Fault diagnosis method, system and device for pumped storage generator motor
By collecting and analyzing the weight coefficients of various operating parameters in real time in the pumped storage power generation motor and calculating the short-circuit fault judgment value, the problem that the phase-to-phase short-circuit fault of the stator winding is easily misjudged, and the accuracy and reliability of fault diagnosis are improved.
Patent Information
- Application Number
- CN202510290950.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-12
- Publication Date
- 2025-06-13
- Estimated Expiration
- 2045-03-12
AI Technical Summary
In fault diagnosis of pumped storage power generator motors, phase-to-phase short circuit faults of stator windings are easily misjudged as other types of faults, resulting in low diagnostic accuracy.
By obtaining the three-phase current, power supply voltage, bearing vibration signal and stator winding temperature during the operation of the generator motor, the power supply voltage weight coefficient, stator winding temperature weight coefficient and stator current weight coefficient are calculated, and combined with these weight coefficients and real-time data, the short-circuit fault judgment value is calculated to accurately diagnose the phase-to-phase short-circuit fault of the stator winding.
It improves the accuracy of fault diagnosis of pumped storage power generation motors, reduces the rate of misjudgment, and ensures the reliability of fault diagnosis.
Smart Images
Figure CN120142930A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of engine fault diagnosis, and particularly to a fault diagnosis method, system and device for a pumped-storage power generation motor. Background Art
[0002] When there is surplus power in the power system, the pumped-storage power generation motor can operate as a motor to convert electrical energy into the potential energy of water for storage; when the power system has a peak load, the pumped-storage power generation motor can operate as a generator to release water for power generation, converting the potential energy of water into electrical energy, thereby regulating the load and ensuring the stability of power supply.
[0003] As the core component of the pumped-storage unit, the generator motor has a high rotational speed, a large single-pole capacity, and frequent switching between the pumping condition and the power generation condition. Compared with conventional hydro-turbine units, it is more prone to failure. During the process of diagnosing the starting fault of the pumped-storage power generation motor, since the data change characteristics of the inter-phase short-circuit fault of the stator winding are similar to those of other faults, the inter-phase short-circuit fault of the stator winding is often misjudged as other types of faults, resulting in a low accuracy rate of fault diagnosis. Summary of the Invention
[0004] In order to solve the above technical problems, the purpose of the present application is to provide a fault diagnosis method, system and device for a pumped-storage power generation motor, and the specific technical solutions adopted are as follows:
[0005] In a first aspect, an embodiment of the present application provides a fault diagnosis method for a pumped-storage power generation motor, including the following steps:
[0006] Obtain the three-phase current, power supply voltage and current, bearing vibration signal, and stator winding temperature during the operation of the pumped-storage power generation motor;
[0007] Analyze the difference between the power supply current at the previous adjacent moment and the rated current of the motor power supply at each moment, and combine the fluctuation degree of the power supply current data at multiple moments before each moment and the zero-value proportion in the power supply voltage and current at multiple moments before to obtain the power supply voltage weight coefficient at each moment;
[0008] Obtain the stator winding temperature weight coefficient at each moment according to the amplitude of the bearing vibration signal at the previous adjacent moment and the change degree of the vibration signal amplitudes at multiple moments before each moment;
[0009] Obtain the stator current weight coefficient at each moment through the three-phase current of the stator winding at the previous adjacent moment and the difference between the maximum value and the minimum value in the three-phase current;
[0010] According to three weighting coefficients and in combination with the power supply voltage, stator winding temperature, and three-phase current at each moment, a short-circuit fault discrimination value at each moment is obtained;
[0011] Based on the short-circuit fault discrimination value, a short-circuit fault of the pumped-storage motor generator is diagnosed.
[0012] Preferably, the calculation method for the power supply voltage weighting coefficient at each moment is as follows:
[0013] In the formula, S i represents the power supply voltage weighting coefficient at the i-th moment; I i-1 represents the power supply current data collected at the (i - 1)-th moment; EI represents the rated current of the power supply; exp() represents the natural exponential function; A i represents the power supply current sequence at the i-th moment; D() represents the variance; g m,I represents the proportion of zero values in the power supply current data within m moments before the i-th moment; g m,U represents the proportion of zero values in the power supply voltage data within m moments before the i-th moment.
