GIS equipment partial discharge detection method and device

Abstract

The invention discloses a GIS equipment partial discharge detection method and device. The method comprises the following steps: acquiring an ultrahigh-frequency signal acquired by an ultrahigh-frequency detection module and an ultrasonic signal acquired by an ultrasonic detection module; associating the ultrahigh frequency signal and the ultrasonic signal with each air chamber in the GIS equipment to be detected based on coordinate information of the ultrahigh frequency detection module and the ultrasonic detection module; according to the ultrahigh frequency signal and the ultrasonic signal, determining a target air chamber in which partial discharge occurs in the GIS equipment to be detected; and determining the positioning position of the partial discharge source in the target air chamber according to the ultrahigh frequency signal and the ultrasonic signal associated with the target air chamber. According to the method provided by the invention, the partial discharge source is accurately positioned in the GIS equipment through the ultrahigh frequency signal and the ultrasonic signal, and meanwhile, the anti-interference capability of the detection method is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of power systems, and in particular to a method and device for detecting partial discharge of GIS equipment. Background Art

[0002] Gas Insulated Switchgear (GIS) is a high-voltage power transmission and distribution equipment adapted to the new clean, low-carbon, safe and efficient power system. However, during the production, transportation and installation of GIS equipment, dust, particles and other metal foreign matter will inevitably be generated due to contact and collision. These potential defects will cause partial discharge inside the equipment under strong electric fields. If not handled in time, it may even cause insulation breakdown, seriously threatening the safe operation of the equipment. If the discharge signal can be detected when partial discharge occurs in GIS equipment, the defect location can be determined and handled in time, it can avoid the equipment defect amplification and cause more serious insulation problems.

[0003] However, in the related technologies of partial discharge detection, the positioning accuracy of the partial discharge position is low, and the effect of partial discharge positioning of GIS equipment cannot be guaranteed. Summary of the invention

[0004] In view of this, the present application provides a method and device for detecting partial discharge of GIS equipment, which accurately locates the local discharge source in the GIS equipment through ultra-high frequency signals and ultrasonic signals, while ensuring the anti-interference ability of the detection method.

[0005] According to one aspect of the present application, a method for detecting partial discharge of GIS equipment is provided, comprising: acquiring an ultra-high frequency signal collected by an ultra-high frequency detection module and an ultrasonic signal collected by an ultrasonic detection module; associating the ultra-high frequency signal and the ultrasonic signal with each air chamber in the GIS equipment to be tested based on the coordinate information of the ultra-high frequency detection module and the ultrasonic detection module; determining a target air chamber in which partial discharge occurs in the GIS equipment to be tested according to the ultra-high frequency signal and the ultrasonic signal; determining the location of the partial discharge source in the target air chamber according to the ultra-high frequency signal and the ultrasonic signal associated with the target air chamber.

[0006] According to another aspect of the present application, a GIS equipment partial discharge detection device is provided, which is applied to the above-mentioned GIS equipment partial discharge detection method, including: an ultra-high frequency detection module, an ultrasonic detection module and a signal processing module; the ultra-high frequency detection module is located at a first preset position of the GIS equipment to be tested, and is used to collect the ultra-high frequency signal generated by the local discharge source; wherein the first preset position is the outer shell corresponding to the interval between each air chamber in the GIS equipment to be tested; the ultrasonic detection module is located at the outer shell of the air chamber, and is used to collect the ultrasonic signal generated by the local discharge source; the signal processing module is connected to the ultra-high frequency detection module and the ultrasonic detection module, and the signal processing module is used to receive the ultra-high frequency signal collected by the ultra-high frequency detection module and the ultrasonic signal collected by the ultrasonic detection module, and determine the positioning position of the local discharge source according to the ultra-high frequency signal and the ultrasonic signal.

[0007] By means of the above technical scheme, the present application provides a method and device for detecting partial discharge of GIS equipment, wherein a UHF detection module and an ultrasonic detection module are arranged in the outer shell of the GIS equipment to be tested, which does not affect the internal structure of the GIS equipment and meets the sealing requirements of the GIS equipment. Furthermore, the UHF detection module is arranged at the interval between each air chamber in the GIS equipment to be tested, and the ultrasonic detection module is arranged at each air chamber, so as to timely capture the partial discharge signals (UHF signals and ultrasonic signals) of each area in the GIS equipment to be tested, thereby preliminarily locating the target air chamber where local power generation occurs in the GIS equipment to be tested based on the UHF signal and the ultrasonic signal, thereby narrowing the detection range. Furthermore, the respective advantages of the UHF signal and the ultrasonic signal are combined to improve the anti-interference ability of the partial discharge detection, accurately locate the position of the partial discharge source in the target air chamber, and ensure the effect of the partial discharge detection.

