Device for detecting dielectric loss of withstand voltage partial discharge of single-phase capacitor
By using a series resonant system and multiple measurement modules in synergy, the problems of low automation and insufficient safety protection in existing capacitor testing equipment are solved, enabling accurate measurement and efficient testing, and improving the accuracy and safety of capacitor testing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHANGHAI JIATE HIGH VOLTAGE ELECTRIC EQUIP CO LTD
- Filing Date
- 2025-05-12
- Publication Date
- 2026-05-01
AI Technical Summary
Existing capacitor testing equipment suffers from low automation, insufficient safety protection, and unstable measurement accuracy, making it difficult to meet the requirements for efficient and accurate factory testing.
It adopts a series resonant system, which includes a power supply module, a contact voltage regulator, a low-voltage voltage and current measurement module, an excitation transformer, a high-voltage voltage and current measurement module, a resonant capacitor module, a dielectric loss measurement module, and a partial discharge measurement module. Through the coordinated work of multiple measurement modules, it can achieve accurate measurement and flexible adaptation. Combined with adjustable reactors and isolation measures, it reduces interference and has automated testing and data management functions.
It enables precise measurement of AC withstand voltage, partial discharge, dielectric loss, and capacitance between the electrodes of single-phase capacitors, improving the accuracy and stability of the measurement, enhancing the versatility and safety of the equipment, and improving testing efficiency and data management convenience.
Smart Images
Figure CN224190166U_ABST
Abstract
Description
A single-phase capacitor withstand voltage partial discharge dielectric loss detection device Technical Field
[0001] This utility model relates to capacitance detection, specifically to a device for detecting the dielectric loss of a single-phase capacitor with withstand voltage partial discharge. Background Technology
[0002] Existing capacitor testing equipment suffers from low automation, insufficient safety protection, and unstable measurement accuracy. For example, manual tuning and voltage boosting processes are susceptible to human error, and safety interlocks and discharge devices have slow response times, making it difficult to meet the requirements of efficient and accurate factory testing. Therefore, there is an urgent need for an integrated testing device that can achieve automated testing of multiple parameters and safe and reliable operation. Summary of the Invention
[0003] This utility model provides a single-phase capacitor withstand voltage, partial discharge, and dielectric loss detection device. The detection device uses a series resonant system to perform an inter-electrode AC withstand voltage test on the capacitor under test. The series resonant system includes a power supply module, a contact voltage regulator, a low-voltage voltage and current measurement module, an excitation transformer, a high-voltage voltage and current measurement module, a resonant capacitor module, a dielectric loss measurement module, and a partial discharge measurement module connected in sequence. The excitation transformer has a first winding circuit and a second winding circuit. An adjustable reactor is connected between the excitation transformer and the high-voltage voltage and current measurement module.
[0004] The power module is connected to the contact voltage regulator to provide input power to the device;
[0005] The low-voltage voltage and current measurement module includes a low-voltage voltage and current measuring instrument and a first current transformer and a voltage transformer connected to the first winding circuit. The first current transformer and the voltage transformer are respectively connected to the current sampling terminal and the voltage sampling terminal of the low-voltage voltage and current measuring instrument.
[0006] The excitation voltage control module includes an excitation transformer and an excitation voltage controller connected to the excitation transformer.
[0007] The high voltage and current measurement module includes a high voltage and current measuring instrument, a second current transformer and a voltage divider capacitor module connected to the second winding circuit. The second current transformer and the voltage divider capacitor module are respectively connected to the current sampling terminal and the voltage sampling terminal of the high voltage and current measuring instrument.
[0008] The resonant capacitor module includes a resonant capacitor whose two ends are connected to the second winding circuit;
[0009] The dielectric loss measurement module includes a capacitor under test and a dielectric loss tester. The two ends of the capacitor under test are connected to the second winding circuit. One end of the dielectric loss tester is connected between the capacitor under test and the second winding circuit through a third current transformer, and the other end of the dielectric loss tester is connected to the second winding circuit through a fifth capacitor.
[0010] The partial discharge measurement module includes a partial discharge instrument connected to the second winding circuit via a partial discharge impedance resistor and a coupling capacitor.
[0011] Furthermore, the second winding circuit is connected to a first variable resistor and a second variable resistor, and the high voltage and current measurement module, the resonant capacitor module, the dielectric loss measurement module, and the partial discharge measurement module are all located between the first variable resistor and the second variable resistor.
