An arc suppression device compatible with arc suppression coil operation and a phase error detection and prevention method

Abstract

The present invention provides an arc suppression device and a phase judgment and error prevention method that are compatible with the operation of an arc suppression coil, and relates to the technical field of power supply equipment. The device includes a grounding transformer, an arc suppression coil, a variable impedance module, and a fault grounding phase selection module; a pre-circuit breaker is connected in series between the grounding transformer and the three-phase line of the busbar, the neutral point of the grounding transformer is connected to one end of the arc suppression coil, the other end of the arc suppression coil is connected to one end of the variable impedance module, and the output end of the variable impedance module is grounded; the variable impedance module includes a plurality of current limiting impedance sub-modules connected in parallel, and each current limiting impedance sub-module includes a current limiting impedance and an impedance access switch connected in series with each other; the fault grounding phase selection module is used to identify the fault phase that generates a single-phase grounding fault when a grounding fault occurs. This application uses a variable impedance module to introduce a damping effect, consume the resonance capacity, and suppress the increase in neutral point voltage, thereby reducing the resonance phenomenon that may be generated by the arc suppression coil.

Description

Technical Field

[0001] The present invention relates to the technical field of power supply equipment, and in particular to an arc suppression device compatible with arc suppression coil operation and a phase error prevention method. Background Art

[0002] At present, in the process of grounding fault in distribution network, intelligent processing is introduced to identify and process the fault phase of single-phase grounding fault, so as to reduce the fault processing time and increase the accuracy of fault processing.

[0003] In the related technology, there is a publication number CN201430438Y, and the invention name is an arc extinguishing device, which includes an arc extinguishing coil device, a fault phase grounding device and a controller; the arc extinguishing coil device includes an arc extinguishing coil, a current transformer and a voltage transformer, one end of the current transformer is connected to the grounding transformer used to lead out the neutral point of the power grid, the other end of the current transformer is connected to one end of the arc extinguishing coil, the other end of the arc extinguishing coil is grounded, and the current transformer is connected to the grounding transformer; the controller is connected to the current transformer and the voltage transformer respectively, and is used to collect the current signal and voltage signal measured by the current transformer and the voltage transformer, and control the arc extinguishing coil and / or the fault phase grounding device to extinguish the arc according to the current signal and voltage signal and the ground voltage of each phase line in the power grid.

[0004] Regarding the above technical solution, there are still the following shortcomings: in the process of generating a single-phase grounding fault, when the capacitive current to ground is close to the inductive current of the arc suppression coil, the arc suppression coil may produce resonance, resulting in the risk of overvoltage in the arc suppression coil. Summary of the Invention

[0005] In order to reduce the resonance phenomenon that may be caused by the arc suppression coil, the present application provides an arc suppression device and a phase error prevention method that are compatible with the operation of the arc suppression coil.

[0006] In the first aspect, the present application provides an arc suppression device compatible with arc suppression coil operation, which adopts the following technical solution:

[0007] An arc suppression device compatible with arc suppression coil operation, the device comprising a grounding transformer, an arc suppression coil, a variable impedance module, and a fault grounding phase selection module;

[0008] A pre-circuit breaker 1 is connected in series between the grounding transformer 1 and the three-phase line of the busbar, the neutral point of the grounding transformer 1 is connected to one end of the arc suppression coil, the other end of the arc suppression coil is connected to one end of the variable impedance module, and the output end of the variable impedance module is grounded;

[0009] The variable impedance module includes a plurality of current-limiting impedance sub-modules connected in parallel, each current-limiting impedance sub-module includes a current-limiting impedance and an impedance access switch, and the current-limiting impedance and the impedance access switch are connected in series;

[0010] The fault grounding phase selection module is used to identify the fault phase that generates a single-phase grounding fault when a ground fault occurs.

[0011] Secondly, the application also provides a phase error detection and prevention method for an arc suppression device compatible with arc suppression coil operation, which adopts the following technical solution:

[0012] A phase error detection and prevention method for an arc suppression device compatible with arc suppression coil operation, wherein each of the three-phase lines of the busbar is equipped with a phase current transformer, and the method comprises:

[0013] If short-circuit fault information fed back from the feeder side of the power distribution system is received, the front circuit breaker is controlled to close;

[0014] The following steps are executed repeatedly until all phase switches are marked as filtered or the arc suppression switches are closed:

[0015] generating fault phase identification information based on the phase current values ​​fed back by the phase line current transformers obtained in real time;

[0016] Controlling the corresponding phase switch in the arc-extinguishing phase circuit breaker to close according to the fault phase identification information, and adding a filtered mark to the phase switch currently in the closed state;

[0017] receiving the phase selection current feedback information fed back by the current transformer 1, and generating phase selection judgment information carrying a correct identification mark or an incorrect identification mark according to the phase selection current feedback information;

[0018] If the phase selection judgment information carries a correct identification mark, controlling the arc suppression switch to close;

[0019] If the phase selection judgment information carries an identification error flag, the phase switch currently in the closed state is disconnected.

