Power distribution network fast loop closing and opening control method and device based on 5G communication

Abstract

The application provides a power distribution network fast loop closing and opening control method and device based on 5G communication, relates to the technical field of data processing, and comprises the following steps: a master station issues a preset instruction to a tie switch terminal and a sectionalizing switch terminal, issues a loop closing and opening execution instruction to the tie switch terminal after a preset success signal is returned, and executes a loop closing action after the loop closing and opening execution instruction is received by the tie switch terminal, and sends a loop closing action signal to the sectionalizing switch terminal in a point-to-point manner through 5G wireless communication; the sectionalizing switch terminal executes a loop opening action according to a matching relationship in the stored preset instruction after the loop closing action signal is received, and returns a loop opening action signal to the tie switch terminal; and the tie switch terminal judges the execution result of the current loop closing and opening operation according to the loop opening action signal, a line current signal and a switch position signal of the local end. The application solves the problem that the loop opening action trigger of the sectionalizing switch terminal depends on the signal transfer of the master station and cannot be linked to respond after the loop closing action of the tie switch occurs.

Description

Technical Field

[0001] This application relates to the field of data processing technology, and in particular to a method and apparatus for rapid loop closure and reclosure control of power distribution networks based on 5G communication. Background Technology

[0002] The closing and opening loop operation of the distribution network is an operation method that transfers line loads without interrupting power supply to users by controlling the opening and closing actions of tie switches and sectionalizing switches. With the improvement of the automation level of the distribution network, intelligent pole-mounted switch terminals have been widely deployed on 10kV overhead lines. The master station coordinates the opening and closing actions of the tie switch terminals and sectionalizing switch terminals by issuing control commands to complete the closing and opening loop operation.

[0003] In the above control method, after the tie switch terminal performs a loop-closing action, it needs to report the action signal to the master station, which then forwards the loop-breaking command to the sectional switch terminal, allowing the sectional switch terminal to perform the loop-breaking action. The loop-breaking action of the sectional switch terminal depends on the signal relay of the master station. The processing and forwarding process of the master station prevents the sectional switch terminal from responding in a coordinated manner after the loop-closing action occurs.

[0004] Therefore, how to enable the sectionalizing switch terminal to perform the loop-breaking action in conjunction with the closing action of the tie switch has become an urgent problem to be solved. Summary of the Invention

[0005] This application provides a method and device for fast loop closing and opening control of distribution networks based on 5G communication, in order to solve the problem that the loop opening action of the sectionalizing switch terminal depends on the relay of the master station signal and cannot be linked to respond after the loop closing action of the tie switch occurs.

[0006] The first aspect of this application provides a fast loop-closing control method for a distribution network based on 5G communication, comprising: a master station sending a preset command to a tie switch terminal and a sectional switch terminal; and after the tie switch terminal and the sectional switch terminal return a preset success signal, the master station sending a loop-closing execution command to the tie switch terminal. After receiving the closing and unclosing loop execution command, the communication switch terminal performs the closing loop action and sends the closing loop action signal to the segment switch terminal in a point-to-point manner via 5G wireless communication. After receiving the loop closing action signal, the segmented switch terminal performs a loop breaking action according to the pairing relationship in the stored preset instructions, and returns a loop breaking action signal to the tie switch terminal. The interconnection switch terminal determines the execution result of this loop closing / closing operation based on the loop breaking action signal, the local line current signal, and the local switch position signal.

[0007] Optionally, in one possible implementation of the first aspect, the master station sends a preset command to the liaison switch terminal and the sectionalizing switch terminal. After the liaison switch terminal and the sectionalizing switch terminal return a preset success signal, the master station sends a loop-opening / closing execution command to the liaison switch terminal, including: The main station collects the voltage phase angles on both sides of the interconnection switch terminal, calculates the phase angle difference between the two sides based on the voltage phase angles on both sides of the interconnection switch terminal, and obtains the current phase angle difference value. The target unlooping segmented switch terminal is determined from multiple segmented switch terminals on the feeder based on the current phase angle difference. The identifier of the target loop-breaking segment switch terminal and the identifier of the communication switch terminal are combined to generate a preset command, and the preset command is sent to the communication switch terminal and the target loop-breaking segment switch terminal. After both the communication switch terminal and the target unlooping segment switch terminal return a preset success signal, the master station sends a closing and unlooping execution command to the communication switch terminal.

[0008] Optionally, in one possible implementation of the first aspect, determining the target unlooping sectionalizing switch terminal from a plurality of sectionalizing switch terminals on the feeder based on the current phase angle difference includes: In response to the current phase angle difference exceeding the first phase angle difference threshold pre-configured in the master station, the first sectionalizing switch terminal located at the substation side of the feeder is identified as the target loop-breaking sectionalizing switch terminal. In response to the current phase angle difference not exceeding the first phase angle difference threshold and exceeding the second phase angle difference threshold pre-configured in the master station, the intermediate sectionalizing switch terminal located on the feeder between the first sectionalizing switch terminal and the connecting switch terminal side is determined as the target loop-breaking sectionalizing switch terminal; In response to the current phase angle difference not exceeding the second phase angle difference threshold, the end segment switch terminal located on the tie switch terminal side of the feeder is identified as the target loop-breaking segment switch terminal.

[0009] Optionally, in one possible implementation of the first aspect, the step of combining the identifier of the target loop-breaking segment switch terminal with the identifier of the tie switch terminal to generate a preset instruction includes: Retrieve the location identifier of the target unloop segment switch terminal and the location identifier of the interconnection switch terminal; Based on the loop impedance between the target loop-breaking segment switch terminal and the tie switch terminal and the current phase angle difference, calculate the phase angle difference safety threshold corresponding to the target loop-breaking segment switch terminal; The communication delay is measured through the 5G wireless communication link between the main station and the communication switch terminal, and the transmission lag time is calculated based on the communication delay. The preset instruction is generated by combining the location identifier of the target loop-breaking segment switch terminal, the location identifier of the communication switch terminal, the phase angle difference safety threshold, and the transmission lag time.

[0010] Optionally, in one possible implementation of the first aspect, after receiving the loop closure execution command, the communication switch terminal performs a loop closure action and sends a loop closure action signal to the segment switch terminal in a point-to-point manner via 5G wireless communication, including: After receiving the closing and closing loop execution command, the interconnecting switch terminal reads the phase angle difference safety threshold in the preset command, and collects the current voltage phase angle on both sides of the interconnecting switch terminal to calculate the real-time phase angle difference value. Based on the comparison between the real-time phase angle difference and the phase angle difference safety threshold, in response to the real-time phase angle difference not exceeding the phase angle difference safety threshold, the interconnection switch terminal performs a loop closing action; In response to the real-time phase angle difference exceeding the phase angle difference safety threshold, a phase angle difference over-limit signal is reported to the master station. After the master station sends a compensation completion signal containing the phase angle difference after voltage regulation, the contact switch terminal performs the loop closing action. After the loop closing action is completed, the communication switch terminal reads the transmission lag time in the preset instruction, performs lag compensation on the transmission time of the loop closing action signal according to the transmission lag time, and sends the loop closing action signal to the target de-loop segment switch terminal in a point-to-point manner via 5G wireless communication.

[0011] Optionally, in one possible implementation of the first aspect, in response to the real-time phase angle difference exceeding the phase angle difference safety threshold, reporting a phase angle difference over-limit signal to the master station, and after the master station sends a compensation completion signal containing the phase angle difference after voltage regulation, the tie switch terminal then performs a loop-closing operation, including: The communication switch terminal reports the phase angle difference exceeding the limit signal to the master station; The master station calculates the required compensation amount based on the real-time phase angle difference and the phase angle difference safety threshold, and issues a voltage regulation command to the voltage regulation equipment on the substation side based on the required compensation amount; After the voltage regulation equipment on the substation side completes the voltage regulation, the master station re-collects the voltage phase angles on both sides of the tie switch terminal, calculates the phase angle difference after voltage regulation, confirms that the phase angle difference after voltage regulation does not exceed the phase angle difference safety threshold, incorporates the phase angle difference after voltage regulation into the compensation completion signal, and sends the compensation completion signal to the tie switch terminal. After receiving the compensation completion signal containing the phase angle difference after voltage adjustment, the contact switch terminal performs a loop closing operation.

[0012] Optionally, in one possible implementation of the first aspect, after the loop-closing operation is completed, the communication switch terminal reads the transmission lag duration in the preset instruction, performs lag compensation on the transmission time of the loop-closing operation signal according to the transmission lag duration, and sends the loop-closing operation signal to the target de-looping segment switch terminal in a point-to-point manner via 5G wireless communication, including: The communication switch terminal monitors the local switch position signal. In response to the local switch position signal changing from open to closed, it confirms that the loop closing action is completed and records the time when the local switch position signal changes from open to closed as the loop closing completion time. Read the transmission lag time from the preset instruction, and wait for a delay based on the loop completion time; After the delay period ends, the communication switch terminal sends a loop closing action signal to the target loop unblocking segment switch terminal via 5G wireless communication in a point-to-point manner.

[0013] Optionally, in one possible implementation of the first aspect, after receiving the loop-closing action signal, the segmented switch terminal performs a loop-breaking action according to the pairing relationship in the stored preset instructions, and returns a loop-breaking action signal to the tie switch terminal, including: The segmented switch terminal determines the corresponding target unlooping segmented switch terminal according to the pairing relationship in the preset instruction, and performs the unlooping action after receiving the loop closing action signal; After the loop-breaking action is completed, the time when the switch position signal of the target loop-breaking segment switch terminal changes from closed to open is used as the reference. The loop-breaking completion time is recorded, and the loop-breaking action signal is returned to the connecting switch terminal.

[0014] Optionally, in one possible implementation of the first aspect, the tie switch terminal determines the execution result of the current loop closing / closing operation based on the loop breaking action signal combined with the local line current signal and the local switch position signal, including: The interconnection switch terminal receives the loop-breaking action signal returned by the target loop-breaking segment switch terminal, extracts the position identifier and loop-breaking completion time of the target loop-breaking segment switch terminal from the loop-breaking action signal, and collects the local line current signal and the local switch position signal, and records the time when the local switch position signal changes from open to closed as the loop-closing completion time. The time difference between loop merging and loop unmerging is calculated based on the loop merging completion time and the loop unmerging completion time. The time difference between loop merging and loop unmerging is then compared with a preset synchronization time window pre-configured in the master station to obtain the execution result of this loop merging and loop unmerging operation.