[0008] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0010] Figure 1 A schematic diagram of the process of the partial discharge detection method for GIS equipment provided in an embodiment of the present application is shown;

[0011] Figure 2 A structural block diagram of a partial discharge detection device for GIS equipment provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0012] The present application will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other without conflict.

[0013] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be interpreted as limiting the present application.

[0014] Those skilled in the art will appreciate that, unless expressly stated, the singular forms "a", "an", "said" and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present application refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. It should be understood that when we refer to an element as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, or there may be intermediate elements. In addition, the "connection" or "connection" used herein may include wireless connection or wireless fusion. The term "and / or" used herein includes all or any unit and all combinations of one or more associated listed items.

[0015] Now, exemplary embodiments according to the present application will be described in more detail with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in a variety of different forms and should not be interpreted as being limited to the embodiments set forth herein. It should be understood that these embodiments are provided to make the disclosure of the present application thorough and complete, and to fully convey the concepts of these exemplary embodiments to those of ordinary skill in the art.

[0016] In this embodiment, a GIS equipment partial discharge detection device is provided. Figure 2 As shown, the device includes: a UHF detection module 2, an ultrasonic detection module 3 and a signal processing module 4.

[0017] In this embodiment, a UHF detection module and an ultrasonic detection module are arranged on the shell of the GIS device to be tested, which does not affect the internal structure of the GIS device, meets the sealing requirements of the GIS device, and is easy to move and arrange. Furthermore, the UHF detection module is arranged at the interval between each air chamber in the GIS device to be tested, and the ultrasonic detection module is arranged at each air chamber, so that the large GIS device to be tested is divided into multiple detection areas, and the partial discharge signal of each area is captured in time, thereby realizing the precise positioning of the partial discharge source.

[0018] Specifically, the UHF detection module is located at a first preset position of the GIS device to be tested, and is used to collect the UHF signal generated by the local discharge source; wherein the first preset position is the outer shell corresponding to the interval between each air chamber in the GIS device to be tested.

[0019] For example, Figure 2 As shown, the GIS device 1 to be tested is a real GIS device, with a GIS real pipe 5, a rigid shell, a height of about 2000mm, and four air chambers, with a length of about 3000mm. To facilitate inflation, each air chamber in the pipe 5 is equipped with a self-sealing valve, which can be filled with SF as needed. 6 Gas tank 8 is filled with SF 6 A certain number of metal particles 10 are placed in the gas pipeline 5 to simulate the local discharge defects caused by the metal particles 10 in the GIS equipment in actual working conditions. The UHF detection module 2 is used to detect the UHF signal generated by the local discharge of the GIS equipment 1 to be tested, and an external UHF sensor 13 is used, which is placed on the outer diameter of the insulator of the valve. Furthermore, the UHF detection module 2 includes an external UHF sensor 13, a UHF broadband receiving antenna 14, a UHF connector 15 and a high-pass filter 16. Among them, the UHF broadband receiving antenna 14 is connected to the external UHF sensor 13 to increase the strength of the UHF signal collected by the UHF sensor 13 and reduce signal interference and attenuation. The UHF connector 15 connects the UHF broadband receiving antenna 14 and the high-pass filter 16. The high-pass filter 16 is used to reduce noise interference, improve the smoothness of the UHF signal, and send the UHF signal after filtering out the interference signal to the signal processing module 4.

[0020] For example, the metal particles may be made of aluminum, spherical in shape, with a particle size of 2 mm, and placed near the bottom of the insulator of the valve. Figure 2 As shown, the GIS true pipeline 5 is connected to the DC source 6 via a high-voltage wire 7 , the high-voltage wire 7 is surrounded by an insulating pipe 11 , and the insulating pipe 11 is connected to a grounding device 12 .

[0021] It should be noted that Figure 2 Only one group of UHF detection modules 2 and two groups of ultrasonic detection modules 3 are shown.

[0022] Furthermore, the ultrasonic detection module is located at the outer shell of the air chamber and is used to collect ultrasonic signals generated by the partial discharge source.

[0023] For example, Figure 2 As shown, a set of ultrasonic detection modules 3 is provided for each air chamber of the GIS device 1 to be tested. Since the detection range of the ultrasonic sensor 17 is small, but the positioning is more accurate, multiple ultrasonic sensors 17 are required to cooperate in positioning. In this embodiment, each ultrasonic detection module 3 includes two ultrasonic sensors 17. The two ultrasonic sensors 17 are close to the outer casing of the GIS equipment pipeline 5 to be tested, and are arranged on opposite sides of the air chamber with the adjacent UHF sensor 13 as the center, so that an ultrasonic sensor 17 is placed on the upper left, lower left, upper right, and lower right of each UHF sensor 13. The ultrasonic detection module 3 also includes an ultrasonic pre-gain amplifier 18 and an ultrasonic connecting cable 19. The ultrasonic sensor 17 receives the ultrasonic signal, enhances the ultrasonic signal through the ultrasonic pre-gain amplifier 18, and transmits the enhanced ultrasonic signal to the signal processing module 4 through the ultrasonic connecting cable 19.

