JP5795025B2 - Refrigeration cycle equipment - Google Patents

Description

  The present invention relates to a refrigeration cycle apparatus having a refrigerant circuit for circulating a refrigerant.

  In a refrigeration cycle apparatus that has a refrigerant circuit that circulates refrigerant and performs a refrigeration cycle, the compressor itself deteriorates when an operation period elapses for a long time after the apparatus is installed. Specifically, refrigerant leakage or the like from the high pressure side to the low pressure side occurs inside the compressor due to wear of the compression mechanism portion of the compressor. When such deterioration occurs, the compression efficiency is lowered and the COP (coefficient of performance) of the refrigeration cycle is lowered.

  Conventionally, even if the compressor deteriorates in this way, there is no way of directly knowing it, and it is left without being updated until a situation where it is apparently abnormal, or until the compressor completely fails. There were many cases. Accordingly, several compressor deterioration detection techniques for detecting deterioration of the compressor in the refrigerant circuit in the refrigeration cycle apparatus having the refrigerant circuit have been proposed.

  As a prior art, in a refrigeration apparatus that performs a vapor compression refrigeration cycle, operation is performed with the same predetermined operating conditions at each predetermined time, and the compressor suction temperature, the compressor suction pressure, and the compressor discharge temperature are A refrigeration system has been proposed in which a polytropic index or polytropic efficiency is obtained based on the compressor discharge pressure and the deterioration of the compressor is judged from the change over time (for example, see Patent Document 1).

  As another conventional technique, an air conditioner that operates in a state where variable parts (hereinafter referred to as actuators) such as a compressor, a blower, and an electric valve are fixed in a specific state and estimates a failure location. Has been proposed (see, for example, Patent Document 2).

JP-A-2003-214735 (for example, pages 10-14, FIGS. 10-30, etc.) Japanese Patent Laying-Open No. 2006-090614 (for example, page 3, FIG. 2, etc.)

  In the prior art described in the above-mentioned Patent Document 1, by making the deterioration determination with the same predetermined operating condition at every predetermined time, the polytropic index is supposed to be constant if the compressor is in a normal state. The deterioration of the compressor is determined depending on whether or not the fluctuation occurs. However, in such a technique, when fluctuations in ambient environmental conditions such as ambient air temperature continuously occur, it takes time to reach the refrigerant state, which is the same operating condition in which deterioration of the compressor can be determined. There was a problem that the time required for the deterioration determination would be long.

  In the prior art described in Patent Document 2, the failure of the actuator is estimated after the operation for fixing the actuator for controlling the refrigerant circuit of the air conditioner. However, such a technique has a problem that the temperature and pressure of the refrigerant fluctuate due to fluctuations in ambient environmental conditions such as the ambient air temperature, the operation state of the refrigerant circuit is not stable, and accurate failure determination cannot be performed. .

  The present invention has been made to solve the above-described problems, and avoids misjudgment due to fluctuations in ambient environmental conditions such as ambient air temperature to improve the accuracy of the compressor degradation determination and reduce the compressor degradation. An object of the present invention is to obtain a refrigeration cycle apparatus that realizes shortening of diagnosis time in diagnosis.

The refrigeration cycle apparatus according to the present invention includes a compressor that compresses a refrigerant, a condenser that condenses the refrigerant compressed by the compressor, a decompressor that decompresses the refrigerant condensed by the condenser, and the decompressor. A refrigerant circuit configured to connect an evaporator for evaporating the decompressed refrigerant to circulate the refrigerant, a condenser blower for blowing air to the condenser, an evaporator blower for blowing air to the evaporator, An operating state quantity detecting means for detecting an operating state quantity of the refrigerant circuit; an operating capacity of the compressor; a rotational speed of the condenser blower; a rotational speed of the evaporator blower; and an opening of the decompressor. The control target value of the operating state quantity of the refrigerant circuit for controlling the degree is set, and the operating capacity of the compressor, the condenser air flow according to the deviation between the operating state quantity at the control target value and the current operating state quantity Dress The refrigerant state control operation for controlling the refrigerant state of the refrigerant circuit by determining the amount of change of the rotation number of the evaporator, the rotation number of the evaporator blower, and the opening amount of the decompression device, and by the refrigerant state control operation From the refrigerant state of the refrigerant circuit and the control target value, the operating capacity of the compressor, the rotational speed of the condenser blower, the rotational speed of the evaporator blower, and the opening of the decompressor are determined. A control index, a determination index calculation section for calculating a determination index used for determining the deterioration of the compressor based on the operation state quantity detected by the operation state quantity detection means, and an operation state quantity detected by the operation state quantity detection means A reference value setting unit that sets a deterioration determination reference value corresponding to the current operating state based on the operation capacity of the compressor in the control unit when determining deterioration of the compressor, Number of revolutions, The determination index calculated by the determination index calculation unit and the reference value setting unit when the rotational speed of the generator blower and the opening of the decompression device are determined and the operating state of the refrigerant circuit is in a steady state A deterioration determination unit that compares the deterioration determination reference value set by the control unit to determine whether or not the compressor has deteriorated, and the control unit performs the compression during the refrigerant state control operation. Machine, the condenser blower, the evaporator blower, and the decompressor are operated at different intervals .

According to the refrigeration cycle apparatus according to the present invention, by determining the actuator adjustment amount in the refrigerant state control operation according to the operation state amount deviation with respect to the control target value, the hunting state in which the operation state amount greatly varies with respect to the target state. Thus, the steady state can be realized early and the diagnosis time for the compressor deterioration can be shortened.
Further, according to the refrigeration cycle apparatus according to the present invention, the actuator state of the refrigeration cycle apparatus is determined so as to be in a predetermined operation state by the refrigerant state control operation, and the compressor deterioration is determined in the steady state of the refrigerant circuit. In addition, it is possible to avoid erroneous determination due to fluctuations in ambient environmental conditions such as ambient air temperature, and to realize highly accurate compressor deterioration determination.

It is a lineblock diagram of the refrigerating cycle device concerning an embodiment of the invention. It is a control block diagram of the refrigerating cycle device concerning an embodiment of the invention. It is a Ph diagram which shows the state transition of the refrigerant | coolant of the refrigerating-cycle apparatus which concerns on embodiment of this invention. It is a flowchart which shows the flow of the compressor deterioration determination in the refrigeration cycle apparatus which concerns on embodiment of this invention. It is a figure which shows an example of the function table | surface of determination criterion value (delta) m in the refrigerating-cycle apparatus which concerns on embodiment of this invention. It is a flowchart which shows the flow of the refrigerant | coolant state control operation mode of the refrigerating-cycle apparatus which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in the following drawings including FIG. 1, the relationship of the size of each component may be different from the actual one. Further, in the following drawings including FIG. 1, the same reference numerals denote the same or equivalent parts, and this is common throughout the entire specification. Furthermore, the forms of the constituent elements shown in the entire specification are merely examples, and are not limited to these descriptions.

