JP7625145B2 - Air conditioner and air conditioning system - Google Patents

Description

The present disclosure relates to air conditioning devices and air conditioning systems.

Conventionally, air conditioners are known that perform control (hereinafter also referred to as energy saving control) to improve operating efficiency by changing the target evaporation temperature for evaporating the refrigerant in the evaporator according to the air conditioning load. Air conditioners that perform energy saving control are expected to have a greater energy saving effect in buildings with low air conditioning loads or in intermediate seasons (spring and fall) when the heat generation load is low, because they can control the refrigerant temperature to the target evaporation temperature with small temperature changes. In such air conditioners, the indoor temperature is brought close to the set temperature set by the user in a short period of time, mainly from the perspective of ensuring comfort, so that the specifications are such that energy saving control is not entered for a certain period of time after the compressor is started (thermo on).

The air conditioner in Patent Document 1 (JP Patent Publication 2002-147823 A) determines the control characteristics of the target value of the evaporation temperature in response to the cooling load characteristics of the building. The air conditioner in Patent Document 1 is configured to change the target value of the evaporation temperature based on the temperature difference between the indoor set temperature and the outdoor air temperature in accordance with this control characteristic.

The air conditioner in Patent Document 2 (JP Patent Publication 2015-021656 A) predicts the generated heat load from the temperature difference between the indoor set temperature and the actual intake temperature, turns on the thermo function, and continues operation for a certain period of time. After that, if the temperature difference is greater than the set value, the air conditioner in Patent Document 2 executes control to set the compressor rotation speed to the minimum value.

JP 2002-147823 A JP 2015-021656 A

When selecting an air conditioning unit model, there is a tendency to select an air conditioning unit with a capacity that is somewhat excessive relative to the air conditioning load. For this reason, for example, in air conditioning units that have a capacity that is somewhat excessive relative to the air conditioning load even in the summer when the air conditioning load is high, the load rate relative to the air conditioning capacity (hereinafter also referred to as the air conditioning load rate) is low. When attempting to perform energy saving control using an air conditioning unit with a low air conditioning load rate, the issue is that the expected energy saving effect cannot be obtained due to the repeated starting (thermo on) and stopping (thermo off) of the compressor.

The air conditioning device described in Patent Document 1 is capable of suppressing excess air conditioning capacity when an inside/outside temperature difference, which is the difference between the indoor set temperature and the outside air temperature, always occurs. However, the air conditioning device described in Patent Document 1 does not take into consideration reducing the frequency of compressor start-up and stoppage when the air conditioning load rate is low.

The air conditioning device described in Patent Document 2 predicts the heat load generated from the temperature difference between the set temperature and the suction temperature, and is able to reduce the frequency of the compressor starting and stopping repeatedly. However, the air conditioning device described in Patent Document 2 does not anticipate cases where the air conditioning load rate is low, in which a temperature difference between the set temperature and the suction temperature is unlikely to occur, and in such cases the energy saving effect is limited.

The objective of the present invention is to provide an air conditioning device and an air conditioning system that can achieve energy saving effects even when using an air conditioning device with a low air conditioning load rate.

The air conditioner according to the present disclosure is an air conditioner including a refrigerant circuit including an outdoor unit and an indoor unit. The indoor unit includes an indoor heat exchanger through which a refrigerant flows. The outdoor unit includes a compressor. The air conditioner includes a detection device that detects data during operation of the refrigerant circuit, and a control device that controls the refrigerant circuit. The control device calculates the air conditioning capacity exhibited by the air conditioner from the data detected by the detection device, and controls the compressor to operate in a first mode when a ratio of the calculated air conditioning capacity to the rated capacity of the air conditioner is greater than a preset threshold, and controls the compressor to operate in a second mode when the ratio is equal to or less than the preset threshold. The first mode is a control that changes a target value of the temperature of the refrigerant flowing through the indoor heat exchanger from a first temperature to a second temperature different from the first temperature after a certain grace period has elapsed since the compressor started operating. The second mode is a control that changes a target value of the temperature of the refrigerant flowing through the indoor heat exchanger from a first temperature to a second temperature without a grace period from the start of operation of the compressor, or by providing a grace period shorter than the first mode.

