Pulse power supply and method for automatic detection of partial discharge of variable frequency motor

Abstract

The application provides a pulse power supply and method for automatic detection of partial discharge of a variable-frequency motor, and relates to the field of motor detection. The pulse power supply comprises a high-voltage pulse power supply module, which is used for converting a high-voltage direct-current power supply into a first pulse power supply and a second pulse power supply. The voltage amplitude of the first pulse power supply is the same as that of the second pulse power supply, and the polarity of the first pulse power supply is opposite to that of the second pulse power supply. A partial discharge detection module is used for collecting a space electromagnetic signal during the process of discharging detection of a variable-frequency motor to be detected by the first pulse power supply and the second pulse power supply. A control module is used for acquiring pulse waveform parameters and controlling the high-voltage pulse power supply module to generate the first pulse power supply and the second pulse power supply corresponding to the pulse parameters. The control module is also used for generating a discharging detection result corresponding to the variable-frequency motor to be detected based on the space electromagnetic signal. The application has the advantage of improving the accuracy of partial discharge detection of the variable-frequency motor.

Description

Technical Field

[0001] This invention relates to the field of motor testing, and in particular to a pulse power supply and method for automatic detection of partial discharge in variable frequency motors. Background Technology

[0002] Compared with traditional AC motors, variable frequency motors have advantages such as energy saving, easy speed adjustment, and easy starting. Therefore, electric vehicles generally use variable frequency motors as drive motors. However, at the same time, variable frequency motors operate under high frequency and rapidly changing pulse voltage, and the insulation will be subjected to a more severe electrical and thermal stress environment, which will accelerate the aging of the motor insulation and cause the insulation to fail prematurely during operation.

[0003] The use of third-generation wide-bandgap power devices can significantly improve the efficiency and energy density of variable frequency motors. However, it also brings new problems to the already challenging insulation system of variable frequency motors. These problems are mainly manifested in the following ways: the switching frequency of traditional IGBTs will increase from a maximum of 20kHz to 200kHz, inevitably reducing the rise time of repetitive pulses to below 100ns; at the rising and falling edges of high-frequency pulse voltages, impedance mismatch between the cable and the motor ends can lead to severe overvoltages at the motor ends. Furthermore, the high-frequency changing pulse voltages are more likely to intensify the local electric field in the insulation system, triggering partial discharge and accelerating the electrical aging of the motor insulation.

[0004] Currently, partial discharge detection of variable frequency motors is mostly done manually. However, the pulse power supply is bulky and the parameters are not flexible, resulting in inaccurate test results and low testing efficiency. Furthermore, for the testing of phase-to-phase insulation of variable frequency motors in electric vehicles, most tests use unipolar testing, where one phase is connected to the test voltage while the casing and the other two phases are grounded. This connection method causes the main insulation to bear extremely high voltage, so the main insulation discharges before the phase-to-phase insulation discharges, making it impossible to accurately test the partial discharge initiation voltage of the phase-to-phase insulation. This seriously hinders the development of insulation for variable frequency motors in electric vehicles.

[0005] Therefore, there is a need to provide a pulse power supply and method for automatic detection of partial discharge in variable frequency motors, in order to improve the accuracy of partial discharge detection in variable frequency motors. Summary of the Invention

[0006] One embodiment of this specification provides a pulse power supply for automatic partial discharge detection of a variable frequency motor, comprising: a high-voltage pulse power supply module for converting a high-voltage DC power supply into a first pulse power supply and a second pulse power supply, wherein the voltage amplitude of the first pulse power supply is the same as that of the second pulse power supply, and the polarity of the first pulse power supply and the second pulse power supply are opposite; wherein the first pulse power supply and the second pulse power supply are electrically connected to the variable frequency motor under test, and the first pulse power supply and the second pulse power supply are used to perform discharge detection on the variable frequency motor under test; a partial discharge detection module for acquiring spatial electromagnetic signals during the discharge detection of the variable frequency motor under test by the first pulse power supply and the second pulse power supply; and a control module for acquiring pulse waveform parameters, and controlling the high-voltage pulse power supply module to generate the first pulse power supply and the second pulse power supply corresponding to the pulse parameters based on the pulse waveform parameters, and further for generating the discharge detection result corresponding to the variable frequency motor under test based on the spatial electromagnetic signals.