  FIG. 1 is a configuration diagram of a refrigeration cycle apparatus 100 according to an embodiment of the present invention. FIG. 2 is a control block diagram of the refrigeration cycle apparatus 100. Based on FIG.1 and FIG.2, the structure of the refrigerating-cycle apparatus 100 is demonstrated. This refrigeration cycle apparatus 100 is used in, for example, an air conditioner, a refrigerator, a freezer, a vending machine, a showcase, and the like.

  The refrigeration cycle apparatus 100 includes an outdoor unit A, a plurality of indoor units B1, and an indoor unit B2, which are connected by a refrigerant pipe 50. The outdoor unit A has a compressor 1, a four-way valve 2, and an outdoor heat exchanger 3. The indoor unit B1 includes an indoor heat exchanger 5a and an expansion valve 4a. The indoor unit B2 includes an indoor heat exchanger 5b and an expansion valve 4b. Then, the refrigerant is supplied by the compressor 1, the four-way valve 2, the outdoor heat exchanger 3, the expansion valve 4 (expansion valve 4a, expansion valve 4b), and the indoor heat exchanger 5 (indoor heat exchanger 5a, indoor heat exchanger 5b). A circulating refrigerant circuit is formed.

  The outdoor heat exchanger 3 is provided with an outdoor blower 6 that blows air. Similarly, the indoor heat exchanger 5a and the indoor heat exchanger 5b are also provided with an indoor blower 7a and an indoor blower 7b for blowing air. In the following description, the indoor units B1 and B2 may be collectively referred to as an indoor unit B. Similarly, the indoor heat exchangers 5a and 5b may be collectively referred to as the indoor heat exchanger 5. Similarly, the expansion valves 4a and 4b may be collectively referred to as the expansion valve 4. Similarly, the indoor air blowers 7a and 7b may be collectively referred to as the indoor air blower 7.

(Compressor)
The compressor 1 sucks refrigerant and compresses the refrigerant to a high temperature and high pressure state. The compressor 1 is composed of a positive displacement compressor capable of changing an operating capacity (frequency). Control methods for varying the operating capacity include, for example, a method of driving a motor controlled by an inverter and a method of using a slide valve. In FIG. 1, only one compressor 1 is provided. However, the present invention is not limited to this, and two or more compressors may be connected in parallel or in series.

(valve)
A valve 11a and a valve 11b are provided at the piping outlet of the outdoor unit A. The valves 11a and 11b are configured by valves that can be opened and closed, such as ball valves, on-off valves, and operation valves. In the valve 11a and the valve 11b, the outdoor unit A and the indoor unit B can be appropriately separated. The valves 11a and 11b may be collectively referred to as the valve 11.

(Four-way valve)
The four-way valve 2 is a valve having a function of switching the direction of refrigerant flow. During the cooling operation, the refrigerant flow path is switched so that the discharge side of the compressor 1 and the outdoor heat exchanger 3 are connected and the connection pipe between the suction side of the compressor 1 and the indoor unit B is connected (FIG. 1). Solid line of the four-way valve 2 shown). During the heating operation, the refrigerant flow path is switched so that the connection pipe between the discharge side of the compressor 1 and the indoor unit B is connected, and the suction side of the compressor 1 and the outdoor heat exchanger 3 are connected (FIG. 1). The broken line of the four-way valve 2 shown).

(Outdoor heat exchanger)
The outdoor heat exchanger 3 functions as a condenser (heat radiator) during the cooling operation and as an evaporator during the heating operation, and performs heat exchange between the air supplied from the outdoor blower 6 and the refrigerant, and uses the refrigerant. It is condensed or liquefied. The outdoor heat exchanger 3 may be constituted by, for example, a cross fin type fin-and-tube heat exchanger composed of a heat transfer tube and a large number of fins.

  However, the outdoor heat exchanger 3 may be determined according to the use application of the refrigeration cycle apparatus 100. For example, a large number of thin plates may be arranged at intervals, the peripheral edge portion may be sealed, and the space formed between the thin plates may be configured by a plate heat exchanger that alternately serves as a refrigerant flow path and a water flow path. In the case where a plate heat exchanger is used and the heat exchange medium is a fluid such as water, for example, the outdoor heat exchanger 3 removes the heat exchange medium using a delivery device (not shown) such as a pump. To supply. The heat exchange medium is not limited to water, and may be another fluid as long as it exhibits a similar action.

(Outdoor fan)
The outdoor air blower 6 is attached to the outdoor heat exchanger 3 and blows air to the outdoor heat exchanger 3. The outdoor blower 6 is a fan that blows air, and includes a centrifugal fan, a multiblade fan, and the like that are driven by a DC motor (not shown), and is capable of adjusting the amount of blown air. .
When the outdoor heat exchanger 3 functions as a condenser, the outdoor blower 6 functions as a “condenser blower”.
When the outdoor heat exchanger 3 functions as an evaporator, the outdoor blower 6 functions as an “evaporator blower”.

(Expansion valve)
The expansion valve 4 is a decompression device with a variable opening, and has a function of reducing the pressure of the refrigerant flowing through the refrigerant pipe 50. The expansion valve 4 may be an electronic expansion valve that can adjust the opening of the throttle by a stepping motor (not shown) so that the refrigerant flow rate can be adjusted.

(Indoor heat exchanger)
The indoor heat exchanger 5 functions as an evaporator during the cooling operation, and functions as a condenser (heat radiator) during the heating operation, and performs heat exchange between the air supplied from the indoor blower 7 and the refrigerant. Heating air or cooling air to be supplied to the air. The indoor heat exchanger 5 may be constituted by, for example, a cross fin type fin-and-tube heat exchanger constituted by heat transfer tubes and a large number of fins.

  However, the indoor heat exchanger 5 may be determined according to the intended use of the refrigeration cycle apparatus 100. For example, a large number of thin plates may be arranged at intervals, the peripheral edge portion may be sealed, and the space formed between the thin plates may be configured by a plate heat exchanger that alternately serves as a refrigerant flow path and a water flow path. When a plate heat exchanger is used and the heat exchange medium is a fluid such as water, for example, the heat exchange medium is transferred to the indoor heat exchanger 5 using a delivery device (not shown) such as a pump. To supply. The heat exchange medium is not limited to water, and may be another fluid as long as it exhibits a similar action.

(Indoor air blower)
The indoor air blower 7 is attached to the indoor heat exchanger 5 and blows air to the indoor heat exchanger 5. The indoor blower 7 is a fan that blows air, and includes a centrifugal fan, a multiblade fan, and the like driven by a DC motor (not shown), and is capable of adjusting the amount of blown air. .
When the indoor heat exchanger 5 functions as a condenser, the indoor blower 7 functions as a “condenser blower”.
When the indoor heat exchanger 5 functions as an evaporator, the indoor blower 7 functions as an “evaporator blower”.

  In the present embodiment, a configuration in which there are two indoor units B will be described as an example, but the number of connected indoor units B is not particularly limited. For example, the number of indoor units B may be one, or a plurality of three or more units may be connected. Moreover, even if each capacity | capacitance of the some indoor unit B differs from large to small, all may be the same capacity | capacitance.

