Compressor and diagnostic method, device, readable storage medium and vehicle thereof

Abstract

The application provides a compressor and a diagnosis method, device, readable storage medium and vehicle thereof. The diagnosis method comprises: acquiring an input variable of a compressor controller; processing the input variable to obtain a target parameter value, the target parameter value comprising at least one of: a first target parameter value obtained by processing the input variable in a steady state time domain, a second target parameter value obtained by processing the input variable in a transient state time domain, and a third target parameter value obtained by processing the input variable in a steady state frequency domain; and determining a diagnosis result of the compressor according to a comparison result of the target parameter value and a corresponding parameter threshold value.

Description

Technical Field

[0001] This invention relates to the field of control technology, and more specifically, to a compressor, a diagnostic method and apparatus thereof, a readable storage medium, and a vehicle. Background Technology

[0002] A compressor is a product that combines mechanical components, a motor, and an electronic control system. During operation, it may experience malfunctions such as compressor pump body wear, broken teeth, insufficient oil, bearing wear, motor insulation failure, damage to electronic control components, and deterioration of thermal conductivity.

[0003] In the relevant technical solutions, compressor diagnosis is divided into two main categories. One category involves installing vibration, acceleration, and noise sensors, performing spectrum analysis on the signals from these sensors, and comparing them with standard spectra. The other category involves performing spectrum analysis on the collected current signals.

[0004] All of the above technical solutions require spectral analysis of the collected data, which requires a large amount of computation and places high demands on the hardware. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0006] Therefore, a first aspect of the present invention is to provide a method for diagnosing a compressor.

[0007] A second aspect of the present invention is that a diagnostic device for a compressor is provided.

[0008] A third aspect of the invention is that it provides another diagnostic device for compressors.

[0009] A fourth aspect of the present invention is that a readable storage medium is provided.

[0010] A fifth aspect of the present invention is that a compressor is provided.

[0011] A sixth aspect of the invention is that a vehicle is provided.

[0012] In view of this, according to a first aspect of the present invention, the present invention provides a method for diagnosing a compressor, the compressor being associated with a compressor controller, the method comprising: acquiring input variables of the compressor controller; processing the input variables to obtain target parameter values, the target parameter values ​​comprising at least one of the following: a first target parameter value obtained by processing the input variables in the steady-state time domain, a second target parameter value obtained by processing the input variables in the transient time domain, and a third target parameter value obtained by processing the input variables in the steady-state frequency domain; and determining a diagnostic result of the compressor based on a comparison result between the target parameter values ​​and corresponding parameter thresholds.

[0013] The technical solution of this application proposes a compressor diagnostic method. By running this diagnostic method, compressor fault detection can be achieved. In the above diagnostic method, the input variables input to the compressor controller are analyzed, processed and judged to achieve compressor fault diagnosis. In this process, there is no need to perform spectrum analysis. Therefore, the amount of computation required for diagnosis is relatively small, thereby reducing the hardware requirements for compressor fault diagnosis.

[0014] In addition, the compressor diagnostic method proposed in this application has the following additional technical features.

[0015] In the above technical solution, when the target parameter value includes a first target parameter value, the diagnostic result of the compressor is determined based on the comparison result between the target parameter value and the corresponding parameter threshold. Specifically, the compressor is abnormal when the first target parameter value is greater than the first parameter threshold or when the first target parameter value is less than the second parameter threshold. Wherein, the first parameter threshold is greater than the second parameter threshold, and the first target parameter value includes the amplitude of the flux linkage or the amplitude of the back electromotive force.

[0016] In one embodiment, when the first target parameter value includes the flux linkage amplitude, the input variable includes the flux linkage when the compressor speed is in a stable phase in a two-phase stationary coordinate system.

[0017] In this technical solution, under steady-state speed conditions, if the compressor is not faulty, the flux linkage amplitude of the compressor will be between the first parameter threshold and the second parameter threshold, i.e., stable between the first parameter threshold and the second parameter threshold. However, when the compressor is faulty, the flux linkage amplitude of the compressor will slowly increase or slowly decrease. Based on this, the flux linkage amplitude under steady-state speed conditions can be compared with the corresponding first parameter threshold and second parameter threshold to determine whether the compressor is faulty. In this technical solution, the corresponding diagnostic scheme can be selected according to the compressor's usage needs, improving the flexibility of fault diagnosis.

[0018] In any of the above technical solutions, when the first target parameter value includes the amplitude of the back electromotive force, the input variable includes: the back electromotive force when the compressor speed is in a stable phase in a two-phase rotating coordinate system.

[0019] In this technical solution, in a two-phase stationary coordinate system, the compressor fault can be determined based on the flux linkage amplitude. Based on this, in a two-phase rotating coordinate system, the compressor fault can also be diagnosed by using the back electromotive force amplitude. In this technical solution, the corresponding diagnostic scheme can be selected according to the compressor's usage needs, thus improving the flexibility of fault diagnosis.

[0020] In any of the above technical solutions, the following is also included: in the event of a compressor malfunction, outputting the cause of the malfunction, the cause of the malfunction including the decay of the magnetic properties of the permanent magnet.

[0021] In this technical solution, the cause of the abnormality is output so that the user can maintain the compressor according to the cause of the abnormality, thereby eliminating the compressor failure in a timely manner.

[0022] In any of the above technical solutions, when the target parameter value includes a second target parameter value, the diagnostic result of the compressor is determined based on the comparison result between the target parameter value and the corresponding parameter threshold. Specifically, this includes: if the cumulative number of times the second target parameter value is greater than the corresponding parameter threshold is greater than a preset number within a first time period, the compressor is abnormal; wherein, the second target parameter value includes a current difference or a speed difference.

[0023] In one of the technical solutions, when the second target parameter value includes the current difference, the current difference is the output value of the dq current controller when the given current value and the actual current value of the compressor are input to the dq current controller.

[0024] In one of the technical solutions, when the second target parameter value includes a speed difference, the speed difference is the output value of the speed controller when the given speed value and the actual speed value of the compressor are input to the speed controller.

[0025] In this process, the diagnostic results of the compressor are characterized by the judgment results in the statistical transient time domain over a period of time, thereby reducing the probability of misjudgment and improving the accuracy of compressor fault detection.

[0026] In any of the above technical solutions, the following is also included: in the event of a compressor malfunction, outputting the cause of the malfunction, the cause of the malfunction including the presence of decay in the compressor's mechanical components.

[0027] In the above technical solution, by outputting the cause of the abnormality, the user can maintain the compressor according to the cause of the abnormality, thereby eliminating the compressor failure in a timely manner.

[0028] In any of the above technical solutions, when the target parameter value includes a third target parameter value, the diagnostic result of the compressor is determined based on the comparison result between the target parameter value and the corresponding parameter threshold. Specifically, this includes: when the normalized fluctuation component is greater than the corresponding parameter threshold, the compressor is abnormal; wherein, the normalized fluctuation component is obtained by performing the following processing on the given speed value and the actual speed value of the compressor: determining the speed fluctuation component based on the given speed value and the actual speed value; determining the component of the speed fluctuation component at the mechanical speed; and normalizing the ratio of the component of the speed fluctuation component at the mechanical speed to the current amplitude of the compressor to obtain the normalized fluctuation component.

[0029] This technical solution defines how to determine the compressor's fault in the steady-state frequency domain. It provides possible diagnostic solutions for the compressor, allowing the selection of the appropriate diagnostic solution based on the compressor's usage requirements, thus improving the flexibility of fault diagnosis.