[0020] Thirdly, the application also provides a phase error detection and prevention system for arc suppression devices compatible with arc suppression coil operation, which adopts the following technical solutions:

[0021] A phase error detection and prevention system for an arc extinguishing device compatible with arc extinguishing coil operation, the system comprising:

[0022] An information receiving module controls the front circuit breaker to close upon receiving short circuit fault information fed back from the feeder side of the power distribution system;

[0023] The following steps are executed repeatedly until all phase switches are marked as filtered or the arc suppression switches are closed:

[0024] A fault identification and classification module is configured to generate fault phase identification information based on phase current values ​​fed back by the phase current transformers obtained in real time;

[0025] an identification adding module, configured to control the closing of the corresponding phase switch in the arc-extinguishing phase circuit breaker according to the fault phase identification information, and to add a filtered identification to the phase switch currently in the closed state;

[0026] an information receiving module for receiving the phase selection current feedback information fed back by the current transformer 1 and generating phase selection judgment information carrying a correct identification mark or an incorrect identification mark according to the phase selection current feedback information;

[0027] a fault identification and classification module, which controls the arc suppression switch to close if the phase selection judgment information carries a correct identification mark;

[0028] The fault identification and classification module disconnects the phase switch currently in the closed state if the phase selection judgment information carries an identification error flag.

[0029] In summary, this application includes at least one of the following beneficial technical effects:

[0030] When a single-phase grounding fault occurs on the feeder side of the distribution system, the front circuit breaker is quickly controlled to close, and the arc suppression coil compensates for the system's ground capacitance current, thereby suppressing the arc grounding overvoltage and slowing the rise in the fault phase recovery voltage. At this time, the variable impedance module introduces a damping effect, consumes the resonant capacity, and suppresses the rise in neutral point voltage, thereby reducing the resonance phenomenon that may be caused by the arc suppression coil. At the same time, the series variable impedance module injects an additional resistive current component, which is 90° out of phase with the inductive compensation current, significantly increasing the zero-sequence current of the fault line and improving the detection sensitivity of the line selection device.

[0031] When the arc suppression coil is connected to the fault circuit to provide inductive compensation current, it will generate a lot of heat due to its own impedance. At the same time, after the arc suppression coil has been in use for a long time, its own internal resistance increases, which may increase the possibility of damage to the arc suppression coil due to severe self-heating. In this application, by generating an estimated compensation current threshold and an estimated risk state probability, the heating risk of the arc suppression coil is estimated, thereby reducing the probability of damage to the arc suppression coil due to heat. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of 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 work.

[0033] Figure 1 This is a circuit diagram of an arc suppression device that is compatible with the operation of an arc suppression coil provided in an embodiment of the present application.

[0034] Figure 2 It is a flow chart of a phase judgment and error prevention method for an arc extinguishing device that is compatible with the operation of an arc extinguishing coil, provided in an embodiment of the present application.

[0035] Figure 3 It is a supplementary flow chart of the phase judgment and error prevention method of the arc extinguishing device compatible with the arc extinguishing coil operation provided in the embodiment of the present application.

[0036] Figure 4 This is a flow chart of estimating the heating risk of arc suppression coils provided in an embodiment of the present application.

[0037] Figure 5 This is a flow chart of generating a compensation current threshold provided in an embodiment of the present application.

[0038] Explanation of the accompanying symbols: 1. Variable impedance module; 2. Fault grounding phase selection module; 3. Fault grounding line selection module. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solutions and advantages of the present invention clearer, the following Figure 1-5 The embodiments of the present invention are described in further detail.

[0040] This application provides an arc suppression device compatible with arc suppression coil operation, such as Figure 1 As shown, the device includes a pre-circuit breaker, a grounding transformer, an arc suppression coil, a variable impedance module 1, a fault grounding phase selection module 2 and a fault grounding line selection module 3.

[0041] The three-phase input terminal of the front circuit breaker 1 is connected to the three-phase line of the busbar one by one, the three-phase output terminal of the front circuit breaker 1 is connected to the three-phase input terminal of the grounding transformer 1 by one one, the neutral point of the grounding transformer 1 is connected to one end of the arc suppression coil, the other end of the arc suppression coil is connected to one end of the variable impedance module, and the output end of the variable impedance module is grounded.

[0042] When a single-phase ground fault occurs on the feeder side of the distribution system, the pre-circuit breaker is quickly closed. The arc suppression coil compensates for the system's ground capacitance current, suppressing arc-flash grounding overvoltage and slowing the rise in the fault phase's recovery voltage. At this point, variable impedance module 1 introduces a damping effect, dissipating resonant capacity and suppressing the rise in neutral-point voltage, thereby reducing the resonance that may be caused by the arc suppression coil. Simultaneously, the series-connected variable impedance module 1 injects an additional resistive current component, 90° out of phase with the inductive compensation current. This significantly increases the zero-sequence current of the fault line and improves the detection sensitivity of the line selection device.

[0043] The line connecting the arc suppression coil to the variable impedance module 1 is also equipped with a second current transformer, which is used to monitor the compensation current of the arc suppression coil.