The air conditioning system according to the present disclosure includes an air conditioning apparatus having a refrigerant circuit including an outdoor unit and an indoor unit, and a server device connected to the air conditioning apparatus via a network. The indoor unit includes an indoor heat exchanger through which a refrigerant flows. The outdoor unit includes a compressor. The air conditioning apparatus includes a detection device that detects data during operation of the refrigerant circuit, and a control device that transmits detection data of the detection device to the server device and controls the refrigerant circuit based on control data received from the server device. The server device calculates the air conditioning processing capacity exhibited by the air conditioning apparatus based on the detection data from the detection device, and creates first control data to operate the compressor in a first mode when the ratio of the calculated air conditioning processing capacity to the rated capacity of the air conditioning apparatus is greater than a preset threshold, and creates second control data to operate the compressor in a second mode when the ratio is equal to or less than the preset threshold. The first control data is data for changing a target value of the temperature of the refrigerant flowing through the indoor heat exchanger from a first temperature to a second temperature different from the first temperature after a certain grace period has elapsed since the compressor started operating. The second control data is data for changing the target value of the temperature of the refrigerant flowing through the indoor heat exchanger from the first temperature to the second temperature without setting a grace period from the start of compressor operation or by setting a grace period shorter than that in the first mode.

According to the air conditioning device and air conditioning system disclosed herein, the compressor is operated in the first mode or the second mode depending on whether the ratio of the calculated air conditioning processing capacity to the rated capacity of the air conditioning device is below a preset threshold value, so that energy saving effects can be obtained even when using an air conditioning device with a low air conditioning load rate.

1 is a schematic diagram showing the configuration of an air conditioning apparatus in a first embodiment. 1 is a diagram showing a refrigerant circuit of an air-conditioning apparatus according to a first embodiment. 11 is a graph showing the relationship between the difference between the suction temperature and the set temperature in the indoor unit and the target evaporation temperature. 1 is a graph showing the relationship between time and a target evaporation temperature. 5 is a flowchart showing control during a cooling operation in the first embodiment. 10 is a flowchart showing control during a heating operation in the second embodiment. FIG. 11 is a schematic diagram showing the configuration of an air conditioning system in embodiment 3.

The following describes in detail the embodiments of the present disclosure with reference to the drawings. In the embodiments described below, when numbers, quantities, etc. are mentioned, the scope of the present disclosure is not necessarily limited to those numbers, quantities, etc., unless otherwise specified. The same reference numbers are used for the same parts and corresponding parts, and duplicate descriptions may not be repeated. It is intended from the beginning that the configurations in the embodiments will be used in appropriate combinations.

Embodiment 1.
FIG. 1 is a schematic diagram showing the configuration of an air conditioner 1 in embodiment 1. The air conditioner 1 includes an indoor unit 200, an outdoor unit 12, and a control device 20. The indoor unit 200 includes a plurality of indoor units 11. The air conditioner 1 may be configured to include one outdoor unit 12 and one indoor unit 11, or may be configured to include a plurality of outdoor units. The outdoor unit 12 and the indoor unit 11 are connected by piping. The inside of the piping is configured so that a refrigerant circulates.

The outdoor unit 12 is installed outside the space to be air-conditioned. The indoor unit 11 is installed within the space to be air-conditioned. The space to be air-conditioned is, for example, the interior of a building. The refrigerant is, for example, an HFC refrigerant such as R32, an HCFC refrigerant such as R22, or a natural refrigerant such as R410A, _CO2 , or R290. The refrigerant may be a refrigerant other than the refrigerants shown here.

The control device 20 is composed of a CPU (Central Processing Unit) 21, memory 22 (ROM (Read Only Memory) and RAM (Random Access Memory)), and input/output devices (not shown) for inputting and outputting various signals. The CPU 21 deploys a program stored in the ROM into the RAM, etc. and executes it. The program stored in the ROM is a program in which the processing procedures of the control device 20 are written. The control device 20 controls each device in the indoor unit 11 and the outdoor unit 12 in accordance with these programs. This control is not limited to processing by software, and can also be processed by dedicated hardware (electronic circuits). The control device 20 may be provided on the indoor unit 200 side, or may be provided in a device separate from the outdoor unit 12 and the indoor unit 200.

Figure 2 is a diagram showing the refrigerant circuit 10 of the air conditioning apparatus 1 in embodiment 1. The refrigerant circuit 10 includes a plurality of indoor units 11 and an outdoor unit 12. The outdoor unit 12 includes a compressor 2, a four-way valve 3, an outdoor heat exchanger 4, and a fan 7. The indoor unit 11 includes an expansion valve 5, an indoor heat exchanger 6, and a fan 8.

The compressor 2 draws in, compresses, and discharges the refrigerant. The four-way valve 3 switches the refrigerant circulation direction between cooling and heating operations. In the refrigerant circuit 10 of Figure 2, the flow direction of the refrigerant during cooling operation is indicated by a solid arrow. During cooling operation, the indoor heat exchanger 6 functions as an evaporator, and the outdoor heat exchanger 4 functions as a condenser. During heating operation, the refrigerant flow direction is reversed. During heating operation, the indoor heat exchanger 6 functions as a condenser, and the outdoor heat exchanger 4 functions as an evaporator.

