge ports (not shown) of the compressor 10 are connected to a four-way valve (not shown). The indoor heat exchanger 20 and the outdoor heat exchanger 40 are connected to this four-way valve by refrigerant pipes. The control unit 50 shown in Figure 1 is electrically connected to the four-way valve. As a result, under the control of the control unit 50, the four-way valve directs the refrigerant from either the indoor heat exchanger 20 or the outdoor heat exchanger 40 to the intake port of the compressor 10. The four-way valve also directs the high-pressure refrigerant discharged from the compressor 10 to the other of the indoor heat exchanger 20 or the outdoor heat exchanger 40. In this way, the four-way valve switches the direction of refrigerant flow in the refrigerant circuit 3. As a result, the four-way valve switches the operating state of the air conditioner 2 to either cooling or heating operation.

[0016] The compressor 10 supplies refrigerant to the indoor heat exchanger 20 by switching a four-way valve, as indicated by arrow A in Figure 1. The air conditioner 2 performs both cooling and heating operations, and the direction indicated by arrow A shows the direction in which the refrigerant flows when the air conditioner 2 is in heating operation. To facilitate understanding, the following explanation of each component will assume that the air conditioner 2 is in this heating operation state.

[0017] The indoor heat exchanger 20 is, for example, a fin-and-tube type heat exchanger. The indoor heat exchanger 20 exchanges heat between indoor air and a refrigerant flowing through the tubes. Specifically, the indoor heat exchanger 20 has tubes (not shown) through which high-pressure refrigerant compressed by the compressor 10 is supplied. On the other hand, the indoor heat exchanger 20 has fins (not shown) through which indoor air is blown from a fan 21 whose rotational speed is controlled by the control unit 50. The indoor heat exchanger 20 exchanges heat between the refrigerant flowing through the tubes and the indoor air blown through the fins. As a result, the indoor heat exchanger 20 releases heat into the indoor air and condenses the refrigerant. Consequently, the indoor heat exchanger 20 functions as a condenser. As a result, the indoor heat exchanger 20 warms the indoor air. Consequently, the indoor heat exchanger 20 heats the room. The indoor heat exchanger 20 discharges the condensed refrigerant to the expansion valve 30.

[0018] The expansion valve 30 is, for example, a solenoid valve or an electric valve and comprises a valve body. The expansion valve 30 opens and closes the flow path of the refrigerant using its valve body. A control unit 50 is electrically connected to the expansion valve 30, and the output of the control unit 50 controls the degree to which the flow path is opened by the valve body. The refrigerant is then depressurized according to the degree to which the flow path is opened. As a result, the expansion valve 30 depressurizes the refrigerant to a pressure corresponding to the output of the control unit 50 and expands it. The expansion valve 30 then flows the expanded refrigerant to the outdoor heat exchanger 40.

[0019] The outdoor heat exchanger 40, like the indoor heat exchanger 20, is, for example, a fin-and-tube type heat exchanger. The outdoor heat exchanger 40 exchanges heat between outside air taken in from outside and refrigerant flowing through tubes. In detail, the outdoor heat exchanger 40 has tubes (not shown) through which refrigerant expanded by the expansion valve 30 flows. On the other hand, the outdoor heat exchanger 40 has fins (not shown) through which outside air is blown from a fan 41 whose rotation speed is controlled by the control unit 50. As a result, the indoor heat exchanger 20 exchanges heat between the refrigerant flowing through tubes and the outside air blown onto the fins, causing the refrigerant to evaporate. The outdoor heat exchanger 40 functions as an evaporator. The outdoor heat exchanger 40 returns the evaporated refrigerant to the compressor 10.

[0020] In this way, the air conditioner 2 performs heating operation to warm the indoor air by switching the four-way valve. The state of the refrigerant at this time is shown in Figure 2.

[0021] Figure 2 is a pH diagram showing the refrigerant state of air conditioner 2. In Figure 2, the horizontal axis represents the enthalpy of the refrigerant, and the vertical axis represents the refrigerant pressure. Also, for ease of understanding, Figure 2 shows saturated liquid line 61 and saturated vapor line 62.

[0022] First, the refrigerant is compressed by the compressor 10, becoming a high-pressure, high-temperature gas as shown in the path from point A to point B in Figure 2, and flows into the indoor heat exchanger 20. The refrigerant that flows into the indoor heat exchanger 20 is then condensed, changing from a gaseous state to a single-phase liquid state as shown in the path from point B to point C in Figure 2. Subsequently, the single-phase liquid refrigerant flows into the expansion valve 30, where it changes from a single-phase liquid state to a low-pressure gas-liquid two-phase state as shown in the path from point C to point D in Figure 2. As a result, the low-pressure refrigerant is supplied to the outdoor heat exchanger 40. In the outdoor heat exchanger 40, the refrigerant exchanges heat with the outside air and is depressurized, changing from a gas-liquid two-phase state to a gaseous refrigerant as shown in the path from point D to point A in Figure 2, and flows into the compressor 10.

[0023] In such a change in the state of the refrigerant, if the temperature of the refrigerant at point A in Figure 2, i.e., the temperature TS of the refrigerant at the inlet of the compressor 10, is too high compared to the saturation temperature of the refrigerant, the compressor 10 will overheat. In other words, if the degree of superheat SH is too high, the compressor 10 will overheat. As a result, the power consumption of the air conditioner 2 will increase.

[0024] Here, the degree of superheat SH refers to the temperature rise from the saturation temperature of the refrigerant. Generally, the refrigerant becomes superheated vapor at the outlet of the evaporator. In such cases, the degree of superheat SH is the temperature of the refrigerant at the inlet of the compressor 10, T S The temperature of the refrigerant flowing through the tubes of the outdoor heat exchanger 40, that is, the temperature of the refrigerant in the evaporator, is T E In this case, the temperature T defined by Equation 1 SH This matches. In the superheat control process described later, it is assumed that the refrigerant becomes superheated vapor at the outlet of the evaporator, so the degree of superheating SH is the temperature obtained from Equation 1.

[0025]

number

[0026] Thus, a high superheating degree SH results in high power consumption for the air conditioner 2. As can be understood from this, reducing the superheating degree SH reduces the power consumption of the air conditioner 2. The energy-saving system 1 utilizes this phenomenon to save energy. Specifically, the energy-saving system 1 reduces the power consumption of the air conditioner 2 by using SH control to set the superheating degree SH to 0°C.

[0027] Next, the configuration of the power saving system 1 will be explained with reference to Figure 1, as well as Figures 3-7.

