Power distribution network insulator and lightning arrester breakdown fault simulation device and processing method

Abstract

The invention discloses a power distribution network insulator and lightning arrester breakdown fault simulation device and processing method, which can realize real simulation of insulator and lightning arrester breakdown faults under a power distribution network reality test platform, restore real fault features on site, and obtain a large amount of effective fault recording data in a short time. Sample collection and fault identification technology research of breakdown faults of insulators and lightning arresters are promoted. The method can be used for testing a fault arc-extinguishing line selection device, a relay protection device and the like on a power distribution network reality test platform. The position of the flexible cable clamp on an overhead line can be changed, so that the fault occurrence point can be controlled, and faults at the head end, the middle end and the tail end of the line can be simulated respectively. The fault insulator or the fault lightning arrester sample is obtained by processing intact elements, has the advantages of being simple, convenient, repeatable and the like, can simulate relatively consistent fault features, and avoids the influence of the difference of fault simulation effects on the test result.

Description

Technical Field

[0001] The invention relates to the technical field of distribution network insulator and lightning arrester breakdown fault simulation, and in particular to a distribution network insulator and lightning arrester breakdown fault simulation device and a processing method. Background Art

[0002] Single-phase grounding fault is the most common fault type in 10kV distribution network. When a single-phase grounding fault occurs, the system is allowed to continue to operate with the fault for 1 to 2 hours. As the scale of distribution network and the cable rate gradually increase, the single-phase grounding fault current gradually increases, and the grounding arc is difficult to eliminate. If the fault is not eliminated or isolated in time, it will cause serious overvoltage in the power grid, causing damage to electrical equipment, affecting power supply reliability, and bringing high safety hazards. Insulator flashover and lightning arrester breakdown are two important reasons for the occurrence of single-phase grounding faults in distribution networks. Traditional digital simulation or dynamic model testing is difficult to restore the real fault characteristics on site, difficult to collect effective fault recording signals, and unable to accurately test the real performance of new technologies or new products.

[0003] The distribution network reality test platform is a 10kV distribution network real test field based on real distribution network equipment. It can simulate the operating environment on the real line and provide test conditions. The current resistance-type single-phase grounding fault simulation device simulates different resistance grounding by adjusting the grounding transition resistance. It can only simulate linear faults without arcs, and the simulation ability is limited. It is impossible to simulate fault causes such as insulator flashover and lightning arrester breakdown. In view of the above problems, it is necessary to propose an insulator and lightning arrester breakdown fault simulation device and method that can be applied to the distribution network reality test platform. Summary of the invention

[0004] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0005] In view of the above existing problems, the present invention is proposed.

[0006] Therefore, the present invention provides a distribution network insulator and lightning arrester breakdown fault simulation device and processing method, which can solve the problems mentioned in the background technology.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0008] In a first aspect, the present invention provides a device for simulating breakdown faults of insulators and lightning arresters in a distribution network, comprising: a measurement and control unit and a breakdown simulation unit;

[0009] The measurement and control unit includes an isolating switch, a current transformer, a voltage transformer, a control and recording device, and a circuit breaker;

[0010] The breakdown simulation unit includes a wall bushing, a test box, a high-speed camera, a grounding cross arm, a workstation 1 and a workstation 2;

[0011] One end of the measurement and control unit is connected to the 10kV overhead line through an isolating switch, and the other end is connected to the breakdown simulation unit through circuit breaker B1.

[0012] As a preferred solution of the device for simulating breakdown faults of insulators and lightning arresters in a distribution network according to the present invention, the measurement and control unit further comprises:

[0013] The disconnector has three contacts D1, D2 and D3, which respectively control the connection between the A phase, B phase and C phase of the 10kV overhead line and the measurement and control unit;

[0014] The isolating switch has a locking structure, and at most one contact can be closed to prevent two or three phases from being short-circuited to ground at the same time;

[0015] The upper end of the disconnector is connected to a flexible cable, which is electrically connected to the 10kV overhead line through a wire clamp;

[0016] When the position of the wire clamp on the overhead line is changed, the location of the simulated fault will change, and the fault can be simulated to occur at the beginning, middle or end of the line;

[0017] The current transformer collects the zero-sequence current and the fault phase and non-fault phase current signals of the line;

[0018] The voltage transformer collects the zero-sequence voltage of the line and the voltage signals of the fault phase and the non-fault phase;

[0019] The control and recording equipment records the voltage and current signals collected by the transformer, and controls the opening and closing of circuit breaker B1 accordingly, and controls the phase and duration of the simulated fault according to the test requirements.

[0020] As a preferred solution of the device for simulating breakdown faults of insulators and lightning arresters in a distribution network according to the present invention, the breakdown simulation unit further comprises:

[0021] The outgoing line of circuit breaker B1 is introduced into the test box through the wall bushing and connected to workstations 1 and 2 in the form of overhead bare wires;

[0022] The test box is a grounded metal box that protects the test items in the box from interference from external environmental factors during the test;

[0023] A high-speed camera is installed on the inner wall of the test chamber to record the phenomenon at the fault point at the time of the fault and store it synchronously with the recorded data of the fault;

[0024] There are two grounding cross arms, front and rear, with reserved installation positions for insulators and lightning arresters, and effective grounding;

[0025] Workstations 1 and 2 install insulators or lightning arresters on the grounding crossarm according to the test requirements. When simulating an insulator breakdown failure, workstation 1 installs the pre-treated faulty insulator specimen, and workstation 2 installs the intact insulator. When simulating a lightning arrester breakdown failure, workstation 1 installs the intact insulator, and workstation 2 installs the pre-treated faulty lightning arrester specimen.