[0044] The variable impedance module 1 comprises multiple current-limiting impedance submodules connected in parallel. Each current-limiting impedance submodule includes a current-limiting impedance and an impedance access switch, which are connected in series. The resistance value is dynamically adjusted by real-time monitoring of the neutral point voltage and fault current. For example, the total resistance of the variable impedance module 1 is reduced during resonant overvoltage, while the total resistance of the variable impedance module 1 is temporarily increased during fault line selection to highlight the fault characteristics.

[0045] Fault-grounded phase selection module 2 identifies the faulty phase that causes a single-phase ground fault. It includes a second pre-circuit breaker, an arc-suppression phase breaker, a current-limiting resistor, and an arc-suppression switch. To facilitate preliminary phase selection for ground faults, each of the three busbar phases is equipped with a phase current transformer.

[0046] The three-phase input terminals of pre-circuit breaker 2 are connected one-to-one with the three-phase lines of the busbar. The arc-suppression phase-splitting circuit breaker includes three phase switches corresponding to the three-phase lines of the busbar. The input terminals of multiple phase switches in the arc-suppression phase-splitting circuit breaker are connected to the three-phase output terminals of pre-circuit breaker 2. One end of the current-limiting resistor is connected to the output terminals of multiple phase switches, and the other end of the current-limiting resistor is grounded. The arc-suppression switch is connected in parallel with the current-limiting resistor. A current transformer 1 is installed on the common ground line between the current-limiting resistor and the arc-suppression switch.

[0047] The fault grounding line selection module 3 includes a three-phase contactor and a grounding transformer 2 with impedance. The three-phase input terminals of the three-phase contactor are respectively connected to the three-phase output terminals of the pre-circuit breaker 2, and the output terminals of the three-phase contactor are connected to the three-phase input terminals of the grounding transformer 2. The neutral point of the grounding transformer 2 is grounded; the grounding line of the grounding transformer 2 is equipped with a current transformer 3.

[0048] After a short-circuit fault current is detected on the distribution system feeder, the front circuit breaker 1 and the front circuit breaker 2 are controlled to close, and the fault phase selection and fault line selection are further performed through the fault grounding phase selection module 2 and the fault grounding line selection module 3.

[0049] Specifically, the arc suppression device is also equipped with a main controller, which receives current information fed back by current transformers 1, 2, 3, and multiple phase current transformers. The main controller is used to control the opening and closing of the arc suppression phase circuit breaker, pre-circuit breaker 1, pre-circuit breaker 2, arc suppression switch, and impedance access switch.

[0050] During the fault phase selection process of the main controller, the fault phase selection submodule first closes a phase switch in the arc-extinguishing phase circuit breaker, and then monitors the current flowing through the current limiting resistor and the related vector relationship through the current transformer, so as to determine whether the phase selection is accurate.

[0051] If the fault phase is correct, the arc suppression switch is closed to ground the fault phase. If the phase is incorrect, the closed phase switch is opened and another phase switch is selected to complete the phase selection again.

[0052] An embodiment of the present application also provides a phase error judgment and prevention method for an arc extinguishing device compatible with arc extinguishing coil operation. The method can be applied to a phase error judgment and prevention system for an arc extinguishing device compatible with arc extinguishing coil operation. The phase error judgment and prevention system for an arc extinguishing device compatible with arc extinguishing coil operation can be composed of a main controller, current transformer one, current transformer two, current transformer three and multiple phase line current transformers. The executor of the method can be the main controller in the phase error judgment and prevention system for an arc extinguishing device compatible with arc extinguishing coil operation.

[0053] The following will be combined with specific implementation methods. Figure 2 The processing flow shown in the figure is described in detail, and the content can be as follows:

[0054] Step S101: If short circuit fault information fed back from the feeder side of the power distribution system is received, the front circuit breaker is controlled to be closed.

[0055] During implementation, when the main controller receives the short-circuit fault information fed back from the feeder side of the distribution system, the main controller controls the front circuit breaker 1 and the front circuit breaker 2 to close, so that the arc suppression coil, the fault grounding phase selection module 2 and the fault grounding line selection module 3 can work.

[0056] The following steps are executed repeatedly until all phase switches are marked as filtered or the arc suppression switches are closed:

[0057] Step S102: generating fault phase identification information based on the phase current values ​​fed back by the multiple phase line current transformers acquired in real time.

[0058] In implementation, after receiving the short-circuit fault information, the main controller loops through the following steps until all phase switches are marked as filtered or the arc suppression switch is closed, and then exits the loop after processing all steps in this loop.

[0059] Specifically, the main controller obtains the phase current values ​​fed back by multiple phase line current transformers in real time, and then compares the multiple phase current values ​​obtained in real time with the fault current threshold. If the phase current value of a phase is greater than the fault current threshold, the phase is identified as a fault phase with fault operation, and the current bus three-phase line is marked as a fault operation state, so as to generate fault phase identification information carrying fault phase calibration.

[0060] Step S103: Control the corresponding phase switch in the arc-extinguishing phase circuit breaker to close according to the fault phase identification information, and add a filtered mark to the phase switch that is currently in the closed state.