The outdoor heat exchanger 4 has multiple heat transfer tubes and exchanges heat between the outdoor air blown by the fan 7 and the refrigerant passing through the multiple heat transfer tubes. The expansion valve 5 expands the refrigerant and reduces its pressure. The expansion valve 5 is a device that can arbitrarily control the opening degree of, for example, an electronic expansion valve. The indoor heat exchanger 6 has multiple heat transfer tubes and exchanges heat between the indoor air blown by the fan 8 and the refrigerant passing through the multiple heat transfer tubes.

The air conditioning device 1 is equipped with multiple sensors as detection devices that detect data during operation of the refrigerant circuit 10. A pressure sensor 31a that detects the low pressure of the refrigerant circuit 10 is provided on the refrigerant suction side of the compressor 2. A pressure sensor 31b that detects the high pressure of the refrigerant circuit 10 is provided on the refrigerant discharge side of the compressor 2. Refrigerant temperature sensors 32a and 32b that detect the temperature of the refrigerant are provided on both ends of the outdoor heat exchanger 4. When the outdoor heat exchanger 4 functions as a condenser, the refrigerant temperature sensor 32a detects the refrigerant temperature on the inlet side of the outdoor heat exchanger 4, and the refrigerant temperature sensor 32b detects the refrigerant temperature on the outlet side of the outdoor heat exchanger 4. When the outdoor heat exchanger 4 functions as an evaporator, the refrigerant temperature sensor 32a detects the refrigerant temperature on the outlet side of the outdoor heat exchanger 4, and the refrigerant temperature sensor 32b detects the refrigerant temperature on the inlet side of the outdoor heat exchanger 4.

Refrigerant temperature sensors 33a and 33b are provided at both ends of the indoor heat exchanger 6 to detect the temperature of the refrigerant. When the indoor heat exchanger 6 functions as an evaporator, the refrigerant temperature sensor 33b detects the refrigerant temperature on the inlet side of the indoor heat exchanger 6, and the refrigerant temperature sensor 33a detects the refrigerant temperature on the outlet side of the indoor heat exchanger 6. When the indoor heat exchanger 6 functions as a condenser, the refrigerant temperature sensor 33b detects the refrigerant temperature on the outlet side of the indoor heat exchanger 6, and the refrigerant temperature sensor 33a detects the refrigerant temperature on the inlet side of the indoor heat exchanger 6. The refrigerant temperature sensors 32a, 32b, 33a, and 33b are connected to the control device 20 via signal lines not shown. The pressure sensors 31a and 31b are connected to the control device 20 via signal lines not shown.

Although not shown, the outdoor unit 12 is provided with an outdoor air temperature sensor that detects the outdoor air temperature, and the indoor unit 11 is provided with a room temperature sensor that detects the room temperature and a humidity sensor that detects the room humidity. The indoor unit 11 may also be provided with an air volume sensor that detects the air volume at the air outlet. These sensors may be connected to the control device 20 via signal lines (not shown). This allows data detected by each sensor to be transmitted to the control device 20.

The control device 20 performs arithmetic processing using the data transmitted from each sensor. The details of the arithmetic processing will be described later. The control device 20 controls the compressor 2, the fans 7 and 8, and the expansion valve 5 using control data created based on the arithmetic processing.

Next, the relationship between the difference between the suction temperature and the set temperature in the indoor unit 200 during cooling operation and the target evaporation temperature will be explained. Figure 3 is a graph showing the relationship between the difference between the suction temperature and the set temperature in the indoor unit 200 and the target evaporation temperature. The suction temperature is the indoor temperature detected by an indoor temperature sensor provided in the indoor unit 11. The set temperature is an arbitrary temperature set by the user via an input device such as a remote control. The target evaporation temperature is the target temperature for the refrigerant flowing through the indoor heat exchanger 6, which functions as an evaporator.

As shown in Figure 3, when the difference between the suction temperature and the set temperature in the indoor unit 200 is small, the target evaporation temperature is high. Conversely, when the difference between the suction temperature and the set temperature in the indoor unit 200 is large, the target evaporation temperature is low. In other words, the target evaporation temperature can be set higher when the difference between the suction temperature and the set temperature is small than when the difference between the suction temperature and the set temperature is large. Being able to set the target evaporation temperature high means that the compressor 2 can be controlled more gently. Therefore, when the target evaporation temperature is set high, a greater energy saving effect can be obtained than when the target evaporation temperature is set low.

Figure 4 is a graph showing the relationship between time and target evaporation temperature. Figure 4(a) shows the relationship between time and target evaporation temperature when compressor 2 is controlled in the first mode during normal operation. Figure 4(b) shows the relationship between time and target evaporation temperature when compressor 2 is controlled in the second mode during energy saving operation. Thermo on in the figure indicates that compressor 2 is starting up, and thermo off indicates that compressor 2 is stopping. The control device 20 executes control in the first mode or the second mode by controlling the rotation speed of compressor 2. Note that thermo on also controls the rotation speed when compressor 2 is started up, and can therefore also be said to be an operation of setting the rotation speed.