[0026] As a preferred solution of the distribution network insulator and lightning arrester breakdown fault simulation device of the present invention, wherein: the pre-treated faulty insulator sample comprises:

[0027] Use fuses to connect the metal parts at the beginning and end of the insulator;

[0028] If there is no head end metal part, connect the fuse to the groove of the topmost shed skirt;

[0029] The connection method between the fuse and the first and second ends of the insulator can be winding or single-point connection. The single-point connection is to use an insulating tape or rope to tie and fix the fuse. In the insulator pretreatment, the plane where the fuse is located is at a 45° angle to the conductor.

[0030] As a preferred solution of the distribution network insulator and lightning arrester breakdown fault simulation device of the present invention, wherein: the pre-treated fault lightning arrester test sample comprises:

[0031] The arrester is an AC gapless metal oxide arrester, which uses a fuse to run along and closely adhere to the surface of the resistor to conduct short-circuit current and short-circuit all functional components inside the arrester;

[0032] A protective device is installed in the test chamber to prevent the failure of the arrester jacket from exploding and damaging the equipment in the test chamber.

[0033] As a preferred solution of the distribution network insulator and lightning arrester breakdown fault simulation device of the present invention, it also includes:

[0034] The pretreated faulty insulator sample can also be prepared by preparing a sodium chloride diatomaceous earth contamination liquid of a target concentration, brushing the contamination liquid evenly or spraying it with a spray gun onto the surface of the insulator, and keeping the contamination layer moist, to obtain a pretreated faulty insulator;

[0035] The pre-treated fault arrester sample can also apply a standard lightning pulse current to the arrester resistor through an impulse current generator until it is completely aged and fails, and then the aged resistor is assembled to obtain the pre-treated fault arrester sample.

[0036] In a second aspect, the present invention provides a method for simulating and processing breakdown faults of insulators and lightning arresters in a distribution network, comprising:

[0037] When conducting an insulator breakdown fault simulation test, the processing steps include:

[0038] Step 1: According to the test requirements, prepare the required faulty insulator specimen according to the faulty insulator pretreatment method, install the faulty insulator specimen on the simulation device station 1, install the intact insulator on the station 2, and connect the bare wire led out of the wall bushing to the specimens at the two stations;

[0039] Step 2: Complete the grounding operation of the simulation device, including the entire casing of the simulation device, the grounding crossarm, and other measurement and control equipment that need to be grounded;

[0040] Step 3: Connect the simulation device to the set position of the 10kV overhead line through a flexible cable and a wire clamp. Before the connection, the disconnectors D1, D2, D3 and the circuit breaker B1 are in the open state, and the opening time of the circuit breaker B1 is set according to the test requirements;

[0041] Step 4: According to the selected fault phase, close the corresponding isolating switch;

[0042] Step 5: remotely close the circuit breaker B1, turn on the breakdown simulation unit, and an insulator breakdown fault occurs at station 1;

[0043] Step 6: Circuit breaker B1 automatically opens after the set fault time, disconnects the fault phase isolation switch, and prepares for the next round of tests according to the test requirements.

[0044] As a preferred solution of the method for simulating the breakdown fault of insulators and lightning arresters in the distribution network of the present invention, when performing a simulation test of the breakdown fault of the lightning arrester, the processing steps include:

[0045] Step 1: According to the test requirements, prepare the required fault arrester sample according to the fault arrester pretreatment method, install the intact insulator on the simulation device station 1, install the fault arrester sample on the station 2, and connect the bare wire led out from the wall bushing to the samples at the two stations;

[0046] Step 2: Complete the grounding operation of the simulation device, including the entire casing of the simulation device, the grounding crossarm, and other measurement and control equipment that need to be grounded;

[0047] Step 3: Connect the simulation device to the set position of the 10kV overhead line through a flexible cable and a wire clamp. Before the connection, the disconnectors D1, D2, D3 and the circuit breaker B1 are in the open state, and the opening time of the circuit breaker B1 is set according to the test requirements;

[0048] Step 4: According to the selected fault phase, close the corresponding isolating switch;

[0049] Step 5: Close the circuit breaker B1 remotely, turn on the breakdown simulation unit, and a lightning arrester breakdown failure occurs at station 2;

[0050] Step 6: Circuit breaker B1 automatically opens after the set fault time, disconnects the fault phase isolation switch, and prepares for the next round of tests according to the test requirements.

[0051] In a third aspect, the present invention provides a computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above-mentioned method when executing the computer program.

[0052] In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program implements the steps of the method described above when executed by a processor.