[0028] Figure 3 is a hardware configuration diagram of the power saving system 1 according to an embodiment. Figure 4 is a block diagram of the power saving system 1. Figure 5 is a diagram showing an example of electricity rate unit price information 110 used in the power saving system 1. Figure 6 is a diagram showing an example of power consumption information 111 used in the power saving system 1. Figure 7 is a diagram showing an example of power saving information 112 used in the power saving system 1. In addition, in Figures 3 and 4, the server 5 of the electric utility company connected via the network 100 is also shown for ease of understanding.

[0029] As shown in Figure 3, the power saving system 1 comprises an air conditioner 2 and a power saving device 4 that causes the air conditioner 2 to perform power saving operation.

[0030] The air conditioner 2 includes a control unit 50 to control the operation of the four-way valve, compressor 10, fan 21 of the indoor heat exchanger 20, expansion valve 30, and fan 41 of the outdoor heat exchanger 40. The control unit 50 has a microprocessor 51, memory 52, and network interface 53. These microprocessor 51, memory 52, and network interface 53 are connected by a bus 54.

[0031] The memory 52 includes the operation data storage unit 55 shown in Figure 4. It also stores various programs for controlling each part of the air conditioner 2, such as an operation program and a superheat control program.

[0032] The network interface 53 connects the microprocessor 51 to the various sensors shown in Figure 4. Specifically, the network interface 53 connects the microprocessor 51 to the compressor inlet temperature sensor 56 located at the refrigerant inlet of the compressor 10 shown in Figure 1, the compressor outlet temperature sensor 57 located at the refrigerant outlet of the compressor 10, the indoor heat exchanger temperature sensor 58 located on the tube of the indoor heat exchanger 20, and the outdoor heat exchanger temperature sensor 59 located on the tube of the outdoor heat exchanger 40. As a result, the microprocessor 51 obtains data on the refrigerant temperature detected by the compressor inlet temperature sensor 56, the compressor outlet temperature sensor 57, the indoor heat exchanger temperature sensor 58, and the outdoor heat exchanger temperature sensor 59.

[0033] Returning to Figure 3, the microprocessor 51 performs operation processing that controls the operation of the four-way valve, compressor 10, indoor heat exchanger 20 fan 21, expansion valve 30, and outdoor heat exchanger 40 fan 41 by executing the operation program described above. For example, the microprocessor 51 uses the refrigerant temperature data obtained from the various sensors described above to control the four-way valve, compressor 10, indoor heat exchanger 20 fan 21, expansion valve 30, and outdoor heat exchanger 40 fan 41. As a result, the microprocessor 51 performs a series of processes that perform SH control to set the superheat level SH to 0°C, hereinafter referred to as the superheat control process.

[0034] The microprocessor 51 and memory 52 are connected to the power saving device 4 via the network 100, for example via the internet, through the network interface 53, in order to receive a command on whether or not to perform this superheat control processing. As a result, the microprocessor 51 and memory 52 can communicate with the power saving device 4.

[0035] The power saving device 4 comprises a processor 45, memory 46, and network interface 47. The processor 45, memory 46, and network interface 47 are connected by a bus 48, similar to the case of the control unit 50.

[0036] The network interface 47 connects the processor 45 and memory 46 to external devices, such as the control unit 50 of the air conditioner 2 and the electric utility's server 5, via the network 100. This enables the network interface 47 to communicate with the control unit 50 of the air conditioner 2 or the server 5.

[0037] On the other hand, the processor 45 and memory 46 constitute a computer. The memory 46 includes various storage units used for power saving processing. Specifically, the memory 46 includes a charge prediction data storage unit 25, a power consumption data storage unit 26, a power saving data storage unit 27, and a parameter storage unit 28, as shown in Figure 4. Here, power saving processing refers to the process of determining whether power saving is effective or not, and issuing a command for superheat control processing if it is determined that power saving is effective. Furthermore, the memory 46 stores a power saving program for performing this power saving processing.

[0038] The power saving device 4 performs the power saving process described above by having the processor 45 read and execute a power saving program stored in the memory 46. To perform this power saving process, the power saving device 4 includes a functional block configured as software as shown in Figure 4. In detail, the power saving device 4 includes an electricity rate information acquisition unit 11, an electricity rate forecasting unit 12, an operating status information acquisition unit 13, a normal rate calculation unit 14, a power saving rate calculation unit 15, a determination unit 16, and a command unit 17.

[0039] In the electricity business, Demand Response (DR) is implemented to change electricity demand patterns by raising or lowering electricity rates. Server 5, on the other hand, is a terminal device operated by the electricity company, and it transmits information on fluctuations in electricity rates due to DR to trading partners such as consumers and renewable energy companies. For example, Server 5 transmits electricity rate unit price information 110, which associates the time of electricity demand and the electricity rate per kilowatt-hour as shown in Figure 5, to trading partners. The electricity rate information acquisition unit 11, shown in Figure 4, acquires the electricity rate unit price information 110 by receiving it via the network 100. Then, the electricity rate information acquisition unit 11 transmits the acquired electricity rate unit price information 110 to the electricity rate forecasting unit 12.

[0040] The electricity rate forecasting unit 12 is provided to forecast electricity rates for a further future and longer period than the future electricity rates included in the electricity rate unit price information 110. When the electricity rate forecasting unit 12 receives the electricity rate unit price information 110, it uses an electricity rate forecasting model to forecast the trend of electricity rates from the present until the forecast period has elapsed.

[0041] In detail, the price prediction data storage unit 25 shown in Figure 4 stores data of a trained prediction model generated by training a neural network with a large amount of electricity price information 110 obtained in the past. That is, the price prediction data storage unit 25 stores data of a trained prediction model obtained by training a neural network using the relationship between the trend of electricity price units over a certain period before a certain time and the trend of electricity price units over a period corresponding to the above-mentioned prediction period after a certain time as training data. For example, the price prediction data storage unit 25 stores weight data of the connections between nodes of the neural network and node data of the neural network. The electricity price prediction unit 12 reads the trained prediction model data from the price prediction data storage unit 25 and constructs a trained prediction model from that data. The electricity price prediction unit 12 applies the electricity price information 110 obtained from the electricity price information acquisition unit 11 to the constructed trained prediction model and predicts the trend of electricity price units from the present until the prediction period has elapsed. The electricity rate forecasting unit 12 transmits the predicted electricity rate trend data to the normal rate calculation unit 14 and the energy saving rate calculation unit 15.

[0042] On the other hand, the operating status information acquisition unit 13 is provided to obtain data for predicting the power consumption of the air conditioner 2. The operating status information acquisition unit 13 acquires operating status data of each component of the air conditioner 2 from the control unit 50 of the air conditioner 2 via the network 100.