[0012] Furthermore, a second resistor is connected between the adjustable reactor and the first variable resistor.
[0013] Furthermore, the adjustable reactor is equipped with three adjustable voltage levels, corresponding to different inductance ranges.
[0014] Furthermore, the voltage divider capacitor module includes a second low-voltage voltage divider capacitor and a third low-voltage voltage divider capacitor connected in series between the second winding circuits.
[0015] One end of the voltage sampling terminal of the high voltage and current measuring instrument is connected to the second winding circuit, and the other end is connected between the second low voltage dividing capacitor and the third low voltage dividing capacitor.
[0016] Furthermore, the two ends of the first winding circuit are connected to a contact voltage regulator, and a first capacitor and a first resistor are connected in series between the first winding circuits.
[0017] Furthermore, a switch is connected between the fifth capacitor, the coupling capacitor, and the second winding circuit.
[0018] Furthermore, it also includes a data unit, which is connected to the low-voltage voltage and current measurement module, the high-voltage voltage and current measurement module, the resonant capacitor module, the dielectric loss measurement module, and the partial discharge measurement module.
[0019] The advantages of this utility model are:
[0020] 1) Precise Measurement: Through the collaborative work of multiple measurement modules, precise measurements of the inter-electrode AC withstand voltage, partial discharge, dielectric loss, and capacitance of single-phase capacitors are achieved. For example, the low-voltage and high-voltage measurement modules sample and measure the voltage and current of different circuits, providing basic data for the entire test; the dielectric loss measurement module, utilizing the fifth capacitor and the third current transformer, can accurately measure the dielectric loss and capacitance of the capacitor; the partial discharge measurement module uses an electrical measurement method to accurately measure the partial discharge quantity. The cooperation of each module ensures the accuracy and reliability of the measurement results.
[0021] 2) Flexible Adaptability: The adjustable reactor has three adjustable voltage settings, corresponding to different inductance ranges. It can be adjusted according to the capacitance value of the capacitor being tested, making the device suitable for testing single-phase capacitors of various specifications. By changing the air gap of the reactor core, the inductance can be continuously adjusted, expanding the testing range of the device and improving its versatility.
[0022] 3) Strong anti-interference capability: Each measurement module is relatively independent yet works in concert, and some modules employ isolation measures to reduce mutual interference. For example, the measurement circuit is fully isolated; current and voltage signals enter the controller through the current transformer, and then are transmitted to the A / D unit through an isolation operational amplifier within the controller, effectively avoiding signal interference and improving the stability of the test.
[0023] 4) Convenient Operation and Efficient Data Management: The contact voltage regulator features multi-speed electric voltage adjustment, zero-position closing, and 0V output voltage start-up functions, facilitating voltage adjustment by operators. According to the technical documentation, the entire device also has automated testing and data management functions, automatically collecting and analyzing test data, generating test records and reports, and enabling functions such as production product qualification rate statistics, report printing, querying, storage, and uploading, thus improving testing efficiency and the convenience of data management. Attached Figure Description
[0024] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0025] Figure 1 is a circuit diagram of a single-phase capacitor withstand voltage partial discharge dielectric loss detection device according to this utility model. Detailed Implementation
[0026] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid confusion with the present invention.
[0027] To fully understand this utility model, detailed steps and structures will be presented in the following description to illustrate the technical solution of this utility model. Preferred embodiments of this utility model are described in detail below; however, in addition to these detailed descriptions, this utility model may have other embodiments.
[0028] Referring to Figure 1, this utility model provides a single-phase capacitor withstand voltage, partial discharge, and dielectric loss detection device. This device uses a series resonant system to perform an inter-electrode AC withstand voltage test on the capacitor under test. The series resonant system includes a power supply module 1, a contact voltage regulator TDGZ, a low-voltage voltage and current measurement module, an excitation transformer T1, a high-voltage voltage and current measurement module, a resonant capacitor module, a dielectric loss measurement module, and a partial discharge measurement module connected in sequence. The excitation transformer T1 has a first winding circuit and a second winding circuit. The power supply module 1, the contact voltage regulator TDGZ, and the low-voltage voltage and current measurement module are connected to the first winding circuit, while the high-voltage voltage and current measurement module, the resonant capacitor module, the dielectric loss measurement module, and the partial discharge measurement module are connected to the second winding circuit.