[0053] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention proposes a simulation device and processing method for the breakdown fault of insulators and lightning arresters in a distribution network, which can realize the true simulation of the breakdown fault of insulators and lightning arresters under the actual test platform of the distribution network, restore the real fault characteristics on site, and obtain a large amount of effective fault recording data in a short time, so as to promote the sample collection and fault identification technology research of the breakdown fault of insulators and lightning arresters. The simulation device and method provided by the present invention can be used for testing devices such as fault arc extinguishing line selection devices and relay protection on the actual test platform of the distribution network. The simulation device provided by the present invention can realize the controllable fault occurrence point by changing the position of the flexible cable clamp on the overhead line, and can simulate the faults at the beginning, middle and end of the line respectively. The fault insulator or fault lightning arrester sample used in the present invention is obtained by processing intact components, and has the advantages of simplicity and repeatability, and can simulate relatively consistent fault characteristics, avoiding the influence of differences in fault simulation effects on the test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0055] Figure 1 A schematic diagram of a device for simulating breakdown faults of insulators and lightning arresters in a distribution network and a method for handling breakdown faults of insulators and lightning arresters provided in one embodiment of the present invention;

[0056] Figure 2A schematic diagram of an insulator breakdown fault simulation unit of a distribution network insulator and lightning arrester breakdown fault simulation device and processing method provided by an embodiment of the present invention;

[0057] Figure 3 A schematic diagram of a lightning arrester breakdown fault simulation unit of a distribution network insulator and lightning arrester breakdown fault simulation device and processing method provided by an embodiment of the present invention;

[0058] Figure 4 A schematic diagram of a fault insulator sample pre-processing method of a distribution network insulator and lightning arrester breakdown fault simulation device and processing method provided by an embodiment of the present invention;

[0059] Figure 5 A schematic diagram of a fault arrester sample pretreatment method of a distribution network insulator and arrester breakdown fault simulation device and treatment method provided by an embodiment of the present invention;

[0060] Figure 6 An internal structural diagram of a computer device for simulating and processing breakdown faults of insulators and lightning arresters in a distribution network provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0061] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0062] Example 1

[0063] Reference Figure 1-Figure 6 , which is the first embodiment of the present invention, provides a distribution network insulator and lightning arrester breakdown fault simulation device and processing method, including:

[0064] Before describing the embodiments of the present application in detail, some related concepts are first explained for the sake of clarity.

[0065] Insulator flashover: refers to the abnormal discharge phenomenon that occurs on the surface of the insulator in the power system when it is subjected to voltage. This discharge may be caused by the contamination of the insulator surface. For example, dust, salt spray and other pollutants form a conductive path in a humid environment, causing electricity to be conducted on the surface of the insulator instead of in the internal insulating medium, thus causing the discharge phenomenon. Flashover will lead to instability of the power system and may even cause power outages.

[0066] Lightning arrester breakdown: Lightning arresters are devices designed to protect power systems from lightning strikes or operational overvoltage damage. When a lightning arrester is subjected to a voltage that exceeds its tolerance, the internal protective components (such as resistors) may be permanently damaged. This phenomenon is called breakdown. After breakdown, the lightning arrester may not work properly and lose its protective function. Sometimes, an arc may be generated, which may cause the equipment to explode in severe cases.

[0067] Arrester resistor: This is the main protective element inside the arrester, usually made of metal oxides (such as zinc oxide). These resistors have nonlinear volt-ampere characteristics, that is, they are in a high-resistance state under normal operating voltage, preventing current from flowing; and in overvoltage conditions (such as lightning strikes), they quickly change to a low-resistance state, allowing current to be released without damaging other equipment. The purpose of the design of the resistor is to protect the power system while ensuring its own safe and reliable operation.

[0068] There are some technical problems in the related technologies. For example, in the simulation of breakdown faults of insulators and lightning arresters in distribution networks, traditional simulation methods often cannot accurately reproduce the complexity and diversity of actual faults, resulting in deviations between test results and actual applications. In addition, existing simulation devices lack flexibility in the setting of fault points, making it difficult to simulate fault conditions at different locations of the line.

[0069] The present application provides a method for effectively solving the above-mentioned problems. Next, multiple embodiments will be combined to explain in detail how to establish the device.

[0070] Figure 1 A schematic diagram of a simulation device for breakdown faults of insulators and lightning arresters in a power distribution network and a processing method thereof is shown, comprising: a measurement and control unit and a breakdown simulation unit;

[0071] In the embodiment of the present application, the measurement and control unit includes an isolating switch, a current transformer, a voltage transformer, a control and recording device, and a circuit breaker; the breakdown simulation unit includes a wall bushing, a test box, a high-speed camera, a grounding crossarm, a workstation one, and a workstation two;

[0072] In the embodiment of the present application, one end of the measurement and control unit is connected to the 10kV overhead line through the isolating switch, and the other end is connected to the breakdown simulation unit through the circuit breaker B1.

