Ceramic insulator intelligent sensor and partial discharge detection method

Abstract

The invention discloses a ceramic insulator intelligent sensor and a partial discharge detection method, the intelligent sensor comprises a sensor housing, a circuit board and a high-voltage charged sensor, the sensor housing is internally provided with the circuit board, the circuit board is connected with the high-voltage charged sensor, and the high-voltage charged sensor is internally provided with a ceramic capacitor and a detection impedance; a power management module is arranged in the circuit board; the power management module is connected with the main control circuit module, the main control circuit module is connected with the data acquisition and processing module, and the main control circuit module is connected with a LoRa wireless communication module. The capacitance value of the ceramic capacitor is calculated through an improved Romberg numerical integral iterative calculation formula, the detection impedance is adjusted based on the capacitance value, a high-frequency current component in the ceramic capacitor flows into the adjusted detection impedance, and a pulse voltage signal is generated on the detection impedance. And the pulse voltage signal is transmitted to an upper computer to judge whether the switch cabinet has a partial discharge phenomenon.

Description

Technical Field

[0001] The present invention relates to the technical field of defect diagnosis in switch cabinets and ring main units, and is a ceramic insulator intelligent sensor and a partial discharge detection method. Background Art

[0002] A high-voltage live display device is a device that transmits the signal of whether a high-voltage live body is energized to a light-emitting or sound element to display the energized state of the live body, and at the same time locks the grounding knife switch and the operation of the grid door to prevent misoperation. It is generally equipped with power equipment such as high-voltage switch cabinets and ring main units.

[0003] The high-voltage live display device mainly consists of two parts: a sensing unit and a display unit. The main body of the sensor unit uses a ceramic capacitor as the core rod, and the outer shell is cast with epoxy resin, or an insulator made of porcelain is used as the outer shell. This device obtains the energy required by the display through the ceramic induction capacitance voltage division principle, and uses a neon lamp to display the energized state of the electrical equipment at the installation position, with the characteristic of passive display.

[0004] In recent years, some scholars have proposed that the ceramic capacitor in the sensing unit can provide a current path for the high-frequency pulse current generated by partial discharge. The pulse current acts on the detection impedance to generate a pulse voltage, and the discharge of the high-voltage switch cabinet can be judged through this voltage.

[0005] However, it is found in practice that for the live display devices in switch cabinets and ring main units, due to different processing technologies selected by each manufacturing factory, there are great differences in the internal ceramic capacitance values, and the specific capacitance values range from 15 pF to 300 pF.

[0006] However, for different ceramic capacitor capacitances, when designing the data acquisition circuit, it is necessary to select a suitable detection impedance. Otherwise, it will affect the voltage and current distribution in the circuit, resulting in the brightness of the live indicator being affected. In severe cases, the indicator will go out, causing serious consequences. At the same time, when there is partial discharge in the switch cabinet, there are low-frequency current components and high-frequency current components in the ceramic capacitor. For the unadjusted detection impedance, both the low-frequency current component and the high-frequency current component will flow into the detection impedance, affecting the sensitivity of the partial discharge monitoring function.

[0007] The present invention calculates the capacitance of the ceramic capacitor with unknown capacitance through the improved Romberg numerical integration iterative calculation formula, and then adjusts a suitable detection impedance, thereby avoiding the influence on the brightness of the live indicator. When there is partial discharge in the switch cabinet, the high-frequency current component in the current output by the ceramic capacitor flows into the adjusted detection impedance, and a pulse voltage signal is generated on the detection impedance. The pulse voltage signal is sampled, amplified, filtered, and transmitted to the upper computer through the data acquisition and processing module to determine whether there is partial discharge in the switch cabinet. Summary of the Invention

[0008] In view of the deficiencies of the prior art, the present invention provides an intelligent sensor for ceramic insulators and a partial discharge detection method to solve the problems raised in the above-mentioned background art.

