Air conditioner

Abstract

This air conditioner (1) comprises a compressor (12) and a controller (C) that controls the compressor (12). The controller (C) can implement a first mode for controlling the rotational speed of the compressor (12) such that an air conditioning capacity value is less than or equal to an upper limit value. The first mode is a mode in which the air conditioning capacity value during a state in which a condition has been realized is set as a reference capacity value, said condition being that the difference between the indoor temperature and a target temperature is less than or equal to a first prescribed value, and a first value that is lower than the reference capacity value is set as the upper limit value.

Description

air conditioning equipment

[0001] The present disclosure relates to an air conditioning apparatus.

[0002] Patent Document 1 discloses an air conditioner equipped with a control unit that controls the compressor current so that it is equal to or less than a current threshold. In the air conditioner described in Patent Document 1, the current threshold is set based on the design maximum value of the current.

[0003] Patent Publication No. 2021-124228

[0004] As described in Patent Document 1, setting an upper limit on the current supplied to the compressor can suppress deterioration in the power consumption rate and is expected to have an energy-saving effect. However, if the current threshold is too small, the air conditioning performance cannot be fully demonstrated. Conversely, if the current threshold is too large, the current rarely reaches the current threshold, resulting in a small energy-saving effect.

[0005] The present disclosure aims to achieve both air conditioning performance and energy saving effects.

[0006] A first aspect is directed to an air conditioner capable of at least one of cooling operation and heating operation. The air conditioner includes a compressor (12) and a controller (C) that controls the compressor (12). The controller (C) is capable of executing a first mode in which the rotation speed of the compressor (12) is controlled so that the air conditioning capacity value is equal to or less than an upper limit value, and the first mode is a mode in which the air conditioning capacity value in a state where a condition is met in which the difference between the room temperature and the target temperature is equal to or less than a first predetermined value is set as a reference capacity value, and a first value lower than the reference capacity value is set as the upper limit value.

[0007] In the first aspect, the compressor (12) can be operated at a high rotational speed until the room temperature approaches a target temperature, thereby enabling sufficient air conditioning performance. On the other hand, when the room temperature approaches the target temperature, the air conditioning load is relatively low, and therefore the rotational speed of the compressor (12) may be low. By reducing the rotational speed of the compressor (12) so as to keep the air conditioning capacity value even lower than the reference capacity value, it is possible to enhance the energy saving effect. Therefore, it is possible to achieve both high air conditioning performance and energy saving effect.

[0008] In a second aspect, in the first aspect, the first value is a variable value that varies based on the reference ability value.

[0009] For example, when the difference between the outside air temperature and the target temperature is large, the air conditioning capacity value is likely to be higher than when the difference is small, even if the target temperature is the same. By setting the first value to a variable value as in the second aspect, it is possible to fully demonstrate air conditioning performance while also increasing energy-saving effects.

[0010] In a third aspect, in the second aspect, the first value is higher when the air conditioning load is high than when the air conditioning load is low.

[0011] For example, when the indoor temperature is higher than the target temperature during cooling operation, or when the indoor temperature is lower than the target temperature during heating operation, the air conditioning load increases. As in the third aspect, by increasing the first value when the air conditioning load is high, it is possible to fully demonstrate the air conditioning performance. On the other hand, by reducing the first value as much as possible when the air conditioning load is low, it is possible to obtain a high energy-saving effect.

[0012] In a fourth aspect, in the third aspect, when the air conditioning load becomes high, the controller (C) changes the upper limit value to a second value higher than the first value, and controls the rotation speed of the compressor (12).

[0013] In the fourth aspect, by changing the upper limit value to the second value when the air conditioning load is high, the rotation speed of the compressor (12) can be increased, and the air conditioning performance can be fully exhibited.

[0014] In a fifth aspect, in the fourth aspect, when the air conditioning load is low, the controller (C) changes the upper limit value to a third value lower than the second value, and controls the rotation speed of the compressor (12).

[0015] In the fifth aspect, by changing the upper limit value to the third value when the air conditioning load is low, it is possible to improve the energy saving effect.

[0016] In a sixth aspect, in any one of the first to fifth aspects, when the indoor temperature remains equal to or lower than the target temperature for a predetermined period of time or longer during the cooling operation, or when the indoor temperature remains equal to or higher than the target temperature for a predetermined period of time or longer during the cooling operation, the controller (C) changes the upper limit value to a fourth value that is lower than the first value, and controls the rotation speed of the compressor (12).

[0017] For example, if the indoor temperature remains below the target temperature for a predetermined period of time during cooling operation, the indoor temperature can be maintained near the target temperature even if the air conditioning capacity value is further reduced, unless the external environment changes significantly. In such a situation, if the upper limit is further tightened, as in the sixth aspect, the energy saving effect can be further increased.

[0018] A seventh aspect is the first aspect, wherein the first value is a value that varies depending on a setting by a user.

[0019] In the seventh aspect, the user controls the upper limit value by himself, thereby achieving an energy-saving effect and suppressing a decrease in user comfort.

[0020] In an eighth aspect, in any one of the first to seventh aspects, when a predetermined thermo-off condition is satisfied, the controller (C) stops the compressor (12) and resets the reference capacity value and the upper limit value, and when the state changes from a state in which the thermo-off condition is satisfied to a state in which the thermo-off condition is not satisfied, the controller (C) operates the compressor (12) and resets the reference capacity value and the first value based on the air conditioning capacity value after the state in which the thermo-off condition is not satisfied, and controls the rotation speed of the compressor (12) using the reset first value as the upper limit value.

[0021] When the compressor (12) is temporarily stopped and then restarted, there is a high possibility that the required air conditioning capacity value will change from that before the compressor (12) was stopped. As in the eighth aspect, after the compressor (12) is temporarily stopped, the reference capacity value and the first value are reset based on the air conditioning capacity value after the compressor (12) is restarted, thereby making it possible to control the compressor (12) so that the air conditioning performance is easily exerted and the energy saving effect is enhanced.

[0022] In a ninth aspect, in any one of the first to eighth aspects, when the target temperature is changed to a lower temperature during the cooling operation or when the target temperature is changed to a higher temperature during the heating operation, the controller (C) resets the standard capacity value and the upper limit value, and resets the standard capacity value and the first value based on the air conditioning capacity value in a state where a condition is met in which the difference between the indoor temperature and the changed target temperature is equal to or less than a predetermined value, and controls the rotation speed of the compressor (12) using the reset first value as the upper limit value.

[0023] In the ninth aspect, for example, when the target temperature is changed to a lower temperature during cooling operation, the rotation speed of the compressor (12) can be increased by resetting the reference capacity value and the upper limit value. If the rotation speed of the compressor (12) can be increased, the changed target temperature can be reached more quickly. When the room temperature approaches the target temperature, the reference capacity value and the first value can be reset to reduce the rotation speed of the compressor, thereby increasing the energy saving effect.

[0024] In a tenth aspect, in any one of the first to ninth aspects, the controller (C) interrupts the first mode when, during the cooling operation, the indoor temperature becomes higher than the target temperature by a second predetermined value that is greater than the first predetermined value, or when, during the heating operation, the indoor temperature becomes lower than the target temperature by the second predetermined value or more.

[0025] When the deviation from the target temperature is large, it is necessary to operate the air conditioner at the highest possible air conditioning capacity value so as to quickly reach the target temperature. By interrupting the first mode as in the tenth aspect, the target temperature can be reached quickly, thereby improving user comfort.

[0026] In an eleventh aspect, in any one of the first to tenth aspects, the controller (C) interrupts the first mode when the indoor temperature becomes equal to or higher than a first predetermined temperature during the cooling operation, or when the indoor temperature becomes equal to or lower than a second target temperature that is lower than the first predetermined temperature during the heating operation, while the first mode is being executed.

[0027] In the eleventh aspect, when the indoor temperature is too high or too low, the first mode is interrupted and the air conditioner is operated at the highest possible air conditioning capacity value, thereby maintaining the indoor temperature at an appropriate temperature, thereby improving user comfort.

