JP6887979B2 - Refrigerant leakage determination device, refrigeration device equipped with this refrigerant leakage determination device, and refrigerant leakage determination method - Google Patents

Description

The present disclosure relates to a refrigerant leakage determination device, a refrigerating device including the refrigerant leakage determination device, and a refrigerant leakage determination method.

Conventionally, in an air conditioner in which an outdoor unit having a compressor and an indoor unit are connected by a refrigerant pipe to form a refrigeration cycle, a configuration for determining the presence or absence of refrigerant leakage is known (see, for example, Patent Document 1). ). In such an air conditioner, the outside air temperature at the initial stage of starting the compressor after the installation of the air conditioner, the discharge side temperature of the compressor when the air conditioner is operated under predetermined conditions, and the subsequent compressor. The presence or absence of refrigerant leakage is determined by comparing the outside air temperature at startup with the discharge side temperature of the compressor when the air conditioner is operated under the same predetermined conditions.

Japanese Unexamined Patent Publication No. 2013-204871

In the conventional air conditioner, it is necessary to match the operating conditions of the air conditioner in the initial stage after the installation of the air conditioner and the operating conditions of the air conditioner after that in order to determine the presence or absence of the refrigerant leak, and the refrigerant leaks. It is necessary to perform a special operation to determine the presence or absence of. Therefore, the air conditioner cannot be normally operated during the period for determining the presence or absence of refrigerant leakage. The above problem is not limited to the air conditioner, and similarly occurs in a refrigerating device provided with a refrigerant circuit.

An object of the present disclosure is to provide a refrigerant leakage determination device that does not require a special operation of a refrigerating device for determining the presence or absence of refrigerant leakage, a refrigerating device provided with this refrigerant leakage determination device, and a refrigerant leakage determination method. is there.

The refrigerant leakage determination device that solves this problem has a compressor, a condenser, a decompression device, and an evaporator, and has a refrigerant circuit configured to circulate the refrigerant. A determination device that calculates the degree of deviation of the refrigerant circuit from the normal state based on the data related to the operation of the refrigeration device, and determines the presence or absence of refrigerant leakage based on the calculation results of the calculation unit. Alternatively, it has a determination unit for predicting the timing of refrigerant leakage, and the calculation unit is a first index calculated from the data on the operation of the refrigerating apparatus in the first period among the data on the operation of the refrigerating apparatus. Based on the value and the second index value calculated from the data related to the operation of the refrigerating apparatus in the second period having a length different from that in the first period, the degree of deviation from the normal state of the refrigerant circuit is calculated. The determination unit determines the presence or absence of the refrigerant leakage based on the degree of deviation from the normal state of the refrigerant circuit, or predicts the time when the refrigerant leakage occurs.

According to this configuration, based on the degree of deviation between the first index value and the second index value calculated using the data on the operation of the refrigerating apparatus including the normal operation of the refrigerating apparatus and the operation of the pre-use inspection of the refrigerating apparatus. The degree of deviation from the normal state of the refrigerant circuit can be calculated. This makes it possible to determine the presence or absence of refrigerant leakage or predict the timing of refrigerant leakage occurrence. Data on the operation of the refrigerating apparatus can be obtained by, for example, an operation including a normal operation of the refrigerating apparatus and an operation of a pre-use inspection of the refrigerating apparatus. Therefore, it is possible to determine the presence or absence of refrigerant leakage or predict the timing of refrigerant leakage occurrence without executing a special operation for determining refrigerant leakage.

The refrigerant leakage determination method for solving this problem is a refrigerant leakage determination method for a refrigerating apparatus having a compressor, a condenser, a decompression device, and an evaporator and having a refrigerant circuit configured to circulate the refrigerant. The first index value is calculated from the data storage step for storing the data related to the operation of the refrigerating device and the data related to the operation of the refrigerating device in the first period, and the length of the second period is different from that of the first period. The normality of the refrigerant circuit is based on the first calculation step of calculating the second index value from the data related to the operation of the refrigerating apparatus, the first index value calculated in the first calculation step, and the second index value. A second calculation step for calculating the degree of deviation from the state, a determination step for determining the presence or absence of refrigerant leakage or a determination step for predicting the occurrence time of the refrigerant leakage based on the degree of deviation from the normal state of the refrigerant circuit. Has.

According to this configuration, based on the degree of deviation between the first index value and the second index value calculated using the data on the operation of the refrigerating apparatus including the normal operation of the refrigerating apparatus and the operation of the pre-use inspection of the refrigerating apparatus. The degree of deviation from the normal state of the refrigerant circuit can be calculated. This makes it possible to determine the presence or absence of refrigerant leakage or predict the timing of refrigerant leakage occurrence. Data on the operation of the refrigerating apparatus can be obtained by, for example, an operation including a normal operation of the refrigerating apparatus and an operation of a pre-use inspection of the refrigerating apparatus. Therefore, it is possible to determine the presence or absence of refrigerant leakage or predict the timing of refrigerant leakage occurrence without executing a special operation for determining refrigerant leakage.

The block diagram which conceptually shows the refrigerating apparatus about the refrigerating apparatus of this embodiment. The block diagram which shows the electrical composition of a refrigerating apparatus. The block diagram which shows the electrical structure of the refrigerant leakage determination apparatus of a refrigerating apparatus. (A) is a graph showing an example of the transition of the discharge side refrigerant temperature ratio of the refrigerating apparatus, and (b) is a graph showing an example of the transition of the degree of deviation of the first index value from the second index value. The flowchart which shows an example of the processing procedure of the refrigerant leakage determination processing executed by the refrigerant leakage determination apparatus. The block diagram which conceptually shows the refrigerating apparatus of a modification.

Hereinafter, a transport refrigerating apparatus (hereinafter, simply referred to as “refrigerating apparatus 1”), which is an example of the refrigerating apparatus, will be described with reference to the drawings. The refrigerating device 1 cools the inside of a container such as a marine container or a container for a land transportation trailer. The inside of the casing of the refrigerating apparatus 1 is separated into an internal storage space for circulating the internal air and an external storage space for circulating the external air.

As shown in FIG. 1, the refrigerating apparatus 1 includes a refrigerant circuit 20 in which a compressor 11, a condenser 12, an evaporator 13, and the like are connected by a refrigerant pipe. The refrigerant circuit 20 includes a main circuit 21, a hot gas bypass circuit 22, and a liquid refrigerant bypass circuit 31.

The main circuit 21 is configured by connecting a motor-driven compressor 11, a condenser 12, a first expansion valve 14A, which is an example of a pressure reducing device, and an evaporator 13 in order by a refrigerant pipe.
As shown in FIG. 1, the compressor 11, the condenser 12, the first expansion valve 14A, the outside blower 15 for circulating the outside air to the condenser 12, and the like are housed in the outside storage space. Further, the evaporator 13 and the internal blower 16 and the like that circulate the internal air to the evaporator 13 are housed in the internal storage space.

As the compressor 11, for example, a rotary compressor or a scroll compressor can be used. The compressor 11 is configured such that the rotation speed is controlled by controlling the operating frequency by the inverter, whereby the operating capacity becomes variable.

A fin-and-tube heat exchanger can be used as the condenser 12 and the evaporator 13. The condenser 12 exchanges heat between the outside air supplied by the outside blower 15 and the refrigerant circulating in the condenser 12. The evaporator 13 exchanges heat between the internal air supplied by the internal blower 16 and the refrigerant circulating in the evaporator 13. An example of the outside blower 15 and the inside blower 16 is a propeller fan. A drain pan 28 is provided below the evaporator 13. Frost and ice blocks that have peeled off from the evaporator 13 and condensed dew condensation water that has condensed from the air are collected in the drain pan 28.

As the first expansion valve 14A, for example, an electric expansion valve configured with a variable opening degree by a pulse motor can be used.
The high-pressure gas pipe 23 connecting the compressor 11 and the condenser 12 is provided with a first on-off valve 17A and a check valve 18 in this order in the refrigerant flow direction. As the first on-off valve 17A, for example, an electric expansion valve configured with a variable opening degree by a pulse motor can be used. The check valve 18 allows the flow of the refrigerant in the direction of the arrow shown in FIG.

The high-pressure liquid pipe 24 connecting the condenser 12 and the first expansion valve 14A is provided with a receiver 29, a second on-off valve 17B, a dryer 30, and a supercooling heat exchanger 27 in this order in the direction of refrigerant flow. As the second on-off valve 17B, for example, a solenoid valve that can be opened and closed can be used.