[0015] Optionally, in one possible implementation of the first aspect, the step of calculating the loop merging / unmerging time difference based on the loop merging completion time and the loop unmerging completion time, and comparing the loop merging / unmerging time difference with a preset synchronization time window pre-configured in the master station to obtain the execution result of this loop merging / unmerging operation includes: The location identifier of the target loop-breaking section switch terminal is compared with the location identifier of the target loop-breaking section switch terminal in the preset instruction. Combined with the local line current signal, the local switch position signal and the loop-breaking time difference, the verification results are determined. If all verification results are passed, the loop merging and unmerging operation is deemed to have been successfully executed, and a successful loop merging and unmerging signal is reported to the master station.

[0016] Optionally, in one possible implementation of the first aspect, the response that all verification results pass, determining that the current ring merging and unmerging operation has been successfully executed, and reporting a ring merging and unmerging success signal to the master station, includes: In response to the following reasons: the local line current signal does not change from zero to positive; the location identifier of the target loop-breaking section switch terminal is inconsistent with the location identifier of the target loop-breaking section switch terminal in the preset instruction; the loop-closing time difference exceeds the preset synchronization time window; the tie switch terminal receives a loop-breaking failure signal returned by the target loop-breaking section switch terminal; or the local line current signal reaches the backup protection setting value pre-configured in the tie switch terminal, the loop-closing operation is determined to have failed, and a loop-closing failure signal is reported to the master station.

[0017] Optionally, in one possible implementation of the first aspect, it also includes: If the liaison switch terminal does not receive the loop-breaking action signal returned by the target loop-breaking section switch terminal within a preset time window configured in the liaison switch terminal, the liaison switch terminal performs a tripping action and blocks the closing, and reports a communication timeout failure signal on the liaison switch side to the master station. In response to the liaison switch terminal receiving the loop-breaking failure signal returned by the target loop-breaking section switch terminal, the liaison switch terminal performs a tripping action and blocks the closing action, and reports the section switch loop-breaking failure signal to the master station. In response to the local line current signal reaching the backup protection setting pre-configured in the tie switch terminal, the tie switch terminal triggers protection tripping and operates before the station switch, and reports a backup protection operation failure signal to the master station.

[0018] A second aspect of this application provides a fast loop-closing and loop-breaking device for a distribution network based on 5G communication, comprising: a preset module, used by the master station to send preset instructions to the tie switch terminal and the sectional switch terminal, and after the tie switch terminal and the sectional switch terminal return preset success signals, the master station sends a loop-closing and loop-breaking execution instruction to the tie switch terminal; The loop closing module is used to execute the loop closing action after the communication switch terminal receives the loop closing and unclosing execution command, and to send the loop closing action signal to the segment switch terminal in a point-to-point manner via 5G wireless communication. The loop-breaking module is used to execute a loop-breaking action according to the pairing relationship in the stored preset instructions after the segmented switch terminal receives the loop-closing action signal, and return a loop-breaking action signal to the interconnection switch terminal. The criterion module is used by the interconnection switch terminal to determine the execution result of the current loop closing / closing operation based on the loop closing action signal combined with the local line current signal and the local switch position signal.

[0019] The fast loop-closing and loop-breaking control method and device for power distribution networks based on 5G communication provided in this application have the following advantages: 1. In the pre-setting stage of loop closing and disclosing, the master station calculates the phase angle difference by collecting the voltage phase angles on both sides of the interconnection switch terminal, dynamically determines the target disclosing segment switch terminal based on the phase angle difference, and incorporates the phase angle difference safety threshold and communication delay compensation parameters into the pre-setting command. Since the selection of the target disclosing segment switch terminal is directly related to the current operating conditions, it avoids the problem of excessive loop closing inrush current caused by changes in operating conditions under the fixed pairing method; 2. After the liaison switch terminal completes the loop closing action, this application directly sends the loop closing action signal to the target unlooping segment switch terminal via 5G wireless communication in a point-to-point manner, triggering its linkage to execute the unlooping action. Since the loop closing action signal does not need to be processed and forwarded by the master station, the processing delay introduced by the master station relay link is eliminated, enabling the segment switch terminal to directly link and respond after the liaison switch loop closing action occurs; 3. This application compensates for the lag in the transmission time of the loop closing action signal to offset the impact of 5G communication link transmission delay on the timing coordination of loop closing and disclosing. After receiving the loop disclosing action signal, the contact switch terminal performs multi-dimensional verification by combining the local line current signal, the local switch position signal and the time difference between loop closing and disclosing. This allows the judgment of the operation result to cover multiple failure scenarios such as communication anomalies, action refusal to operate and timing deviations, thereby improving the comprehensiveness and accuracy of the judgment of the loop closing and disclosing operation result. Attached Figure Description

[0020] Figure 1 This is a flowchart illustrating the fast loop-closing control method for power distribution networks based on 5G communication provided in this application embodiment; Figure 2This is a schematic diagram of the feeder topology and phase angle differential scenario selection logic of the fast closing and opening loop control method for distribution networks based on 5G communication provided in the embodiments of this application; Figure 3 This is a timing diagram of a fast loop-closing and loop-breaking device for a power distribution network based on 5G communication, provided in an embodiment of this application. Figure 4 This is a schematic diagram of the hardware structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0022] The technical solutions of this application will be described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0023] See Figure 1 This is a flowchart illustrating the fast loop-closing control method for distribution networks based on 5G communication provided in this application embodiment. Figure 1 The execution entity of the method shown can be a software and / or hardware device. The execution entity of this application can include, but is not limited to, at least one of the following: user equipment, network equipment, etc. User equipment can include, but is not limited to, computers, smartphones, personal digital assistants (PDAs), and the aforementioned electronic devices. Network equipment can include, but is not limited to, a single network server, a server group consisting of multiple network servers, or a cloud based on cloud computing consisting of a large number of computers or network servers. Cloud computing is a type of distributed computing, consisting of a super virtual computer composed of a group of loosely coupled computers. This embodiment does not impose any limitations on this.

[0024] The fast loop-closing and loop-breaking control method for distribution networks based on 5G communication provided in this application includes steps S1 to S4, as detailed below: Step S1: The master station sends a preset command to the tie switch terminal and the sectional switch terminal. After the tie switch terminal and the sectional switch terminal return a preset success signal, the master station sends a loop-opening / closing execution command to the tie switch terminal.

[0025] The preset command is configuration information pre-sent by the master station to the tie switch terminal and the sectional switch terminal before the closed-loop operation is executed. It includes the pairing relationship and execution parameters for this closed-loop operation. The preset success signal is an acknowledgment signal returned by the tie switch terminal and the sectional switch terminal to the master station after completing the local storage of the preset command. The closed-loop execution command is the operation start signal sent by the master station to the tie switch terminal after confirming that the presets at both ends have been completed.

[0026] After receiving the preset command, the tie switch terminal and the sectional switch terminal store the pairing relationship and execution parameters locally, and directly call them when they receive the loop closure / reopening execution command or the loop closure action signal. The master station can only issue the loop closure / reopening execution command after receiving preset success signals from both ends; if either terminal does not return a preset success signal, the master station will not issue the loop closure / reopening execution command to avoid starting the loop closure / reopening operation before the configuration is complete.

[0027] Understandably, after the parameter storage is completed in the pre-setting stage, there is no need for additional parameter interaction with the main station in the execution stage, which lays the foundation for the rapid linkage execution of subsequent steps S2 and S3.

[0028] It should be noted that in conventional loop closing and opening operations, the master station fixedly designates the sectionalizing switch terminals to participate in the operation, without considering the phase angle difference between the two sides of the tie switch under the current operating conditions. For example, if the phase angle difference between the two sides is large, and the sectionalizing switch terminal with the smaller loop impedance is still selected to perform the loop opening action, the inrush current generated at the moment of loop closing will exceed the allowable range of the line. Traditional methods cannot adjust the selection of the loop opening target according to changes in operating conditions. To solve the above problem, in some embodiments, step S1 includes steps S11 to S14: Step S11: The main station collects the voltage phase angles on both sides of the tie switch terminal, calculates the phase angle difference between the two sides based on the voltage phase angles on both sides of the tie switch terminal, and obtains the current phase angle difference value.

[0029] The voltage phase angles on both sides of the tie switch terminal are the real-time voltage phase angle values ​​between the substation side and the feeder on the opposite side of the tie switch terminal, which are collected by the master station through the communication link with the tie switch terminal. The current phase angle difference is the absolute value of the difference between the voltage phase angles on both sides of the tie switch terminal, reflecting the phase deviation of the power supply on both sides under the current operating conditions.

[0030] The master station sends a voltage phase angle acquisition request to the tie switch terminal. The tie switch terminal reports the real-time voltage phase angles on both sides of its own end to the master station. The master station calculates the difference between the voltage phase angles on both sides and takes the absolute value to obtain the current phase angle difference, which serves as the input basis for determining the target unlooping segment switch terminal in step S12.

[0031] The current phase angle difference directly reflects the magnitude of the inrush current that may be generated at the moment of loop closure. It is a quantitative basis for determining which loop impedance segmented switch terminal should be selected under the current operating conditions, and provides a data basis for the scenario-specific selection in step S12.

[0032] Step S12: Determine the target unlooping sectionalizing switch terminal from multiple sectionalizing switch terminals on the feeder based on the current phase angle difference.