(Refrigerant)
The kind of the refrigerant circulating through the refrigerant circuit of the refrigeration cycle apparatus 100 is not particularly limited, and any refrigerant can be used. As the refrigerant to be circulated in the refrigerant circuit of the refrigeration cycle apparatus 100, for example, natural refrigerants such as carbon dioxide (CO ₂ ), hydrocarbons, helium, and chlorine such as alternative refrigerants such as R407C and R404A as well as R410A can be used. A refrigerant not included may be used.

(Other)
In the present embodiment, a case will be described in which a four-way valve 2 is provided to configure a refrigerant circuit capable of switching between heating operation and cooling operation, but the present invention is not limited to this. For example, only the cooling operation or only the heating operation may be performed without providing the four-way valve 2. Further, as a substitute for the four-way valve 2, for example, a plurality of two-way valves or three-way valves may be used so that the refrigerant flow can be switched in the same manner.

Subsequently, the sensors and the control unit will be described.
As shown in FIG. 1, the outdoor unit A includes a discharge temperature sensor 41, a suction temperature sensor 42, a discharge pressure sensor 31, and a suction pressure sensor 32 as operation state amount detection means.
The outdoor unit A includes an outdoor intake air temperature sensor 40 as an outside air temperature detecting means for detecting the outside air temperature.

The discharge temperature sensor 41 is installed on the discharge side of the compressor 1 and detects the temperature of the refrigerant discharged from the compressor 1.
The suction temperature sensor 42 is installed on the suction side of the compressor 1 and detects the temperature of the refrigerant sucked into the compressor 1.

The discharge pressure sensor 31 is installed on the discharge side of the compressor 1 and detects the pressure of the refrigerant discharged from the compressor 1.
The suction pressure sensor 32 is installed on the suction side of the compressor 1 and detects the pressure of the refrigerant sucked into the compressor 1.
The condensation temperature CT of the refrigeration cycle can be obtained by converting the pressure detected by the discharge pressure sensor 31 into the saturation temperature, and the refrigeration cycle can be obtained by converting the pressure detected by the suction pressure sensor 32 into the saturation temperature. The evaporation temperature ET can be determined.

Note that the installation positions of the discharge pressure sensor 31 and the discharge temperature sensor 41 are not limited to the illustrated positions, and may be provided anywhere as long as the section extends from the discharge side of the compressor 1 to the four-way valve 2. It may be done.
In addition, the installation positions of the suction pressure sensor 32 and the suction temperature sensor 42 are not limited to the illustrated positions, and may be provided anywhere in the section from the four-way valve 2 to the suction side of the compressor 1. It may be done.

The outdoor intake air temperature sensor 40 detects the air temperature taken into the outdoor heat exchanger 3, and detects the ambient air temperature of the outdoor unit A in which the outdoor heat exchanger 3 is installed.
Note that the installation position of the outdoor intake air temperature sensor 40 is not limited to the illustrated position, and can be installed anywhere as long as the temperature of the air taken into the outdoor heat exchanger 3 can be detected. Good. For example, the outdoor intake air temperature sensor 40 may be installed outside the outdoor unit A.

As shown in FIG. 1, the indoor unit B2 has a gas side temperature sensor 44 (a gas side temperature sensor 44a, a gas side temperature sensor 44b), a liquid side temperature at an inlet / outlet of the indoor heat exchanger 5 as an operating state quantity detection unit. Sensors 45 (liquid side temperature sensor 45a, liquid side temperature sensor 45b) are provided.
The indoor unit B includes an indoor intake air temperature sensor 43 (indoor intake air temperature sensor 43a, indoor intake air temperature sensor 43b) as room temperature detection means for detecting the indoor temperature.

The gas side temperature sensor 44 detects the temperature of the refrigerant flowing out from the indoor heat exchanger 5 during the cooling operation.
The gas side temperature sensor 44 provided in the indoor unit B1 is illustrated as a gas side temperature sensor 44a, and the gas side temperature sensor 44 provided in the indoor unit B2 is illustrated as a gas side temperature sensor 44b.

The liquid side temperature sensor 45 detects the temperature of the refrigerant flowing out from the indoor heat exchanger 5 during the heating operation.
The liquid side temperature sensor 45 provided in the indoor unit B1 is illustrated as a liquid side temperature sensor 45a, and the liquid side temperature sensor 45 provided in the indoor unit B2 is illustrated as a liquid side temperature sensor 45b.

The indoor intake air temperature sensor 43 detects the air temperature taken into the indoor heat exchanger 5 and detects the ambient air temperature of the indoor unit.
The indoor intake air temperature sensor 43, which is provided in the indoor unit B1 and detects the air temperature taken into the indoor heat exchanger 5a, is used as the indoor intake air temperature sensor 43a, and is provided in the indoor unit B2 to the indoor heat exchanger 5b. An indoor intake air temperature sensor 43 that detects the intake air temperature is illustrated as an indoor intake air temperature sensor 43b.

  FIG. 2 illustrates a connection configuration of the control unit 30 that performs measurement control of the refrigeration cycle apparatus 100 and sensors and actuators connected thereto.

  The control unit 30 is built in, for example, the outdoor unit A, and includes a measurement unit 30a, a calculation unit 30b, a drive unit 30c, a storage unit 30d, and a determination unit 30e. The control unit 30 functionally realizes the “control unit”, “determination index calculation unit”, “reference value setting unit”, and “degradation determination unit” of the present invention.

  The measurement unit 30a receives operating state quantities detected from various sensors (pressure sensor and temperature sensor), and measures pressure and temperature. The measuring unit 30a also detects the operating capacity of the compressor 1 as the operating state quantity. The operation state quantity measured by the measurement unit 30a is input to the calculation unit 30b.

  The calculation unit 30b calculates, for example, a refrigerant physical property value (saturation pressure, saturation temperature, enthalpy, etc.) using a formula given in advance based on the operation state quantity measured by the measurement unit 30a. Moreover, the calculating part 30b performs arithmetic processing, such as calculating the determination parameter | index for performing deterioration determination of the compressor 1, based on the driving | running state amount measured by the measurement part 30a.

  The drive unit 30c drives or stops the compressor 1, the expansion valve 4a, the expansion valve 4b, the outdoor blower 6, the indoor blower 7a, the indoor blower 7b, and the like based on the calculation result of the calculation unit 30b. .

  The storage unit 30d stores a result obtained by the calculation unit 30b, a predetermined constant, a functional expression for calculating a physical property value (saturation pressure, saturation temperature) of the refrigerant, a function table (table), and the like. These stored contents in the storage unit 30d can be referred to and rewritten as necessary. The storage unit 30d further stores a control program, and the control unit 30 controls the refrigeration cycle apparatus 100 according to the program in the storage unit 30d.

  The determination unit 30e performs processing such as comparison and determination based on the result obtained by the calculation unit 30b. The determination unit 30e performs compressor deterioration determination for determining deterioration of the compressor 1 by performing threshold determination based on the deterioration determination index obtained by the calculation unit 30b. Details of the compressor deterioration determination method will be described later.

  The measurement unit 30a, the calculation unit 30b, the drive unit 30c, and the determination unit 30e are configured by, for example, a microcomputer, and the storage unit 30d is configured by a semiconductor memory or the like.