[0009] To achieve the above object, the present invention provides the following technical solution: An intelligent sensor for ceramic insulators includes a sensor housing, a circuit board, and a high-voltage live sensor; A circuit board is provided inside the sensor housing. A high-voltage live sensor is connected to the circuit board, and a ceramic capacitor and a detection impedance are provided inside the high-voltage live sensor; A power management module is provided inside the circuit board; The power management module is connected to the main control circuit module, and the main control circuit module calculates the capacitance value of the ceramic capacitor through an improved Romberg numerical integration iterative calculation formula; The main control circuit module is connected to the data acquisition and processing module, and the data acquisition and processing module adjusts the magnitude of the detection impedance according to the capacitance value of the ceramic capacitor; The high-voltage live sensor is used to allow the high-frequency current component in the current output by the ceramic capacitor to flow into the adjusted detection impedance, and a pulse voltage signal is generated on the detection impedance. The data acquisition and processing module collects the pulse voltage signal and transmits it to the main control circuit module; The main control circuit module is connected to a LoRa wireless communication module, and the pulse voltage signal is transmitted to the upper computer through the LoRa wireless communication module.

[0010] Further, a coaxial cable is connected to the sensor housing, and the other end of the coaxial cable is connected to the high-voltage live sensor.

[0011] Further, one end of the ceramic capacitor is respectively connected to one end of the switch cabinet and one end of the busbar, and the other end of the ceramic capacitor is respectively connected to one end of the live indicator light and one end of the detection impedance; The other end of the switch cabinet is respectively connected to the other end of the busbar, the other end of the live indicator light, the grounding end, and one end of the switch; The other end of the switch is connected to the other end of the detection impedance.

[0012] Further, a partial discharge detection method for an intelligent sensor of a ceramic insulator includes the following steps: The power management module steps down the power input to the switch cabinet and inputs the stepped-down power into the main control circuit module; The main control circuit module calculates the capacitance value of the ceramic capacitor through an improved Romberg numerical integration iterative calculation formula; The main control circuit module sends instructions to the data acquisition and processing module according to the capacitance value of the ceramic capacitor. The data acquisition and processing module adjusts the magnitude of the detection impedance controlled by the switch according to the capacitance value of the ceramic capacitor; the high-frequency current component in the current output by the ceramic capacitor flows into the adjusted detection impedance, and a pulse voltage signal is generated on the detection impedance. The data acquisition and processing module samples, amplifies, and filters the pulse voltage signal, and through the wireless communication module transmits the collected pulse voltage signal to the host computer, and determines whether partial discharge occurs in the switch cabinet according to the pulse voltage signal.

[0013] Furthermore, the capacitance value of the ceramic capacitor is calculated by an improved Romberg numerical integration iterative calculation formula. The specific process is as follows: Collect the change amount of the input voltage value of the main control circuit module at fixed time intervals; Divide the change amount of the voltage value by the sampling standard resistor R0 to obtain the current value at fixed time intervals; Calculate the current value to obtain the charge stored in the ceramic capacitor of the high-voltage live sensor ; represents the differential of time; represents the termination time; represents the starting time; represents the current value at time t; Use the improved Romberg numerical integration iterative calculation formula to solve the charge stored in the ceramic capacitor of the high-voltage live sensor , and the improved Romberg numerical integration iterative calculation formula is as follows: ; In the formula, represents the initial value of the charge in the trapezoidal sequence; represents the current value at the starting time t o ; represents the current value at the termination time ; represents the charge obtained in the th iteration in the trapezoidal sequence; represents the charge obtained in the th iteration in the trapezoidal sequence; represents the current value calculated according to the index variable W and the number of iterations and ; W represents the index variable; represents the charge at the mth time point in the th iteration obtained by Richardson extrapolation; represents the charge at the mth time point in the th iteration obtained by Richardson extrapolation; represents the The electric charge at a time point; Indicates the th iteration of Richardson extrapolation, and the electric charge at a time point; ; Indicates the total number of iterations.

[0014] Furthermore, Richardson extrapolation includes the trapezoidal sequence, Simpson sequence, Cotes sequence, and Romberg sequence; the time point ; when , the calculated electric charge in the trapezoidal sequence, when , the calculated electric charge in the Simpson sequence, when , the calculated electric charge in the Cotes sequence, when , the calculated electric charge in the Romberg sequence; ; Let be the minimum bisection times, ; When , , calculate the electric charge obtained in the 1st iteration of the trapezoidal sequence ; when , , calculate the electric charge at the 1st time point obtained in the Simpson sequence , when the condition of is not met, let , and continue the iteration.

