WO2020075262A1

WO2020075262A1 - Failure sign detection device

Info

Publication number: WO2020075262A1
Application number: PCT/JP2018/037896
Authority: WO
Inventors: 貴玄中村
Original assignee: 三菱電機株式会社
Priority date: 2018-10-11
Filing date: 2018-10-11
Publication date: 2020-04-16
Also published as: JPWO2020075262A1; JP6976454B2

Abstract

This failure sign detection device detects a failure sign in equipment that is related to air-conditioning and operates with electric power supplied from a power supply via a power conversion device. The failure sign detection device is provided with: a feature amount obtainment unit which obtains a feature amount of the equipment on the basis of equipment-related information about the equipment, the equipment-related information being inputted from the equipment; a temperature increase estimation unit which estimates a temperature increase amount of the internal structure of the equipment on the basis of the obtained feature amount; a storage unit which stores a threshold value for the temperature increase amount; and a determination unit which determines the likelihood of a failure of the equipment and a degree of damage to the internal structure on the basis of a result of comparison between the estimated temperature increase amount and the threshold value.

Description

Failure sign detection device

The present invention relates to a failure precursor detection device for detecting a precursor of a failure in equipment equipment mounted on a refrigeration and air conditioning equipment.

Conventionally, various methods for detecting abnormalities in refrigeration and air conditioning equipment have been proposed. For example, Patent Document 1 discloses a method of estimating a motor temperature using a current, a voltage, and a control constant of a motor that drives a compressor, and detecting an abnormality inside the compressor based on the estimation result.

Patent Document 2 discloses a method of detecting a pulsation value with respect to an average current value of a motor that drives a compressor and a rotation speed of the motor, and detecting an abnormality inside the compressor based on the detected pulsation value and the rotation speed. It is disclosed. In this method, the internal state of the compressor is estimated by analyzing the magnitude and phase of the current of each phase of the three-phase current output to the compressor motor and estimating the torque or rotation speed of the motor. .

In Patent Document 3, a weight coefficient is arranged on a map in which the suction pressure of the refrigerant in the compressor is the horizontal axis and the discharge pressure is the vertical axis, and the weight coefficient determined by the acquired suction pressure and discharge pressure of the refrigerant is used. Based on this, a method for diagnosing an abnormality inside the compressor is disclosed. In this method, when the temperature rises inside the compressor due to an abnormality such as poor lubrication, the temperature inside the compressor is estimated by using the influence of the temperature rise on the temperature and pressure of the refrigerant circuit. It

Japanese Patent Laid-Open No. 2004-201425 International Publication No. 2017/042949 JP 2004-85088 A

By the way, the motor that drives the compressor is affected by the heat radiation from the constant contact with the refrigerant and the heat capacity of the motor material itself. Therefore, the motor temperature does not instantly rise when an abnormality occurs. That is, when the motor temperature rises due to an abnormality inside the compressor, it is considered that at least the abnormality continues for several minutes. Therefore, as described in Patent Document 1, the method of detecting an abnormality inside the compressor by using the motor temperature can detect an abnormality that continues until the motor temperature rises. Abnormalities that do not continue until the motor temperature rises may be overlooked.

Also, the motor current value varies depending on the motor specifications and load conditions. Therefore, in order to set the threshold value for detecting an abnormality based on the normal time, it is necessary to measure the normal value of the entire operating condition range for each motor model using an actual machine. Therefore, as described in Patent Document 2, the method of detecting the abnormality inside the compressor with high accuracy using the pulsation value with respect to the average current value of the motor requires a huge development load.

Furthermore, an increase in temperature inside the compressor that causes changes in the temperature and pressure of the refrigerant circuit occurs when the inside of the compressor is already in a serious failure state. Therefore, as described in Patent Document 3, the method of detecting an abnormality inside the compressor based on the suction pressure and the discharge pressure of the compressor cannot detect the abnormality before a serious abnormality occurs. .

Also, in order to place the weighting factors on the map based on the suction pressure and the discharge pressure of the refrigerant in the compressor, it is necessary to measure the entire range of the map using an actual machine. In other words, a huge development load is required for the method of detecting an abnormality inside the compressor by using the weighting coefficient arranged on the map based on the suction pressure and the discharge pressure of the refrigerant.

The present invention has been made in view of the above problems, and quickly and reliably detects a precursor of a failure in equipment such as a compressor related to air conditioning, and accurately determines the degree of damage to the internal structure of the equipment. It is an object of the present invention to provide a failure sign detection device that can be used.

The failure sign detection device of the present invention is a failure sign detection device that operates with electric power supplied from a power source via a power conversion device, and detects a sign of a failure in equipment equipment related to air conditioning, A feature amount acquisition unit that obtains a feature amount of the facility device based on the input device-related information about the facility device, and estimates a temperature rise amount of the internal structure of the facility device based on the obtained feature amount. A temperature rise estimation unit, a storage unit that stores a threshold value for the temperature rise amount, and a possibility of failure of the equipment and damage to the internal structure based on a comparison result of the estimated temperature rise amount and the threshold value. And a determination unit that determines the degree.

According to the present invention, the feature amount of the facility device is extracted based on the input device-related information, and the temperature rise amount of the internal structure of the facility device is estimated based on the extracted feature amount. Then, the estimated temperature increase amount and the threshold value are compared to determine the possibility of failure and the degree of damage to the equipment. Therefore, a sign of a failure in the equipment related to air conditioning can be detected quickly and reliably, and the degree of damage to the internal structure of the equipment can be accurately determined.