Further, the control unit 30 displays and outputs the processing result of the microcomputer by an LED, a monitor or the like, or outputs information to a remote place by a communication means (not shown) such as a telephone line, a LAN line, or a radio. An output unit 30g is connected.
The control unit 30 is further connected to an input unit 30f for inputting communication data information from a communication means (not shown) such as an operation input from a remote controller or switches on the board, a telephone line, a LAN line, or wireless. .

  In the configuration example of the present embodiment, the control unit 30 is built in the outdoor unit A, but the present invention is not limited to this. By providing a main control unit in the outdoor unit A and a sub control unit having a part of the function of the control unit in the indoor unit B1 and the indoor unit B2, and performing data communication between the main control unit and the sub control unit It is good also as a structure which performs a cooperation process, the structure which installs the control part which has all the functions in indoor unit B1 and indoor unit B2, or the form which separately arranges a control part in these.

《Driving operation (cooling mode)》
Next, the operation operation in the cooling mode, which is a typical operation mode in the refrigeration cycle apparatus 100 and has the same refrigerant flow as the compressor deterioration determination mode described later, will be described with reference to FIG. In the cooling mode, the four-way valve 2 is in the state indicated by the solid line in FIG. 1, that is, the discharge side of the compressor 1 is connected to the outdoor heat exchanger 3, and the suction side of the compressor 1 is the indoor heat exchanger 5a. It is in a state of being connected to the exchanger 5b.

  The high-temperature and high-pressure gas refrigerant discharged from the compressor 1 reaches the outdoor heat exchanger 3 that is a condenser via the four-way valve 2, and the refrigerant is condensed and liquefied by the blowing action of the outdoor air blower 6. It becomes. The condensed and liquefied high-temperature and low-pressure refrigerant is decompressed by the expansion valve 4a and the expansion valve 4b to become a two-phase refrigerant, and is sent to the indoor heat exchanger 5a and the indoor heat exchanger 5b, respectively. The decompressed two-phase refrigerant is evaporated by the blowing action of the indoor blower 7a and the indoor blower 7b in the indoor heat exchangers 5a and 5b, which are evaporators, and becomes a low-pressure gas refrigerant. The low-pressure gas refrigerant is sucked into the compressor 1 via the four-way valve 2.

  Here, the opening degree of the expansion valve 4a and the expansion valve 4b is adjusted so that the refrigerant superheat degree at the outlet of the indoor heat exchanger 5a and the indoor heat exchanger 5b becomes a predetermined value, respectively. The flow rate of the refrigerant flowing through the heat exchanger 5b is controlled. Therefore, the low-pressure gas refrigerant evaporated in the indoor heat exchangers 5a and 5b has a predetermined degree of superheat. The refrigerant superheat degree at the outlets of the indoor heat exchanger 5a and the indoor heat exchanger 5b is a saturation temperature conversion value (evaporation temperature) of the pressure detection value of the suction pressure sensor 32 from the detection values of the gas side temperature sensor 44a and the gas side temperature sensor 44b. Detection is performed by subtracting (ET). Thus, the refrigerant | coolant of the flow volume according to the driving | running load requested | required in the air-conditioning space in which indoor unit B1 and indoor unit B2 were installed flows into the indoor heat exchanger 5a and the indoor heat exchanger 5b.

《Principle of compressor deterioration judgment method》
A compressor deterioration determination method executed by the refrigeration cycle apparatus 100 will be described. In this compressor deterioration determination method, the operation state quantity (determination reference value) in a predetermined refrigerant condition at the beginning of installation (reference time) and the operation state quantity (in the same refrigerant condition as in the reference time when a predetermined period has elapsed since installation) And the deterioration of the compressor 1 is determined. The principle of this compressor deterioration determination will be described with reference to FIG. FIG. 3 is a Ph diagram illustrating the state transition of the refrigerant in the refrigeration cycle apparatus 100.

  In the vapor compression refrigeration cycle, which is the operating principle of the refrigeration cycle apparatus 100, the refrigerant was compressed from point A to point B in the compression stroke as shown in the Mollier diagram (Ph diagram) shown in FIG. Then, it cools to C point in a condensation process. The refrigerant cooled to the point C is depressurized to the point D in the expansion stroke and is heated to the point A in the evaporation stroke, and circulates in the refrigerant circuit.

  On the other hand, if the compressor 1 deteriorates after a long time (for example, several years) has elapsed since installation, even if the suction refrigerant state (point A) of the compressor 1 is the same, the curve of the compression stroke changes and the discharge side refrigerant state Changes and point B moves to point B ′. In this case, the enthalpy difference in the compressor 1 corresponding to the compressor input is Δhc at the time of installation, but increases to Δhc ′, and the compressor efficiency is lowered.

  In such a refrigeration cycle, the presence or absence of deterioration of the compressor 1 can be determined based on the change in the operating state amount accompanying the change in the compression stroke curve when the compressor efficiency is reduced as described above. That is, as the efficiency of the compressor 1 decreases, a phenomenon occurs in which the discharge refrigerant temperature of the compressor 1 in the operating state amount increases approximately monotonously. Therefore, in the refrigeration cycle apparatus 100, the compressor deterioration determination is performed based on such a change characteristic of the operation state quantity with respect to the compressor efficiency.

《Compressor deterioration judgment mode》
FIG. 4 is a flowchart showing the flow of the compressor deterioration determination in the refrigeration cycle apparatus 100. Hereinafter, the flow of processing in the compressor deterioration determination of the refrigeration cycle apparatus 100 will be described. Detailed operation description in each step will be described later. In the compressor deterioration determination mode, the four-way valve 2 is switched to the solid line side in FIG. 1, and the compressor deterioration determination is performed using the refrigerant circuit as the refrigerant flow in the cooling operation.

  After starting the compressor deterioration determination flow, the control unit 30 becomes a condition for controlling each actuator of the refrigeration cycle apparatus 100 (here, the compressor 1, the expansion valve 4, the outdoor blower 6, and the indoor blower 7 are applicable). A control target value of the operation state quantity is set (step S1).

As the control target value, for example, the operating capacity F for the compressor 1, the refrigerant condensation temperature CT for the outdoor blower 6, the refrigerant evaporation temperature ET for the indoor blower 7, and the evaporator (here, cooling) for the expansion valve 4 The target value for the outlet evaporator superheat degree SH at the outlet is set for the indoor heat exchanger 5 for operation. Specifically, for example, the control target value F _m = 78 Hz for the operating capacity F, the control target value CT _m = 42 ° C. for the condensation temperature CT, the control target value ET _m = 2 ° C. for the evaporation temperature ET, and the evaporator at the evaporator outlet The control target value SH _m = 2 ° C. of the outlet refrigerant superheat degree SH is set.

  Then, the control unit 30 operates the refrigeration cycle apparatus 100 in the refrigerant state control operation mode based on the control target value set in step S1 (step S2). In the refrigerant state control operation mode, the operation capacity of the compressor 1, the rotational speed of the outdoor air blower 6, and the rotational speed of the indoor air blower 7 so that the refrigerant state of the refrigerant circuit satisfies the control target value set in step S1. And the opening degree of the expansion valve 4 is controlled. The operation method in the refrigerant state control operation mode will be described later.