[0043] In detail, in the air conditioner 2, information indicating the operating status of each component, such as the switching direction of the four-way valve, the frequency of the compressor 10, the rotational speed of the fan 21 of the indoor heat exchanger 20, the opening degree of the expansion valve 30, and the rotational speed of the fan 41 of the outdoor heat exchanger 40, i.e., operating status data, is stored in the operating data storage unit 55 for each control operation by the control unit 50. The operating status information acquisition unit 13 causes the control unit 50 to read the operating status data for each of the above components from the operating data storage unit 55 and transmit the read operating status data. In this way, the operating status information acquisition unit 13 acquires the operating status data of the air conditioner 2. The operating status information acquisition unit 13 transmits the acquired operating status data to the normal charge calculation unit 14 and the energy saving charge calculation unit 15.

[0044] The standard rate calculation unit 14 is provided to calculate the electricity bill when no energy saving measures are taken. The power consumption data storage unit 26 stores the power consumption information 111 shown in Figure 6, which was obtained through experiments. In this power consumption information 111, the power consumption is associated with the operating status data of each component, such as the switching direction of the four-way valve, the frequency of the compressor 10, the rotation speed of the fan 21 of the indoor heat exchanger 20, the opening degree of the expansion valve 30, and the rotation speed of the fan 41 of the outdoor heat exchanger 40, which are acquired by the operating status information acquisition unit 13. When the standard rate calculation unit 14 shown in Figure 4 receives operating status data from the operating status information acquisition unit 13, it reads the power consumption information 111 from the power consumption data storage unit 26.

[0045] The normal charge calculation unit 14 determines which of the operating state data included in the read power consumption information 111 matches or approximates the received operating state data. Then, the normal charge calculation unit 14 calculates the power consumption of the air conditioner 2 when it is operating in the state indicated by the received operating state data, based on the power consumption data associated with the operating state data that it has determined to match or approximate. In other words, it predicts the power consumption.

[0046] Furthermore, the normal charge calculation unit 14 receives electricity rate trend data from the electricity rate forecasting unit 12, and calculates the charge for operating the air conditioner 2 under the conditions indicated by the above operating status data from the present until the forecast period has elapsed, based on the received electricity rate trend data and the predicted power consumption. This charge will be hereinafter referred to as the normal charge. The normal charge calculation unit 14 then transmits the calculated normal charge data to the determination unit 16.

[0047] In contrast, the power saving charge calculation unit 15 is provided to calculate the electricity charge when power saving is performed. The power saving data storage unit 27 stores the power saving information 112 shown in Figure 7, which was obtained through experiments. In this power saving information 112, the operating state data of each component, which is identified by the switching direction of the four-way valve, the frequency of the compressor 10, the rotational speed of the fan 21 of the indoor heat exchanger 20, the opening degree of the expansion valve 30, and the rotational speed of the fan 41 of the outdoor heat exchanger 40, is associated with the power consumption when switching to SH control from the operating state of each component, i.e., the power consumption during power saving. The power saving charge calculation unit 15 shown in Figure 4 receives operating state data from the operating state information acquisition unit 13, reads the power saving information 112 from the power saving data storage unit 27, and determines which of the operating state data included in the read power saving information 112 matches or approximates the received operating state data. The energy saving charge calculation unit 15 then predicts the power consumption of the air conditioner 2 when it switches from the operating state indicated by the received operating state data to the energy saving state, based on the power consumption during energy saving associated with the operating state data that it has determined to match or approximate.

[0048] The energy saving charge calculation unit 15, similar to the normal charge calculation unit 14, receives data on the trend of electricity rates from the electricity rate forecasting unit 12, and calculates the energy saving charge if the air conditioner 2 is operated in an energy-saving state from the present until the forecast period has elapsed, based on the received data on the trend of electricity rates and the predicted power consumption during energy saving. The energy saving charge calculation unit 15 then transmits the calculated energy saving charge data to the determination unit 16.

[0049] The determination unit 16 receives data on the normal charge from the normal charge calculation unit 14 and data on the energy saving charge from the energy saving charge calculation unit 15. It then subtracts the energy saving charge from the normal charge to determine the amount that will be reduced due to energy saving. Meanwhile, the parameter storage unit 28 stores data on a set amount, which is the threshold for determining whether or not to perform SH control, or in other words, energy-saving operation. The determination unit 16 reads the set amount data from the parameter storage unit 28 and determines whether or not the amount that will be reduced due to energy saving exceeds the set amount. Based on this, the determination unit 16 determines whether or not to perform energy-saving operation.

[0050] If the determination unit 16 determines that the amount saved by saving electricity exceeds a set amount, and therefore electricity-saving operation should be performed, the command unit 17 sends an electricity-saving command signal to the control unit 50 of the air conditioner 2. This causes the control unit 17 to instruct the control unit 50 of the air conditioner 2 to perform electricity-saving operation, i.e., SH control. As a result, the air conditioner 2 operates in an electricity-saving state, and its power consumption decreases. This reduces electricity costs.

[0051] Next, with reference to Figures 8 and 9, the operation of the power saving system 1, the power saving device 4, and the control unit 50 of the air conditioner 2 will be described. In the following description, it will be assumed that the power saving device 4 is activated when a start switch (not shown) of the power saving device 4 is pressed. Also, it will be assumed that the air conditioner 2 is activated when a power button (not shown) of the air conditioner 2 is pressed. Furthermore, it will be assumed that after the air conditioner 2 is activated, either cooling operation or heating operation is automatically selected, and as a result, the air conditioner 2 performs heating operation.

[0052] Figure 8 is a flowchart of the power saving process performed by the power saving device 4. Figure 9 is a flowchart of the superheat control process performed by the control unit 50 of the air conditioner 2.

[0053] When the power saving device 4 and the air conditioner 2 are activated by a start switch and power button (not shown), the power saving program is executed by the processor 45 of the power saving device 4, and the power saving process flow shown in Figure 8 begins.

[0054] First, as shown in Figure 8, the power saving device 4 obtains electricity rate information 110 from the server 5 (step S1). For example, the power saving device 4 obtains electricity rate information 110 that includes the trend of electricity rates from the present to one hour later.

[0055] Next, the power saving device 4 predicts the future trend of electricity rates from the electricity rate unit price information 110 (step S2). As described above, the power saving device 4 reads the data of the trained prediction model from the rate prediction data storage unit 25 shown in Figure 4 and constructs a trained prediction model from that data. Then, the power saving device 4 applies the electricity rate unit price information 110 obtained in step S1 to the constructed trained prediction model to predict the trend of electricity rates from the present until a prediction period, for example, 24 hours or 48 hours have passed.

