Insulator leakage current monitoring system and method based on magnetoresistance effect

Abstract

The invention discloses an insulator leakage current monitoring system and method based on a magneto-resistance effect. The system comprises a current primary acquisition unit, a current secondary acquisition unit and a current secondary acquisition unit. The current primary acquisition unit is used for carrying out primary leakage current detection on the surface of an insulator; the main control module receives the primary leakage current signal and performs leakage current judgment; the main control module sends the converted signal to the fault type analysis unit; the fault type analysis unit is used for performing fault analysis on the converted signal; the main control module calls a maintenance mode according to an analysis result to carry out online fault maintenance adjustment, controls the electric leakage and electricity supplement analysis module to work when electricity supplement is needed, controls the fault current converter to work when fault current conversion is needed, and controls the fault current visual display module to display fault leakage current; and the electric leakage and electricity supplement analysis module performs electric leakage and electricity supplement operation according to the control instruction of the main control module. According to the method, insulator faults can be monitored, online analysis and processing are carried out, accurate detection of the leakage current of the insulator is realized, and the specific magnitude of the leakage current can be visually displayed.

Description

Technical Field

[0001] The present invention relates to the technical field of smart distribution networks, and in particular to a system and method for monitoring insulator leakage current based on magnetoresistance effect. Background Art

[0002] The magnetoresistance effect refers to the phenomenon in which the resistance of certain metals or semiconductors changes with an applied magnetic field. Like the Hall effect, the magnetoresistance effect is caused by the Lorentz force acting on carriers in a magnetic field. When the magnetoresistance effect reaches a steady state, the electric force acting on carriers of a certain velocity is equal to the Lorentz force. Carriers gather at both ends, generating a Hall field. Carriers slower than this velocity are deflected in the direction of the electric force, while carriers faster than this velocity are deflected in the direction of the Lorentz force. This deflection increases the drift path of the carriers. In other words, the number of carriers moving in the direction of the applied electric field decreases, thereby increasing the resistance, hence the name magnetoresistance effect.

[0003] With the continuous development of subways, tunnels involve many insulator components that form high-voltage transmission lines. However, due to factors such as the surface of insulator components becoming wet due to humid air, excessive contamination on the insulator surface, ice coating on the insulator, and zero-value insulators, a conductive layer forms on the insulator surface, causing current to flow through the insulator surface. This current is the insulator leakage current. When the insulator leakage current increases, it is inevitable that the insulator will flash over, trip, and other accidents, causing it to malfunction. Insulator leakage current can be measured directly by connecting an ammeter or voltmeter directly to the insulator and measuring the current or voltage to determine the insulator leakage current. This method is simple and easy to use, but it requires direct measurement at the fault site during a power outage, which has a significant impact on the power system. Utility model patent application number 202323359670.6 discloses an insulator leakage current monitoring device using the tunnel magnetoresistance effect. The device includes a main control module for driving a magnetoresistive current detector to measure the leakage current of an insulator. The device also drives a second magnetoresistive sensor to measure the leakage current of the insulator based on the magnitude of the leakage current measured in the first measurement. The second magnetoresistive sensor has a greater measurement accuracy than the first magnetoresistive current detector. The first magnetoresistive current detector or the second magnetoresistive current detector outputs a detection voltage signal to an operational amplifier, which amplifies the detection voltage signal. An AD conversion module converts the amplified detection voltage signal into digital detection data. The main control module acquires the detection data and processes the data. This structure uses two detection components with different detection ranges to detect leakage current. However, the device cannot guarantee the impact of magnetic field interference on the monitoring process during the detection process, ultimately affecting the detection accuracy. Furthermore, the specific magnitude of the leakage current cannot be intuitively displayed. Furthermore, the monitoring system cannot be effectively protected, its long-term stable operation cannot be guaranteed, and its service life cannot be extended. Furthermore, online analysis of insulator faults cannot be performed. Summary of the Invention

[0004] The object of the present invention is to provide a system and method for monitoring insulator leakage current based on magnetoresistance effect, which can monitor insulator leakage current and perform online analysis and intuitive display of insulator faults.