[0033] The target unblocking sectionalizing switch terminal is the sectionalizing switch terminal that performs the unblocking action in this unblocking operation, and is determined from multiple sectionalizing switch terminals already deployed on the feeder. The first phase angle difference threshold and the second phase angle difference threshold are two phase angle difference judgment values ​​pre-configured in the master station, with the first phase angle difference threshold being greater than the second phase angle difference threshold. The specific values ​​of the first and second phase angle difference thresholds can be determined by those skilled in the art as follows: using the line rated voltage as a reference, multiply the maximum allowable inrush current of the line by the loop impedance between the first sectionalizing switch terminal and the tie switch terminal to obtain the maximum allowable voltage difference between the two ends; then divide the maximum allowable voltage difference between the two ends by the line rated voltage, take the arcsine value, and obtain the corresponding upper limit of the phase angle difference, which is the first phase angle difference threshold. The determination method for the second phase angle difference threshold is the same as for the first phase angle difference threshold; replace the loop impedance in the calculation with the loop impedance between the end sectionalizing switch terminal and the tie switch terminal to obtain the upper limit of the phase angle difference corresponding to the end sectionalizing switch terminal, which is the second phase angle difference threshold. Since the loop impedance between the end sectionalizing switch terminal and the tie switch terminal is less than the loop impedance between the first sectionalizing switch terminal and the tie switch terminal, the allowable voltage difference corresponding to the end sectionalizing switch terminal is smaller under the same maximum inrush current conditions. Therefore, the second phase angle difference threshold is lower than the first phase angle difference threshold.

[0034] It should be noted that the loop impedance between the sectionalizing switch terminal and the tie switch terminal at different locations on the feeder is different, with the loop impedance being larger the closer the location is to the substation side. For example, in a high phase angle difference scenario, if the end sectionalizing switch terminal with a smaller loop impedance is selected, the inrush current will exceed the allowable range; in a low phase angle difference scenario, if the first sectionalizing switch terminal with the largest loop impedance is selected, the loop breaking range will be unnecessarily expanded. The master station compares the current phase angle difference value with the first phase angle difference threshold and the second phase angle difference threshold, and selects the sectionalizing switch terminal with the corresponding loop impedance for different scenarios, so that the selection of the target loop breaking sectionalizing switch terminal is directly related to the current operating conditions.

[0035] Reference Figure 2 This is a schematic diagram for selecting the logic of the feeder topology and phase angle differential scenario. Figure 2The top shows the positional relationship of the switches on the feeder line, arranged sequentially from the substation side to the tie switch terminal side: first section switch terminal CB1, intermediate section switch terminal CB2, end section switch terminal CB3, and tie switch terminal TL. Figure 2 As can be seen above, the closer the sectionalizing switch terminal is to the substation side, the greater the loop impedance between it and the tie switch terminal. The three satisfy Z1>Z2>Z3, and the magnitude of the loop impedance directly corresponds to the position of the sectionalizing switch terminal on the feeder. Figure 2 The diagram below shows the correspondence between the current phase angle difference δ and the selected target loop-breaking segment switch terminal. Using the second phase angle difference threshold δ2 and the first phase angle difference threshold δ1 as the dividing points, the current phase angle difference range is divided into three scenarios: low, medium, and high. For each scenario, CB3, CB2, and CB1 are selected as the target loop-breaking segment switch terminals, respectively. Figure 2 As can be seen below, the larger the phase angle difference, the larger the loop impedance should be selected for the segmented switch terminal. The reason is that the larger the loop impedance, the smaller the inrush current generated when closing the loop. Thus, the inrush current when closing the loop can be controlled within the allowable range under different phase angle difference conditions, while avoiding unnecessary expansion of the loop breaking range in low phase angle difference scenarios.

[0036] In some embodiments, step S12 includes steps S121 to S123: Step S121: In response to the current phase angle difference exceeding the first phase angle difference threshold, the first sectionalizing switch terminal located on the substation side of the feeder is identified as the target loop-breaking sectionalizing switch terminal.

[0037] The first sectionalizing switch terminal is the sectionalizing switch terminal located on the substation side of the feeder, and its loop impedance with the tie switch terminal is the largest among the multiple sectionalizing switch terminals on the feeder.

[0038] The main station compares the current phase angle difference with the first phase angle difference threshold. If the current phase angle difference exceeds the first phase angle difference threshold, it confirms that the current operating condition belongs to the high phase angle difference scenario and determines the first segmented switch terminal as the target loop-breaking segmented switch terminal.

[0039] Understandably, the demand for inrush current suppression is strongest in high phase angle difference scenarios. Selecting the first segment switch terminal with the largest loop impedance can limit the closed-loop inrush current to within the allowable range under conditions of large phase angle difference.

[0040] Step S122: In response to the current phase angle difference not exceeding the first phase angle difference threshold and exceeding the second phase angle difference threshold, the intermediate sectionalizing switch terminal located between the first sectionalizing switch terminal and the tie switch terminal on the feeder is determined as the target unlooping sectionalizing switch terminal.

[0041] The intermediate sectionalizing switch terminal is a sectionalizing switch terminal located on the feeder between the first sectionalizing switch terminal and the tie switch terminal. The loop impedance between the intermediate sectionalizing switch terminal and the tie switch terminal is between the loop impedances corresponding to the first sectionalizing switch terminal and the end sectionalizing switch terminal.

[0042] The master station responds when the current phase angle difference does not exceed the first phase angle difference threshold but exceeds the second phase angle difference threshold, confirms that the current operating condition belongs to the medium phase angle difference scenario, and determines the intermediate segmented switch terminal as the target loop-breaking segmented switch terminal.

[0043] Understandably, in scenarios with moderate phase angle difference, selecting the intermediate segmented switch terminal with moderate loop impedance can meet the requirements for suppressing inrush current while avoiding unnecessarily expanding the loop de-loop range.

[0044] Step S123: In response to the current phase angle difference not exceeding the second phase angle difference threshold, the end segment switch terminal located on the tie switch terminal side of the feeder is identified as the target unloop segment switch terminal.

[0045] The end-of-line sectionalizing switch terminal is the sectionalizing switch terminal located on the side of the tie switch terminal on the feeder line, and the loop impedance between it and the tie switch terminal is the smallest among the multiple sectionalizing switch terminals on the feeder line.

[0046] The main station responds when the current phase angle difference does not exceed the second phase angle difference threshold, confirming that the current operating condition belongs to a low phase angle difference scenario, and identifies the end segment switch terminal as the target loop-breaking segment switch terminal. Both the first and second phase angle difference thresholds are treated as endpoints of closed intervals. When the current phase angle difference is equal to the first phase angle difference threshold, it is classified as falling under the case where it does not exceed the first phase angle difference threshold; when the current phase angle difference is equal to the second phase angle difference threshold, it is classified as falling under the case where it does not exceed the second phase angle difference threshold, ensuring that the three scenario types cover the entire range of the current phase angle difference value.

[0047] Understandably, the loop inrush current is already within the allowable range in low phase angle difference scenarios. By selecting the end sectionalizing switch terminal with the smallest loop impedance, the impact of the loop breaking operation on the line load transfer range can be minimized.

[0048] It should be noted that step S12 compares the current phase angle difference with the first phase angle difference threshold and the second phase angle difference threshold, and selects segmented switch terminals with corresponding loop impedances for the high, medium and low scenarios respectively, so that the selection of the target loop-breaking segmented switch terminal is directly related to the current operating conditions, and ensures that the inrush current of the loop-breaking operation is within the allowable range from the preset stage.

[0049] Step S13: Combine the identifier of the target loop-breaking section switch terminal with the identifier of the tie switch terminal to generate a preset command, and send the preset command to the tie switch terminal and the target loop-breaking section switch terminal.

[0050] The identifiers of the target loop-breaking section switch terminal and the tie switch terminal are unique coded information that identifies their respective positions on the feeder. The pairing relationship is the correspondence between the tie switch terminal and the target loop-breaking section switch terminal. After receiving the loop-closing action signal, the target loop-breaking section switch terminal confirms and executes the loop-breaking action based on the pairing relationship.

[0051] The master station encapsulates the identifier of the target loop-breaking section switch terminal and the identifier of the tie switch terminal into a preset command, and sends it to both the tie switch terminal and the target loop-breaking section switch terminal respectively. After receiving the preset command, both ends store the pairing relationship locally for pairing verification after the target loop-breaking section switch terminal receives the loop-closing action signal in step S3.

[0052] It should be noted that, in addition to the pairing relationship, the preset instruction also needs to provide parameter support for the phase angle difference verification and timing compensation before loop closure in step S2 of the contact switch terminal. If the phase angle difference safety threshold and transmission lag duration are temporarily requested from the master station during the execution phase, additional communication round-trip delay will be introduced. To solve the above problem, in some embodiments, the preset instruction generated by combining the identifier of the target loop-breaking segment switch terminal and the identifier of the contact switch terminal in step S13 includes steps S131 to S134: Step S131: Retrieve the location identifiers of the target unlooping sectionalizing switch terminal and the tie switch terminal.

[0053] The location identifiers of the target loop-breaking section switch terminal and the tie switch terminal are coded information retrieved from the master station system ledger, which uniquely identify the positions of the target loop-breaking section switch terminal and the tie switch terminal on the feeder.

[0054] The main station retrieves the location identifiers of the target loop-breaking section switch terminal and the tie switch terminal from the system ledger, which serve as the base fields for generating preset instructions in steps S132 to S134. The location identifiers act as the carrier of the pairing relationship in the preset instructions. After receiving the loop-closing action signal, the target loop-breaking section switch terminal confirms the pairing relationship by comparing the location identifiers. After receiving the loop-breaking action signal in step S4, the tie switch terminal verifies whether the operation object matches the preset by comparing the location identifiers.

[0055] The introduction of location identifiers enables preset instructions to have a unique identifier for the operation object, providing a comparable basis for pairing verification in steps S3 and S4.

[0056] Step S132: Calculate the phase angle difference safety threshold corresponding to the target loop-breaking section switch terminal based on the loop impedance between the target loop-breaking section switch terminal and the tie switch terminal and the current phase angle difference.

[0057] The phase angle difference safety threshold is the upper limit of the phase angle difference corresponding to the maximum allowable inrush current of the line, under the loop impedance conditions between the target unlooping sectionalizing switch terminal and the tie switch terminal. The loop impedance between the target unlooping sectionalizing switch terminal and the tie switch terminal is obtained from the master station system ledger, and the current phase angle difference value comes from the calculation result of step S11.