[0024] For example, the ultrasonic sensor can use a piezoelectric sensor, which is a high-sensitivity, low-frequency, low-noise differential acoustic emission sensor with good anti-electromagnetic interference capability. The shell is made of stainless steel, and the side in contact with the ground is an insulating material ceramic. The ultrasonic preamplifier can use a low-noise amplifier with a gain multiple of about 35dB.

[0025] Furthermore, the signal processing module is connected to the UHF detection module and the ultrasonic detection module. The signal processing module is used to receive the UHF signal collected by the UHF detection module and the ultrasonic signal collected by the ultrasonic detection module, and determine the location of the local discharge source based on the UHF signal and the ultrasonic signal.

[0026] For example, Figure 2 As shown, the signal processing module 4 is connected to the high-pass filter 16 in the UHF detection module 2 and the ultrasonic connection cable 19 in the ultrasonic detection module 3 through the data acquisition connection cable 20 to receive the UHF signal collected by the UHF detection module 2 and the ultrasonic signal collected by the ultrasonic detection module 3. Among them, the signal processing module 4 includes a data acquisition analyzer 21, a test host 23 and an oscilloscope 22. The data acquisition analyzer 21 is connected to the data acquisition connection cable 20, and the test host 23 and the oscilloscope 22 are respectively connected to the data acquisition analyzer 21.

[0027] In actual application scenarios, such as Figure 2As shown, voltage is applied to the GIS device to be tested through a DC source 6 to ensure that the GIS device to be tested 1 is in an operating voltage state, and air is inflated and pressurized through a pressure pump 9 to simulate actual operating conditions until a partial discharge signal (UHF signal and ultrasonic signal) appears. The oscilloscope 22 observes the partial discharge signal, and at the same time, a specific waveform appears in the oscilloscope 22 and the data acquisition analyzer 21. Since there will be other stray signals on site, the data acquisition analyzer 21 needs to perform noise reduction on the collected signals. The test host 23 determines the location of the partial discharge source based on the UHF signal and ultrasonic signal after noise reduction.

[0028] For example, the data acquisition connection cable can be an ultra-low loss stable amplitude and phase radio frequency cable, the inner conductor is in the form of silver-plated copper, and the shielding is in the form of an inner and outer double shielding layer wrapped with silver-plated copper tape. The data acquisition analyzer can use a multi-channel data acquisition system, the hardware core is a data acquisition card, and the composition structure includes a digital signal processor, a programmable logic device and a memory.

[0029] It should be noted that according to Figure 2 After the partial discharge detection device for GIS equipment is built, before conducting the detection, each detection module needs to be debugged to ensure that each sensor is in a working state that can receive a specific frequency, including the frequency response of the UHF sensor 13 and the sensitivity adjustment of the ultrasonic sensor 17.

[0030] In this embodiment, a method for detecting partial discharge of GIS equipment is provided, which is applied to the device for detecting partial discharge of GIS equipment in the above embodiment. Figure 1 As shown, the method includes:

[0031] Step 101, obtaining a UHF signal collected by a UHF detection module and an ultrasonic signal collected by an ultrasonic detection module.

[0032] Step 102, based on the coordinate information of the UHF detection module and the ultrasonic detection module, the UHF signal and the ultrasonic signal are associated with each air chamber in the GIS device to be tested.

[0033] In this embodiment, a corner of the GIS pipeline to be tested can be used as the origin to establish a three-dimensional spatial coordinate. Next, according to the setting principle and coordinate information of each detection module in the GIS equipment partial discharge detection device of the above embodiment, the air chamber collected by each detection module is determined, so that the signal collected by each detection module is associated with each air chamber in the GIS pipeline to be tested, so that each air chamber is associated with a UHF signal and two ultrasonic signals reflecting its internal discharge situation.

[0034] It should be noted that, since the UHF detection module is arranged at the outer shell of each air chamber, there are two air chambers corresponding to one UHF detection module. Figure 2 As shown, the UHF sensor 13 in the UHF detection module 2 simultaneously collects UHF signals in two adjacent air chambers.

[0035] Step 103, determining the target air chamber where partial discharge occurs in the GIS device to be tested according to the UHF signal and the ultrasonic signal.

[0036] In this embodiment, the UHF signals and ultrasonic signals collected by each detection module are comprehensively analyzed to improve the accuracy and reliability of partial discharge detection, and the target air chamber where local power generation occurs in the GIS equipment to be tested is preliminarily located, thereby narrowing the detection range and improving the detection efficiency.

