Surge monitoring method and device for power distribution terminal and electronic equipment

Abstract

The invention provides a surge monitoring method and device for a power distribution terminal and electronic equipment, and relates to the technical field of power grids. According to the invention, when it is monitored that there is a sudden change signal in each phase analog parameter of the power distribution terminal, timing is carried out, secondary sudden change detection is carried out in a half-cycle set time period after a half cycle of the current frequency, and if no secondary sudden change signal is detected, it is determined that the power distribution terminal is subjected to surge interference; therefore, rapid and accurate distinguishing of the abrupt change signal detected by the power distribution terminal can be realized in one period, the problem of overcurrent maloperation caused by surge interference is solved, rapid response when a short-circuit fault occurs is ensured, and normal operation of a power grid is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of electric power grid, and in particular to a surge monitoring method, device and electronic equipment for a power distribution terminal. Background Art

[0002] The distribution terminal has the functions of line monitoring, fault location and fault isolation. During the normal operation of the power grid, when the distribution terminal detects a line short-circuit fault, the analog quantity collected by the distribution terminal changes suddenly, the distribution terminal overcurrent protection, and sends a trip command to the line switch to achieve fault isolation and short-circuit protection of the power grid line.

[0003] In thunderstorm weather, when the distribution terminal is operating normally on site, lightning strikes will interfere with the line, that is, surge interference. Under the influence of surge interference, the analog data collected by the distribution terminal will also change suddenly in a short period of time, and the effective value of the analog data will be greater than the current threshold value of the overcurrent protection of the distribution terminal, which will cause the overcurrent protection of the distribution terminal to malfunction, and issue a trip command to the line switch, causing power outages in the downstream area of ​​the switch, affecting the normal operation of the equipment in the downstream area of ​​the switch.

[0004] In order to avoid surge interference misoperation, the current method is to discard N sampling point data, that is, after detecting a sudden change signal, directly discard the N sampling point data. In the data sampling process, generally one cycle of data, that is, 128 sampling points, is collected for judgment and processing. If it is determined that there is a sudden change signal in this cycle, the N sampling points after this cycle are directly discarded, and then the analog data collected by the distribution terminal is re-detected.

[0005] However, when a sudden change in the analog quantity collected by the distribution terminal is detected, the sampling point processing method is directly abandoned, and the processing time is long, which is the time of 128+N sampling points, which is easy to exceed the prescribed time of 40ms for short-circuit protection. If the analog quantity suddenly changes into a downstream short-circuit fault, the action time exceeds the limit, which makes the equipment in the downstream area of ​​the distribution terminal have safety hazards.

[0006] Therefore, the current distribution terminal's processing method for sudden change signals has problems such as over-current false operation and excessive action duration, which affects the normal operation of the power grid. Summary of the invention

[0007] The present invention provides a surge monitoring method, device and electronic equipment for a distribution terminal, which can realize rapid differentiation of mutation signals detected by the distribution terminal, solve the problem of overcurrent malfunction caused by surge interference, and ensure rapid response when a short circuit fault occurs, thereby ensuring the normal operation of the power grid.

[0008] In the first aspect, the present invention provides a surge monitoring method for a distribution terminal, the method comprising: monitoring whether there is a mutation signal in each phase parameter of the distribution terminal; if a mutation signal is detected in each phase parameter, starting timing and recording the timing duration; within a set time period in which the timing duration is greater than a first threshold and less than or equal to a second threshold, re-detecting each phase parameter of the distribution terminal; the first threshold is half a cycle of the current frequency, and the second threshold is one cycle of the current frequency; if no secondary mutation signal is detected within the set time period, it is determined that the distribution terminal is subject to surge interference.

[0009] In a possible implementation, the method further includes: if a secondary mutation signal is detected within a set time period, determining that the mutation signal and the secondary mutation signal are normally applied analog signals.

[0010] In one possible implementation, if no secondary mutation signal is detected within a set time period, it is determined that the distribution terminal is subjected to surge interference, and further includes: generating a surge protection instruction, the surge protection instruction is used to instruct the distribution terminal subjected to surge interference to cut off power; based on the surge protection instruction, controlling the circuit breaker to disconnect, so as to realize surge protection of the circuit where the distribution terminal is located.