[0029] It should be noted that the terms "low pressure" and "high pressure" used in this article are relative concepts. That is, "low pressure" refers to the concept of low pressure relative to "high pressure," and vice versa.
[0030] An adjustable reactor L1 is connected between the excitation transformer T1 and the high-voltage voltage and current measurement module. In an optional embodiment, the adjustable reactor L1 has three adjustable voltage levels, corresponding to different inductance ranges. The technical parameters of the high-voltage adjustable reactor L1 are YTKY-140kVA / 5kV / 7.5kV / 10kV. 1) Maximum voltage for each level: 10kV, 7.5kV, 5kV. 2) Maximum current for each level: 15.5A, 23.3A, 32A. 3) Rated capacity: 140kVA. 4) Operating frequency: 50Hz. 5) Operating environment: Altitude not exceeding 1000 meters, temperature within -10~+45℃, free from vapor, dust, dirt, chemical deposits, and explosive or corrosive media. 6) Quality factor: Q≮50. 7) Partial discharge: ≤2pC. 8) Adjustable inductance and sample capacitance range:
[0031] The inductance and capacitance ranges for each gear are as follows: First gear: 20H - 1.85H (0-10kV), 0.50uF - 6.5uF; Second gear: 9.1H - 0.7H (0-7.5kV), 1.11uF - 14.4uF; Third gear: 4.1H - 0.32H (0-5kV), 2.47uF - 31.5uF. surface
[0032] 9) Cooling method: oil-immersed. 10) Maximum temperature rise ≤ 65K. 11) Reactor surface temperature: ≤ 75℃.
[0033] 12) Noise: ≤65 dB. 13) Permissible mode: Intermittent continuous operation. 14) Dimensions: Length: 1200 mm, Width: 1550 mm, Height: 1650 mm. 15) Total weight: 3200 kg.
[0034] Power Module 1
[0035] The power module 1 includes a power switch KM, which is connected to a contact voltage regulator TDGZ to provide input power to the device.
[0036] Low voltage and current measurement module
[0037] The low-voltage voltage and current measurement module includes a low-voltage voltage and current measuring instrument 2 and a first current transformer CT1 and a voltage transformer PT1 connected to the first winding circuit. The first current transformer CT1 and the voltage transformer PT1 are respectively connected to the current sampling terminal and the voltage sampling terminal of the low-voltage voltage and current measuring instrument 2.
[0038] Excitation voltage control module
[0039] The excitation voltage control module includes an excitation transformer T1 and an excitation voltage controller 3 connected to the excitation transformer T1. In one embodiment, the excitation transformer T1EXC-4kVA (integrated in an adjustable reactor) has the following operating parameters: 1) Rated input voltage: 200V. 2) Rated input current: 20A. 3) Maximum output voltage: 114V / 170V / 257V. 4) Maximum output current: 32A / 23.3A / 15.5A. 5) Rated capacity: 4kVA. 6) Permissible mode: Intermittent continuous operation. 7) Operating frequency: 50Hz. 8) Operating environment: Altitude not exceeding 1000 meters, temperature within -10 to +45℃, free from steam, dust, dirt, chemical deposits, and explosive or corrosive media. 9) Type: Oil-immersed transformer / secondary 3-tap changeover switch output. 10) Cooling method: Oil-immersed.
[0040] High voltage and current measurement module
[0041] The high voltage and current measurement module includes a high voltage and current measuring instrument 4, a second current transformer CT2 connected to the second winding circuit, and a voltage dividing capacitor module 5. The second current transformer CT2 and the voltage dividing capacitor module 5 are respectively connected to the current sampling terminal and the voltage sampling terminal of the high voltage and current measuring instrument 4.
[0042] In an optional embodiment, the voltage dividing capacitor module 5 includes a second low-voltage dividing capacitor C2 and a third low-voltage dividing capacitor C3 connected in series between the second winding circuit; one end of the voltage sampling terminal of the high-voltage voltage and current measuring instrument 4 is connected to the second winding circuit, and the other end is connected between the second low-voltage dividing capacitor C2 and the third low-voltage dividing capacitor C3. An adjustable reactor L1 is disposed between the second low-voltage dividing capacitor C2 and the excitation transformer T1.