[0015] Furthermore, when , , calculate the electric charge obtained in the 2nd iteration of the trapezoidal sequence ; when , , calculate the electric charge at the 1st time point obtained in the 1st iteration of the Simpson sequence ; when , , calculate the electric charge at the 2nd time point obtained in the Cotes sequence , when the condition of is not met, let , and continue the iteration.

[0016] Furthermore, when , , calculate the electric charge obtained in the 3rd iteration of the trapezoidal sequence ; when , , calculate the electric charge at the 1st time point obtained in the 2nd iteration of the Simpson sequence ; when , When calculating the electric charge at the second time point of the first iteration of the Cotes sequence ; when , When calculating the electric charge at the third time point of the Romberg sequence ; when the condition of is not satisfied, let , and continue the iteration.

[0017] Furthermore, when , When calculating the electric charge at the -th iteration of the trapezoidal sequence ; when , When calculating the electric charge at the first time point of the -th iteration of the Simpson sequence ; when , When calculating the electric charge at the second time point of the -th iteration of the Cotes sequence ; when , When calculating the electric charge at the third time point of the -th iteration of the Romberg sequence ; when , When calculating the electric charge at the third time point of the -th iteration of the Romberg sequence ; when the accuracy requirement of is met, then , otherwise continue the iterative calculation until the accuracy requirement of is met; e represents the base of the natural logarithm; After solving the electric charge Q stored in the ceramic capacitor of the high-voltage live sensor, according to the formula: , the capacitance value of the ceramic capacitor is obtained ; U represents the voltage across the ceramic capacitor.

[0018] Furthermore, to determine whether there is a partial discharge phenomenon in the switch cabinet, the specific process is as follows: When there is a partial discharge in the switch cabinet, there are low-frequency current components and high-frequency current components in the current flowing out of the ceramic capacitor; through the adjusted detection impedance, ensure that the low-frequency current components do not flow into the adjusted detection impedance, and the high-frequency current components flow into the adjusted detection impedance; When the high-frequency current component flows through the adjusted detection impedance, a pulse voltage signal is generated on the detection impedance. The data acquisition and processing module samples, amplifies, and filters the pulse voltage signal, and transmits the acquired pulse voltage signal to the upper computer through the LoRa wireless communication module, and determines whether partial discharge occurs in the switch cabinet according to the pulse voltage signal.

[0019] Compared with the existing technologies, the present invention has the following beneficial effects: The present invention calculates the capacitance value of the ceramic capacitor through the improved Romberg numerical integration iteration calculation formula, and then adjusts the magnitude of the detection impedance according to the capacitance value of the ceramic capacitor, thereby avoiding the influence on the brightness of the live indicator light; when partial discharge occurs in the switch cabinet, the high-frequency current component in the current output by the ceramic capacitor flows into the adjusted detection impedance, and a pulse voltage signal is generated on the detection impedance. The pulse voltage signal is transmitted to the upper computer through the LoRa wireless communication module, and it is determined whether partial discharge occurs in the switch cabinet according to the pulse voltage signal; the beneficial result is that there is no need to prospect the site in advance, nor to perform on-site calibration and debugging during installation. On the premise of not knowing the capacitance value of the ceramic capacitor, the detection impedance is adaptively adapted, the problem of the extinguishing of the live indicator light is solved, and the on-site installation and construction efficiency is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic structural diagram of the ceramic insulator intelligent sensor of the present invention.

[0021] Figure 2 It is a partial discharge detection circuit diagram of the switch cabinet of the present invention.