[0005] The present invention is achieved through the following technical solutions: The first invention, the first embodiment of the present invention provides an insulator leakage current monitoring system based on magnetoresistance effect, comprising: a main control module, a first magnetoresistance current detector, a second magnetoresistance current detector, an operational amplifier, and an AD conversion module; further comprising: a current initial acquisition unit, a data storage library, a first control switch, a second control switch, a fault type analysis unit, a leakage current compensation analysis module, a fault current converter, and a fault current intuitive display module; The current primary acquisition unit is used to detect the primary leakage current on the surface of the insulator and send the detected primary leakage current signal to the main control module; The data storage library is used to store preset leakage current thresholds, preset power-up thresholds and fault type reference data; The main control module receives the primary leakage current signal and performs leakage current judgment. When the preset leakage current threshold is greater than the primary leakage current, the main control module sends a control instruction to the first control switch. When the preset leakage current threshold is less than the primary leakage current and the primary leakage current is greater than zero, the main control module sends a control instruction to the second control switch. The first control switch is used to control the working state of the first magnetoresistive current detector according to the instruction of the main control module; The second control switch is used to control the working state of the second magnetoresistive current detector according to the instruction of the main control module; The first magnetoresistive current detector and the second magnetoresistive current detector are both used to detect leakage current signals outside the insulator in real time, and send the detected leakage current signals to the operational amplifier; The operational amplifier is used to amplify the leakage current signal and send the amplified signal to the AD conversion module; The AD conversion module is used to perform analog-to-digital conversion on the amplified signal and send the converted data to the main control module; The main control module sends the converted signal to the fault type analysis unit; The fault type analysis unit is used to perform fault analysis on the converted signal, obtain analysis results, and send the analysis results to the main control module; The main control module calls the maintenance mode according to the analysis results to perform online fault maintenance adjustment, and controls the leakage current replenishment analysis module to work when replenishment is needed, controls the fault current converter to work when fault current conversion is needed, and controls the fault current intuitive display module to display the fault leakage current; The leakage current replenishment analysis module performs leakage current replenishment operations according to the control instructions of the main control module; The fault current converter is used to convert the fault current into a fault leakage current; The fault current intuitive display module is used to display the fault leakage current.

[0006] Furthermore, it also includes a magnetic field detector and a magnetic field shield, and the data storage library also stores a preset magnetic field magnitude threshold. The magnetic field detector is used to detect the magnetic field magnitude of the environment to be tested and send the detected magnetic field signal to the main control module; The main control module performs magnetic field evaluation on the magnetic field signal to determine whether the magnetic field meets the requirements, and sends a shielding control signal to the magnetic field shield when the magnetic field size exceeds a preset magnetic field size threshold; The magnetic field shielding device performs magnetic field shielding according to a shielding control signal.

[0007] Furthermore, the main control module performs magnetic field evaluation on the magnetic field signal, specifically including: The magnetic field judgment formula is used to judge the magnetic field. The magnetic field judgment formula is: ; Where H is the magnetic field strength, N is the number of turns of the excitation coil, is the measured excitation current, Le is the effective magnetic path length of the test sample, and Delta is the preset magnetic field strength error setting value which is a constant.

[0008] Furthermore, the main control module receives the primary leakage current signal and performs leakage current judgment specifically including: The leakage current evaluation formula is used for judgment, and the leakage current evaluation formula is: ; Where, I is the leakage current detected, U is the voltage applied across the insulator, R is the resistance of the insulator, and I0 is the leakage current error setting value which is a constant.

[0009] Furthermore, a protection module is included, which is connected to the AD conversion module and the main control module respectively, and is used to protect the converted data from overcurrent and overvoltage.

[0010] Furthermore, it also includes a cloud storage library, which is used for cloud storage monitoring data.