Subsequently, the control unit 30 determines whether or not the refrigerant state of the refrigerant circuit when the refrigerant state control operation mode is activated satisfies a predetermined condition with respect to the control target value (step S3). Here, it is assumed that the predetermined condition is, for example, a case where the operation state amount of the refrigerant circuit is within a predetermined range for a predetermined time with respect to the control target value of each actuator. Specifically, when the operating capacity F reaches the control target value F _m for the compressor 1, the refrigerant condensation temperature CT for the outdoor blower 6 is within the control target value CT _m ± 0.5 ° C. for 5 minutes. When it continues, when the evaporation temperature ET of the refrigerant for the indoor air blower 7 continues within the control target value ET _m ± 0.5 ° C. for 5 minutes, the evaporator outlet refrigerant superheat degree SH at the evaporator outlet for the expansion valve 4 Is assumed to be within the control target value SH _m ± 2.0 ° C. for 5 minutes.

  If the operation state of the refrigerant circuit does not satisfy the condition (step S3; NO), the process returns to step S2 to continue the refrigerant state control operation. If the operation state of the refrigerant circuit satisfies the condition (step S3; YES), each actuator state, that is, the operation capacity of the compressor 1, the rotational speed of the outdoor blower 6, the rotational speed of the indoor blower 7, and Then, the opening degree of the expansion valve 4 is determined and set in a fixed state (step S4).

  After the actuator state is determined, the measurement unit 30a detects the operation state amount of the refrigerant circuit (step S5). The operating state quantities here are, for example, the refrigerant condensation temperature CT, the refrigerant evaporation temperature ET, the compressor intake refrigerant superheat degree SHs of the compressor 1, the compressor 1 discharge refrigerant temperature Td, and the compressor 1 intake refrigerant temperature Ts. Etc. The detected value of the discharge temperature sensor 41 is used for the discharge refrigerant temperature Td. The value detected by the suction temperature sensor 42 is used as the suction refrigerant temperature Ts. The refrigerant condensing temperature CT is a value converted to the saturation temperature of the discharge pressure Pd, which is a detected value of the discharge pressure sensor 31, and the evaporation temperature ET of the refrigerant is converted to a saturation temperature of the suction pressure Ps, which is a detected value of the suction pressure sensor 32. Use the value. The compressor intake refrigerant superheat degree SHs uses a value obtained by subtracting the intake refrigerant temperature Ts and the evaporation temperature ET.

  Further, as the operation state quantity, not only the instantaneous value in the trend data but also the average value for a predetermined time, for example, every 10 minutes may be detected.

  The determination unit 30e determines whether or not the operation state of the refrigerant circuit is a steady state based on the detected operation state amount (step S6). As a steady state determination method, for example, as the steady state determination conditions, all five operation state quantities of the condensation temperature CT, the evaporation temperature ET, the compressor intake refrigerant superheat degree SHs, the discharge refrigerant temperature Td, and the intake refrigerant temperature Ts are respectively predetermined. A steady state is determined when the deviation between the average value of the time-lapse data over time (for example, 10 minutes) and the instantaneous value of the time-lapse data at the same time is within a predetermined value (for example, ± 0.5 ° C.). When the stationary determination condition is not satisfied (step S6; NO), the process returns to step S5. When the steady determination condition is satisfied (step S6; YES), the process proceeds to step S7.

  Next, the computing unit 30b calculates the current determination index δ using the detected operating state quantity (step S7). For example, a value obtained by subtracting the suction refrigerant temperature Ts from the discharge refrigerant temperature Td of the compressor 1 is used as the determination index δ. As the determination index δ, an average value for a predetermined time (for example, 10 minutes) calculated in a steady state is used.

  Next, a determination reference value δm that serves as a deterioration determination reference for the compressor 1 is set (step S8). The determination reference value δm is a value corresponding to the determination index δ in the initial state in which the compressor 1 is not deteriorated, and a function of the determination reference value stored in advance in the storage unit 30d is referred to as the operation state amount detection value. Set accordingly. The function of the determination reference value stored in advance in the storage unit 30d is a function using, for example, the operating capacity of the compressor 1, the evaporation temperature ET of the refrigerant in the refrigerant circuit, and the condensation temperature CT among the operating state quantities. The refrigerant condensing temperature CT and the evaporation temperature ET are obtained as saturation temperatures of the discharge pressure and the suction pressure. In addition, each operation state quantity here uses the average value of predetermined time (for example, 10 minutes) of the operation state quantity detected in the steady state. A method for setting the determination reference value δm will be described below.

<< Setting method of judgment reference value δm >>
Here, a method for setting the determination reference value δm for determining the deterioration of the compressor 1 in the refrigeration cycle apparatus 100 will be described. The determination reference value δm is a value corresponding to the determination index δ in the initial state in which the compressor 1 has not deteriorated (compressor efficiency has not decreased), and an operation state amount detection value is referred to by referring to a function of the determination reference value. Is set according to The function of the determination reference value is in the form of a function table in which operation state quantities such as the operation capacity of the compressor 1, the refrigerant evaporation temperature ET and the condensation temperature CT in the refrigerant circuit are variables.

  FIG. 5 is a diagram illustrating an example of a function table of the determination reference value δm in the refrigeration cycle apparatus 100. In this example, the common condition is that the outside air temperature Ta = 35 ° C., the evaporator outlet refrigerant superheat degree SH = 2 ° C., the variables are the compressor frequency 78 Hz / 88 Hz / 98 Hz, the condensation temperature CT 38 ° C./42° C./46° C., the evaporation temperature The case where it is each condition of ET0 degreeC / 2 degree / 5 degreeC is shown.

  Using the operating capacity (frequency) of the compressor 1 detected as the operating state quantity and the values of the condensation temperature CT and the evaporation temperature ET, the operation is performed by linear interpolation based on the function table of the determination reference value δm as shown in FIG. A determination reference value δm corresponding to the state quantity is obtained. For example, assuming that the operation state is a compressor frequency of 78 Hz, a condensation temperature CT of 42.5 ° C., and an evaporation temperature of ET 2.2 ° C., the compressor frequency 78 Hz table (δm function table (1)) in FIG. 5 is close to the operation state. Using values of neighboring values δ [122], δ [123], δ [132], δ [133], a value corresponding to the operation state is obtained by linear interpolation, and this value is determined in the operation state. Set as reference value δm.

  Here, the values in the function table of the determination reference value δm, that is, the numerical values stored in δ [111] to δ [333] in FIG. 5 correspond to the operating state by simulation or the like based on the compressor performance characteristics of the target device. A value is obtained in advance, and stored and held in advance as model data in the storage unit 30d.

  The determination reference value δm is set based on the corrected function table of the determination reference value δm by correcting the value of the function table of the determination reference value δm stored and held in advance based on the actual operation data of the target device. May be. For the correction, using the operation data at the initial operation immediately after installation of the target device, the value in the function table of the determination reference value δm is based on the actual operation state when the compressor is normal (when the compressor is not deteriorated). Value. Therefore, it is possible to set a deterioration determination reference value that matches the actual condition of the target device by the correction.