[0028] A twelfth aspect is any one of the first to eleventh aspects, wherein the air conditioning capacity value is the amount of power consumed by the air conditioner.

[0029] In the twelfth aspect, the amount of power consumption that is directly related to energy saving is used as the air conditioning capacity value, and an upper limit value is set when the indoor temperature is close to the target temperature, thereby making it possible to expect a high energy saving effect in the first mode.

[0030] FIG. 1 is a schematic diagram of the overall configuration of an air conditioner according to an embodiment. FIG. 2 is a diagram showing the refrigerant piping and air flow of the air conditioner. FIG. 3 is a longitudinal cross-sectional view of an air conditioning indoor unit. FIG. 4 is a block diagram including major elements of the air conditioner. FIG. 5 is a diagram showing the electrical wiring connections of the air conditioner. FIG. 6 is a part of a flowchart showing the processing operation of a controller in energy-saving mode during cooling operation. FIG. 7 is a part of a flowchart showing the processing operation of a controller in energy-saving mode during cooling operation. FIG. 8 is the remaining part of a flowchart showing the processing operation of a controller in energy-saving mode during cooling operation. FIG. 9 is a part of a flowchart showing the processing operation of a controller in energy-saving mode during heating operation. FIG. 10 is a part of a flowchart showing the processing operation of a controller in energy-saving mode during heating operation. FIG. 11 is the remaining part of a flowchart showing the processing operation of a controller in energy-saving mode during heating operation. FIG. 12 is an example of a time chart showing the relationship between indoor temperature, power consumption, and air-conditioning load in energy-saving mode during cooling operation. FIG. 13 is another example of a time chart showing the relationship between indoor temperature, power consumption, and air-conditioning load in energy-saving mode during cooling operation.

[0031] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. Note that the present disclosure is not limited to the embodiments shown below, and various modifications are possible within the scope of the technical concept of the present disclosure. Since the drawings are intended to conceptually explain the present disclosure, dimensions, ratios, or numbers may be exaggerated or simplified as necessary to facilitate understanding.

[0032] Exemplary embodiments will now be described in detail with reference to the accompanying drawings.

[0033] (1) Overview of the Air Conditioner Configuration The air conditioner (1) adjusts the temperature and humidity of air in a room (I). As shown in FIG. 1 , the air conditioner (1) has an air conditioning outdoor unit (10) and an air conditioning indoor unit (30). The air conditioning outdoor unit (10) is installed outdoors, and the air conditioning indoor unit (30) is installed indoors. The air conditioner (1) is a pair type having one air conditioning indoor unit (30) and one air conditioning outdoor unit (10). The air conditioner (1) has the function of humidifying and dehumidifying air. The air conditioner (1) also has the function of ventilating the room (I).

[0034] The air conditioner (1) has a humidity control unit (20) and an air conditioning unit (5). The humidity control unit (20) controls the humidity of the room (I), which is the target space. Strictly speaking, the humidity control unit (20) constitutes a humidification unit for humidifying the room air. In addition, the humidity control unit (20) also serves as a dehumidification unit for dehumidifying the room air. The air conditioning unit (5) controls the temperature of the air in the room (I), which is the target space. Strictly speaking, the air conditioning unit (5) heats and cools the room air.

[0035] As shown in Figures 1 and 2, the air conditioner (1) has a hose (2), a liquid connection pipe (3), and a gas connection pipe (4). The air conditioning indoor unit (30) and the humidity control unit (20) are connected to each other via the hose (2). The air conditioning indoor unit (30) and the air conditioning outdoor unit (10) are connected to each other via the liquid connection pipe (3) and the gas connection pipe (4), and a refrigerant circuit (R) is filled with a refrigerant. The refrigerant is difluoromethane. However, the refrigerant is not limited to difluoromethane. The refrigerant circuit (R) performs a vapor compression refrigeration cycle.

[0036] The refrigerant circuit (R) mainly includes a compressor (12), an outdoor heat exchanger (14), an expansion valve (15), a four-way switching valve (16), and an indoor heat exchanger (34).

[0037] The refrigerant circuit (R) operates in a first refrigeration cycle or a second refrigeration cycle in response to switching of the four-way selector valve (16). The first refrigeration cycle is a refrigeration cycle in which the indoor heat exchanger (34) functions as an evaporator and the outdoor heat exchanger (14) functions as a radiator. The second refrigeration cycle is a refrigeration cycle in which the indoor heat exchanger (34) functions as a radiator and the outdoor heat exchanger (14) functions as an evaporator.

[0038] (2) Detailed Configuration (2-1) Air Conditioning Outdoor Unit As shown in Figures 2 and 4, the air conditioning outdoor unit (10) has an outdoor casing (11), a compressor (12), an outdoor fan (13), an outdoor heat exchanger (14), an expansion valve (15), and a four-way switching valve (16).

[0039] A partition plate (18) is provided inside the outdoor casing (11). The partition plate (18) divides the interior of the outdoor casing (11) into a first space (S1) and a second space (S2). The first space (S1) is provided with a compressor (12) and an outdoor heat exchanger (14). Strictly speaking, the first space (S1) is provided with the compressor (12), the outdoor fan (13), the outdoor heat exchanger (14), an expansion valve (15), and a four-way selector valve (16). The outdoor casing (11) is formed with an outdoor suction port (11a), an outdoor outlet (11b), a moisture absorption side suction port (61a), and a moisture absorption side exhaust port (61b). The outdoor suction port (11a) is formed on the rear side of the outdoor casing (11). The outdoor inlet (11a) is an opening for drawing in outdoor air (outdoor air). The outdoor outlet (11b) is formed on the front side of the outdoor casing (11). The outdoor outlet (11b) is an opening for blowing out air that has passed through the outdoor heat exchanger (14). An outdoor air passage (11c) is formed inside the outdoor casing (11) from the outdoor inlet (11a) to the outdoor outlet (11b).

[0040] The compressor (12) draws in and compresses low-pressure gas refrigerant. The compressor (12) is driven by a first motor (M1). The compressor (12) is a variable-capacity compressor in which power is supplied to the first motor (M1) from an inverter circuit. The compressor (12) is configured so that its operating capacity can be changed by adjusting the operating frequency (rotation speed) of the first motor (M1). The compressor (12) is a so-called high-pressure dome type compressor in which the interior is filled with high-pressure refrigerant. During operation, heat generated by the compressor (12) is released to the surroundings. The power consumed by the compressor (12) depends on the rotation speed of the first motor (M1). Specifically, the power consumption is higher when the rotation speed of the first motor (M1) is high than when the rotation speed is low. In the following description, the term "rotation speed of the compressor (12)" refers to the rotation speed of the first motor (M1).

[0041] The outdoor fan (13) is disposed in the outdoor air passage (11c). The outdoor fan (13) is rotated by being driven by the second motor (M2). Air transported by the outdoor fan (13) is sucked into the outdoor casing (11) through the outdoor inlet (11a). This air flows through the outdoor air passage (11c) and is blown out of the outdoor casing (11) through the outdoor outlet (11b). The outdoor fan (13) transports the outdoor air so that it passes through the outdoor heat exchanger (14).

[0042] The outdoor heat exchanger (14) is disposed in the outdoor air passage (11c) upstream of the outdoor fan (13). In this example, the outdoor heat exchanger (14) is a fin-and-tube heat exchanger. The outdoor heat exchanger (14) exchanges heat between the refrigerant flowing therethrough and the outdoor air transported by the outdoor fan (13).

[0043] The expansion valve (15) reduces the pressure of the refrigerant. The expansion valve (15) is an electrically operated expansion valve whose opening is adjustable. The pressure reducing mechanism may be a temperature-sensitive expansion valve, an expander, a capillary tube, or the like. The expansion valve (15) may be connected to the liquid line of the refrigerant circuit (R), and may be provided in the air conditioning indoor unit (30).