[0011] Furthermore, it also includes a power module, the power module includes a wind power generation module, a charge and discharge protection module and a battery module, the charge and discharge protection module is connected to the battery module and the wind power generation module respectively; The wind power generation module is used to convert wind energy into electrical energy; The charge and discharge protection module provides overcurrent, overvoltage and overload protection for the battery during charging; The battery module is used to store the electric energy converted from wind power generation.

[0012] Furthermore, it also includes a fault process updater, which is used to update the fault type data in the data storage library in real time.

[0013] Furthermore, it also includes an alarm module and a wireless communication module. The alarm module is connected to the main control module and is used to issue an alarm reminder when an insulator leakage current fault occurs. The wireless communication module is used to send the insulator leakage current monitoring data to the fault mobile device.

[0014] In a second aspect, another embodiment of the present invention provides a method for monitoring insulator leakage current based on magnetoresistance effect, comprising: The current primary acquisition unit detects the primary leakage current on the insulator surface and sends the detected primary leakage current signal to the main control module. The data storage library stores a preset leakage current threshold, a preset power-up threshold, fault type reference data, and a magnetic field magnitude threshold; The main control module receives the primary leakage current signal and performs leakage current judgment. When the preset leakage current threshold is greater than the primary leakage current, the main control module sends a control instruction to the first control switch. When the preset leakage current threshold is less than the primary leakage current and the primary leakage current is greater than zero, the main control module sends a control instruction to the second control switch. The first control switch controls the working state of the first magnetoresistive current detector according to the instruction of the main control module; The second control switch controls the working state of the second magnetoresistive current detector according to the instruction of the main control module; The first magnetoresistive current detector and the second magnetoresistive current detector both detect leakage current signals outside the insulator in real time, and send the detected leakage current signals to the operational amplifier; The operational amplifier amplifies the leakage current signal and sends the amplified signal to the AD conversion module; The AD conversion module converts the amplified signal into digital form and sends the converted data to the main control module; The main control module sends the converted signal to the fault type analysis unit; The fault type analysis unit performs fault analysis on the converted signal, obtains analysis results, and sends the analysis results to the main control module; The main control module calls the maintenance mode according to the analysis results to make online fault maintenance adjustments, and controls the leakage current replenishment analysis module to work when replenishment is needed, controls the fault current converter to work when fault current conversion is needed, and controls the fault current intuitive display module to display the fault leakage current; The leakage current replenishment analysis unit performs leakage current replenishment operations according to the control instructions of the main control module; The fault current converter is used to convert the fault current into the fault leakage current; The fault current intuitive display module is used to display the fault leakage current.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects: An embodiment of the present invention provides a system and method for monitoring leakage current of insulators using the magnetoresistance effect. The system and method can be applied to monitoring leakage current of insulators using the tunnel magnetoresistance effect. The system can monitor insulator faults and perform online analysis and processing to achieve accurate detection of insulator leakage current and intuitively display the specific magnitude of the leakage current. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the examples. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be considered as limiting the scope. A person of ordinary skill in the art can also derive other relevant drawings based on these drawings without inventive effort. In the drawings: Figure 1 This is a schematic diagram of the connection structure of an insulator leakage current monitoring system based on magnetoresistance effect in Example 1; Figure 2 This is a schematic diagram of the connection of the power module in Example 1; Figure 3 This is a schematic diagram of the connection structure of an insulator leakage current monitoring system based on magnetoresistance effect in Example 2; Figure 4 This is a schematic diagram of the connection structure of an insulator leakage current monitoring system based on magnetoresistance effect in Example 3; Figure 5 This is a schematic diagram of the connection structure of an insulator leakage current monitoring system based on magnetoresistance effect in Example 4; Figure 6 This is a schematic diagram of the connection structure of an insulator leakage current monitoring system based on magnetoresistance effect in Example 5. DETAILED DESCRIPTION

[0017] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with examples and drawings. The exemplary embodiments of the present invention and their descriptions are only used to explain the present invention and are not intended to limit the present invention.