[0014] Preferably, the power supply currents at multiple moments before the i-th moment are arranged in chronological order to form the power supply current sequence at the i-th moment.
[0015] Preferably, the calculation method for the stator winding temperature weighting coefficient at each moment is as follows:
[0016] In the formula, G i is the stator winding temperature weighting coefficient at the i-th moment; Y i-1 represents the amplitude of the bearing vibration signal at the (i - 1)-th moment; P i represents the bearing vibration amplitude sequence at the i-th moment.
[0017] Preferably, the amplitudes of the bearing vibration signals at multiple moments before the i-th moment are arranged in chronological order as the bearing vibration amplitude sequence at the i-th moment.
[0018] Preferably, the calculation method for the stator current weighting coefficient at each moment is as follows:
[0019] V i = s i-1,max (s i-1,max - s i-1,min ); In the formula, V i is the stator current weighting coefficient at the i-th moment; s i-1,max represents the maximum value among the three-phase currents of the stator winding at the (i - 1)-th moment; s i-1,min represents the minimum value among the three-phase currents of the stator winding at the (i - 1)-th moment.
[0020] Preferably, the calculation method of the short - circuit fault discrimination value at each moment is as follows:
[0021]
[0022] wherein, B i is the short - circuit fault discrimination value at the i - th moment; ω i,1 , ω i,2 and ω i,3 are respectively the normalized power supply voltage weight coefficient, stator winding temperature weight coefficient and stator current weight coefficient at the i - th moment; t i-1 represents the stator winding temperature at the (i - 1) - th moment; t i,m represents the average value of the stator winding temperatures at m moments before the i - th moment; relu() is the rectified linear unit function; E i-1 represents the power supply voltage at the (i - 1) - th moment; E represents the rated voltage of the power supply; h() is the rectification function; σ is a constant to prevent the denominator from being zero.
[0023] Preferably, diagnosing the short - circuit fault of the pumped - storage motor according to the short - circuit fault discrimination value specifically includes: when the short - circuit fault discrimination value is greater than the preset threshold, there is an inter - phase short - circuit of the stator winding at the corresponding moment.
[0024] In a second aspect, an embodiment of the present application further provides a fault diagnosis system for a pumped - storage motor, including a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, the steps of the above - mentioned fault diagnosis method for a pumped - storage motor are implemented.
[0025] In a third aspect, an embodiment of the present application further provides a fault diagnosis device for a pumped - storage motor. A computer program is stored in the device, and when the computer program is executed by the processor, the above - mentioned fault diagnosis method for a pumped - storage motor is implemented.
[0026] As can be seen from the above, the fault diagnosis method, system and device for a pumped - storage motor provided by the present application have at least the following beneficial effects:
[0027] According to the characteristics of the power supply voltage, stator winding temperature and three - phase current imbalance under different fault types, the present application constructs the power supply voltage weight coefficient, stator winding temperature weight coefficient and stator current weight coefficient, which can judge the similarity degree between the data characteristics of these three types of data and the data characteristics that should be generated by the inter - phase short - circuit of the stator winding. Then, when judging whether the fault type is the inter - phase short - circuit of the stator winding, weights are assigned to the three types of data respectively, so as to eliminate the interference of power supply abnormalities, bearing losses or overload operations during the fault diagnosis process, making the diagnosis result more accurate. Brief Description of the Drawings
[0028] To more clearly illustrate the technical solutions and advantages in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.
[0029] Figure 1 It is a flowchart of the steps of a fault diagnosis method for a pumped-storage power generation motor provided by the present application. Detailed Embodiments
[0030] To further elaborate on the technical means and effects adopted by the present application to achieve the intended invention purpose, the following, in combination with the drawings and preferred embodiments, details the specific embodiments, structures, features and effects of a fault diagnosis method, system and device for a pumped-storage power generation motor proposed according to the present application. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.
[0031] Unless otherwise specified and limited, terms such as "including", "comprising" or any other variant thereof are intended to cover non-exclusive inclusion, so that a circuit structure, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of another identical element in the article or device including the said element. In addition, the term "and / or" used herein includes any and all combinations of one or more of the related listed items. All technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present application belongs.
[0032] The following specifically describes the specific solutions of a fault diagnosis method, system and device for a pumped-storage power generation motor provided by the present application in combination with the drawings.