The supercooled heat exchanger 27 has a primary side passage 27a and a secondary side passage 27b that are configured to have a heat exchange relationship with each other. The primary side passage 27a is provided between the dryer 30 and the first expansion valve 14A in the main circuit 21. The secondary side passage 27b is provided in the liquid refrigerant bypass circuit 31. The liquid-refrigerant bypass circuit 31 is a bypass circuit that connects the high-pressure liquid pipe 24 and the intermediate pressure portion (not shown) in the compression mechanism portion in the compressor 11. Between the high-pressure liquid pipe 24 and the secondary side passage 27b in the liquid refrigerant bypass circuit 31, a third on-off valve 17C and a second expansion valve 14B, which is an example of the throttle device, are sequentially arranged in the flow direction of the high-pressure liquid refrigerant. It is connected. With this configuration, the liquid refrigerant flowing from the high-pressure liquid pipe 24 into the liquid refrigerant bypass circuit 31 is expanded to an intermediate pressure by the second expansion valve 14B, and is lower than the liquid refrigerant flowing through the high-pressure liquid pipe 24. It becomes the refrigerant of the above and flows into the secondary side passage 27b. Therefore, the high-pressure liquid refrigerant flowing through the primary side passage 27a is cooled and supercooled by the refrigerant flowing through the secondary side passage 27b. As the third on-off valve 17C, for example, a solenoid valve that can be opened and closed can be used. As the second expansion valve 14B, for example, an electric expansion valve configured with a variable opening degree by a pulse motor can be used.

The hot gas bypass circuit 22 connects the high-pressure gas pipe 23 and the inlet side of the evaporator 13, and bypasses the high-pressure and high-temperature gas refrigerant discharged from the compressor 11 to the inlet side of the evaporator 13. is there. The hot gas bypass circuit 22 has a main passage 32, and a first branch passage 33 and a second branch passage 34 branched from the main passage 32. One end of both the first branch passage 33 and the second branch passage 34 is connected to the main passage 32, and the other end of both is on the inlet side of the evaporator 13, that is, between the first expansion valve 14A and the evaporator 13. It is a parallel circuit connected to the low-voltage connecting pipe 25. A fourth on-off valve 17D is provided in the main passage 32. As the fourth on-off valve 17D, for example, a solenoid valve that can be opened and closed can be used. The first branch passage 33 is composed of only pipes. A drain pan heater 35 is provided in the second branch passage 34. The drain pan heater 35 is provided at the bottom of the drain pan 28 so as to heat the drain pan 28 with a high-temperature refrigerant.

The refrigerating device 1 is provided with various sensors. In one example, as shown in FIGS. 1 and 2, the refrigerating apparatus 1 includes a discharge temperature sensor 41, a discharge pressure sensor 42, a suction temperature sensor 43, a suction pressure sensor 44, a current sensor 45, a rotation sensor 46, and a condensation temperature sensor 47. , And the evaporation temperature sensor 48 is provided. As the sensors 41 to 48, for example, a known sensor can be used.

The discharge temperature sensor 41 and the discharge pressure sensor 42 are provided, for example, in the vicinity of the discharge port of the compressor 11 in the high pressure gas pipe 23. The discharge temperature sensor 41 outputs a signal corresponding to the temperature of the discharge gas refrigerant discharged from the compressor 11. The discharge pressure sensor 42 outputs a signal corresponding to the pressure of the discharge gas refrigerant discharged from the compressor 11. The suction temperature sensor 43 and the suction pressure sensor 44 are provided, for example, in the suction pipe of the compressor 11, that is, in the vicinity of the suction port of the compressor 11 in the low pressure gas pipe 26. The suction temperature sensor 43 outputs a signal corresponding to the temperature of the suction gas refrigerant sucked into the compressor 11. The suction pressure sensor 44 outputs a signal corresponding to the pressure of the suction gas refrigerant sucked into the compressor 11. The current sensor 45 is provided in, for example, an inverter circuit that drives the motor of the compressor 11. The current sensor 45 outputs a signal according to the amount of current flowing through the inverter circuit. The rotation sensor 46 is provided in, for example, the motor of the compressor 11. The rotation sensor 46 outputs a signal according to the rotation speed of the motor.

The condensation temperature sensor 47 is provided in, for example, the condenser 12, and outputs a signal corresponding to the condensation temperature of the refrigerant flowing in the condenser 12. In this embodiment, the condensation temperature sensor 47 is attached to, for example, an intermediate portion of the condenser 12. In this case, the condensation temperature sensor 47 outputs a signal corresponding to the condensation temperature with the refrigerant temperature in the intermediate portion of the condenser 12 as the condensation temperature. The mounting position of the condensation temperature sensor 47 with respect to the condenser 12 can be arbitrarily changed.

The evaporation temperature sensor 48 is provided in, for example, the evaporator 13 and outputs a signal corresponding to the evaporation temperature of the refrigerant flowing in the evaporator 13. In this embodiment, the evaporation temperature sensor 48 is attached to, for example, an intermediate portion of the evaporator 13. In this case, the evaporation temperature sensor 48 outputs a signal corresponding to the evaporation temperature with the refrigerant temperature in the intermediate portion of the evaporator 13 as the evaporation temperature. The mounting position of the evaporation temperature sensor 48 with respect to the evaporator 13 can be arbitrarily changed.

As shown in FIG. 2, the refrigerating device 1 includes a control device 50 for controlling the operation of the refrigerating device 1 and a notification unit 52. A discharge temperature sensor 41, a discharge pressure sensor 42, a suction temperature sensor 43, a suction pressure sensor 44, a current sensor 45, a rotation sensor 46, a condensation temperature sensor 47, and an evaporation temperature sensor 48 are electrically connected to the control device 50, respectively. Has been done. Further, the control device 50 includes a compressor 11, a first expansion valve 14A, a second expansion valve 14B, an outside blower 15, an inside blower 16, a first on-off valve 17A, a second on-off valve 17B, and a third on-off valve 17C. , The fourth on-off valve 17D, and the notification unit 52 are electrically connected. The notification unit 52 notifies the information about the refrigerating device 1 to the outside of the refrigerating device 1. The notification unit 52 has, for example, a display 53 that displays information about the refrigerating device 1. The notification unit 52 may have a speaker in place of or in addition to the display 53. In this case, the notification unit 52 may notify the information about the refrigerating device 1 by voice.

The control device 50 includes a control unit 51. The control unit 51 includes, for example, an arithmetic unit and a storage unit that execute a predetermined control program. The arithmetic processing unit includes, for example, a CPU (Central Processing Unit) or an MPU (Micro Processing Unit). Information used for various control programs and various control processes is stored in the storage unit. The storage unit includes, for example, a non-volatile memory and a volatile memory. The control unit 51 controls the compressor 11, the expansion valves 14A and 14B, the outside blower 15, the inside blower 16, and the on-off valves 17A to 17D based on the detection results of the sensors 41 to 48. The freezing device 1 executes a freezing / cooling operation and a defrosting operation by the control unit 51.

[Freezing / cooling operation]
In the freezing / cooling operation, the first on-off valve 17A, the second on-off valve 17B, and the third on-off valve 17C are in the open state, and the fourth on-off valve 17D is in the closed state. The opening degrees of the first expansion valve 14A and the second expansion valve 14B are appropriately adjusted. Further, the compressor 11, the outside blower 15, and the inside blower 16 are operated.

During the freezing / cooling operation, the refrigerant circulates as shown by the solid arrow in FIG. That is, the high-pressure gas refrigerant compressed by the compressor 11 is condensed by the condenser 12 and then becomes a liquid refrigerant and stored in the receiver 29. The liquid refrigerant stored in the receiver 29 is cooled in the primary side passage 27a of the supercooling heat exchanger 27 via the second on-off valve 17B and the dryer 30, and becomes the supercooled liquid refrigerant as the first expansion valve. It flows to 14A. As shown by the wavy arrow in FIG. 1, a part of the liquid refrigerant flowing out from the receiver 29 becomes an intermediate pressure refrigerant through the third on-off valve 17C and the second expansion valve 14B as a supercooling source and is supercooled. It flows through the secondary side passage 27b of the heat exchanger 27 and cools the liquid refrigerant in the primary side passage 27a. The liquid refrigerant supercooled by the supercooling heat exchanger 27 is decompressed by the first expansion valve 14A and then flows to the evaporator 13. In the evaporator 13, the low-pressure liquid refrigerant absorbs heat from the air inside the refrigerator and is vaporized by evaporation. As a result, the air inside the refrigerator is cooled. The low-pressure gas refrigerant evaporated and vaporized by the evaporator 13 is sucked into the compressor 11 and compressed again.