[0056] Next, the power saving device 4 acquires operating status data from the air conditioner 2 (step S3). The power saving device 4 acquires operating status data for each component, such as the switching direction of the four-way valve, the frequency of the compressor 10, the rotational speed of the fan 21 of the indoor heat exchanger 20, the opening degree of the expansion valve 30, and the rotational speed of the fan 41 of the outdoor heat exchanger 40, from the control unit 50 of the air conditioner 2.

[0057] Furthermore, the power saving device 4 may, via the control unit 50, acquire data on the refrigerant temperature detected by the compressor inlet temperature sensor 56, the compressor outlet temperature sensor 57, the indoor heat exchanger temperature sensor 58, and the outdoor heat exchanger temperature sensor 59 as described in Figure 4, and treat this refrigerant temperature data as part of the operating status data. This is because adding such data to the operating status data allows for a more accurate determination of the state of the air conditioner 2.

[0058] When the power saving device 4 acquires operating status data, it calculates the normal electricity charge if the air conditioner 2 is operated in the state indicated by the operating status data (step S4). As described above, first, the power saving device 4 reads power consumption information 111 from the power consumption data storage unit 26 and uses the read power consumption information 111 to predict the power consumption of the air conditioner 2 when it is operated in the state indicated by the operating status data acquired in step S3. Next, the power saving device 4 calculates the electricity charge, i.e., the normal charge, assuming that the unit price of electricity charges changes as predicted in step S2, when the air conditioner 2 operates at the predicted power consumption from the present until the predicted period has elapsed.

[0059] Next, the power saving device 4 calculates the electricity cost when the air conditioner 2 is operated in a power saving state (step S5). As described above, the power saving device 4 reads the power saving information 112 from the power saving data storage unit 27 and uses the read power saving information 112 to predict the power consumption when switching from the state indicated by the operating state data acquired in step S3 to SH control. Then, as in step S4, the power saving device 4 calculates the electricity cost assuming that the unit price of electricity changes as predicted in step S2, when the air conditioner 2 operates at the predicted power consumption from the present until the predicted period has elapsed. The power consumption at this time is the cost when operating in SH control, that is, in a power saving state. Therefore, the calculated electricity cost is the electricity cost when operating in a power saving state.

[0060] Furthermore, when calculating the electricity saving charge, it is sufficient to calculate the charge assuming that the air conditioner 2 operates at the predicted power consumption for the entire period from the present until the end of the predicted period. However, it is also acceptable to calculate the charge assuming that the air conditioner 2 operates at the predicted power consumption for only a portion of the entire period from the present until the end of the predicted period, for example, for a short period such as 10 minutes, 30 minutes, or 1 hour. Additionally, although it complicates the calculation of the electricity saving charge, it is also acceptable to calculate the charge assuming that the air conditioner 2 operates at the predicted power consumption only during specific time periods, for example, only at night or only in the morning. This is because operating the air conditioner 2 at the predicted power consumption only during such periods, i.e., operating in an energy-saving state, makes it less likely that the comfort of the air conditioning will be compromised. Moreover, energy saving is possible even with such operation.

[0061] The power saving device 4 calculates the amount that will be reduced by saving electricity by calculating the normal charge and the energy saving charge (step S6). In detail, the power saving device 4 calculates the amount that will be reduced by saving electricity by subtracting the energy saving charge from the normal charge.

[0062] Next, the power saving device 4 determines whether the amount of money saved by power saving exceeds a set amount (step S7). Specifically, the power saving device 4 reads the data of the set amount, which is the threshold, from the parameter storage unit 28 and determines whether the amount of money saved by power saving, as determined in step S6, exceeds the read set amount.

[0063] If the power saving device 4 determines that the amount of money saved by saving electricity does not exceed the set amount (No in step S7), it determines that sufficient cost reduction cannot be achieved even if electricity is saved, and instructs the control unit 50 of the air conditioner 2 to continue operating in its current state. In other words, the control unit 50 does not perform the superheat control processing described later.

[0064] The power saving device 4 returns to step S1 after a certain amount of time has elapsed since it determined that the amount saved by saving electricity does not exceed a set amount. For example, if the electricity rate unit price information 110 obtained in step S1 only includes the change in electricity rates from the present to one hour later, the power saving device 4 returns to step S1 after only one hour has elapsed since the determination. Alternatively, if the electricity rate unit price information 110 includes electricity rates every 10 minutes, the power saving device 4 returns to step S1 after only 10 minutes have elapsed since the determination. As a result, the power saving device 4 obtains the latest electricity rate unit price information 110 in step S1 again and executes steps S2-S7 with this latest electricity rate unit price information 110. As a result, the power saving device 4 uses the latest electricity rate unit price information 110 to confirm whether sufficient cost reduction can be achieved through saving electricity.

[0065] On the other hand, if the power saving device 4 determines that the amount of money saved by saving electricity exceeds a set amount (Yes in step S7), it determines that sufficient cost reduction can be achieved by saving electricity and sends a power saving command signal to the control unit 50 of the air conditioner 2 (step S8).

[0066] When the power saving device 4 transmits a power saving command signal to the control unit 50 of the air conditioner 2, the control unit 50 executes a superheat control program using the microprocessor 51, and as a result, superheat control processing is performed (step S9).

[0067] In the superheat control process, first, the control unit 50 determines whether the superheating degree SH shown in Figure 9 is above a certain value (step S91). Specifically, the control unit 50 first acquires temperature data measured from the compressor inlet temperature sensor 56 and the outdoor heat exchanger temperature sensor 59. From this, the control unit 50 obtains the refrigerant temperature TS at the inlet of the compressor 10 and the temperature of the refrigerant flowing through the tubes of the outdoor heat exchanger 40, i.e., the refrigerant temperature TE of the evaporator. Then, it calculates the superheating degree SH from the difference between temperature TE and temperature TS. Once the superheating degree SH is calculated, the control unit 50 determines whether the superheating degree SH is above a certain value, for example, whether the superheating degree SH is 1°C or higher. From this, the control unit 50 determines whether the superheating degree SH is too close to 0°C and therefore SH control is not possible.

[0068] If the control unit 50 determines that the superheating degree SH is above a certain value (Yes in step S91), it treats the superheating degree SH as being sufficiently greater than 0°C and that SH control is possible. As a result, the control unit 50 performs SH control (step S92).

[0069] For example, the control unit 50 performs SH control by applying the MPC (Model Predictive Control) method to the linear state-space model of the refrigeration cycle represented by equations 2-1 and 2-2.

[0070]

number

[0071] Note that in equations 2-1 and 2-2, T E This is the evaporator temperature, i.e., the temperature of the outdoor heat exchanger 40 measured by the outdoor heat exchanger temperature sensor 59. Also, T C This is the condenser temperature, i.e., the temperature of the indoor heat exchanger 20 measured by the indoor heat exchanger temperature sensor 58. Furthermore, T S This is the temperature of the compressor inlet measured by the compressor inlet temperature sensor 56. C The compressor frequency is v φ This represents the opening degree of the expansion valve.