  By obtaining the determination reference value δm using such a method, it is possible to set a suitable deterioration determination reference value according to the operating state and realize a highly accurate compressor deterioration determination.

  In the function table of FIG. 5, specific numerical values are described for each condition of the compressor frequency, the condensation temperature CT, the evaporation temperature ET, the evaporator outlet refrigerant superheat degree SH, and the outside air temperature Ta. It is not limited to what was described, Arbitrary numerical values can be set.

  In addition, here, it has been described that the function of the deterioration determination reference value is stored and held in the function table format, but the function is not limited to this format, and the function formula format with the operating state variable as a variable, and other similar roles. Any other format may be used as long as

  Returning to the flowchart of FIG. After setting the determination reference value δm, the determination unit 30e compares the current determination index δ with the determination threshold value δ0 to determine whether or not the compressor 1 has deteriorated (step S9). Here, the current determination index δ used for determination is an average value of a predetermined time (for example, 10 minutes) of the determination index δ calculated in the steady state. The determination unit 30e determines that the compressor 1 has deteriorated if δ> δ0 (step S9; YES), and outputs an “deterioration of compressor deterioration” signal from the output unit 30g (step S10). The compressor deterioration determination mode is terminated. The determination unit 30e determines that the compressor 1 has not deteriorated if δ ≦ δ0 (step S9; NO), and ends the compressor deterioration determination mode as it is.

  Here, as the determination threshold value δ0, the determination reference value δm may be used as it is, but a value larger than the determination reference value δm by a predetermined value β (for example, 0.5K) is set, that is, δ0 = δm + β [K]. Good. In this way, by setting the determination threshold by taking a certain range from the reference value, the determination index δ is affected by the influence of noise factors other than the compressor deterioration (for example, fluctuation of ambient environment conditions such as outside wind) at the time of compressor deterioration determination. It is possible to avoid misjudgment due to a change in the value.

  Further, in the present embodiment, if it is determined once that the compressor 1 has deteriorated, a signal “abnormal compressor deterioration” is output. For example, the deterioration determination is repeated a plurality of times, and the number of determinations is a predetermined number of times. When the above is reached, a signal indicating “abnormality of compressor deterioration” may be output. By doing so, it is possible to avoid abnormal reporting due to erroneous determination, and to realize highly accurate compressor deterioration determination.

<< Refrigerant state control operation mode >>
FIG. 6 is a flowchart showing the flow of the refrigerant state control operation mode of the refrigeration cycle apparatus 100. Hereinafter, specific operations in the refrigerant state control operation mode will be described based on the flowchart of FIG. In the refrigerant state control operation mode, each actuator operates as follows.

First, the operation state quantity of the refrigerant circuit is detected by the measuring unit 30a (step S21). Subsequently, the control unit 30 calculates the operation capacity change amount of the compressor 1 based on the control target value of the operation capacity of the compressor 1 and the current operation capacity of the compressor 1 (step S22). For example, the operating capacity change amount ΔF of the compressor 1 is obtained from the following equation (1) based on the deviation between the current operating capacity F and the control target value F _m .

ここで、Ｇ_ｆは制御定数であり、例えばＧ_ｆ＝０．１といったように任意の定数を設定する。

Here, G _f is a control constant, and an arbitrary constant is set such as G _f = 0.1, for example.

When the operating capacity change amount ΔF of the compressor 1 is obtained using the above equation (1), if the current operating capacity F <the control target value F _m , ΔF becomes positive and the operation capacity of the compressor 1 is increased. When the current operating capacity F> the control target value F _m , ΔF becomes negative and the operation capacity of the compressor 1 is reduced.

Thereafter, the control unit 30, if the operation capacity F of the compressor 1 is not reached the control target value _{F m} (step S23; NO), the flow returns to step S22. Control unit 30, if the operation capacity F of the compressor 1 has reached the control target value _{F m} (step S23; YES), the process proceeds to the next step.

Next, the control part 30 calculates the rotation speed change amount of the indoor air blower 7a and the indoor air blower 7b based on the control target value of the evaporating temperature ET and the current evaporating temperature ET (step S24). For example, the indoor blower 7a, the rotation speed change amount [Delta] R _i of the indoor blower 7b is obtained from, based on the deviation between the current evaporation temperature ET and the control target value ET _m the following equation (2).

ここで、Ｒ_ｉは現在の室内送風装置回転数である。Ｇ_ｉは制御定数であり、例えばＧ_ｉ＝０．０１といったように任意の定数を設定する。

Here, R _i is the current indoor blower rotation speed. G _i is a control constant, and an arbitrary constant is set, for example, G _i = 0.01.

When the rotational speed change amount ΔR _i of the indoor air blower 7a and the indoor air blower 7b is obtained using the above formula (2), ΔR _i becomes positive when the current evaporation temperature ET <the control target value ET _m , and the indoor air blower. 7a, the operation relates to increasing the rotational speed of the indoor blower 7b, decreasing [Delta] R _i If the current evaporation temperature ET> control target value ET _m is negative and becomes an indoor blower 7a, the rotation speed of the indoor blower 7b operation It becomes.

Thereafter, the control unit 30, does not satisfy a predetermined condition evaporation temperature ET is the control target value ET _m (step S25; NO), the flow returns to step S24. Control unit 30, if they meet a predetermined condition evaporation temperature ET is the control target value ET _m (step S25; YES), the process proceeds to the next step. Here, it is assumed that the predetermined condition is, for example, that the evaporation temperature ET is within the control target value ET _m ± 0.5 ° C.

Next, the control part 30 calculates the rotation speed change amount of the outdoor air blower 6 based on the control target value of the condensation temperature CT and the present condensation temperature CT (step S26). For example, the rotation speed change amount ΔR _o of the outdoor blower 6 is obtained from the following equation (3) based on the deviation between the current condensation temperature CT and the control target value CT _m .

ここで、Ｒ_ｏは現在の室外送風装置回転数である。Ｇ_ｏは制御定数であり、例えばＧ_ｏ＝０．０１といったように任意の定数を設定する。

Here, _Ro is the current outdoor fan rotation speed. G _o is a control constant, and an arbitrary constant is set, for example, G _o = 0.01.

When the rotational speed change amount ΔR _o of the outdoor air blower 6 is obtained using the above formula (3), ΔR _o becomes positive when the current condensation temperature CT> the control target value CT _m , and the rotational speed of the outdoor air blower 6 is determined. When the current condensing temperature CT <the control target value CT _m , ΔR _o becomes negative and the rotation speed of the outdoor blower 6 is decreased.

Thereafter, the control unit 30, does not satisfy a predetermined condition condensation temperature CT is the control target value CT _m (step S27; NO), the flow returns to step S26. Control unit 30, if they meet a predetermined condition condensation temperature CT is the control target value CT _m (step S27; YES), the process proceeds to the next step. Here, it is assumed that the predetermined condition is, for example, that the condensation temperature CT is within the control target value CT _m ± 0.5 ° C.