[Defrost operation]
When the freezing / cooling operation is continuously performed, frost adheres to the surface of the heat transfer tube of the evaporator 13, and the frost gradually grows and enlarges. Therefore, the control unit 51 performs a defrost operation, which is an operation for defrosting the evaporator 13.

The defrost operation is an operation of defrosting the evaporator 13 by bypassing the high-temperature and high-pressure gas refrigerant compressed by the compressor 11 to the inlet side of the evaporator 13, as shown by the broken line arrow in FIG. In the defrost operation, the fourth on-off valve 17D is opened, and the first on-off valve 17A, the second on-off valve 17B, the third on-off valve 17C, and the second expansion valve 14B are fully closed. Then, while the compressor 11 operates, the outside blower 15 and the inside blower 16 are stopped.

The high-pressure, high-temperature gas refrigerant compressed by the compressor 11 flows through the main passage 32, then passes through the fourth on-off valve 17D, and is divided into the first branch passage 33 and the second branch passage 34. The refrigerant diverted into the second branch passage 34 passes through the drain pan heater 35. The refrigerant flowing out of the drain pan heater 35 merges with the refrigerant that has passed through the first branch passage 33 and flows into the evaporator 13. In the evaporator 13, a high-pressure gas refrigerant (so-called hot gas) circulates inside the heat transfer tube. Therefore, in the evaporator 13, the frost adhering to the heat transfer tube and the fins is gradually heated by the high temperature gas refrigerant. As a result, the frost adhering to the evaporator 13 is gradually collected in the drain pan 28. The refrigerant used for defrosting the evaporator 13 is sucked into the compressor 11 and compressed again. Here, inside the drain pan 28, ice blocks and the like that have peeled off from the surface of the evaporator 13 are collected together with the water in which the frost has melted. The ice block or the like is heated by the refrigerant flowing inside the drain pan heater 35 and melts. The melted water is discharged to the outside of the refrigerator through a predetermined flow path.

Further, as shown in FIG. 2, the control device 50 further includes a refrigerant leakage determination device 60 that determines the presence or absence of refrigerant leakage or predicts the timing of refrigerant leakage occurrence. Here, when the refrigerant leaks, an abnormality occurs in the refrigerating apparatus 1 such as a decrease in the compression efficiency of the compressor 11 due to a shortage of the amount of the refrigerant. The refrigerant leakage determination device 60 monitors the temperature of the discharged gas refrigerant discharged from the compressor 11 (hereinafter referred to as “discharge side refrigerant temperature”) to determine the presence or absence of refrigerant leakage, or predicts the time when the refrigerant leakage occurs. To do.

As shown in FIG. 3, the refrigerant leakage determination device 60 includes a data acquisition unit 61, a data storage unit 62, a pretreatment unit 63, a refrigerant leakage determination unit 64, and an output unit 65.
The data acquisition unit 61 is communicably connected to each of the sensors 41 to 48. The data acquisition unit 61 inputs the time series data of each sensor 41 to 48. In one example, each of the sensors 41 to 48 outputs the detection result for each TX for a predetermined time to the refrigerant leakage determination device 60. An example of the predetermined time TX is 1 hour. In one example, each of the sensors 41 to 48 stores the detection results detected by the predetermined sampling cycle over the predetermined time TX, and outputs the averaged detection results in the predetermined time TX to the refrigerant leakage determination device 60. The sensors 41 to 48 may output the detection result detected at a time determined for each TX for a predetermined time to the refrigerant leakage determination device 60.

The data storage unit 62 is electrically connected to the data acquisition unit 61. Data from the data acquisition unit 61 is input to the data storage unit 62. The data storage unit 62 stores the data from the data acquisition unit 61. In one example, the data storage unit 62 sequentially stores the data from the data acquisition unit 61 in chronological order. The data storage unit 62 of the present embodiment is configured as a recording medium built in the refrigerant leakage determination device 60. In this case, the data storage unit 62 may include, for example, a non-volatile memory and a volatile memory. The data storage unit 62 may be a recording medium provided outside the refrigerant leakage determination device 60 or outside the refrigerating device 1. In this case, the data storage unit 62 may include at least one of a USB (Universe Serial Bus) memory, an SD (Secure Digital) memory card, and an HDD (hard disk drive) recording medium.

The preprocessing unit 63 removes data that causes noise in the time-series data for determining the presence or absence of refrigerant leakage or predicting the timing of refrigerant leakage, and supplements the removed data section with alternative data. The pretreatment unit 63 includes a first processing unit 63a and a second processing unit 63b. The data that becomes noise includes, for example, data of instantaneous fluctuations such as immediately after the start of the compressor 11, data of sections that are not continuous over time, and the like.

The first processing unit 63a is electrically connected to the data storage unit 62, and the second processing unit 63b is electrically connected to the first processing unit 63a. The first processing unit 63a extracts a section for supplementing the alternative data. This section is, for example, at least one of a section in which the refrigerating device 1 is stopped, a section immediately after the compressor 11 is started, a section immediately after the compressor 11 is stopped, and a section immediately after the operation of the compressor 11 is switched. including. In the present embodiment, the first processing unit 63a includes a section in which the refrigerating device 1 is stopped, a section immediately after the compressor 11 is started, a section immediately after the compressor 11 is stopped, and immediately after the operation of the compressor 11 is switched. Extract all the sections of.

The second processing unit 63b inputs alternative data to the section extracted by the first processing unit 63a. This alternative data is a value before and after the section extracted by the first processing unit 63a, or a representative value determined in advance. For example, when the first processing unit 63a extracts the section in which the refrigerating device 1 is stopped, the second processing unit 63b substitutes one of the values before and after the section in which the refrigerating device 1 is stopped. And. Here, the data of the section that is stopped, that is, the section that is not continuous with time is regarded as, for example, "0". When the first processing unit 63a extracts the section immediately after the start of the compressor 11, the second processing unit 63b uses the value after the section immediately after the start of the compressor 11 as alternative data. The value after the section immediately after the start of the compressor 11 may be the average value of the data over a predetermined period after the section immediately after the start of the compressor 11, or immediately after the section immediately after the start of the compressor 11. It may be time data. When the first processing unit 63a extracts the section immediately after the operation of the compressor 11 is stopped, the second processing unit 63b uses the value of the section before the section immediately after the operation of the compressor 11 is stopped as alternative data. The value of the section before the section immediately after the operation of the compressor 11 is stopped is the average value of the data in the section immediately before the compressor 11 starts the stop operation as the section before the section immediately after the stop of the compressor 11. It may be the data of the time immediately before the compressor 11 starts the stop operation. When the first processing unit 63a extracts the section immediately after the operation of the compressor 11 is switched, the second processing unit 63b is one of the values of the sections before and after the section immediately after the operation of the compressor 11 is switched. Is the alternative data. One of the values of the sections before and after the section immediately after the operation switching of the compressor 11 is the average value of the data of either one of the sections before and after the section immediately after the switching of the operation of the compressor 11. Alternatively, the data may be data at a predetermined time in any one of the sections before and after the section immediately after the operation of the compressor 11 is switched. As a method of calculating the alternative data, the value calculated by interpolation processing (for example, linear interpolation) of the data before and after the section to be supplemented with the alternative data may be used as the alternative data.

The refrigerant leakage determination unit 64 is electrically connected to the pretreatment unit 63. The refrigerant leakage determination unit 64 determines the presence or absence of refrigerant leakage or predicts the refrigerant leakage occurrence time using the data processed by the pretreatment unit 63. The refrigerant leakage determination unit 64 includes a calculation unit 66 and a determination unit 67.

The calculation unit 66 calculates the first index value and the second index value in order to calculate the degree of deviation of the refrigerant circuit 20 from the normal state. The normal state of the refrigerant circuit 20 means that, for example, the amount of refrigerant (refrigerant filling amount) sealed in the refrigerant circuit 20 is within an appropriate range. The calculation unit 66 calculates the first index value from the data related to the operation of the refrigerating device 1 in the first period among the data related to the operation of the refrigerating device 1. Further, the calculation unit 66 calculates the second index value from the data related to the operation of the refrigerating apparatus 1 in the second period having a length different from that in the first period among the data relating to the operation of the refrigerating apparatus 1. Then, the calculation unit 66 calculates the degree of deviation from the normal state of the refrigerant circuit 20 based on the first index value and the second index value. In the present embodiment, the calculation unit 66 calculates the degree of deviation of the refrigerant circuit 20 from the normal state based on the degree of deviation between the first index value and the second index value. The calculation unit 66 outputs the calculation result to the determination unit 67.

The determination unit 67 determines whether or not there is a refrigerant leak based on the degree of deviation of the refrigerant circuit 20 from the normal state calculated by the calculation unit 66, or predicts the time when the refrigerant leak occurs. The determination unit 67 outputs the determination result or the prediction result to the output unit 65.