[0058] The main station calculates the upper limit of the voltage difference between the two ends by multiplying the maximum allowable inrush current of the line by the loop impedance between the target disconnect sectionalizing switch terminal and the tie switch terminal. This upper limit is then combined with the line's rated voltage to calculate the phase angle difference safety threshold. The calculation process for the phase angle difference safety threshold is as follows: the product of the maximum allowable inrush current of the line and the loop impedance between the target disconnect sectionalizing switch terminal and the tie switch terminal is used as the maximum allowable voltage difference amplitude when the loop is closed; then, the ratio of the maximum voltage difference amplitude to the line's rated phase voltage is used as the arcsine value to obtain the corresponding upper limit of the phase angle difference, which is the phase angle difference safety threshold. The maximum allowable inrush current of the line is determined by the line protection settings, and the loop impedance between the target disconnect sectionalizing switch terminal and the tie switch terminal is obtained from the main station system ledger.

[0059] Understandably, the phase angle difference safety threshold is calculated and encapsulated into the preset instruction during the preset stage. The contact switch terminal directly reads and compares it with the real-time phase angle difference value in step S2, without needing to request the verification basis from the master station during the execution stage, thus reducing the dependence of the execution stage on the master station.

[0060] Step S133: Measure the communication delay through the 5G wireless communication link between the main station and the contact switch terminal, and calculate the transmission lag time based on the communication delay.

[0061] Communication delay is the transmission time between the loop closing action signal being sent from the tie switch terminal and received by the target loop unclosing segment switch terminal, measured through the 5G wireless communication link between the master station and the tie switch terminal. Transmission lag is the time the tie switch terminal waits to send the loop closing action signal after the loop closing action is completed, calculated based on the communication delay.

[0062] The master station sends measurement messages to the liaison switch terminal and records the round-trip time, taking half of the round-trip time as the one-way communication delay. The transmission lag is calculated by the master station based on the communication delay. The specific calculation process is as follows: The master station sends measurement messages to the liaison switch terminal and records the round-trip time of the messages, taking half of the round-trip time as the estimated one-way communication delay between the master station and the liaison switch terminal; considering that the loop closing action signal needs to be transmitted through the 5G wireless communication link between the liaison switch terminal and the target loop breaking segment switch terminal after being sent from the liaison switch terminal, the estimated one-way communication delay of the 5G wireless communication link is added to the estimated one-way communication delay between the master station and the liaison switch terminal to obtain the estimated total transmission delay from the sending of the loop closing action signal from the liaison switch terminal to the receiving of the target loop breaking segment switch terminal, which is the transmission lag.

[0063] Understandably, the transmission latency of 5G wireless communication links fluctuates due to factors such as network load and base station distance. If compensation is not made for the transmission time, the arrival time of the loop closing action signal at the target loop breaking segment switch terminal will be offset due to latency fluctuations, resulting in a timing deviation between the loop closing and loop breaking actions. By measuring the communication latency in the preset phase and incorporating the transmission lag time into the preset command, the handover switch terminal directly adjusts the transmission time according to the transmission lag time during the execution phase, eliminating the need for temporary calculations.

[0064] Step S134: Combine the location identifier of the target unloop segment switch terminal, the location identifier of the tie switch terminal, the phase angle difference safety threshold, and the transmission lag time to generate a preset command.

[0065] The location identifier of the target unloop segment switch terminal, the location identifier of the tie switch terminal, the phase angle difference safety threshold, and the transmission lag time are four parameters retrieved and calculated in steps S131 to S133 respectively.

[0066] The master station encapsulates the four parameters according to the preset instruction message format and sends them to the liaison switch terminal and the target deloop segment switch terminal respectively. After storing the preset instruction, the liaison switch terminal reads the phase angle difference safety threshold for pre-loop closure verification and reads the transmission lag time for timing compensation in step S2. After storing the preset instruction, the target deloop segment switch terminal reads the position identifier for pairing verification in step S3.

[0067] It should be noted that in steps S131 to S134, the location identifier, phase angle difference safety threshold, and transmission lag duration are encapsulated into the preset instruction during the preset stage. All parameters required by the communication switch terminal and the target loop-breaking segment switch terminal during the execution stage are obtained from the stored preset instruction, eliminating the possibility of additional communication round trips introduced by parameter acquisition during the execution stage, and providing a complete parameter basis for the rapid linkage execution of steps S2 and S3.

[0068] Step S14: After both the tie switch terminal and the target unlooping section switch terminal return the preset success signal, the master station sends a closing and unlooping execution command to the tie switch terminal.

[0069] The preset success signal is an acknowledgment signal returned to the master station by the communication switch terminal and the target unlooping segment switch terminal after completing the local storage of the preset command.

[0070] After receiving preset success signals from both the tie switch terminal and the target loop-breaking section switch terminal, the master station confirms that both ends are ready and issues a loop-breaking / breaking execution command to the tie switch terminal. If either terminal fails to return a preset success signal within a preset time, the master station will not issue a loop-breaking / breaking execution command to avoid initiating the loop-breaking / breaking operation before configuration is complete. The specific value of the preset time can be selected by those skilled in the art based on the typical completion time stored locally on the terminal and the normal network response latency.

[0071] It is understandable that using the pre-set success signal at both ends as a prerequisite for issuing the loop-break execution command ensures that both the tie switch terminal and the target loop-break section switch terminal have completed parameter storage before the operation starts, thus avoiding the risk of missing pairing relationship during the execution phase due to single-end pre-set failure.

[0072] Preferably, step S1 incorporates the current operating conditions into the selection criteria for the target loop-breaking segment switch terminal by collecting the real-time voltage phase angles on both sides of the interconnection switch terminal. Furthermore, during the preset phase, the phase angle difference safety threshold and the transmission lag time are encapsulated into a preset command. During the execution phase, the actions of both the interconnection switch terminal and the target loop-breaking segment switch terminal are triggered based on the parameters in the preset command, eliminating the need for additional interaction with the master station and thus removing parameter dependencies for the rapid coordinated execution of steps S2 and S3.

[0073] Step S2: After receiving the closing and unclosing loop execution command, the communication switch terminal performs the closing loop action and sends the closing loop action signal to the segment switch terminal in a point-to-point manner via 5G wireless communication.

[0074] The loop closure / reopening execution command is an operation start signal issued by the master station to the liaison switch terminal after confirming that both the liaison switch terminal and the target loop closure section switch terminal have completed their presets. The loop closure action is the operation of the liaison switch terminal switching its local switch from the open position to the closed position. The loop closure action signal is a trigger signal sent by the liaison switch terminal to the target loop closure section switch terminal via 5G wireless communication in a point-to-point manner after the loop closure action is completed, used to notify the target loop closure section switch terminal to execute the loop closure action.

[0075] After receiving the loop closing / opening execution command, the liaison switch terminal reads the phase angle difference safety threshold from the preset command, collects the real-time voltage phase angles on both sides of its own terminal, calculates the real-time phase angle difference, and compares it with the phase angle difference safety threshold to determine whether to perform the loop closing action. After the loop closing action is completed, the liaison switch terminal reads the transmission lag time from the preset command, and after a delay of the transmission lag time, sends the loop closing action signal to the target loop opening section switch terminal via 5G wireless communication in a point-to-point manner, triggering the target loop opening section switch terminal to perform the loop opening action.

[0076] The loop closing action signal is sent directly from the tie switch terminal to the target loop breaking section switch terminal without passing through the master station. Upon receiving the loop closing action signal, the target loop breaking section switch terminal can trigger the loop breaking action, enabling the linkage between tie switch loop closing and section switch loop breaking to be completed directly at the terminal level.

[0077] It should be noted that between receiving the loop closing / unclosing execution command and executing the loop closing action, there may be situations where the real-time phase angle difference exceeds the safe range due to changes in operating conditions. For example, after the master station issues the loop closing / unclosing execution command, the system power flow changes, and the phase angle difference on both sides of the tie switch terminal rises to above the safe phase angle difference threshold in a short period of time. If the tie switch terminal executes the loop closing action directly without verification, it will generate an inrush current exceeding the allowable range of the line. Traditional methods do not perform secondary verification of the real-time phase angle difference during the execution phase, and cannot cope with changes in operating conditions after the preset is completed. To solve the above problems, in some embodiments, step S2 includes steps S21 to S24: Step S21: After receiving the closing and opening loop execution command, the tie switch terminal reads the phase angle difference safety threshold in the preset command, collects the current voltage phase angle on both sides of the tie switch terminal, and calculates the real-time phase angle difference value.

[0078] The phase angle difference safety threshold is the basis for the loop closure safety judgment calculated in step S132 and encapsulated in the preset instruction. It is read by the tie switch terminal from the stored preset instruction. The real-time phase angle difference value is the absolute value of the difference between the phase angles of the voltages on both sides collected by the tie switch terminal at the moment of receiving the loop closure execution instruction. It reflects the actual operating conditions at the moment the loop closure execution instruction is issued.

[0079] After receiving the loop closing and closing execution command, the tie switch terminal reads the phase angle difference safety threshold from the preset command stored locally. At the same time, it collects the real-time voltage phase angle between the substation side and the feeder on the opposite side of the tie switch terminal through the local voltage transformer, calculates the difference between the two voltage phase angles and takes the absolute value to obtain the real-time phase angle difference value, which is used as the input for the pre-loop closing verification in steps S22 and S23.

[0080] The real-time phase angle difference is collected at the moment the closing and unclosing loop execution command is issued, reflecting the possible changes in operating conditions between the completion of the preset and the issuance of the execution command. This provides a real-time data basis for the tie switch terminal to independently complete the phase angle difference verification before closing the loop during the execution phase.

[0081] Step S22: Compare the real-time phase angle difference with the phase angle difference safety threshold. If the real-time phase angle difference does not exceed the phase angle difference safety threshold, the interconnection switch terminal performs a loop closing action.

[0082] Both the real-time phase angle difference and the phase angle difference safety threshold are phase angle difference values ​​in degrees. The interconnection switch terminal directly compares the real-time phase angle difference with the phase angle difference safety threshold.