[0043] Resonant capacitor module
[0044] The resonant capacitor module 6 includes a resonant capacitor C4 whose two ends are connected to the second winding circuit. One end of the resonant capacitor C4 is connected to the second winding circuit through a switch.
[0045] Dielectric loss measurement module 7
[0046] The dielectric loss measurement module 7 includes a capacitor under test C6 and a dielectric loss tester 8. The two ends of the capacitor under test C6 are connected to the second winding circuit. One end of the dielectric loss tester 8 is connected between the capacitor under test C6 and the second winding circuit through the third current transformer CT3. The other end of the dielectric loss tester 8 is connected to the second winding circuit through the fifth capacitor C5 and the switch.
[0047] Partial discharge measurement module 9
[0048] The partial discharge measurement module 9 includes a partial discharge instrument 11 connected to the second winding circuit via a partial discharge impedance device 10, a coupling capacitor C7, and a switch.
[0049] Furthermore, the second winding circuit is connected to a first variable resistor R3 and a second variable resistor R4. The high voltage and current measurement module, the resonant capacitor module, the dielectric loss measurement module, and the partial discharge measurement module are all located between the first variable resistor R3 and the second variable resistor R4.
[0050] In an optional embodiment, a third resistor R2 is connected between the adjustable reactor L1 and the first variable resistor R3.
[0051] In an optional embodiment, the two ends of the first winding circuit are connected to the contact voltage regulator TDGZ, and a first capacitor C1 and a first resistor R1 are connected in series between the first winding circuits.
[0052] Figure 1 shows a single-phase capacitor withstand voltage partial discharge dielectric loss detection device. It operates based on a series resonant system, with each module working collaboratively to complete multiple tests on the single-phase capacitor. The working principle is as follows:
[0053] 1. Power Supply: The power switch KM in the power module is connected to the contact voltage regulator TDGZ, providing input power to the entire device. The TDGZ allows for adjustment of the input voltage to meet various testing requirements. Its multi-speed electric voltage adjustment, zero-position closing, and 0V output voltage start-up functions facilitate voltage adjustment operations for the operator.
[0054] 2. Voltage and Current Measurement: 2.1. Low-Voltage Circuit Measurement: The first current transformer CT1 and voltage transformer PT1 in the low-voltage voltage and current measurement module sample the current and voltage of the first winding circuit, respectively, and transmit the sampled signals to the low-voltage voltage and current measuring instrument 2. These measurement data provide basic information about the low-voltage circuit for subsequent testing and analysis, helping to understand the input status of the device. 2.2. High-Voltage Circuit Measurement: The second current transformer CT2 and the voltage dividing capacitor module (composed of the second low-voltage dividing capacitor C2 and the third low-voltage dividing capacitor C3) in the second winding circuit sample the current and voltage of the high-voltage circuit, and transmit the sampled signals to the high-voltage voltage and current measuring instrument 4. The high-voltage voltage and current measuring instrument 4 accurately obtains the voltage value of the high-voltage circuit by connecting the voltage sampling terminal between the second winding circuit and the low-voltage dividing capacitors C2 and C3, thereby achieving accurate measurement of the high-voltage circuit.
[0055] 3. Excitation Voltage Control: The excitation transformer T1 in the excitation voltage control module, connected to the excitation voltage controller 3, converts the input voltage into a voltage suitable for the resonant circuit and provides power to the resonant circuit. Simultaneously, it isolates the test sample from the power supply circuit, ensuring the safety of the testing process.
[0056] 4. Resonant Circuit Operation: The adjustable reactor L1 and the resonant capacitor C4 in the resonant capacitor module form a resonant circuit. By changing the air gap in the reactor core, the inductance of the reactor is adjusted, allowing the circuit to reach a resonant state (XL = XC). In the resonant state, the current I in the circuit is in phase with the excitation transformer voltage V, and the input power is pure active power. At this time, the reactive power on the capacitor load C is Uc = QVI = QP (Q is the quality factor of the resonant circuit). This resonant characteristic enables the device to generate high voltage, meeting the requirements of capacitor withstand voltage testing. The adjustable reactor L1 has three adjustable voltage settings, corresponding to different inductance ranges, which can be adjusted according to the capacitance value of the capacitor being tested, enhancing the adaptability of the device to capacitors of different specifications.