[0007] In some embodiments, the high-voltage pulse power supply module includes a high-voltage input terminal, a first-order RC circuit, a first solid-state high-voltage DC switch, and a second solid-state high-voltage DC switch connected in sequence. The first solid-state high-voltage DC switch is used to chop the high-voltage DC power supply based on a first trigger signal generated by the control module according to the pulse waveform parameters to generate the first pulse power supply. The second solid-state high-voltage DC switch is used to chop the high-voltage DC power supply based on a second trigger signal generated by the control module according to the pulse waveform parameters to generate the second pulse power supply.

[0008] In some embodiments, the partial discharge detection module includes an ultra-high frequency antenna, an oscilloscope, and a high-pass filter, wherein the ultra-high frequency antenna is connected to the oscilloscope through the high-frequency filter, and the control module communicates with the oscilloscope.

[0009] In some embodiments, the pulse waveform parameters include at least the pulse power amplitude, frequency, and duty cycle.

[0010] In some embodiments, the casing of the variable frequency motor under test is grounded, the first phase of the variable frequency motor under test is electrically connected to the first pulse power supply, and both the first phase and the second phase of the variable frequency motor under test are electrically connected to the second pulse power supply.

[0011] In some embodiments, a high-voltage relay is connected in series between the high-voltage input terminal and the first-order RC circuit; the control module is also used to control the high-voltage relay to disconnect the connection between the high-voltage input terminal and the first-order RC circuit when a short circuit occurs in the high-voltage DC power supply.

[0012] In some embodiments, the high-voltage input terminal includes a high-voltage DC power supply connection port and a high-voltage energy storage capacitor.

[0013] One embodiment of this specification provides a method for automatic partial discharge detection of a variable frequency motor. Based on the aforementioned pulse power supply, a discharge test is performed on the variable frequency motor under test. The method includes the following steps: acquiring pulse waveform parameters; grounding the casing of the variable frequency motor under test; electrically connecting the first phase of the variable frequency motor under test to the first pulse power supply; electrically connecting the first phase and the second phase of the variable frequency motor under test to the second pulse power supply; generating a first pulse power supply and a second pulse power supply corresponding to the pulse parameters based on the pulse waveform parameters; performing discharge detection on the variable frequency motor under test; acquiring spatial electromagnetic signals during the discharge detection process of the variable frequency motor under test by the first pulse power supply and the second pulse power supply; and generating a discharge detection result corresponding to the variable frequency motor under test based on the spatial electromagnetic signals.

[0014] In some embodiments, generating the discharge detection result corresponding to the variable frequency motor under test based on the spatial electromagnetic signal includes: determining whether a discharge has occurred by using the standard deviation corresponding to the spatial electromagnetic signal; when it is determined that a discharge has occurred, ending the discharge test and generating the discharge detection result corresponding to the variable frequency motor under test.

[0015] In some embodiments, the standard deviation of the spatial electromagnetic signal is calculated based on the following formula:

[0016]

[0017] Wherein, σ(t) j Let ) be the standard deviation of N spatial electromagnetic signals at point j, where N is the total number of spatial electromagnetic signals; x(t) i (j) represents the value of the i-th spatial electromagnetic signal at point j; Let J be the average of N spatial electromagnetic signals at point j.

[0018] Compared with existing technologies, the pulse power supply and method for automatic detection of partial discharge in variable frequency motors provided in this specification have at least the following advantages:

[0019] 1. The output waveform is stable and adjustable, with a rise time in the nanosecond range. The pulse power supply for automatic detection of partial discharge in variable frequency motors is based on a dual push-pull high-voltage solid-state switch full-bridge structure, which is stable and reliable, with a smooth output waveform and a rise time in the nanosecond range.