[0018] Example 1 See also Figure 1 This embodiment provides an insulator leakage current monitoring system based on magnetoresistance effect, including a main control module 1, a magnetoresistance current detector 1 2, a second magnetoresistance current detector 2 3, a first control switch 13, a second control switch 21, an operational amplifier 4, an AD conversion module 5, a protection module 6, a fault type analysis unit 7, a data storage library 9, a current initial acquisition unit 10, a leakage current compensation analysis unit 11, a fault current converter 14, a fault current intuitive display module 15, a magnetic field shield 16, a magnetic field detector 17, and a power supply module 12 for providing power to the device.

[0019] Wherein: the data storage library 9 is used to store the preset power replenishment threshold V, the preset leakage current threshold Q, the fault type reference data and the magnetic field magnitude threshold C. The fault type reference data includes the fault type and multiple maintenance methods and procedures corresponding to the fault type.

[0020] The current primary acquisition unit 10 is used to detect the primary leakage current on the surface of the insulator and send the detected primary leakage current signal to the main control module; The main control module 1 receives the primary leakage current signal and performs leakage current judgment. When the preset leakage current threshold is greater than the primary leakage current, the main control module 1 sends a control instruction to the first control switch. When the preset leakage current threshold is less than the primary leakage current and the primary leakage current is greater than zero, the main control module 1 sends a control instruction to the second control switch. The first control switch 13 is used to control the working state of the first magnetoresistive current detector according to the instruction of the main control module; The second control switch 21 is used to control the working state of the second magnetoresistive current detector according to the instruction of the main control module; The magnetoresistive current detector 1 2 and the magnetoresistive current detector 2 3 are both used to detect the leakage current signal outside the insulator in real time, and send the detected leakage current signal to the operational amplifier 4; The operational amplifier 4 is used to amplify the detected leakage current signal and send the amplified signal to the AD conversion module 5; The AD conversion module 5 is used to perform analog-to-digital conversion on the amplified signal and send the converted data to the main control module 1; The main control module 1 sends the converted signal to the fault type analysis unit 7; The fault type analysis unit 7 is used to perform fault analysis on the converted signal, obtain analysis results, and send the analysis results to the main control module 1; The main control module 1 calls the maintenance mode according to the analysis results to perform online fault maintenance adjustments, and controls the leakage current replenishment analysis module 11 to work when replenishment is needed, controls the fault current converter 14 to work when fault current conversion is needed, and controls the fault current intuitive display module 15 to display the fault leakage current; The leakage current replenishment analysis unit 11 performs leakage current replenishment operations according to the control instructions of the main control module; The fault current converter 14 is used to convert the acquired fault current information into a fault leakage current; The fault current visual display module 15 is used to visually display the acquired fault leakage current; The measurement accuracy of the magnetoresistive current detector 2-3 is greater than that of the magnetoresistive current detector 1-2. The current initial acquisition unit 10 is connected to the main control module 1, and the main control module 1 is electrically connected to the data storage library 9. The magnetoresistive current detector 1-2 and the magnetoresistive current detector 2-3 are both connected to the operational amplifier 4. The output end of the operational amplifier 4 is electrically connected to the main control module 1 through the AD conversion module 5, which is used to convert the amplified detection voltage signal into digital detection data and perform data processing; and the main control module 1 is electrically connected to the magnetoresistive current detector 1-2 through the first control switch 13, and the main control module 1 is electrically connected to the magnetoresistive current detector 2-3 through the second control switch 21. A protection module 6 is also connected between the AD conversion module 5 and the main control module 1. The main control module 1 is respectively connected to the power supply module 12, the fault current converter 14, the fault current intuitive display module 15, the magnetic field detector 17, the magnetic field shield 16, and the fault type analysis unit 7.

[0021] The fault type analysis unit 7 is used to analyze the fault type of the insulator and then send it to the main control module 1, and automatically call the preferred maintenance method process according to the preset fault type reference data; the leakage current replenishment analysis module 11 is used to replenish the power of the insulator circuit while the insulator is being maintained when the real-time leakage current of the insulator is lower than the preset replenishment threshold V; the power supply module 12 is also electrically connected to the insulator circuit.