[0061] During implementation, the main controller uses the fault phase identification information to control the corresponding phase switch in the arc-extinguishing phase circuit breaker to close, and then adds a filtered mark to the phase switch that is currently in the closed state.

[0062] Step S104: receiving phase selection current feedback information fed back by the current transformer 1, and generating phase selection judgment information carrying a correct identification mark or an incorrect identification mark according to the phase selection current feedback information.

[0063] During implementation, after closing the corresponding phase switch, the main controller receives the phase selection current feedback information fed back by the current transformer, and generates phase selection judgment information carrying the correct identification mark or the wrong identification mark through the current value and related vector relationship in the phase selection current feedback information.

[0064] Step S105: If the phase selection judgment information carries a correct identification mark, the arc suppression switch is controlled to close.

[0065] During implementation, when the main controller recognizes that there is a correct identification mark in the current phase selection judgment information, it controls the arc suppression switch to close, so that the fault phase is metallically grounded, and the current of the fault phase flows to the ground through the arc suppression switch, thereby reducing the current flowing through the fault phase at the feeder end and reducing the impact of the single-phase short circuit fault.

[0066] Step S106: If the phase selection judgment information carries an identification error flag, the phase switch currently in the closed state is disconnected.

[0067] During implementation, if the main controller identifies that there is an error identifier in the current phase selection judgment information, it will disconnect the phase switch that is currently in the closed state.

[0068] At this time, if there are still phase switches that have not been added with the filtered identifier, the above steps S102 to S104 are repeated until a correct identifier is found in the phase selection judgment information, and then step S105 is executed.

[0069] If the three phase switches are all added with the filtered flag, the loop ends.

[0070] Optionally, in this application, after the phase selection judgment information has a correct identification mark, there is also the following Figure 3 The specific operation process is as follows:

[0071] Step S107 : after waiting for a preset instantaneous delay time, the phase switch currently in the closed state is controlled to open, and the operating state of the busbar three-phase line is identified by using the currently acquired multiple phase current values.

[0072] In practice, after screening out the faulty phase, the main controller waits for a preset instantaneous delay time, where the preset instantaneous delay time can be 50ms, 80ms, 2s, etc.

[0073] After waiting for the instantaneous delay time, the main controller controls the arc suppression switch and the phase switch in the closed state to open in turn.

[0074] Then the main controller again compares the currently obtained multiple phase current value information with the fault current threshold to determine whether the single-phase ground short circuit fault disappears after the instantaneous delay time. If the single-phase ground short circuit fault disappears, the current single-phase ground short circuit fault is recorded as a transient fault, and the busbar three-phase line is in normal operation at this time; if the single-phase ground short circuit fault does not disappear, the current single-phase ground short circuit fault is recorded as a permanent fault, and the busbar three-phase line is in fault operation at this time.

[0075] Step S108: If normal operation is identified in the operating state of the busbar three-phase line, the front circuit breaker is controlled to open.

[0076] During implementation, if the main controller identifies that the operating state of the busbar three-phase line is normal operation, that is, the current single-phase short circuit fault is a transient fault, it controls the front circuit breaker 1 and the front circuit breaker 2 to open.

[0077] Step S109: If a faulty operation is identified in the operating status of the bus three-phase line, the operating status of the bus three-phase line is periodically obtained with a preset dwell time until the operating status of the bus three-phase line is normal, and the front circuit breaker is controlled to open, or the bus three-phase line has a faulty operation time that is greater than the preset arc suppression coil working time, and the front circuit breaker is controlled to open.

[0078] During implementation, if the main controller identifies that the operating state of the bus three-phase line is fault operation, that is, the current single-phase short circuit fault is a permanent fault, the main controller controls the opening switch and arc suppression switch corresponding to the fault to close.

[0079] Furthermore, the main controller performs periodic detection and evaluation processing on the operating status of the bus three-phase line with a preset dwell time, and the dwell time may be 10 minutes. Specifically:

[0080] The main controller will open the disconnect switch and arc suppression switch corresponding to the fault again after every 10 minutes, and then obtain the operating status of the bus three-phase line to determine whether the fault has been eliminated.

[0081] If the fault is eliminated, the front circuit breaker 1 and the front circuit breaker 2 are controlled to open and the cycle stops.

[0082] If the fault has not been eliminated, the arc suppression switch and the target opening switch are controlled to close, and then the next 10-minute cycle is carried out.

[0083] When the faulty operation duration exceeds the preset arc suppression coil operating time, the cycle stops and the main controller controls the front circuit breaker to open. The arc suppression coil operating time is generally between 1 and 2 hours, and the specific time here can be set according to different equipment.

[0084] Optionally, in this application, after the front circuit breaker 1 and the front circuit breaker 2 are closed, there is also the following Figure 4 The specific operation process is as follows:

[0085] Step S201, obtaining the operating temperature value of the arc suppression coil and the current compensation current value fed back by the second current transformer in real time.

[0086] During implementation, the main controller obtains the operating temperature value of the arc suppression coil fed back by the temperature sensor in real time, and at the same time, the main controller also obtains the current compensation current value fed back by the second current transformer.