As shown in FIG. 4(a), the control device 20 maintains the temperature of the refrigerant in the indoor heat exchanger 6, which functions as an evaporator, at a target value a [°C] for a predetermined certain grace period β1 [min] after the first mode is turned on. The control device 20 controls the target value of the refrigerant temperature to be changed from a [°C] to b [°C] higher than a [°C] after the grace period β1 [min] has elapsed. β1 is, for example, 10 [min]. The temperature of the refrigerant in the indoor heat exchanger 6 is changed from a [°C] to b [°C]. The control device 20 turns off the compressor 2 after maintaining the target value of the refrigerant temperature at b [°C] for a certain period. Thereafter, the control device 20 repeats the control of changing the target evaporation temperature from a [°C] to b [°C], thereby repeatedly turning the compressor 2 on and off.

As shown in FIG. 4(b), in the second mode, the control device 20 controls the refrigerant temperature of the indoor heat exchanger 6 to change from the target value a [°C] to b [°C] higher than a [°C] without providing a grace period β1 [min] after the thermo-on. As a result, the refrigerant temperature of the indoor heat exchanger 6 is changed from a [°C] to b [°C]. The control device 20 turns off the compressor 2 after maintaining the target value of the refrigerant temperature at b [°C] for a certain period of time. In the second mode, the grace period β1 [min] is not provided, and the period during which the target value of the refrigerant temperature is b [°C] is longer than in the first mode. In other words, in the second mode, the period during which the target value of the refrigerant temperature is controlled at b [°C] is longer than in the first mode, and the number of thermo-on and thermo-off of the compressor 2 is reduced accordingly.

In Fig. 4, a [°C] is, for example, 0 [°C], and b [°C] is, for example, 9 [°C]. As shown in Fig. 3, when the target evaporation temperature is set high, a higher energy saving effect can be obtained than when the target evaporation temperature is set low. For this reason, the second mode, in which the period during which the target value of the refrigerant temperature is b [°C] is longer than the first mode, can be said to have a higher energy saving effect.

Here, the first mode of normal operation and the second mode of energy saving operation will be described in detail. In the first mode, the refrigerant temperature is set low immediately after the compressor 2 is turned on, so that the indoor temperature can be brought closer to the set temperature set by the user in a short period of time. In other words, the first mode is an operation in which the time for rapid cooling at a low temperature is extended, and then the temperature is gradually changed to the set temperature. Therefore, the first mode can reduce discomfort and improve comfort in a short period of time.

In the second mode, energy saving effects are achieved when an air conditioner 1 with a low air conditioning load rate is used. A low air conditioning load rate means that the indoor temperature can be effectively lowered even with low power consumption. In other words, by using an air conditioner 1 with a low air conditioning load rate, it is possible to process the indoor heat load gradually at a high target evaporation temperature, and the period controlled at a high target evaporation temperature can be extended. In other words, the second mode is an operation that eliminates the time for initial rapid cooling and cools the indoor temperature over a long period until it reaches the set temperature. As a result, in the second mode, the number of times the compressor 2 is turned on and off can be reduced compared to the first mode, and a high energy saving effect can be achieved when an air conditioner 1 with a low air conditioning load rate is used.

Next, the control contents executed by the control device 20 will be described. FIG. 5 is a flowchart showing the control during cooling operation in embodiment 1. The processing of the flowchart in FIG. 5 is repeatedly called and executed as a subroutine from the main routine in the control of the control device 20. In FIG. 5, the processing during cooling operation will be described.

First, in step S (hereinafter simply referred to as "S") 11, the control device 20 acquires operation data during cooling operation from multiple sensors that are detection devices. Next, the control device 20 calculates the air conditioning processing capacity (generated air conditioning load) (S12). Here, the air conditioning processing capacity is the processing capacity of the air conditioner 1, so it can also be said to be the generated air conditioning load in that the air conditioning load generated in the room is changed by exerting the processing capacity. The calculation of the air conditioning processing capacity is obtained, for example, by the method described in Patent No. 6739671. Specifically, the control device 20 obtains the refrigerant flow rate in the outdoor unit 12 from a data table showing the relationship between the rotation speed of the compressor 2, the high pressure detected by the pressure sensor 31b, and the low pressure detected by the pressure sensor 31a, and the refrigerant flow rate.