[0044] The four-way selector valve (16) has a first port (P1), a second port (P2), a third port (P3), and a fourth port (P4). The first port (P1) is connected to the discharge port of the compressor (12). The second port (P2) is connected to the suction port of the compressor (12). The third port (P3) is connected to the gas end of the outdoor heat exchanger (14). The fourth port (P4) is connected to the gas connecting pipe (4).

[0045] The four-way selector valve (16) can be switched between a first state (shown by a solid line in FIG. 2 ) and a second state (shown by a dashed line in FIG. 2 ). In the first state, the four-way selector valve (16) connects the first port (P1) to the third port (P3) and connects the second port (P2) to the fourth port (P4). In the second state, the four-way selector valve (16) connects the first port (P1) to the fourth port (P4) and connects the second port (P2) to the third port (P3).

[0046] (2-2) Air Conditioning Indoor Unit As shown in Figures 1 to 3, the air conditioning indoor unit (30) is installed indoors. The air conditioning indoor unit (30) is a wall-mounted type that is installed on the wall (WL) of a room that forms the room (I). The air conditioning indoor unit (30) has an indoor casing (31), an indoor fan (32), an air filter (33), an indoor heat exchanger (34) that is a heat utilization exchanger, a drain pan (35), and an air direction adjustment unit (36).

[0047] The indoor casing (31) accommodates the indoor fan (32), the air filter (33), the indoor heat exchanger (34), and the drain pan (35). The indoor casing (31) is formed with an indoor air inlet (31a) and an indoor air outlet (31b). The indoor air inlet (31a) is located on the upper side of the indoor casing (31). The indoor air inlet (31a) is an opening for drawing in indoor air. The indoor air outlet (31b) is located on the lower side of the indoor casing (31). The indoor air outlet (31b) is an opening for blowing out air after heat exchange or air for humidity control. An indoor air passage (31c) extending from the indoor air inlet (31a) to the indoor air outlet (31b) is provided inside the indoor casing (31).

[0048] The indoor fan (32) is disposed approximately in the center of the indoor air passage (31c). The indoor fan (32) is, for example, a cross-flow fan. The indoor fan (32) is rotated by the fifth motor (M5). The indoor fan (32) takes in indoor air into the indoor air passage (31c) and transports it. The air transported by the indoor fan (32) is sucked into the indoor casing (31) through the indoor inlet (31a). This air flows through the indoor air passage (31c) and is blown out of the indoor casing (31) through the indoor outlet (31b).

[0049] The indoor fan (32) transports indoor air so that the air passes through the indoor heat exchanger (34). The air blown out through the indoor outlet (31b) is supplied to the room (I). The indoor fan (32) is configured so that the air volume can be switched between a plurality of levels by adjusting the rotation speed of the fifth motor (M5).

[0050] The air filter (33) is disposed in the indoor air passage (31c) upstream of the indoor heat exchanger (34). The air filter (33) is attached to the indoor casing (31) so that substantially all of the air supplied to the indoor heat exchanger (34) passes through the air filter (33). The air filter (33) collects dust in the air sucked through the indoor air inlet (31a).

[0051] The indoor heat exchanger (34) is disposed in the indoor air passage (31c) upstream of the indoor fan (32). In this example, the indoor heat exchanger (34) is a fin-and-tube heat exchanger. The indoor heat exchanger (34) exchanges heat between the refrigerant therein and the indoor air transported by the indoor fan (32).

[0052] The drain pans (35) are disposed below the front and rear of the indoor heat exchanger (34). The drain pans (35) receive condensation water generated inside the indoor casing (31) of the air conditioning indoor unit (30). The condensation water generated on the surfaces of the fins of the indoor heat exchanger (34) flows down along the surfaces due to its own weight and is received in the drain pan (35).

[0053] The airflow direction adjuster (36) adjusts the direction of air blown out from the indoor air outlet (31b). The airflow direction adjuster (36) has a flap (37). The flap (37) is formed in the shape of a long plate extending along the longitudinal direction of the indoor air outlet (31b). The flap (37) is rotated by the driving of a motor. The flap (37) opens and closes the indoor air outlet (31b) as it rotates.

[0054] The flap (37) is configured so that the inclination angle can be changed in stages. In this example, the positions to which the flap (37) can be adjusted include six positions. These six positions include a closed position and five open positions. The five open positions include the substantially horizontal blowing position shown in FIG. 3. The flap (37) in the closed position substantially closes the indoor blowing outlet (31b). A gap may be formed between the flap (37) in the closed position and the indoor blowing outlet (31b).

[0055] (2-3) Remote Controller As shown in FIGS. 2 and 4, the air conditioner (1) includes a remote controller (40). The remote controller (40) is placed in a position in the room where the user can operate it. The remote controller (40) has a display unit (41) and an input unit (42). The display unit (41) displays predetermined information. The display unit (41) is configured, for example, by a liquid crystal monitor. The predetermined information is information indicating the operating state and set temperature of the air conditioner (1). The input unit (42) accepts input operations from the user to make various settings. The input unit (42) is configured, for example, by a plurality of physical switches. The user can set the operating mode, target temperature, target humidity, etc. of the air conditioner (1) by operating the input unit (42) of the remote controller (40).

[0056] (2-4) Sensors As shown in Figures 2 and 4, the air conditioner (1) has a plurality of sensors. The plurality of sensors includes a sensor for the refrigerant and a sensor for the air. The refrigerant sensors include a sensor for detecting the temperature and pressure of a high-pressure refrigerant and a sensor for detecting the temperature and pressure of a low-pressure refrigerant (not shown).

[0057] The air sensors include an outdoor air temperature sensor (51), an indoor air temperature sensor (53), and an indoor air humidity sensor (54). The outdoor air temperature sensor (51) is provided in the air conditioner outdoor unit (10). The outdoor air temperature sensor (51) detects the temperature of the outdoor air. The indoor air temperature sensor (53) and the indoor air humidity sensor (54) are provided in the air conditioner indoor unit (30). The indoor air temperature sensor (53) detects the temperature of the indoor air. The indoor air humidity sensor (54) detects the humidity of the indoor air. The indoor air humidity sensor (54) detects the relative humidity of the indoor air, but may also detect the absolute humidity. (2-5) Controller As shown in FIGS. 2 and 4, the air conditioner (1) has a controller (C). The controller (C) controls the operation of the refrigerant circuit (R). The controller (C) controls the operation of the air conditioner outdoor unit (10), the humidity control unit (20), and the air conditioner indoor unit (30). The controller (C) includes an outdoor control unit (OC), an indoor control unit (IC), and a remote controller (40). The outdoor control unit (OC) is provided in the air conditioning outdoor unit (10). The indoor control unit (IC) is provided in the air conditioning indoor unit (30). Each of the indoor control unit (IC) and the outdoor control unit (OC) includes an MCU (Micro Control Unit), an electric circuit, and an electronic circuit. The MCU includes a CPU (Central Processing Unit), a memory, and a communication interface. The memory stores various programs to be executed by the CPU.

[0058] The outdoor control section (OC) receives a detection value of the outdoor air temperature sensor (51).

[0059] The outdoor control unit (OC) is connected to the compressor (12), the outdoor fan (13), the expansion valve (15), and the four-way switching valve (16). The outdoor control unit (OC) outputs control signals to the compressor (12), the outdoor fan (13), the expansion valve (15), and the four-way switching valve (16) to start and stop the operation of the air conditioning outdoor unit (10). The outdoor control unit (OC) controls the rotation speed of the first motor (M1) of the compressor (12), the rotation speed of the second motor (M2) of the outdoor fan (13), the state of the four-way switching valve (16), and the opening of the expansion valve (15).

[0060] The indoor control unit (IC) receives the detected values ​​of the room air temperature sensor (53) and the detected values ​​of the room air humidity sensor (54).