1 is a schematic diagram showing an example of a configuration of an air conditioner to which a failure sign detection device according to a first embodiment is applied. FIG. 3 is a block diagram showing an example of a configuration of a failure precursor detection device according to the first embodiment. It is a hardware block diagram which shows an example of a structure of the failure sign detection apparatus of FIG. It is a hardware block diagram which shows the other example of a structure of the failure sign detection apparatus of FIG. 5 is a flowchart showing an example of the flow of failure precursor detection processing by the failure precursor detection device according to the first embodiment.

Embodiment 1.
Hereinafter, the failure sign detection device according to the first embodiment of the present invention will be described. The failure sign detection device according to the first embodiment is applied to, for example, an air conditioner and detects a sign of a failure of equipment such as a compressor related to air conditioning.

[Configuration of Air Conditioner 100]
First, the configuration of the air conditioning apparatus 100 to which the failure sign detection device 1 according to the first embodiment is applied will be described. FIG. 1 is a schematic diagram showing an example of the configuration of an air conditioner 100 to which the failure sign detection device 1 according to the first embodiment is applied. The air conditioner 100 of FIG. 1 performs a cooling operation or a heating operation by a heat pump system.

As shown in FIG. 1, the air conditioning apparatus 100 includes a compressor 101, a condenser 102, an expansion device 103, an evaporator 104, a control device 105, and a power conversion device 110. In the air conditioner 100, the compressor 101, the condenser 102, the expansion device 103, and the evaporator 104 are sequentially connected by a refrigerant pipe, thereby forming a refrigerant circuit in which the refrigerant circulates in the refrigerant pipe.

Among these, the compressor 101 has a compression element 101a for compressing the refrigerant and a motor 101b connected to the compression element 101a and supplied with electric power by the power conversion device 110. The power conversion device 110 receives power supply from the power supply 200, supplies the converted power to the motor 101b, and drives the motor 101b to rotate. The rotation speed of the motor 101b is controlled by the control device 105.

The condenser 102 exchanges heat between the refrigerant and air to condense the refrigerant. The expansion device 103 expands the refrigerant. The opening degree of the expansion device 103 is controlled by the control device 105. The evaporator 104 exchanges heat between the refrigerant and air to evaporate the refrigerant.

The control device 105 controls the overall operation of the air conditioning device 100 based on information received from various sensors (not shown) provided in each part of the air conditioning device 100. In the first embodiment, the control device 105 controls the motor 101b of the compressor 101 based on the information received from the failure sign detection device 1 described later. The control device 105 realizes various functions by executing software on an arithmetic device such as a microcomputer, or is configured by hardware such as a circuit device that realizes various functions.

(Fault sign detection device 1)
In addition, in the first embodiment, the air-conditioning apparatus 100 includes the failure sign detection device 1. FIG. 2 is a block diagram showing an example of the configuration of the failure sign detection device 1 according to the first embodiment. As illustrated in FIG. 2, the failure sign detection device 1 includes a feature amount acquisition unit 11, a temperature rise estimation unit 12, a determination unit 13, a storage unit 14, and a notification unit 15. The failure sign detection device 1 realizes various functions by executing software on a computing device such as a microcomputer, or is configured by hardware such as a circuit device that realizes various functions.

The feature amount acquisition unit 11 receives device-related information from the outside, and acquires the feature amount based on this device-related information. The feature amount is a physical amount having a feature related to a precursor of a failure of the compressor 101, and is, for example, power consumption of the motor 101b that drives the compressor 101. The feature amount is acquired, for example, using an arithmetic expression or the like according to the input device-related information. The device-related information is a physical amount related to the operation of equipment such as the compressor 101, which is necessary for acquiring the feature amount, and is, for example, information obtained when the compressor 101 operates. The device-related information is, for example, a primary input from the power supply 200 that is input to the power conversion device 110, a secondary input that is output from the power conversion device 110, and is input to the motor 101b that drives the compressor 101. is there.

The temperature rise estimation unit 12 estimates the temperature rise amount of the internal structure of the compressor 101 based on the characteristic amount acquired by the characteristic amount acquisition unit 11. The temperature rise amount is estimated using, for example, an arithmetic expression according to the acquired feature amount.

The determination unit 13 compares the amount of temperature increase estimated by the temperature increase estimation unit 12 with the lower limit threshold value stored in the storage unit 14, and determines the possibility of failure of the compressor 101 based on the comparison result. In addition, when the determination unit 13 determines that the compressor 101 may fail, the determination unit 13 compares the temperature increase amount with the determination threshold value stored in the storage unit 14 to determine the degree of damage inside the compressor 101. judge. The determination unit 13 outputs information indicating the determination result to the notification unit 15 and the control device 105.

The lower limit threshold is a threshold indicating the boundary of whether or not the compressor 101 may fail. The determination threshold value is used to determine the degree of damage inside the compressor 101 when it is determined that the compressor 101 may “fail”. The determination threshold value is larger than the lower limit threshold value and is set stepwise.

The storage unit 14 stores in advance various information used when processing is performed by each unit of the failure sign detection device 1. In the first embodiment, the storage unit 14 stores in advance a lower limit threshold value and one or a plurality of determination threshold values set for the temperature increase amount used in the determination unit 13.