[0087] Step S202: According to the current compensation current value, the corresponding target theoretical operating temperature value is matched in the preset arc suppression coil theoretical temperature rise data. The arc suppression coil theoretical temperature rise data is used to reflect the correspondence between the theoretical compensation current value and the theoretical operating temperature value.

[0088] In practice, the main controller is pre-set with arc suppression coil theoretical temperature rise data, which is used to reflect the correspondence between the theoretical compensation current value and the theoretical operating temperature value. The arc suppression coil theoretical temperature rise data here can be obtained from a constant temperature environment in a laboratory.

[0089] The main controller matches the corresponding theoretical operating temperature value in the arc suppression coil theoretical temperature rise data with the current compensation current value, and calls the theoretical operating temperature value matched here the target historical operating temperature value.

[0090] Step S203 : Calculate and generate a current estimated temperature difference value based on the current actual operating temperature value and the target theoretical operating temperature value.

[0091] During implementation, the main controller calculates and generates the current estimated temperature difference by subtracting the actual operating temperature value fed back by the temperature sensor from the target theoretical operating temperature value.

[0092] Step S204: Obtain historical compensation current data and historical operating temperature data of the current arc suppression coil.

[0093] During implementation, the main controller will obtain the historical compensation current data and historical operating temperature data of the current arc suppression coil from the storage database or the specified network address. The historical compensation current data includes multiple historical compensation current values, and the historical operating temperature data includes multiple historical operating temperature values.

[0094] Step S205 , generating historical estimated temperature difference information based on historical compensation current data, historical operating temperature data, and arc suppression coil theoretical temperature rise data.

[0095] In practice, the main controller uses historical compensation current data to match multiple theoretical compensation current values ​​with the arc suppression coil theoretical temperature rise data. The main controller then subtracts the corresponding theoretical compensation current value from the historical operating temperature value to calculate a historical estimated temperature difference. The controller then aggregates these multiple historical estimated temperature differences to generate historical estimated temperature difference information.

[0096] Step S206 , generating a compensation current threshold value based on the historical estimated temperature difference information, the current estimated temperature difference value, and a preset upper temperature threshold value.

[0097] In implementation, the main controller calculates and generates an average estimated temperature difference value based on a plurality of historical estimated temperature difference values ​​and a current estimated temperature difference value.

[0098] The average estimated temperature difference is then subtracted from the upper temperature threshold to generate the target temperature value. The target temperature value is then used to match the corresponding compensation current threshold in the arc suppression coil theoretical temperature rise data.

[0099] Step S207: obtaining the same type of compensation current data in the distribution network at the same distribution voltage level as the current arc suppression device.

[0100] During implementation, the main controller obtains historical compensation power data at the same distribution voltage level as the current arc suppression device in the distribution network from the specified network address. The compensation current data here is called the same type of compensation current data.

[0101] Step S208 : generating estimated risk status information based on the same type of compensation current data and the compensation current threshold.

[0102] During implementation, the main controller pre-divides multiple current division gradients, and then uses the distribution of the same type of compensation current in each current division gradient to generate the distribution probability within each current division gradient. Then, the distribution probability corresponding to the current division gradient where the compensation current threshold is located is used as the risk probability to generate estimated risk state information carrying risk probability.

[0103] When the arc suppression coil is connected to the fault circuit to provide inductive compensation current, it will generate a lot of heat due to its own impedance. At the same time, after the arc suppression coil is put into use for a long time, its own internal resistance increases, which may increase the possibility of damage to the arc suppression coil due to severe self-heating. In this application, the estimated compensation current threshold and the estimated risk state probability are generated by the above calculation method to estimate the heating risk of the arc suppression coil, thereby reducing the probability of damage to the arc suppression coil due to heat.

[0104] Optionally, in step S206, there is also the following Figure 5 The specific operation process is as follows:

[0105] Step S301 : Calculate and generate a plurality of temperature difference gradient change amounts based on historical estimated temperature difference information and the current estimated temperature difference.

[0106] During implementation, the main controller subtracts two adjacent historical estimated temperature difference values ​​from each other on the timeline, and subtracts the most recent historical estimated temperature difference value on the timeline from the current estimated temperature difference value, to generate multiple temperature difference gradient changes in the historical estimated temperature difference value information and the current estimated temperature difference value.

[0107] Step S301 : calculating and generating an estimated gradient change amount based on a plurality of temperature difference gradient change amounts.

[0108] In implementation, the main controller calculates and generates the estimated gradient change amount based on the average value of the temperature difference gradient change amount.

[0109] Step S302 : Calculate and generate an estimated temperature difference value based on the estimated gradient change amount and the current estimated temperature difference value.

[0110] In implementation, the main controller superimposes the estimated gradient change and the current estimated temperature difference to generate the estimated temperature difference.

[0111] Step S303 : calculating and generating a compensation current threshold value based on the estimated temperature difference and the upper temperature limit threshold value.

[0112] Specifically, the processing flow in step S301 is as follows:

[0113] Calculate and generate a target temperature threshold corresponding to the upper temperature threshold based on the upper temperature threshold and the estimated temperature difference;

[0114] According to the target temperature threshold, the corresponding compensation current threshold is matched in the arc suppression coil theoretical temperature rise data.