[0061] The indoor control unit (IC) is connected to the remote controller (40) so as to be able to communicate with the indoor control unit (IC). The indoor control unit (IC) is connected to the indoor fan (32). The indoor control unit (IC) outputs a control signal to the indoor fan (32) for starting and stopping the operation of the air conditioning indoor unit (30). The indoor control unit (IC) controls the rotation speed of a fifth motor (M5) of the indoor fan (32). The indoor control unit (IC) is connected to the outdoor control unit (OC) so as to be able to communicate with the outdoor control unit (OC).

[0062] The remote controller (40) is communicably connected to the indoor control unit (IC). The remote controller (40) transmits an instruction signal to the indoor control unit (IC) instructing the operation of the air conditioner (1) in response to a user's operation on the input unit (42). Upon receiving the instruction signal from the remote controller (40), the indoor control unit (IC) transmits the instruction signal to the outdoor control unit (OC). The indoor control unit (IC) controls the operation of the above-mentioned devices of the air conditioning indoor unit (30) in accordance with the instruction signal. Upon receiving the instruction signal from the indoor control unit (IC), the outdoor control unit (OC) controls the operation of the above-mentioned devices of the air conditioning outdoor unit (10) and the humidity control unit (20).

[0063] (3) Operational Modes The air conditioner (1) can perform include cooling operation, heating operation, air supply operation, exhaust operation, dehumidification operation, humidification operation, dehumidification-cooling operation, and heating-humidification operation. The controller (C) executes these operations based on command signals from the remote controller (40).

[0064] (3-1) Cooling Operation Cooling operation is an operation in which indoor air is cooled by the indoor heat exchanger (34) functioning as an evaporator. The humidity control unit (20) is stopped. In cooling operation, the controller (C) operates the compressor (12), the outdoor fan (13), and the indoor fan (32). The controller (C) sets the four-way switching valve (16) to the first state. The controller (C) appropriately adjusts the opening of the expansion valve (15). In cooling operation, a first refrigeration cycle is performed in which compressed refrigerant releases heat in the outdoor heat exchanger (14) and evaporates in the indoor heat exchanger (34).

[0065] In the cooling operation, the rotation speed of the compressor (12) is controlled so that the indoor temperature detected by the indoor air temperature sensor (53) converges to a target temperature. The target temperature is, for example, a set temperature set by the remote controller (40). In the cooling operation, air transported by the indoor fan (32) is cooled as it passes through the indoor heat exchanger (34). The air cooled by the indoor heat exchanger (34) is supplied to the room (I) through the indoor outlet (31b) of the air conditioner indoor unit (30).

[0066] (3-2) Heating Operation Heating operation is an operation in which indoor air is heated by the indoor heat exchanger (34) functioning as a radiator. The humidity control unit (20) is stopped. In heating operation, the controller (C) operates the compressor (12), the outdoor fan (13), and the indoor fan (32). The controller (C) sets the four-way switching valve (16) to the second state. The controller (C) appropriately adjusts the opening of the expansion valve (15). In heating operation, a second refrigeration cycle is performed in which refrigerant compressed by the compressor (12) radiates heat in the indoor heat exchanger (34) and evaporates in the outdoor heat exchanger (14).

[0067] In the heating operation, the rotation speed of the compressor (12) is controlled so that the indoor temperature detected by the indoor air temperature sensor (53) converges to a target temperature. The target temperature is, for example, a set temperature set by the remote controller (40). In the heating operation, air transported by the indoor fan (32) is heated as it passes through the indoor heat exchanger (34). The air heated in the indoor heat exchanger (34) is supplied to the room (I) through the indoor outlet (31b) of the air conditioner indoor unit (30).

[0068] (4) Electrical Wiring of Air Conditioner The air conditioner (1) is connected to a commercial power source (E). As shown in Fig. 5, the humidity control unit (20) has a humidity control rotor (22), a first fan (26), a second fan (23), a heater (25), a first switching damper (24), and a second switching damper (29). The air conditioning unit (5) has the above-mentioned compressor (12), outdoor fan (13), expansion valve (15), four-way switching valve (16), outdoor air temperature sensor (51), indoor fan (32), air direction adjustment unit (36), indoor air temperature sensor (53), and indoor air humidity sensor (54).

[0069] The air conditioning outdoor unit (10) is provided with a first relay terminal (71) electrically connected to each device on the air conditioning outdoor unit (10) side. The air conditioning indoor unit (30) is provided with a second relay terminal (72) electrically connected to each device on the air conditioning indoor unit (30) side. The first relay terminal (71) and the second relay terminal (72) are connected to each other via a relay electrical wiring (73). The electrical wiring of the air conditioning indoor unit (30) is connected to a commercial power source (E), for example, by inserting a power plug (74) into an outlet (75) in the room (I). As a result, the humidity control unit (20) and the air conditioning unit (5) are connected to the commercial power source (E) via a breaker (B).

[0070] The breaker (B) is a molded case circuit breaker. The breaker (B) is, for example, a molded case circuit breaker (MCCB). The breaker (B) electrically cuts off the connection between the commercial power source (E) and the electrical equipment, including the air conditioner (1), when the current value from the commercial power source (E) to the electrical equipment exceeds a predetermined value.

[0071] (5) Details of Control by Controller During cooling operation, the controller (C) increases the rotation speed (operating frequency) of the compressor (12) when the room temperature is significantly higher than the target temperature, and decreases the rotation speed of the compressor (12) when the room temperature approaches the target temperature. During heating operation, the controller (C) increases the rotation speed of the compressor (12) when the room temperature is significantly lower than the target temperature, and decreases the rotation speed of the compressor (12) when the room temperature approaches the target temperature. When the rotation speed of the compressor (12) is high, the power consumption of the compressor (12) is high. Because the proportion of the power consumption of the compressor (12) in the total power consumption of the air conditioner (1) is significantly large, the power consumption of the compressor (12) has a large impact on the total power consumption of the air conditioner (1). In order to reduce power consumption, the controller (C) sets a maximum upper limit of power consumption based on the rated current of the compressor (12), etc., and controls the compressor (12) so that power consumption does not exceed the maximum upper limit when the compressor (12) is rotating at a high speed. If this maximum upper limit is too low, the air conditioner (1) will not be able to fully demonstrate its air conditioning performance, and it will take a long time for the indoor temperature to approach the target temperature. On the other hand, even if the maximum upper limit is set appropriately, if the indoor temperature remains close to the target temperature for a long period of time, the power consumption will hardly reach the maximum upper limit, and sufficient energy saving effects will not be achieved.

[0072] To solve this problem, the controller (C) causes the air conditioner (1) to operate in an energy-saving mode in which the rotation speed of the compressor (12) is reduced when the difference between the room temperature and the target temperature is small. The energy-saving mode will be described in detail below. In this embodiment, the energy-saving mode corresponds to the first mode.

[0073] (5-1) Overview of Energy-Saving Mode The energy-saving mode is a control mode for obtaining a sufficient energy-saving effect when the room temperature is close to the target temperature and the rotation speed of the compressor (12) is relatively low. The controller (C) controls the temperature control unit (14) to control the temperature control unit (14) when the difference (ΔT) between the room temperature and the target temperature is equal to or smaller than a first predetermined value (ΔT C1 ) continues for a first predetermined time. Specifically, when the difference (ΔT) between the room temperature and the target temperature reaches a first predetermined value (ΔT C1When a state of not more than the first predetermined value (ΔT ) continues for a first predetermined time, the controller (C) sets the power consumption at the time of the first predetermined time lapse as a reference capacity value. The controller (C) sets a first value lower than the reference capacity value as a set upper limit value. The controller (C) controls the rotation speed of the compressor (12) so that the power consumption becomes not more than the first value. C1 ) is, for example, 0.5°C. The first predetermined time is, for example, 5 minutes. When the difference (ΔT) between the room temperature and the target temperature is equal to or greater than the first predetermined value (ΔT C1 ) The following states include a state in which the indoor temperature is higher than the target temperature by a first predetermined value during cooling operation, and a state in which the indoor temperature is lower than the target temperature by a first predetermined value during heating operation. Power consumption is an example of an air conditioning capacity value.