Next, the control unit 30 calculates the expansion valve 4a, the opening change amount of the expansion valve 4b on the basis of the control target value SH _m the evaporator outlet refrigerant superheat degree SH and the current evaporator outlet refrigerant superheat degree SH (Step S28). For example, the opening change amount ΔL _p of the expansion valve 4a and the expansion valve 4b is obtained from the following equation (4) based on the deviation between the current evaporator outlet refrigerant superheat degree SH and the control target value SH _m .

ここで、Ｌ_ｐは現在の膨張弁開度である。Ｇ_Ｌは制御定数であり、例えばＧ_Ｌ＝０．０１といったように任意の定数を設定する。

Here, L _p is the current expansion valve opening. _GL is a control constant, and an arbitrary constant is set, for example, G _L = 0.01.

When the opening degree change amount ΔL _p of the expansion valve 4a and the expansion valve 4b is obtained using the above equation (4), ΔL _p becomes positive when the current evaporator outlet refrigerant superheat degree SH> the control target value SH _m and the expansion is performed. The operation is to increase the opening degree of the valve 4a and the expansion valve 4b. When the current evaporator outlet refrigerant superheat degree SH <the control target value SH _m , ΔL _p becomes negative and the opening degree of the expansion valve 4a and the expansion valve 4b decreases. It becomes an operation to make.

Thereafter, if the evaporator outlet refrigerant superheat degree SH does not satisfy the predetermined condition with respect to the control target value SH _m (step S29; NO), the control unit 30 returns to step S28. Control unit 30, an evaporator outlet refrigerant superheat degree SH is if they meet a predetermined condition with respect to the control target value SH _m (step S29; YES), it ends the refrigerant state control operation mode. Here, it is assumed that the predetermined condition is, for example, that the evaporator outlet refrigerant superheat degree SH is within the control target value SH _m ± 2.0 ° C.

  As described above, in the refrigeration cycle apparatus 100, the state change amount of each actuator is calculated. By doing so, according to the deviation between the current operating state quantity and the control target value, the control amount can be controlled so that the change amount becomes large if the deviation is large, and the change amount becomes small if the deviation is small. .

  Note that, during the refrigerant state control operation, the timing of performing the actuator state change operation based on the calculated state change amount of each actuator as described above is performed at predetermined time intervals. At this time, the predetermined operation intervals of the actuators may all be the same (for example, 20 seconds). For example, for each actuator, the compressor is 15 seconds, the expansion valve is 20 seconds, and the indoor / outdoor air blower is 60 seconds. In this way, different intervals may be used.

In the present embodiment, the control target value of the evaporator outlet refrigerant superheat degree SH is set as one of the control targets of the operation state quantity for controlling the opening degree of the expansion valve 4a and the expansion valve 4b. Instead of this, a control target value of the compressor suction refrigerant superheat degree SHs may be set. The control target value is set to a larger value so that the refrigerant sucked into the compressor 1 is always in the superheated gas state during the refrigerant state control operation. For example, the control target value SHs _{m of} the compressor suction refrigerant superheat degree SHs is set to 15 ° C. By controlling in this way, the liquid back state in which the liquid refrigerant flows into the compressor suction side can be avoided, and the shell temperature of the compressor 1 can be maintained without being lowered.

Even if the control target value of the intake refrigerant temperature Ts is set instead of the control target value of the evaporator outlet refrigerant superheat degree SH as the control target of the operation state quantity for controlling the opening degree of the expansion valve 4a and the expansion valve 4b. Good. The control target value is set such that, for example, the control target value Ts _m = 10 ° C. of the intake refrigerant temperature Ts. A control target value for the intake refrigerant temperature Ts may be calculated and set based on the control target value for the evaporation temperature ET and the evaporator outlet refrigerant superheat degree SH or the compressor intake refrigerant superheat degree SHs. For example, if the control target value ET _m = 2 ° C. of the evaporation temperature ET and the control target value SHs _m = 8 ° C. of the compressor intake refrigerant superheat degree SHs are set, the control target value Ts _m = ET of the intake refrigerant temperature Ts It can be calculated as _m + SHs _m = 2 ° C. + 8 ° C. = 10 ° C.

Further, the control target value of each actuator is the closest within the range in which the deterioration determination reference value can be set based on the current operation state amount detected by the operation state amount detection means and the variable range in the function of the deterioration determination reference value. Operation conditions may be set. For example, in the present embodiment, the variables of the function of the deterioration determination reference value are set in the range of the compressor frequency 78 to 98 Hz, the condensation temperature CT 38 to 46 ° C., and the evaporation temperature ET 0 to 5 ° C. Assume that the current operating state is a compressor frequency of 60 Hz, a condensation temperature CT = 35.0 ° C., and an evaporation temperature ET 1.5 ° C. Then, the control target value is the control target value F _m = 78 Hz for the operating capacity (frequency) of the compressor, the control target value CT _m = 38 ° C. for the condensation temperature CT, the control target value ET _m = 2 ° C. for the evaporation temperature ET, etc. As described above, it is preferable to set the operating condition within the variable range of the function of the deterioration criterion value and relatively close to the current operating state.

  Setting a control target value that is relatively close to the current operating state in this way reduces the deviation between the control target value of the operating state quantity and the current operating state quantity during the refrigerant state control operation. The amount of change in the actuator state can be reduced.

  In addition, although the control target value of the operation state amount set at the time of the refrigerant state control operation has been described with specific numerical values in the present embodiment, these numerical values are not limited to the contents described, Any numerical value can be set within the technical scope of the present invention.

<< Effects of the refrigeration cycle apparatus 100 >>
The refrigeration cycle apparatus 100 determines the control amount of the actuator during the refrigerant state control operation according to the deviation between the control target value of the operation state amount and the current operation state amount. By doing so, according to the refrigeration cycle apparatus 100, the overshoot phenomenon in which the operating state quantity goes too far with respect to the target refrigerant state, or the state in which the temporal change of the operating state quantity greatly oscillates with respect to the target refrigerant state. The hunting phenomenon can be avoided, and the steady state of the refrigerant circuit can be realized at an early stage and the time required for the compressor deterioration determination can be shortened, that is, the deterioration diagnosis time can be shortened.

  According to the refrigeration cycle apparatus 100, by determining the actuator state so as to be in a predetermined operation state in the compressor deterioration determination operation, and determining the compressor deterioration in the steady state of the refrigerant circuit, ambient environment conditions such as ambient air temperature It is possible to avoid erroneous determination due to fluctuations in the compressor, and to realize highly accurate compressor deterioration determination.

  According to the refrigeration cycle apparatus 100, the control target value of the compressor intake refrigerant superheat degree SHs is set during the refrigerant state control operation, and control is performed so that the compressor intake refrigerant superheat degree SHs becomes equal to or greater than a predetermined value. The liquid back state in which the liquid refrigerant flows into the compressor suction side can be avoided, and the discharge refrigerant temperature Td is not decreased due to the decrease in the shell temperature of the compressor due to the liquid refrigerant flowing into the compressor. Therefore, early stabilization of the refrigerant circuit and shortening of the deterioration diagnosis time can be realized by early stabilization of the discharged refrigerant temperature Td.