[0030] In any of the above technical solutions, when the target parameter value includes a third target parameter value, the diagnostic result of the compressor is determined based on the comparison result between the target parameter value and the corresponding parameter threshold. Specifically, this includes: if the phase difference is greater than the third parameter threshold or less than the fourth parameter threshold, the compressor is abnormal; wherein, the third parameter threshold is greater than the fourth parameter threshold, and the phase difference is obtained by processing the given speed value and the actual speed value of the compressor as follows: determining the speed fluctuation component based on the given speed value and the actual speed value; determining the phase difference between the current on the q-axis of the compressor and the fluctuation component in a two-phase rotating coordinate system.

[0031] In the above technical solution, the input variables include: the given speed value and the actual speed value of the compressor; the parameter thresholds include the third parameter threshold and the fourth parameter threshold, and the third parameter threshold is greater than the fourth parameter threshold.

[0032] In this technical solution, compressor fault identification can be performed based on the phase difference between the current and the fluctuation component on the q-axis. This technical solution provides possible diagnostic schemes for the compressor, and the corresponding diagnostic scheme can be selected according to the compressor's usage needs, thus improving the flexibility of fault diagnosis.

[0033] In any of the above technical solutions, the following is also included: in the event of a compressor malfunction, outputting the cause of the malfunction, the cause of the malfunction including non-uniform damage to the compressor's mechanical components.

[0034] In the above technical solution, by outputting the cause of the abnormality, the user can maintain the compressor according to the cause of the abnormality, thereby eliminating the compressor failure in a timely manner.

[0035] According to a second aspect of the present invention, a diagnostic device for a compressor is provided, wherein the compressor is associated with a compressor controller. The diagnostic device includes: an acquisition unit for acquiring input variables of the compressor controller; a processing unit for processing the input variables to obtain target parameter values, the target parameter values ​​including at least one of the following: a first target parameter value obtained by processing the input variables in the steady-state time domain, a second target parameter value obtained by processing the input variables in the transient time domain, and a third target parameter value obtained by processing the input variables in the steady-state frequency domain; and a diagnostic unit for determining a diagnostic result of the compressor based on a comparison result between the target parameter values ​​and corresponding parameter thresholds.

[0036] The technical solution of this application proposes a compressor diagnostic device that can detect compressor faults. In the above diagnostic process, the input variables input to the compressor controller are analyzed, processed, and judged to realize the compressor fault diagnosis. In this process, there is no need to perform spectrum analysis. Therefore, the amount of computation required for diagnosis is relatively small, thereby reducing the hardware requirements for compressor fault diagnosis.

[0037] In addition, the diagnostic device for the compressor proposed in this application has the following additional technical features.

[0038] In the above technical solution, the diagnostic unit is specifically used to: detect compressor malfunction when the first target parameter value is greater than the first parameter threshold or less than the second parameter threshold; wherein, the first parameter threshold is greater than the second parameter threshold, and the first target parameter value includes the amplitude of flux linkage or the amplitude of back electromotive force.

[0039] In one embodiment, when the first target parameter value includes the flux linkage amplitude, the input variable includes the flux linkage when the compressor speed is in a stable phase in a two-phase stationary coordinate system. In this technical solution, under steady-state speed conditions, if the compressor is not faulty, the compressor's flux linkage amplitude will be between the first parameter threshold and the second parameter threshold, i.e., stable between the first parameter threshold and the second parameter threshold. However, if the compressor is faulty, the compressor's flux linkage amplitude will slowly increase or slowly decrease. Based on this, the flux linkage amplitude under steady-state speed conditions can be compared with the corresponding first parameter threshold and second parameter threshold to determine whether the compressor is faulty. In this technical solution, a corresponding diagnostic scheme can be selected according to the compressor's usage needs, improving the flexibility of fault diagnosis.

[0040] In any of the above technical solutions, when the first target parameter value includes the amplitude of the back electromotive force, the input variable includes: the back electromotive force when the compressor speed is in a stable phase in a two-phase rotating coordinate system.

[0041] In this technical solution, in a two-phase stationary coordinate system, the compressor fault can be determined based on the flux linkage amplitude. Based on this, in a two-phase rotating coordinate system, the compressor fault can also be diagnosed by using the back electromotive force amplitude. In this technical solution, the corresponding diagnostic scheme can be selected according to the compressor's usage needs, thus improving the flexibility of fault diagnosis.

[0042] In any of the above technical solutions, the diagnostic unit is also used to: output the cause of the abnormality when the compressor is abnormal, including the decay of the magnetic properties of the permanent magnet.

[0043] In this technical solution, the cause of the abnormality is output so that the user can maintain the compressor according to the cause of the abnormality, thereby eliminating the compressor failure in a timely manner.

[0044] In any of the above technical solutions, the diagnostic unit is specifically used to: if, within a first time period, the cumulative number of times the second target parameter value is greater than the corresponding parameter threshold exceeds a preset number, the compressor malfunctions; wherein the second target parameter value includes a current difference or a speed difference. In one technical solution, when the second target parameter value includes a current difference, the current difference is the output value of the dq current controller when the given current value and the actual current value of the compressor are input to the dq current controller.

[0045] In one of the technical solutions, when the second target parameter value includes a speed difference, the speed difference is the output value of the speed controller when the given speed value and the actual speed value of the compressor are input to the speed controller.

[0046] In this process, the diagnostic results of the compressor are characterized by the judgment results in the statistical transient time domain over a period of time, thereby reducing the probability of misjudgment and improving the accuracy of compressor fault detection.

[0047] In any of the above technical solutions, the diagnostic unit is further configured to: output the cause of the abnormality in the event of a compressor malfunction, the cause of the abnormality including the presence of decay in the compressor's mechanical components.

[0048] In the above technical solution, by outputting the cause of the abnormality, the user can maintain the compressor according to the cause of the abnormality, thereby eliminating the compressor failure in a timely manner.

[0049] In any of the above technical solutions, the diagnostic unit is specifically used to: determine the compressor malfunction when the normalized fluctuation component is greater than the corresponding parameter threshold; wherein, the normalized fluctuation component is obtained by performing the following processing on the given speed value and the actual speed value of the compressor: determining the speed fluctuation component based on the given speed value and the actual speed value; determining the component of the speed fluctuation component at the mechanical speed; and normalizing the ratio of the component of the speed fluctuation component at the mechanical speed to the current amplitude of the compressor to obtain the normalized fluctuation component.

[0050] This technical solution defines how to determine the compressor's fault in the steady-state frequency domain. It provides possible diagnostic solutions for the compressor, allowing the selection of the appropriate diagnostic solution based on the compressor's usage requirements, thus improving the flexibility of fault diagnosis.

[0051] In any of the above technical solutions, the diagnostic unit is specifically used to: determine the compressor malfunction when the phase difference is greater than the third parameter threshold or less than the fourth parameter threshold; wherein, the third parameter threshold is greater than the fourth parameter threshold, and the phase difference is obtained by processing the given speed value and the actual speed value of the compressor as follows: determining the speed fluctuation component based on the given speed value and the actual speed value; determining the phase difference between the current on the q-axis of the compressor and the fluctuation component under two-phase rotating coordinates.

[0052] In the above technical solution, the input variables include: the given speed value and the actual speed value of the compressor; the parameter thresholds include the third parameter threshold and the fourth parameter threshold, and the third parameter threshold is greater than the fourth parameter threshold.

[0053] In this technical solution, compressor fault identification can be performed based on the phase difference between the current and the fluctuation component on the q-axis. This technical solution provides possible diagnostic schemes for the compressor, and the corresponding diagnostic scheme can be selected according to the compressor's usage needs, thus improving the flexibility of fault diagnosis.

[0054] In any of the above technical solutions, the diagnostic unit is further configured to: output the cause of the abnormality in the event of a compressor malfunction, the cause of the abnormality including the presence of non-uniform damage to the compressor's mechanical components.

[0055] In the above technical solution, by outputting the cause of the abnormality, the user can maintain the compressor according to the cause of the abnormality, thereby eliminating the compressor failure in a timely manner.