[0074] The controller (C) sets a first value according to the reference ability value. That is, the first value is a variable value that changes according to the reference ability value. The controller (C) calculates the first value, for example, by multiplying the reference ability value by a coefficient less than 1 (such as 0.8 or 0.9).

[0075] The user can select whether to operate the air conditioner (1) in energy-saving mode. The remote controller (40) has a selection button for selecting whether to execute the energy-saving mode. When the selection button is pressed while the energy-saving mode is canceled, the controller (C) executes the energy-saving mode, and when the selection button is pressed while the energy-saving mode is executed, the controller (C) cancels the energy-saving mode.

[0076] (5-2) Updating the Set Upper Limit Value When the energy saving mode is being executed, the controller (C) updates the set upper limit value in accordance with the overall load of the air conditioner (1) (hereinafter referred to as the air conditioning load) and the room temperature. Below, a case where the controller (C) updates the set upper limit value will be described. The air conditioning load is the total load of the air conditioning outdoor unit (10), the load of the humidity control unit (20), and the load of the air conditioning indoor unit (30). "Updating the set upper limit value" means changing the energy saving condition value to another value without resetting it.

[0077] When the air conditioning load becomes high, the controller (C) updates the set upper limit value to a second value higher than the first value, and controls the rotation speed of the compressor (12) so that the power consumption becomes equal to or less than the second value. The "when the air conditioning load becomes high" refers to the following: (a) during cooling operation, the indoor temperature is higher than the target temperature and the temperature difference is equal to or less than a second predetermined value (ΔT C2 (b) When another heat source occurs in the room (I) during cooling operation, such as when a gas stove is turned on. (c) When the room temperature is lower than the target temperature during heating operation and the temperature difference is equal to or greater than a second predetermined value (ΔT C2 ) or more, (d) when air is introduced into the room (I) from outside, for example, by opening a window, (e) when the operation mode is changed from cooling to dehumidifying / cooling, or (f) when the operation mode is changed from heating to heating / humidifying. The second predetermined value is, for example, 2.5°C. When the air conditioning load increases, the power consumption of the air conditioner (1) increases. Therefore, if the set upper limit value is left at the first value, the rotation speed of the compressor (12) needs to be lowered to maintain the power consumption at or below the first value. If the rotation speed of the compressor (12) is lowered, the air conditioning performance decreases, making it difficult for the room temperature to approach the target temperature. When the air conditioning load increases, the controller (C) updates the set upper limit value to the second value, thereby maintaining or increasing the rotation speed of the compressor (12), thereby enabling the air conditioning performance to be fully exhibited.

[0078] When the air conditioning load is low, the controller (C) updates the set upper limit value to a third value lower than the second value and controls the rotation speed of the compressor (12) so that the power consumption is equal to or less than the third value. Examples of "when the air conditioning load is low" include: (g) when another heat source is generated in the room (I), such as when a gas stove is ignited during heating operation; (h) when the operation mode is changed from dehumidifying / cooling operation to cooling operation; and (i) when the operation mode is changed from heating / humidifying operation to heating operation. When the air conditioning load is low, the compressor (12) can be operated at a sufficient rotation speed even if the compressor (12) is controlled to reduce the power consumption. By updating the set upper limit value to the third value when the air conditioning load is low, the controller (C) can enhance the energy-saving effect while fully demonstrating the air conditioning performance. Note that the third value may be higher or lower than the first value as long as it is lower than the second value. For example, when the set upper limit value is set to a first value and the air conditioning load is low, the controller (C) can set a value lower than the first value as the third value. When the set upper limit value is set to a second value and the air conditioning load is low, the controller (C) can set a value higher than the first value and lower than the second value as the third value.

[0079] The controller (C) detects (a) to (d) and (i) based on the detection result of the inside air temperature sensor (53) and changes the set upper limit value to the second value or the third value. The controller (C) sets the second value and the third value based on the reference capacity value when the first value was set. For example, the controller (C) calculates the second value by multiplying the reference capacity value by a coefficient that is larger than that used when calculating the first value, and calculates the third value by multiplying the reference capacity value by a coefficient that is smaller than that used when calculating the second value.

[0080] When the indoor temperature remains below the target temperature for a second predetermined time or more during cooling operation, or when the indoor temperature remains above the target temperature for a second predetermined time or more during heating operation, the controller (C) updates the set upper limit to a fourth value lower than the first value. The controller (C) controls the rotation speed of the compressor (12) so that the power consumption is equal to or less than the fourth value. The second predetermined time is, for example, 20 minutes. The controller (C) sets the fourth value based on the first value. The controller (C) calculates the fourth value by multiplying the first value by a coefficient less than 1 (for example, 0.8). When the indoor temperature remains below the target temperature for a long period of time despite the setting of the set upper limit and the reduction in the rotation speed of the compressor (12), it is highly likely that the compressor (12) is performing at a higher capacity than necessary. In such a situation, the controller (C) further lowers the set upper limit to prevent the compressor (12) from operating excessively, thereby enhancing energy saving effects.

[0081] The controller (C) may change the first value according to a user setting. For example, the controller (C) may allow the user to select between "high energy saving" and "low energy saving," and when "high energy saving" is selected, the controller (C) may set the first value to a value smaller than when "low energy saving" is selected. For example, when "high energy saving" is selected by the user, the controller (C) may set the coefficient by which the reference capacity value is multiplied to 0.8, and when "low energy saving" is selected by the user, the controller (C) may set the coefficient by which the reference capacity value is multiplied to 0.9.

[0082] (5-3) Resetting of the set upper limit value When the controller (C) is performing cooling operation or heating operation in energy saving mode, the controller (C) may reset the reference capacity value and the set upper limit value and reset the first value as the reference capacity value and the set upper limit value. The controller (C) resets the reference capacity value and the first value when any of the following three conditions is met: - The thermo-off condition is satisfied - The target temperature is reset to a lower temperature during cooling operation - The target temperature is reset to a higher temperature during heating operation

[0083] (5-3-1) Thermo-off Thermo-off is a control in which the controller (C) stops the air conditioning operation of the air conditioner (1) when the condition (hereinafter referred to as the thermo-off condition) is met that the temperature in the air-conditioned space is outside a predetermined allowable temperature range including the set temperature of the air conditioner (1). Specifically, in the case of cooling operation, when the indoor temperature is below the thermo-off temperature (ΔT OFF ) or more, in the case of heating operation, the indoor temperature is the thermo-off temperature (ΔT OFF ), the controller (C) stops the air conditioning operation of the air conditioner (1). That is, the controller (C) stops the compressor (12) when a predetermined thermo-off condition is satisfied. When the state where the thermo-off condition is satisfied changes to a state where the thermo-off condition is not satisfied, the controller (C) operates the compressor (12) again. The state where the thermo-off condition is not satisfied is a state where the indoor temperature rises or falls and the difference between the indoor temperature and the target temperature becomes less than the thermo-off temperature.

[0084] The controller (C) resets the reference capacity value and the first value when a predetermined thermo-off condition is satisfied. When the controller (C) changes from a state in which the thermo-off condition is satisfied to a state in which the thermo-off condition is not satisfied, the controller (C) resets the reference capacity value and the first value based on the power consumption after a third predetermined time has elapsed since the thermo-off condition was no longer satisfied. The controller (C) sets the reset first value as the set upper limit value. The controller (C) controls the rotation speed of the compressor (12) so that the power consumption is equal to or less than the reset first value. The third predetermined time is, for example, five minutes. When the compressor (12) is restarted, power consumption temporarily increases. Therefore, if the power consumption at the moment the compressor (12) is started is used as the reference capacity value, the set upper limit value may be set higher than necessary. After the compressor (12) restarts, the controller (C) waits for the operation of the compressor (12) to stabilize before resetting the reference capacity value and the first value.