Here, the presence or absence of refrigerant leakage means that the amount of refrigerant leakage per unit time is equal to or higher than the first threshold value, not a small amount of refrigerant leakage. An example of the first threshold value is a refrigerant leakage amount that causes an abnormality in the refrigerating apparatus 1 due to a refrigerant leakage, and is determined in advance by a test or the like. An example of an abnormality in the refrigerating apparatus 1 is that the temperature of the compressor 11 becomes excessively high due to the fact that the refrigerant filling amount is less than the lower limit of the appropriate range and the compressor 11 cannot be cooled. Further, the refrigerant leakage occurrence time may be, for example, a time when the refrigerant filling amount is less than the lower limit value of the appropriate range, or the refrigerant filling amount is less than the lower limit value of the appropriate range, and the compressor 11 cannot be cooled. It may be a time when the temperature of the compressor 11 due to the above becomes equal to or higher than the second threshold value. An example of the second threshold value is a temperature at which an abnormality such as seizure of the compression mechanism portion of the compressor 11 is likely to occur, which is predetermined by a test or the like.

The output unit 65 is electrically connected to the data storage unit 62 and the notification unit 52. The output unit 65 outputs the determination result of the presence or absence of the refrigerant leakage or the prediction result of the refrigerant leakage occurrence time to the data storage unit 62 and the notification unit 52. The notification unit 52 displays, for example, the determination result of the presence or absence of refrigerant leakage or the prediction result of the refrigerant leakage occurrence time by the display 53. Further, the output unit 65 has a wireless communication unit including an antenna. The output unit 65 can communicate with the administrator's terminal (administrator's terminal 70) via the wireless communication unit. The output unit 65 outputs the determination result of the presence or absence of the refrigerant leakage or the prediction result of the refrigerant leakage occurrence time to the administrator terminal 70. The administrator terminal 70 may be a portable communication device such as a smartphone or a tablet computer, or may be a desktop personal computer.

Next, the detailed contents of the determination of the presence or absence of the refrigerant leakage performed by the refrigerant leakage determination unit 64 or the prediction of the refrigerant leakage occurrence time will be described.
The calculation unit 66 calculates the first index value by the moving average of the data related to the operation of the refrigerating device 1 in the first period by using the data related to the operation of the refrigerating device 1 accumulated in the data storage unit 62, and calculates the first index value in the second period. The second index value is calculated by the moving average of the data related to the operation of the refrigerating apparatus 1 in the above. The calculation unit 66 calculates the first index value and the second index value using the data of the first period and the second period before the time when the processing is performed. Then, the calculation unit 66 calculates the degree of dissociation between the first index value and the second index value. In the present embodiment, the data of the first period is the data for one day, and the data of the second period is the data for 10 days. Further, in the present embodiment, the sampling cycle is set to 1 hour, and data on the operation of the refrigerating apparatus 1 is acquired every hour. Therefore, the data of the first period and the data of the second period can be indicated not only by the length of the period but also by the number of data, and the data for one day is 24 data, which is for 10 days. The data of is 240 pieces of data.

The first index value and the second index value are the discharge side refrigerant temperature ratios. The discharge-side refrigerant temperature ratio is an example of the discharge-side refrigerant temperature index, and is indicated by the ratio of the predicted value of the discharge-side refrigerant temperature of the compressor 11 to the measured value of the discharge-side refrigerant temperature of the compressor 11. In the present embodiment, the measured value of the discharge side refrigerant temperature of the compressor 11 with respect to the predicted value of the discharge side refrigerant temperature of the compressor 11 is defined as the discharge side refrigerant temperature ratio.

The calculation unit 66 calculates the discharge side refrigerant temperature ratio as data related to the operation of the refrigerating device 1. Specifically, the calculation unit 66 calculates the predicted value of the discharge side refrigerant temperature of the compressor 11 and the measured value of the discharge side refrigerant temperature of the compressor 11, and calculates the discharge side refrigerant temperature of the compressor 11. The discharge side refrigerant temperature ratio is calculated as the ratio of the measured value of the discharge side refrigerant temperature of the compressor 11 to the predicted value.

The calculation unit 66 sets the predicted value of the discharge side refrigerant temperature of the compressor 11 to, for example, the condensation temperature, the evaporation temperature, and the opening degree of the first expansion valve 14A when the amount of refrigerant charged in the refrigerant circuit 20 is within an appropriate range. By regression analysis with at least one of the opening degree of the second expansion valve 14B, the operating frequency of the compressor 11 and the rotation speed of the compressor 11 as variables, the power supply frequency of the power source serving as the power supply source to the refrigerating apparatus 1 And calculated for each power supply voltage.

Specifically, in a transportation refrigeration device such as a marine container, the power frequency and power supply voltage of a power source at a terminal such as a port may differ from the power supply frequency and power supply voltage of a ship's power supply. In one example, the power frequency of the power supply in the terminal is 50 Hz, and the power supply voltage is rated at 380 V ± 10%. The power frequency of the ship's power supply is 60 Hz, and the power supply voltage is rated at 440 V ± 10%. As an example of the combination of the power supply frequency and the power supply voltage, the first to sixth combinations are included. In the first combination, the power supply frequency is 50 Hz and the power supply voltage is 342 V (the lower limit of the power supply voltage when the power supply frequency is 50 Hz). In the second combination, the power supply frequency is 50 Hz and the power supply voltage is 380 V (the median value of the power supply voltage when the power supply frequency is 50 Hz). The third combination has a power supply frequency of 50 Hz and a power supply voltage of 418 V (upper limit value of the power supply voltage when the power supply frequency is 50 Hz). In the fourth combination, the power supply frequency is 60 Hz and the power supply voltage is 396 V (lower limit value of the power supply voltage when the power supply frequency is 60 Hz). In the fifth combination, the power supply frequency is 60 Hz and the power supply voltage is 440 V (the median value of the power supply voltage when the power supply frequency is 60 Hz). In the sixth combination, the power supply frequency is 60 Hz and the power supply voltage is 484 V (the upper limit value of the power supply voltage when the power supply frequency is 60 Hz). The calculation unit 66 calculates the predicted value of the discharge side refrigerant temperature of the compressor 11 for each of the first to sixth combinations. The number of combinations of the power supply frequency and the power supply voltage can be changed arbitrarily.

The calculation unit 66 calculates the measured value of the discharge side refrigerant temperature of the compressor 11 from the signal from the discharge temperature sensor 41. The measured value of the discharge side refrigerant temperature of the compressor 11 becomes higher than the predicted value of the discharge side refrigerant temperature of the compressor 11, for example, as the amount of refrigerant leaked from the refrigerant circuit 20 per unit time increases. Therefore, the degree of deviation of the measured value of the discharge side refrigerant temperature of the compressor 11 from the predicted value of the discharge side refrigerant temperature of the compressor 11 and the amount of refrigerant leakage per unit time have a correlation.

The calculation unit 66 uses the discharge side refrigerant temperature ratio in the first period (hereinafter referred to as "first refrigerant temperature ratio") as the first index value and the discharge side refrigerant temperature ratio in the second period as the second index value (hereinafter referred to as "first"). 2) Calculate the refrigerant temperature ratio). As an example, the graph of FIG. 4A shows the transitions of the first refrigerant temperature ratio and the second refrigerant temperature ratio, respectively. As shown in FIG. 4A, before July 9, the degree of divergence between the first refrigerant temperature ratio and the second refrigerant temperature ratio was small, but after July 9, the degree of divergence gradually increased. You can see that there is.

The calculation unit 66 calculates, for example, the degree of deviation between the first refrigerant temperature ratio and the second refrigerant temperature ratio. In the present embodiment, the degree of deviation between the first refrigerant temperature ratio and the second refrigerant temperature ratio is indicated by the ratio of the first refrigerant temperature ratio to the second refrigerant temperature ratio. As this ratio increases, the degree of deviation between the first refrigerant temperature ratio and the second refrigerant temperature ratio increases. The degree of deviation between the first refrigerant temperature ratio and the second refrigerant temperature ratio may be indicated by the difference between the first refrigerant temperature ratio and the second refrigerant temperature ratio. As this difference increases, the degree of deviation between the first refrigerant temperature ratio and the second refrigerant temperature ratio increases. As an example, the graph of FIG. 4B shows the transition of the degree of deviation between the first refrigerant temperature ratio and the second refrigerant temperature ratio. As shown in FIG. 4B, before July 9, the degree of deviation between the first refrigerant temperature ratio and the second refrigerant temperature ratio is approximately 1.00. It can be seen that after July 9, the degree of divergence between the first refrigerant temperature ratio and the second refrigerant temperature ratio gradually increases.