[0020] 2. Small size and high integration: The pulse power supply for automatic detection of partial discharge in variable frequency motors integrates a high-voltage pulse power supply module, a partial discharge detection module, etc. into one device. It has a high degree of integration, small size, and portability.

[0021] 3. The pulse power supply used for automatic detection of partial discharge in variable frequency motors adopts a human-machine interface, which can arbitrarily configure the output waveform, including parameters such as the amplitude, frequency and duty cycle of the output pulse. It is easy to operate and can display the operating status of the pulse power supply in real time.

[0022] 4. Fast detection speed and accurate results. It adopts a high-sensitivity ultra-high frequency antenna and uses fiber optic transmission to detect partial discharge in a timely manner. The control module automatically identifies partial discharge and can accurately determine partial discharge.

[0023] 5. Good safety performance: The pulse power supply used for automatic detection of partial discharge in variable frequency motors has short circuit protection and online status detection. It can detect the operating status in real time and automatically cut off the high voltage DC power supply if an abnormality occurs.

[0024] 6. High versatility: The pulse power supply used for automatic detection of partial discharge in variable frequency motors can be used not only for automatic detection of partial discharge in the insulation of variable frequency motors in new energy vehicles, but also for pulse ablation in the biological field, demonstrating high versatility.

[0025] 7. The method for automatic detection of partial discharge in variable frequency motors effectively avoids main insulation discharge during phase-to-phase insulation (PDIV) testing. Attached Figure Description

[0026] This specification will be further described by way of exemplary embodiments, which will be described in detail with reference to the accompanying drawings. These embodiments are not limiting; in these embodiments, the same reference numerals denote the same structures, wherein:

[0027] Figure 1 This is a schematic diagram of a pulse power supply module for automatic detection of partial discharge in a variable frequency motor, as shown in some embodiments of this specification.

[0028] Figure 2 This is a structural schematic diagram of a high-voltage pulse power supply module according to some embodiments of this specification;

[0029] Figure 3 This is a wiring diagram of a high-voltage pulse power supply module and a motor under test, as shown in some embodiments of this specification.

[0030] Figure 4 This is a schematic diagram of the control module according to some embodiments of this specification;

[0031] Figure 5 This is a flowchart illustrating a method for automatic detection of partial discharge in a variable frequency motor, according to some embodiments of this specification.

[0032] Figure 6This is a schematic diagram of the discharge test process for the variable frequency motor under test, as shown in some embodiments of this specification. Detailed Implementation

[0033] To more clearly illustrate the technical solutions of the embodiments in this specification, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this specification. For those skilled in the art, these drawings can be applied to other similar scenarios without creative effort. Unless obvious from the context or otherwise specified, the same reference numerals in the drawings represent the same structures or operations.

[0034] It should be understood that the terms “system,” “device,” “unit,” and / or “module” used herein are one way to distinguish different components, elements, parts, sections, or assemblies at different levels. However, if other terms can achieve the same purpose, they may be replaced by other expressions.

[0035] As indicated in this specification and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" do not specifically refer to the singular and may also include the plural. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of expressly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0036] Flowcharts are used in this specification to illustrate the operations performed by the system according to embodiments of this specification. It should be understood that the preceding or following operations are not necessarily performed in exact order. Instead, the steps can be processed in reverse order or simultaneously. Furthermore, other operations can be added to these processes, or one or more steps can be removed from them.

[0037] Figure 1 This is a schematic diagram of a pulse power supply module for automatic partial discharge detection of a variable frequency motor, as shown in some embodiments of this specification. Figure 1 As shown, the pulse power supply for automatic partial discharge detection of variable frequency motors may include a high-voltage pulse power supply module, a partial discharge detection module, and a control module.

[0038] The high-voltage pulse power supply module can be used to convert high-voltage DC power into a first pulse power supply and a second pulse power supply. The voltage amplitude of the first pulse power supply is the same as that of the second pulse power supply, and the polarity of the first pulse power supply is opposite to that of the second pulse power supply. The parameters of both the first and second pulse power supplies are adjustable. The first and second pulse power supplies are electrically connected to the variable frequency motor under test and are used to perform discharge detection on the variable frequency motor under test.