[0072] Also, in the MPC, every time a certain period of time elapses in the refrigeration cycle of the air conditioner 2, the temperature T of the evaporator E,k , the condenser temperature T C,k , and the temperature T at the compressor suction inlet S,k are detected, and an appropriate input u is searched for with the reference trajectory ysp,k of the output vector as the target for the period from the time when each temperature is detected to the horizon time pred. Also, in the MPC, appropriate values are set for the length of the horizon time pred and the reference trajectory y sp,k . Then, a reference trajectory y SH,K for which ΔT SH,K becomes ΔT = 0 within the control period is set. At this time, in the MPC, the cost function is defined by Equation 3-1, and u(k) represented by Equation 3-2, which minimizes the cost function at regular intervals, is obtained by a mathematical optimization method such as the QP method.

[0073]

Number

[0074] In step S92, such SH control is performed for a certain period of time. Then, after performing the SH control for a certain period of time, the superheat control process shown in FIG. 9 is terminated, and the process returns to step S of the power saving process shown in FIG. 8.

[0075] ​Here, the fixed time for performing SH control is preferably the operating time in the energy-saving state, which is assumed to be the time when the air conditioner 2 is operated in the energy-saving state when the energy-saving charge is calculated in step S5. For example, if the energy-saving charge is calculated in step S5 assuming that the air conditioner 2 is operated in the energy-saving state for the entire period from the present until the predicted period has elapsed, then the fixed time for performing SH control is preferably the time corresponding to that entire period. Also, if the energy-saving charge is calculated assuming that the air conditioner 2 is operated in the energy-saving state for only a portion of the entire period, then the fixed time for performing SH control is preferably the time corresponding to that portion of the period. Furthermore, if the energy-saving charge is calculated in step S5 assuming that the air conditioner 2 is operated in the energy-saving state only during a specific time period, then it is preferably the SH control is performed only during that specific time period.

[0076] Returning to Figure 9, if it is determined that the superheating degree SH is below a certain value (No. in step S91), the control unit 50 treats that the superheating degree SH is too close to 0°C to perform SH control. As a result, the control unit 50 terminates the superheat control process. Then, it returns to step S1 of the power saving process shown in Figure 8.

[0077] The power saving process continues until the power saving device 4 is stopped by pressing its activation switch (not shown) or until the air conditioner 2 is stopped by pressing its power button (not shown). As a result, the power saving system 1 continues to reduce the power consumption of the air conditioner 2 as long as either the power saving device 4 or the air conditioner 2 is running.

[0078] Furthermore, SH control, which aims to set the superheating degree SH to 0°C, refers to control that brings the superheating degree SH within a certain range from 0°C, for example, within a range of 0°C to less than 1°C. In other words, SH control can also be described as control that brings the superheating degree SH closer to 0°C. As is clear from this, SH control, which aims to set the superheating degree SH to 0°C, is an example of superheat control that brings the superheat closer to 0°C as described in this disclosure.

[0079] Furthermore, the control unit 50 of the air conditioner 2 is an example of an air conditioning control unit as defined in this disclosure. Or, it is an example of a control unit as defined in this disclosure. Operation of the air conditioner 2 by SH control is an example of energy-saving operation as defined in this disclosure. The power consumption of the air conditioner 2 when switched to an energy-saving state, predicted by the energy-saving charge calculation unit 15, i.e., the power consumption predicted in step S5, is an example of energy-saving power as defined in this disclosure. The energy-saving device 4 is an example of a control device as defined in this disclosure. The operating status data of each component of the air conditioner 2 is an example of operating status information of each component of the air conditioner as defined in this disclosure. Steps S1, S2, S3, S4 and S5 are examples of steps as defined in this disclosure, including steps to acquire electricity rate information, predict the trend of electricity rate, have the computer acquire operating status information of each component of the air conditioner, calculate the normal charge, and calculate the energy-saving charge. Furthermore, steps S6 and S7 are examples of steps in which the amount of money reduced by the energy saving as referred to in this disclosure is calculated, and it is determined that energy-saving operation should be performed if the calculated amount exceeds a set amount. In addition, steps S8 and S9 are examples of steps in which the computer instructs the control unit to operate each component of the air conditioner in an energy-saving state.

[0080] As described above, in the power saving system 1 and power saving device 4 according to the embodiment, the electricity rate forecasting unit 12 forecasts the trend of the unit price of electricity from the present until the forecast period has elapsed, and the normal rate calculation unit 14 and power saving rate calculation unit 15 calculate the normal rate and power saving rate based on the predicted trend of the unit price of electricity. In addition, the determination unit 16 determines the amount that will be reduced by power saving from the calculated normal rate and power saving rate, and determines that power saving operation should be performed if the determined amount exceeds a set amount. More specifically, it determines that SH control should be performed. For this reason, even when the unit price of electricity fluctuates according to the demand for electricity, the power saving system 1 and power saving device 4 can effectively save power by determining whether the amount that will be reduced by power saving exceeds a set amount. As a result, the power saving system 1 and power saving device 4 can perform sufficient power saving management.

[0081] (modified version) In this embodiment, the normal charge calculation unit 14, upon acquiring operating state data from the operating state information acquisition unit 13, calculates the normal charge for operating the air conditioner 2 under the conditions indicated by that operating state data. However, it is also possible to predict the operating state data from the present until the predicted period has elapsed based on the operating state data acquired from the operating state information acquisition unit 13. In this case, the normal charge calculation unit 14 may use, for example, an operating state prediction model based on a neural network trained with training data including the changes in the operating state of the air conditioner 2. The normal charge calculation unit 14 then uses the predicted operating state data from the present until the predicted period has elapsed to calculate the normal charge from the present until the predicted period has elapsed. This configuration allows for more effective energy saving.

[0082] Furthermore, in this embodiment, as an example of SH control, the refrigeration cycle of the air conditioner 2 is modeled using a linear time-invariant state-space model and controlled by the MPC. However, the control unit 50 may also perform SH control using a nonlinear state-space model.

[0083] The control method and program for the power saving system 1, power saving device 4, and air conditioner 2 according to the embodiments of this disclosure have been described above, but the control method and program for the power saving system 1, power saving device 4, and air conditioner 2 are not limited thereto.