[0011] In a possible implementation, after controlling the circuit breaker to disconnect based on a surge protection instruction to implement surge protection for the circuit where the distribution terminal is located, it also includes: starting timing after the circuit breaker is disconnected to obtain the power outage duration; if the power outage duration reaches the reclosing duration, generating a reclosing instruction, and the reclosing instruction is used to instruct the circuit breaker to reclose; controlling the circuit breaker to close based on the reclosing instruction to implement reclosing of the distribution terminal.

[0012] In a possible implementation, if no secondary mutation signal is detected within a set time period, it is determined that the power distribution terminal is subjected to surge interference, and further includes: filtering the mutation signal to obtain filtered phase parameters; and storing the filtered phase parameters.

[0013] In the second aspect, an embodiment of the present invention provides a surge monitoring device for a distribution terminal, which includes: a communication module and a processing module, the communication module being used to monitor whether there is a mutation signal in each phase parameter of the distribution terminal; the processing module being used to start timing and record the timing duration if a mutation signal is detected in the parameters of each phase; within a set time period in which the timing duration is greater than a first threshold and less than or equal to a second threshold, re-detecting the parameters of each phase of the distribution terminal; the first threshold is half a cycle of the current frequency, and the second threshold is one cycle of the current frequency; if no secondary mutation signal is detected within the set time period, it is determined that the distribution terminal is subject to surge interference.

[0014] In a possible implementation, the processing module is further configured to determine that the mutation signal and the secondary mutation signal are normally applied analog signals if a secondary mutation signal is detected within a set time period.

[0015] In a possible implementation, the processing module is further used to generate a surge protection instruction, which is used to instruct the distribution terminal affected by surge interference to cut off power; based on the surge protection instruction, the circuit breaker is controlled to disconnect to achieve surge protection for the circuit where the distribution terminal is located.

[0016] In one possible implementation, the processing module is also used to start timing after the circuit breaker is disconnected to obtain the power outage duration; if the power outage duration reaches the reclosing duration, a reclosing instruction is generated, and the reclosing instruction is used to instruct the circuit breaker to reclose; the circuit breaker is controlled to close based on the reclosing instruction to achieve reclosing of the distribution terminal.

[0017] In a third aspect, an embodiment of the present invention provides an electronic device, comprising a memory and a processor, the memory storing a computer program, the processor being used to call and run the computer program stored in the memory to perform the steps of the method described in the first aspect and any possible implementation method of the first aspect.

[0018] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and wherein when the computer program is executed by a processor, the steps of the method described in the first aspect and any possible implementation method of the first aspect are implemented.

[0019] The present invention provides a surge monitoring method, device and electronic equipment for a distribution terminal. When the present invention detects that there is a mutation signal in each phase analog quantity parameter of the distribution terminal, timing is performed, and secondary mutation detection is performed within a half-cycle set time period after half a cycle of the current frequency. If no secondary mutation signal is detected, it is determined that the distribution terminal is subject to surge interference. In this way, the distribution terminal can detect mutation signals quickly and accurately within one cycle, which not only solves the problem of overcurrent malfunction caused by surge interference, but also ensures a rapid response when a short-circuit fault occurs, thereby ensuring the normal operation of the power grid. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 paying creative labor.

[0021] Figure 1It is a flow chart of a surge monitoring method for a power distribution terminal provided by an embodiment of the present invention;

[0022] Figure 2 It is a structural schematic diagram of a surge monitoring device for a power distribution terminal provided by an embodiment of the present invention;

[0023] Figure 3 It is a structural schematic diagram of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0024] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present invention.

[0025] In the description of the present invention, unless otherwise specified, " / " means "or", for example, A / B can mean A or B. "And / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, "at least one" and "plurality" refer to two or more. The words "first", "second", etc. do not limit the quantity and execution order, and the words "first", "second", etc. do not limit them to be different.

[0026] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a concrete way for easy understanding.

[0027] In addition, the terms "including" and "having" and any variations thereof mentioned in the description of this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or modules is not limited to the listed steps or modules, but may optionally include other steps or modules that are not listed, or may optionally include other steps or modules that are inherent to these processes, methods, products or devices.