The control device 20 calculates the Cv value from the opening degree of the expansion valve 5 and the expansion valve characteristic data table. The Cv value is a unique coefficient that indicates the ease of flow of a fluid. The control device 20 calculates the refrigerant flow rate in the indoor unit 11 using the Cv value. Specifically, the control device 20 calculates the refrigerant flow rate of the target indoor unit 11 = refrigerant flow rate in the outdoor unit 12 x [Cv value of the target indoor unit 11 / total value of the Cv values of the indoor units 11] from the relational expression. Next, the control device 20 calculates the evaporator inlet specific enthalpy using the liquid refrigerant temperature at the refrigerant outlet of the outdoor unit 12 and the specific enthalpy data table at the evaporator inlet. The control device 20 calculates the evaporator outlet specific enthalpy using the liquid refrigerant temperature and gas refrigerant temperature of the indoor unit 11 and the evaporator outlet specific enthalpy data table. The control device 20 calculates the air conditioning capacity from the relational expression: air conditioning capacity [kW] = refrigerant flow rate of indoor unit 11 [kg/h]/3600 × [evaporator outlet specific enthalpy - evaporator inlet specific enthalpy] [kJ/kg]. The control device 20 adds up the air conditioning capacity of each indoor unit 11 to calculate the air conditioning capacity of the entire indoor unit 200.

Next, the control device 20 calculates the ratio of the air conditioning processing capacity to the rated capacity of the air conditioner 1 = [air conditioning processing capacity (air conditioning load) / rated capacity] (S13). Next, the control device 20 determines whether or not air conditioning processing capacity (air conditioning load) / rated capacity ≦ α1 (S14). α1 is an arbitrary setting value that can be set by the user to determine whether or not to perform energy saving control during cooling operation. If the control device 20 determines in S14 that air conditioning processing capacity (air conditioning load) / rated capacity > α1, it sets the compressor 2 to be controlled in the first mode, which is normal operation (S16), and returns the process from the subroutine to the main routine. The first mode is a mode in which a grace period β1 is set.

If the control device 20 determines in S14 that the air conditioning processing capacity (air conditioning load)/rated capacity is equal to or less than α1, it sets the compressor 2 to be controlled in the second mode, which is an energy-saving operation (S15), and returns the process from the subroutine to the main routine. The second mode is a mode in which the refrigerant temperature is changed without providing a grace period β1.

In the air conditioning device 1, for example, α1 is set within the range of 0.4≦α1≦0.7. When α1 is set in this way, the number of times that the compressor 2 turns on and off during the second mode is roughly halved compared to the first mode. This allows the air conditioning device 1 to extend the time it takes to reach the target evaporation temperature (for example, b [°C] in Figure 4), enabling energy-saving operation.

Embodiment 2.
Fig. 6 is a flowchart showing control during heating operation in embodiment 2. During heating operation, the indoor heat exchanger 6 functions as a condenser and the outdoor heat exchanger 4 functions as an evaporator by switching the four-way valve 3 shown in Fig. 2 to the dotted line side.

First, in step S21, the control device 20 acquires operation data during heating operation from a plurality of sensors that are detection devices. Next, the control device 20 calculates the air conditioning processing capacity (the generated air conditioning load) (S22). The air conditioning processing capacity is calculated, for example, by the method described in Patent No. 6739671. Specifically, the control device 20 calculates the refrigerant flow rate in the outdoor unit 12 from a data table showing the relationship between the rotation speed of the compressor 2, the high pressure detected by the pressure sensor 31b, the low pressure detected by the pressure sensor 31a, and the refrigerant flow rate.

The control device 20 obtains the Cv value from the opening degree of the expansion valve 5 and the expansion valve characteristic data table. The control device 20 obtains the refrigerant flow rate in the indoor unit 11 using the Cv value. Specifically, the control device 20 obtains the refrigerant flow rate of the target indoor unit 11 = refrigerant flow rate in the outdoor unit 12 x [Cv value of the target indoor unit 11 / total value of the Cv values of the indoor units 11] from the relational expression. Next, the control device 20 obtains the condenser inlet specific enthalpy using the gas refrigerant temperature at the refrigerant inlet of the indoor unit 11 and the condenser inlet specific enthalpy data table. The control device 20 obtains the condenser outlet specific enthalpy using the liquid refrigerant temperature of the indoor unit 11 and the condenser outlet specific enthalpy data table. The control device 20 obtains the air conditioning processing capacity from the relational expression: air conditioning processing capacity [kW] = refrigerant flow rate of the indoor unit 11 [kg/h]/3600 x [condenser outlet specific enthalpy - condenser inlet specific enthalpy] [kJ/kg]. The control device 20 adds up the air conditioning capacity of each indoor unit 11 to determine the air conditioning capacity of the entire indoor unit 200 .

Next, the control device 20 calculates the ratio of the air conditioning processing capacity to the rated capacity of the air conditioner 1 = [air conditioning processing capacity (air conditioning load) / rated capacity] (S23). Next, the control device 20 determines whether or not air conditioning processing capacity (air conditioning load) / rated capacity ≦ α2 (S24). α2 is an arbitrary setting value that can be set by the user for determining whether or not to perform energy saving control during heating operation. If the control device 20 determines in S24 that air conditioning processing capacity (air conditioning load) / rated capacity > α2, it sets the compressor 2 to be controlled in the first mode, which is normal operation (S26), and returns the process from the subroutine to the main routine. The first mode is a mode in which a grace period β2 is set.