[0057] 5. Dielectric Loss and Partial Discharge Measurement: 5.1. Dielectric Loss Measurement: In the dielectric loss measurement module, the two ends of the capacitor C6 under test are connected to the secondary winding. One end of the dielectric loss tester 8 is connected between the capacitor C6 and the secondary winding through the third current transformer CT3, and the other end is connected to the secondary winding through the fifth capacitor C5. Through this connection method, using the fifth capacitor C5 and the third current transformer CT3, the dielectric loss tester 8 can accurately measure the dielectric loss and capacitance of the capacitor. 5.2. Partial Discharge Measurement: The partial discharge instrument in the partial discharge measurement module is connected to the second winding circuit through the partial discharge impedance device 10 and the coupling capacitor C7. Using an electrical measurement method, the partial discharge instrument can accurately measure the partial discharge quantity, providing crucial data for evaluating the insulation performance of the capacitor.
[0058] 6. Data Processing and Control: During testing, data collected in real time by each measurement module is transmitted to the control system. The control system analyzes and processes this data to determine product qualification and automatically generates test records and reports. If the company has a server, data is automatically uploaded; otherwise, data is saved locally in Access database format for easy retrieval. The control system is also responsible for controlling the entire testing process, including the selection of manual or automatic testing modes, gear adjustment, voltage regulation, timing, and other operations, achieving automation and intelligence in the testing process.
[0059] 7. Safety Protection: The test area is equipped with grounding stakes with a grounding resistance of less than or equal to 0.5Ω. The equipment control panel is equipped with an emergency stop button. Before the product is removed from the workstation after testing, it is discharged through a visible inter-electrode short-circuit discharge device; the short-circuit discharge device at the withstand voltage test station automatically activates upon breakdown. The guardrail passageway in the test area is equipped with safety interlocks and warning lights. High-voltage testing cannot be carried out if personnel have not evacuated or the safety door is not closed. The fast RC absorption device on the power input side and the ARC fast breakdown protection circuit on the high-voltage side quickly cut off the power supply and automatically ground and discharge in case of abnormalities, comprehensively ensuring personnel safety and preventing secondary damage to the equipment.
[0060] In actual operation, the detection device of this utility model operates according to the following steps:
[0061] 1) Preparation Phase: The product enters the testing area, and the operator uses a barcode scanning system to read the product barcode and retrieve test information and parameters from the database; if barcode reading fails, manual input is possible. Next, the test cables are manually connected, ensuring a secure connection.
[0062] 2) Testing Phase: After starting the test, the system selects either manual or automatic mode based on the settings. In manual mode, the operator must manually select the appropriate voltage level, close the circuit breaker, adjust the voltage regulator, tune to the resonant point, and increase the voltage to the set value, fine-tuning the resonant point during the voltage increase process. Timing begins after the set value is reached. At the end of the test, the operator manually reduces the voltage and opens the circuit breaker. In automatic mode, the system automatically calculates and selects the appropriate voltage level based on the sample capacitance, closes the circuit breaker, automatically increases the voltage, tunes to the resonant point, increases the voltage to the set value, and monitors the resonant Q value. Timing begins automatically after the set value is reached. Upon completion of the test, the system automatically reduces the voltage and opens the circuit breaker.
[0063] 3) Data Processing Stage: During the test, each measurement module collects data in real time and transmits it to the control system. The control system analyzes and processes the data to determine whether the product is qualified and automatically generates test records and reports. If the company has a server, the data is automatically uploaded; if there is no server, the data is saved locally in Access database format for easy retrieval.
[0064] 4) Safety Assurance: The test area is equipped with grounding stakes with a grounding resistance of less than or equal to 0.5Ω. The equipment control panel is equipped with an emergency stop button. Before the product is removed from the workstation after testing, it is discharged through a visible inter-electrode short-circuit discharge device; the short-circuit discharge device at the withstand voltage test station automatically activates upon breakdown. The guardrail passageway in the test area is equipped with safety interlocks and warning lights. High-voltage testing cannot be carried out if personnel have not evacuated or the safety door is not closed. The fast RC absorption device on the power input side and the ARC fast breakdown protection circuit on the high-voltage side quickly cut off the power supply and automatically grounded discharge in case of abnormality, preventing personnel injury and secondary damage to the equipment.