[0028] In order to make the purpose, technical solutions and advantages of the present invention more clear, the following will be described through specific embodiments in conjunction with the accompanying drawings of the present invention.

[0029] As described in the background technology, assuming that the normal B-phase current collected by the distribution terminal is 0.95A, and the B-phase current of the distribution terminal is 2.15A after the sudden disturbance, and the overcurrent protection setting is set to 1.2A, then this signal mutation is determined to be a surge disturbance, resulting in the overcurrent protection action. However, since this signal mutation is a surge disturbance and the duration is short, the sudden disturbance to the B-phase current sampling point only lasts for 5-10 sampling points, resulting in the effective value of the B-phase current of 2.15A in one cycle being greater than the overcurrent protection setting of 1.2A, and the overcurrent protection malfunctions.

[0030] Due to the transient nature of surge interference (several hundred us), there is a problem of overcurrent false operation in the detection method of surge interference at the distribution terminal. The distribution terminal has been optimized for software. When the grid frequency is 50HZ, it takes 20ms for the distribution terminal to collect one cycle of data. The collected data is 128 sampling points. The number of sampling points caused by surge interference is generally 5-10. When the analog quantity mutates, the software settings will discard sampling points greater than the set N (settable) and then recalculate the analog quantity data. In this way, the distribution terminal will not have the above overcurrent protection false operation problem.

[0031] The power industry standard for distribution terminals requires that the time from the application of analog quantity to the protection output cannot exceed 40ms. When the analog quantity changes suddenly, more than N sampling points are discarded according to the software settings, and the analog quantity data is recalculated, which will cause the analog quantity calculation of the distribution terminal to be delayed by N sampling points (taking 50HZ sampling as an example, the time of 1 sampling point is 20ms / 128 sampling points = 156.25us). The protection action output time is one cycle + the length of N sampling points (normally 36-38ms), which has a probability of exceeding the 40ms required by the specification and does not meet the prescribed time limit for surge protection.

[0032] That is to say, after a sudden change in the analog quantity occurs at the distribution terminal, the set number of interference sampling points is filtered according to the set value of the number of interference sampling points, and they are not involved in the analog quantity calculation. Then, the data of one cycle is collected again to calculate the effective value. This will not cause false operation of the overcurrent protection. However, it is obviously inappropriate to filter the sampling points as long as the analog quantity suddenly changes, which may easily cause the distribution terminal protection tripping time to exceed the 40ms required by the specification.

[0033] In order to solve the above technical problems, an embodiment of the present invention provides a surge monitoring method for a power distribution terminal, which includes steps S101-S104.

[0034] S101. Monitor each phase parameter of the power distribution terminal to see if there is a mutation signal.

[0035] S102: If a sudden change signal is detected in each phase parameter, start timing and record the timing duration.

[0036] S103: within a set time period in which the timing duration is greater than the first threshold and less than or equal to the second threshold, re-detect each phase parameter of the power distribution terminal.

[0037] In the embodiment of the present application, the first threshold is half a cycle of the current frequency, and the second threshold is one cycle of the current frequency.

[0038] S104: If no secondary mutation signal is detected within the set time period, it is determined that the power distribution terminal is subject to surge interference.

[0039] The present invention provides a surge monitoring method for a distribution terminal. When a mutation signal is detected in each phase analog parameter of the distribution terminal, timing is performed, and a secondary mutation detection is performed within a half-cycle set time period after half a cycle of the current frequency. If no secondary mutation signal is detected, it is determined that the distribution terminal is subject to surge interference. In this way, the distribution terminal can detect mutation signals quickly and accurately within one cycle, which not only solves the problem of overcurrent malfunction caused by surge interference, but also ensures a rapid response when a short-circuit fault occurs, thereby ensuring the normal operation of the power grid.

[0040] Optionally, the surge monitoring method for a power distribution terminal provided in an embodiment of the present invention further includes step S106.

[0041] S106: If a secondary mutation signal is detected within a set period of time, the mutation signal and the secondary mutation signal are determined to be normal test signals.

[0042] Among them, the normal test signal is a sudden change signal that occurs when a short circuit fault occurs in the area where the distribution terminal is located.