[0083] When the tie switch terminal responds to the real-time phase angle difference not exceeding the phase angle difference safety threshold, it determines that the closing inrush current under the current operating condition is within the allowable range, and sends a closing command to the local switch control circuit, driving the tie switch to complete the switching from the open position to the closed position, thus completing the closing action. If the real-time phase angle difference is equal to the phase angle difference safety threshold, it is treated as not exceeding it and classified as a case where the closing action can be performed.

[0084] During the execution phase, the real-time phase angle difference is compared with the phase angle difference safety threshold, enabling the tie switch terminal to have independent loop closing safety judgment capability after receiving the loop closing and closing execution command, without needing to send an additional request to the master station, thus avoiding the risk of the loop closing inrush current exceeding the limit due to changes in operating conditions after the preset is completed.

[0085] Step S23: In response to the real-time phase angle difference exceeding the phase angle difference safety threshold, a phase angle difference over-limit signal is reported to the master station. After the master station sends a compensation completion signal containing the phase angle difference after voltage regulation, the tie switch terminal performs the loop closing action again.

[0086] The phase angle difference exceeding limit signal is an alarm signal reported by the tie switch terminal to the master station when the real-time phase angle difference exceeds the phase angle difference safety threshold. It includes two data points: the real-time phase angle difference and the phase angle difference safety threshold. The compensation completion signal is a confirmation signal sent by the master station to the tie switch terminal after the voltage regulating equipment on the substation side has completed voltage regulation and the phase angle difference after voltage regulation does not exceed the phase angle difference safety threshold. It includes the phase angle difference after voltage regulation.

[0087] It should be noted that after the tie switch terminal reports a phase angle difference exceeding the limit signal to the master station, if the master station needs to re-collect the voltage phase angles on both sides of the tie switch terminal to calculate the required compensation, an additional round-trip communication is required, prolonging the voltage regulation waiting time. To avoid the aforementioned additional round-trip communication, the phase angle difference exceeding the limit signal includes the real-time phase angle difference value already collected by the tie switch terminal and the phase angle difference safety threshold read from the preset command. After receiving the phase angle difference exceeding the limit signal, the master station directly calculates the required compensation based on the two data points in the signal, without needing to re-initiate a collection request to the tie switch terminal. In some embodiments, step S23 includes steps S231 to S234: Step S231: The contact switch terminal reports a phase angle difference exceeding the limit signal to the master station.

[0088] The phase angle difference exceeding the limit signal is composed of the real-time phase angle difference value calculated by the handshake switch terminal in step S21 and the phase angle difference safety threshold read from the preset instruction, and is reported to the main station through the 5G wireless communication link between the handshake switch terminal and the main station.

[0089] In response to the judgment result in step S22 that the real-time phase angle difference exceeds the phase angle difference safety threshold, the contact switch terminal encapsulates the real-time phase angle difference and the phase angle difference safety threshold into a phase angle difference over-limit signal, sends it to the master station through the 5G wireless communication link, suspends the loop closing action, and waits for the master station to send a compensation completion signal.

[0090] The phase angle difference over-limit signal contains the real-time phase angle difference value and the phase angle difference safety threshold. After receiving the signal, the master station can directly extract the two data points to calculate the required compensation amount, eliminating the communication round trip of the master station to re-acquire the voltage phase angle and shortening the time interval between the over-limit report and the issuance of the voltage regulation command.

[0091] Step S232: The master station calculates the required compensation amount based on the real-time phase angle difference and the phase angle difference safety threshold, and issues a voltage regulation command to the voltage regulating equipment on the substation side according to the required compensation amount.

[0092] The required compensation amount is the voltage regulation target value calculated by the master station based on the real-time phase angle difference value in the phase angle difference over-limit signal and the phase angle difference safety threshold. It reflects the extent to which the phase angle difference between the two sides of the tie switch terminal needs to be reduced through voltage regulation. The substation-side voltage regulating equipment is a voltage regulation device that is communicatively connected to the master station. It can reduce the phase angle difference between the two sides of the tie switch terminal by adjusting the phase angle of the substation-side outlet voltage. The voltage regulation command is a control signal issued by the master station to the substation-side voltage regulating equipment based on the required compensation amount.

[0093] The master station extracts the real-time phase angle difference value and the phase angle difference safety threshold from the phase angle difference over-limit signal. The difference between the real-time phase angle difference value and the phase angle difference safety threshold is used as the required compensation amount. The required compensation amount is encapsulated as a voltage regulation command and sent to the voltage regulation equipment on the substation side. The voltage regulation equipment on the substation side adjusts the phase angle of the substation side outlet voltage according to the voltage regulation command, so that the phase angle difference on both sides of the tie switch terminal converges to within the phase angle difference safety threshold.

[0094] The required compensation amount is calculated directly by the master station and then sent to the voltage regulating equipment on the substation side, so that the target of the voltage regulation operation directly corresponds to the phase angle difference safety threshold, avoiding multiple voltage regulation round trips caused by the estimation error of the voltage regulation amount.

[0095] Step S233: After the voltage regulation equipment on the substation side completes the voltage regulation, the main station re-collects the voltage phase angles on both sides of the tie switch terminal, calculates the phase angle difference after voltage regulation, and after confirming that the phase angle difference after voltage regulation does not exceed the safe threshold for phase angle difference, the phase angle difference after voltage regulation is included in the compensation completion signal and a compensation completion signal is sent to the tie switch terminal.

[0096] The phase angle difference after voltage regulation is the phase angle difference calculated by the master station after the voltage regulation equipment on the substation side has completed the voltage regulation, by re-collecting the voltage phase angles on both sides of the tie switch terminal. It is used to confirm whether the voltage regulation result meets the closed-loop safety conditions. The compensation completion signal is a confirmation signal sent by the master station to the tie switch terminal after confirming that the phase angle difference after voltage regulation does not exceed the phase angle difference safety threshold. It includes the phase angle difference after voltage regulation.

[0097] After receiving feedback from the substation-side voltage regulating equipment that the voltage regulation is complete, the master station re-initiates a voltage phase angle acquisition request to the tie switch terminal, calculates the phase angle difference after voltage regulation, and compares the phase angle difference with the phase angle difference safety threshold. If the phase angle difference after voltage regulation does not exceed the phase angle difference safety threshold, the master station encapsulates the phase angle difference into a compensation completion signal and sends it to the tie switch terminal. If the phase angle difference after voltage regulation still exceeds the phase angle difference safety threshold, the master station recalculates the required compensation amount and sends the voltage regulation command again. Those skilled in the art can pre-configure an upper limit for the number of voltage regulation retry attempts in the master station based on the voltage regulation capability of the substation-side voltage regulating equipment and the line operation procedures. If the phase angle difference after voltage regulation still exceeds the phase angle difference safety threshold after the upper limit is reached, the master station sends an operation termination signal to the tie switch terminal. Upon receiving the operation termination signal, the tie switch terminal abandons the current loop closure and reports a voltage regulation over-limit failure signal to the master station.

[0098] The master station can only send a compensation completion signal after confirming that the phase angle difference after voltage regulation does not exceed the phase angle difference safety threshold. This ensures that the current operating condition of the tie switch terminal meets the loop closing safety conditions when it receives the compensation completion signal, thus avoiding the risk of excessive loop closing inrush current due to insufficient voltage regulation.

[0099] Step S234: After receiving the compensation completion signal containing the phase angle difference after voltage regulation, the tie switch terminal performs the loop closing action.

[0100] The phase angle difference after voltage regulation is the phase angle difference value confirmed by the master station after being extracted from the compensation completion signal. The tie switch terminal extracts the phase angle difference after voltage regulation from the compensation completion signal and compares it again with the phase angle difference safety threshold in the preset command. In response to the phase angle difference after voltage regulation not exceeding the phase angle difference safety threshold, the tie switch terminal sends a closing command to the local switch control circuit to execute the loop closing action.

[0101] After receiving the compensation completion signal, the liaison switch terminal compares the phase angle difference after voltage regulation again, instead of directly trusting the master station's judgment on compensation completion. If the phase angle difference after voltage regulation carried by the compensation completion signal is inconsistent with the master station's side during communication, the liaison switch terminal can independently detect the anomaly and refuse to perform the loop closing action, thus adding a security check on the terminal side for the loop closing operation.

[0102] It should be noted that in step S23, the tie switch terminal reports a phase angle difference exceeding the limit signal, which includes the real-time phase angle difference value and the phase angle difference safety threshold, to the master station. This triggers the master station to complete voltage regulation and confirm with a compensation completion signal. After receiving the compensation completion signal, the tie switch terminal compares the phase angle difference value after voltage regulation again before executing the loop closing action. Compared to fixing the loop closing conditions once in the preset stage, step S23 introduces real-time response and closed-loop confirmation for changes in operating conditions during the execution stage. This ensures that even if changes in operating conditions occur between the completion of the preset operation and the issuance of the execution command, the loop closing inrush current remains within the allowable range.

[0103] Step S24: After the loop closing action is completed, the communication switch terminal reads the transmission lag time in the preset instruction, performs lag compensation on the transmission time of the loop closing action signal according to the transmission lag time, and sends the loop closing action signal to the target de-loop segment switch terminal in a point-to-point manner through 5G wireless communication.

[0104] The transmission lag duration is a timing compensation parameter calculated based on the communication delay in step S133 and encapsulated in the preset instruction. It is read by the liaison switch terminal from the stored preset instructions. Lag compensation is the operation where the liaison switch terminal delays the transmission lag duration based on the loop-closing action completion time before issuing the loop-closing action signal. The loop-closing action signal is a trigger signal sent directly from the liaison switch terminal to the target loop-breaking segment switch terminal via 5G wireless communication in a point-to-point manner. It includes the location identifier of the liaison switch terminal and the loop-closing completion time.