[0115] In an implementation, the main controller subtracts the estimated temperature difference from the upper temperature threshold to calculate and generate a target temperature threshold corresponding to the upper temperature threshold.

[0116] Then the main controller matches the corresponding compensation current value in the arc suppression coil theoretical temperature rise data with the target temperature threshold, and the matched compensation current value is called the compensation current threshold.

[0117] Optionally, in step S208, the following processing is also performed. The specific operation flow is as follows:

[0118] Calculate and generate a compensation current distribution rate of the same type of compensation current values ​​within each current partition gradient based on multiple compensation current values ​​of the same type in the same type of compensation current data and the pre-divided current partition gradient;

[0119] Divide the gradient according to the target current matching corresponding to the compensation current threshold;

[0120] According to the compensation current distribution rate corresponding to the target current division gradient, estimated risk status information is generated.

[0121] In practice, the main controller is pre-divided into multiple current division gradients. When the main controller obtains the same type of compensation current data, it calculates the probability of the same type of compensation current value distribution in each current division gradient, which is called the compensation current distribution rate.

[0122] Then the main controller matches the current division gradient where the compensation current threshold is located, and the matched current division gradient is called the target current division gradient.

[0123] The main controller then uses the compensation current distribution rate corresponding to the target current division gradient as the risk state probability, and generates estimated risk state information carrying the risk state probability.

[0124] The present application also discloses a phase error detection and prevention system for an arc suppression device compatible with arc suppression coil operation, characterized in that the system includes:

[0125] The information receiving module controls the front circuit breaker to close if it receives the short circuit fault information fed back from the feeder side of the power distribution system;

[0126] The following steps are executed repeatedly until all phase switches are marked as filtered or the arc suppression switches are closed:

[0127] A fault identification and classification module is used to generate fault phase identification information based on the phase current values ​​fed back by multiple phase line current transformers obtained in real time;

[0128] An identification adding module is used to control the closing of the corresponding phase switch in the arc-extinguishing phase circuit breaker according to the fault phase identification information, and to add a filtered identification to the phase switch currently in the closed state;

[0129] An information receiving module receives the phase selection current feedback information fed back by the current transformer 1, and generates phase selection judgment information carrying a correct identification mark or an incorrect identification mark according to the phase selection current feedback information;

[0130] The fault identification and classification module controls the arc suppression switch to close if the phase selection judgment information carries a correct identification mark;

[0131] The fault identification and classification module disconnects the phase switch currently in the closed state if the phase selection judgment information carries an identification error flag.

[0132] Optionally, the system may also be used for:

[0133] The fault identification and classification module controls the phase switch currently in the closed state to open after waiting for the preset instantaneous delay time, and identifies the operating status of the busbar three-phase line based on the currently acquired multiple phase current values;

[0134] The fault identification and classification module controls the front circuit breaker to open if normal operation is identified in the operating state of the busbar three-phase line;

[0135] The fault identification and classification module, if a fault operation is identified in the operating status of the bus three-phase line, will periodically obtain the operating status of the bus three-phase line with a preset dwell time until the operating status of the bus three-phase line is normal, and control the front circuit breaker to open, or the bus three-phase line has a fault operation time greater than the preset arc suppression coil working time, and control the front circuit breaker to open.

[0136] Optionally, the system may also be used for:

[0137] The information receiving module is used to obtain the operating temperature value of the arc suppression coil and the current compensation current value fed back by the current transformer 2 in real time;

[0138] The data matching module is used to match the corresponding target theoretical operating temperature value in the preset arc suppression coil theoretical temperature rise data according to the current compensation current value. The arc suppression coil theoretical temperature rise data is used to reflect the corresponding relationship between the theoretical compensation current value and the theoretical operating temperature value;

[0139] A data calculation module is used to calculate and generate a current estimated temperature difference based on the current actual operating temperature value and the target theoretical operating temperature value;

[0140] An information receiving module is used to obtain historical compensation current data and historical operating temperature data of the current arc suppression coil;

[0141] A data calculation module is used to generate historical estimated temperature difference information based on historical compensation current data, historical operating temperature data, and arc suppression coil theoretical temperature rise data;

[0142] A data calculation module is used to generate a compensation current threshold based on historical estimated temperature difference information, current estimated temperature difference and a preset upper temperature threshold;

[0143] An information receiving module is used to obtain the same type of compensation current data at the same distribution voltage level as the current arc suppression device in the distribution network;

[0144] The data matching module is used to generate estimated risk status information based on the same type of compensation current data and compensation current threshold.

[0145] Optionally, the system is specifically used for:

[0146] A data calculation module is used to calculate and generate multiple temperature difference gradient changes based on historical estimated temperature difference information and current estimated temperature difference;

[0147] A data calculation module is used to calculate and generate an estimated gradient change amount based on multiple temperature difference gradient change amounts;

[0148] A data calculation module is used to calculate and generate an estimated temperature difference based on the estimated gradient change and the current estimated temperature difference;

[0149] The data calculation module is used to calculate and generate a compensation current threshold based on the estimated temperature difference and the temperature upper limit threshold.