[0022] Reference numerals: 11, sensor housing; 112, circuit board; 13, power management module; 14, main control circuit module; 115, LoRa wireless communication module; 16, data acquisition and processing module; 17, external power supply; 18, LoRa antenna; 19, high-voltage live sensor; 110, coaxial cable. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] As Figure 1 shown, the present invention provides a technical solution: a ceramic insulator intelligent sensor, including a sensor housing 11, a circuit board 112, and a high-voltage live sensor 19; A circuit board 112 is arranged inside the sensor housing 11, a high-voltage live sensor 19 is connected to the circuit board 112, and a ceramic capacitor and a detection impedance are arranged inside the high-voltage live sensor 19 ; A power management module 13 is arranged inside the circuit board 112; The power management module 13 is connected to the main control circuit module 14, and the main control circuit module 14 calculates the capacitance value of the ceramic capacitor through the improved Romberg numerical integration iteration calculation formula; The main control circuit module 14 is connected to the data acquisition and processing module 16, and the data acquisition and processing module 16 adjusts the detection impedance according to the capacitance value of the ceramic capacitor. Magnitude; The high-voltage live sensor 19 is used to let the high-frequency current component in the current output by the ceramic capacitor flow into the adjusted detection impedance. In the detection impedance, A pulse voltage signal is generated on it, and the data acquisition and processing module 16 collects the pulse voltage signal and transmits it to the main control circuit module 14; The main control circuit module 14 is connected to the LoRa wireless communication module 115, and the pulse voltage signal is transmitted to the host computer through the LoRa wireless communication module 115.

[0024] Wherein, the other end of the power management module 13 is connected to the external power supply 17; the other end of the LoRa wireless communication module 115 is connected to the LoRa antenna 18; a coaxial cable 110 is connected to the sensor housing 11, and the other end of the coaxial cable 110 is connected to the high-voltage live sensor 19.

[0025] As Figure 2 Shown, one end of the ceramic capacitor is respectively connected to one end of the switch cabinet and one end of the busbar, and the other end of the ceramic capacitor is respectively connected to one end of the live indicator light and one end of the detection impedance. Connection; The other end of the switch cabinet is respectively connected to the other end of the busbar, the other end of the live indicator light, the grounding end GND, and one end of the switch k. ， Connection; Switch k ， The other end is connected to the other end of the detection impedance; the voltage across both ends of the detection impedance is U. Connection; the detection impedance The voltage across both ends is U. d .

[0026] Among them, a partial discharge detection method for a ceramic insulator intelligent sensor includes the following steps: The power management module 13 steps down the power input to the switch cabinet and inputs the stepped-down power into the main control circuit module 14; The main control circuit module 14 calculates the capacitance value of the ceramic capacitor through an improved Romberg numerical integration iterative calculation formula; The main control circuit module 14 sends an instruction to the data acquisition and processing module 16 according to the capacitance value of the ceramic capacitor, and the data acquisition and processing module 16 adjusts the switch k according to the capacitance value of the ceramic capacitor. ， To control the detection impedance Magnitude; let the high-frequency current component in the current output by the ceramic capacitor flow into the adjusted detection impedance. In the detection impedance, A pulsed voltage signal is generated thereon, and the pulsed voltage signal is sampled, amplified, and filtered by the data acquisition and processing module 16. The acquired pulsed voltage signal is transmitted to the host computer through the LoRa wireless communication module 115, and whether partial discharge occurs in the switch cabinet is determined according to the pulsed voltage signal.

[0027] Among them, the capacitance value of the ceramic capacitor is calculated by an improved Romberg numerical integration iterative calculation formula. The specific process is as follows: Collect the change amount of the voltage value at the input end of the main control circuit module 14 at fixed time intervals; Divide the change amount of the voltage value by the sampling standard resistance to obtain the current value at fixed time intervals; Calculate the current value to obtain the electric charge stored in the ceramic capacitor of the high-voltage live sensor 19 ; represents the differential of time; represents the termination time; represents the starting time; represents the current value at time; Use the improved Romberg numerical integration iterative calculation formula to solve the electric charge stored in the ceramic capacitor of the high-voltage live sensor 19 The improved Romberg numerical integration iterative calculation formula is as follows: ; In the formula, represents the initial value of the electric charge in the trapezoidal sequence; represents the starting time of the current value; represents the termination time of the current value; represents the th iteration of the electric charge obtained in the trapezoidal sequence; represents the th iteration of the electric charge obtained in the trapezoidal sequence; represents between and the current value calculated according to the index variable W and the number of iterations ; W represents the index variable; represents the electric charge at the mth time point of the th iteration obtained by Richardson extrapolation; represents the electric charge at the th iteration and the th time point obtained by Richardson extrapolation; represents the electric charge at the th iteration and the The charge amount at a time point; ; Represents the total number of iteration times.