[0073] In the embodiment of the present application, the measurement and control unit further includes:

[0074] The disconnector has three contacts D1, D2 and D3, which respectively control the connection between the A phase, B phase and C phase of the 10kV overhead line and the measurement and control unit;

[0075] The isolating switch has a locking structure, and at most one contact can be closed to prevent two or three phases from being short-circuited to ground at the same time;

[0076] The upper end of the disconnector is connected to a flexible cable, which is electrically connected to the 10kV overhead line through a wire clamp;

[0077] When the position of the wire clamp on the overhead line is changed, the location of the simulated fault will change, and the fault can be simulated to occur at the beginning, middle or end of the line;

[0078] The current transformer collects the zero-sequence current and the fault phase and non-fault phase current signals of the line;

[0079] The voltage transformer collects the zero-sequence voltage of the line and the voltage signals of the fault phase and the non-fault phase;

[0080] The control and recording equipment records the voltage and current signals collected by the transformer, and controls the opening and closing of circuit breaker B1 accordingly, and controls the phase and duration of the simulated fault according to the test requirements.

[0081] In an optional embodiment, it is determined according to the test requirements whether the fault to be simulated is at the head end, middle end or end of the line. The flexible cable can be fixed at different positions on the 10kV overhead line using a wire clamp. If the fault at the head end position needs to be simulated, the flexible cable is fixed at a position close to the power supply side; if the fault at the middle end position needs to be simulated, the flexible cable is fixed at a position in the middle of the line; if the fault at the end position needs to be simulated, the flexible cable is fixed at a position far away from the power supply side. For example, assuming that the total length of a certain section of 10kV overhead line is 10 kilometers, the distance of each part can be defined as follows: the head end position of the line can refer to a position within a range of about 1 to 2 kilometers from the substation, which can be considered as a part close to the power supply side. The middle end position of the line can refer to a position from the midpoint of the line, that is, about 5 kilometers. The end position of the line can refer to a position close to the end of the line, about 8 to 10 kilometers, which can be considered as a place far away from the power supply side. At this time, if the fault at the head end position is to be simulated, the flexible cable can be fixed by a wire clamp at about 1 kilometer away from the outlet of the substation. If a fault at a mid-end location is to be simulated, the flexible cable may be fixed at about 5 km, and if a fault at an end location is to be simulated, the flexible cable may be fixed at about 9 km.

[0082] For example, in this application Figure 1 It is a device for simulating breakdown faults of insulators and lightning arresters. The simulation device includes a measurement and control unit and a breakdown simulation unit. One end of the measurement and control unit is connected to the 10kV overhead line through a disconnector, and the other end is connected to the breakdown simulation unit through a circuit breaker B1.

[0083] The measurement and control unit includes disconnectors, current transformers, voltage transformers, control and recording equipment, and circuit breaker B1. The disconnectors are used to select the fault phase and connect it to the fault simulation device. Disconnectors D1, D2, and D3 correspond to the three phases A, B, and C of the 10kV overhead line respectively. The disconnectors have a locking structure, and no more than two disconnectors can be in the closed state at the same time. The disconnectors are terminated with flexible cables and fixed to the three phases of the 10kV overhead line through wire clamps. By changing the hanging position of the flexible cable on the overhead line, it can simulate the fault occurring at the beginning, middle, or end of the line; the current transformer collects zero-sequence current signals and current signals of the fault phase and non-fault phase; the voltage transformer collects zero-sequence voltage signals and voltage signals of the fault phase and non-fault phase; the control and recording equipment records and summarizes the electrical signals collected in the transformer, and outputs control signals to the circuit breaker B1, controlling it to close at the appropriate phase and time, and automatically open after the set time.

[0084] It should be noted that in addition to 10kV overhead lines, the present application can also be used in power systems of other voltage levels, such as 35kV, 110kV, 220kV, etc., by simply adjusting the parameters and configurations of the measurement and control unit and the breakdown simulation unit accordingly.

[0085] It should be noted that the design of the measurement and control unit can flexibly simulate fault conditions at different locations, thereby improving the accuracy and practicality of the simulation. By changing the position of the wire clamp on the overhead line, the fault conditions at the beginning, middle or end of the line can be simulated, which makes the test results closer to the fault conditions in actual applications. In addition, the locking structure of the disconnector ensures that there will be no short circuit and grounding of two or three phases at the same time during operation, thereby improving the safety of the test.

[0086] In the embodiment of the present application, the breakdown simulation unit further includes:

[0087] The outgoing line of circuit breaker B1 is introduced into the test box through the wall bushing and connected to workstations 1 and 2 in the form of overhead bare wires;

[0088] The test box is a grounded metal box that protects the test items in the box from interference from external environmental factors during the test;

[0089] A high-speed camera is installed on the inner wall of the test chamber to record the phenomenon at the fault point at the time of the fault and store it synchronously with the recorded data of the fault;

[0090] There are two grounding cross arms, front and rear, with reserved installation positions for insulators and lightning arresters, and effective grounding;

[0091] Workstations 1 and 2 install insulators or lightning arresters on the grounding crossarm according to the test requirements. When simulating an insulator breakdown failure, workstation 1 installs the pre-treated faulty insulator specimen, and workstation 2 installs the intact insulator. When simulating a lightning arrester breakdown failure, workstation 1 installs the intact insulator, and workstation 2 installs the pre-treated faulty lightning arrester specimen.