When the degree of deviation between the first refrigerant temperature ratio and the second refrigerant temperature ratio is equal to or greater than the threshold value XT, the determination unit 67 determines that refrigerant leakage has occurred. The threshold value XT is a value for determining that a refrigerant leak has occurred to the extent that an abnormality occurs in the refrigerating apparatus 1, and is set in advance by a test or the like.

The determination unit 67 predicts the refrigerant leakage occurrence time based on the change tendency of the degree of deviation between the first refrigerant temperature ratio and the second refrigerant temperature ratio. Specifically, the calculation unit 66 calculates, for example, the degree of deviation between the first refrigerant temperature ratio and the second refrigerant temperature ratio every day and outputs it to the determination unit 67. The determination unit 67 acquires, for example, the change tendency of the degree of deviation from the degree of deviation between the first refrigerant temperature ratio and the second refrigerant temperature ratio every day. The determination unit 67 predicts the refrigerant leakage occurrence time based on the degree of deviation tending to increase and the slope of the degree of deviation. More specifically, the determination unit 67 predicts the time when the degree of deviation reaches the threshold value XT based on the slope of the degree of deviation between the first refrigerant temperature ratio and the second refrigerant temperature ratio. The determination unit 67 may calculate the slope of the degree of dissociation by, for example, regression analysis, or may calculate it from a straight line connecting the degree of dissociation between two predetermined periods. In one example, as shown in FIG. 4B, the determination unit 67 determines after July 16 based on the transition of the degree of deviation between the first refrigerant temperature ratio and the second refrigerant temperature ratio up to July 16. Predict the degree of divergence (broken line portion in FIG. 4B). The determination unit 67 predicts the refrigerant leakage occurrence time based on the transition of the degree of dissociation after July 16 and the comparison with the threshold value XT.

With reference to FIG. 5, a specific processing procedure for determining the presence or absence of refrigerant leakage by the refrigerant leakage determination device 60 or predicting the occurrence time of refrigerant leakage will be described. This process is performed, for example, when the user requests, when the power of the refrigerating device 1 or the refrigerant leakage determining device 60 is turned on, when the transportation of the refrigerating device 1 is completed, and before the refrigerating device 1 is used. Performed in at least one case when the inspection was performed. In the present embodiment, the refrigerant leakage determination device 60 is used when the user requests, when the power of the refrigerating device 1 or the refrigerant leakage determining device 60 is turned on, when the transportation of the refrigerating device 1 is completed, and In each case when the pre-use inspection of the refrigerating device 1 is carried out, the presence or absence of refrigerant leakage or the prediction of the refrigerant leakage occurrence time is executed.

The refrigerant leakage determination device 60 calculates the first refrigerant temperature ratio and the second refrigerant temperature ratio from the data related to the operation of the refrigerating device 1 in step S11, respectively, and proceeds to step S12. The refrigerant leakage determination device 60 calculates the degree of deviation between the first refrigerant temperature ratio and the second refrigerant temperature ratio in step S12, and proceeds to step S13.

In step S13, the refrigerant leakage determination device 60 determines whether or not the degree of deviation between the first refrigerant temperature ratio and the second refrigerant temperature ratio is equal to or greater than the threshold value XT. If the refrigerant leakage determination device 60 makes an affirmative determination in step S13, it determines that a refrigerant leakage has occurred in step S14, and proceeds to step S15. In step S15, the refrigerant leakage determination device 60 communicates the determination result with at least one of the display 53 and the administrator terminal 70, and temporarily ends the process. The display 53 and the administrator terminal 70 complete the transportation of the refrigerating device 1 when the power of the refrigerating device 1 or the refrigerant leakage determining device 60 is turned on when the user requests in step S15. The result of determining the presence or absence of refrigerant leakage or the prediction result of the time when the refrigerant leak occurs is notified at least in one case when the refrigerating device 1 is inspected before use. In the present embodiment, the display 53 and the administrator terminal 70 complete the transportation of the refrigerating device 1 when the refrigerating device 1 or the refrigerant leakage determining device 60 is turned on at the request of the user. In each case, and when the pre-use inspection of the refrigerating device 1 is carried out, the determination result of the presence or absence of the refrigerant leakage or the prediction result of the refrigerant leakage occurrence time is notified. In step S15, the notification unit 52 may be communicated instead of the display 53. When the notification unit 52 has a speaker, the notification unit 52 may notify the determination result of the presence or absence of refrigerant leakage or the prediction result of the refrigerant leakage occurrence time by the speaker.

When the refrigerant leakage determination device 60 makes a negative determination in step S13, the refrigerant leakage determination device 60 calculates the change tendency of the degree of deviation between the first refrigerant temperature ratio and the second refrigerant temperature ratio in step S16, and proceeds to step S17.

The refrigerant leakage determination device 60 predicts the refrigerant leakage occurrence time based on the slope of the change in the degree of deviation between the first refrigerant temperature ratio and the second refrigerant temperature ratio in step S17, and proceeds to step S18. In step S18, the refrigerant leakage determination device 60 communicates the prediction result with at least one of the display 53 and the administrator terminal 70, and temporarily ends the process. As described above, in the flowchart shown in FIG. 5, the refrigerant leakage determination device 60 determines the presence or absence of the refrigerant leakage and then predicts the time when the refrigerant leakage occurs.

The refrigerant leakage determination method in the refrigerant leakage determination device 60 described above includes a data storage step, a first calculation step, a second calculation step, and a determination step. This will be described below.

The data storage step is a step of storing data related to the operation of the refrigerating apparatus 1. In one example, in the data storage step, the data from the data acquisition unit 61 regarding the operation of the refrigerating device 1 is stored in the data storage unit 62 as time series data.

The first calculation step is a step of calculating the first index value from the data related to the operation of the refrigerating apparatus 1 in the first period and calculating the second index value from the data relating to the operation of the refrigerating apparatus 1 in the second period. In one example, the first calculation step is executed by the calculation unit 66, the first index value is calculated by the moving average of the data related to the operation of the refrigerating apparatus 1 in the first period, and the refrigerating apparatus in the second period. The second index value is calculated by the moving average of the data related to the operation of 1. Further, in one example, the first calculation step includes a pretreatment step in which data that becomes noise for determining the presence or absence of refrigerant leakage or predicting the occurrence time of refrigerant leakage is deleted by the preprocessing unit 63 and supplemented with alternative data. .. Regarding the relationship between the first calculation step and FIG. 5, step S11 in FIG. 5 corresponds to the first calculation step.

The second calculation step is a step of calculating the degree of deviation from the normal state of the refrigerant circuit 20 from the first index value and the second index value. In one example, the second calculation step is performed by the calculation unit 66. Regarding the relationship between the second calculation step and FIG. 5, step S12 in FIG. 5 corresponds to the second calculation step.

The determination step is a step of determining the presence or absence of refrigerant leakage or predicting the timing of refrigerant leakage occurrence based on the degree of deviation of the refrigerant circuit 20 from the normal state. In one example, the second index value is set to the normal state of the refrigerant circuit 20, and when the degree of deviation of the first index value from the second index value is equal to or greater than a certain threshold value, it is determined that refrigerant leakage has occurred. The determination step predicts the time when the refrigerant leak occurs by predicting when the degree of deviation reaches the threshold value based on the tendency of the degree of deviation of the first index value with respect to the second index value. Regarding the relationship between the determination step and FIG. 5, steps S13 to S18 in FIG. 5 correspond to the determination step.

Next, the operation of this embodiment will be described.
The refrigerant leakage determination device 60 calculates a second index value from the data related to the operation of the refrigerating device 1 in the second period by a moving average, and uses the calculated second index value as a reference. In the present embodiment, since the second period is data relating to the operation of the refrigerating apparatus 1 over a long period of 10 to 30 days, the influence of fluctuations relating to the operation of the refrigerating apparatus 1 during a short period such as 1 day is reduced.

Further, the refrigerant leakage determination device 60 calculates the first index value by the moving average from the data related to the operation of the refrigerating device 1 in the first period. In the present embodiment, since the first period is data on the operation of the freezing device 1 in a short period of one day, the influence of recent fluctuations on the operation of the freezing device 1 is large.

In this way, how much the first index value, which is largely affected by the fluctuation in the operation of the refrigerating apparatus 1, deviates from the second index value, is based on the second index value, which is less affected by the recent fluctuation in the operation of the refrigerating apparatus 1. By monitoring this, it becomes easy to extract fluctuations related to the operation of the freezing device 1. As a result, when a refrigerant leak occurs, the first index value deviates significantly from the second index value, so that the refrigerant leak determination device 60 can determine that the refrigerant leak has occurred. Further, the refrigerant leakage determination device 60 can predict the time when the refrigerant leak occurs by acquiring the change tendency of the degree of deviation of the first index value with respect to the second index value and predicting the transition of the degree of deviation.