[0085] (5-3-2) Changing the Target Temperature When the target temperature is reset to a lower temperature during cooling operation, the controller (C) resets the reference capacity value and the first value. When the target temperature is reset to a lower temperature during cooling operation, it is necessary to increase the rotation speed of the compressor (12) so that the room temperature approaches the target temperature quickly. Because it is difficult to increase the rotation speed of the compressor (12) when the first value is set, the controller (C) resets the reference capacity value and the first value.

[0086] The controller (C) determines whether the difference (ΔT) between the room temperature and the reset target temperature is equal to or greater than a first predetermined value (ΔT C1 ) When the following state continues for a first predetermined time, the power consumption at the time when the first predetermined time has elapsed is reset as a new reference capacity value. The controller (C) resets a first value lower than the reset reference capacity value as the set upper limit value. The controller (C) controls the rotation speed of the compressor (12) so that the power consumption becomes equal to or less than the new first value.

[0087] The controller (C) resets the reference capacity value and the first value when the target temperature is reset to a higher temperature during heating operation, as in cooling operation. The controller (C) resets the reference capacity value and the first value when the difference (ΔT) between the room temperature and the reset target temperature is equal to or exceeds a first predetermined value (ΔT C1 ) When the state below continues for a first predetermined time, the reference capacity value and the first value are reset, as in the cooling operation, and the rotation speed of the compressor (12) is controlled so that the power consumption becomes equal to or less than the new first value.

[0088] (5-4) Interruption of Energy-Saving Mode The controller (C) may interrupt the energy-saving mode when the cooling operation or heating operation is being performed in the energy-saving mode. The controller (C) may interrupt the energy-saving mode when: - During cooling operation, the room temperature is higher than the target temperature and the temperature difference is equal to or smaller than the third predetermined value (ΔT C3 During heating operation, the room temperature is lower than the target temperature and the temperature difference is equal to or greater than the third predetermined value (ΔT C3 ) or more. During cooling operation, the room temperature exceeds the first predetermined temperature (T MAX ) or more. During heating operation, the room temperature exceeds the second predetermined temperature (T MIN ) or less, the energy saving mode is interrupted when any of the following four conditions is met:

[0089] When the energy saving mode is interrupted, the controller (C) controls the rotation speed of the compressor (12) so that the room temperature approaches the target temperature. The controller (C) controls the rotation speed of the compressor (12) so that the room temperature approaches the target temperature when the difference (ΔT) between the room temperature and the target temperature reaches a first predetermined value (ΔT C1 The controller (C) restarts the energy saving mode when the difference (ΔT) between the room temperature and the target temperature becomes equal to or less than a first predetermined value (ΔT C1 ) The power consumption at the time when the following state has continued for a first predetermined time is reset as the reference capacity value. The controller (C) resets a first value lower than the reference capacity value as the set upper limit value. The controller (C) controls the rotation speed of the compressor (12) so that the power consumption is equal to or less than the reset first value.

[0090] (5-5) Flowchart during Cooling Operation FIGS. 8 to 10 are examples of flowcharts showing the processing operations of the controller (C) when performing cooling operation in the energy saving mode.

[0091] As shown in Fig. 8, when the energy saving mode is started in step S102 during the cooling operation in step S101, the process proceeds to step S103. In step S103, the controller compares the indoor temperature (T) with the target temperature (T a ) is less than or equal to a first predetermined value (ΔT C1 ) has continued for a first predetermined time.

[0092] In step S103, the indoor temperature (T) and the target temperature (T a ) is less than or equal to a first predetermined value (ΔT C1 ) has continued for a first predetermined time, the process proceeds to step S104 and step S105, where a reference capacity value and a first value based on the reference capacity value are set. Once the first value has been set, the process proceeds to step S106. In step S106, the first value is set as a set upper limit value, and the rotation speed (operating frequency) of the compressor (12) is controlled so that the power consumption of the air conditioner (1) is smaller than the first value.

[0093] In the next step S107, it is determined whether or not there is a command to turn off the energy-saving mode. The command to turn off the energy-saving mode is transmitted to the controller (C) when a user presses a button on the remote controller (40) to turn off the energy-saving mode or when a user presses a button on the remote controller (40) to turn off the operation of the air conditioner (1) itself. When the command to turn off the energy-saving mode is input to the controller (C), the energy-saving mode ends in step S108.

[0094] If there is no command to turn off the energy saving mode in step S107, the process proceeds to steps S109 and S110. In steps S109 and S110, it is determined whether or not the conditions for suspending the energy saving mode are met. In step S109, the indoor temperature (T) is set to a target temperature (T a ) to the third predetermined value (ΔT C3 In step S110, it is determined whether the indoor temperature (T) is equal to or greater than the value obtained by adding the first predetermined temperature (T MAX ) or more.

[0095] The indoor temperature (T) is equal to the target temperature (T a ) to the third predetermined value (ΔT C3 ) or more, or the first predetermined temperature (T MAX ), the energy saving mode is interrupted in step S111. After the energy saving mode is interrupted, the indoor temperature (T) and the target temperature (T a ) is less than or equal to a first predetermined value (ΔT C1 If the condition (1) is satisfied, the process proceeds to step S113, where the energy saving mode is resumed. After the energy saving mode is resumed, the process returns to step S103.

[0096] If the conditions for suspending the energy saving mode are not met, it is determined in steps S114, S117, and S120 whether the conditions for updating the set upper limit value are met. In step S114, it is determined whether the air conditioning load is increasing. If the air conditioning load is increasing, the process proceeds to steps S115 and S116 in this order. In this case, a second value higher than the first value is set based on the reference capacity value. The controller (C) updates the set upper limit value to the second value and controls the rotation speed of the compressor (12) so that the power consumption of the air conditioner (1) is equal to or less than the second value. In step S117, it is determined whether the air conditioning load is decreasing. If the air conditioning load is decreasing, the process proceeds to steps S118 and S119 in this order. In this case, a third value lower than the second value is set based on the reference capacity value. The controller (C) updates the set upper limit value to a third value and controls the rotation speed of the compressor (12) so that the power consumption of the air conditioner (1) becomes equal to or less than the third value.

[0097] When the air conditioning load does not change and the process proceeds to step S120, the indoor temperature (T) is equal to the target temperature (T a ) to the thermo-off temperature (ΔT OFF ) lower than the target temperature (T a ) has continued for a second predetermined time. If these conditions are met, the process proceeds to step S121 and then step S122. In this case, a fourth value lower than the first value is set based on the first value. The controller (C) updates the set upper limit value to the fourth value, and controls the rotation speed of the compressor (12) so that the power consumption of the air conditioner (1) is equal to or less than the fourth value. After step S122, the process returns to step S107.

[0098] If the conditions for updating the set upper limit value are not met, it is determined in steps S123 and S129 whether the conditions for resetting the reference capacity value and the set upper limit value are met. In step S123, it is determined whether the thermo-off condition is met, i.e., whether the indoor temperature (T) is equal to or lower than the target temperature (T a ) to the thermo-off temperature (ΔT OFFIf the thermo-off condition is satisfied, the controller (C) stops the operation of the compressor (12) in step S124, and resets the reference capacity value and the set upper limit value in step S125. After resetting the reference capacity value and the set upper limit value, the process proceeds to step S126, where it is determined whether the thermo-off condition is no longer satisfied, i.e., whether the room temperature (T) is lower than the target temperature (T a ) to the thermo-off temperature (ΔT OFF ) is subtracted from the calculated value. If the thermo-off condition is no longer satisfied, the controller (C) operates the compressor (12) again in step S127. When the third predetermined time has elapsed after the compressor (12) has been operated, the process returns to step S104.

[0099] If the thermo-off condition is not met and the process proceeds to step S129, the target temperature (T a It is determined whether the target temperature (T a When the target temperature (T) is changed, the controller (C) resets the reference capacity value and the set upper limit value in step S130. After resetting the reference capacity value and the set upper limit value, the process returns to step S103. a If the value of the parameter 100 is not changed, the process returns to step S107.