  According to the refrigeration cycle apparatus 100, the control target value of the intake refrigerant temperature Ts is set and the compressor intake refrigerant temperature state is controlled during the refrigerant state control operation, so that the refrigerant circuit T Early realization of steady state and shortening of deterioration diagnosis time can be realized.

  According to the refrigeration cycle apparatus 100, the deterioration determination reference value can be set as the control target value of the operation state amount during the refrigerant state control operation based on the current operation state amount and the variable range in the function of the deterioration determination reference value. By setting the operation condition closest to the range, the required amount of change in the actuator state becomes small, so that the steady state of the refrigerant circuit can be realized early and the deterioration diagnosis time can be shortened.

<< Modification of refrigeration cycle apparatus 100 >>
The contents of the present invention have been described in the embodiment. For example, the contents of the refrigerant flow path configuration (piping connection), the configuration of the refrigerant circuit elements such as the compressor, the heat exchanger, and the expansion valve are described in each embodiment. However, the present invention is not limited to the contents described above, and can be appropriately changed within the scope of the technology of the present invention.

  DESCRIPTION OF SYMBOLS 1 Compressor, 2 Four way valve, 3 Outdoor heat exchanger, 4 Expansion valve, 4a Expansion valve, 4b Expansion valve, 5 Indoor heat exchanger, 5a Indoor heat exchanger, 5b Indoor heat exchanger, 6 Outdoor air blower, 7 Indoor blower, 7a Indoor blower, 7b Indoor blower, 11 valve, 11a valve, 11b valve, 30 control unit, 30a measurement unit, 30b calculation unit, 30c drive unit, 30d storage unit, 30e determination unit, 30f input unit , 30 g output unit, 31 discharge pressure sensor, 32 suction pressure sensor, 40 outdoor suction air temperature sensor, 41 discharge temperature sensor, 42 suction temperature sensor, 43 indoor suction air temperature sensor, 43a indoor suction air temperature sensor, 43b indoor suction air Temperature sensor, 44 Gas side temperature sensor, 44a Gas side temperature sensor, 44b Gas side temperature sensor, 45 Liquid side temperature Capacitors, 45a liquid-side temperature sensor, 45b liquid-side temperature sensor, 50 refrigerant piping, 78 compressor frequency, 100 refrigeration cycle apparatus, A outdoor unit, B indoor unit, B1 indoor unit, B2 indoor unit.

Claims (7)

Compressor for compressing refrigerant, condenser for condensing refrigerant compressed by said compressor, decompression device for decompressing refrigerant condensed by said condenser, and evaporator for evaporating refrigerant decompressed by said decompression device A refrigerant circuit configured to circulate refrigerant through a pipe connection;
A condenser blower for blowing air to the condenser;
An evaporator blower for blowing air to the evaporator;
An operation state amount detecting means for detecting an operation state amount of the refrigerant circuit;
A control target value of the operating state amount of the refrigerant circuit for controlling the operating capacity of the compressor, the rotational speed of the condenser air blower, the rotational speed of the evaporator air blower, and the opening of the pressure reducing device is set. , The operating capacity of the compressor, the rotational speed of the condenser blower, the rotational speed of the evaporator blower, and the reduced pressure according to the deviation between the operational state quantity at the control target value and the current operational state quantity A refrigerant state control operation for controlling a refrigerant state of the refrigerant circuit by determining a change amount of the opening degree of the apparatus is performed, and from the refrigerant state of the refrigerant circuit by the refrigerant state control operation and the control target value, the compressor A control unit that determines the operating capacity of the condenser blower, the rotational speed of the evaporator blower, the opening of the decompressor, and
A determination index calculation unit that calculates a determination index used for determining the deterioration of the compressor based on the operation state amount detected by the operation state amount detection unit;
A reference value setting unit for setting a deterioration determination reference value corresponding to the current operation state based on the operation state amount detected by the operation state amount detection means;
When determining the deterioration of the compressor, the control unit determines the operating capacity of the compressor, the rotational speed of the condenser blower, the rotational speed of the evaporator blower, and the opening of the decompressor, When the operation state of the refrigerant circuit is in a steady state, the compressor is deteriorated by comparing the determination index calculated by the determination index calculation unit with the deterioration determination reference value set by the reference value setting unit. A deterioration determination unit that determines whether or not
Equipped with a,
The controller is
A refrigeration cycle apparatus that operates the compressor, the condenser blower, the evaporator blower, and the decompressor at different intervals during the refrigerant state control operation . The controller is
In the refrigerant state control operation,
When the deviation between the control target value and the current operating state amount is large, the change amount is set large,
The refrigeration cycle apparatus according to claim 1, wherein when the deviation between the control target value and the current operating state quantity is small, the change amount is set small. The control target value of the operating state quantity for controlling the opening degree of the decompression device is the suction superheat degree of the compressor,
The controller is
3. The control target value of the intake superheat degree of the compressor is set so that the intake refrigerant of the compressor is in a superheated gas state in the refrigerant state control operation, and the opening degree of the decompression device is controlled. The refrigeration cycle apparatus described in 1. The control target value of the operating state quantity for controlling the opening degree of the decompression device is the intake refrigerant temperature of the compressor,
The controller is
3. The control state value of the intake refrigerant temperature of the compressor is set so that the intake refrigerant temperature of the compressor becomes a predetermined value in the refrigerant state control operation, and the opening degree of the decompression device is controlled. The refrigeration cycle apparatus described in 1. The control target value of the operating state quantity for controlling the operating capacity of the compressor, the rotational speed of the condenser air blower, and the rotational speed of the evaporator air blower is respectively the operating capacity of the compressor and the condensation temperature of the refrigerant. And the evaporation temperature of the refrigerant,
The controller is
A variable range in the function of the current operation state quantity detected by the operation state quantity detection means and the deterioration determination reference value for the operation capacity of the compressor, the condensation temperature of the refrigerant, and the control target value of the evaporation temperature of the refrigerant The refrigeration cycle apparatus according to any one of claims 1 to 4, wherein the deterioration determination reference value is set to a closest condition within a settable range based on the refrigeration cycle. The deterioration determination unit
Of the operating state quantities of the refrigerant circuit, the operating state quantities of the refrigerant condensing temperature, the refrigerant evaporating temperature, the refrigerant superheat degree at the outlet of the evaporator, the discharge refrigerant temperature of the compressor, and the intake refrigerant temperature of the compressor The refrigeration cycle according to any one of claims 1 to 5, wherein a steady state is determined when a deviation between an average value of each operation state amount for a predetermined time and an instantaneous value at the same time is within a predetermined value. apparatus. The deterioration determination unit
An average value of the operation state amount for a predetermined time in a steady state of the refrigerant circuit as a current operation state amount,
An average value for a predetermined time of the determination index calculated based on the operation state quantity in the steady state of the refrigerant circuit is a current determination index,
The current determination index and the deterioration determination reference value calculated by the reference value setting unit based on the current operating state quantity are compared to determine whether or not the compressor has deteriorated. The refrigeration cycle apparatus according to claim 6.

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