According to this embodiment, the following effects can be obtained.
(1) In the calculation unit 66, among the data related to the operation of the refrigerating device 1, the first index value calculated from the data related to the operation of the refrigerating device 1 in the first period and the second index value having a different length from the first period The deviation state from the normal state of the refrigerant circuit 20 is calculated based on the second index value calculated from the data related to the operation of the refrigerating apparatus 1 during the period. The determination unit 67 determines the presence or absence of refrigerant leakage based on the degree of deviation of the refrigerant circuit 20 from the normal state, or predicts the timing of refrigerant leakage occurrence. According to this configuration, the first index value calculated using the data related to the operation of the refrigerating device 1 including the normal operation such as the cooling operation and the defrosting operation of the refrigerating device 1 and the operation of the pre-use inspection of the refrigerating device 1. The deviation state from the normal state of the refrigerant circuit 20 can be calculated based on the deviation state from the second index value. As a result, it is possible to determine the presence or absence of refrigerant leakage or predict the timing of refrigerant leakage occurrence based on the deviation state of the refrigerant circuit 20 from the normal state. In this way, it is possible to determine the presence or absence of refrigerant leakage or predict the timing of refrigerant leakage occurrence without executing a special operation for determining the presence or absence of refrigerant leakage.

(2) The second index value calculated from the second period with a long period has little influence on the fluctuation of the operation of the freezing device 1, and the first index value calculated from the first period with a short period is the refrigerating device 1. The impact on driving fluctuations will increase. Therefore, in the present embodiment, the calculation unit 66 calculates the degree of deviation from the normal state of the refrigerant circuit 20 based on the degree of deviation between the first index value and the second index value. This makes it easier to extract fluctuations in the operation of the refrigerating device 1, and can determine the presence or absence of refrigerant leakage or predict the timing of refrigerant leakage based on the fluctuations in the operation of the refrigerating device 1.

(3) The first index value is calculated by the moving average of the data related to the operation of the freezing device 1 in the first period, and the second index value is calculated by the moving average of the data related to the operation of the refrigerating device 1 in the second period. To. According to this configuration, the presence or absence of refrigerant leakage or the prediction of the occurrence time of refrigerant leakage is determined based on the degree of dissociation between the fluctuation of the operation of the refrigerating device 1 over a long period of time and the fluctuation of the operation of the refrigerating device 1 over a short period of time. It can be performed.

(4) When the amount of refrigerant (refrigerant filling amount) enclosed in the refrigerant circuit 20 is less than the appropriate range, the suction pressure of the compressor 11 decreases, resulting in insufficient cooling by the refrigerant inside the compressor 11. The temperature of the compressor 11 may become excessively high. That is, the discharge side refrigerant temperature of the compressor 11 when the amount of refrigerant sealed in the refrigerant circuit 20 is less than the lower limit of the appropriate range is the temperature of the compressor 11 when the amount of refrigerant sealed in the refrigerant circuit 20 is within the appropriate range. It becomes higher than the discharge side refrigerant temperature. Therefore, in the present embodiment, as the first index value and the second index value, the discharge side refrigerant temperature ratio, which is the measured value of the discharge side refrigerant temperature with respect to the predicted value of the discharge side refrigerant temperature of the compressor 11, is used. Therefore, it is possible to accurately determine the presence or absence of refrigerant leakage or predict the timing of refrigerant leakage occurrence.

(5) The calculation unit 66 calculates the predicted refrigerant temperature for each power frequency and power supply voltage, and calculates the first refrigerant temperature ratio and the second refrigerant temperature ratio for each power supply frequency and power supply voltage. As a result, the first refrigerant temperature ratio and the second refrigerant temperature ratio can be calculated more accurately, so that the presence or absence of refrigerant leakage or the prediction of the refrigerant leakage occurrence time can be accurately performed.

(6) Refrigerant leakage is performed by omitting data related to the operation of the refrigerating apparatus 1 that causes noise when the pretreatment unit 63 determines the presence or absence of refrigerant leakage or predicts the timing of refrigerant leakage occurrence, and supplementing with alternative data. It is possible to accurately determine the presence or absence of the refrigerant or predict the time when the refrigerant leak occurs.

(7) When the first processing unit 63a extracts the section immediately after the start of the compressor 11, the second processing unit 63b uses the value after the section immediately after the start of the compressor 11 as substitute data. When the first processing unit 63a extracts the section immediately after the operation of the compressor 11 is stopped, the second processing unit 63b uses the value of the section before the section immediately after the operation of the compressor 11 is stopped as alternative data. When the first processing unit 63a extracts the section immediately after the operation of the compressor 11 is switched, the second processing unit 63b is one of the values of the sections before and after the section immediately after the operation of the compressor 11 is switched. Is the alternative data. According to this configuration, the degree of divergence between the data related to the actual operation of the refrigerating apparatus 1 and the alternative data can be reduced by using the data that is close in time to the section extracted by the first processing unit 63a as the alternative data. Therefore, it is possible to accurately determine the presence or absence of refrigerant leakage or predict the timing of refrigerant leakage occurrence.

(8) Since the notification unit 52 displays the occurrence of the refrigerant leakage or the time when the refrigerant leakage occurs on the display 53 of the refrigerating device 1 or the terminal 70 for the administrator, the administrator or the operator of the refrigerating device 1 causes the refrigerant leakage. It is possible to grasp the time of occurrence or refrigerant leakage.

(Change example)
The description of the above embodiment is an example of a form in which the refrigerant leakage determination device according to the present disclosure, the refrigerating device provided with the refrigerant leakage determination device, and the refrigerant leakage determination method can be taken, and is not intended to limit the form. .. The refrigerant leakage determination device according to the present disclosure, the refrigerating device provided with the refrigerant leakage determination device, and the refrigerant leakage determination method are, for example, a combination of the modification of the above embodiment shown below and at least two modifications that do not contradict each other. Can take the form. In the following modification examples, the parts common to the above-described embodiment are designated by the same reference numerals as those in the above-described embodiment, and the description thereof will be omitted.

-In the above embodiment, the degree of deviation between the first index value and the second index value is shown as the ratio of the first index value to the second index value, but the present invention is not limited to this. The method of calculating the degree of dissociation between the first index value and the second index value can be arbitrarily changed. In one example, the calculation unit 66 determines the degree of dissociation between the first index value and the second index value as the standard deviation, skewness, likelihood, kurtosis, and average value using the first index value and the second index value. It may be calculated based on at least one of.

-In the above embodiment, the refrigerant leakage determination device 60 executes both the determination of the presence or absence of the refrigerant leakage and the prediction of the refrigerant leakage occurrence time, but is not limited to this. The refrigerant leakage determination device 60 may only determine the presence or absence of refrigerant leakage. Further, the refrigerant leakage determination device 60 may execute the prediction of the refrigerant leakage occurrence time when the degree of deviation between the first index value and the second index value is smaller than the threshold value XT. In this case, the refrigerant leakage determination device 60 can omit the determination of the presence or absence of refrigerant leakage.

-In the above embodiment, the pretreatment unit 63 removes data that becomes noise for determining the presence or absence of refrigerant leakage or predicting the occurrence time of refrigerant leakage in the time series data, and substitutes the section of the removed data. It was supplemented with data, but it is not limited to this. The pretreatment unit 63 may only remove data that becomes noise for determining the presence or absence of refrigerant leakage or predicting the timing of refrigerant leakage in the time series data. According to this configuration, it is possible to accurately determine the presence or absence of refrigerant leakage or predict the timing of refrigerant leakage occurrence.

-In the above embodiment, instead of the discharge side refrigerant temperature ratio, the first index value and the second index value may be calculated from the predicted value of the discharge side refrigerant temperature or the measured value of the discharge side refrigerant temperature. In one example, the calculation unit 66 calculates the first index value by the moving average of the predicted value of the discharge side refrigerant temperature in the first period, and the second index value by the moving average of the predicted value of the discharge side refrigerant temperature in the second period. Is calculated. Further, in one example, the calculation unit 66 calculates the first index value by the moving average of the measured values of the discharge side refrigerant temperature in the first period, and the second index by the moving average of the measured values of the discharge side refrigerant temperature in the second period. Calculate the value.