[0105] It should be noted that there is a communication transmission delay between the completion time of the loop closing action and the arrival time of the loop closing action signal at the target de-looping sectionalizing switch terminal. If the tie switch terminal sends the loop closing action signal immediately after the loop closing action is completed, the signal will arrive at the target de-looping sectionalizing switch terminal later than the completion time of the loop closing action, and the delay is equal to the communication delay. For example, in a scenario where the communication delay is tens of milliseconds, when the target de-looping sectionalizing switch terminal receives the loop closing action signal and begins to execute the de-looping action, the tie switch has already completed the loop closing and has been running under load for the corresponding duration. The timing deviation between the loop closing and de-looping will cause the short-term parallel operation time of the two power supplies to exceed the expectation. In the traditional method, the loop closing action signal is relayed through the master station, and the master station can actively compensate for the delay during forwarding. However, in the scenario where the tie switch terminal and the target de-looping sectionalizing switch terminal communicate directly, the timing compensation must be completed autonomously by the tie switch terminal. To solve the above problem, in some embodiments, step S24 includes steps S241 to S243: Step S241: The interconnecting switch terminal monitors the local switch position signal. In response to the local switch position signal changing from open to closed, it confirms that the loop closing action is completed and records the time when the local switch position signal changes from open to closed as the loop closing completion time.

[0106] The local switch position signal is the real-time acquisition of the local switch's open / closed status signal by the tie switch terminal, with a value indicating either open or closed. The loop completion time is the moment when the local switch position signal changes from open to closed, recorded by the tie switch terminal using its local clock.

[0107] After issuing the closing command, the interconnecting switch terminal continuously monitors the local switch position signal. In response to the local switch position signal changing from open to closed, it determines that the closing action has been completed. The local clock records this moment as the closing completion moment, which serves as the starting reference for the delayed waiting in step S242.

[0108] The closing loop completion time is determined by the moment when the switch position signal changes from open to closed, rather than by the moment the closing command is issued. This eliminates the impact of the mechanical action delay between the issuance of the closing command and the actual completion of the switch action on the timing compensation accuracy.

[0109] Step S242: Read the transmission lag time in the preset instruction, and wait for the lag time based on the loop closure completion time.

[0110] The transmission delay duration is read from the preset instructions stored locally in the communication switch terminal. Starting from the time of loop closure completion, the communication switch terminal starts local timing, waits for the time interval corresponding to the transmission delay duration, and then ends the delay wait, proceeding to step S243.

[0111] Based on the completion time of the loop closure, a delay waiting period is applied to ensure that the time when the loop closure action signal leaves the contact switch terminal is delayed by the transmission delay period compared to the completion time of the loop closure. The interval between the time when the loop closure action signal arrives at the target de-looping segment switch terminal after the communication delay is controlled, thus compensating for the impact of communication transmission delay on the timing coordination of loop closure and de-looping.

[0112] Step S243: After the delay period ends, the communication switch terminal sends a loop closing action signal to the target loop unblocking segment switch terminal in a point-to-point manner via 5G wireless communication.

[0113] The loop closing action signal is encapsulated by combining the location identifier of the tie switch terminal and the loop closing completion time. It is transmitted directly to the target loop breaking segment switch terminal via a 5G wireless communication link in a point-to-point manner, without being forwarded by the main station. The target loop breaking segment switch terminal extracts the location identifier of the tie switch terminal from the loop closing action signal, compares it with the pairing relationship in the preset command, and executes the loop breaking action after confirming that the pairing is consistent; at the same time, it extracts the loop closing completion time for the calculation of the loop closing and breaking time difference in step S4.

[0114] The loop closing action signal is sent directly to the target loop breaking section switch terminal in a point-to-point manner, eliminating the relay link of the master station. This allows the target loop breaking section switch terminal to trigger the loop breaking action immediately upon receiving the loop closing action signal, realizing direct linkage between the tie switch loop closing and the section switch loop breaking at the terminal level.

[0115] It should be noted that step S24, by delaying the transmission of the loop-closing action signal based on the loop-closing completion time and the transmission delay duration, removes the impact of communication transmission delay from the timing coordination of loop-closing and loop-breaking. This ensures that the interval between the time the target loop-breaking section switch terminal receives the loop-closing action signal and the loop-closing completion time is within a controllable range. The loop-closing action signal is transmitted directly in a point-to-point manner, eliminating the additional delay introduced by the master station relay while completing timing compensation. This ensures that the linkage timing between the tie switch loop-closing and the section switch loop-breaking simultaneously meets the requirements of speed and accuracy.

[0116] Preferably, step S2 compares the real-time phase angle difference with the phase angle difference safety threshold before executing the loop closing action. If the operating conditions meet the safety requirements, the loop closing action is executed directly. If the operating conditions do not meet the requirements, the voltage regulation closed loop is triggered before execution, ensuring that the loop closing operation does not generate an inrush current exceeding the allowable range under any change in operating conditions. After the loop closing action is completed, the loop closing action signal is sent directly to the target unlooping sectionalizing switch terminal in a point-to-point manner, eliminating the master station relay link. The communication transmission delay is compensated by the transmission lag time, so that the linkage between the tie switch loop closing and the sectionalizing switch loop opening is completed directly at the terminal level, while ensuring the accuracy of timing coordination.

[0117] Step S3: After receiving the loop closing action signal, the sectionalizing switch terminal performs the loop closing action according to the pairing relationship in the stored preset instructions, and returns the loop closing action signal to the tie switch terminal.

[0118] The pairing relationship is the correspondence between the connecting switch terminal and the target loop-breaking switch terminal, which is encapsulated in the preset instruction and stored locally by the target loop-breaking switch terminal in step S13. The loop-breaking action is the operation by which the target loop-breaking switch terminal switches its local switch from the closed position to the open position. The loop-breaking action signal is a confirmation signal returned by the target loop-breaking switch terminal to the connecting switch terminal after the loop-breaking action is completed, containing the location identifier of the target loop-breaking switch terminal and the loop-breaking completion time.

[0119] After receiving the closing action signal, the target loop-breaking section switch terminal reads the pairing relationship from the locally stored preset instructions. It compares the position identifier of the connecting switch terminal carried in the closing action signal with the position identifier of the connecting switch terminal in the pairing relationship. After confirming that they match, it sends a tripping command to the local switch control circuit, driving the local switch to complete the switchover from the closed position to the open position, thus completing the loop-breaking action. After the loop-breaking action is completed, the target loop-breaking section switch terminal encapsulates the local position identifier and the loop-breaking completion time into a loop-breaking action signal, which is directly returned to the connecting switch terminal via a 5G wireless communication link in a point-to-point manner.

[0120] After receiving the loop closing action signal, the target loop-breaking segment switch terminal independently completes the loop-breaking trigger judgment based on the locally stored pairing relationship, without needing to request confirmation from the master station. This allows the loop-breaking action to be directly triggered via point-to-point communication after the tie switch is closed, eliminating the impact of the master station relay link on the loop-breaking response time.

[0121] It should be noted that multiple segmented switching terminals are deployed on the feeder. Each segmented switching terminal, upon receiving a loop-closing action signal, must determine whether the target segmented switching terminal for this loop-closing operation is itself. If a segmented switching terminal triggers a loop-closing action solely based on receiving the loop-closing action signal without verifying the pairing relationship, other non-target segmented switching terminals on the feeder may also erroneously perform loop-closing, causing an unexpected line disconnection. To address this issue, in some embodiments, step S3 includes steps S31 and S32: Step S31: The segmented switch terminal determines the corresponding target unlooping segmented switch terminal according to the pairing relationship in the preset instruction, and performs the unlooping action after receiving the loop closing action signal.

[0122] The pairing relationship is obtained from the preset instructions stored locally on the sectionalizing switch terminal, which includes the location identifier of the connecting switch terminal and the location identifier of the target loop-breaking sectionalizing switch terminal. After receiving the loop-closing action signal, the sectionalizing switch terminal extracts the location identifier of the connecting switch terminal from the loop-closing action signal and compares it with the location identifier of the connecting switch terminal recorded in the pairing relationship in the local preset instructions. If the two match and the local location identifier matches the location identifier of the target loop-breaking sectionalizing switch terminal in the pairing relationship, the local terminal is confirmed as the target loop-breaking sectionalizing switch terminal, and the loop-breaking action is executed; if the comparison does not match, the local sectionalizing switch terminal does not execute any action.

[0123] Specifically, the types of target loop-breaking segmented switch terminals include the following three cases: Scenario 1: In response to the target loop-breaking segment switch terminal being the first segment switch terminal, the first segment switch terminal reads the pairing relationship from its local preset instructions. After confirming that it is the target loop-breaking segment switch terminal, it executes the loop-breaking action. The loop-breaking action signal contains the location identifier of the first segment switch terminal and the loop-breaking completion time. The connection switch terminal extracts the location identifier of the first segment switch terminal and the loop-breaking completion time from the loop-breaking action signal for calculation of the loop-breaking time difference and verification of the pairing relationship in step S4. Scenario 2: In response to the target loop-breaking segment switch terminal being an intermediate segment switch terminal, the intermediate segment switch terminal reads the pairing relationship from its local preset instructions. After confirming that it is the target loop-breaking segment switch terminal, it executes the loop-breaking action. The loop-breaking action signal contains the location identifier of the intermediate segment switch terminal and the loop-breaking completion time. The connection switch terminal extracts the location identifier of the intermediate segment switch terminal and the loop-breaking completion time from the loop-breaking action signal for calculation of the loop-breaking time difference and verification of the pairing relationship in step S4. Scenario 3: In response to the target loop-breaking segment switch terminal being the end segment switch terminal, the end segment switch terminal reads the pairing relationship from its local preset instructions. After confirming that it is the target loop-breaking segment switch terminal, it executes the loop-breaking action. The loop-breaking action signal contains the location identifier of the end segment switch terminal and the loop-breaking completion time. The connecting switch terminal extracts the location identifier of the end segment switch terminal and the loop-breaking completion time from the loop-breaking action signal for calculation of the loop-breaking time difference and verification of the pairing relationship in step S4.

[0124] The three scenarios cover all possible types of target loop-breaking segment switch terminals on the feeder. The content structure of the loop-breaking action signal is the same in each scenario, including the location identifier of the target loop-breaking segment switch terminal and the loop-breaking completion time, ensuring that the verification logic of the contact switch terminal in step S4 is uniformly applicable to the three scenarios.