The notification unit 15 notifies the possibility of failure and the degree of damage to the compressor 101 according to the determination result of the determination unit 13. As the notification unit 15, for example, a display and a display unit such as an LED (Light Emitting Diode) or a voice output unit such as a speaker is used. When the notification unit 15 is a display, information according to the determination result is displayed in characters or figures. When the notification unit 15 is an LED, information corresponding to the determination result is displayed by lighting, blinking, or extinguishing. When the notification unit 15 is a speaker, information according to the determination result is notified by voice.

3 is a hardware configuration diagram showing an example of the configuration of the failure precursor detection device 1 of FIG. When various functions of the failure sign detection device 1 are executed by hardware, the failure sign detection device 1 of FIG. 2 includes a processing circuit 21 and an output device 22 as shown in FIG. Each function of the feature amount acquisition unit 11, the temperature rise estimation unit 12, the determination unit 13, and the storage unit 14 of FIG. 2 is realized by the processing circuit 21. Further, the notification unit 15 is the output device 22 of FIG.

When each function is executed by hardware, the processing circuit 21 includes, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), and an FPGA (Field-Programmable Gate). Array) or a combination thereof. The function of each of the feature amount acquisition unit 11, the temperature rise estimation unit 12, the determination unit 13, and the storage unit 14 may be realized by the processing circuit 21, or the function of each unit may be realized by one processing circuit 21. Good.

FIG. 4 is a hardware configuration diagram showing another example of the configuration of the failure precursor detection device 1 of FIG. When various functions of the failure sign detection device 1 are executed by software, the failure sign detection device 1 of FIG. 2 includes a processor 31, a memory 32, and an output device 33, as shown in FIG. The functions of the characteristic amount acquisition unit 11, the temperature rise estimation unit 12, the determination unit 13, and the storage unit 14 are realized by the processor 31 and the memory 32. The notification unit 15 in FIG. 2 is the output device 33 in FIG.

When each function is executed by software, the functions of the feature amount acquisition unit 11, the temperature rise estimation unit 12, and the determination unit 13 are realized by software, firmware, or a combination of software and firmware. The software and firmware are described as programs and stored in the memory 32. The processor 31 realizes the function of each unit by reading and executing the program stored in the memory 32.

As the memory 32, for example, a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an EPROM (Erasable and Programmable ROM), and an EEPROM (Electrically erasable and nonvolatile ROM) such as an EEPROM (Electrically erasable and nonvolatile). Is used. As the memory 32, for example, a removable recording medium such as a magnetic disk, a flexible disk, an optical disk, a CD (Compact Disc), an MD (Mini Disc), and a DVD (Digital Versatile Disc) may be used.

[Operation of Air Conditioner 100]
The operation of the air conditioner 100 will be described with reference to FIG. When the motor 101b of the compressor 101 is rotationally driven by the power converter 110, the compression element 101a of the compressor 101 connected to the motor 101b compresses the low-temperature low-pressure refrigerant, and the compressor 101 discharges the high-temperature high-pressure gas refrigerant. To do. The high-temperature and high-pressure gas refrigerant discharged from the compressor 101 flows into the condenser 102.

The high-temperature and high-pressure gas refrigerant flowing into the condenser 102 exchanges heat with the air and radiates heat to condense to become a high-pressure liquid refrigerant, which then flows out of the condenser 102. The high-pressure liquid refrigerant that has flowed out of the condenser 102 is expanded and decompressed by the expansion device 103, becomes a low-temperature low-pressure gas-liquid two-phase refrigerant, and flows into the evaporator 104.

The low-temperature low-pressure gas-liquid two-phase refrigerant that has flowed into the evaporator 104 cools the air by exchanging heat with the air to absorb heat and evaporate, and flows out of the evaporator 104 as a low-temperature low-pressure gas refrigerant. The low-temperature low-pressure gas refrigerant flowing out from the evaporator 104 is sucked into the compressor 101 and compressed again. Hereinafter, the above operation is repeated.

In FIG. 1, the air conditioner 100 is described as an example, but the present invention is not limited to this, and may be applied to, for example, a heat pump device, a refrigeration device, and other refrigeration cycle devices in general.

[Pre-failure detection processing]
Next, a failure precursor detection process by the failure precursor detection device 1 according to the first embodiment will be described. In the compressor 101 as a facility device related to air conditioning, it is generally known that the temperature of the internal structure rises when a failure occurs due to a shortage or depletion of oil for sliding parts such as bearings. . This is because the oil is insufficient and the frictional resistance of the sliding portion increases, so that heat due to friction is generated.

On the other hand, the temperature rise of the internal structure affects the device-related information, which is a physical quantity having characteristics related to the precursor of the compressor 101 failure. For example, an increase in the frictional resistance between the shaft and the bearing of the compressor 101 as the temperature of the internal structure increases causes a change in the input to the compressor 101 and the torque of the motor 101b that drives the compressor 101, which is different from the normal state. Occurs.

In this way, there is a correlation between the temperature rise amount of the internal structure of the compressor 101 and the feature amount. Then, the characteristic amount can be acquired from the device-related information, which is a physical amount related to the operation of the compressor 101. Therefore, if the temperature rise amount can be estimated based on the device-related information affected by the temperature rise, the failure in the compressor 101 can be detected.

Further, the temperature rise of the internal structure of the compressor 101 occurs not at the time of the complete failure of the compressor 101 but at the precursory stage of the failure, and the degree of damage inside the compressor 101 increases as the amount of temperature increase increases. Becomes higher. That is, the degree of damage inside the compressor 101 can be determined based on the amount of temperature increase.