[0100] The flowchart shown here is an example, and the order of the steps of turning off the energy saving mode (steps S107 and S108), suspending the energy saving mode (steps S109 to S113), updating the set upper limit value (steps S114 to S122), and resetting the set upper limit value (steps S123 to S130) after controlling the rotation speed of the compressor (12) in step S106 is not particularly limited. Furthermore, the controller (C) may process these steps simultaneously.

[0101] (5-6) Flowchart during heating operation FIGS. 11 to 13 are examples of flowcharts showing the processing operations of the controller (C) when performing heating operation in the energy saving mode.

[0102] As shown in Fig. 8, when the energy saving mode is started in step S202 during the cooling operation in step S201, the process proceeds to step S203. In step S203, the controller calculates the indoor temperature (T) and the target temperature (T a ) is less than or equal to a first predetermined value (ΔT C1 ) has continued for a first predetermined time.

[0103] In step S203, the indoor temperature (T) and the target temperature (T a ) is less than or equal to a first predetermined value (ΔT C1 ) has continued for a first predetermined time, the process proceeds to step S204 and step S205, where a reference capacity value and a first value based on the reference capacity value are set. Once the first value has been set, the process proceeds to step S206. In step S206, the first value is set as a set upper limit value, and the rotation speed of the compressor (12) is controlled so that the power consumption of the air conditioner (1) is smaller than the first value.

[0104] In the next step S207, it is determined whether or not there is a command to turn off the energy saving mode. If a command to turn off the energy saving mode is input to the controller (C), the energy saving mode is ended in step S208.

[0105] If there is no command to turn off the energy saving mode in step S207, the process proceeds to steps S209 and S210. In steps S209 and S210, it is determined whether or not the conditions for suspending the energy saving mode are met. In step S209, the indoor temperature (T) is set to a target temperature (T a ) to the third predetermined value (ΔT C3 In step S210, it is determined whether the room temperature (T) is equal to or lower than the value obtained by subtracting the second predetermined temperature (T MIN ) or less.

[0106] The indoor temperature (T) is equal to the target temperature (T a ) to the third predetermined value (ΔT C3 ) minus the second predetermined temperature (T MIN), the energy saving mode is interrupted in step S211. After the energy saving mode is interrupted, the indoor temperature (T) and the target temperature (T a ) is less than or equal to a first predetermined value (ΔT C1 If the condition (1) is satisfied, the process proceeds to step S213, where the energy saving mode is resumed. After the energy saving mode is resumed, the process returns to step S203.

[0107] If the conditions for suspending the energy saving mode are not met, it is determined in steps S214, S217, and S220 whether the upper limit for updating the set upper limit value is met. In step S214, it is determined whether the air conditioning load is increasing. If the air conditioning load is increasing, the process proceeds to steps S215 and S216 in this order. In this case, a second value higher than the first value is set based on the reference capacity value. The controller (C) updates the set upper limit value to the second value and controls the rotation speed of the compressor (12) so that the power consumption of the air conditioner (1) is equal to or less than the second value. In step S217, it is determined whether the air conditioning load is decreasing. If the air conditioning load is decreasing, the process proceeds to steps S218 and S219 in this order. In this case, a third value lower than the second value is set based on the reference capacity value. The controller (C) updates the set upper limit value to a third value and controls the rotation speed of the compressor (12) so that the power consumption of the air conditioner (1) becomes equal to or less than the third value.

[0108] When the air conditioning load does not change and the process proceeds to step S220, the indoor temperature (T) is equal to the target temperature (T a ) to the thermo-off temperature (ΔT OFF ) higher than the target temperature (T a) has continued for a second predetermined time. If these conditions are met, the process proceeds to step S221 and step S222 in this order. In this case, a fourth value lower than the first value is set based on the first value. The controller (C) updates the set upper limit value to the fourth value, and controls the rotation speed of the compressor (12) so that the power consumption of the air conditioner (1) is equal to or less than the fourth value. After step S222, the process returns to step S207.

[0109] If the conditions for updating the set upper limit are not met, it is determined in steps S223 and S229 whether the conditions for resetting the reference capacity value and the set upper limit are met. In step S123, it is determined whether the thermo-off condition is met, i.e., whether the indoor temperature (T) is equal to or lower than the target temperature (T a ) to the thermo-off temperature (ΔT OFF ) is equal to or greater than the sum of the temperature (T) and the target temperature (T). If the thermo-off condition is satisfied, the controller (C) stops the operation of the compressor (12) in step S224, and resets the reference capacity value and the set upper limit value in step S225. After resetting the reference capacity value and the set upper limit value, the process proceeds to step S226, where it is determined whether the thermo-off condition is no longer satisfied, i.e., whether the room temperature (T) is equal to or greater than the target temperature (T a ) to the thermo-off temperature (ΔT OFF ) is added to the temperature. If the thermo-off condition is no longer satisfied, the controller (C) operates the compressor (12) again in step S227. When the third predetermined time has elapsed after the compressor (12) has been operated, the process returns to step S204.

[0110] If the thermo-off condition is not met and the process proceeds to step S229, the target temperature (T a It is determined whether the target temperature (T a When the target temperature (T) is changed, the controller (C) resets the reference capacity value and the set upper limit value in step S230. After resetting the reference capacity value and the set upper limit value, the process returns to step S203. aIf the value of the parameter 100 is not changed, the process returns to step S207.

[0111] The flowchart shown here is an example, and the order of the steps of turning off the energy saving mode (steps S207 and S208), suspending the energy saving mode (steps S209 to S213), updating the set upper limit value (steps S214 to S222), and resetting the set upper limit value (steps S223 to S230) after controlling the rotation speed of the compressor (12) in step S206 is not particularly limited. Furthermore, the controller (C) may process these steps simultaneously.

[0112] (5-7) Time Charts FIGS. 12 and 13 are examples of time charts when cooling operation is performed in the energy saving mode.

[0113] In the example shown in Fig. 12, after the air conditioner (1) starts operating, at time t1, the difference between the room temperature and the target temperature becomes equal to or less than a first predetermined value, and continues to be equal to or less than a first predetermined time, that is, until time t2. The controller (C) sets the power consumption at time t2 as a reference capacity value, and sets a first value that is lower than the reference capacity value. The controller (C) controls the rotation speed of the compressor (12) so that the power consumption becomes equal to or less than the first value.

[0114] After time t2, the indoor temperature rises, and at time t3, when the indoor temperature is higher than the target temperature by at least a second predetermined value, the air conditioning load increases, and therefore the controller (C) calculates a second value based on the reference capacity value. The controller (C) controls the rotation speed of the compressor (12) so that the power consumption is equal to or less than the second value. If the indoor temperature continues to rise and the air conditioning load increases even after the set upper limit value has been updated to the second value, the controller (C) updates the second value to a larger value at time t4. The controller (C) controls the rotation speed of the compressor (12) so that the power consumption is equal to or less than the updated second value.

[0115] If the room temperature continues to rise after time t4 and becomes higher than the target temperature by at least a third predetermined value at time t5, the controller (C) suspends the energy saving mode and increases the rotation speed of the compressor (12).

[0116] When the difference between the room temperature and the target temperature becomes equal to or less than a first predetermined value at time t6 after the energy-saving mode is interrupted, the energy-saving mode is resumed. At time t7, when the state in which the difference between the room temperature and the target temperature remains equal to or less than the first predetermined value for a first predetermined time, the controller (C) sets the power consumption at time t7 as a new reference capacity value. The controller (C) sets a new first value based on the new reference capacity value and controls the rotation speed of the compressor (12) so that the power consumption becomes equal to or less than the first value.

[0117] If the indoor temperature rises and becomes higher than the target temperature by at least a second predetermined value, and the set upper limit value is updated to the second value, and then the indoor temperature falls without becoming higher than the target temperature by at least a third predetermined value, the controller (C) calculates a third value based on the reference capacity value. The controller (C) updates the set upper limit value to the third value and controls the rotation speed of the compressor (12) so that the power consumption is equal to or less than the updated third value.