[0125] It should be noted that step S31 compares and verifies the pairing relationship after the target deloop segment switch terminal receives the loop closing action signal, so that the triggering of the deloop action is based on the consistency of the pairing relationship. This avoids the risk of non-target segment switch terminals on the feeder malfunctioning due to receiving the loop closing action signal. At the same time, it allows the target deloop segment switch terminal to trigger the deloop action independently after confirming the pairing relationship, without needing to send a confirmation request to the main station.

[0126] Step S32: After the loop-breaking action is completed, the time when the switch position signal of the target loop-breaking section switch terminal changes from closed to open is taken as the reference. Record the loop-breaking completion time and return the loop-breaking action signal to the tie switch terminal.

[0127] The switch position signal is the local switch open / closed status signal acquired in real time by the target loop-breaking segment switch terminal, and its value is either "closed" or "open". The loop-breaking completion time is the moment when the switch position signal changes from "closed" to "open", which is recorded by the target loop-breaking segment switch terminal using its local clock.

[0128] After issuing the trip command, the target loop-breaking section switch terminal continuously monitors the local switch position signal. In response to the switch position signal changing from closed to open, it determines that the loop-breaking action has been completed. The local clock records this moment as the loop-breaking completion moment. The position identifier of the target loop-breaking section switch terminal and the loop-breaking completion moment are encapsulated into a loop-breaking action signal and sent directly to the contact switch terminal in a point-to-point manner through the 5G wireless communication link.

[0129] It is understandable that using the moment the tripping command is issued instead of the moment the switch position signal changes from closed to open to record the loop-breaking completion time introduces a mechanical action delay between the issuance of the tripping command and the actual completion of the switch action. This causes the recorded loop-breaking completion time to be earlier than the actual opening time of the switch, resulting in a smaller loop-breaking time difference calculated in step S4, affecting the accuracy of timing verification. Recording the loop-breaking completion time based on the moment the switch position signal changes from closed to open eliminates the impact of mechanical action delay on the accuracy of the loop-breaking completion time recording. This is consistent with the method in step S241 where the connecting switch terminal records the loop-closing completion time based on the moment its own switch position signal changes from open to closed, aligning the calculation benchmark for the loop-breaking time difference in step S4 between the loop-closing and loop-breaking sides.

[0130] It should be noted that step S32 uses the actual change time of the switch position signal as the recording basis for the completion time of the loop unwinding, which is consistent with the recording method of the completion time of the loop closing in step S241 in terms of time reference. This ensures that the loop closing and unwinding time difference calculated by the two in step S4 accurately reflects the actual time interval between the completion of the loop closing action and the completion of the loop unwinding action, and provides reliable input data for the comparison of the loop closing and unwinding time difference with the preset synchronization time window in step S42.

[0131] Preferably, in step S3, after receiving the loop-closing action signal, the target loop-breaking segment switch terminal independently completes the loop-breaking trigger judgment and executes the loop-breaking action based on the locally stored pairing relationship. The loop-breaking action signal is directly returned to the tie switch terminal in a point-to-point manner, without passing through the master station. The target loop-breaking segment switch terminal records the loop-breaking completion time based on the actual change time of the switch position signal and incorporates it into the loop-breaking action signal, so that the timing verification in step S4 has an accurate time reference on the loop-breaking side, realizing direct linkage and closed-loop confirmation of tie switch loop-breaking and segment switch loop-breaking at the terminal level.

[0132] Step S4: The tie switch terminal determines the execution result of this loop closing / closing operation based on the loop breaking action signal, the local line current signal, and the local switch position signal.

[0133] The loop-breaking action signal is a confirmation signal returned by the target loop-breaking section switch terminal in step S32, containing the target loop-breaking section switch terminal's position identifier and the loop-breaking completion time. The local line current signal is the local line current value collected in real-time by the tie switch terminal, reflecting the current-carrying state of the local line after the tie switch is closed. The local switch position signal is the local switch open / closed status signal collected in real-time by the tie switch terminal.

[0134] After receiving the loop-breaking action signal, the tie switch terminal extracts the position identifier of the target loop-breaking section switch terminal and the loop-breaking completion time from the signal. At the same time, it collects the local line current signal and the local switch position signal. The time when the local switch position signal changes from open to closed is taken as the loop-closing completion time. The loop-breaking and closing time difference is calculated by combining the loop-breaking completion time. The position identifier of the target loop-breaking section switch terminal is compared with the target loop-breaking section switch terminal position identifier in the preset command. Based on the verification results of the local line current signal, the local switch position signal and the loop-breaking and closing time difference, the execution result of this loop-breaking and closing operation is determined and reported to the main station.

[0135] It should be noted that the loop closing and opening operation involves coordinated actions at both ends of the tie switch terminal and the target loop opening section switch terminal. An abnormal action at either end may result in an operation outcome that does not meet expectations. If the tie switch terminal only relies on receiving the loop opening action signal to determine the operation's success, without verifying the content of the loop opening action signal, the local line status, or the timing coordination, then operational abnormalities will not be detected in cases of inconsistent target loop opening section switch terminal location identification, loop closing and opening timing deviations, or local line abnormalities. To address the above problems, in some embodiments, step S4 includes steps S41 and S42: Step S41: The interconnecting switch terminal receives the loop-breaking action signal returned by the target loop-breaking section switch terminal, extracts the position identifier and loop-breaking completion time of the target loop-breaking section switch terminal from the loop-breaking action signal, and collects the local line current signal and the local switch position signal. The time when the local switch position signal changes from open to closed is recorded as the loop-closing completion time.

[0136] The position identifier of the target unlooping section switch terminal and the unlooping completion time are extracted from the unlooping action signal. The local line current signal and the local switch position signal are collected by the tie switch terminal through the local current transformer and the switch auxiliary contact. The closing completion time is read from the change time of the local switch position signal recorded in step S241.

[0137] After receiving the loop-breaking action signal, the interconnecting switch terminal parses the signal message to extract the position identifier and loop-breaking completion time of the target loop-breaking section switch terminal. At the same time, it reads the real-time sampling value of the local current transformer as the local line current signal, reads the status of the local switch auxiliary contact as the local switch position signal, and obtains the time when the local switch position signal changes from open to closed from the loop-closing completion time recorded in step S241. The above four data items are used as inputs for multi-dimensional verification in step S42.

[0138] Step S41 collects and extracts the time reference information in the loop-breaking action signal and the real-time status information of the local terminal of the contact switch at the same time, ensuring that the data used for each verification in step S42 reflects the actual status at the time of operation completion, and avoiding deviations in verification conclusions due to inconsistent data collection times.

[0139] Step S42: Calculate the time difference between loop merging and loop unmerging based on the completion time of loop merging and the completion time of loop unmerging, and compare the time difference between loop merging and loop unmerging with the preset synchronization time window configured in the master station to obtain the execution result of this loop merging and loop unmerging operation.

[0140] The time difference between closing and opening loops is the absolute value of the difference between the completion time of opening and closing loops, reflecting the actual time interval between the completion of the closing loop action of the tie switch and the completion of the opening loop action of the target opening segment switch. The preset synchronization time window is the allowable range of closing and opening loop timing pre-configured in the master station. Those skilled in the art can configure it according to the upper limit of the allowed parallel operation time of the two power supplies on the line. The shorter the parallel operation time of the two power supplies, the smaller the preset synchronization time window should be.

[0141] The tie switch terminal calculates the loop closing / unclosing time difference by subtracting the loop closing time from the loop closing time. This time difference is then compared to a preset synchronization time window. Combined with the target loop closing section switch terminal position identifier comparison result, the local line current signal, and the local switch position signal, the execution result of this loop closing / unclosing operation is determined according to the verification logic of steps S421 and S422. In some embodiments, step S42 includes steps S421 and S422: Step S421: Compare the position identifier of the target loop-breaking section switch terminal with the position identifier of the target loop-breaking section switch terminal in the preset instruction, and determine the verification results by combining the local line current signal, the local switch position signal and the loop closing / breaking time difference.

[0142] The position identifier of the target loop-breaking section switch terminal is obtained from the position identifier extracted from the loop-breaking action signal in step S41. The position identifier of the target loop-breaking section switch terminal in the preset command is read from the preset command stored locally in the tie switch terminal. The verification results include the position identifier comparison result, the verification result of the local line current signal from zero to existence, the verification result of the local switch position signal being in the closed position, and the timing verification result of whether the loop-breaking time difference is within the preset synchronization time window.

[0143] The tie switch terminal compares the target loop-breaking section switch terminal position identifier extracted from the loop-breaking action signal with the target loop-breaking section switch terminal position identifier stored in the preset instruction byte by byte to obtain the position identifier comparison result; it checks whether the local line current signal changes from zero to non-zero to obtain the local line current signal status verification result; it checks whether the local switch position signal is in the closed position to obtain the local switch position signal status verification result; and it compares the loop-breaking and closing time difference with the preset synchronization time window to obtain the timing verification result. These four verification results serve as the basis for determining whether the operation is successful or failed in step S422.

[0144] Step S421 verifies the operation result by checking four dimensions: location identifier, local line current signal, local switch position signal and loop closing / closing time difference. This ensures that the operation result is covered by four abnormal scenarios: incorrect pairing relationship, unsuccessful loop closing, unsuccessful loop closing, and timing deviation. Compared with the method of judging the operation result by relying on a single signal, the verification coverage is more comprehensive.

[0145] Step S422: In response to all verification results being passed, the loop merging and unmerging operation is determined to be successful, and a successful loop merging and unmerging signal is reported to the main station.

[0146] Passing all verification results means that all four verification results are met simultaneously: the location identifiers match, the local line current signal changes from zero to positive, the local switch position signal is in the closed position, and the time difference between closing and unclosing the loop is within the preset synchronization time window. The successful closing and unclosing signal is encapsulated by the tie switch terminal and reported to the master station via the 5G wireless communication link. The master station confirms the completion of this closing and unclosing operation based on this signal.