[0028] Among them, Richardson extrapolation includes the trapezoidal sequence, Simpson sequence, Cotes sequence, and Romberg sequence; the time point ; when The charge amount calculated in the trapezoidal sequence, when The charge amount calculated in the Simpson sequence, when The charge amount calculated in the Cotes sequence, when The charge amount calculated in the Romberg sequence; ; Let Be the minimum bisection times, ; When At, in Of the trapezoidal sequence by The calculated charge amount ; When At, in Of the Simpson sequence by The calculated charge amount , when the condition of Is not met, let , continue to iterate; Represents the charge amount obtained from the first iteration in the trapezoidal sequence; Represents the charge amount at the first time point obtained from the Simpson sequence.

[0029] Among them, when At, in Of the trapezoidal sequence by The calculated charge amount ; When At, in Of the Simpson sequence by The calculated charge amount ; When At, in Of the Cotes sequence by The calculated charge amount ; When the condition of Is not met, let , continue to iterate; Represents the charge amount obtained from the second iteration in the trapezoidal sequence; Represents the charge amount at the first time point of the first iteration obtained from the Simpson sequence; Represents the charge amount at the second time point obtained from the Cotes sequence.

[0030] Among them, when is the case, the electric charge obtained by calculation from in the trapezoidal sequence of is ; when is the case, the electric charge obtained by calculation from in the Simpson sequence of is ; when is the case, the electric charge obtained by calculation from in the Cotes sequence of is ; when is the case, the electric charge obtained by calculation from in the Romberg sequence of is ; when the condition of is not met, let , and continue the iteration; represents the electric charge obtained in the 3rd iteration in the trapezoidal sequence; represents the electric charge at the 1st time point in the 2nd iteration obtained in the Simpson sequence; represents the electric charge at the 2nd time point in the 1st iteration obtained in the Cotes sequence; represents the electric charge at the 3rd time point obtained in the Romberg sequence.

[0031] Among them, when is the case, the electric charge obtained by calculation from in the trapezoidal sequence of is ; when is the case, the electric charge obtained by calculation from in the Simpson sequence of is ; when is the case, the electric charge obtained by calculation from in the Cotes sequence of is ; when is the case, the electric charge obtained by calculation from in the Romberg sequence of is ; when is the case, the electric charge obtained by calculation from in the Romberg sequence of is ; when the accuracy requirement of is met, then , otherwise continue the iterative calculation until the accuracy requirement of is met; represents the electric charge at the kth iteration obtained in the trapezoidal sequence; Denote the electric charge at the first time point of the th iteration obtained from the Simpson sequence; Denote the electric charge at the second time point of the th iteration obtained from the Cotes sequence; Denote the electric charge at the third time point of the th iteration obtained from the Romberg sequence; Denote the electric charge at the third time point of the th iteration obtained from the Romberg sequence; e represents the base of the natural logarithm; After solving the electric charge Q stored in the ceramic capacitor of the high-voltage live sensor 19, according to the formula: , the capacitance value of the ceramic capacitor is obtained; U represents the voltage across the ceramic capacitor.

[0032] Among them, the specific process of determining whether partial discharge occurs in the switch cabinet is as follows: When partial discharge occurs in the switch cabinet, there are low-frequency current components and high-frequency current components in the current flowing out of the ceramic capacitor; through the adjusted detection impedance , ensure that the low-frequency current component does not flow into the adjusted detection impedance , and the high-frequency current component flows into the adjusted detection impedance ; When the high-frequency current component flows through the adjusted detection impedance , a pulse voltage signal is generated on the detection impedance . The pulse voltage signal is sampled, amplified, and filtered by the data acquisition and processing module 16, and the collected pulse voltage signal is transmitted to the upper computer through the LoRa wireless communication module 115. Whether partial discharge occurs in the switch cabinet is determined according to the pulse voltage signal ; The present invention solves the situation of the voltage and current distribution of the ceramic capacitor through the adjusted detection impedance , protects the live indicator light, and thus avoids the influence on the brightness of the live indicator light.