Therefore, in the first embodiment, the characteristic amount regarding the failure in the equipment such as the compressor 101 is acquired, and the temperature rise amount of the internal structure of the equipment is estimated from the acquired characteristic amount. Then, based on the estimated amount of temperature rise, the sign of failure of the equipment and the degree of damage are detected.

FIG. 5 is a flowchart showing an example of the flow of failure precursor detection processing by the failure precursor detection device 1 according to the first embodiment. First, when device-related information is input to the feature amount acquisition unit 11 from the outside, the feature amount acquisition unit 11 acquires the feature amount based on the input device-related information in step S1. In step S2, the temperature rise estimation unit 12 estimates the temperature rise amount of the internal structure of the compressor 101 based on the characteristic amount acquired by the characteristic amount acquisition unit 11.

In step S3, the determination unit 13 compares the temperature increase amount estimated in step S2 with the lower limit threshold value stored in the storage unit 14, and determines whether the compressor 101 may fail. . As a result of the comparison, when the amount of temperature increase exceeds the lower limit threshold value (step S3; Yes), the determination unit 13 determines in step S4 that the compressor 101 may “failure”.

Next, the determination unit 13 determines the degree of damage inside the compressor 101 in step S5. One or more determination threshold values stored in the storage unit 14 are used to determine the degree of damage to the compressor 101, and the degree of damage to the compressor 101 is determined based on the relationship between the temperature increase amount and one or more determination threshold values. Is determined.

The determination unit 13 outputs information indicating the possibility of failure of the compressor 101 and the degree of damage to the notification unit 15 and the control device 105 of the air conditioning apparatus 100. As a result, the notification unit 15 notifies the possibility of failure of the compressor 101 and the degree of damage in step S6. At this time, the notification unit 15 may give different notifications according to the determined damage degree so that the damage degree determined in step S5 can be identified. Specifically, when the notification unit 15 is a display, the notification unit 15 displays information indicating the possibility of failure of the compressor 101 such as “the compressor 101 may fail” and the degree of damage in that case. And information to display.

On the other hand, in step S3, when the amount of temperature increase is less than or equal to the lower limit threshold value (step S3; No), the determination unit 13 determines in step S7 that the compressor 101 is “normal”.

As described above, in the failure sign detection device 1 according to the first embodiment, the temperature rise amount of the internal structure of the compressor 101 is estimated based on the feature amount acquired from the device-related information. Then, based on the estimated temperature increase amount, the possibility of failure of the compressor 101 and the degree of damage to the internal structure of the compressor 101 are determined. Accordingly, the possibility of failure and the degree of damage of the compressor 101 can be determined without actually measuring the temperature of the internal structure of the compressor 101. Therefore, it is possible to reliably detect the failure of the compressor 101 before the compressor 101 cannot actually operate due to damage. Further, the failure of the compressor 101 can be quickly detected before the compressor 101 completely fails.

In the first embodiment, the estimated temperature increase amount is compared with a preset lower limit threshold value, and when the temperature increase amount exceeds the lower limit threshold value, it is determined that the compressor 101 may fail. It Thereby, the possibility of failure of the compressor 101 can be easily determined.

In the first embodiment, when it is determined that the compressor 101 may fail, the temperature increase amount is compared with one or more determination threshold values, and based on the relationship between the temperature increase amount and the determination threshold value. The degree of damage to the internal structure of the compressor 101 is determined. Thereby, the degree of damage to the compressor 101 can be easily determined.

Embodiment 2.
Next, a second embodiment of the present invention will be described. In the second embodiment, a case where the power consumption of the motor 101b of the compressor 101 is applied as a characteristic amount will be described. In the following description, the same parts as those in the first embodiment will be designated by the same reference numerals, and detailed description thereof will be omitted.

[Configuration of Air Conditioner 100]
The configuration of the air conditioning apparatus 100 according to the second embodiment is similar to that of the air conditioning apparatus 100 according to the first embodiment shown in FIG. The configuration of the failure sign detection device 1 is also the same as that of the failure sign detection device 1 according to the first embodiment shown in FIG.

In the second embodiment, the feature quantity acquisition unit 11 of the failure sign detection device 1 of FIG. 2 has a primary input (primary current, primary current) input from the power supply 200 to the power conversion device 110 as device-related information. Voltage), the rotation speed of the compressor 101, the discharge pressure, and the suction pressure are input. The device-related information is measured using an external measuring device or the like, and the measurement result is input to the feature amount acquisition unit 11.

The characteristic amount acquisition unit 11 acquires the power consumption of the motor 101b as a characteristic amount based on the input primary input, the rotation speed of the compressor 101, the discharge pressure, and the suction pressure.

The temperature rise estimation unit 12 estimates the temperature rise amount of the internal structure of the compressor 101 based on the power consumption acquired by the feature amount acquisition unit 11 and the specification information stored in the storage unit 14. The estimation of the temperature rise amount will be described later. The specification information is various parameters determined by the specifications of the internal structure of the compressor 101. For example, the specification information is the volume of the bearing, which is the sliding portion in the compressor 101, and the specific heat and density of the material used for the bearing.

Like the first embodiment, the storage unit 14 stores in advance a lower limit threshold and one or more determination thresholds. Further, in the second embodiment, the storage unit 14 stores in advance the specification information used when the temperature rise estimating unit 12 estimates the temperature rise amount.

[Estimation of temperature rise]
As described in the first embodiment, the temperature rise of the internal structure of the compressor 101 occurs due to the increase of the frictional resistance of the sliding portion. As a result, the torque of the motor 101b of the compressor 101 changes differently from the normal time.