[0056] According to a third aspect of the present invention, the present invention provides a diagnostic device for a compressor, comprising: a controller and a memory, wherein the memory stores a program or instructions, and the controller, when executing the program or instructions in the memory, implements the steps of any of the diagnostic methods described above.

[0057] According to a fourth aspect of the present invention, a readable storage medium is provided on which a program or instructions are stored, which, when executed by a processor, implement the steps of any of the diagnostic methods described above.

[0058] According to a fifth aspect of the present invention, a compressor is provided, comprising: a diagnostic device for a compressor as described above; and / or a readable storage medium as described above.

[0059] According to a sixth aspect of the present invention, the present invention provides a vehicle comprising: a compressor as described in any of the above.

[0060] In the above technical solution, the vehicle also includes: an output device connected to the compressor, which outputs the cause of the abnormality based on the compressor's abnormality.

[0061] In this technical solution, the output device can be a sound output device, such as a speaker; it can also be a text display device, such as a display screen; or it can be a light output device, such as an indicator light.

[0062] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0063] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0064] Figure 1 One of the flowcharts of the compressor diagnostic method in an embodiment of the present invention is shown;

[0065] Figure 2 A second schematic flowchart of the compressor diagnostic method in an embodiment of the present invention is shown;

[0066] Figure 3 One of the schematic block diagrams of a compressor diagnostic device is shown in an embodiment of the present invention;

[0067] Figure 4 A second schematic block diagram of the diagnostic device for the compressor in an embodiment of the present invention is shown. Detailed Implementation

[0068] To better understand the above aspects, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0069] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0070] In one embodiment, a diagnostic method for a compressor is proposed, wherein the compressor is associated with a compressor controller, such as... Figure 1 As shown, the diagnostic methods include:

[0071] Step 102: Obtain the input variables of the compressor controller;

[0072] Step 104: Process the input variables to obtain target parameter values. The target parameter values ​​include at least one of the following: a first target parameter value obtained by processing the input variables in the steady-state time domain, a second target parameter value obtained by processing the input variables in the transient time domain, and a third target parameter value obtained by processing the input variables in the steady-state frequency domain.

[0073] Step 106: Determine the compressor's diagnostic result based on the comparison between the target parameter value and the corresponding parameter threshold.

[0074] The embodiments of this application propose a compressor diagnostic method. By running this diagnostic method, compressor fault detection can be achieved. In the above diagnostic method, the input variables input to the compressor controller are analyzed, processed, and judged to achieve compressor fault diagnosis. In this process, there is no need to perform spectrum analysis. Therefore, the amount of computation required for diagnosis is relatively small, thereby reducing the hardware requirements for compressor fault diagnosis.

[0075] The compressor controller is a device used to maintain the pipeline pressure within a set limit range. The compressor controller maintains the pipeline pressure within the set limit range by automatically loading and unloading the compressor.

[0076] The input variables include the compressor's operating variables and / or control variables. The operating variables can be understood as variables that reflect the compressor's operating status during operation, such as the compressor's actual speed, three-phase current value, bus voltage, etc.

[0077] In one embodiment, the control variable can be understood as a variable used to control the operation of the compressor, such as a given speed value, a given current value, etc.

[0078] The embodiments of this application are based on the following principle: Specifically, when the compressor is not faulty, the target parameter value obtained based on the input variables will be within a reasonable range. However, when the compressor is faulty, the compressor's operating conditions will change, and the compressor fault will be represented by the input variables. At this time, the input variables input to the compressor controller are collected and analyzed to obtain the target parameter value. The compressor fault is reflected in the target parameter value, and the target parameter value is compared with the corresponding parameter threshold. The parameter threshold is used to characterize whether the target parameter value exceeds a reasonable range, thereby realizing the diagnosis of whether the compressor is faulty.

[0079] In one embodiment, if it is determined that the compressor is not faulty, input variables are continuously acquired to enable continuous diagnosis of whether the compressor is faulty. This allows for timely maintenance in case of compressor failure, thereby reducing the impact of the compressor failure.

[0080] In one embodiment, maintenance includes, but is not limited to, remagnetizing, replacing structural components of the compressor, and adjusting the power supply to the compressor.

[0081] In the above embodiments, when the target parameter value includes a first target parameter value, the diagnostic result of the compressor is determined based on the comparison result between the target parameter value and the corresponding parameter threshold. Specifically, the compressor is abnormal when the first target parameter value is greater than the first parameter threshold or when the first target parameter value is less than the second parameter threshold. Wherein, the first parameter threshold is greater than the second parameter threshold, and the first target parameter value includes the amplitude of the flux linkage or the amplitude of the back electromotive force.

[0082] In one embodiment, when the first target parameter value includes the flux linkage amplitude, the input variable includes the flux linkage when the compressor speed is in a stable phase in a two-phase stationary coordinate system.

[0083] Specifically, the input variables include: the flux linkage when the compressor speed is in a stable phase in a two-phase stationary coordinate system; the parameter thresholds include a first parameter threshold and a second parameter threshold, wherein the first parameter threshold is greater than the second parameter threshold; and determining the first target parameter value obtained by processing the input variables in the steady-state time domain, specifically including: determining the flux linkage amplitude based on the flux linkage.

[0084] In this embodiment, under steady-state speed conditions, if the compressor is not faulty, the flux linkage amplitude of the compressor will be between the first parameter threshold and the second parameter threshold, that is, stable between the first parameter threshold and the second parameter threshold. However, if the compressor is faulty, the flux linkage amplitude of the compressor will slowly increase or slowly decrease. Based on this, the flux linkage amplitude under steady-state speed conditions can be compared with the corresponding first parameter threshold and second parameter threshold to determine whether the compressor is faulty. In this embodiment, the corresponding diagnostic scheme can be selected according to the usage needs of the compressor, which improves the flexibility of fault diagnosis.

[0085] Steady state, in this context, refers to the state of the system maintained when all input variables remain constant after all transient effects have disappeared. Based on this, speed steady state, which is the state of the compressor when its speed remains constant, can be understood as the state under a fixed load when the compressor speed reaches the inverter's set speed and operates stably.

[0086] In the steady-state time domain, the magnetic flux of the compressor is obtained, and the magnetic flux amplitude is determined based on the magnetic flux, which overcomes the influence of all transient effects and improves the accuracy of judging whether the compressor is faulty.

[0087] In the above embodiment, in the two-phase stationary coordinate system, the magnetic flux of the compressor includes λd and λq, and the magnetic flux amplitude is obtained by processing λd and λq.

[0088] In one embodiment, the first parameter threshold and the second parameter threshold are parameter thresholds under steady-state rotational speed.

[0089] In this embodiment, by limiting the first parameter threshold and the second parameter threshold to parameter thresholds under steady-state speed, both sides of the comparison, namely the first parameter threshold, the second parameter threshold, and the flux linkage amplitude, are under steady-state speed, thereby improving the accuracy of compressor fault detection.

[0090] In one embodiment, when the first target parameter value includes the magnitude of the back EMF, the input variable includes the back EMF when the compressor speed is in a stable phase in a two-phase rotating coordinate system.

[0091] Specifically, the input variables include: the back electromotive force when the compressor speed is in a stable phase under a two-phase rotating coordinate system; and the determination of the first target parameter value obtained by processing the input variables in the steady-state time domain, specifically including: determining the amplitude of the back electromotive force based on the back electromotive force.

[0092] In this embodiment, in a two-phase stationary coordinate system, the compressor fault can be determined based on the flux linkage amplitude. Based on this, in a two-phase rotating coordinate system, the compressor fault can also be diagnosed by using the back electromotive force amplitude. In this embodiment, the corresponding diagnostic scheme can be selected according to the compressor's usage needs, thus improving the flexibility of fault diagnosis.