[0043] In this way, the embodiment of the present invention can quickly distinguish normal test signals from surge interference signals, thereby improving the reliability of surge monitoring of the power distribution terminal.

[0044] Optionally, the surge monitoring method for a power distribution terminal provided in an embodiment of the present invention further includes steps S107-S108 after step S104.

[0045] S107, filtering the mutation signal to obtain filtered parameters of each phase.

[0046] S108. Store the filtered parameters of each phase.

[0047] In this way, the embodiment of the present invention can filter the detection parameters when determining that the power distribution terminal is subject to surge interference, thereby achieving rapid and reliable monitoring of surge interference at the power distribution terminal.

[0048] Optionally, the surge monitoring method for a power distribution terminal provided in an embodiment of the present invention further includes steps S201 - S202 after step S104 .

[0049] S201: Generate a surge protection instruction.

[0050] In some embodiments, the surge protection instruction is used to instruct the power distribution terminal affected by the surge to cut off power.

[0051] S202. Based on the surge protection instruction, the circuit breaker is controlled to be disconnected to implement surge protection of the circuit where the power distribution terminal is located.

[0052] In this way, after determining that the distribution terminal is subject to surge interference, surge protection is performed on the circuit where the distribution terminal is located to avoid the impact of surge interference on the equipment and ensure the safety of the equipment in the area where the distribution terminal is located.

[0053] Optionally, the surge monitoring method for a power distribution terminal provided in an embodiment of the present invention further includes steps S203-S205 after step S202.

[0054] S203: After the circuit breaker is disconnected, start timing to obtain the power outage duration.

[0055] S204: If the power outage duration reaches the reclosing duration, a reclosing instruction is generated.

[0056] In some embodiments, a reclose command is used to instruct the circuit breaker to reclose.

[0057] S205. Control the circuit breaker to close based on the reclosing instruction to achieve reclosing of the distribution terminal.

[0058] In this way, the embodiment of the present invention can reclose the circuit breaker after opening the circuit breaker to ensure the normal and reliable operation of the power grid.

[0059] It should be understood that the order of execution of the steps in the above embodiment does not necessarily mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0060] The following is an embodiment of the device of the present invention. For details not described in detail therein, reference may be made to the corresponding method embodiment described above.

[0061] Figure 2 The schematic diagram of the structure of a surge monitoring device for a power distribution terminal provided by an embodiment of the present invention is shown. The surge monitoring device 300 includes a communication module 301 and a processing module 302 .

[0062] The communication module 301 is used to monitor whether there is a sudden change signal in each phase parameter of the power distribution terminal.

[0063] The processing module 302 is used to start timing and record the timing duration if a sudden change signal is detected in the parameters of each phase; within a set time period in which the timing duration is greater than a first threshold and less than or equal to a second threshold, re-detect the parameters of each phase of the distribution terminal; the first threshold is half a cycle of the current frequency, and the second threshold is one cycle of the current frequency; if no secondary sudden change signal is detected within the set time period, it is determined that the distribution terminal is subject to surge interference.

[0064] Figure 3 Schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. Figure 3 As shown, the electronic device 400 includes: a processor 401, a memory 402, and a computer program 403 stored in the memory 402 and executable on the processor 401. When the processor 401 executes the computer program 403, the steps in the above-mentioned method embodiments are implemented, for example Figure 1 Alternatively, when the processor 401 executes the computer program 403, the functions of each module / unit in the above-mentioned device embodiments are realized, for example, Figure 2 The functions of the communication module 301 and the processing module 302 are shown.

[0065] Exemplarily, the computer program 403 may be divided into one or more modules / units, which are stored in the memory 402 and executed by the processor 401 to implement the present invention. The one or more modules / units may be a series of computer program instruction segments that can implement specific functions, and the instruction segments are used to describe the execution process of the computer program 403 in the electronic device 400. For example, the computer program 403 may be divided into Figure 2 The communication module 301 and the processing module 302 are shown.