The torque of the motor 101b is proportional to the input power. Specifically, when the torque of the motor 101b changes, the primary input input from the power supply 200 to the power converter 110 also changes accordingly. When the primary input from the power supply 200 changes, the power consumption of the motor 101b obtained from the primary current and the primary voltage, which are the primary inputs, also changes.

Therefore, in the second embodiment, the power consumption of the motor 101b that drives the compressor 101 is applied as a characteristic amount, and the amount of temperature increase that occurs according to the change in the power consumption is estimated. Then, the possibility of failure and the degree of damage of the compressor 101 are determined based on the estimated temperature rise amount.

(Acquisition of feature quantity)
First, the power consumption of the motor 101b as the characteristic amount in the second embodiment is calculated based on the equation (1). In Expression (1), “output” is output power from the power supply 200. “Efficiency” is the compressor efficiency of the compressor 101.

The output power from the power supply 200 can be obtained by multiplying the primary current input from the power supply 200 to the power converter 110 and the primary voltage. Further, the efficiency of the compressor 101 can be obtained by obtaining a function determined by the rotation speed of the compressor 101 and the pressure difference between the discharge pressure and the suction pressure of the refrigerant.

(Estimation of temperature rise)
Next, the temperature increase amount ΔT [° C.] is calculated using the equation (2) based on the power consumption and the specification information. In Expression (2), the power difference ΔP [W] indicates the difference in power consumption at two measurement time points. The duration t [sec] indicates a time difference between two measurement points when calculating the power difference ΔP. The specific heat c [kJ / kg · ° C.] indicates the specific heat of the material used for the sliding portion such as the bearing in the compressor 101. The density ρ [kg / m ³ ] indicates the density of the material used for the sliding portion of the compressor 101. The volume V [m ³ ] indicates the volume of the sliding portion in the compressor 101. The specific heat c, the density ρ, and the volume V are information included in the specification information stored in the storage unit 14.

Here, the power difference ΔP is obtained by taking the difference in power at adjacent points sampled at the set interval. Specifically, the power difference ΔP is the difference in power between the time point n and the time point n−1. Further, the duration t is the length of the adjacent sampling time, specifically, the time difference between the time point n and the time point n-1.

[Pre-failure detection processing]
As shown in the flowchart of FIG. 5, in step S1, the primary current and the primary voltage as the device-related information, the rotation speed of the compressor 101, the discharge pressure, and the suction pressure are input to the feature amount acquisition unit 11. To be done. The characteristic amount acquisition unit 11 acquires the power consumption of the motor 101b as a characteristic amount using Expression (1) based on these device-related information.

In step S2, the temperature rise estimation unit 12 uses the formula (2) to calculate the temperature rise amount of the internal structure of the compressor 101 based on the power consumption as the feature amount acquired by the feature amount acquisition unit 11 and the specification information. Calculate ΔT. The processes of steps S3 to S7 are the same as those in the first embodiment.

(First modification)
A first modification of the second embodiment will be described. In the first modification, as device-related information, the secondary input (secondary power) input from the power converter 110 to the motor 101b of the compressor 101, and the rotation speed, discharge pressure, and suction pressure of the compressor 101. Is input to the failure sign detection device 1. The secondary input (secondary power) as the device-related information is acquired using a three-phase power meter or a two-power meter method. The characteristic amount acquisition unit 11 acquires the power consumption of the motor 101b as a characteristic amount using Expression (1) based on these device-related information.

(Fault sign detection process)
As shown in the flowchart of FIG. 5, in step S1, the secondary power as the device-related information, the rotation speed of the compressor 101, the discharge pressure, and the suction pressure are input to the feature amount acquisition unit 11. The characteristic amount acquisition unit 11 acquires the power consumption of the motor 101b as a characteristic amount using Expression (1) based on these device-related information. The processes in steps S2 to S7 are the same as those in the second embodiment.

(Second modified example)
A second modification of the second embodiment will be described. In the second modified example, as the device-related information, the q-axis current Iq and the q-axis voltage Vq in the power converter 110, the rotation speed of the compressor 101, the discharge pressure, and the suction pressure are input to the failure precursor detection device 1. It The q-axis current Iq and the q-axis voltage Vq as the device-related information can be acquired from the power converter 110. The characteristic amount acquisition unit 11 acquires the power consumption of the motor 101b as a characteristic amount using Expression (1) based on these device-related information.

(Fault sign detection process)
As shown in the flowchart of FIG. 5, in step S1, the feature amount acquisition unit 11 causes the q-axis current Iq and the q-axis voltage Vq as device-related information, and the rotation speed, discharge pressure, and suction pressure of the compressor 101. Is entered. The characteristic amount acquisition unit 11 acquires the power consumption of the motor 101b as a characteristic amount using Expression (1) based on these device-related information. The processes in steps S2 to S7 are the same as those in the second embodiment.

As described above, in the failure sign detection device 1 according to the second embodiment, the specification information indicating the specifications of the internal structure of the compressor 101 is stored in advance, and the power consumption of the compressor 101 is acquired as the feature amount. To be done. Then, the temperature rise amount of the internal structure of the compressor 101 is estimated based on the power consumption and the specification information. As a result, it is possible to estimate the temperature rise amount according to the material amount of the compressor 101 and the like, and it is possible to accurately estimate the possibility of failure and the degree of damage of the compressor 101.