[0022] The magnetic field detector 17 is used to detect the magnetic field strength of the test environment and send it to the main control module 1 for magnetic field strength comparison. Then, the magnetic field is judged according to the following magnetic field evaluation formula to determine whether the magnetic field meets the requirements. If it meets the requirements, no processing is performed. If it exceeds the preset magnetic field strength threshold C, the magnetic field shielding device 16 is activated to perform magnetic field shielding. Among them, the magnetic field evaluation formula is as follows: ; Where H is the magnetic field strength in A / m; N is the number of turns of the excitation coil; is the excitation current measurement value, in A; Le is the effective magnetic path length of the test sample, in m; Delta is the preset magnetic field strength error setting value which is a constant.

[0023] When the current primary acquisition unit 10 detects the insulator current, it determines which type of leakage current the leakage current belongs to according to the leakage current evaluation formula. The specific method is as follows: S1. The evaluation formula based on leakage current is as follows: ; Where, I is the leakage current detected, U is the voltage applied across the insulator, and R is the resistance of the insulator; I0 is the leakage current error setting value, which is a constant; S2. Then, the leakage current I and the preset leakage current threshold Q are determined. When the preset leakage current threshold Q is greater than the leakage current I, it indicates that the leakage current is too large, and the second control switch 21 connected to the magnetoresistive current detector 2 is activated. If the preset leakage current threshold Q is less than the leakage current I, and the leakage current I is greater than zero, the first control switch 13 connected to the magnetoresistive current detector 2 is activated.

[0024] The leakage current replenishment analysis module 11 is used to determine in real time that the leakage current is lower than the preset replenishment threshold V according to the leakage current situation. When the insulator is maintained, the power supply module 12 can be turned on to replenish the power to the insulator circuit.

[0025] like Figure 2 As shown, the power supply module 12 includes a battery pack module 121, a charge and discharge protection module 123 and a wind power generation module 122. The battery pack module 121 and the wind power generation module 122 are respectively connected to the charge and discharge protection module 123. The wind power generation module 122 is used to realize wind power generation and convert it into electrical energy to charge the battery pack module 121 through the charge and discharge protection module 123. The charge and discharge protection module 123 is used to realize overcurrent, overvoltage and overload protection operations when the battery pack module 121 is charging.

[0026] The specific working principle of the present invention is as follows: First, when the insulator current is detected by the current initial acquisition unit 10, the leakage current I is obtained according to the leakage current judgment formula, and the situation of the leakage current I and the preset leakage current threshold Q is judged. When the preset leakage current threshold Q is greater than the leakage current I, it means that the leakage current is too large, and the second control switch 21 connected to the magnetoresistive current detector 23 is started to work; the magnetoresistive current detector 23 detects the real-time leakage current outside the insulator, and then sends it to the operational amplifier 4 for signal amplification. The amplified detection voltage signal is converted into digital detection data through the AD conversion module 5 and sent to the main control module 1 after data processing. After the main control module 1 obtains the leakage current signal, it calls the fault type analysis unit 7 and the data stored in the data storage library 9. The stored fault type reference data is used to analyze the fault type of the insulator and then send it to the main control module 1, and automatically call the preferred maintenance method process according to the preset fault type reference table; to carry out online fault maintenance adjustment, and at the same time drive the leakage current compensation analysis module 11 to work, and when the real-time leakage current of the insulator is lower than the preset compensation threshold V, the insulator circuit is compensated while the insulator is being maintained. While detecting the leakage current, the magnetic field size of the test environment is detected by the magnetic field detector 17, and sent to the main control module 1 for magnetic field size comparison, and then the magnetic field is judged whether it meets the requirements according to the following magnetic field evaluation formula. If it meets the requirements, no processing is performed. If it exceeds the preset magnetic field size threshold C, the magnetic field shielding device 16 is started to work for magnetic field shielding; If the preset leakage current threshold Q is less than the leakage current I, and the leakage current I is greater than zero, the first control switch 13 connected to the magnetoresistive current detector 2 is started to work, and the magnetoresistive current detector 2 detects the real-time leakage current outside the insulator, and then sends it to the operational amplifier 4 for signal amplification. The amplified detection voltage signal is converted into digital detection data through the AD conversion module 5 and sent to the main control module 1 after data processing. After the main control module 1 obtains the leakage current signal, it calls the fault type analysis unit 7 and the fault type reference table stored in the data storage library 9 to analyze the fault type of the insulator and then send it to the main control module 1, and automatically calls the preferred maintenance method process according to the preset fault type reference table; to perform online fault maintenance adjustment; and uses the fault current converter 14 to convert the acquired fault current information into fault leakage current and then send it to the main control module 1, which is visually displayed through the fault current intuitive display module 15.