[0065] The preferred embodiments of this utility model have been described above. It should be understood that this utility model is not limited to the specific embodiments described above. Devices and structures not described in detail herein should be understood as being implemented in a conventional manner within the art. Any person skilled in the art can make many possible variations and modifications to the technical solutions of this utility model using the disclosed methods and techniques, or modify them into equivalent embodiments with equivalent changes, without departing from the scope of the technical solution of this utility model. This does not affect the essential content of this utility model. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this utility model, without departing from the content of the technical solution of this utility model, still fall within the protection scope of the technical solution of this utility model.
Claims
1. A device for detecting the dielectric loss of a single-phase capacitor under withstand voltage partial discharge, characterized in that, The testing device employs a series resonant system to perform an inter-electrode AC withstand voltage test on the capacitor under test. The series resonant system comprises, in sequence, a power supply module, a contact voltage regulator, a low-voltage and current measurement module, an excitation transformer, a high-voltage and current measurement module, a resonant capacitor module, a dielectric loss measurement module, and a partial discharge measurement module. The excitation transformer has a first winding circuit and a second winding circuit. An adjustable reactor is connected between the excitation transformer and the high-voltage and current measurement module. The power supply module is connected to the contact voltage regulator to provide input power to the device. The low-voltage and current measurement module includes a low-voltage and current measuring instrument and a first current transformer and a voltage transformer connected to the first winding circuit. The first current transformer and the voltage transformer are respectively connected to the current sampling terminal and voltage sampling terminal of the low-voltage and current measuring instrument. The excitation voltage... The control module includes an excitation transformer and an excitation voltage controller connected to the excitation transformer; the high-voltage voltage and current measurement module includes a high-voltage voltage and current measuring instrument, a second current transformer connected to the second winding circuit, and a voltage-dividing capacitor module, the second current transformer and the voltage-dividing capacitor module being connected to the current sampling terminal and voltage sampling terminal of the high-voltage voltage and current measuring instrument, respectively; the resonant capacitor module includes a resonant capacitor with both ends connected to the second winding circuit; the dielectric loss measurement module includes a capacitor under test and a dielectric loss tester, the two ends of the capacitor under test being connected to the second winding circuit, one end of the dielectric loss tester being connected between the capacitor under test and the second winding circuit through a third current transformer, and the other end of the dielectric loss tester being connected to the second winding circuit through a fifth capacitor; the partial discharge measurement module includes a partial discharge instrument connected to the second winding circuit through a partial discharge impedance device and a coupling capacitor.
2. The single-phase capacitor withstand voltage partial discharge dielectric loss detection device as described in claim 1, characterized in that, The second winding circuit is connected to the first variable resistor and the second variable resistor. The high voltage and current measurement module, the resonant capacitor module, the dielectric loss measurement module, and the partial discharge measurement module are all located between the first variable resistor and the second variable resistor.
3. The single-phase capacitor withstand voltage partial discharge dielectric loss detection device as described in claim 2, characterized in that, A second resistor is connected between the adjustable reactor and the first variable resistor.
4. The single-phase capacitor withstand voltage partial discharge dielectric loss detection device as described in claim 1, characterized in that, The adjustable reactor is equipped with three adjustable voltage levels, corresponding to different inductance ranges.
5. The single-phase capacitor withstand voltage partial discharge dielectric loss detection device as described in claim 1, characterized in that, The voltage divider capacitor module includes a second low-voltage divider capacitor and a third low-voltage divider capacitor connected in series between the second winding circuit; one end of the voltage sampling terminal of the high-voltage voltage and current measuring instrument is connected to the second winding circuit, and the other end is connected between the second low-voltage divider capacitor and the third low-voltage divider capacitor.
6. The single-phase capacitor withstand voltage partial discharge dielectric loss detection device as described in claim 5, characterized in that, The two ends of the first winding circuit are connected to a contact voltage regulator, and a first capacitor and a first resistor are connected in series between the first winding circuits.
7. The single-phase capacitor withstand voltage partial discharge dielectric loss detection device as described in claim 1, characterized in that, A switch is connected between the fifth capacitor, the coupling capacitor, and the second winding circuit.
8. A single-phase capacitor withstand voltage partial discharge dielectric loss detection device as described in any one of claims 1-7, characterized in that, It also includes a data unit, which is connected to the low-voltage and current measurement module, the high-voltage and current measurement module, the resonant capacitor module, the dielectric loss measurement module, and the partial discharge measurement module.