[0084] For example, in this embodiment, the power saving device 4 includes an electricity rate information acquisition unit 11, an electricity rate forecasting unit 12, an operating status information acquisition unit 13, a normal rate calculation unit 14, a power saving rate calculation unit 15, a determination unit 16, and a command unit 17, but the power saving device 4 is not limited to this. The power saving device 4 only needs to include at least an electricity rate information acquisition unit 11, an electricity rate forecasting unit 12, an operating status information acquisition unit 13, a normal rate calculation unit 14, a power saving rate calculation unit 15, a determination unit 16, and a command unit 17. Therefore, as long as the power saving device 4 has these components, it may also have other components.

[0085] For example, if a business operator possessing the power saving system 1, power saving device 4, and program has a contract for negawatt trading with the electric utility operator operating the server 5, the power saving system 1 and power saving device 4 may further include a negawatt trading prediction unit. In that case, the negawatt trading prediction unit should predict whether or not negawatt trading will begin between the present and the end of the predicted period based on the unit price of electricity for a certain period acquired by the electricity rate information acquisition unit 11, and if negawatt trading will begin, it should also predict the start time and end time of the negawatt trading. Then, if the negawatt trading prediction unit predicts the start of negawatt trading and predicts the start time and end time, the determination unit 16 should determine that power saving operation should be performed after the time reaches the start time and after the end time, specifically that the air conditioner 2 should be operated using SH control. With such a configuration, power can be effectively saved during negawatt trading.

[0086] Furthermore, the air conditioner 2 may be equipped with a sensor to detect the location of a person if one is present in the vicinity, and a wind direction adjustment plate to adjust the airflow direction. In that case, the air conditioner 2 may be equipped with a drive unit that, upon receiving a power saving command signal, changes the direction of the wind direction adjustment plate to direct the airflow towards the location of the person detected by the sensor. With this configuration, the airflow can be directed towards people during power saving operation, thereby increasing comfort despite being in power saving mode.

[0087] In this embodiment, the control unit 50 determines whether SH control is possible by determining whether the superheating degree SH is above a certain value, but the control unit 50 is not limited to this. Determining whether SH control is possible is an optional process for the control unit 50, but the control unit 50 may, for example, determine that SH control is not possible if the refrigerant temperature TD at the outlet of the compressor 10, as measured by the compressor outlet temperature sensor 57, is within the set range for protecting the compressor 10. Alternatively, the control unit 50 may determine that SH control is not possible if the rotational speeds of the fans 21 and 41 are within the set range for protecting the compressor 10.

[0088] In the above embodiment, the control unit 50 of the air conditioner 2 performs SH control, but the air conditioner 2 is not limited to this. For example, the function of the control unit 50 that performs SH control may be provided in the power saving device 4. In this case, the power saving device 4 may perform SH control on each part of the air conditioner 2 via the network 100.

[0089] Furthermore, in the above embodiment, the power saving device 4 is a separate device from the air conditioner 2 and is connected to the air conditioner 2 via the network 100. However, the power saving device 4 is not limited to this. The power saving device 4 may be provided in the air conditioner 2. For example, the power saving device 4 may be provided inside the housing of the indoor unit of the air conditioner 2.

[0090] Furthermore, although the operation of the power saving system 1 was described in the above embodiment using the case where the air conditioner 2 is operating in heating mode as an example, it can also be applied when the air conditioner 2 is operating in cooling mode.

[0091] In the above embodiment, the power saving program and the superheat control program are stored in memories 46 and 52. However, the power saving program or the superheat control program may be stored and distributed on a computer-readable non-temporary recording medium such as a flexible disk, CD-ROM (Compact Disc Read-Only Memory), DVD (Digital Versatile Disc), or MO (Magneto-Optical Disc). In this case, the power saving program stored on the recording medium may be installed on a computer to configure the electricity rate information acquisition unit 11, electricity rate forecasting unit 12, operating status information acquisition unit 13, normal rate calculation unit 14, power saving rate calculation unit 15, determination unit 16, and command unit 17 that perform power saving processing. Alternatively, the superheat control program stored on the recording medium may be installed on a computer to configure the control unit 50 that performs superheat control processing.

[0092] Furthermore, the power saving program or superheat control program may be stored on a disk drive of a server device on a communication network such as the Internet, and these power saving programs or superheat control programs may be downloaded, for example, by being superimposed on a carrier wave. Alternatively, the power saving process or superheat control process described above may be achieved by starting and executing the power saving program or superheat control program while it is being transferred over the communication network. Furthermore, the power saving process or superheat control process described above may also be achieved by having all or part of the power saving program or superheat control program run on a server device, and by having a computer execute the program while sending and receiving information about the process over the communication network.

[0093] Furthermore, if the power saving process or superheat control process is implemented by each OS (Operating System), or through cooperation between the OS and the application, then only the parts other than the OS may be stored and distributed on a medium, or they may be downloaded. Also, the means for realizing the functions of the power saving device 4 and the control unit 50 are not limited to software, and some or all of them may be realized by dedicated hardware including circuits.

[0094] As described above, the control method and program for the power saving system 1, power saving device 4, and air conditioner 2 are not limited to the embodiments described above, and various modifications and substitutions can be made. Various forms of this disclosure are described below as appendices.