[0033] Please refer to Figure 1 , which shows a flowchart of the steps of a fault diagnosis method for a pumped-storage power generation motor provided by an embodiment of the present application, including the following steps:
[0034] Step 1: Obtain the three-phase current, power supply voltage and current, bearing vibration signal, and stator winding temperature during the operation of the pumped-storage power generation motor.
[0035] The pumped-storage unit plays a role in filling valleys and regulating peaks in the power system. Generally, it needs to start and stop at least twice a day. In actual application, some pumped-storage power stations require more frequent start and stop. Frequent start and stop will cause various faults in the generator-motor. When the fault is relatively minor, the generator-motor can still continue to operate. As the degree of the fault deepens, the generator-motor will show the phenomenon of inability to start. Since the fault usually exists before the starting fault occurs, the cause of the starting fault can be judged by real-time monitoring of the data of the generator-motor during operation.
[0036] Install voltage sensors, current sensors, vibration sensors and temperature sensors in the internal system of the pumped-storage generator-motor to collect the three-phase current (phase a, phase b, phase c), power supply voltage, power supply current, bearing vibration signal and stator winding temperature of the pumped-storage generator-motor in real time during operation. In this embodiment, the data acquisition frequency is 5Hz.
[0037] Furthermore, in this embodiment, the collected various data are respectively used as the input of the median filtering algorithm to denoise the data. Among them, the median filtering algorithm is a well-known technology, and the specific process will not be elaborated.
[0038] Step 2: Analyze the difference between the power supply current at the previous adjacent moment and the rated current of the motor power supply at each moment, and combine the fluctuation degree of the power supply current data at multiple moments before each moment and the zero value ratio of the power supply voltage and current at multiple moments before to obtain the power supply voltage weight coefficient at each moment.
[0039] The reasons for the starting fault of the pumped-storage generator-motor generally include power supply abnormality, mechanical damage (bearing damage, component damage) and circuit fault. Among them, the circuit fault includes interphase short circuit of the stator winding, turn-to-turn short circuit of the stator winding, short circuit of the excitation circuit, etc. Since the environment of the pumped-storage power station is relatively humid, when water enters the stator winding, it is easy to cause insulation damage or direct short circuit of the stator winding, making the interphase short circuit fault of the stator winding one of the common faults in the circuit fault. When there is an interphase short circuit in the stator winding, the unbalance of the three-phase circuit will cause the generator-motor to not obtain enough starting torque and thus cannot start. Therefore, when the pumped-storage generator-motor has a starting fault, it is necessary to diagnose whether the starting failure is caused by the interphase short circuit of the stator winding.
[0040] When the generator-motor has an interphase short circuit fault in the stator winding, the current in the short-circuited phase of the stator winding will be much larger than the other two phases, resulting in unbalance of the three-phase current; in the case of an interphase short circuit in the stator winding, the power supply needs to provide more current to meet the needs of the motor, which may cause the power supply voltage to drop; in addition, a large amount of heat will be generated by the short-circuit current during the interphase short circuit of the stator winding, resulting in an increase in the temperature of the stator winding.
[0041] Although the above characteristics will appear when there is an interphase short circuit in the stator winding, the appearance of the above characteristics does not necessarily mean an interphase short circuit in the stator winding. For example, when the power supply voltage drops, it may be due to a power supply fault; when the temperature of the stator winding rises, it may be caused by bearing damage resulting in vibration of the generator motor, causing mechanical friction between the stator winding and adjacent components, leading to an increase in the temperature of the stator winding; when the three-phase current of the stator winding is unbalanced, it may be due to the generator motor operating overloaded.
[0042] When the reason for the power supply voltage drop is a power supply fault, when the power supply voltage drops, the power supply current will also drop or show abnormal fluctuations, and when the power supply is completely interrupted, the power supply voltage and power supply current may become zero; while when the reason for the power supply voltage drop is an interphase short circuit in the stator winding, the current in the shorted phase increases, causing the power supply current to increase.