At this time, the power consumption as the characteristic amount may be acquired based on the primary power supplied from the power supply 200 to the power converter 110, or may be supplied from the power converter 110 to the motor 101b of the compressor 101. It may be acquired based on the next power. The power consumption may be acquired based on the q-axis current and the q-axis voltage in the power converter 110.

Embodiment 3.
Next, a third embodiment of the present invention will be described. In the third embodiment, a case will be described in which, of the three-phase power supplied to the motor 101b of the compressor 101, for example, a power ratio between frames based on a U-phase current is applied as a feature amount. In the following description, the same parts as those in the first and second embodiments are designated by the same reference numerals, and detailed description thereof will be omitted.

[Configuration of Air Conditioner 100]
The configuration of the air conditioning apparatus 100 according to the third embodiment is similar to that of the air conditioning apparatus 100 according to the first and second embodiments shown in FIG. The configuration of the failure sign detection device 1 is also the same as that of the failure sign detection device 1 according to the first and second embodiments shown in FIG.

In the third embodiment, the U-phase current of the three-phase power supplied from the power converter 110 is input to the characteristic amount acquisition unit 11 of the failure sign detection device 1 of FIG. 2 as the device-related information. . The U-phase current as the device-related information is measured using an external measuring device or the like, and the measurement result is input to the feature amount acquisition unit 11.

The characteristic amount acquisition unit 11 acquires the power ratio Energy_d as a characteristic amount based on the input U-phase current. The power ratio Energy_d indicates the ratio of the power value Energy (τ) and the power value Energy (τ-1) in each of the frame τ, which is a set of preset number of samples, and the immediately preceding frame τ-1. .

The temperature rise estimation unit 12 estimates the temperature rise amount of the internal structure of the compressor 101 based on the power ratio Energy_d acquired by the feature amount acquisition unit 11 and the specification information stored in the storage unit 14. The estimation of the temperature rise amount will be described later.

Like the first embodiment, the storage unit 14 stores in advance a lower limit threshold and one or more determination thresholds. Further, in the third embodiment, as in the second embodiment, the storage unit 14 stores in advance the specification information used when the temperature increase estimation unit 12 estimates the temperature increase amount.

[Estimation of temperature rise]
The torque of the motor 101b in the compressor 101 is proportional to the current of one phase of the three-phase current in the stepless state, for example, the U-phase current. Specifically, when the torque of the motor 101b changes, the U-phase current supplied to the motor 101b also changes accordingly. Further, when the U-phase current changes, the power ratio Energy_d of the motor 101b obtained from the U-phase current also changes. Note that "step out" means that the instruction frequency for the motor 101b deviates from the actual frequency.

Therefore, in the third embodiment, the power ratio Energy_d of the motor 101b that drives the compressor 101 is applied as a feature amount, and the temperature rise amount that occurs according to the power ratio Energy_d is estimated. Then, the possibility of failure and the degree of damage of the compressor 101 are determined based on the estimated temperature rise amount.

(Acquisition of feature quantity)
First, in order to calculate the power ratio Energy_d of the motor 101b as the feature amount in the third embodiment, the power value Power (τ) in the frame τ is calculated. The power value Power (τ) is calculated based on the equation (3). Here, the frame τ is a set of a preset number of samples, and x _τ (n) in the equation (3) represents the U-phase current at the sampling time n in the frame τ.

Next, the power value Energy (τ) obtained by logarithmically converting the power value Power (τ) is calculated. The power value Energy (τ) is calculated based on the equation (4).

Then, based on the power value Energy (τ) in the frame τ and the power value Energy (τ-1) in the immediately preceding frame τ-1, the power ratio Energy_τ of the power value Energy (τ) with respect to the power value Energy (τ-1). Is calculated based on the equation (5).

(Estimation of temperature rise)
Next, the temperature increase amount ΔT is estimated based on the power ratio Energy_d and the specification information. In the third embodiment, a map in which the horizontal axis represents the rotation speed of the compressor 101 and the vertical axis represents the differential pressure of the refrigerant in the compressor 101 is created for each preset power ratio. The map shows the heat generation amount due to the torque fluctuation of the motor 101b estimated from the fluctuation width of the power ratio Energy_d. Therefore, the temperature increase amount ΔT corresponding to the heat generation amount can be estimated by referring to the material properties of the sliding portion such as the bearing of the compressor 101 based on the specification information.

[Pre-failure detection processing]
As shown in the flowchart of FIG. 5, the U-phase current as the device-related information is input to the feature amount acquisition unit 11 in step S1. The characteristic amount acquisition unit 11 acquires the power ratio Energy_d as a characteristic amount using Expressions (3) to (5) based on the U-phase current.

In step S2, the temperature rise estimating unit 12 creates a map based on the power ratio Energy_d as the feature amount acquired by the feature amount acquiring unit 11, and based on the heat generation amount and the specification information described in the created map. Estimate the temperature rise amount ΔT of the internal structure of the compressor 101. The processes of steps S3 to S7 are the same as those in the first embodiment.

(Third Modification)
A third modification of the third embodiment will be described. In the third modification, as in the third embodiment, the U-phase current supplied from the power converter 110 to the motor 101b of the compressor 101 is input to the failure sign detection device 1 as the device-related information. Then, the power ratio Power_d between frames is acquired as a feature amount based on the input U-phase current.

(Fault sign detection process)
As shown in the flowchart of FIG. 5, the U-phase current as the device-related information is input to the feature amount acquisition unit 11 in step S1. The feature amount acquisition unit 11 calculates the power value Power (τ) in the frame τ based on the U-phase current using the equation (3). Then, the feature amount acquisition unit 11 acquires the power ratio Power_d as the feature amount based on the calculated power value Power (τ) in the frame τ and the power value Power (τ-1) in the immediately preceding frame τ-1. .