[0095] (Note 1) An energy-saving system comprising an air conditioner and a control device that manages energy saving by causing the air conditioner to perform energy-saving operation, The control device is An electricity rate information acquisition unit acquires electricity rate unit price information for a certain period including the present, An electricity rate forecasting unit predicts the trend of electricity rates from the present until the forecast period has elapsed, based on the electricity rate information acquisition unit for a certain period acquired by the electricity rate information acquisition unit, An operating status information acquisition unit that acquires information on the operating status of each component of the air conditioner from the control unit of the air conditioner, A normal charge calculation unit predicts the power consumption of the air conditioner from the operating status information acquired by the operating status information acquisition unit, and calculates the normal charge for operating the air conditioner in the operating status during the prediction period based on the predicted power consumption and the trend of the unit price of the electricity charge predicted by the electricity charge prediction unit. A power saving charge calculation unit predicts the amount of power saved when the air conditioner is operated in a power saving state based on the operating state information acquired by the operating state information acquisition unit, and calculates the power saving charge when the air conditioner is operated in a power saving state during the prediction period based on the predicted power saving and the trend of the unit price of the electricity charge predicted by the electricity charge prediction unit. A determination unit determines the amount that will be reduced by saving electricity from the normal charge calculated by the normal charge calculation unit and the electricity saving charge calculated by the electricity saving charge calculation unit, and determines that the electricity saving operation should be performed if the determined amount exceeds a set amount. When the determination unit determines that the power-saving operation should be performed, the air conditioning control unit operates each component of the air conditioner in the power-saving state, A power-saving system equipped with this feature. (Note 2) The aforementioned air conditioning control unit is the control unit provided in the air conditioner, The control device further includes a command unit that transmits a power saving command to the control unit when the determination unit determines that power saving operation should be performed. When the control unit receives the power saving command, it determines whether power saving operation is possible, and if power saving operation is possible, it operates each component of the air conditioner in the power saving state. The power saving system described in Appendix 1. (Note 3) The aforementioned power-saving operation is an operation using superheat control that brings the superheat temperature close to 0°C. The power saving system described in Appendix 2. (Note 4) The aforementioned air conditioner is A sensor that detects the location of a person if one is present in the vicinity, A wind direction adjustment plate for adjusting the wind direction, A drive unit that, upon receiving the aforementioned power saving command, changes the orientation of the wind direction adjustment plate to direct the wind towards the position of the person detected by the sensor, Equipped with, The power saving system described in Appendix 2 or 3. (Note 5) The control device is The system further includes a negawatt trading prediction unit that predicts whether or not negawatt trading will begin between the present and the end of the predicted period, based on the unit price of electricity for a certain period acquired by the electricity rate information acquisition unit, and predicts the start time and end time of the negawatt trading if such trading does begin. The determination unit determines, when the negawatt trading prediction unit predicts the start of the negawatt trading and predicts the start time and end time, that the power-saving operation should be performed after the start time and after the end time. A power-saving system described in any one of the appendices 1 through 4. (Note 6) The aforementioned electricity price forecasting unit uses a trained model that has learned the relationship between past electricity price trends and subsequent electricity price trends to predict the trend of electricity price trends from the present until the forecast period has elapsed. A power-saving system described in any one of the appendices 1 through 5. (Note 7) An energy-saving device that transmits an energy-saving command to a control unit of an air conditioner, causing the air conditioner to perform energy-saving operation, An electricity rate information acquisition unit acquires electricity rate unit price information for a certain period including the present, An electricity rate forecasting unit predicts the trend of electricity rates from the present until the forecast period has elapsed, based on the electricity rate information acquisition unit for a certain period acquired by the electricity rate information acquisition unit, An operating status information acquisition unit that acquires information on the operating status of each component of the air conditioner from the control unit of the air conditioner, A normal charge calculation unit predicts the power consumption of the air conditioner from the operating status information acquired by the operating status information acquisition unit, and calculates the normal charge for operating the air conditioner in the operating status during the prediction period based on the predicted power consumption and the trend of the unit price of the electricity charge predicted by the electricity charge prediction unit. A power saving charge calculation unit predicts the amount of power saved when the air conditioner is operated in a power saving state based on the operating state information acquired by the operating state information acquisition unit, and calculates the power saving charge when the air conditioner is operated in a power saving state during the prediction period based on the predicted power saving and the trend of the unit price of the electricity charge predicted by the electricity charge prediction unit. A determination unit determines the amount that will be reduced by saving electricity from the normal charge calculated by the normal charge calculation unit and the electricity saving charge calculated by the electricity saving charge calculation unit, and determines that the electricity saving operation should be performed if the determined amount exceeds a set amount. When the determination unit determines that the power-saving operation should be performed, a command unit transmits the power-saving command to the control unit, A power-saving device equipped with the following features. (Note 8) The computer that controls the control unit of the air conditioner obtains electricity rate information for a certain period, including the present. The computer predicts the trend of electricity rates from the present until the forecast period has elapsed, based on the electricity rate information for the aforementioned fixed period. The steps include: the computer acquiring information on the operating status of each component of the air conditioner from the control unit provided by the air conditioner; The steps include: predicting the power consumption of the air conditioner from the operating status information acquired by the computer, and calculating the normal charge for operating the air conditioner in the operating state during the prediction period based on the predicted power consumption and the predicted trend of the unit price of electricity; The steps include: predicting the amount of energy saved when the air conditioner is operated in an energy-saving state based on the operating status information acquired by the computer, and calculating the energy savings when the air conditioner is operated in an energy-saving state during the predicted period based on the predicted amount of energy saved and the predicted trend of the unit price of electricity; The steps include: determining the amount to be reduced by saving electricity from the normal charge calculated by the computer and the electricity saving charge calculated, and determining that electricity saving operation should be performed if the calculated amount exceeds a set amount; When it is determined that the power-saving operation should be performed, the computer instructs the control unit to operate each component of the air conditioner in the power-saving state, A control method for an air conditioner equipped with the following features. (Note 9) The computer that controls the control unit of the air conditioner, Steps to obtain unit price information for electricity rates for a certain period, including the present. A step of predicting the trend of electricity rates from the present until the forecast period has elapsed, based on the electricity rate unit price information obtained for the aforementioned fixed period. A step of obtaining information on the operating status of each component of the air conditioner from the control unit provided by the air conditioner. A step of predicting the power consumption of the air conditioner from the acquired operating status information, and calculating the normal charge for operating the air conditioner in the operating status during the prediction period based on the predicted power consumption and the predicted trend of the unit price of electricity. A step of predicting the amount of electricity saved when the air conditioner is operated in an energy-saving state based on the acquired operating state information, and calculating the amount of electricity saved when the air conditioner is operated in an energy-saving state during the prediction period based on the predicted amount of electricity saved and the predicted trend of the unit price of electricity. The steps include: determining the amount to be reduced by saving electricity from the calculated normal charge and the calculated electricity saving charge, and determining whether electricity saving operation should be performed if the calculated amount exceeds a set amount; and If the control unit determines that the power-saving operation should be performed, it transmits a command to each component of the air conditioner to the control unit to operate in the power-saving state. A program to execute.

[0096] This disclosure allows for various embodiments and modifications without departing from the broad spirit and scope of this disclosure. Furthermore, the embodiments described above are for illustrative purposes only and do not limit the scope of this disclosure. In other words, the scope of this disclosure is indicated by the claims, not by the embodiments. Various modifications made within the scope of the claims and the equivalent significance of the disclosure are considered to be within the scope of this disclosure.

[0097] This application is based on Japanese Patent Application No. 2022-195413, filed on 7 December 2022. The entire specification, claims, and drawings of Japanese Patent Application No. 2022-195413 are incorporated herein by reference. [Explanation of symbols]

[0098] 1 Power saving system, 2 Air conditioner, 3 Refrigerant circuit, 4 Power saving device, 5 Server, 10 Compressor, 11 Electricity charge information acquisition unit, 12 Electricity charge forecast unit, 13 Operating status information acquisition unit, 14 Normal charge calculation unit, 15 Power saving charge calculation unit, 16 Judgment unit, 17 Command unit, 20 Indoor heat exchanger, 21 Fan, 25 Charge forecast data storage unit, 26 Power consumption data storage unit, 27 Power saving data storage unit, 28 Parameter storage unit, 30 Expansion valve, 40 Outdoor heat exchanger, 41 Fan, 45 Processor, 46 Memory, 47 Network interface, 48 Bus, 50 Control unit, 51 Microprocessor, 52 Memory, 53 Network interface, 54 Bus, 55 Operating data storage unit, 56 Compressor inlet temperature sensor, 57 Compressor outlet temperature sensor, 58 Indoor heat exchanger temperature sensor, 59 Outdoor heat exchanger temperature sensor, 61 saturated liquid line, 62 saturated vapor line, 100 network, 110 electricity rate information, 111 power consumption information, 112 energy saving information.