[0093] Specifically, if the compressor is not faulty, the amplitude of the compressor's back EMF is between the first parameter threshold and the second parameter threshold, that is, it is stable between the first parameter threshold and the second parameter threshold. However, if the compressor is faulty, the amplitude of the compressor's back EMF will slowly increase or slowly decrease. Based on this, the amplitude of the back EMF under steady-state speed can be compared with the corresponding first parameter threshold and second parameter threshold to determine whether the compressor is faulty.

[0094] In the steady-state time domain, the amplitude of the compressor's back electromotive force is determined, overcoming the influence of all transient effects and improving the accuracy of judging whether the compressor is faulty.

[0095] In the above embodiment, the ed and eq of the compressor are obtained in a two-phase rotating coordinate system, and the amplitude of the back electromotive force is obtained by processing the ed and eq.

[0096] In one embodiment, the first parameter threshold and the second parameter threshold are parameter thresholds under steady-state rotational speed.

[0097] In this embodiment, by limiting the first parameter threshold and the second parameter threshold to parameter thresholds under steady-state speed, both sides of the comparison, namely the first parameter threshold, the second parameter threshold, and the amplitude of the back EMF, are under steady-state speed, thereby improving the accuracy of compressor fault detection.

[0098] In any of the above embodiments, the method further includes: in the event of a compressor malfunction, outputting a cause of the malfunction, the cause of the malfunction including the decay of the magnetic properties of the permanent magnet.

[0099] In this embodiment, by outputting the cause of the abnormality, the user can perform maintenance on the compressor based on the cause of the abnormality, thereby promptly eliminating compressor malfunctions.

[0100] Permanent magnets are magnets that can retain a high remanence for a long time in an open-circuit state. Based on this, magnetic properties decay, meaning the remanence in a permanent magnet decreases compared to before.

[0101] In one embodiment, the target parameter value is determined to be independent of the time parameter. It is understood that the target parameter value does not change with the duration. By selecting the above target parameter value, long-term fault monitoring can be achieved when diagnosing compressor faults.

[0102] In one embodiment, the target parameter value is determined to be independent of the compressor's operating conditions. It is understood that the target parameter value does not change with changes in operating conditions. By selecting the above target parameter value, long-term fault monitoring can be achieved when diagnosing compressor faults.

[0103] In any of the above embodiments, when the target parameter value includes a second target parameter value, the diagnostic result of the compressor is determined based on the comparison result between the target parameter value and the corresponding parameter threshold. Specifically, this includes: if the cumulative number of times the second target parameter value is greater than the corresponding parameter threshold is greater than a preset number within a first time period, the compressor is abnormal; wherein, the second target parameter value includes a current difference or a speed difference.

[0104] In one embodiment, when the second target parameter value includes a current difference, the current difference is the output value of the dq current controller when the given current value and the actual current value of the compressor are input to the dq current controller.

[0105] In one embodiment, when the second target parameter value includes a speed difference, the speed difference is the output value of the speed controller when the given speed value and the actual speed value of the compressor are input to the speed controller.

[0106] In the case where the second target parameter value includes the current difference, the input variables include: the given current value and the detected actual current value.

[0107] When the second target parameter value includes the speed difference, the input variables include: the given speed value and the detected actual speed value.

[0108] This embodiment presents a solution for diagnosing compressor faults in the transient time domain.

[0109] Specifically, if the compressor is functioning correctly, the current difference output by the dq current controller will fluctuate within a certain range. Similarly, the speed difference output by the speed controller will also fluctuate within the same range. However, if the compressor malfunctions, these current and speed differences may suddenly increase or decrease. Here, the current difference refers to the difference between a given current value and the actual current value, and the speed difference refers to the difference between a given speed value and the actual speed value. Based on this, the determined current and / or speed differences can be compared with corresponding parameter thresholds to determine if there are sudden changes in the current or speed differences, thus indicating whether the compressor is malfunctioning.

[0110] Considering that the above diagnostic results are obtained in the transient time domain, if only a single comparison result is used as the diagnostic result of whether the compressor is faulty, misjudgment is very likely to occur. In order to avoid the occurrence of the above misjudgment, the embodiments of this application specifically limit the determination of compressor faulty only when the cumulative number of times the current difference is greater than the corresponding parameter threshold exceeds a preset number within the first time period.

[0111] Similarly, within the first time period, the compressor can only be determined to be faulty if the cumulative number of times the speed difference is greater than the corresponding parameter threshold exceeds the preset number.

[0112] In this process, the diagnostic results of the compressor are characterized by the judgment results in the statistical transient time domain over a period of time, thereby reducing the probability of misjudgment and improving the accuracy of compressor fault detection.

[0113] In one embodiment, the first duration can be determined based on the detection accuracy of whether the compressor is faulty. Specifically, the detection accuracy is positively correlated with the first duration. That is, as the detection accuracy increases, the value of the first duration increases, and conversely, as the detection accuracy decreases, the value of the first duration decreases.

[0114] In one embodiment, the preset number of times can be set according to actual usage needs. Specifically, when the interval between single fault detections is fixed, the preset number of times is less than the ratio of the first duration to the interval duration.

[0115] In one embodiment, the value of the preset number of times is positively correlated with the detection accuracy of whether the compressor is faulty. That is, as the detection accuracy increases, the value of the preset number of times increases, and vice versa, as the detection accuracy decreases, the value of the preset number of times decreases.

[0116] In any of the above embodiments, the method further includes: in the event of a compressor malfunction, outputting a cause of the malfunction, the cause of the malfunction including the presence of decay in the compressor's mechanical components.

[0117] In the above embodiments, by outputting the cause of the abnormality, the user can maintain the compressor according to the cause of the abnormality, thereby eliminating the compressor failure in a timely manner.

[0118] The mechanical components include, for example, the pump body and bearings of a compressor. Therefore, the decay of these components can be understood as wear and tear. Specifically, this wear can be the wear of the pump body, the wear of the bearings, etc., and it is a type of uniform wear.

[0119] In any of the above embodiments, when the target parameter value includes a third target parameter value, the diagnostic result of the compressor is determined based on the comparison result between the target parameter value and the corresponding parameter threshold. Specifically, this includes: when the normalized fluctuation component is greater than the corresponding parameter threshold, the compressor is abnormal; wherein, the normalized fluctuation component is obtained by performing the following processing on the given speed value and the actual speed value of the compressor: determining the speed fluctuation component based on the given speed value and the actual speed value; determining the component of the speed fluctuation component at the mechanical speed; and normalizing the ratio of the component of the speed fluctuation component at the mechanical speed to the current amplitude of the compressor to obtain the normalized fluctuation component.

[0120] In the above embodiments, the input variables include: the given speed value and the actual speed value of the compressor, and the third target parameter value, which is the normalized fluctuation component mentioned above.

[0121] In this embodiment, a scheme for determining whether the compressor has a fault is defined in the steady-state frequency domain. In this embodiment, possible diagnostic schemes for the compressor are provided, and the corresponding diagnostic scheme can be selected according to the usage needs of the compressor, thereby improving the flexibility of fault diagnosis.

[0122] In the above embodiments, the fluctuation component of the rotational speed can be understood as the difference between the given rotational speed value and the actual rotational speed value.

[0123] In the above embodiments, the mechanical speed is determined based on the structural characteristics of the compressor. Specifically, in the case of a synchronous compressor, the synchronous speed and the mechanical speed are in a fixed proportional relationship. This ratio equals the number of actual load fluctuations per revolution of the compressor. Taking a turbo compressor or a single-cylinder reciprocating compressor as an example, with one intake and exhaust cycle per load period, the ratio is 1:1, then ωmech = ω1, where ωmech is the mechanical speed and ω1 is the synchronous compressor speed.