[0043] Therefore, based on the above characteristics, analyze the difference between the power supply current at the previous adjacent moment and the rated current of the motor power supply at each moment, and combine the fluctuation degree of the power supply current data and the proportion of zero values in the power supply voltage and current to construct a power supply voltage weight coefficient. In this embodiment, the calculation formula for the power supply voltage weight coefficient at each moment is:
[0044] In the formula, S i represents the power supply voltage weight coefficient at the i-th moment; I i-1 represents the power supply current data collected at the (i - 1)-th moment; EI represents the rated current of the power supply; exp() represents the natural exponential function; A i represents the power supply current sequence at the i-th moment. In this embodiment, the power supply currents at m moments before the i-th moment are arranged in chronological order to form the power supply current sequence at the i-th moment, where m takes the value of 20 in this embodiment; D() represents the variance; g m,I represents the proportion of zero values in the power supply current data within m moments before the i-th moment; g m,U represents the proportion of zero values in the power supply voltage data within m moments before the i-th moment.
[0045] When the value of exp(I i-1 - EI) is larger, it indicates that the power supply current at the (i - 1)-th moment is larger than the rated current, and further indicates that the power supply voltage drop is more likely to be caused by an interphase short circuit in the stator winding; when D(A i ) is smaller, it indicates that the power supply currents in the recent period are more similar, and further indicates that the possibility of abnormal fluctuations in the power supply current in the recent period is smaller, then the reason for the power supply voltage drop is more likely to be an interphase short circuit in the stator winding; if g m,I , g m,UThe smaller it is, the smaller the proportion of zero values in the power supply current data and power supply voltage data in the recent period, and thus the smaller the possibility that the reason for the power supply voltage drop is a power supply fault.
[0046] Step 3: According to the amplitude of the bearing vibration signal at the previous adjacent moment of each moment and the degree of change in the vibration signal amplitudes at multiple moments before each moment, obtain the stator winding temperature weight coefficient at each moment.
[0047] Furthermore, when the reason for the increase in the stator winding temperature is bearing damage, the intensity of the vibration signal at the bearing will increase, and the vibration signal in the recent period will be significantly different from the vibration signal in the previous period; when the reason for the increase in the stator winding temperature is an inter-phase short circuit of the stator winding, the vibration signal at the bearing usually does not change.
[0048] Therefore, by analyzing the degree of change in the amplitude of the bearing vibration signal, the stator winding temperature weight coefficient at each moment is obtained, which is used to characterize the possibility that the reason for the increase in the stator winding temperature is an inter-phase short circuit of the stator winding. In this embodiment, the calculation formula for the stator winding temperature weight coefficient at each moment is:
[0049] In the formula, G i is the stator winding temperature weight coefficient at the i-th moment; Y i-1 represents the amplitude of the bearing vibration signal at the (i - 1)-th moment; P i represents the bearing vibration amplitude sequence at the i-th moment. In this embodiment, the amplitudes of the bearing vibration signals at 20 moments before the i-th moment are arranged in chronological order as the bearing vibration amplitude sequence at the i-th moment.
[0050] It can be understood that the smaller the value of Y i-1 , the weaker the intensity of the bearing vibration signal at the (i - 1)-th moment, and thus the more likely the reason for the increase in the stator winding temperature is an inter-phase short circuit of the stator winding; the smaller D(P i ), the more similar the bearing vibration signals in the recent period, and thus the more likely the reason for the increase in the stator winding temperature is caused by an inter-phase short circuit of the stator winding.
[0051] Step 4: Through the three-phase current of the stator winding at the previous adjacent moment of each moment and the difference between the maximum value and the minimum value in the three-phase current, obtain the stator current weight coefficient at each moment.
[0052] Further, when the cause of the unbalance of the three-phase current in the stator winding is overload operation, the currents of each phase of the stator winding will not exceed the rated current by too much, and the unbalance degree of the three-phase current is relatively small. When the cause of the unbalance of the three-phase current in the stator winding is the interphase short circuit of the stator winding, a large circulating current will flow through the short-circuited coil, and the three-phase current will be seriously unbalanced.
[0053] Based on the above characteristics, analyze the difference between the maximum and minimum values of the three-phase current in the stator winding at each moment, and then obtain the stator current weight coefficient at each moment. In this embodiment, the specific calculation formula is:
[0054] V i =s i-1,max (s i-1,max -s i-1,min );wherein, V i is the stator current weight coefficient at the i-th moment; s i-1,max represents the maximum value of the three-phase current in the stator winding at the (i - 1)-th moment; s i-1,min represents the minimum value of the three-phase current in the stator winding at the (i - 1)-th moment.