[0092] For example, in this application Figure 1 It is a device for simulating breakdown faults of insulators and lightning arresters. The breakdown simulation unit includes a wall bushing, a test box, a grounding crossarm, station one, station two and a high-speed camera. The outgoing line of circuit breaker B1 is introduced into the test box through the wall bushing, and is connected to the devices of station one and station two in the form of bare wires; the test box is a grounded metal box that isolates the breakdown simulation area from the external area and prevents external environmental factors from affecting the fault test results; the grounding crossarm is used to install the insulators or lightning arresters used in the test and is effectively grounded; by installing insulators or lightning arresters, station one and station two can simulate insulator breakdown faults or lightning arrester breakdown faults; the high-speed camera is installed on the inner wall of the test box to record the phenomenon of the fault point at the time of the fault, and store it synchronously with the recorded data of the fault.

[0093] It should be noted that workstation one and workstation two are only for testing different fault conditions at different locations, which does not mean that the present application is limited to testing only two workstations. Therefore, if other relevant technical personnel directly use the present application in actual scenarios, such operation should also be within the scope of protection of the present application.

[0094] In an optional embodiment, more workstations can be set up as needed to simulate more complex fault conditions. For example, workstations three and four can be set up, and the insulator and arrester breakdown fault simulations can be performed separately, but workstation three performs insulator breakdown fault simulation, and workstation four performs arrester breakdown fault simulation. At this time, the working conditions in the test box are still simulating insulator and arrester breakdown faults, but it is equivalent to two working conditions for simulating insulator breakdown faults and two working conditions for simulating arrester breakdown faults. If the simulation experiment resources are sufficient, the actual scene can even be completely restored, but similar operations based on the above operations should be within the scope of our application for protection.

[0095] It should be noted that the location of station 1 or station 2 is not limited and can be adjusted according to actual needs. For example, station 1 can be set at a location closer to the substation to simulate a fault at the head end, while station 2 can be set at a location farther from the substation to simulate a fault at the end. In addition, the settings of station 1 and station 2 can also be adjusted according to the specific needs of the test. For example, station 1 can be set at the middle end to simulate a fault in the middle section of the line.

[0096] Figure 2 It is an insulator breakdown fault simulation unit. Figure 2 As shown, pre-treated insulators are installed at station one, and intact insulators are installed at station two. At this time, the device is used to simulate insulator breakdown failure.

[0097] Figure 3 It is a lightning arrester breakdown fault simulation unit. Figure 3 As shown, a good insulator is installed at station one, and a pre-treatment lightning arrester is installed at station two. At this time, the device is used to simulate a lightning arrester breakdown failure.

[0098] Figure 4 It is a schematic diagram of the pretreatment method of faulty insulator specimens.

[0099] In an embodiment of the present application, the pre-treated faulty insulator sample includes: using a fuse to connect the metal parts at the head and tail of the insulator, such as an iron cap and a steel foot. If there is no metal part at the head end, the fuse can be connected to the groove of the topmost umbrella skirt. The connection method between the fuse and the head and tail of the insulator can be winding or single-point connection. The single-point connection is to use an insulating tape or rope to tie and fix the fuse so that the fuse is in contact with the insulator surface at only one point. The fuse should be made of a low-resistance material with a maximum total cross-section of 1mm2, such as silver, aluminum, and copper. The plane where the fuse is located should be perpendicular to the ground and at a 45° angle to the conductor.

[0100] In the embodiment of the present application, the pre-treated fault arrester sample includes: using a fuse to conduct a short-circuit current along and close to the surface of the resistor to short-circuit all functional components inside the arrester. The fuse should be made of a low-resistance material with a maximum total cross-section of 1mm2, such as silver, aluminum, and copper. Since the fault arrester may cause the outer shell to explode after the arc is ignited, damaging equipment such as high-speed cameras in the box, certain protective devices should be installed when conducting a lightning arrester breakdown fault simulation test.

[0101] In an optional embodiment, the protective device can be a metal shield that can cover the entire surface of the arrester to prevent arc spray from damaging surrounding equipment. The metal shield should have sufficient strength and heat resistance to withstand the high temperature and impact force generated by the arc. In addition, ventilation holes should be provided on the shield to discharge the gas and heat generated during the test to ensure that the temperature in the test box is not too high, thereby protecting the test equipment and personnel. The protective device can also be other forms of protective measures, such as a water curtain system or high-temperature resistant glass fiber cloth. The water curtain system can be activated at the moment of the arrester breakdown to form a water curtain, effectively absorbing the heat and shock wave generated by the arc, while reducing the impact on other equipment in the test box. High-temperature resistant glass fiber cloth can be covered around the arrester to provide additional thermal insulation protection to prevent arc spray from damaging the equipment in the test box.

[0102] In the embodiment of the present application, the pre-treated faulty insulator sample can also be prepared by preparing a sodium chloride diatomaceous earth contamination liquid of a target concentration, evenly brushing or spraying the contamination liquid onto the surface of the insulator with a spray gun, and keeping the contamination layer moist, to obtain a pre-treated faulty insulator;

[0103] In an optional embodiment, the target concentration refers to the concentration of the sodium chloride diatomaceous earth contamination solution used to simulate the contamination on the surface of the insulator. This concentration should be determined according to the needs of the experiment and the actual situation to be simulated. Generally, the choice of the target concentration depends on the pollution level to be simulated, such as light pollution, moderate pollution or heavy pollution. For example, a lower concentration solution may be used for light pollution, while a higher concentration solution may be required for heavy pollution. The method for obtaining the target concentration generally includes referring to relevant industry standards or experimental specifications. In actual operation, the appropriate concentration value can be determined by consulting relevant literature or standards. For example, reference can be made to standards such as "GB / T 26218.1-2010 Selection and sizing of high-voltage insulators used under polluted conditions Part 1: Definitions, information and basic principles", which will give typical salt density values ​​(NaCl equivalent salt density) corresponding to different pollution levels. Specifically in the experiment, if a specific pollution level needs to be simulated, the salt density value corresponding to the level can be determined first, and then the required amount of sodium chloride is calculated based on the salt density value, and dissolved in a certain amount of water to form a contamination solution. As a carrier, diatomaceous earth can absorb sodium chloride solution and help form a stable and uniform dirt layer.