In step S2, the temperature increase estimation unit 12 creates a map based on the power ratio Power_d as the feature amount, as in the third embodiment, and based on the heat generation amount and the specification information described in the created map, The temperature rise amount ΔT of the internal structure of the compressor 101 is calculated. The processes in steps S3 to S7 are the same as those in the third embodiment.

(Fourth Modification)
A fourth modified example of the third embodiment will be described. In the fourth modification, similar to the third and third modifications, the U-phase current supplied from the power converter 110 to the motor 101b of the compressor 101 as the device-related information is the failure sign detector 1. Entered in. Then, based on the input U-phase current, the difference effective value RMS_d, which is the difference value of the effective value (RMS) of the U-phase current between frames, is acquired as the feature amount.

(Fault sign detection process)
As shown in the flowchart of FIG. 5, the U-phase current as the device-related information is input to the feature amount acquisition unit 11 in step S1. The feature amount acquisition unit 11 calculates the effective value RMS (τ) of the U-phase power in the frame τ based on the U-phase current. Then, the characteristic amount acquisition unit 11 acquires the difference effective value RMS_d as the characteristic amount based on the calculated effective value RMS (τ) in the frame τ and the effective value RMS (τ-1) in the immediately preceding frame τ-1. To do.

In step S2, the temperature rise estimating unit 12 creates a map based on the difference effective value RMS_d as the feature amount, as in the third embodiment, and based on the heat generation amount and the specification information described in the created map. A temperature increase amount ΔT of the internal structure of the compressor 101 is calculated. The processes in steps S3 to S7 are the same as those in the third embodiment.

(Fifth Modification)
A fifth modification of the third embodiment will be described. In the fifth modified example, similar to the third, third, and fourth modified examples, the U-phase current supplied from the power converter 110 to the motor 101b of the compressor 101 as the device-related information. Is input to the failure sign detection device 1. Then, based on the input U-phase current, a difference amplitude value A_d, which is a difference value of the amplitude of the U-phase current between frames, is acquired as a feature amount. The amplitude value is the maximum amplitude value obtained from the maximum value in the positive direction and the maximum value in the negative direction of one wavelength.

(Fault sign detection process)
As shown in the flowchart of FIG. 5, the U-phase current as the device-related information is input to the feature amount acquisition unit 11 in step S1. The feature amount acquisition unit 11 calculates the amplitude A (τ) of the U-phase power in the frame τ based on the U-phase current. Then, the characteristic amount acquisition unit 11 acquires the difference amplitude value A_d as the characteristic amount based on the calculated amplitude A (τ) in the frame τ and the calculated amplitude A (τ-1) in the immediately preceding frame τ-1.

In step S2, the temperature rise estimation unit 12 creates a map based on the difference amplitude value A_d as the feature amount, and based on the heat generation amount and the specification information described in the created map, the internal structure of the compressor 101 is determined. The temperature increase amount ΔT is calculated. The processes in steps S3 to S7 are the same as those in the third embodiment.

As described above, in the failure sign detection device 1 according to the third embodiment, the characteristic amount is acquired based on the U-phase current supplied to the compressor 101. In this case, the feature amount is a power ratio that is a ratio between the power value in the set frame and the power value in the immediately preceding frame.

Also, as the feature amount, a difference effective value that is a difference between the effective value of the U-phase current in the setting frame and the effective value of the U-phase current in the immediately preceding frame may be used. Further, as the feature amount, a difference amplitude value A_d that is a difference between the amplitude of the U-phase current in the set frame and the amplitude of the U-phase current in the immediately preceding frame may be used.

Fourth Embodiment
Next, a fourth embodiment of the invention will be described. In the fourth embodiment, a case will be described in which the difference value of the q-axis current in the power converter 110 is applied as the feature amount. In the following description, the same parts as those in the first to third embodiments are designated by the same reference numerals, and detailed description thereof will be omitted.

[Configuration of Air Conditioner 100]
The configuration of the air conditioning apparatus 100 according to the fourth embodiment is similar to that of the air conditioning apparatus 100 according to the first to third embodiments shown in FIG. The configuration of the failure sign detection device 1 is also the same as that of the failure sign detection device 1 according to the first to third embodiments shown in FIG.

In the fourth embodiment, the q-axis current Iq in the power conversion device 110 is input to the feature amount acquisition unit 11 of the failure sign detection device 1 of FIG. 2 as device-related information. The feature amount acquisition unit 11 acquires the difference value ΔIq of the q-axis current at the sampling interval as the feature amount based on the input q-axis current Iq. The temperature rise estimation unit 12 estimates the temperature rise amount ΔT of the internal structure of the compressor 101 based on the difference value ΔIq of the q-axis current acquired by the feature amount acquisition unit 11. The estimation of the temperature increase amount ΔT will be described later.

[Estimation of temperature rise]
It is known that the torque of the motor 101b is equal to the q-axis current Iq in the power converter 110. Therefore, since the difference value ΔIq of the q-axis current Iq at the sampling interval serves as it is, the temperature increase amount ΔT at the sampling interval can be estimated by using this difference value ΔIq and the equation (2). it can. In this case, the difference value ΔIq is used instead of the power difference ΔP in the equation (2).