If the control device 20 determines in S24 that the air conditioning processing capacity (air conditioning load)/rated capacity is equal to or less than α2, it sets the compressor 2 to be controlled in the second mode, which is an energy-saving operation (S25), and returns the process from the subroutine to the main routine. The second mode is a mode in which the refrigerant temperature is changed without providing a grace period β2.

During heating operation, the target condensation temperature (the temperature that is the target value of the refrigerant flowing through the indoor heat exchanger 6 functioning as a condenser) is used instead of the target evaporation temperature shown in FIG. 4. For example, referring to FIG. 4, the control device 20 maintains the temperature of the refrigerant in the indoor heat exchanger 6 functioning as a condenser at a target value a [°C] for a predetermined certain grace period β2 [min] after the first mode is turned on. The control device 20 controls the target value of the refrigerant temperature to be changed from a [°C] to b [°C] lower than a [°C] after the grace period β2 [min] has elapsed. The temperature of the refrigerant in the indoor heat exchanger 6 is changed from a [°C] to b [°C]. The control device 20 turns off the compressor 2 after maintaining the target value of the refrigerant temperature at b [°C] for a certain period of time. Thereafter, the control device 20 repeats the control of changing the target condensation temperature from a [°C] to b [°C], thereby repeatedly turning the compressor 2 on and off.

In the second mode, the control device 20 controls the refrigerant temperature of the indoor heat exchanger 6 to be changed from the target value a [°C] to b [°C] lower than a [°C] without providing a grace period β2 [min] after the thermo-on. As a result, the refrigerant temperature of the indoor heat exchanger 6 is changed from a [°C] to b [°C]. The control device 20 turns off the compressor 2 after maintaining the target value of the refrigerant temperature at b [°C] for a certain period of time. In the second mode, the grace period β2 [min] is not provided, and the period during which the target value of the refrigerant temperature is b [°C] is longer than in the first mode. In other words, in the second mode, the period during which the target value of the refrigerant temperature is controlled at b [°C] is longer than in the first mode, and the number of thermo-on and thermo-off of the compressor 2 is reduced accordingly. As a result, the air conditioning device 1 can extend the time to reach the target condensing temperature, and can perform energy-saving operation.

In the second embodiment, the grace period β2 [min] is, for example, 10 [min], a [°C] is, for example, 50 [°C], and b [°C] is, for example, 40 [°C]. In the air conditioning device 1 of the second embodiment, α2 is set, for example, within the range of 0.4≦α2≦0.7. When α2 is set in this manner, the number of thermo-on and thermo-off cycles of the compressor 2 in the second mode is roughly halved compared to the first mode. This allows the air conditioning device 1 of the second embodiment to extend the time it takes to reach the target condensing temperature, enabling energy-saving operation.

Embodiment 3.
FIG. 7 is a schematic diagram showing the configuration of an air conditioning system 100 in embodiment 3. The air conditioning system 100 is different in that the air conditioning device 1 is connected to a server device 40 via a network 9. The server device 40 is configured to include a CPU (Central Processing Unit) 41, a memory 42 (ROM (Read Only Memory) and RAM (Random Access Memory)), and an input/output device (not shown) for inputting and outputting various signals. The CPU 41 deploys a program stored in the ROM in the RAM or the like and executes it. The program stored in the ROM is a program in which the processing procedure of the server device 40 is written. This control is not limited to processing by software, and can also be processed by dedicated hardware (electronic circuitry).

In the air conditioning system 100, part of the processing executed in the control device 20 of the air conditioning device 1 is executed in the server device 40. The processing executed by the control device 20 of the air conditioning device 1 and the server device 40 will be described below. The control device 20 transmits detection data during operation of the refrigerant circuit 10 detected by multiple sensors to the server device 40. The server device 40 calculates the air conditioning processing capacity exerted by the air conditioning device 1 based on the received detection data according to the processing flow shown in Figures 5 and 6. If the ratio of the calculated air conditioning processing capacity to the rated capacity of the air conditioning device 1 is equal to or less than a preset threshold value (α1 or α2), the server device 40 creates first control data to operate the compressor 2 in the first mode, and if the ratio is greater than the preset threshold value, creates second control data to operate the compressor 2 in the second mode.

The server device 40 transmits the created first control data or second control data to the control device 20. If the received control data is the first control data, the control device 20 controls the compressor 2 to operate in the first mode, and if the received control data is the second control data, the control device 20 controls the compressor 2 to operate in the second mode. This reduces the processing burden on the control device 20.