Claims

1. An energy-saving device for causing an air conditioner to perform energy-saving operation, An electricity rate information acquisition unit acquires electricity rate unit price information for a certain period including the present, An electricity rate forecasting unit predicts the trend of electricity rates from the present until the forecast period has elapsed, based on the electricity rate information acquisition unit for a certain period of time acquired by the electricity rate information acquisition unit, An operating status information acquisition unit that acquires information on the operating status of each component of the air conditioner from the control unit of the air conditioner, A normal charge calculation unit calculates the normal charge when the air conditioner is operated in the operating state during the forecast period, based on the trend of the unit price of the electricity charge predicted by the electricity charge forecast unit. A power saving charge calculation unit predicts the amount of power saved when the air conditioner is operated in a power saving state based on the operating state information acquired by the operating state information acquisition unit, and calculates the power saving charge when the air conditioner is operated in a power saving state during the prediction period based on the predicted power saving and the trend of the unit price of the electricity charge predicted by the electricity charge prediction unit. A power-saving device equipped with the following features.

2. A determination unit that determines the amount to be reduced by saving electricity from the normal charge calculated by the normal charge calculation unit and the electricity saving charge calculated by the electricity saving charge calculation unit, and determines that the electricity saving operation should be performed if the determined amount exceeds a set amount, Furthermore, The power saving device according to claim 1.

3. A command unit that transmits a power saving command to the control unit when the determination unit determines that the power saving operation should be performed. Furthermore, The power saving device according to claim 2.

4. The normal charge calculation unit predicts the power consumption of the air conditioner from the operating state information acquired by the operating state information acquisition unit, and calculates the normal charge for operating the air conditioner in the operating state during the prediction period based on the predicted power consumption and the trend of the unit price of the electricity charge predicted by the electricity charge prediction unit. The power saving device according to claim 1 or 2.

5. The power saving device according to Claim 2, The aforementioned air conditioner, When the determination unit determines that the power-saving operation should be performed, the air conditioning control unit operates each component of the air conditioner in the power-saving state, Equipped with, The power saving device manages power saving by causing the air conditioner to perform power saving operation. Energy-saving system.

6. The aforementioned air conditioning control unit is the control unit provided in the air conditioner, The power saving device further includes a command unit that transmits a power saving command to the control unit when the determination unit determines that power saving operation should be performed. When the control unit receives the power saving command, it determines whether power saving operation is possible, and if power saving operation is possible, it operates each component of the air conditioner in the power saving state. The power saving system according to claim 5.

7. The aforementioned power-saving operation is an operation using superheat control that brings the superheat temperature close to 0°C. The power saving device according to any one of claims 1 to 3.

8. The aforementioned air conditioner is A sensor that detects the location of a person if one is present in the vicinity, A wind direction adjustment plate for adjusting the wind direction, A drive unit that, upon receiving the aforementioned power saving command, changes the orientation of the wind direction adjustment plate to direct the wind towards the position of the person detected by the sensor, Equipped with, The power saving system according to claim 6.

9. The system further comprises a negawatt trading prediction unit that predicts whether or not negawatt trading will begin between the present and the end of the predicted period based on the unit price of electricity for a certain period acquired by the electricity rate information acquisition unit, and, if negawatt trading begins, predicts the start time and end time of the negawatt trading. The power saving device according to claim 2.

10. The determination unit determines that, when the negawatt trading prediction unit predicts the start of the negawatt trading and predicts the start time and end time, the power saving operation should be performed after the time reaches the start time and after the end time. The power saving device according to claim 9.

11. The aforementioned electricity price forecasting unit uses a trained model that has learned the relationship between past electricity price trends and subsequent electricity price trends to predict the trend of electricity price trends from the present until the forecast period has elapsed. The power saving device according to any one of claims 1 to 3.

12. The computer that controls the control unit of the air conditioner obtains electricity rate information for a certain period, including the present. The computer predicts the trend of electricity rates from the present until the forecast period has elapsed, based on the electricity rate information for the aforementioned fixed period. The steps include: the computer acquiring information on the operating status of each component of the air conditioner from the control unit provided by the air conditioner; A step of calculating the normal charge when the air conditioner is operated in the operating state during the forecast period based on the predicted trend of the unit price of electricity, The steps include: predicting the amount of energy saved when the air conditioner is operated in an energy-saving state based on the operating status information acquired by the computer, and calculating the energy savings when the air conditioner is operated in an energy-saving state during the predicted period based on the predicted amount of energy saved and the predicted trend of the unit price of electricity; A control method for an air conditioner equipped with the following features.

13. The computer further comprises the step of determining the amount to be reduced by saving electricity from the normal charge calculated by the computer and the electricity saving charge calculated, and determining that electricity saving operation should be performed if the amount determined exceeds a set amount. The control method for an air conditioner according to claim 12.

14. When the control unit determines that the power-saving operation should be performed, the computer further provides a step instructing the control unit to operate each component of the air conditioner in the power-saving state. A method for controlling an air conditioner according to claim 13.

15. The computer that controls the control unit of the air conditioner, Steps to obtain unit price information for electricity rates for a certain period, including the present. A step of predicting the trend of electricity rates from the present until the forecast period has elapsed, based on the electricity rate unit price information obtained for the aforementioned fixed period. A step of obtaining information on the operating status of each component of the air conditioner from the control unit provided by the air conditioner. A step of calculating the normal charge when the air conditioner is operated in the operating state during the predicted period based on the predicted trend of the unit price of electricity, and, The steps include: predicting the amount of electricity saved when the air conditioner is operated in an energy-saving state based on the acquired operating state information; calculating the electricity cost saved when the air conditioner is operated in an energy-saving state during the predicted period based on the predicted amount of electricity saved and the predicted trend of the unit price of electricity; A program to execute.

16. The system further comprises the steps of determining the amount to be reduced by saving electricity from the calculated normal charge and the calculated electricity saving charge, and determining that electricity saving operation should be performed if the calculated amount exceeds a set amount. The program according to claim 15.

17. When it is determined that the power-saving operation should be performed, the control unit further comprises the step of transmitting a command to each component of the air conditioner to the control unit to operate in the power-saving state. L as described in claim 16.

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