[0039] Figure 2 This is a structural schematic diagram of a high-voltage pulse power supply module according to some embodiments of this specification, such as... Figure 2 As shown, in some embodiments, the high-voltage pulse power supply module may include a high-voltage input terminal connected in sequence. Figure 2 The circuit consists of a first-order RC circuit (not shown), a first solid-state high-voltage DC switch, and a second solid-state high-voltage DC switch. The high-voltage input terminal includes a high-voltage DC power supply connection port and a high-voltage energy storage capacitor. The first solid-state high-voltage DC switch is used to chop the high-voltage DC power supply based on a first trigger signal generated by the control module according to pulse waveform parameters, generating a first pulse power supply. The second solid-state high-voltage DC switch is used to chop the high-voltage DC power supply based on a second trigger signal generated by the control module according to pulse waveform parameters, generating a second pulse power supply. A high-voltage relay J1 is connected in series between the high-voltage input terminal and the first-order RC circuit.

[0040] Let the time constant of the circuit be τ, the output frequency of the pulse power supply be b, and the instantaneous current of the circuit when the switch is closed be A. t0+ for:

[0041]

[0042] Among them, V +DC R is the high voltage DC power supply voltage, and R is the current-limiting resistor.

[0043] After charging is complete, the transient current a(t) during the charging process can be obtained from the total response formula of a first-order RC circuit:

[0044]

[0045] Among them, A ∞ τ is the steady-state current value, and τ is the time constant.

[0046] Instantaneous power p of high voltage DC power supply +HVDC (t):

[0047]

[0048] Where u(t) is the transient voltage during the charging process.

[0049] Energy consumed by RC during charging (J) RC :

[0050]

[0051]

[0052] Among them, C X This represents the magnitude of the sample capacitance.

[0053] High voltage DC power supply output power P +HVDC :

[0054]

[0055] Where b is the frequency of the output pulse waveform.

[0056] Since the high-voltage pulse power supply module has a full-bridge structure, the power of the high-voltage pulse power supply module can be obtained as P:

[0057]

[0058] Figure 3 This is a wiring diagram of the high-voltage pulse power supply module and the motor under test, as shown in some embodiments of this specification. Figure 3 As shown, in some embodiments, the casing of the variable frequency motor under test is grounded, the first phase of the variable frequency motor under test is electrically connected to the first pulse power supply, and both the first phase and the second phase of the variable frequency motor under test are electrically connected to the second pulse power supply.

[0059] The partial discharge detection module can be used to collect spatial electromagnetic signals during the discharge detection process of the variable frequency motor under test by the first pulse power supply and the second pulse power supply.

[0060] In some embodiments, the partial discharge detection module may include at least a high-voltage differential probe, an ultra-high frequency antenna, an oscilloscope, and a high-pass filter. The output of the high-voltage differential probe is electrically connected to the input of the oscilloscope, the ultra-high frequency antenna is connected to the oscilloscope via a high-frequency filter, and the control module communicates with the oscilloscope. The high-voltage differential probe should have a bandwidth of 50MHz or higher.

[0061] The control module can be used to acquire pulse waveform parameters and, based on these parameters, control the high-voltage pulse power supply module to generate the first and second pulse power supplies corresponding to the pulse parameters.

[0062] Specifically, the control module can provide a human-machine interface, through which testers can input pulse waveform parameters, and also realize automatic step-up and step-down of the high-voltage DC power supply, automatic detection of partial discharge, and status detection of the high-voltage pulse power supply module.

[0063] In some embodiments, the pulse waveform parameters include at least the pulse power supply amplitude, frequency, and duty cycle.

[0064] In some embodiments, the control module is also configured to control the high-voltage relay to disconnect the connection between the high-voltage input terminal and the first-order RC circuit when a short circuit occurs in the high-voltage DC power supply. It is understood that after a short circuit in the power output, the high-voltage relay should be activated immediately to disconnect the power output and prevent damage to the power supply due to the short circuit.