-In the above embodiment, instead of the discharge side refrigerant temperature ratio as the first index value and the second index value, the measured value of the refrigerant pressure on the discharge side of the compressor 11 with respect to the predicted value of the refrigerant pressure on the discharge side of the compressor 11. The discharge side refrigerant pressure ratio, which is the ratio of The calculation unit 66 uses the discharge side refrigerant pressure ratio in the first period (hereinafter referred to as "first refrigerant pressure ratio") as the first index value and the discharge side refrigerant pressure ratio in the second period as the second index value (hereinafter referred to as "first"). 2) Calculate the refrigerant pressure ratio). Then, the calculation unit 66 calculates the degree of deviation between the first refrigerant pressure ratio and the second refrigerant pressure ratio. When the degree of deviation between the first refrigerant pressure ratio and the second refrigerant pressure ratio is equal to or greater than a predetermined threshold value, the determination unit 67 determines that refrigerant leakage has occurred. Further, the determination unit 67 predicts the refrigerant leakage occurrence time based on the change tendency of the degree of deviation between the first refrigerant pressure ratio and the second refrigerant pressure ratio. Further, instead of the discharge side cooling temperature ratio, the ratio of the measured value of the superheat degree of the intake gas refrigerant to the predicted value of the superheat degree of the intake gas refrigerant sucked into the compressor 11 may be used, or the ratio of the measured value of the superheat degree of the suction gas refrigerant may be used. The ratio of the measured value of the supercooling degree of the liquid refrigerant at the outlet of the condenser 12 to the predicted value of the supercooling degree of the liquid refrigerant at the outlet may be used.

-In the above modification, instead of the discharge side refrigerant pressure ratio, the first index value and the second index value are obtained from the predicted value of the refrigerant pressure on the discharge side of the compressor 11 or the measured value of the refrigerant pressure on the discharge side of the compressor 11. May be calculated. In one example, the calculation unit 66 calculates the first index value by the moving average of the predicted values of the refrigerant pressure on the discharge side of the compressor 11 in the first period, and calculates the refrigerant pressure on the discharge side of the compressor 11 in the second period. The second index value is calculated by the moving average of the predicted values. Further, in one example, the calculation unit 66 calculates the first index value by the moving average of the measured values of the refrigerant pressure on the discharge side of the compressor 11 in the first period, and calculates the refrigerant pressure on the discharge side of the compressor 11 in the second period. The second index value is calculated by the moving average of the measured values of.

-In the above embodiment, the data storage unit 62 may be an external server of the refrigerating device 1 communicatively connected to the refrigerating device 1. An example of this server includes a cloud server. That is, the refrigerant leakage determination device 60 stores the data on the server by transmitting the data acquired by the data acquisition unit 61 to the server.

In the above embodiment, the refrigerant leakage determination device 60 and the notification unit 52 are separately provided, but the present invention is not limited to this, and the refrigerant leakage determination device 60 may have the notification unit 52.
-In the above embodiment, the configuration of the transport refrigerating device has been described as the refrigerating device 1, but the configuration of the refrigerating device is not limited to this. For example, it may be applied to a refrigerating device for a stationary warehouse. When the refrigerating device 1 is applied to a refrigerating device other than the refrigerating device for transportation, the refrigerant leakage determining device 60 turns on the power of the refrigerating device 1 or the refrigerant leak determining device 60 at the request of the user. When, and at least one case when the pre-use inspection of the refrigerating apparatus 1 is performed, the presence or absence of refrigerant leakage is determined, or the timing of refrigerant leakage occurrence is predicted. Further, the notification unit 52 is at least one when the refrigerating device 1 or the refrigerant leakage determining device 60 is turned on when requested by the user, and when the pre-use inspection of the refrigerating device 1 is performed. In this case, the determination result of the presence or absence of the refrigerant leakage or the prediction result of the refrigerant leakage occurrence time is notified.

-In the above embodiment, the configuration of the refrigerating apparatus 1 for the container has been described, but the configuration of the refrigerating apparatus is not limited to this. For example, as shown in FIG. 6, the refrigerating device may be used as an air conditioner 80. The air conditioner 80 includes a refrigerant circuit 90 formed by connecting an outdoor unit 80A installed outdoors and a wall-mounted indoor unit 80B attached to an indoor wall surface or the like by a refrigerant pipe 91.

The outdoor unit 80A includes a compressor 81 whose capacity is variable by changing the operating frequency, a four-way switching valve 82, an outdoor heat exchanger 83, an expansion valve 84, an outdoor fan 85, an outdoor control device 86, and the like. The compressor 81 is, for example, a swing piston type compressor, and includes a compression mechanism, a motor, a crankshaft that transmits the driving force of the motor to the compression mechanism, and the like. The outdoor heat exchanger 83 exchanges heat between the outside air and the refrigerant, and for example, a fin and tube heat exchanger can be used. The expansion valve 84 is, for example, an electronic expansion valve. The outdoor fan 85 has a motor whose rotation speed can be changed as a drive source, and an impeller connected to the output shaft of the motor. An example of an impeller is a propeller fan. The outdoor fan 85 generates an air flow of outdoor air passing through the outdoor heat exchanger 83 by rotating the impeller by a motor. The outdoor control device 86 is electrically connected to the motor of the compressor 81, the four-way switching valve 82, the expansion valve 84, and the motor of the outdoor fan 85, and controls their operations.

The indoor unit 80B includes an indoor heat exchanger 87, an indoor fan 88, an indoor control device 89, and the like. The indoor heat exchanger 87 exchanges heat between the indoor air and the refrigerant, and for example, a fin and tube heat exchanger can be used. The indoor fan 88 has a motor whose rotation speed can be changed as a drive source, and an impeller connected to the output shaft of the motor. An example of an impeller is a cross-flow fan. The indoor control device 89 is electrically connected to the indoor fan 88 and controls the operation of the indoor fan 88.

The refrigerant circuit 90 is formed by connecting the compressor 81, the four-way switching valve 82, the outdoor heat exchanger 83, and the expansion valve 84, the indoor heat exchanger 87, and the accumulator 81a in an annular shape by the refrigerant pipe 91. By switching the four-way switching valve 82, a steam compression refrigeration cycle in which the refrigerant is reversibly circulated can be executed.

That is, when the four-way switching valve 82 is switched to the cooling mode connection state (state shown in the solid line in the figure), the refrigerant circuit 90 has the compressor 81, the four-way switching valve 82, the outdoor heat exchanger 83, the expansion valve 84, and the indoor. A cooling cycle is formed in which the refrigerant circulates in the order of the heat exchanger 87, the four-way switching valve 82, the accumulator 81a, and the compressor 81. As a result, in the air conditioner 80, the cooling operation is performed in which the outdoor heat exchanger 83 acts as a condenser and the indoor heat exchanger 87 acts as an evaporator. Further, by switching the four-way switching valve 82 to the heating mode connection state (state shown by the broken line in the figure), the refrigerant circuit 90 includes the accumulator 81a, the compressor 81, the four-way switching valve 82, the indoor heat exchanger 87, and the expansion valve. A heating cycle is formed in which the refrigerant circulates in the order of 84, the outdoor heat exchanger 83, the four-way switching valve 82, and the compressor 81. As a result, in the air conditioner 80, the heating operation is performed in which the indoor heat exchanger 87 acts as a condenser and the outdoor heat exchanger 83 acts as an evaporator.

In the air conditioner 80, for example, the refrigerant leakage determination device 60 (not shown in FIG. 6) is provided in either the outdoor control device 86 or the indoor control device 89. The notification unit 52 (not shown in FIG. 6) is provided, for example, on the remote controller of the air conditioner 80.

-In the above embodiment, the refrigerating device 1 is provided with the refrigerant leakage determination device 60, but the configuration of the refrigerating device 1 is not limited to this. For example, the refrigerant leakage determination device 60 may be omitted from the refrigerating device 1. The refrigerant leakage determination device 60 may be provided separately from the refrigerating device 1. In one example, the refrigerant leakage determination device 60 may be provided on a server capable of communicating with the refrigerating device 1. In this case, the refrigerating device 1 acquires the determination result of the presence or absence of the refrigerant leakage or the prediction result of the refrigerant leakage occurrence time by communicating with the refrigerant leakage determination device 60.

Although the embodiments of this device have been described above, it is understood that various changes in form and details are possible without departing from the purpose and scope of the device described in the claims. Let's go.