[0124] For a twin-cylinder rotary compressor, the ratio is 2:1, then ωmech = 2 × ω1.

[0125] An adaptive bandpass filter can be used to process the rotational speed fluctuation component to obtain the component of the rotational speed fluctuation component at the mechanical speed. The adaptive bandpass filter can be a second-order generalized integrator (SOGI) or an adaptive linear element (ADLINE). The center frequency of the adaptive bandpass filter is ωmech.

[0126] By comparing the current amplitude with that of the compressor and normalizing the ratio, the normalized fluctuation component can be compared with the parameter threshold (which can be understood as a preset fluctuation component threshold) to determine whether the compressor is faulty.

[0127] In the above embodiments, the current amplitude can be calculated using iα and iβ in a two-phase stationary coordinate system, or it can be obtained using the square roots of id and iq in a two-phase rotating coordinate system.

[0128] In any of the above embodiments, when the target parameter value includes a third target parameter value, the diagnostic result of the compressor is determined based on the comparison result between the target parameter value and the corresponding parameter threshold. Specifically, this includes: if the phase difference is greater than the third parameter threshold or less than the fourth parameter threshold, the compressor is abnormal; wherein, the third parameter threshold is greater than the fourth parameter threshold, and the phase difference is obtained by processing the given speed value and the actual speed value of the compressor as follows: determining the speed fluctuation component based on the given speed value and the actual speed value; determining the phase difference between the current on the q-axis of the compressor and the fluctuation component in a two-phase rotating coordinate system.

[0129] The input variables include the given speed value and the actual speed value of the compressor, where the third target parameter value is the phase difference mentioned above.

[0130] In this embodiment, compressor fault identification can be performed based on the phase difference between the current and the fluctuation component on the q-axis. This embodiment provides possible diagnostic solutions for the compressor, and the corresponding diagnostic solution can be selected according to the compressor's usage needs, thus improving the flexibility of fault diagnosis.

[0131] Specifically, iq is related to the motor's output torque, and Δω is the result of the combined effect of the motor's output torque and the load torque. The phase difference between them reflects the changes in load characteristics.

[0132] The phase difference can be calculated using techniques such as phase-locked loops.

[0133] Specifically, when the compressor is not faulty, the phase difference will be between the third parameter threshold and the fourth parameter threshold, that is, it will be stable between the third parameter threshold and the fourth parameter threshold. However, when the compressor is faulty, the phase difference will slowly increase or slowly decrease. Based on this, the phase difference can be compared with the corresponding third parameter threshold and the fourth parameter threshold to determine whether the compressor is faulty. In this embodiment, the corresponding diagnostic scheme can be selected according to the usage needs of the compressor, which improves the flexibility of fault diagnosis.

[0134] In any of the above embodiments, the method further includes: in the event of a compressor malfunction, outputting the cause of the malfunction, the cause of the malfunction including non-uniform damage to the compressor's mechanical components.

[0135] In the above embodiments, by outputting the cause of the abnormality, the user can maintain the compressor according to the cause of the abnormality, thereby eliminating the compressor failure in a timely manner.

[0136] Non-uniform damage can be understood as damage to the pump body, damage to the bearing, etc., and the aforementioned damage belongs to non-uniform damage.

[0137] In any of the above embodiments, the input variables may further include: current iα, iβ, voltage uα, uβ, flux linkage λα, λβ, back electromotive force eα, eβ, and given rotational speed value ωref. The above input variables are related to the coordinate system, such as the three-phase stationary coordinate system abc, the two-phase stationary coordinate system αβ, and the two-phase rotating coordinate system dq. The above input variables can still be applied to the technical embodiments of this application after the coordinate system is transformed.

[0138] In one embodiment, the input variables may further include: the actual rotational speed ωr, the synchronous electrical angle θ, and the synchronous frequency ω1. The above input variables are independent of the coordinate system, and therefore can be selected according to the actual application scenario.

[0139] In one embodiment, such as Figure 2 As shown, the diagnostic methods for compressors include:

[0140] Step 202: Receive input variables from the compressor controller;

[0141] Step 204: Perform the fault determination steps in the steady-state time domain;

[0142] Step 206: Perform the fault determination steps in the transient time domain;

[0143] Step 208: Perform the fault determination steps in the steady-state frequency domain;

[0144] Step 210, Fault Synthesis;

[0145] Step 212, fault output.

[0146] In one embodiment, such as Figure 3 As shown, the present invention provides a compressor diagnostic device 300. The compressor is associated with a compressor controller. The diagnostic device includes: an acquisition unit 302 for acquiring input variables of the compressor controller; a processing unit 304 for processing the input variables to obtain target parameter values, the target parameter values ​​including at least one of the following: a first target parameter value obtained by processing the input variables in the steady-state time domain, a second target parameter value obtained by processing the input variables in the transient time domain, and a third target parameter value obtained by processing the input variables in the steady-state frequency domain; and a diagnostic unit 306 for determining the diagnostic result of the compressor based on the comparison result of the target parameter value and the corresponding parameter threshold.

[0147] The embodiments of this application propose a compressor diagnostic device 300, which can realize compressor fault detection. In the above diagnostic process, the input variables input to the compressor controller are analyzed, processed and judged to realize compressor fault diagnosis. In this process, there is no need to perform spectrum analysis. Therefore, the amount of computation required for diagnosis is relatively small, thereby reducing the hardware requirements for compressor fault diagnosis.

[0148] The compressor controller is a device used to maintain the pipeline pressure within a set limit range. The compressor controller maintains the pipeline pressure within the set limit range by automatically loading and unloading the compressor.

[0149] Among them, operating variables can be understood as variables that reflect the operating status of the compressor during operation, such as the actual speed of the compressor, the three-phase current value, and the bus voltage.

[0150] In one embodiment, the control variable can be understood as a variable used to control the operation of the compressor, such as a given speed value, a given current value, etc.

[0151] The embodiments of this application are based on the following principle: Specifically, when the compressor is not faulty, the target parameter value obtained based on the input variables will be within a reasonable range. However, when the compressor is faulty, the compressor's operating conditions will change, and the compressor fault will be represented by the input variables. At this time, the input variables input to the compressor controller are collected and analyzed to obtain the target parameter value. The compressor fault is reflected in the target parameter value, and the target parameter value is compared with the corresponding parameter threshold. The parameter threshold is used to characterize whether the target parameter value exceeds a reasonable range, thereby realizing the diagnosis of whether the compressor is faulty.

[0152] In one embodiment, if it is determined that the compressor is not faulty, input variables are continuously acquired to enable continuous diagnosis of whether the compressor is faulty. This allows for timely maintenance in case of compressor failure, thereby reducing the impact of the compressor failure.

[0153] In one embodiment, maintenance includes, but is not limited to, remagnetizing, replacing structural components of the compressor, and adjusting the power supply to the compressor.

[0154] In the above embodiment, the diagnostic unit 306 is specifically used to: cause a compressor malfunction when the first target parameter value is greater than the first parameter threshold or the first target parameter value is less than the second parameter threshold; wherein, the first parameter threshold is greater than the second parameter threshold, and the first target parameter value includes the amplitude of the flux linkage or the amplitude of the back electromotive force.

[0155] In one embodiment, when the first target parameter value includes the flux linkage amplitude, the input variable includes the flux linkage when the compressor speed is in a stable phase in a two-phase stationary coordinate system.