[0150] Optionally, the system is specifically used for:

[0151] A data calculation module is used to calculate and generate a target temperature threshold corresponding to the upper temperature threshold based on the upper temperature threshold and the estimated temperature difference;

[0152] The data matching module is used to match the corresponding compensation current threshold in the arc suppression coil theoretical temperature rise data according to the target temperature threshold.

[0153] Optionally, the system is specifically used for:

[0154] A data matching module is used to calculate and generate a compensation current distribution rate of the same type of compensation current values ​​within each current partition gradient based on multiple same type compensation current values ​​in the same type of compensation current data and the pre-divided current partition gradient;

[0155] A data matching module, used to match the corresponding target current division gradient according to the compensation current threshold;

[0156] The data matching module is used to generate estimated risk status information based on the compensation current distribution rate corresponding to the target current division gradient.

[0157] The main controller can vary significantly depending on its configuration or performance. It may include one or more central processing units (e.g., one or more processors), memory, and one or more storage media (e.g., one or more mass storage devices) for storing applications or data. The memory and storage media may be either transient or persistent. The program stored on the storage media may include one or more modules (not shown), each of which may include a series of instructions operating on the main controller.

[0158] The main controller may also include one or more power supplies, one or more wired or wireless network interfaces, one or more input and output interfaces, one or more keyboards, and / or one or more operating systems.

[0159] The main controller may include a memory and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by one or more processors. The one or more programs include the processing of the main controller in the arc extinguishing device phase judgment and error prevention method for performing the above-mentioned compatible arc extinguishing coil operation.

[0160] Those skilled in the art will understand that all or part of the steps to implement the above embodiments may be accomplished by hardware, or may be accomplished by instructing the relevant hardware through a program, and the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, etc.

[0161] Although the present invention is disclosed as above, the protection scope of the present invention is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. An arc extinguishing device compatible with arc extinguishing coil operation, characterized in that: The device comprises a grounding transformer, an arc suppression coil, a variable impedance module (1) and a fault grounding phase selection module (2); A pre-circuit breaker 1 is connected in series between the grounding transformer 1 and the three-phase line of the busbar, the neutral point of the grounding transformer 1 is connected to one end of the arc suppression coil, the other end of the arc suppression coil is connected to one end of the variable impedance module (1), and the output end of the variable impedance module (1) is grounded; The variable impedance module (1) comprises a plurality of current limiting impedance submodules connected in parallel with each other, each current limiting impedance submodule comprises a current limiting impedance and an impedance access switch, and the current limiting impedance and the impedance access switch are connected in series; The fault grounding phase selection module (2) is used to identify the fault phase that generates a single-phase grounding fault when a grounding fault occurs; A second current transformer is installed on the line connecting the arc suppression coil to the variable impedance module (1); A phase error detection and prevention method for an arc extinguishing device using an arc extinguishing coil compatible with the arc extinguishing device is provided, the method comprising: If short-circuit fault information fed back from the feeder side of the power distribution system is received, the front circuit breaker is controlled to close; Real-time acquisition of the operating temperature value of the arc suppression coil and the current compensation current value fed back by the second current transformer; According to the current compensation current value, a corresponding target theoretical operating temperature value is matched in the preset arc suppression coil theoretical temperature rise data, wherein the arc suppression coil theoretical temperature rise data is used to reflect the corresponding relationship between the theoretical compensation current value and the theoretical operating temperature value; Calculating and generating a current estimated temperature difference value based on the current actual operating temperature value and the target theoretical operating temperature value; Obtaining historical compensation current data and historical operating temperature data of the arc suppression coil; Generate historical estimated temperature difference information based on the historical compensation current data, the historical operating temperature data, and the arc suppression coil theoretical temperature rise data; generating a compensation current threshold value based on the historical estimated temperature difference information, the current estimated temperature difference value, and a preset upper temperature limit threshold value; Obtain the same type of compensation current data in the distribution network at the same distribution voltage level as the current arc suppression device; Estimated risk status information is generated according to the same type of compensation current data and the compensation current threshold.

2. The device according to claim 1, characterized in that: The fault grounding phase selection module (2) comprises an arc-extinguishing phase circuit breaker, a current-limiting resistor and an arc-extinguishing switch; The arc-extinguishing phase-splitting circuit breaker includes three phase-splitting switches corresponding to the three-phase lines of the busbar, and the arc-extinguishing phase-splitting circuit breaker is connected to the three-phase lines of the busbar; One end of the current limiting resistor is connected to the output ends of multiple phase switches, the other end of the current limiting resistor is grounded, the arc suppression switch is connected in parallel to the current limiting resistor, and a current transformer is installed on the common grounding line of the current limiting resistor and the arc suppression switch.