[0065] The control module can also be used to generate discharge detection results for the variable frequency motor under test based on spatial electromagnetic signals.

[0066] Specifically, the ultra-high frequency antenna is used to collect spatial electromagnetic signals, which are then connected to an oscilloscope via a high-pass filter. The control module can automatically identify partial discharges by communicating with the oscilloscope, thus achieving automatic detection of partial discharges.

[0067] Figure 6 This is a flowchart illustrating a method for automatic detection of partial discharge in a variable frequency motor, as shown in some embodiments of this specification. Figure 6 As shown, in some embodiments, the control module is based on Figure 6 The process shown is to perform discharge detection on the variable frequency motor under test, which specifically includes: first, configuring the high-voltage pulse power supply, including parameters such as the frequency and duty cycle of the output waveform; configuring the oscilloscope measurement parameters, including parameters such as the attenuation ratio and sampling rate of the oscilloscope; stepping up the high-voltage pulse power supply, acquiring spatial electromagnetic signals, and using an algorithm to calculate the standard deviation to determine whether partial discharge has occurred; when partial discharge is detected, storing the detection result and ending the test; and ending the test when the voltage of the high-voltage pulse power supply reaches the voltage set value.

[0068] In some embodiments, the control module generates a discharge detection result corresponding to the variable frequency motor under test based on spatial electromagnetic signals, which may include:

[0069] Whether a discharge has occurred is determined by calculating the standard deviation of the spatial electromagnetic signal;

[0070] When power generation is detected, the discharge test ends and the discharge test result corresponding to the variable frequency motor under test is generated.

[0071] In some embodiments, the control module can calculate the standard deviation of the electromagnetic signal in the space based on the following formula:

[0072]

[0073] Wherein, σ(t) j The standard deviation of N spatial electromagnetic signals at point j, where N is the total number of spatial electromagnetic signals, x(t) i (j) The value of the i-th spatial electromagnetic signal at point j. Let J be the average of N spatial electromagnetic signals at point j.

[0074] Understandably, since the initial interference of power electronic devices remains almost constant, the spatial electromagnetic signals are nearly uniform in the absence of partial discharge, and therefore the standard deviation of the spatial electromagnetic signals hardly changes. However, at the moment of partial discharge, the spatial electromagnetic signals undergo a sudden change, and the standard deviation of the spatial electromagnetic signals also changes abruptly. The occurrence of partial discharge can be determined by calculating the standard deviation of the spatial electromagnetic signals. Specifically, this involves: collecting N spatial electromagnetic signals, calculating the standard deviation of all spatial electromagnetic signals from the first point to the last point M (where M is the number of data points in a spatial electromagnetic signal), and determining whether these M standard deviations undergo a sudden change to determine if partial discharge has occurred.

[0075] Figure 4 This is a structural block diagram of the control module shown in some embodiments of this specification, such as... Figure 4 The diagram illustrates examples of hardware devices that can be applied to various aspects of the present invention. The control module is intended to represent various forms of digital electronic computer devices, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The control module can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0076] like Figure 4 As shown, the control module includes a computing unit that can perform various appropriate actions and processes based on a computer program stored in read-only memory (ROM) or loaded from a storage unit into random access memory (RAM). The RAM can also store various programs and data required for device operation. The computing unit, ROM, and RAM are interconnected via a bus. Input / output (I / O) interfaces are also connected to the bus.

[0077] Multiple components in the control module are connected to the I / O interface, including: an input unit, an output unit, a storage unit, and a communication unit. The input unit can be any type of device capable of inputting information to the control module. It can receive input numerical or character information and generate key signal inputs related to user settings and / or function control of the control module. The output unit can be any type of device capable of presenting information and may include, but is not limited to, a display, speaker, video / audio output terminal, vibrator, and / or printer. The storage unit may include, but is not limited to, a hard disk and an optical disk. The communication unit allows the control module to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks, and may include, but is not limited to, modems, network interface cards, infrared communication devices, wireless communication transceivers, and / or chipsets, such as Bluetooth™ devices, WiFi devices, WiMax devices, cellular communication devices, and / or the like.