[0055] It can be understood that the larger the value of s i-1,max , that is, the larger the maximum value of the three-phase current at the (i - 1)-th moment, the greater the possibility that the cause of the unbalance of the three-phase circuit of the stator winding is the interphase short circuit of the stator winding; the larger the value of (s i-1,max -s i-1,min ), that is, the higher the unbalance degree of the three-phase circuit current of the stator winding and the greater the current difference at the (i - 1)-th moment, the greater the possibility that the cause of the unbalance of the three-phase circuit of the stator winding is the interphase short circuit of the stator winding.
[0056] Step Five: Obtain the short-circuit fault discrimination value at each moment according to the three weight coefficients and in combination with the power supply voltage, stator winding temperature, and three-phase current at each moment.
[0057] Further, construct the short-circuit fault discrimination value according to the power supply voltage weight coefficient, stator winding temperature weight coefficient, and stator current weight coefficient at each moment. In this embodiment, the specific calculation formula for the short-circuit fault discrimination value at each moment is:
[0058]
[0059] wherein, B i is the short-circuit fault discrimination value at the i-th moment; ω i,1 , ω i,2 and ω i,3 are respectively the normalized power supply voltage weight coefficient, stator winding temperature weight coefficient, and stator current weight coefficient at the i-th moment, wherein, ωi,1 = tanh(S i ), ω i,2 = tanh(G i ), ω i,3 = tanh(V i ); tanh() is the hyperbolic tangent function, used to normalize the input data; t i-1 represents the stator winding temperature at the (i - 1)-th moment; t i,n represents the average value of the stator winding temperatures at m moments before the i-th moment; relu() is the rectified linear unit function; E i-1 represents the power supply voltage at the (i - 1)-th moment; E represents the rated voltage of the power supply; h() is the rectification function, and its expression is σ is a constant to prevent the denominator from being zero, and any positive number less than 0.1 can be taken. In this embodiment, the value is 0.01.
[0060] It can be understood that the more unbalanced the three-phase current is at the (i - 1)-th moment, the higher the stator winding temperature is, and the smaller the power supply voltage is, the more likely the cause of the starting fault at the i-th moment is the inter-phase short circuit of the stator winding.
[0061] Step Six: Diagnose the short-circuit fault of the pumped-storage motor according to the short-circuit fault discrimination value.
[0062] Furthermore, according to the short-circuit fault discrimination values at each moment, diagnose and analyze the short-circuit fault during the operation of the pumped-storage motor. Specifically, in this embodiment, when the short-circuit fault discrimination value is greater than the threshold z, there is an inter-phase short circuit of the stator winding at the corresponding moment. Among them, in this embodiment, the value of z is 3, and the implementer can determine it according to the actual situation.
[0063] Based on the same inventive concept as the above method, an embodiment of the present application also provides a pumped-storage motor fault diagnosis system, including a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, it implements the steps of any one of the above methods for diagnosing the fault of a pumped-storage motor.
[0064] At the same time, an embodiment of the present application also provides a pumped-storage motor fault diagnosis device. A computer program is stored in the device, and when the computer program is executed by the processor, it implements any one of the above methods for diagnosing the fault of a pumped-storage motor.
[0065] It can be understood that the above order of the embodiments of the present application is only for description and does not represent the superiority or inferiority of the embodiments. In addition, the specific embodiments of this specification have been described. Further, the processes depicted in the drawings do not necessarily require the particular order or sequential order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.
[0066] Each embodiment in this specification is described in a progressive manner. For the same or similar parts among the embodiments, reference can be made to each other, and the key point of each embodiment is to illustrate the differences from other embodiments.
[0067] The above content is only the implementation manner of the present application and is not used to limit the scope of the present application. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied to other related technical fields, shall be equally included in the protection scope of the present application.