1 ... Refrigeration equipment (transportation refrigeration equipment)
11 ... Compressor 12 ... Condenser 13 ... Evaporator 14A ... First expansion valve (pressure reducing device)
14B ... Second expansion valve (pressure reducing device)
20 ... Refrigerant circuit 52 ... Notification unit 60 ... Refrigerant leakage determination device 66 ... Calculation unit 67 ... Judgment unit

Claims (11)

A refrigerating device (1) having a compressor (11), a condenser (12), a depressurizing device (14A, 14B), and an evaporator (13), and including a refrigerant circuit (20) configured to circulate the refrigerant. ), Which is a refrigerant leakage determination device (60) for determining the refrigerant leakage.
The refrigerant leakage determination device (60) includes a calculation unit (66) that calculates an index value based on data related to the operation of the refrigeration device (1), and a refrigerant leakage occurrence based on the calculation result of the calculation unit (66). It has a determination unit (67) that predicts the time, and
The calculation unit (66) calculates from the data related to the operation of the refrigerating device (1) in the first period prior to the time when the calculation of the index value is performed among the data related to the operation of the refrigerating device (1). Calculated from the first index value to be calculated and the data related to the operation of the refrigerating apparatus (1) in the second period, which is longer than the length of the first period and before the time when the calculation of the index value is performed. The degree of deviation of the first index value from the second index value is calculated based on the second index value to be obtained.
The determination unit (67) calculates the change tendency of the degree of divergence in time series, and the refrigerant leakage occurs based on the tendency of change of the degree of divergence of the first index value with respect to the second index value in time series. It predicts the time
Each of the first index value and the second index value is a discharge side refrigerant temperature ratio or a discharge side refrigerant pressure ratio.
The discharge-side refrigerant temperature ratio is a value defined by the ratio of the predicted value of the discharge-side refrigerant temperature of the compressor (11) to the measured value of the discharge-side refrigerant temperature of the compressor (11).
The discharge-side refrigerant pressure ratio is a value defined by the ratio of the predicted value of the discharge-side refrigerant pressure of the compressor (11) to the measured value of the discharge-side refrigerant pressure of the compressor (11). ,
The predicted values of the discharge side refrigerant temperature of the compressor (11) are the condensation temperature and the evaporation temperature when the amount of refrigerant charged in the refrigerant circuit (20) is within an appropriate range, and the expansion valve (14A) which is the decompression device. , 14B), the operating frequency of the compressor (11), and the rotation speed of the compressor (11) are used as variables for regression analysis to supply power to the refrigerating apparatus (1). Calculated for each power frequency and power voltage of the source power supply
The predicted values of the refrigerant pressure on the discharge side of the compressor (11) are the condensation pressure and evaporation pressure when the amount of refrigerant charged in the refrigerant circuit (20) is within an appropriate range, and the expansion valve (expansion valve) which is the decompression device. By regression analysis with at least one of the opening degree of 14A, 14B), the operating frequency of the compressor (11), and the rotation speed of the compressor (11) as variables, the power to the refrigerating apparatus (1) is supplied. Calculated for each power supply frequency and power supply voltage of the power supply source
The data relating to the operation of the refrigerating apparatus (1) in the first period is the data for the most recent day at the time point.
The data relating to the operation of the refrigerating apparatus (1) in the second period is the data for the latest 10 days or more and 30 days or less at the time point. The data relating to the operation of the refrigerating apparatus (1) in the first period is 24 data.
The refrigerant leakage determination device according to claim 1, wherein the data relating to the operation of the refrigerating device (1) in the second period is 240 or more and 720 or less. The first index value is calculated by a moving average of data relating to the operation of the refrigerating apparatus (1) during the first period.
The refrigerant leakage determination device according to claim 1 or 2, wherein the second index value is calculated by a moving average of data relating to the operation of the refrigerating device (1) in the second period. The calculation unit (66) includes data on the section where the refrigerating device (1) is stopped, data on the section immediately after the compressor (11) is started, and data on the section immediately after the compressor (11) is stopped. , And the first index value and the second index value are calculated by excluding at least one of the data of the section immediately after the operation of the compressor (11) is switched.
The refrigerant leakage determination device according to any one of claims 1 to 3. The calculation unit (66) includes data on the section where the refrigerating device (1) is stopped, data on the section immediately after the compressor (11) is started, and data on the section immediately after the compressor (11) is stopped. , And the first index value and the second index value are calculated using alternative data for at least one of the data in the section immediately after the operation of the compressor (11) is switched.
The refrigerant leakage determination device according to any one of claims 1 to 3. The alternative data includes a section in which the refrigerating apparatus (1) is stopped, a section immediately after the compressor (11) is started, a section immediately after the compressor (11) is stopped, and the compressor (11). It is a value before and after the section using the alternative data in the section immediately after the operation switching, or a predetermined representative value.
The refrigerant leakage determination device according to claim 5. The calculation unit (66) determines the degree of deviation of the first index value from the second index value by using the standard deviation, skewness, likelihood, kurtosis, etc. using the first index value and the second index value. And calculated based on at least one of the mean values
The refrigerant leakage determination device according to any one of claims 1 to 6. Further, it has a notification unit (52) for notifying the determination result of the presence or absence of the refrigerant leakage or the prediction result of the refrigerant leakage occurrence time.
When the user requests, the notification unit (52) turns on the power of the refrigerating device (1) or the refrigerant leakage determining device (60), and uses the refrigerating device (1). Notify the determination result of the presence or absence of the refrigerant leakage or the prediction result of the refrigerant leakage occurrence time in at least one case when the pre-inspection is performed.
The refrigerant leakage determination device according to any one of claims 1 to 7. A refrigerating device including the refrigerant leakage determination device (60) according to any one of claims 1 to 8. The refrigerating device includes a transport refrigerating device (1).
The transport refrigerating device (1) further includes a notification unit (52) for notifying the determination result of the presence or absence of the refrigerant leakage or the prediction result of the refrigerant leakage occurrence time.
The notification unit (52) has the transport refrigerating device (1) when the power of the transport refrigerating device (1) or the refrigerant leakage determining device (60) is turned on at the request of the user. ) Is completed, and at least one of the cases when the pre-use inspection of the transportation refrigerating device (1) is carried out, the determination result of the presence or absence of the refrigerant leakage, or the prediction of the occurrence time of the refrigerant leakage. Notify the result
The refrigerating apparatus according to claim 9. A refrigerating device (1) having a compressor (11), a condenser (12), a depressurizing device (14A, 14B), and an evaporator (13), and including a refrigerant circuit (20) configured to circulate the refrigerant. ), Which is a method for determining refrigerant leakage.
A data storage step for storing data related to the operation of the refrigerating apparatus (1), and
The first index value is calculated from the data related to the operation of the refrigerating apparatus (1) in the first period prior to the time when the index value is calculated, and the index value is longer than the length of the first period. The first calculation step of calculating the second index value from the data related to the operation of the refrigerating apparatus (1) in the second period prior to the time when the calculation of
A second calculation step for calculating the degree of deviation of the first index value from the second index value based on the first index value and the second index value calculated in the first calculation step.
A determination step of calculating the change tendency of the degree of divergence in the time series and predicting the timing of refrigerant leakage based on the change tendency of the degree of divergence in the time series.
Have,
Each of the first index value and the second index value is a discharge side refrigerant temperature ratio or a discharge side refrigerant pressure ratio.
The discharge-side refrigerant temperature ratio is a value defined by the ratio of the predicted value of the discharge-side refrigerant temperature of the compressor (11) to the measured value of the discharge-side refrigerant temperature of the compressor (11).
The discharge-side refrigerant pressure ratio is a value defined by the ratio of the predicted value of the discharge-side refrigerant pressure of the compressor (11) to the measured value of the discharge-side refrigerant pressure of the compressor (11). ,
The predicted values of the discharge side refrigerant temperature of the compressor (11) are the condensation temperature and the evaporation temperature when the amount of refrigerant charged in the refrigerant circuit (20) is within an appropriate range, and the expansion valve (14A) which is the decompression device. , 14B), the operating frequency of the compressor (11), and the rotation speed of the compressor (11) are used as variables for regression analysis to supply power to the refrigerating apparatus (1). Calculated for each power frequency and power voltage of the source power supply
The predicted values of the refrigerant pressure on the discharge side of the compressor (11) are the condensation pressure and evaporation pressure when the amount of refrigerant charged in the refrigerant circuit (20) is within an appropriate range, and the expansion valve (expansion valve) which is the decompression device. By regression analysis with at least one of the opening degree of 14A, 14B), the operating frequency of the compressor (11), and the rotation speed of the compressor (11) as variables, the power to the refrigerating apparatus (1) is supplied. Calculated for each power supply frequency and power supply voltage of the power supply source
The data relating to the operation of the refrigerating apparatus (1) in the first period is the data for the most recent day at the time point.
The data relating to the operation of the refrigerating apparatus (1) in the second period is the data for the latest 10 days or more and 30 days or less at the time point. Refrigerant leakage determination method.

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