[0027] The embodiment of the present invention provides an insulator leakage current monitoring system based on the magnetoresistance effect. It can be applied to the leakage current monitoring of insulators based on the tunnel magnetoresistance effect, can realize insulator fault monitoring, and can perform online analysis and processing, realize accurate detection of leakage current, and can also intuitively display the specific size of the leakage current. In addition, by adding a magnetic field detector in conjunction with a magnetic field shield, the leakage current monitoring system can avoid the influence of magnetic field interference on the detection during the detection process. By adding a protection module, safety protection against overcurrent and overvoltage during data processing can be achieved, ultimately ensuring the long-term stable operation of the monitoring system and extending its service life.

[0028] Example 2: See also Figure 3 Another embodiment of the present invention provides an insulator leakage current monitoring system based on magnetoresistance effect, which also includes a cloud storage library 18 electrically connected to the main control module 1. The cloud storage library 18 is used to store relevant data information in the cloud to facilitate later inquiries. By setting up the cloud storage library 18, data cloud storage can be realized later, which is convenient for later inquiries and avoids data loss.

[0029] Example 3: See also Figure 4 Another embodiment of the present invention provides an insulator leakage current monitoring system based on magnetoresistance effect, which also includes a fault process updater 8 electrically connected to the main control module 1. The fault process updater 8 is used to update the fault type reference table in the data storage library 9 in real time. By setting the fault process updater 8, the relevant data of the fault type reference table can be updated regularly in the later stage.

[0030] Example 4: See also Figure 5Another embodiment of the present invention provides an insulator leakage current monitoring system based on magnetoresistance effect, which also includes an alarm module 19. The alarm module 19 is electrically connected to the main control module 1 and is used to provide an alarm reminder when an insulator leakage current fault occurs. The above-mentioned structural setting provides an alarm reminder once a leakage fault occurs.

[0031] Example 5: See also Figure 6 An embodiment of the present invention provides an insulator leakage current monitoring system based on magnetoresistance effect, which also includes a wireless communication module 20. The main control module 1 establishes a communication connection with the wireless communication module 20 through the SPI communication interface for data interaction and wireless data reception and transmission control, and communicates with the faulty mobile device through the wireless communication module 20 to send the insulator leakage current monitoring data to the faulty mobile device. By setting up the wireless communication module 20 and realizing a direct communication connection with the faulty mobile device in the later stage, the background maintenance personnel can timely discover the leakage situation, thereby improving the timeliness of the later maintenance.