[0037] Further, as a refinement and expansion of the specific implementation methods of the above-mentioned embodiment, in order to fully illustrate the specific implementation process of this embodiment, step 103, that is, the step of determining the target air chamber where local discharge occurs in the GIS equipment to be tested based on the UHF signal and the ultrasonic signal, specifically includes: sorting the UHF signals according to the maximum signal amplitude of the UHF signals, determining the first signal sequence, and determining the UHF signal that is located before the preset position in the first signal sequence as the candidate signal; determining the distance difference according to the time difference between detecting different candidate signals; and determining the target air chamber based on the coordinate information of the candidate UHF sensor and the distance difference and the preset length of the air chamber.

[0038] The distance difference is the difference in distances between the local discharge source and different candidate UHF sensors, the candidate UHF sensor is the UHF sensor corresponding to the candidate signal, and the UHF sensor is located in the UHF detection module.

[0039] In this embodiment, the propagation characteristics and sensitivities of the UHF signal and the ultrasonic signal are combined to perform positioning, which can fully utilize their advantages and improve the accuracy of positioning.

[0040] Specifically, based on the characteristics that the propagation speed of UHF signals is faster than that of ultrasonic signals, it is easier to determine the peak point, and it can avoid interference from corona, etc., and has good anti-interference ability, the UHF signal will be received first when local discharge occurs. Therefore, based on the UHF signal as a benchmark, the UHF signals collected by the UHF sensors in each UHF detection module are sorted from large to small according to the maximum signal amplitude (peak point) of the UHF signal. Based on the principle that electromagnetic wave signals attenuate with increasing propagation distance, the two UHF signals with the largest maximum signal amplitude are determined as candidate signals, thereby determining the candidate UHF sensors that are closer to the local discharge source among all UHF sensors, and then preliminarily determining the area where local discharge occurs in the GIS equipment to be tested based on the coordinate information of the candidate UHF sensors.

[0041] It should be noted that, based on the principle that electromagnetic wave signals attenuate as the propagation distance increases, the UHF signal amplitude detected by the UHF sensors on both sides of the local discharge source should be the largest, so the candidate UHF sensors are usually two adjacent UHF sensors.

[0042] Furthermore, the difference in the time when the two candidate signals are detected is calculated, and the difference in the distance between the local discharge source and the two candidate UHF sensors is determined based on the product of the time difference and the propagation speed of the UHF signal. If the distance difference is less than the length of a single air chamber, it means that the local discharge source is located in the air chamber between the two candidate UHF sensors, and the air chamber between the two candidate UHF sensors is determined as the target air chamber. Considering the deviation of the actual measurement, if the distance difference is close to (equal to) the length of a single air chamber, based on the principle that the electromagnetic wave signal attenuates with the increase of the propagation distance, it means that the local discharge source is located on the side of the candidate UHF sensor corresponding to the candidate signal with a larger maximum signal amplitude, and this side is far away from the candidate UHF sensor corresponding to the candidate signal with a smaller maximum signal amplitude, so the air chamber on this side is determined as the target air chamber.

[0043] Furthermore, as a refinement and extension of the specific implementation methods of the above-mentioned embodiment, in order to fully illustrate the specific implementation process of this embodiment, step 103, that is, the step of determining the target air chamber where local discharge occurs in the GIS equipment to be tested based on the UHF signal and the ultrasonic signal, also includes: updating the ultrasonic signal associated with the air chamber based on the maximum signal amplitude of the UHF signal associated with the air chamber; superimposing the updated ultrasonic signals associated with the air chamber, and averaging the superimposed ultrasonic signals to determine the average signal of the air chamber; and determining the target air chamber based on the maximum signal amplitude of the average signal.

[0044] In this embodiment, based on the characteristic that the peak point of the UHF signal is easier to determine, the peak point of the UHF signal is used as a reference, the ultrasonic signals associated with each air chamber are aligned and coherent average noise reduction processing is performed, and the maximum signal amplitude comparison method is used to preliminarily determine the location where the local discharge occurs and determine in which air chamber the local discharge occurs.

[0045] Exemplarily, when local discharge occurs, the UHF sensors at the intervals between each air chamber and the two ultrasonic sensors in each air chamber start to collect signals at the same time. For any air chamber, since the propagation speed of the UHF signal is faster than that of the ultrasonic signal, the UHF signal will be received first when local discharge occurs. Therefore, the maximum signal amplitude of the UHF signal associated with the air chamber is determined as the peak point, and the time corresponding to the peak point is used as the time when the local discharge occurs. The ultrasonic signals collected by the two ultrasonic sensors of the air chamber are aligned in time with the peak point as the reference. For example, if the peak point of the UHF signal associated with the air chamber is at time t on the time axis. 0 , then the signals of the two ultrasonic sensors of the air chamber are time-shifted as a whole, so that the starting points of the two ultrasonic signals associated with the air chamber are at the same time as t 0 Overlap ensures that the UHF signal and the ultrasonic signal are comparable in time, providing a unified time reference for subsequent analysis and processing, thereby updating the two ultrasonic signals associated with the air chamber.