[0156] In this embodiment, under steady-state speed conditions, if the compressor is not faulty, the flux linkage amplitude of the compressor will be between the first parameter threshold and the second parameter threshold, that is, stable between the first parameter threshold and the second parameter threshold. However, if the compressor is faulty, the flux linkage amplitude of the compressor will slowly increase or slowly decrease. Based on this, the flux linkage amplitude under steady-state speed conditions can be compared with the corresponding first parameter threshold and second parameter threshold to determine whether the compressor is faulty. In this embodiment, the corresponding diagnostic scheme can be selected according to the usage needs of the compressor, which improves the flexibility of fault diagnosis.

[0157] Steady state, in this context, refers to the state of the system maintained when all input variables remain constant after all transient effects have disappeared. Based on this, speed steady state, which is the state of the compressor when its speed remains constant, can be understood as the state under a fixed load when the compressor speed reaches the inverter's set speed and operates stably.

[0158] In the steady-state time domain, the magnetic flux of the compressor is obtained, and the magnetic flux amplitude is determined based on the magnetic flux, which overcomes the influence of all transient effects and improves the accuracy of judging whether the compressor is faulty.

[0159] In the above embodiment, in the two-phase stationary coordinate system, the magnetic flux of the compressor includes λd and λq, and the magnetic flux amplitude is obtained by processing λd and λq.

[0160] In one embodiment, the first parameter threshold and the second parameter threshold are parameter thresholds under steady-state rotational speed.

[0161] In this embodiment, by limiting the first parameter threshold and the second parameter threshold to parameter thresholds under steady-state speed, both sides of the comparison, namely the first parameter threshold, the second parameter threshold, and the flux linkage amplitude, are under steady-state speed, thereby improving the accuracy of compressor fault detection.

[0162] In any of the above embodiments, when the first target parameter value includes the amplitude of the back EMF, the input variable includes: the back EMF when the compressor speed is in a stable phase in a two-phase rotating coordinate system.

[0163] In this embodiment, in a two-phase stationary coordinate system, the compressor fault can be determined based on the flux linkage amplitude. Based on this, in a two-phase rotating coordinate system, the compressor fault can also be diagnosed by using the back electromotive force amplitude. In this embodiment, the corresponding diagnostic scheme can be selected according to the compressor's usage needs, thus improving the flexibility of fault diagnosis.

[0164] Specifically, if the compressor is not faulty, the amplitude of the compressor's back EMF is between the first parameter threshold and the second parameter threshold, that is, it is stable between the first parameter threshold and the second parameter threshold. However, if the compressor is faulty, the amplitude of the compressor's back EMF will slowly increase or slowly decrease. Based on this, the amplitude of the back EMF under steady-state speed can be compared with the corresponding first parameter threshold and second parameter threshold to determine whether the compressor is faulty.

[0165] In the steady-state time domain, the amplitude of the compressor's back electromotive force is determined, overcoming the influence of all transient effects and improving the accuracy of judging whether the compressor is faulty.

[0166] In the above embodiment, the ed and eq of the compressor are obtained in a two-phase rotating coordinate system, and the amplitude of the back electromotive force is obtained by processing the ed and eq.

[0167] In one embodiment, the first parameter threshold and the second parameter threshold are parameter thresholds under steady-state rotational speed.

[0168] In this embodiment, by limiting the first parameter threshold and the second parameter threshold to parameter thresholds under steady-state speed, both sides of the comparison, namely the first parameter threshold, the second parameter threshold, and the amplitude of the back EMF, are under steady-state speed, thereby improving the accuracy of compressor fault detection.

[0169] In any of the above embodiments, the diagnostic unit 306 is further configured to: output the cause of the abnormality in the event of a compressor malfunction, the cause of the abnormality including the decay of the magnetic properties of the permanent magnet.

[0170] In this embodiment, by outputting the cause of the abnormality, the user can perform maintenance on the compressor based on the cause of the abnormality, thereby promptly eliminating compressor malfunctions.

[0171] Permanent magnets are magnets that can retain a high remanence for a long time in an open-circuit state. Based on this, magnetic properties decay, meaning the remanence in a permanent magnet decreases compared to before.

[0172] In one embodiment, the target parameter value is determined to be independent of the time parameter. It is understood that the target parameter value does not change with the duration. By selecting the above target parameter value, long-term fault monitoring can be achieved when diagnosing compressor faults.

[0173] In one embodiment, the target parameter value is determined to be independent of the compressor's operating conditions. It is understood that the target parameter value does not change with changes in operating conditions. By selecting the above target parameter value, long-term fault monitoring can be achieved when diagnosing compressor faults.

[0174] In any of the above embodiments, the diagnostic unit 306 is specifically used to: when the cumulative number of times the second target parameter value is greater than the corresponding parameter threshold is greater than a preset number within a first time period, the compressor is abnormal; wherein, the second target parameter value includes current difference or speed difference.

[0175] In one embodiment, when the second target parameter value includes a current difference, the current difference is the output value of the dq current controller when the given current value and the actual current value of the compressor are input to the dq current controller.

[0176] In one embodiment, when the second target parameter value includes a speed difference, the speed difference is the output value of the speed controller when the given speed value and the actual speed value of the compressor are input to the speed controller.

[0177] This embodiment presents a solution for diagnosing compressor faults in the transient time domain.

[0178] Specifically, if the compressor is functioning correctly, the current difference output by the dq current controller will fluctuate within a certain range. Similarly, the speed difference output by the speed controller will also fluctuate within the same range. However, if the compressor malfunctions, these current and speed differences may suddenly increase or decrease. Here, the current difference refers to the difference between a given current value and the actual current value, and the speed difference refers to the difference between a given speed value and the actual speed value. Based on this, the determined current and / or speed differences can be compared with corresponding parameter thresholds to determine if there are sudden changes in the current or speed differences, thus indicating whether the compressor is malfunctioning.

[0179] Considering that the above diagnostic results are obtained in the transient time domain, if only a single comparison result is used as the diagnostic result of whether the compressor is faulty, misjudgment is very likely to occur. In order to avoid the occurrence of the above misjudgment, the embodiments of this application specifically limit the determination of compressor faulty only when the cumulative number of times the current difference is greater than the corresponding parameter threshold exceeds a preset number within the first time period.

[0180] Similarly, within the first time period, the compressor can only be determined to be faulty if the cumulative number of times the speed difference is greater than the corresponding parameter threshold exceeds the preset number.

[0181] In this process, the diagnostic results of the compressor are characterized by the judgment results in the statistical transient time domain over a period of time, thereby reducing the probability of misjudgment and improving the accuracy of compressor fault detection.

[0182] In one embodiment, the first duration can be determined based on the detection accuracy of whether the compressor is faulty. Specifically, the detection accuracy is positively correlated with the first duration. That is, as the detection accuracy increases, the value of the first duration increases, and conversely, as the detection accuracy decreases, the value of the first duration decreases.

[0183] In one embodiment, the preset number of times can be set according to actual usage needs. Specifically, when the interval between single fault detections is fixed, the preset number of times is less than the ratio of the first duration to the interval duration.

[0184] In one embodiment, the value of the preset number of times is positively correlated with the detection accuracy of whether the compressor is faulty. That is, as the detection accuracy increases, the value of the preset number of times increases, and vice versa, as the detection accuracy decreases, the value of the preset number of times decreases.

[0185] In any of the above embodiments, the diagnostic unit 306 is further configured to: output the cause of the abnormality in the event of a compressor malfunction, the cause of the abnormality including the presence of decay in the compressor's mechanical components.

[0186] In the above embodiments, by outputting the cause of the abnormality, the user can maintain the compressor according to the cause of the abnormality, thereby eliminating the compressor failure in a timely manner.

[0187] The mechanical components include, for example, the pump body and bearings of a compressor. Therefore, the decay of these components can be understood as wear and tear. Specifically, this wear can be the wear of the pump body, the wear of the bearings, etc., and it is a type of uniform wear.