[0104] In an embodiment of the present application, the pre-treated faulty lightning arrester sample can also be accelerated by aging to make the arrester resistor reach the end of its life in a short time. The treatment method is as follows: use an impulse current generator to apply a standard lightning pulse current (8 / 20μs) to the arrester resistor until it is completely aged and fails, and then assemble the aged resistor to obtain the faulty lightning arrester sample.

[0105] It should be noted that it represents the time characteristics of a standard lightning pulse waveform, which is used to describe the wavefront time and half-peak time of lightning impulse current. This waveform is very common in electrical engineering, especially in the field of lightning protection and overvoltage protection. The specific explanation is as follows: 8μs: refers to the wavefront time of the lightning current waveform, that is, the time required for the current amplitude to rise from 10% to 90%. In this example, the time for the current to rise from 10% to 90% is 8 microseconds (μs). 20μs: refers to the half-peak time of the lightning current waveform, that is, the time required for the current peak to drop to half of the peak. In this example, the time for the current to drop from the peak to half is 20 microseconds (μs). This 8 / 20μs waveform is a standard waveform for simulating lightning current specified by the International Electrotechnical Commission (IEC), which is used to test and evaluate the tolerance of electrical equipment such as lightning arresters to lightning impulse current. In the laboratory, a lightning impulse is simulated by using an impulse current generator that can generate this waveform to test the protection performance of the equipment.

[0106] In summary, the present invention proposes a device for simulating breakdown faults of insulators and lightning arresters in a distribution network, which can realize the true simulation of breakdown faults of insulators and lightning arresters in a real-life test platform of a distribution network, restore the real fault characteristics on site, and obtain a large amount of effective fault recording data in a short time, so as to promote the sample collection and fault identification technology research of breakdown faults of insulators and lightning arresters. The simulation device and method provided by the present invention can be used for testing devices such as fault arc extinguishing line selection devices and relay protection in a real-life test platform of a distribution network. The simulation device provided by the present invention can realize the controllability of the fault occurrence point by changing the position of the flexible cable clamp on the overhead line, and can simulate faults at the head end, middle end and end of the line respectively. The fault insulator or fault lightning arrester sample used in the present invention is obtained by processing intact components, and has the advantages of simplicity and repeatability, and can simulate relatively consistent fault characteristics, avoiding the influence of differences in fault simulation effects on the test results.

[0107] This embodiment also provides a method for simulating and processing breakdown faults of insulators and lightning arresters in a distribution network, which is characterized by comprising:

[0108] When conducting an insulator breakdown fault simulation test, the processing steps include:

[0109] Step 1: According to the test requirements, prepare the required faulty insulator specimen according to the faulty insulator pretreatment method, install the faulty insulator specimen on the simulation device station 1, install the intact insulator on the station 2, and connect the bare wire led out of the wall bushing to the specimens at the two stations;

[0110] Step 2: Complete the grounding operation of the simulation device, including the entire casing of the simulation device, the grounding crossarm, and other measurement and control equipment that need to be grounded;

[0111] Step 3: Connect the simulation device to the set position of the 10kV overhead line through a flexible cable and a wire clamp. Before the connection, the disconnectors D1, D2, D3 and the circuit breaker B1 are in the open state, and the opening time of the circuit breaker B1 is set according to the test requirements;

[0112] Step 4: According to the selected fault phase, close the corresponding isolating switch;

[0113] Step 5: remotely close the circuit breaker B1, turn on the breakdown simulation unit, and an insulator breakdown fault occurs at station 1;

[0114] Step 6: Circuit breaker B1 automatically opens after the set fault time, disconnects the fault phase isolation switch, and prepares for the next round of tests according to the test requirements.

[0115] When conducting a lightning arrester breakdown fault simulation test, the processing steps include:

[0116] Step 1: According to the test requirements, prepare the required fault arrester sample according to the fault arrester pretreatment method, install the intact insulator on the simulation device station 1, install the fault arrester sample on the station 2, and connect the bare wire led out from the wall bushing to the samples at the two stations;

[0117] Step 2: Complete the grounding operation of the simulation device, including the entire casing of the simulation device, the grounding crossarm, and other measurement and control equipment that need to be grounded;

[0118] Step 3: Connect the simulation device to the set position of the 10kV overhead line through a flexible cable and a wire clamp. Before the connection, the disconnectors D1, D2, D3 and the circuit breaker B1 are in the open state, and the opening time of the circuit breaker B1 is set according to the test requirements;

[0119] Step 4: According to the selected fault phase, close the corresponding isolating switch;

[0120] Step 5: Close the circuit breaker B1 remotely, turn on the breakdown simulation unit, and a lightning arrester breakdown failure occurs at station 2;

[0121] Step 6: Circuit breaker B1 automatically opens after the set fault time, disconnects the fault phase isolation switch, and prepares for the next round of tests according to the test requirements.