[0032] Example 6 Another embodiment of the present invention provides a method for monitoring insulator leakage current based on magnetoresistance effect, comprising the following steps: The current primary acquisition unit detects the primary leakage current on the insulator surface and sends the detected primary leakage current signal to the main control module. The data storage library stores preset leakage current thresholds, preset power-up thresholds, and fault type reference data; The main control module receives the primary leakage current signal and performs leakage current judgment. When the preset leakage current threshold is greater than the primary leakage current, the main control module sends a control instruction to the first control switch. When the preset leakage current threshold is less than the primary leakage current and the primary leakage current is greater than zero, the main control module sends a control instruction to the second control switch. The first control switch controls the working state of the first magnetoresistive current detector according to the instruction of the main control module; The second control switch controls the working state of the second magnetoresistive current detector according to the instruction of the main control module; The first magnetoresistive current detector and the second magnetoresistive current detector both detect leakage current signals outside the insulator in real time, and send the detected leakage current signals to the operational amplifier; The operational amplifier amplifies the leakage current signal and sends the amplified signal to the AD conversion module; The AD conversion module converts the amplified signal into digital form and sends the converted data to the main control module; The main control module sends the converted signal to the fault type analysis unit; The fault type analysis unit performs fault analysis on the converted signal, obtains analysis results, and sends the analysis results to the main control module; The main control module calls the maintenance mode according to the analysis results to make online fault maintenance adjustments, and controls the leakage current replenishment analysis module to work when replenishment is needed, controls the fault current converter to work when fault current conversion is needed, and controls the display module to display the fault leakage current; The leakage current replenishment analysis unit performs leakage current replenishment operations according to the control instructions of the main control module; The fault current converter is used to convert the fault current into the fault leakage current; The fault current intuitive display module is used to display the fault leakage current.

[0033] An embodiment of the present invention provides a method for monitoring leakage current of an insulator using the magnetoresistance effect, which can be applied to the leakage current monitoring of insulators using the tunnel magnetoresistance effect. It can monitor insulator faults, perform online analysis and processing, achieve accurate detection of leakage current, and intuitively display the specific size of the leakage current.

[0034] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A magnetoresistance effect insulator leakage current monitoring system, comprising: The main control module, the first magnetoresistive current detector, the second magnetoresistive current detector, the operational amplifier and the AD conversion module are characterized in that they also include: a current initial acquisition unit, a data storage library, a first control switch, a second control switch, a fault type analysis unit, a leakage current compensation analysis module, a fault current converter and a fault current intuitive display module; The current primary acquisition unit is used to detect the primary leakage current on the surface of the insulator and send the detected primary leakage current signal to the main control module; The data storage library is used to store preset leakage current thresholds, preset power-up thresholds and fault type reference data; The main control module receives the primary leakage current signal and performs leakage current judgment. When the preset leakage current threshold is greater than the primary leakage current, the main control module sends a control instruction to the first control switch. When the preset leakage current threshold is less than the primary leakage current and the primary leakage current is greater than zero, the main control module sends a control instruction to the second control switch. The first control switch is used to control the working state of the first magnetoresistive current detector according to the instruction of the main control module; The second control switch is used to control the working state of the second magnetoresistive current detector according to the instruction of the main control module; The first magnetoresistive current detector and the second magnetoresistive current detector are both used to detect leakage current signals outside the insulator in real time, and send the detected leakage current signals to the operational amplifier; The operational amplifier is used to amplify the leakage current signal and send the amplified signal to the AD conversion module; The AD conversion module is used to perform analog-to-digital conversion on the amplified signal and send the converted data to the main control module; The main control module sends the converted signal to the fault type analysis unit; The fault type analysis unit is used to perform fault analysis on the converted signal, obtain analysis results, and send the analysis results to the main control module; The main control module calls the maintenance mode according to the analysis results to perform online fault maintenance adjustment, and controls the leakage current replenishment analysis module to work when replenishment is needed, controls the fault current converter to work when fault current conversion is needed, and controls the fault current intuitive display module to display the fault leakage current; The leakage current replenishment analysis unit performs leakage current replenishment operations according to the control instructions of the main control module; The fault current converter is used to convert the fault current into a fault leakage current; The fault current intuitive display module is used to display the fault leakage current.