[0046] Furthermore, the two aligned ultrasonic signals associated with each air chamber are superimposed. Since the propagation paths and times of the ultrasonic signals generated by partial discharge in the two ultrasonic sensors in the same air chamber are different, but they all originate from the same partial discharge source, they have a certain correlation. By superimposing the two ultrasonic signals, the strength of the partial discharge signal can be enhanced while reducing the impact of random noise.

[0047] The superimposed ultrasonic signals are averaged. Averaging can further reduce the impact of noise, improve the signal-to-noise ratio of the signal, and highlight the characteristics of partial discharge, so that the average signal can be used to represent the ultrasonic signal of the entire air chamber. For example, the value of the superimposed signal at each time point is divided by 2 to obtain the average signal value.

[0048] Based on the principle that electromagnetic wave signals attenuate as the propagation distance increases, the closer the ultrasonic sensor is to the local discharge source, the greater the signal amplitude it receives. Therefore, the air chambers are sorted from large to small according to the maximum amplitude of the average signal, and the air chamber corresponding to the average signal with the largest maximum signal amplitude is determined as the target air chamber.

[0049] It is worth mentioning that, in practical applications, the two methods for determining the target gas chamber in the above embodiments can be performed simultaneously and verified with each other, thereby ensuring the reliability of the target gas chamber and the accuracy of partial discharge detection.

[0050] Step 104 , determining the location of the local discharge source in the target air chamber according to the UHF signal and the ultrasonic signal associated with the target air chamber.

[0051] In this embodiment, the detection area is further narrowed according to the UHF signal and the ultrasonic signal associated with the target gas chamber, and the precise location of the local discharge source is determined.

[0052] Further, as a refinement and expansion of the specific implementation of the above embodiment, in order to fully illustrate the specific implementation process of this embodiment, step 104, i.e., the step of determining the positioning position of the local discharge source in the target air chamber according to the ultra-high frequency signal and the ultrasonic signal associated with the target air chamber, specifically includes: determining the ultra-high frequency signal associated with the target air chamber as the target ultra-high frequency signal; sorting the ultrasonic signals associated with the air chambers adjacent to the target air chamber to determine the second signal sequence, and determining the ultrasonic signal at the first position in the second signal sequence as the auxiliary signal; determining the auxiliary signal and the ultrasonic signal associated with the target air chamber as the positioning signal; determining the ultrasonic sensor corresponding to the positioning signal as the positioning sensor, wherein the ultrasonic sensor is located in the ultrasonic detection module; determining the distance between the local discharge source and the positioning sensor according to the time difference between the target ultra-high frequency signal and the positioning signal; establishing the positioning equation of the local discharge source according to the coordinate information of the positioning sensor and the distance between the local discharge source and the positioning sensor; solving the positioning equation to obtain the positioning position of the local discharge source.

[0053] In this embodiment, the time difference of arrival (TDOA) method is adopted to calculate the distance between the local discharge source and the sensor by using the time difference of the local discharge signal arriving at sensors at different positions, and the local discharge source positioning equation is established by using the calculated distance, so as to accurately locate the position of the local discharge source by solving the positioning equation.

[0054] Exemplarily, the UHF signal associated with the target air chamber is determined as the target UHF signal. At the same time, the ultrasonic signals associated with the air chambers adjacent to the target air chamber are sorted from large to small according to the maximum signal amplitude, the second signal sequence is determined, and the ultrasonic signal at the first position in the second signal sequence is determined as the auxiliary signal, so that the ultrasonic sensor closest to the local discharge source is determined according to the ultrasonic sensor corresponding to the auxiliary signal, excluding the ultrasonic sensor associated with the target air chamber. Then, the ultrasonic signal associated with the target air chamber and the auxiliary signal are both determined as positioning signals, and the ultrasonic sensor corresponding to the positioning signal is determined as the positioning sensor, and then the local discharge source is located according to the positioning signals collected by the three positioning sensors closest to the local discharge source to ensure the accuracy of positioning.