Claims
1. A method for diagnosing faults of a pumped storage generator motor, characterized in that: The following steps are involved: Obtain the three-phase current, power supply voltage and current, bearing vibration signal, and stator winding temperature of the pumped storage generator motor during operation; Analyze the difference between the power supply current at the previous adjacent moment and the rated current of the motor power supply at each moment, and obtain the power supply voltage weight coefficient at each moment by combining the fluctuation degree of the power supply current data at multiple moments before each moment and the proportion of zero values in the power supply voltage and current at multiple moments before each moment; Obtaining the stator winding temperature weight coefficient at each moment according to the amplitude of the bearing vibration signal at the previous adjacent moment and the degree of change of the vibration signal amplitude at multiple moments before each moment; Obtain the stator current weight coefficient at each moment by calculating the difference between the three-phase current of the stator winding at the previous adjacent moment and the maximum and minimum values of the three-phase current; According to the three weight coefficients and combined with the power supply voltage, stator winding temperature and three-phase current at each moment, the short-circuit fault judgment value at each moment is obtained; The short-circuit fault of the pumped-storage generator motor is diagnosed according to the short-circuit fault discrimination value.
2. A method for diagnosing faults of a pumped storage generator motor as claimed in claim 1, characterized in that: The calculation method of the power supply voltage weight coefficient at each moment is: In the formula, S i Represents the power supply voltage weight coefficient at the i-th moment; I i-1 represents the power supply current data collected at the i-1th moment; EI represents the rated current of the power supply; exp() represents the natural exponential function; A i represents the power supply current sequence at the i-th moment; D() represents the variance; g m,I represents the proportion of zero values in the power supply current data in the m moments before the i-th moment; g m,U Indicates the proportion of zero values in the power supply voltage data in the m moments before the i-th moment.
3. A method for diagnosing faults of a pumped storage generator motor as claimed in claim 2, characterized in that: The power supply currents at multiple moments before the i-th moment are arranged in chronological order to form a power supply current sequence at the i-th moment.
4. A method for diagnosing faults of a pumped storage generator motor as claimed in claim 1, characterized in that: The calculation method of the stator winding temperature weight coefficient at each moment is: In the formula, G i is the stator winding temperature weight coefficient at the i-th moment; Y i-1 represents the amplitude of the bearing vibration signal at the i-1th moment; P i represents the bearing vibration amplitude sequence at the i-th moment.
5. A method for diagnosing faults of a pumped storage generator motor as claimed in claim 4, characterized in that: The amplitudes of the bearing vibration signals at multiple moments before the i-th moment are arranged in chronological order as the bearing vibration amplitude sequence at the i-th moment.
6. A method for diagnosing faults of a pumped storage generator motor as claimed in claim 1, characterized in that: The calculation method of the stator current weight coefficient at each moment is: V i =s i-1,max (s i-1,max -s i-1,min );Wherein, V i is the stator current weight coefficient at the i-th moment; s i-1,max represents the maximum value of the three-phase current of the stator winding at the i-1th moment; s i-1,min It represents the minimum value of the three-phase current of the stator winding at the i-1th moment.
7. A method for diagnosing faults of a pumped storage generator motor as claimed in claim 1, characterized in that: The calculation method of the short-circuit fault discrimination value at each moment is: Among them, B i is the short-circuit fault judgment value at the i-th moment; ω i,1 ,ω i,2 and ω i,3 are the normalized power supply voltage weight coefficient, stator winding temperature weight coefficient and stator current weight coefficient at the i-th moment respectively; t i-1 represents the stator winding temperature at the i-1th moment; t i,m represents the average value of the stator winding temperature at m moments before the i-th moment; relu() is a linear rectification function; E i-1 represents the power supply voltage at the i-1th moment; E represents the rated voltage of the power supply; h( ) is the rectification function; σ is a constant to prevent the denominator from being zero.
8. A method for diagnosing faults of a pumped storage generator motor as claimed in claim 1, characterized in that: The diagnosing the short-circuit fault of the pumped-storage generator motor according to the short-circuit fault judgment value specifically includes: when the short-circuit fault judgment value is greater than a preset threshold value, a stator winding phase-to-phase short circuit occurs at a corresponding moment.
9. A pumped storage generator motor fault diagnosis system, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the steps of a pumped-storage generator motor fault diagnosis method as described in any one of claims 1-8 are implemented.
10. A pumped storage generator motor fault diagnosis device, wherein a computer program is stored in the device, characterized in that: When the computer program is executed by a processor, a pumped-storage generator motor fault diagnosis method as described in any one of claims 1 to 8 is implemented.