2. The system according to claim 1, wherein It also includes a magnetic field detector and a magnetic field shield, and the data storage library also stores a preset magnetic field magnitude threshold. The magnetic field detector is used to detect the magnetic field magnitude of the environment to be tested and send the detected magnetic field signal to the main control module; The main control module performs magnetic field evaluation on the magnetic field signal to determine whether the magnetic field meets the requirements, and sends a shielding control signal to the magnetic field shield when the magnetic field size exceeds a preset magnetic field size threshold; The magnetic field shielding device performs magnetic field shielding according to a shielding control signal.

3. The system according to claim 2, wherein: The main control module performs magnetic field evaluation on the magnetic field signal, specifically including: The magnetic field judgment formula is used to judge the magnetic field. The magnetic field judgment formula is: ； Where H is the magnetic field strength, N is the number of turns of the excitation coil, is the measured excitation current, Le is the effective magnetic path length of the test sample, and Delta is the preset magnetic field strength error setting value which is a constant.

4. The system according to claim 1, wherein: The main control module receives the primary leakage current signal and performs leakage current judgment, which specifically includes: The leakage current evaluation formula is used for judgment, and the leakage current evaluation formula is: ; Where, I is the leakage current detected, U is the voltage applied across the insulator, R is the resistance of the insulator, and I0 is the leakage current error setting value which is a constant.

5. The system according to claim 1, wherein: It also includes a protection module, which is connected to the AD conversion module and the main control module respectively, and is used to perform overcurrent and overvoltage protection on the converted data.

6. The system according to claim 1, wherein: A cloud storage repository is also included, and the cloud storage repository is used for cloud storage of monitoring data.

7. The system according to claim 1, wherein: It also includes a power module, which includes a wind power generation module, a charge and discharge protection module and a battery module, and the charge and discharge protection module is connected to the battery module and the wind power generation module respectively; The wind power generation module is used to convert wind energy into electrical energy; The charge and discharge protection module provides overcurrent, overvoltage and overload protection for the battery during charging; The battery module is used to store the electric energy converted from wind power generation.

8. The system according to claim 1, wherein: It also includes a fault process updater, which is used to update the fault type data in the data storage library in real time.

9. The system according to claim 1, wherein: It also includes an alarm module and a wireless communication module. The alarm module is connected to the main control module and is used to issue an alarm when an insulator leakage current fault occurs. The wireless communication module is used to send the insulator leakage current monitoring data to the fault mobile device.

10. A method for monitoring insulator leakage current based on magnetoresistance effect, characterized in that: include: The current primary acquisition unit detects the primary leakage current on the insulator surface and sends the detected primary leakage current signal to the main control module. The data storage library stores preset leakage current thresholds, preset power-up thresholds, and fault type reference data; The main control module receives the primary leakage current signal and performs leakage current judgment. When the preset leakage current threshold is greater than the primary leakage current, the main control module sends a control instruction to the first control switch. When the preset leakage current threshold is less than the primary leakage current and the primary leakage current is greater than zero, the main control module sends a control instruction to the second control switch. The first control switch controls the working state of the first magnetoresistive current detector according to the instruction of the main control module; The second control switch controls the working state of the second magnetoresistive current detector according to the instruction of the main control module; The first magnetoresistive current detector and the second magnetoresistive current detector both detect leakage current signals outside the insulator in real time, and send the detected leakage current signals to the operational amplifier; The operational amplifier amplifies the leakage current signal and sends the amplified signal to the AD conversion module; The AD conversion module converts the amplified signal into digital form and sends the converted data to the main control module; The main control module sends the converted signal to the fault type analysis unit; The fault type analysis unit performs fault analysis on the converted signal, obtains analysis results, and sends the analysis results to the main control module; The main control module calls the maintenance mode according to the analysis results to make online fault maintenance adjustments, and controls the leakage current replenishment analysis module to work when replenishment is needed, controls the fault current converter to work when fault current conversion is needed, and controls the fault current intuitive display module to display the fault leakage current; The leakage current replenishment analysis module performs leakage current replenishment operations according to the control instructions of the main control module; The fault current converter is used to convert the fault current into the fault leakage current; The fault current intuitive display module is used to display the fault leakage current.

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