[0122] The above-mentioned unit modules may be embedded in or independent of a processor in a computer device in the form of hardware, or may be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to the above-mentioned modules.

[0123] This embodiment also provides a computer device, which may be a terminal, and its internal structure diagram may be as shown in FIG. Figure 6As shown. The computer device includes a processor, a memory, a communication interface, a display screen and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, an operator network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a method for processing a breakdown fault simulation device for insulators and lightning arresters in a distribution network is implemented. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covered on the display screen, or a key, trackball or touchpad set on the computer device housing, or an external keyboard, touchpad or mouse, etc.

[0124] This embodiment further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the following steps are implemented:

[0125] When conducting an insulator breakdown fault simulation test, the processing steps include:

[0126] Step 1: According to the test requirements, prepare the required faulty insulator specimen according to the faulty insulator pretreatment method, install the faulty insulator specimen on the simulation device station 1, install the intact insulator on the station 2, and connect the bare wire led out of the wall bushing to the specimens at the two stations;

[0127] Step 2: Complete the grounding operation of the simulation device, including the entire casing of the simulation device, the grounding crossarm, and other measurement and control equipment that need to be grounded;

[0128] Step 3: Connect the simulation device to the set position of the 10kV overhead line through a flexible cable and a wire clamp. Before the connection, the disconnectors D1, D2, D3 and the circuit breaker B1 are in the open state, and the opening time of the circuit breaker B1 is set according to the test requirements;

[0129] Step 4: According to the selected fault phase, close the corresponding isolating switch;

[0130] Step 5: remotely close the circuit breaker B1, turn on the breakdown simulation unit, and an insulator breakdown fault occurs at station 1;

[0131] Step 6: Circuit breaker B1 automatically opens after the set fault time, disconnects the fault phase isolation switch, and prepares for the next round of tests according to the test requirements.

[0132] When conducting a lightning arrester breakdown fault simulation test, the processing steps include:

[0133] Step 1: According to the test requirements, prepare the required fault arrester sample according to the fault arrester pretreatment method, install the intact insulator on the simulation device station 1, install the fault arrester sample on the station 2, and connect the bare wire led out from the wall bushing to the samples at the two stations;

[0134] Step 2: Complete the grounding operation of the simulation device, including the entire casing of the simulation device, the grounding crossarm, and other measurement and control equipment that need to be grounded;

[0135] Step 3: Connect the simulation device to the set position of the 10kV overhead line through a flexible cable and a wire clamp. Before the connection, the disconnectors D1, D2, D3 and the circuit breaker B1 are in the open state, and the opening time of the circuit breaker B1 is set according to the test requirements;

[0136] Step 4: According to the selected fault phase, close the corresponding isolating switch;

[0137] Step 5: Close the circuit breaker B1 remotely, turn on the breakdown simulation unit, and a lightning arrester breakdown failure occurs at station 2;

[0138] Step 6: Circuit breaker B1 automatically opens after the set fault time, disconnects the fault phase isolation switch, and prepares for the next round of tests according to the test requirements.

[0139] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

[0140] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of complete hardware embodiments, complete software embodiments, or embodiments in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code. The scheme in the embodiments of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0141] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0142] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0143] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0144] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0145] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A device for simulating breakdown faults of insulators and lightning arresters in a distribution network, characterized in that: include: Measurement and control unit and breakdown simulation unit; The measurement and control unit includes an isolating switch, a current transformer, a voltage transformer, a control and recording device, and a circuit breaker; The breakdown simulation unit includes a wall bushing, a test box, a high-speed camera, a grounding cross arm, a workstation 1 and a workstation 2; One end of the measurement and control unit is connected to the 10kV overhead line through an isolating switch, and the other end is connected to the breakdown simulation unit through circuit breaker B1.

2. The device for simulating breakdown faults of insulators and lightning arresters in a distribution network according to claim 1, characterized in that: The measurement and control unit also includes: The disconnector has three contacts D1, D2 and D3, which respectively control the connection between the A phase, B phase and C phase of the 10kV overhead line and the measurement and control unit; The isolating switch has a locking structure, and at most one contact can be closed to prevent two or three phases from being short-circuited to ground at the same time; The upper end of the disconnector is connected to a flexible cable, which is electrically connected to the 10kV overhead line through a wire clamp; When the position of the wire clamp on the overhead line is changed, the location of the simulated fault will change, and the fault can be simulated to occur at the beginning, middle or end of the line; The current transformer collects the zero-sequence current and the fault phase and non-fault phase current signals of the line; The voltage transformer collects the zero-sequence voltage of the line and the voltage signals of the fault phase and the non-fault phase; The control and recording equipment records the voltage and current signals collected by the transformer, and controls the opening and closing of circuit breaker B1 accordingly, and controls the phase and duration of the simulated fault according to the test requirements.