[0055] Furthermore, based on the fast propagation speed of UHF signals, the time t at which the target UHF signal is detected is 0 The time when partial discharge occurs is determined. Assume that the coordinates of the partial discharge source are P (x, y, z), the number of positioning sensors n is 3, and the coordinates of the i-th positioning sensor are S i (x i ,y i , z i ), i = 1, 2, .., n. The propagation speed of the ultrasonic signal in the medium is v, and the time when the positioning signal of the i-th positioning sensor is detected is t i According to the relationship between time, speed and distance, the distance d between the local discharge source and the i-th positioning sensor is i =v(t i -t 0 ). According to the spatial distance formula, the local discharge source positioning equation can be obtained:

[0056]

[0057] Therefore, by solving the local discharge source positioning equation, the precise positioning position of the local discharge source can be obtained.

[0058] In one embodiment, the local discharge detection method for GIS equipment also includes: establishing a three-dimensional model of the GIS equipment to be tested based on basic data of the GIS equipment to be tested; determining the propagation path error and measurement error of the positioning signal based on simulation data of the target air chamber in the three-dimensional model and simulation data of the air chamber associated with the auxiliary signal in the three-dimensional model; and updating the distance between the local discharge source and the positioning sensor based on the propagation path error and the measurement error.

[0059] In this embodiment, considering the complex structure inside the GIS equipment, there may be large errors in calculating the distance only by relying on the simple signal propagation time difference. This embodiment can more accurately calculate the distance between the local discharge source and the positioning sensor by establishing a three-dimensional model to quantify the propagation path error and measurement error. This helps to improve the accuracy of the local discharge source positioning and avoid inaccurate positioning due to large errors.

[0060] Exemplarily, an accurate three-dimensional model of the GIS device to be tested is established based on the basic data of the GIS device to be tested, such as the size, shape, positional relationship of each component of the device, etc. The established three-dimensional model is used to simulate the propagation of ultrasonic signals in the target air chamber and the air chamber associated with the auxiliary signal. By comparing the actual detected positioning signal with the propagation simulated in the model, the propagation path error can be determined. For example, the actual signal may be different from the ideal straight-line propagation path due to the complexity of the internal structure of the device, reflection, refraction and other factors. At the same time, the measurement error is considered, which may come from the accuracy of the sensor, the error in the signal processing process, etc. The propagation path error and the measurement error are comprehensively considered, and the distance between the local discharge source and the positioning sensor determined in the above embodiment is updated to obtain a more accurate distance value.

[0061] Further, as a refinement and expansion of the specific implementation of the above embodiment, in order to fully illustrate the specific implementation process of this embodiment, the steps of solving the positioning equation and obtaining the positioning position of the local discharge source specifically include: obtaining a positioning index and a decreasing coefficient of the positioning index; randomly generating coordinate information of the local discharge source; determining a fitness function according to the coordinate information and the positioning equation; perturbing the coordinate information; calculating the fitness difference between the coordinate information after the disturbance and the coordinate information according to the fitness function; updating the coordinate information according to the coordinate information after the disturbance and the fitness difference; reducing the positioning index according to the decreasing coefficient, and perturbing the updated coordinate information until the positioning index is less than a preset index; and determining the positioning position of the local discharge source in the target gas chamber according to the coordinate information corresponding to the positioning index less than the preset index.

[0062] In this embodiment, the positioning equation is solved by a simulated annealing algorithm to avoid falling into a local optimal solution. By accepting poor solutions during the search process, the possibility of finding a global optimal solution is increased, thereby accurately locating the location where local discharge occurs in the GIS device to be tested.

[0063] For example, an initial coordinate information (x 0 ,y 0 , z 0 ), as the initial location estimate of the local discharge source. Set the initial location index T 0 and the decrease coefficient α of the positioning index.

[0064] For the current coordinate information of the partial discharge source (x s ,y s , z s ), calculate the fitness function:

[0065]

[0066] The fitness function represents the sum of squares of the errors between the current coordinate information and the actual distance. The actual distance is the distance d between the local discharge source and the positioning sensor determined based on the time difference between the positioning signal and the target UHF signal. i .

[0067] Next, in the current coordinate information (x s ,y s , z s ) is randomly disturbed based on the coordinate information (x', y', z') after the disturbance is generated. Exemplarily, a small random number can be added to the coordinate component of the current coordinate information, such as x'=x+ε, where ε is a random number that obeys a specific distribution, so that the amplitude of the disturbance is moderate, neither too small to limit the search space, nor too large to make the solution process too random.

[0068] Furthermore, the fitness f(x', y', z') of the disturbed coordinate information (x', y', z') is calculated, so as to obtain the coordinate information (x', y', z') after disturbance and the current coordinate information (x s ,y s , z s )’s fitness difference Δf=f(x’,y’,z’)-f(x s ,y s , z s ). Then, according to the fitness difference Δf, it is determined how to update the current coordinate information (x', y', z') according to the disturbed coordinate information (x', y', z'). s ,y s , z s ).