[0188] In any of the above embodiments, the diagnostic unit 306 is specifically used to: determine the compressor malfunction when the normalized fluctuation component is greater than the corresponding parameter threshold; wherein, the normalized fluctuation component is obtained by performing the following processing on the given speed value and the actual speed value of the compressor: determining the speed fluctuation component based on the given speed value and the actual speed value; determining the component of the speed fluctuation component at the mechanical speed; and normalizing the ratio of the component of the speed fluctuation component at the mechanical speed to the current amplitude of the compressor to obtain the normalized fluctuation component.

[0189] In this embodiment, a scheme for determining whether the compressor has a fault is defined in the steady-state frequency domain. In this embodiment, possible diagnostic schemes for the compressor are provided, and the corresponding diagnostic scheme can be selected according to the usage needs of the compressor, thereby improving the flexibility of fault diagnosis.

[0190] In the above embodiments, the fluctuation component of the rotational speed can be understood as the difference between the given rotational speed value and the actual rotational speed value.

[0191] In the above embodiments, the mechanical speed is determined based on the structural characteristics of the compressor. Specifically, in the case of a synchronous compressor, the synchronous speed and the mechanical speed are in a fixed proportional relationship. This ratio equals the number of actual load fluctuations per revolution of the compressor. Taking a turbo compressor or a single-cylinder reciprocating compressor as an example, with one intake and exhaust cycle per load period, the ratio is 1:1, then ωmech = ω1, where ωmech is the mechanical speed and ω1 is the synchronous compressor speed.

[0192] For a twin-cylinder rotary compressor, the ratio is 2:1, then ωmech = 2 × ω1.

[0193] An adaptive bandpass filter can be used to process the rotational speed fluctuation component to obtain the component of the rotational speed fluctuation component at the mechanical speed. The adaptive bandpass filter can be a second-order generalized integrator (SOGI) or an adaptive linear element (ADLINE). The center frequency of the adaptive bandpass filter is ωmech.

[0194] By comparing the current amplitude with that of the compressor and normalizing the ratio, the normalized fluctuation component can be compared with the parameter threshold (which can be understood as a preset fluctuation component threshold) to determine whether the compressor is faulty.

[0195] In the above embodiments, the current amplitude can be calculated using iα and iβ in a two-phase stationary coordinate system, or it can be obtained using the square roots of id and iq in a two-phase rotating coordinate system.

[0196] In any of the above embodiments, the diagnostic unit 306 is specifically used to: determine the compressor malfunction when the phase difference is greater than the third parameter threshold or less than the fourth parameter threshold; wherein the third parameter threshold is greater than the fourth parameter threshold, and the phase difference is obtained by processing the given speed value and the actual speed value of the compressor as follows: determining the speed fluctuation component based on the given speed value and the actual speed value; determining the phase difference between the current on the q-axis of the compressor and the fluctuation component under two-phase rotating coordinates.

[0197] In this embodiment, compressor fault identification can be performed based on the phase difference between the current and the fluctuation component on the q-axis. This embodiment provides possible diagnostic solutions for the compressor, and the corresponding diagnostic solution can be selected according to the compressor's usage needs, thus improving the flexibility of fault diagnosis.

[0198] Specifically, iq is related to the motor's output torque, and Δω is the result of the combined effect of the motor's output torque and the load torque. The phase difference between them reflects the changes in load characteristics.

[0199] The phase difference can be calculated using techniques such as phase-locked loops.

[0200] Specifically, when the compressor is not faulty, the phase difference will be between the third parameter threshold and the fourth parameter threshold, that is, it will be stable between the third parameter threshold and the fourth parameter threshold. However, when the compressor is faulty, the phase difference will slowly increase or slowly decrease. Based on this, the phase difference can be compared with the corresponding third parameter threshold and the fourth parameter threshold to determine whether the compressor is faulty. In this embodiment, the corresponding diagnostic scheme can be selected according to the usage needs of the compressor, which improves the flexibility of fault diagnosis.

[0201] In any of the above embodiments, the diagnostic unit 306 is further configured to: output the cause of the abnormality in the event of a compressor malfunction, the cause of the abnormality including the presence of non-uniform damage to the compressor's mechanical components.

[0202] In the above embodiments, by outputting the cause of the abnormality, the user can maintain the compressor according to the cause of the abnormality, thereby eliminating the compressor failure in a timely manner.

[0203] Non-uniform damage can be understood as damage to the pump body, damage to the bearing, etc., and the aforementioned damage belongs to non-uniform damage.

[0204] In any of the above embodiments, the input variables may further include: current iα, iβ, voltage uα, uβ, flux linkage λα, λβ, back electromotive force eα, eβ, and given rotational speed value ωref. The above input variables are related to the coordinate system, such as the three-phase stationary coordinate system abc, the two-phase stationary coordinate system αβ, and the two-phase rotating coordinate system dq. The above input variables can still be applied to the technical embodiments of this application after the coordinate system is transformed.

[0205] In one embodiment, the input variables may further include: the actual rotational speed ωr, the synchronous electrical angle θ, and the synchronous frequency ω1. The above input variables are independent of the coordinate system, and therefore can be selected according to the actual application scenario.

[0206] In one embodiment, such as Figure 4 As shown, the present invention provides a diagnostic device 400 for a compressor, comprising: a controller 402 and a memory 404, wherein the memory 404 stores a program or instructions, and the controller 402 implements the steps of any of the diagnostic methods described above when executing the program or instructions in the memory 404.

[0207] The memory 404 can be used to store software programs and various data. The memory may primarily include a first storage area for storing programs or instructions and a second storage area for storing data. The first storage area may store the operating system, application programs or instructions required for at least one function (such as sound playback, image playback, etc.). Furthermore, the memory may include volatile memory or non-volatile memory, or both. The non-volatile memory may be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. Volatile memory can be random access memory (RAM), static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDRSDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous linked dynamic random access memory (SLDRAM), and direct memory bus RAM (DRRAM). The memory in the embodiments of this application includes, but is not limited to, these and any other suitable types of memory.

[0208] In one embodiment, the present invention provides a readable storage medium on which a program or instructions are stored, which, when executed by a processor, implement the steps of any of the diagnostic methods described above.

[0209] When the program or instructions stored in the readable storage medium proposed in this application are executed, they can implement the above-mentioned diagnostic method. Therefore, when the program or instructions stored in the readable storage medium are executed, they have all the technical effects of the above-mentioned embodiments, which will not be repeated here.

[0210] In one embodiment, the present invention provides a compressor, including: a diagnostic device for a compressor as described above; and / or a readable storage medium as described above.

[0211] The embodiments of this application propose a compressor that can realize compressor fault detection. Specifically, it realizes compressor fault diagnosis by analyzing, processing and judging the input variables input to the compressor controller. In this process, there is no need to perform spectrum analysis. Therefore, the amount of computation required for diagnosis is relatively small, thereby reducing the hardware requirements for compressor fault diagnosis.

[0212] The compressor controller is a device used to maintain the pipeline pressure within a set limit range. The compressor controller maintains the pipeline pressure within the set limit range by automatically loading and unloading the compressor.

[0213] Among them, operating variables can be understood as variables that reflect the operating status of the compressor during operation, such as the actual speed of the compressor, the three-phase current value, and the bus voltage.

[0214] In one embodiment, the control variable can be understood as a variable used to control the operation of the compressor, such as a given speed value, a given current value, etc.

[0215] The embodiments of this application are based on the following principle: Specifically, when the compressor is not faulty, the target parameter value obtained based on the input variables will be within a reasonable range. However, when the compressor is faulty, the operating conditions of the compressor will change, and the compressor fault will be represented in the form of input variables. At this time, the input variables input to the compressor controller are collected and analyzed to obtain the target parameter value. The compressor fault is reflected in the target parameter value, and the target parameter value is compared with the corresponding parameter threshold. The parameter threshold is used to characterize whether the target parameter value exceeds a reasonable range, thereby realizing the diagnosis of whether the compressor is faulty.