[0033] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An intelligent sensor for ceramic insulators, characterized in that, It includes a sensor housing, a circuit board and a high-voltage live sensor; A circuit board is arranged inside the sensor housing, a high-voltage live sensor is connected to the circuit board, and a ceramic capacitor and a detection impedance are arranged inside the high-voltage live sensor; A power management module is arranged inside the circuit board; The power management module is connected to the main control circuit module, and the main control circuit module calculates the capacitance value of the ceramic capacitor through an improved Romberg numerical integration iteration calculation formula; The main control circuit module is connected to the data acquisition and processing module, and the data acquisition and processing module adjusts the size of the detection impedance according to the capacitance value of the ceramic capacitor; The high-voltage live sensor is used to make the high-frequency current component in the current output by the ceramic capacitor flow into the adjusted detection impedance, a pulse voltage signal is generated on the detection impedance, and the data acquisition and processing module collects the pulse voltage signal and transmits it to the main control circuit module; The main control circuit module is connected with a LoRa wireless communication module, and transmits the pulse voltage signal to the upper computer through the LoRa wireless communication module.

2. The intelligent sensor for a ceramic insulator according to claim 1, characterized in that: A coaxial cable is connected to the sensor housing, and the other end of the coaxial cable is connected to the high-voltage live sensor.

3. The intelligent sensor for a ceramic insulator according to claim 2, characterized in that: One end of the ceramic capacitor is respectively connected to one end of the switch cabinet and one end of the busbar, and the other end of the ceramic capacitor is respectively connected to one end of the live indicator light and one end of the detection impedance; The other end of the switch cabinet is respectively connected to the other end of the busbar, the other end of the live indicator light, the grounding end and one end of the switch; The other end of the switch is connected to the other end of the detection impedance.

4. A partial discharge detection method for the ceramic insulator intelligent sensor according to any one of claims 1-3, characterized in that, It includes the following steps: The power management module steps down the power input to the switch cabinet and inputs the stepped-down power into the main control circuit module; The main control circuit module calculates the capacitance value of the ceramic capacitor through an improved Romberg numerical integration iteration calculation formula; The main control circuit module sends an instruction to the data acquisition and processing module according to the capacitance value of the ceramic capacitor, and the data acquisition and processing module adjusts the switch to control the size of the detection impedance according to the capacitance value of the ceramic capacitor; make the high-frequency current component in the current output by the ceramic capacitor flow into the adjusted detection impedance, a pulse voltage signal is generated on the detection impedance, the pulse voltage signal is sampled, amplified and filtered through the data acquisition and processing module, and the collected pulse voltage signal is transmitted to the upper computer through the LoRa wireless communication module, and whether there is a partial discharge phenomenon in the switch cabinet is judged according to the pulse voltage signal.