3. The device for simulating breakdown faults of insulators and lightning arresters in a distribution network as claimed in claim 2, characterized in that: The breakdown simulation unit also includes: The outgoing line of circuit breaker B1 is introduced into the test box through the wall bushing and connected to workstations 1 and 2 in the form of overhead bare wires; The test box is a grounded metal box that protects the test items in the box from interference from external environmental factors during the test; A high-speed camera is installed on the inner wall of the test chamber to record the phenomenon at the fault point at the time of the fault and store it synchronously with the recorded data of the fault; There are two grounding cross arms, front and rear, with reserved installation positions for insulators and lightning arresters, and effective grounding; Workstations 1 and 2 install insulators or lightning arresters on the grounding crossarm according to the test requirements. When simulating an insulator breakdown failure, workstation 1 installs the pre-treated faulty insulator specimen, and workstation 2 installs the intact insulator. When simulating a lightning arrester breakdown failure, workstation 1 installs the intact insulator, and workstation 2 installs the pre-treated faulty lightning arrester specimen.

4. The device for simulating breakdown faults of insulators and lightning arresters in a power distribution network as claimed in claim 3, characterized in that: The pre-treated fault insulator test piece comprises: Use fuses to connect the metal parts at the beginning and end of the insulator; If there is no head end metal part, connect the fuse to the groove of the topmost shed skirt; The connection method between the fuse and the first and second ends of the insulator can be winding or single-point connection. The single-point connection is to use an insulating tape or rope to tie and fix the fuse. In the insulator pretreatment, the plane where the fuse is located is at a 45° angle to the conductor.

5. The device for simulating breakdown faults of insulators and lightning arresters in a distribution network as claimed in claim 3, characterized in that: The pre-treated fault arrester test product includes: The arrester is an AC gapless metal oxide arrester, which uses a fuse to run along and closely adhere to the surface of the resistor to conduct short-circuit current and short-circuit all functional components inside the arrester; A protective device is installed in the test chamber to prevent the failure of the arrester jacket from exploding and damaging the equipment in the test chamber.

6. The device for simulating breakdown faults of insulators and lightning arresters in a power distribution network as claimed in claim 3, characterized in that: Also includes: The pretreated faulty insulator sample can also be prepared by preparing a sodium chloride diatomaceous earth contamination liquid of a target concentration, brushing the contamination liquid evenly or spraying it with a spray gun onto the surface of the insulator, and keeping the contamination layer moist, to obtain a pretreated faulty insulator; The pre-treated fault arrester sample can also apply a standard lightning pulse current to the arrester resistor through an impulse current generator until it is completely aged and fails, and then the aged resistor is assembled to obtain the pre-treated fault arrester sample.

7. A method for simulating breakdown faults of insulators and lightning arresters in a distribution network as claimed in claim 1, characterized in that: include: When conducting an insulator breakdown fault simulation test, the processing steps include: Step 1: According to the test requirements, prepare the required faulty insulator specimen according to the faulty insulator pretreatment method, install the faulty insulator specimen on the simulation device station 1, install the intact insulator on the station 2, and connect the bare wire led out of the wall bushing to the specimens at the two stations; Step 2: Complete the grounding operation of the simulation device, including the entire casing of the simulation device, the grounding crossarm, and other measurement and control equipment that need to be grounded; Step 3: Connect the simulation device to the set position of the 10kV overhead line through a flexible cable and a wire clamp. Before the connection, the disconnectors D1, D2, D3 and the circuit breaker B1 are in the open state, and the opening time of the circuit breaker B1 is set according to the test requirements; Step 4: According to the selected fault phase, close the corresponding isolating switch; Step 5: remotely close the circuit breaker B1, turn on the breakdown simulation unit, and an insulator breakdown fault occurs at station 1; Step 6: Circuit breaker B1 automatically opens after the set fault time, disconnects the fault phase isolation switch, and prepares for the next round of tests according to the test requirements.

8. The method for simulating and processing breakdown faults of insulators and lightning arresters in a distribution network according to claim 7, characterized in that: Also includes: When conducting a lightning arrester breakdown fault simulation test, the processing steps include: Step 1: According to the test requirements, prepare the required fault arrester sample according to the fault arrester pretreatment method, install the intact insulator on the simulation device station 1, install the fault arrester sample on the station 2, and connect the bare wire led out from the wall bushing to the samples at the two stations; Step 2: Complete the grounding operation of the simulation device, including the entire casing of the simulation device, the grounding crossarm, and other measurement and control equipment that need to be grounded; Step 3: Connect the simulation device to the set position of the 10kV overhead line through a flexible cable and a wire clamp. Before the connection, the disconnectors D1, D2, D3 and the circuit breaker B1 are in the open state, and the opening time of the circuit breaker B1 is set according to the test requirements; Step 4: According to the selected fault phase, close the corresponding isolating switch; Step 5: Close the circuit breaker B1 remotely, turn on the breakdown simulation unit, and a lightning arrester breakdown failure occurs at station 2; Step 6: Circuit breaker B1 automatically opens after the set fault time, disconnects the fault phase isolation switch, and prepares for the next round of tests according to the test requirements.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 7 to 8 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 7 to 8 are implemented.

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