[0069] Furthermore, after the current coordinate information is updated, the current positioning index T is reduced according to the reduction formula T=T*α.

[0070] Then, the updated current coordinate information is disturbed and the next loop iteration is entered until the positioning index T drops to the preset stop index T stop , or, the number of loop iterations reaches a preset number, or, in several consecutive loop iterations, the coordinate information has no obvious change or the change is very small, a threshold can be defined. When the change of the coordinate information in several consecutive iterations is less than this threshold, it is considered that the optimal solution is obtained and the loop iteration is stopped.

[0071] Thus, the location of the local discharge source in the target gas chamber is determined according to the coordinate information that meets the conditions for stopping the cycle iteration.

[0072] It should be noted that in the first iteration, the current coordinate information of the local discharge source (x s ,ys , z s ) is the initial coordinate information (x 0 ,y 0 , z 0 ), the current positioning index T is the initial positioning index T 0 .

[0073] It is worth mentioning that the initial positioning indicator T 0 It should be high enough to accept poor solutions with a higher probability at the beginning, thereby increasing the diversity of the search. The descent coefficient α can be set between 0.9 and 1 to control the speed at which the positioning index decreases. If the positioning index decreases too quickly, it may fall into a local optimal solution; if the positioning index decreases too slowly, the solution time will increase.

[0074] Furthermore, as a refinement and expansion of the specific implementation methods of the above-mentioned embodiment, in order to fully illustrate the specific implementation process of this embodiment, the step of updating the coordinate information according to the disturbed coordinate information and the fitness difference specifically includes: if the fitness difference is less than a preset threshold, updating the coordinate information according to the disturbed coordinate information; if the fitness difference is greater than or equal to the preset threshold, determining the update probability according to the fitness difference greater than or equal to the preset threshold and the positioning index, and updating the disturbed coordinate information to the coordinate information according to the update probability.

[0075] Specifically, if the fitness difference Δf<0 (preset threshold), that is, the coordinate information after disturbance has better fitness, the coordinate information after disturbance is accepted as the current coordinate information. If the fitness difference Δf≥0, then the probability Receive the disturbed coordinate information.

[0076] It is worth mentioning that the probability This reflects the randomness and convergence of the solution process in this embodiment. As the positioning index T decreases, the probability of accepting poor coordinate information will also decrease. This embodiment gradually converges to a better coordinate information.

[0077] The local discharge detection method and device for GIS equipment described in the present application can avoid interference from corona and the like by combining with the ultra-high frequency detection method, and has good anti-interference ability. It can also realize complementary advantages by performing local discharge detection on GIS equipment by combining the high positioning accuracy of the ultrasonic detection method, and can not only capture local discharge signals in a timely manner and accurately locate the local discharge source, but also ensure the anti-interference ability of the detection method.

[0078] Those skilled in the art will appreciate that the accompanying drawings are only schematic diagrams of a preferred implementation scenario, and the modules or processes in the accompanying drawings are not necessarily necessary for implementing the present application. Those skilled in the art will appreciate that the modules in the devices in the implementation scenario can be distributed in the devices of the implementation scenario according to the description of the implementation scenario, or can be changed accordingly and located in one or more devices different from the present implementation scenario. The modules of the above-mentioned implementation scenario can be combined into one module, or can be further split into multiple submodules.

[0079] The above serial numbers of this application are only for description and do not represent the advantages and disadvantages of the implementation scenarios. The above disclosure is only a few specific implementation scenarios of this application, but this application is not limited to them, and any changes that can be thought of by technicians in this field should fall within the scope of protection of this application.

Claims

1. A method for detecting partial discharge of GIS equipment, characterized in that: The method comprises: Acquire the ultra-high frequency signal collected by the ultra-high frequency detection module and the ultrasonic signal collected by the ultrasonic detection module; Based on the coordinate information of the UHF detection module and the ultrasonic detection module, the UHF signal and the ultrasonic signal are associated with each air chamber in the GIS device to be tested; Determine the target air chamber where partial discharge occurs in the GIS device to be tested according to the UHF signal and the ultrasonic signal; The location of the local discharge source in the target air chamber is determined according to the ultra-high frequency signal and the ultrasonic signal associated with the target air chamber.

2. The GIS equipment partial discharge detection method according to claim 1, characterized in that: The step of determining a target air chamber where partial discharge occurs in the GIS device to be tested according to the UHF signal and the ultrasonic signal comprises: sorting the UHF signals according to the maximum signal amplitude of the UHF signals to determine a first signal sequence, and determining the UHF signals located before a preset position sequence in the first signal sequence as candidate signals; Determine a distance difference according to a time difference between detecting different candidate signals, wherein the distance difference is a difference in distances between the local discharge source and different candidate UHF sensors, the candidate UHF sensor is a UHF sensor corresponding to the candidate signal, and the UHF sensor is located in the UHF detection module; Based on the coordinate information of the candidate UHF sensor, the target air chamber is determined according to the distance difference and a preset length of the air chamber.