3. A phase judgment and error prevention method for an arc extinguishing device compatible with arc extinguishing coil operation, using the arc extinguishing device described in claim 2, characterized in that: Phase current transformers are installed on the three-phase lines of the busbar. After controlling the front circuit breaker to close, the method further includes: The following steps are executed repeatedly until all phase switches are marked as filtered or the arc suppression switches are closed: generating fault phase identification information based on the phase current values ​​fed back by the phase line current transformers obtained in real time; Controlling the corresponding phase switch in the arc-extinguishing phase circuit breaker to close according to the fault phase identification information, and adding a filtered mark to the phase switch currently in the closed state; receiving the phase selection current feedback information fed back by the current transformer 1, and generating phase selection judgment information carrying a correct identification mark or an incorrect identification mark according to the phase selection current feedback information; If the phase selection judgment information carries a correct identification mark, controlling the arc suppression switch to close; If the phase selection judgment information carries an identification error flag, the phase switch currently in the closed state is disconnected.

4. The method according to claim 3, characterized in that After the phase selection judgment information contains a correct identification mark, the method further includes: After waiting for the preset instantaneous delay time, the phase switch currently in the closed state is controlled to open, and the operating status of the busbar three-phase line is identified by the currently acquired multiple phase current values; If normal operation is identified in the operating state of the busbar three-phase line, controlling the front circuit breaker to open; If a faulty operation is identified in the operating status of the bus three-phase line, the operating status of the bus three-phase line is periodically obtained with a preset dwell time until the operating status of the bus three-phase line is normal, and the front circuit breaker is controlled to open; or if the faulty operation time of the bus three-phase line is greater than the preset arc suppression coil working time, the front circuit breaker is controlled to open.

5. The method according to claim 3, characterized in that The generating of the compensation current threshold according to the historical estimated temperature difference information, the current estimated temperature difference and a preset upper temperature threshold includes: Calculating and generating a plurality of temperature difference gradient change amounts according to the historical estimated temperature difference information and the current estimated temperature difference; Calculating and generating an estimated gradient change amount based on the plurality of temperature difference gradient change amounts; Calculating and generating an estimated temperature difference value based on the estimated gradient change amount and the current estimated temperature difference value; A compensation current threshold is calculated and generated according to the estimated temperature difference and the upper temperature limit threshold.

6. The method according to claim 5, characterized in that The calculating and generating the compensation current threshold value according to the estimated temperature difference and the upper temperature limit threshold value includes: Calculating and generating a target temperature threshold corresponding to the upper temperature threshold according to the upper temperature threshold and the estimated temperature difference; According to the target temperature threshold, a corresponding compensation current threshold is matched in the arc suppression coil theoretical temperature rise data.

7. The method according to claim 6, characterized in that The generating of estimated risk status information according to the same type of compensation current data and the compensation current threshold includes: Calculating and generating a compensation current distribution rate of the same type of compensation current values ​​in each current partition gradient according to a plurality of same type of compensation current values ​​in the same type of compensation current data and a pre-divided current partition gradient; Dividing the gradient according to the target current matching corresponding to the compensation current threshold; Estimated risk state information is generated according to the compensation current distribution rate corresponding to the target current division gradient.

8. A phase error detection and prevention system for arc extinguishing devices compatible with arc extinguishing coil operation, applied to the arc extinguishing device according to claim 2, characterized in that: The three-phase lines of the busbar are all equipped with phase current transformers. The system includes: An information receiving module controls the front circuit breaker to close upon receiving short circuit fault information fed back from the feeder side of the power distribution system; The following steps are executed repeatedly until all phase switches are marked as filtered or the arc suppression switches are closed: A fault identification and classification module is configured to generate fault phase identification information based on phase current values ​​fed back by the phase current transformers obtained in real time; an identification adding module, configured to control the closing of the corresponding phase switch in the arc-extinguishing phase-splitting circuit breaker according to the fault phase identification information, and to add a filtered identification to the phase switch currently in the closed state; an information receiving module for receiving the phase selection current feedback information fed back by the current transformer 1 and generating phase selection judgment information carrying a correct identification mark or an incorrect identification mark according to the phase selection current feedback information; a fault identification and classification module, which controls the arc suppression switch to close if the phase selection judgment information carries a correct identification mark; a fault identification and classification module, which disconnects the phase switch currently in the closed state if the phase selection judgment information carries an identification error flag; The information receiving module is used to obtain the operating temperature value of the arc suppression coil and the current compensation current value fed back by the current transformer 2 in real time; The data matching module is used to match the corresponding target theoretical operating temperature value in the preset arc suppression coil theoretical temperature rise data according to the current compensation current value. The arc suppression coil theoretical temperature rise data is used to reflect the corresponding relationship between the theoretical compensation current value and the theoretical operating temperature value; A data calculation module is used to calculate and generate a current estimated temperature difference based on the current actual operating temperature value and the target theoretical operating temperature value; An information receiving module is used to obtain historical compensation current data and historical operating temperature data of the current arc suppression coil; A data calculation module is used to generate historical estimated temperature difference information based on historical compensation current data, historical operating temperature data, and arc suppression coil theoretical temperature rise data; A data calculation module is used to generate a compensation current threshold based on historical estimated temperature difference information, current estimated temperature difference and a preset upper temperature threshold; An information receiving module is used to obtain the same type of compensation current data at the same distribution voltage level as the current arc suppression device in the distribution network; The data matching module is used to generate estimated risk status information based on the same type of compensation current data and compensation current threshold.

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