[Pre-failure detection processing]
As shown in the flowchart of FIG. 5, the q-axis current Iq as the device-related information is input to the feature amount acquisition unit 11 in step S1. The feature amount acquisition unit 11 calculates the difference value ΔIq at the sampling interval as the feature amount based on the q-axis current Iq.

In step S2, the temperature rise estimation unit 12 calculates the temperature rise amount ΔT of the internal structure of the compressor 101 using the equation (2) based on the difference value ΔIq as the feature amount acquired by the feature amount acquisition unit 11. To do. The processes of steps S3 to S7 are the same as those in the first embodiment.

As described above, in the failure precursor detection device 1 according to the fourth embodiment, based on the difference value between the q-axis current of the power conversion device 110 in the setting frame and the q-axis current in the immediately preceding frame, and the specification information. The temperature rise amount of the internal structure of the compressor 101 can be calculated.

1 failure sign detection device, 11 feature amount acquisition unit, 12 temperature rise estimation unit, 13 determination unit, 14 storage unit, 15 notification unit, 21 processing circuit, 22 output device, 31 processor, 32 memory, 33 output device, 100 air Harmonization device, 101 compressor, 101a compression element, 101b motor, 102 condenser, 103 expansion device, 104 evaporator, 105 control device, 110 power conversion device, 200 power supply.

Claims

A failure precursor detection device that operates with electric power supplied from a power supply via a power conversion device and detects a precursor of a failure in equipment related to air conditioning,
A feature amount acquisition unit that obtains a feature amount of the facility device, based on device-related information about the facility device input from the facility device,
Based on the acquired feature amount, a temperature rise estimation unit that estimates the temperature rise amount of the internal structure of the equipment,
A storage unit that stores a threshold value for the temperature increase amount,
A failure precursor detection device comprising: a determination unit that determines a possibility of a failure of the equipment and a degree of damage to the internal structure based on a result of comparison between the estimated temperature increase amount and the threshold value.
The threshold is
Including a lower threshold that indicates the boundary of the presence or absence of failure,
The determination unit includes:
The failure sign detection device according to claim 1, wherein the temperature increase amount is compared with the lower limit threshold value, and when the temperature increase amount exceeds the lower limit threshold value, it is determined that the facility device may fail. .
The threshold is
A value greater than the lower threshold, further including one or more determination thresholds set in stages,
The determination unit includes:
When it is determined that the equipment may be damaged,
The failure sign detection device according to claim 2, wherein the degree of damage to the internal structure of the equipment is determined based on the relationship between the temperature increase amount and the one or more determination thresholds.
The feature amount acquisition unit,
Acquiring the power consumption of the equipment as the characteristic amount,
The storage unit,
Pre-store specification information indicating the specifications of the internal structure of the equipment,
The temperature rise estimation unit,
The failure sign detection device according to any one of claims 1 to 3, wherein the temperature rise amount of the internal structure of the equipment is estimated based on the power consumption of the equipment and the specification information.
The feature amount acquisition unit,
The failure sign detection device according to claim 4, wherein the power consumption is acquired based on a primary power output from the power supply to the power conversion device.
The feature amount acquisition unit,
The failure sign detection device according to claim 4, wherein the power consumption is acquired based on secondary power supplied from the power conversion device to the equipment.
The feature amount acquisition unit,
The failure sign detection device according to claim 4, wherein the power consumption is acquired based on a q-axis current and a q-axis voltage of the power conversion device.
The feature amount acquisition unit,
The failure sign detection device according to any one of claims 1 to 3, wherein the characteristic amount is acquired based on a current of any one phase of three-phase power supplied from the power conversion device to the equipment.
The feature amount acquisition unit,
Based on the one-phase current, a power value in a setting frame and a power ratio indicating a ratio of the power value in a frame immediately before the setting frame are acquired as a characteristic amount,
The storage unit,
Pre-store specification information indicating the specifications of the internal structure of the equipment,
The temperature rise estimation unit,
The failure sign detection device according to claim 8, wherein the temperature rise amount of the internal structure of the equipment is estimated based on the power ratio and the specification information.
The feature amount acquisition unit,
Based on the one-phase current, the effective value of the current in the setting frame, and obtain a difference effective value indicating the difference between the effective value of the current in the frame immediately before the setting frame as a feature amount,
The storage unit,
Pre-store specification information indicating the specifications of the internal structure of the equipment,
The temperature rise estimation unit,
The failure sign detection device according to claim 8, wherein the temperature rise amount of the internal structure of the equipment is estimated based on the difference effective value and the specification information.
The feature amount acquisition unit,
Based on the one-phase current, the amplitude of the current in the setting frame, and obtain a difference amplitude value indicating the difference between the amplitude of the current in the frame immediately before the setting frame as a feature amount,
The storage unit,
Pre-store specification information indicating the specifications of the internal structure of the equipment,
The temperature rise estimation unit,
The failure sign detection device according to claim 8, wherein the temperature rise amount of the internal structure of the equipment is estimated based on the difference amplitude value and the specification information.
The feature amount acquisition unit,
The difference between the q-axis current in the setting frame of the power converter and the q-axis current in the frame immediately before the setting frame is acquired as a feature amount,
The storage unit,
Pre-store specification information indicating the specifications of the internal structure of the equipment,
The temperature rise estimation unit,
The failure sign detection device according to claim 8, wherein the temperature rise amount of the internal structure of the equipment is estimated based on the difference between the q-axis currents and the specification information.
The failure sign detection device according to any one of claims 1 to 12, further comprising a notification unit that notifies a possibility of a failure and a degree of damage to the equipment according to a determination result of the determination unit.