3. The GIS equipment partial discharge detection method according to claim 1, characterized in that: The step of determining the target air chamber where partial discharge occurs in the GIS device to be tested according to the UHF signal and the ultrasonic signal further includes: updating the ultrasonic signal associated with the air chamber according to the maximum signal amplitude of the ultra-high frequency signal associated with the air chamber; superimposing the updated ultrasonic signals associated with the air chamber, and averaging the superimposed ultrasonic signals to determine an average signal of the air chamber; The target gas chamber is determined according to the maximum signal amplitude of the average signal.

4. The GIS equipment partial discharge detection method according to claim 1, characterized in that: The method of determining the location of the local discharge source in the target air chamber according to the ultra-high frequency signal and the ultrasonic signal associated with the target air chamber comprises: Determine the UHF signal associated with the target air chamber as the target UHF signal; Sorting the ultrasonic signals associated with the air chambers adjacent to the target air chamber to determine a second signal sequence, and determining the ultrasonic signal at the first position in the second signal sequence as an auxiliary signal; determining an ultrasonic signal associated with the auxiliary signal and the target air chamber as a positioning signal; Determine the ultrasonic sensor corresponding to the positioning signal as the positioning sensor, wherein the ultrasonic sensor is located in the ultrasonic detection module; determining the distance between the local discharge source and the positioning sensor according to the time difference between the detection of the target UHF signal and the positioning signal; Establishing a positioning equation of the local discharge source according to the coordinate information of the positioning sensor and the distance between the local discharge source and the positioning sensor; The positioning equation is solved to obtain the positioning position of the local discharge source.

5. The GIS equipment partial discharge detection method according to claim 4, characterized in that: The method further comprises: Establishing a three-dimensional model of the GIS device to be tested according to the basic data of the GIS device to be tested; Determine a propagation path error and a measurement error of the positioning signal according to simulation data of the target air chamber in the three-dimensional model and simulation data of an air chamber associated with the auxiliary signal in the three-dimensional model; The distance between the partial discharge source and the positioning sensor is updated according to the propagation path error and the measurement error.

6. The GIS equipment partial discharge detection method according to claim 4, characterized in that: The step of solving the positioning equation to obtain the positioning position of the local discharge source includes: Obtaining a positioning indicator and a reduction coefficient of the positioning indicator; randomly generating coordinate information of the partial discharge source; Determine a fitness function according to the coordinate information and the positioning equation; perturbing the coordinate information; Calculate the fitness difference between the coordinate information after disturbance and the coordinate information according to the fitness function; updating the coordinate information according to the coordinate information after disturbance and the fitness difference; reducing the positioning index according to the reduction coefficient, and disturbing the updated coordinate information until the positioning index is less than a preset index; The location of the local discharge source in the target gas chamber is determined according to the coordinate information corresponding to the positioning index that is smaller than the preset index.

7. The method for detecting partial discharge of GIS equipment according to claim 6, characterized in that: Updating the coordinate information according to the disturbed coordinate information and the fitness difference, including: If the fitness difference is less than a preset threshold, updating the coordinate information according to the disturbed coordinate information; If the fitness difference is greater than or equal to the preset threshold, an update probability is determined based on the fitness difference greater than or equal to the preset threshold and the positioning index, and the disturbed coordinate information is updated to the coordinate information based on the update probability.

8. A GIS equipment partial discharge detection device, applied to the GIS equipment partial discharge detection method according to any one of claims 1 to 7, characterized in that: The device comprises: a UHF detection module, an ultrasonic detection module and a signal processing module; The UHF detection module is located at a first preset position of the GIS device to be tested, and is used to collect the UHF signal generated by the partial discharge source; wherein the first preset position is the outer shell corresponding to the interval between each air chamber in the GIS device to be tested; The ultrasonic detection module is located at the outer shell of the air chamber and is used to collect the ultrasonic signal generated by the partial discharge source; The signal processing module is connected to the UHF detection module and the ultrasonic detection module. The signal processing module is used to receive the UHF signal collected by the UHF detection module and the ultrasonic signal collected by the ultrasonic detection module, and determine the location of the local discharge source according to the UHF signal and the ultrasonic signal.

9. The GIS equipment partial discharge detection device according to claim 8, characterized in that: The UHF detection module includes: a UHF sensor and a high-pass filter.

10. The GIS equipment partial discharge detection device according to claim 8, characterized in that: The ultrasonic detection module includes: an ultrasonic sensor and an ultrasonic pre-gain amplifier.

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