[0066] The processor 401 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0067] The memory 402 may be an internal storage unit of the electronic device 400, such as a hard disk or memory of the electronic device 400. The memory 402 may also be an external storage device of the electronic device 400, such as a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), etc. equipped on the electronic device 400. Further, the memory 402 may also include both an internal storage unit of the electronic device 400 and an external storage device. The memory 402 is used to store the computer program and other programs and data required by the terminal. The memory 402 may also be used to temporarily store data that has been output or is to be output.

[0068] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A surge monitoring method for a power distribution terminal, characterized in that: include: Monitor the parameters of each phase of the power distribution terminal to see if there are any mutation signals; If a sudden change signal is detected in the parameters of each phase, the timing is started and the timing duration is recorded; Within a set period of time in which the timing duration is greater than a first threshold and less than or equal to a second threshold, the parameters of each phase of the power distribution terminal are re-detected; the first threshold is half a cycle of the current frequency, and the second threshold is one cycle of the current frequency; If no secondary mutation signal is detected within the set time period, it is determined that the power distribution terminal is subject to surge interference.

2. The surge monitoring method for a power distribution terminal according to claim 1, characterized in that: The method further comprises: If a secondary mutation signal is detected within a set period of time, it is determined that the mutation signal and the secondary mutation signal are normally applied analog signals.

3. The surge monitoring method for a power distribution terminal according to claim 1, characterized in that: If no secondary mutation signal is detected within the set time period, it is determined that the power distribution terminal is subjected to surge interference, and further includes: Generate a surge protection instruction, wherein the surge protection instruction is used to instruct the power distribution terminal affected by the surge to cut off power; Based on the surge protection instruction, the circuit breaker is controlled to disconnect to achieve surge protection for the circuit where the distribution terminal is located.

4. The method for surge monitoring of a power distribution terminal according to claim 3, characterized in that: After the circuit breaker is controlled to be disconnected based on the surge protection instruction to implement surge protection of the circuit where the power distribution terminal is located, the method further includes: After the circuit breaker is disconnected, start timing to obtain the power outage duration; If the power-off duration reaches the reclosing duration, a reclosing instruction is generated, wherein the reclosing instruction is used to instruct the circuit breaker to close again; The circuit breaker is controlled to close based on the reclosing instruction to achieve reclosing of the distribution terminal.

5. The surge monitoring method for a power distribution terminal according to claim 2, characterized in that: If no secondary mutation signal is detected within the set time period, it is determined that the power distribution terminal is subjected to surge interference, and further includes: Filtering the mutation signal to obtain filtered parameters of each phase; The filtered parameters of each phase are stored.

6. A surge monitoring device for a power distribution terminal, characterized in that: include: A communication module is used to monitor whether there is a mutation signal in each phase parameter of the power distribution terminal; A processing module, configured to start timing and record the timing duration if a mutation signal is detected in the parameters of each phase; and re-detect the parameters of each phase of the power distribution terminal within a set period in which the timing duration is greater than a first threshold and less than or equal to a second threshold; the first threshold is half a cycle of the current frequency, and the second threshold is one cycle of the current frequency; If no secondary mutation signal is detected within the set time period, it is determined that the power distribution terminal is subject to surge interference.

7. The surge monitoring device for a power distribution terminal according to claim 6, characterized in that: The processing module is further configured to determine that the mutation signal and the secondary mutation signal are normally applied analog signals if a secondary mutation signal is detected within a set time period.

8. The surge monitoring device for a power distribution terminal according to claim 6, characterized in that: The processing module is also used to generate a surge protection instruction, which is used to instruct the distribution terminal affected by surge interference to cut off power; based on the surge protection instruction, the circuit breaker is controlled to disconnect to achieve surge protection for the circuit where the distribution terminal is located.

9. The surge monitoring device for a power distribution terminal according to claim 8, characterized in that: The processing module is also used to start timing after the circuit breaker is disconnected to obtain the power outage duration; if the power outage duration reaches the reclosing duration, a reclosing instruction is generated, and the reclosing instruction is used to instruct the circuit breaker to reclose; based on the reclosing instruction, the circuit breaker is controlled to close to achieve reclosing of the distribution terminal.

10. An electronic device, characterized in that: The electronic device comprises a memory and a processor, the memory stores a computer program, and the processor is used to call and run the computer program stored in the memory to execute the steps of the method according to any one of claims 1 to 5.

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