5. A partial discharge detection method according to claim 4, characterized in that: Calculating the capacitance value of the ceramic capacitor through an improved Romberg numerical integration iteration calculation formula, the specific process is as follows: Collect the change amount of the input voltage value of the main control circuit module at a fixed time interval; Divide the change amount of the voltage value by the sampling standard resistor R0 to obtain the current value at a fixed time interval; Calculate the current value to obtain the charge stored in the ceramic capacitor of the high-voltage live sensor ; Represents the time differential; t n Represents the termination time; t o Represents the starting time; Represents the current value at time t; Use an improved Romberg numerical integration iteration calculation formula to solve the stored charge Q of the ceramic capacitor of the high-voltage live sensor. The improved Romberg numerical integration iteration calculation formula is as follows: ； In the formula, represents the initial value of the charge quantity in the trapezoidal sequence; represents the starting time t o of the current value; represents the ending time t n of the current value; represents the charge quantity obtained in the th iteration in the trapezoidal sequence; represents the charge quantity obtained in the th iteration in the trapezoidal sequence; represents the current value calculated according to the index variable W and the number of iterations o and t n ; W represents the index variable; represents the charge quantity at the mth time point in the th iteration obtained by Richardson extrapolation; represents the charge quantity at the th iteration obtained by Richardson extrapolation at the th time point; represents the charge quantity at the th iteration obtained by Richardson extrapolation at the th time point; ; represents the total number of iterations.​ 6. A partial discharge detection method according to claim 5, characterized in that: Richardson extrapolation includes trapezoidal sequence, Simpson sequence, Cotes sequence and Romberg sequence; time points m = 0, 1, 2, 3; The charge amount calculated in the trapezoidal sequence when m = 0, the charge amount calculated in the Simpson sequence when m = 1, the charge amount calculated in the Cotes sequence when m = 2, and the charge amount calculated in the Romberg sequence when m = 3; ; Let k1 be the minimum number of bisections, where k1 = 4; When k = 1 and m = 0, calculate the electric charge obtained in the first iteration of the trapezoidal sequence ; when k = 1 and m = 1, calculate the electric charge T1 at the first time point obtained from the Simpson sequence (0) , when the condition k ≥ k1 is not satisfied, let k = k + 1 and continue the iteration.

7. A partial discharge detection method according to claim 6, characterized in that: When k = 2 and m = 0, calculate the electric charge obtained in the second iteration of the trapezoidal sequence ; when k = 2 and m = 1, calculate the electric charge at the first time point in the first iteration obtained from the Simpson sequence ; when k = 2 and m = 2, calculate the electric charge at the second time point obtained from the Cotes sequence , when the condition k ≥ k1 is not satisfied, let k = k + 1 and continue the iteration.

8. A partial discharge detection method according to claim 7, characterized in that: When k = 3 and m = 0, calculate the electric charge obtained in the 3rd iteration of the trapezoidal sequence ; when k = 3 and m = 1, calculate the electric charge at the 1st time point in the 2nd iteration obtained from the Simpson sequence ; when k = 3 and m = 2, calculate the electric charge at the 2nd time point in the 1st iteration obtained from the Cotes sequence ; when k = 3 and m = 3, calculate the electric charge at the 3rd time point obtained from the Romberg sequence ; when the condition k ≥ k1 is not satisfied, let k = k + 1 and continue the iteration.

9. A partial discharge detection method according to claim 8, characterized in that: When \(k\geq4\) and \(m = 0\), calculate the charge at the \(k\)-th iteration of the trapezoidal sequence ; when \(k\geq4\) and \(m = 1\), calculate the charge at the first time point of the th iteration of the Simpson sequence ; when holds, calculate the charge at the second time point of the th iteration of the Cotes sequence ; when holds, calculate the charge at the third time point of the th iteration of the Romberg sequence ; when holds, calculate the charge at the third time point of the th iteration of the Romberg sequence ; when the accuracy requirement of is met, then , otherwise continue the iterative calculation until the accuracy requirement of is met; \(e\) represents the base of the natural logarithm; After solving the stored charge quantity Q of the ceramic capacitor of the high-voltage live sensor, according to the formula: Q = C×U, the capacitance value C of the ceramic capacitor is obtained as C = Q / U; U represents the voltage across the ceramic capacitor.

10. The partial discharge detection method according to claim 9, wherein: Determine whether partial discharge occurs in the switch cabinet. The specific process is as follows: When partial discharge occurs in the switch cabinet, there are low-frequency current components and high-frequency current components in the current flowing out of the ceramic capacitor; through the adjusted detection impedance, it is ensured that the low-frequency current components do not flow into the adjusted detection impedance, and the high-frequency current components flow into the adjusted detection impedance; When the high-frequency current components flow through the adjusted detection impedance, pulse voltage signals are generated on the detection impedance. The data acquisition and processing module samples, amplifies, and filters the pulse voltage signals, and transmits the collected pulse voltage signals to the upper computer through the LoRa wireless communication module, and determines whether partial discharge occurs in the switch cabinet according to the pulse voltage signals.

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