<Modification>
In the air conditioner 1, the control device 20 controls the rotation speed of the compressor 2 to execute control in the first mode or the second mode. The control device 20 may control the rotation speed of the fan 8 in addition to the control of the compressor 2. The control device 20 may execute control to change the target value of the temperature of the refrigerant flowing through the indoor heat exchanger 6 from a first temperature to a second temperature higher than the first temperature by reducing the rotation speed of the fan 8 during cooling operation. The control device 20 may execute control to change the target value of the temperature of the refrigerant flowing through the indoor heat exchanger 6 from a first temperature to a second temperature lower than the first temperature by reducing the rotation speed of the fan 8 during heating operation. The air conditioner 1 may further use the fan 7 of the outdoor unit 12. The air conditioner 1 may execute control in the first mode or the second mode by controlling only the fans 7 and 8.

The air conditioning device 1 and the air conditioning system 100 have been described as not providing a grace period in the second mode. However, the air conditioning device 1 and the air conditioning system 100 may be configured to provide a grace period in the second mode that is shorter than that in the first mode.

<Summary>
The present disclosure relates to an air conditioner 1 including a refrigerant circuit 10 including an outdoor unit 12 and an indoor unit 11. The indoor unit 11 includes an indoor heat exchanger 6 through which a refrigerant flows. The outdoor unit 12 includes a compressor 2. The air conditioner 1 includes a plurality of sensors as a detection device that detects data during operation of the refrigerant circuit 10, and a control device 20 that controls the refrigerant circuit 10. The control device 20 calculates the air conditioning processing capacity exhibited by the air conditioner 1 from the data detected by the detection device, and controls the compressor 2 to operate in a first mode when the ratio of the calculated air conditioning processing capacity to the rated capacity of the air conditioner 1 is greater than a preset threshold, and controls the compressor 2 to operate in a second mode when the ratio is equal to or less than the preset threshold. The first mode is a control that changes the target value of the temperature of the refrigerant flowing through the indoor heat exchanger 6 from a first temperature to a second temperature different from the first temperature after a certain grace period has elapsed since the compressor 2 started operating. The second mode is a control in which no grace period is set from the start of operation of the compressor 2, or a grace period shorter than that in the first mode is set, and the target value of the temperature of the refrigerant flowing through the indoor heat exchanger 6 is changed from the first temperature to the second temperature.

Preferably, the indoor heat exchanger 6 functions as an evaporator during cooling operation. When the ratio becomes equal to or less than a preset threshold, the control device 20 executes control to change the target value of the temperature of the refrigerant flowing through the indoor heat exchanger 6 functioning as an evaporator in the second mode from a first temperature to a second temperature higher than the first temperature.

Preferably, the indoor unit 11 further includes a fan that supplies air for heat exchange with the refrigerant flowing through the indoor heat exchanger 6. The control device 20 executes control to change the evaporation temperature of the refrigerant from the first temperature to the second temperature by reducing the rotation speed of the fan 8.

Preferably, the indoor heat exchanger 6 functions as a condenser during heating operation. When the ratio becomes equal to or less than a preset threshold, the control device 20 executes control to change the condensation temperature of the refrigerant flowing through the indoor heat exchanger 6 functioning as a condenser in the second mode from a first temperature to a second temperature lower than the first temperature.

Preferably, the indoor unit 11 further includes a fan 8 that supplies air for heat exchange with the refrigerant flowing through the indoor heat exchanger 6. The control device 20 executes control to change the target value of the refrigerant temperature from the first temperature to the second temperature by reducing the rotation speed of the fan 8.

The present disclosure relates to an air conditioning system 100 including an air conditioner 1 including a refrigerant circuit 10 including an outdoor unit 12 and an indoor unit 11, and a server device 40 connected to the air conditioner 1 via a network 9. The indoor unit 11 includes an indoor heat exchanger 6 through which a refrigerant flows. The outdoor unit 12 includes a compressor 2. The air conditioner 1 includes a plurality of sensors as a detection device that detects data during operation of the refrigerant circuit 10, and a control device 20 that transmits detection data of the detection device to the server device 40 and controls the refrigerant circuit 10 based on control data received from the server device 40. The server device 40 calculates the air conditioning processing capacity exerted by the air conditioner 1 based on the detection data, and creates first control data to operate the compressor 2 in a first mode when the ratio of the calculated air conditioning processing capacity to the rated capacity of the air conditioner 1 is greater than a preset threshold, and creates second control data to operate the compressor 2 in a second mode when the ratio is equal to or less than a preset threshold. The first control data is data for changing the target value of the temperature of the refrigerant flowing through the indoor heat exchanger 6 from the first temperature to a second temperature different from the first temperature after a certain grace period has elapsed since the start of operation of the compressor 2. The second control data is data for changing the target value of the temperature of the refrigerant flowing through the indoor heat exchanger 6 from the first temperature to the second temperature without providing a grace period from the start of operation of the compressor 2 or by providing a grace period shorter than that in the first mode.