[0078] A computing unit can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of computing units include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. The computing unit performs the various methods and processes described above.

[0079] Figure 5 This is a flowchart illustrating a method for automatic partial discharge detection of a variable frequency motor, based on some embodiments of this specification. This method can perform a discharge test on the variable frequency motor under test using the aforementioned pulse power supply. Figure 5 As shown, the method for automatic detection of partial discharge in variable frequency motors may include the following steps.

[0080] Step 510: Obtain pulse waveform parameters;

[0081] Step 520: Ground the casing of the variable frequency motor to be tested, electrically connect the first phase of the variable frequency motor to be tested to the first pulse power supply, and electrically connect both the first phase and the second phase of the variable frequency motor to be tested to the second pulse power supply.

[0082] Step 530: Generate the first pulse power supply and the second pulse power supply corresponding to the pulse parameters based on the pulse waveform parameters, and perform discharge detection on the variable frequency motor to be tested.

[0083] Step 540: During the discharge detection of the variable frequency motor under test by the first pulse power supply and the second pulse power supply, spatial electromagnetic signals are collected.

[0084] Step 550: Generate the discharge detection result corresponding to the variable frequency motor under test based on the spatial electromagnetic signal.

[0085] For more details on the method for automatic detection of partial discharge in variable frequency motors, please refer to [link to relevant documentation]. Figures 1-4 and Figure 6 The relevant descriptions will not be repeated here.

[0086] The basic concepts have been described above. Obviously, for those skilled in the art, the detailed disclosure above is merely illustrative and does not constitute a limitation of this specification. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this specification. Such modifications, improvements, and corrections are suggested in this specification and therefore remain within the spirit and scope of the exemplary embodiments described herein.

[0087] Furthermore, this specification uses specific terms to describe embodiments thereof. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic associated with at least one embodiment of this specification. Therefore, it should be emphasized and noted that references to "an embodiment," "one embodiment," or "an alternative embodiment" in different locations throughout this specification do not necessarily refer to the same embodiment. Moreover, certain features, structures, or characteristics in one or more embodiments of this specification can be appropriately combined.

[0088] Furthermore, unless expressly stated in the claims, the order of processing elements and sequences, the use of numbers and letters, or other names described in this specification are not intended to limit the order of the processes and methods described herein. Although various examples have been discussed in the foregoing disclosure of some embodiments of the invention that are currently considered useful, it should be understood that such details are for illustrative purposes only, and the appended claims are not limited to the disclosed embodiments; rather, the claims are intended to cover all modifications and equivalent combinations that conform to the spirit and scope of the embodiments described herein. For example, while the system components described above can be implemented using hardware devices, they can also be implemented solely using software solutions, such as installing the described system on existing servers or mobile devices.

[0089] Similarly, it should be noted that, in order to simplify the description disclosed herein and thus aid in the understanding of one or more embodiments of the invention, the foregoing description of embodiments in this specification may sometimes combine multiple features into a single embodiment, drawing, or description thereof. However, this method of disclosure does not imply that the subject matter of this specification requires more features than those mentioned in the claims. In fact, the embodiments contain fewer features than all the features of a single embodiment disclosed above.

[0090] Finally, it should be understood that the embodiments described in this specification are merely illustrative of the principles of the embodiments described herein. Other variations may also fall within the scope of this specification. Therefore, alternative configurations of the embodiments described herein are intended to be illustrative rather than limiting, and are considered consistent with the teachings of this specification. Accordingly, the embodiments described herein are not limited to those explicitly introduced and described herein.