[0216] In one embodiment, if it is determined that the compressor is not faulty, input variables are continuously acquired to enable continuous diagnosis of whether the compressor is faulty. This allows for timely maintenance in case of compressor failure, thereby reducing the impact of the compressor failure.

[0217] In one embodiment, maintenance includes, but is not limited to, remagnetizing, replacing structural components of the compressor, and adjusting the power supply to the compressor.

[0218] In one embodiment, the compressor is an electric compressor.

[0219] In one embodiment, the present invention provides a vehicle including a compressor as described above.

[0220] In the above embodiment, the vehicle further includes: an output device connected to the compressor, which outputs the cause of the malfunction based on the compressor malfunction.

[0221] In this embodiment, the output device can be a sound output device, such as a speaker; it can also be a text display device, such as a display screen; or it can be a light output device, such as an indicator light.

[0222] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the textual description of this invention, unless otherwise stated, "a plurality of" means two or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0223] In the textual description of this invention, it is understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing and simplifying the embodiments of this invention, and do not indicate or imply that the structures, devices, or elements referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, these descriptions should not be construed as limiting the invention.

[0224] In the textual description of this invention, it is understood that, unless explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0225] In the claims, description, and accompanying drawings of this invention, the term "plural" refers to two or more. Unless otherwise explicitly defined, the terms "upper," "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the invention and simplifying the description process, not to indicate or imply that the device or element referred to must have the described specific orientation, or be constructed and operated in a specific orientation. Therefore, these descriptions should not be construed as limiting the invention. The terms "connect," "install," "fix," etc., should be interpreted broadly. For example, "connect" can be a fixed connection between multiple objects, a detachable connection between multiple objects, or an integral connection; it can be a direct connection between multiple objects or an indirect connection between multiple objects through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in this invention can be understood based on the specific circumstances described above.

[0226] In the claims, description, and accompanying drawings of this invention, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In the claims, description, and accompanying drawings of this invention, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0227] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for diagnosing a compressor, characterized in that, The compressor is associated with a compressor controller, and the diagnostic method includes: Obtain the input variables of the compressor controller; The input variable is processed to obtain a target parameter value, which includes at least one of the following: a first target parameter value obtained by processing the input variable in the steady-state time domain, a second target parameter value obtained by processing the input variable in the transient time domain, and a third target parameter value obtained by processing the input variable in the steady-state frequency domain. The diagnostic result of the compressor is determined based on the comparison between the target parameter value and the corresponding parameter threshold. When the target parameter value includes a first target parameter value, determining the compressor's diagnostic result based on the comparison between the target parameter value and the corresponding parameter threshold specifically includes: The compressor malfunctions when the first target parameter value is greater than the first parameter threshold or when the first target parameter value is less than the second parameter threshold. Wherein, the first parameter threshold is greater than the second parameter threshold, and the first target parameter value includes the magnitude of the magnetic flux or the magnitude of the back electromotive force; When the target parameter value includes a second target parameter value, determining the diagnostic result of the compressor based on the comparison result between the target parameter value and the corresponding parameter threshold specifically includes: If, within a first time period, the cumulative number of times the second target parameter value exceeds the corresponding parameter threshold exceeds a preset number, the compressor malfunctions. The second target parameter value includes the current difference or the speed difference; When the target parameter value includes a third target parameter value, determining the compressor's diagnostic result based on the comparison between the target parameter value and the corresponding parameter threshold specifically includes: The compressor malfunctions when the phase difference is greater than the third parameter threshold or less than the fourth parameter threshold. Wherein, the third parameter threshold is greater than the fourth parameter threshold, and the phase difference is obtained by processing the given speed value and the actual speed value of the compressor as follows, and the third target parameter value is the phase difference: The fluctuation component of the rotational speed is determined based on the given rotational speed value and the actual rotational speed value; Determine the phase difference between the current on the q-axis of the compressor and the fluctuation component in a two-phase rotating coordinate system.

2. The compressor diagnostic method according to claim 1, characterized in that, When the first target parameter value includes the flux linkage amplitude, the input variable includes the flux linkage when the compressor speed is in a stable phase in a two-phase stationary coordinate system.

3. The compressor diagnostic method according to claim 1, characterized in that, When the first target parameter value includes the amplitude of the back electromotive force, the input variable includes the back electromotive force when the compressor speed is in a stable phase in a two-phase rotating coordinate system.

4. The method for diagnosing a compressor according to claim 2 or 3, characterized in that, Also includes: In the event of a compressor malfunction, the cause of the malfunction is output, including the decay of the magnetic properties of the permanent magnet.

5. The compressor diagnostic method according to claim 1, characterized in that, When the second target parameter value includes the current difference, the current difference is the output value of the dq current controller when the given current value and the actual current value of the compressor are input to the dq current controller.

6. The method for diagnosing a compressor according to claim 1, characterized in that, When the second target parameter value includes the speed difference value, the speed difference value is the output value of the speed controller when the given speed value and the actual speed value of the compressor are input to the speed controller.

7. The method for diagnosing a compressor according to claim 5 or 6, characterized in that, Also includes: In the event of a compressor malfunction, the cause of the malfunction is output, including the presence of decay in the compressor's mechanical components.

8. The method for diagnosing a compressor according to claim 1, characterized in that, When the target parameter value includes a third target parameter value, determining the compressor's diagnostic result based on the comparison between the target parameter value and the corresponding parameter threshold specifically includes: The compressor malfunctions when the normalized fluctuation component is greater than the corresponding parameter threshold. The normalized fluctuation component is obtained by processing the given speed value and the actual speed value of the compressor as follows: The fluctuation component of the rotational speed is determined based on the given rotational speed value and the actual rotational speed value; Determine the component of the rotational speed fluctuation at the mechanical rotational speed; The normalized fluctuation component is obtained by normalizing the ratio of the component of the rotational speed fluctuation at the mechanical speed to the current amplitude of the compressor.

9. The method for diagnosing a compressor according to claim 1 or 8, characterized in that, Also includes: In the event of a compressor malfunction, the cause of the malfunction is output, including non-uniform damage to the compressor's mechanical components.

10. A diagnostic device for a compressor, characterized in that, A diagnostic method for implementing the compressor according to any one of claims 1 to 9, wherein the compressor is associated with a compressor controller, and the diagnostic device comprises: An acquisition unit is used to acquire the input variables of the compressor controller; The processing unit is configured to process the input variable to obtain a target parameter value, wherein the target parameter value includes at least one of the following: a first target parameter value obtained by processing the input variable in the steady-state time domain, a second target parameter value obtained by processing the input variable in the transient time domain, and a third target parameter value obtained by processing the input variable in the steady-state frequency domain. The diagnostic unit is used to determine the diagnostic result of the compressor based on the comparison result between the target parameter value and the corresponding parameter threshold.

11. A diagnostic device for a compressor, characterized in that, include: A controller and a memory, wherein the memory stores a program or instructions, and the controller, when executing the program or instructions in the memory, implements the steps of the diagnostic method as described in any one of claims 1 to 9.

12. A readable storage medium, characterized in that, The readable storage medium stores a program or instructions that, when executed by a processor, implement the steps of the diagnostic method as described in any one of claims 1 to 9.

13. A compressor, characterized in that, include: Diagnostic device for compressor as described in claim 10 or 11; and / or The readable storage medium as described in claim 12.

14. A vehicle, characterized in that, include: The compressor as described in claim 13.

15. The vehicle according to claim 14, characterized in that, The vehicle also includes: An output device, connected to the compressor, outputs the cause of the malfunction based on a problem with the compressor.

Images