Thus, according to the air conditioning apparatus 1 and air conditioning system 100 disclosed herein, the compressor 2 is operated in the first mode or the second mode depending on whether the ratio of the calculated air conditioning processing capacity to the rated capacity of the air conditioning apparatus 1 is below a preset threshold value, so that energy saving effects can be obtained even when an air conditioning apparatus 1 with a low air conditioning load rate is used.

The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present disclosure is indicated by the claims, not by the description of the embodiments above, and is intended to include all modifications within the meaning and scope of the claims.

1 Air conditioning device, 2 Compressor, 3 Four-way valve, 4 Outdoor heat exchanger, 5 Expansion valve, 6 Indoor heat exchanger, 7, 8 Fan, 9 Network, 10 Refrigerant circuit, 11 Indoor unit, 12 Outdoor unit, 20 Control device, 22, 42 Memory, 31a, 31b Pressure sensor, 32a, 32b, 33a, 33b Refrigerant temperature sensor, 40 Server device, 100 Air conditioning system, 200 Indoor unit.

Claims (6)

An air conditioning apparatus having a refrigerant circuit including an outdoor unit and an indoor unit,
The indoor unit includes an indoor heat exchanger through which a refrigerant flows,
The outdoor unit includes a compressor,
The air conditioning device includes:
A detection device for detecting data during operation of the refrigerant circuit;
A control device for controlling the refrigerant circuit,
The control device includes:
Calculating the air conditioning processing capacity exhibited by the air conditioner from the data detected by the detection device;
When a ratio of the calculated air conditioning processing capacity to a rated capacity of the air conditioner is greater than a preset threshold, the compressor is controlled to operate in a first mode, and when the ratio is equal to or less than a preset threshold, the compressor is controlled to operate in a second mode;
The first mode is a control in which a target value of a temperature of the refrigerant flowing through the indoor heat exchanger is changed from a first temperature to a second temperature different from the first temperature after a certain grace period has elapsed since the start of operation of the compressor,
The second mode is a control in which the target value of the temperature of the refrigerant flowing through the indoor heat exchanger is changed from the first temperature to the second temperature without setting the grace period from the start of operation of the compressor or by setting a grace period shorter than that in the first mode. The indoor heat exchanger functions as an evaporator during cooling operation,
The air conditioning apparatus of claim 1, wherein when the ratio becomes equal to or lower than a predetermined threshold value, the control device executes control to change a target value of the temperature of the refrigerant flowing through the indoor heat exchanger functioning as the evaporator in the second mode from the first temperature to the second temperature which is higher than the first temperature. The indoor unit further includes a fan that supplies air for exchanging heat with the refrigerant flowing through the indoor heat exchanger,
The air-conditioning apparatus according to claim 2 , wherein the control device executes control to change the evaporation temperature of the refrigerant from the first temperature to the second temperature by reducing a rotation speed of the fan. The indoor heat exchanger functions as a condenser during heating operation,
The air conditioning apparatus of claim 1, wherein when the ratio becomes equal to or lower than a preset threshold value, the control device executes control to change the condensation temperature of the refrigerant flowing through the indoor heat exchanger functioning as the condenser in the second mode from the first temperature to the second temperature which is lower than the first temperature. The indoor unit further includes a fan that supplies air for exchanging heat with the refrigerant flowing through the indoor heat exchanger,
The air-conditioning apparatus according to claim 4 , wherein the control device executes control to change the target value of the refrigerant temperature from the first temperature to the second temperature by reducing a rotation speed of the fan. An air conditioner having a refrigerant circuit including an outdoor unit and an indoor unit;
A server device connected to the air conditioning apparatus via a network,
The indoor unit includes an indoor heat exchanger through which a refrigerant flows,
The outdoor unit includes a compressor,
The air conditioning device includes:
A detection device for detecting data during operation of the refrigerant circuit;
a control device that transmits detection data of the detection device to the server device and controls the refrigerant circuit based on control data received from the server device,
The server device includes:
Calculating the air conditioning processing capacity of the air conditioner based on the detection data;
creating first control data to operate the compressor in a first mode when a ratio of the calculated air conditioning processing capacity to a rated capacity of the air conditioner is greater than a preset threshold, and creating second control data to operate the compressor in a second mode when the ratio is equal to or less than a preset threshold;
the first control data is data for changing a target value of a temperature of the refrigerant flowing through the indoor heat exchanger from a first temperature to a second temperature different from the first temperature after a certain grace period has elapsed since the compressor started operating,
The second control data is data for changing a target value of a temperature of the refrigerant flowing through the indoor heat exchanger from the first temperature to the second temperature without setting the grace period from the start of operation of the compressor or by setting a grace period shorter than that in the first mode.

Images