[0118] In the example shown in Fig. 13, after the air conditioner (1) starts operating, at time tA, the difference between the room temperature and the target temperature becomes equal to or less than a first predetermined value, and continues to be equal to or less than a first predetermined time, that is, until time tB, which is the first predetermined time later. The controller (C) sets the power consumption at time t2 as a reference capacity value, and sets a first value that is lower than the reference capacity value. The controller (C) controls the rotation speed of the compressor (12) so that the power consumption becomes equal to or less than the first value.

[0119] If the indoor temperature continues to decrease after time tB and, at time tC, the indoor temperature remains between the target temperature and a temperature lower than the target temperature by the thermo-off temperature for a second predetermined time, the controller (C) sets a fourth value lower than the first value based on the first value. The controller (C) controls the rotation speed of the compressor (12) so that the power consumption is equal to or less than the fourth value.

[0120] After time tC, at time tD, the indoor temperature is the thermo-off temperature (ΔT OFF ), the controller (C) stops the compressor (12) and resets the reference capacity value and the set upper limit value (here, the fourth value).

[0121] At time tE, the difference between the indoor temperature and the target temperature becomes the thermo-off temperature (ΔTOFF ), the controller (C) operates the compressor (12) again. The controller (C) sets the power consumption at time tF, when a third predetermined time has elapsed since the compressor (12) was operated, as the reference capacity value again. The controller (C) sets a new first value based on the new reference capacity value, and controls the rotation speed of the compressor (12) so that the power consumption becomes equal to or less than the first value.

[0122] After time tF, at time tG, when the target temperature is set to a lower temperature, the controller (C) resets the reference capacity value and the set upper limit value (here, the first value). After the reset, at time tH, when the difference between the room temperature and the target temperature becomes equal to or less than the first predetermined value and continues until time tI, which is the first predetermined time later, the controller (C) resets the power consumption at time tI as the reference capacity value. The controller (C) sets a new first value based on the reference capacity value and controls the rotation speed of the compressor (12) so that the power consumption becomes equal to or less than the first value.

[0123] (6) Modifications The above embodiment may be modified as follows.

[0124] The controller (C) determines whether the difference between the room temperature and the target temperature is equal to or greater than a first predetermined value (ΔT C1 The condition that a certain time has elapsed since the start of the cooling operation or the heating operation may be adopted as the condition that the reference capacity value and the first value become equal to or less than the first predetermined time. In this case, the controller (C) may set the reference capacity value and the first value when the certain time has elapsed, without waiting for the first predetermined time to elapse.

[0125] The air conditioning capacity value may be the load of the air conditioning outdoor unit (10) instead of the total power consumption of the air conditioner (1). In this case, the controller (C) determines whether the difference between the indoor temperature and the target temperature is equal to or exceeds a first predetermined value (ΔT C1 ) is set as a reference capacity value. The controller (C) controls the rotation speed of the compressor (12) so that the load of the air conditioning outdoor unit (10) is equal to or less than a first value set based on the reference capacity value. If the load of the air conditioning outdoor unit (10) is reduced, the overall power consumption of the air conditioner (1) is reduced, and therefore, a sufficient energy-saving effect can be obtained.

[0126] When calculating the first value, the controller (C) may calculate the first value by subtracting a certain number from the reference ability value.

[0127] The controller (C) may store in advance a table for setting the first value according to the reference capability value, and may set the first value by reading the table. In this case, the controller (C) may also set the second value, the third value, and the fourth value based on the pre-stored table.

[0128] (7) Other Embodiments Although the embodiments and modifications have been described above, it will be understood that various modifications in form and details are possible without departing from the spirit and scope of the claims. Furthermore, the above embodiments, modifications, and other embodiments may be combined or substituted as appropriate as long as the functionality of the subject matter of the present disclosure is not impaired.

[0129] The air conditioner (1) may be an air conditioner capable of only one of cooling operation and heating operation.

[0130] The air conditioning unit (5) has a heat pump type refrigerant circuit, but may be any type capable of heating air. For example, the air conditioning unit (5) may heat air using a heater or a radiant panel.

[0131] The above-mentioned descriptions such as "first," "second," "third," etc. are used to distinguish the words to which these descriptions are attached, and do not limit the number or order of the words.

[0132] INDUSTRIAL APPLICABILITY As described above, the present disclosure is useful for air conditioning apparatuses.

[0133] 1 Air conditioning unit 12 Compressor C Controller

Claims

1. An air conditioning apparatus capable of at least one of cooling operation and heating operation, comprising: a compressor (12); and a controller (C) that controls the compressor (12), wherein the controller (C) is capable of executing a first mode in which the rotation speed of the compressor (12) is controlled so that an air conditioning capacity value is equal to or lower than an upper limit value, and wherein the first mode is a mode in which the air conditioning capacity value in a state in which a condition is met in which a difference between an indoor temperature and a target temperature is equal to or lower than a first predetermined value is set as a reference capacity value, and a first value lower than the reference capacity value is set as the upper limit value.

2. An air conditioning apparatus according to claim 1, wherein the first value is a variable value that fluctuates based on the reference capacity value.

3. An air-conditioning apparatus according to claim 2, wherein the first value is higher when the air-conditioning load is high than when the air-conditioning load is low.

4. An air-conditioning apparatus according to claim 3, wherein the controller (C) changes the upper limit value to a second value higher than the first value when the air-conditioning load becomes high, thereby controlling the rotation speed of the compressor (12).

5. An air-conditioning apparatus according to claim 4, wherein the controller (C) changes the upper limit value to a third value lower than the second value when the air-conditioning load becomes low, thereby controlling the rotation speed of the compressor (12).

6. An air-conditioning apparatus according to claim 1, wherein the controller (C) changes the upper limit value to a fourth value lower than the first value and controls the rotation speed of the compressor (12) when the indoor temperature remains below the target temperature for a predetermined period of time or more during the cooling operation, or when the indoor temperature remains above the target temperature for a predetermined period of time or more during the heating operation.

7. An air conditioning apparatus according to claim 1, wherein the first value is a value that varies according to a user setting.

8. An air-conditioning apparatus according to any one of claims 1 to 7, wherein the controller (C) stops the compressor (12) and resets the reference capacity value and the upper limit value when a predetermined thermo-off condition is satisfied, and operates the compressor (12) when the state changes from one in which the thermo-off condition is satisfied to one in which the thermo-off condition is no longer satisfied, and resets the reference capacity value and the first value based on the air-conditioning capacity value after the state in which the thermo-off condition is no longer satisfied, and controls the rotation speed of the compressor (12) with the reset first value as the upper limit value.

9. An air-conditioning apparatus according to any one of claims 1 to 8, wherein the controller (C) resets the standard capacity value and the upper limit value when the target temperature is changed to a lower temperature during the cooling operation, or when the target temperature is changed to a higher temperature during the heating operation, and resets the standard capacity value and the first value based on the air-conditioning capacity value in a state where a condition is established in which the difference between the indoor temperature and the changed target temperature is equal to or less than a predetermined value, and controls the rotation speed of the compressor (12) using the reset first value as the upper limit value.

10. An air-conditioning apparatus according to any one of claims 1 to 9, wherein the controller (C) interrupts the first mode when, during execution of the first mode, the indoor temperature becomes higher than the target temperature by a second predetermined value greater than the first predetermined value during cooling operation, or when, during heating operation, the indoor temperature becomes lower than the target temperature by the second predetermined value or more.

11. An air-conditioning apparatus according to any one of claims 1 to 10, wherein the controller (C) interrupts the first mode when, during execution of the first mode, the indoor temperature during cooling operation becomes equal to or higher than a first predetermined temperature, or when, during heating operation, the indoor temperature becomes equal to or lower than a second target temperature which is lower than the first predetermined temperature.

12. An air-conditioning apparatus according to any one of claims 1 to 11, wherein the air-conditioning capacity value is the amount of power consumed by the air-conditioning apparatus.

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