Claims

1. A pulse power supply for automatic detection of partial discharge in variable frequency motors, characterized in that, include: A high-voltage pulse power supply module is used to convert a high-voltage DC power supply into a first pulse power supply and a second pulse power supply. The voltage amplitude of the first pulse power supply is the same as that of the second pulse power supply, and the polarity of the first pulse power supply is opposite to that of the second pulse power supply. The first pulse power supply and the second pulse power supply are electrically connected to the variable frequency motor under test, and the first pulse power supply and the second pulse power supply are used to perform discharge detection on the variable frequency motor under test. The partial discharge detection module is used to collect spatial electromagnetic signals during the discharge detection of the variable frequency motor under test by the first pulse power supply and the second pulse power supply. The control module is used to acquire pulse waveform parameters and control the high-voltage pulse power supply module to generate the first pulse power supply and the second pulse power supply corresponding to the pulse waveform parameters based on the pulse waveform parameters. It is also used to generate the discharge detection result corresponding to the variable frequency motor under test based on the spatial electromagnetic signal. The casing of the variable frequency motor under test is grounded, the first phase of the variable frequency motor under test is electrically connected to the first pulse power supply, and both the first phase and the second phase of the variable frequency motor under test are electrically connected to the second pulse power supply.

2. The pulse power supply for automatic detection of partial discharge in a variable frequency motor according to claim 1, characterized in that, The high-voltage pulse power supply module includes a high-voltage input terminal, a first-order RC circuit, a first solid-state high-voltage DC switch, and a second solid-state high-voltage DC switch, which are connected in sequence. The first solid-state high-voltage DC switch is used to chop the high-voltage DC power supply based on the first trigger signal generated by the control module according to the pulse waveform parameters, and generate the first pulse power supply. The second solid-state high-voltage DC switch is used to chop the high-voltage DC power supply based on the second trigger signal generated by the control module according to the pulse waveform parameters, thereby generating the second pulse power supply.

3. A pulse power supply for automatic detection of partial discharge in a variable frequency motor according to claim 1, characterized in that, The partial discharge detection module includes an ultra-high frequency antenna, an oscilloscope, and a high frequency filter. The ultra-high frequency antenna is connected to the oscilloscope through the high frequency filter, and the control module communicates with the oscilloscope.

4. A pulse power supply for automatic detection of partial discharge in a variable frequency motor according to claim 1, characterized in that, The pulse waveform parameters include at least the pulse power amplitude, frequency, and duty cycle.

5. A pulse power supply for automatic detection of partial discharge in a variable frequency motor according to claim 2, characterized in that, A high-voltage relay is connected in series between the high-voltage input terminal and the first-order RC circuit. The control module is also used to control the high-voltage relay to disconnect the connection between the high-voltage input terminal and the first-order RC circuit when the high-voltage DC power supply is short-circuited.

6. A pulse power supply for automatic detection of partial discharge in a variable frequency motor according to claim 2 or 5, characterized in that, The high-voltage input terminal includes a high-voltage DC power supply connection port and a high-voltage energy storage capacitor.

7. A method for automatic detection of partial discharge in a variable frequency motor, characterized in that, The discharge test of the variable frequency motor under test based on the pulse power supply according to any one of claims 1-6 includes the following steps: Obtain pulse waveform parameters; The casing of the variable frequency motor under test is grounded, the first phase of the variable frequency motor under test is electrically connected to the first pulse power supply, and both the first phase and the second phase of the variable frequency motor under test are electrically connected to the second pulse power supply. Based on the pulse waveform parameters, a first pulse power supply and a second pulse power supply corresponding to the pulse waveform parameters are generated to perform discharge detection on the variable frequency motor to be tested. During the discharge detection of the variable frequency motor under test by the first pulse power supply and the second pulse power supply, spatial electromagnetic signals are collected. The discharge detection result corresponding to the variable frequency motor to be tested is generated based on the spatial electromagnetic signal.

8. The method for automatic detection of partial discharge in a variable frequency motor according to claim 7, characterized in that, The step of generating the discharge detection result corresponding to the variable frequency motor under test based on the spatial electromagnetic signal includes: Whether a discharge has occurred is determined by calculating the standard deviation of the spatial electromagnetic signal. When a discharge is detected, the discharge test ends and the discharge detection result corresponding to the variable frequency motor under test is generated.

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