[0147] The loop closing / unclosing operation is deemed a failure in response to any of the following situations, and a loop closing / unclosing failure signal is reported to the master station: The local line current signal does not increase from zero to positive, indicating that the local line is not normally loaded after the tie switch is closed, and the loop closing action may have failed; The location identifier of the target unclosing sectionalizing switch terminal is inconsistent with the location identifier of the target unclosing sectionalizing switch terminal in the preset instruction, indicating that the sectionalizing switch terminal actually performing the unclosing action does not match the preset paired target unclosing sectionalizing switch terminal; The loop closing / unclosing time difference exceeds the preset synchronization time window, indicating that the timing deviation between the loop closing and unclosing actions exceeds the allowable range, and the parallel operation time of the two power supplies exceeds the limit; The tie switch terminal receives a unclosing failure signal returned by the target unclosing sectionalizing switch terminal, indicating that the target unclosing sectionalizing switch terminal failed to complete the unclosing action; The local line current signal reaches the backup protection setting value pre-configured in the tie switch terminal, indicating that an overcurrent has occurred on the local line after the loop closing, requiring protection action to be triggered. The five failure scenarios mentioned above correspond to five types of operational anomalies: abnormal operation on the loop closing side, mismatched pairing relationship, excessive timing deviation, failure to operate on the loop opening side, and overcurrent in the line after loop closing. These scenarios cover the main reasons for possible failures in loop closing and opening operations.

[0148] Preferably, in step S4, after receiving the loop-breaking action signal, the tie switch terminal verifies the four dimensions of the position identifier, the local line current signal, the local switch position signal, and the loop-breaking time difference. The multi-dimensional determination of the loop-breaking operation result is completed at the terminal level without the need for the master station to intervene in the verification process. This allows the determination of the operation result to be completed instantly at the tie switch terminal side, and the determination conclusion is reported to the master station in the form of a loop-breaking success signal or a loop-breaking failure signal. The master station then knows the final execution result of this operation based on this.

[0149] In other embodiments, the present application also includes the following three exception handling scenarios: If the liaison switch terminal does not receive a loop-breaking action signal from the target loop-breaking section switch terminal within a preset time window configured in the liaison switch terminal, the liaison switch terminal performs a tripping action and locks the closing position, reporting a communication timeout failure signal to the master station. The preset time window is a pre-configured timeout judgment criterion in the liaison switch terminal. Those skilled in the art can configure it based on the upper limit of the sum of the transmission lag time and the 5G wireless communication link transmission delay to ensure that the loop-breaking action signal from the target loop-breaking section switch terminal can reach the liaison switch terminal within the preset time window under normal communication conditions. If the liaison switch terminal still does not receive the loop-breaking action signal after the preset time window has expired, it determines that the loop-breaking action signal from the target loop-breaking section switch terminal failed to arrive due to a communication anomaly, performs a tripping action to restore the local switch to the tripped position, simultaneously locks the closing position to prevent re-closing, and reports a communication timeout failure signal to the master station, which then initiates a manual intervention process.

[0150] In response to the disconnection failure signal received by the tie switch terminal from the target disconnection section switch terminal, the tie switch terminal performs a tripping action and blocks the closing action, reporting a section switch disconnection failure signal to the master station. The disconnection failure signal is an abnormal signal returned by the target disconnection section switch terminal to the tie switch terminal when it cannot complete the disconnection action after receiving a closing action signal due to its own switch refusing to operate. Upon receiving the disconnection failure signal, the tie switch terminal determines that the target disconnection section switch terminal's disconnection action was unsuccessful, performs a tripping action to restore its own switch to the open position, simultaneously blocks the closing action, and reports the section switch disconnection failure signal to the master station.

[0151] In response to the local line current signal reaching the backup protection setting pre-configured in the tie switch terminal, the tie switch terminal triggers protection tripping and operates before the substation switches, reporting a backup protection failure signal to the master station. The backup protection setting is the overcurrent protection operating threshold pre-configured in the tie switch terminal, which can be set by those skilled in the art based on the line short-circuit current calculation results and protection coordination requirements. After loop closing, the tie switch terminal continuously monitors the local line current signal. In response to the local line current signal reaching the backup protection setting, it determines that a short circuit or severe overcurrent has occurred on the local line, immediately triggering protection tripping. The tripping action precedes the substation switches, cutting off the fault current at the tie switch terminal side, and reporting a backup protection failure signal to the master station, which then initiates the fault handling procedure.

[0152] The three abnormal handling scenarios correspond to three types of operational failures: communication timeout, failure to operate after loop closure, and line overcurrent after loop closure. In each scenario, the tie switch terminal restores its own switch to a safe state by executing a tripping or protection tripping action and reports the corresponding failure signal to the master station. This ensures that the loop closure and closure operations can trigger a clear backoff action in any abnormal scenario, avoiding the line being in an uncertain operating state. See also Figure 3 This is a timing diagram of a fast merging and unmerging loop device for a distribution network based on 5G communication provided in an embodiment of this application, including: The preset module is used by the master station to send preset instructions to the tie switch terminal and the sectional switch terminal. After the tie switch terminal and the sectional switch terminal return the preset success signal, the master station sends the loop-opening and closing execution instruction to the tie switch terminal. The loop closing module is used to execute the loop closing action after the communication switch terminal receives the loop closing and unclosing execution command, and to send the loop closing action signal to the segment switch terminal in a point-to-point manner via 5G wireless communication. The loop-breaking module is used to execute the loop-breaking action according to the pairing relationship in the stored preset instructions after the sectionalizing switch terminal receives the loop-closing action signal, and return the loop-breaking action signal to the tie switch terminal. The criterion module is used by the interconnecting switch terminal to determine the execution result of the current loop closing / closing operation based on the loop breaking action signal, the local line current signal, and the local switch position signal.

[0153] Figure 3 The apparatus of the illustrated embodiment can be used to perform corresponding actions. Figure 1 The steps in the method embodiments shown are implemented in a similar manner and have similar technical effects, and will not be repeated here.

[0154] See Figure 4 This is a schematic diagram of the hardware structure of an electronic device provided in an embodiment of this application. The electronic device 40 includes: a processor 41, a memory 42, and a computer program; wherein, The memory 42 is used to store the computer program, and the memory may also be flash memory. The computer program is, for example, an application program or functional module that implements the above method.

[0155] The processor 41 is configured to execute the computer program stored in the memory to implement the various steps performed by the device in the above method. For details, please refer to the relevant descriptions in the preceding method embodiments.

[0156] Alternatively, the memory 42 can be either standalone or integrated with the processor 41.

[0157] When the memory 42 is a device independent of the processor 41, the device may further include: Bus 43 is used to connect the memory 42 and the processor 41.

[0158] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A method for rapid loop closing and opening control of distribution networks based on 5G communication, characterized in that, include: The master station sends a preset command to the liaison switch terminal and the sectional switch terminal. After the liaison switch terminal and the sectional switch terminal return a preset success signal, the master station sends a loop-opening / closing execution command to the liaison switch terminal. After receiving the closing and unclosing loop execution command, the communication switch terminal performs the closing loop action and sends the closing loop action signal to the segment switch terminal in a point-to-point manner via 5G wireless communication. After receiving the loop closing action signal, the segmented switch terminal performs a loop breaking action according to the pairing relationship in the stored preset instructions, and returns a loop breaking action signal to the tie switch terminal. The interconnection switch terminal determines the execution result of this loop closing / closing operation based on the loop breaking action signal, the local line current signal, and the local switch position signal.

2. The method according to claim 1, characterized in that, The master station sends preset commands to the liaison switch terminal and the sectional switch terminal. After the liaison switch terminal and the sectional switch terminal return preset success signals, the master station sends a loop-opening / closing execution command to the liaison switch terminal, including: The main station collects the voltage phase angles on both sides of the interconnection switch terminal, calculates the phase angle difference between the two sides based on the voltage phase angles on both sides of the interconnection switch terminal, and obtains the current phase angle difference value. The target unlooping segmented switch terminal is determined from multiple segmented switch terminals on the feeder based on the current phase angle difference. The identifier of the target loop-breaking segment switch terminal and the identifier of the communication switch terminal are combined to generate a preset command, and the preset command is sent to the communication switch terminal and the target loop-breaking segment switch terminal. After both the communication switch terminal and the target unlooping segment switch terminal return a preset success signal, the master station sends a closing and unlooping execution command to the communication switch terminal.

3. The method according to claim 2, characterized in that, The step of determining the target loop-breaking segmented switch terminal from multiple segmented switch terminals on the feeder based on the current phase angle difference includes: In response to the current phase angle difference exceeding the first phase angle difference threshold pre-configured in the master station, the first sectionalizing switch terminal located at the substation side of the feeder is identified as the target loop-breaking sectionalizing switch terminal. In response to the current phase angle difference not exceeding the first phase angle difference threshold and exceeding the second phase angle difference threshold pre-configured in the master station, the intermediate sectionalizing switch terminal located on the feeder between the first sectionalizing switch terminal and the connecting switch terminal side is determined as the target loop-breaking sectionalizing switch terminal; In response to the current phase angle difference not exceeding the second phase angle difference threshold, the end segment switch terminal located on the tie switch terminal side of the feeder is identified as the target loop-breaking segment switch terminal.

4. The method according to claim 2, characterized in that, The step of combining the identifier of the target loop-breaking segment switch terminal with the identifier of the communication switch terminal to generate a preset instruction includes: Retrieve the location identifier of the target unloop segment switch terminal and the location identifier of the interconnection switch terminal; Based on the loop impedance between the target loop-breaking segment switch terminal and the tie switch terminal and the current phase angle difference, calculate the phase angle difference safety threshold corresponding to the target loop-breaking segment switch terminal; The communication delay is measured through the 5G wireless communication link between the main station and the communication switch terminal, and the transmission lag time is calculated based on the communication delay. The preset instruction is generated by combining the location identifier of the target loop-breaking segment switch terminal, the location identifier of the communication switch terminal, the phase angle difference safety threshold, and the transmission lag time.

5. The method according to claim 2, characterized in that, After receiving the loop closure execution command, the communication switch terminal performs a loop closure action and sends a loop closure action signal to the segment switch terminal via 5G wireless communication in a point-to-point manner, including: After receiving the closing and closing loop execution command, the interconnecting switch terminal reads the phase angle difference safety threshold in the preset command, and collects the current voltage phase angle on both sides of the interconnecting switch terminal to calculate the real-time phase angle difference value. Based on the comparison between the real-time phase angle difference and the phase angle difference safety threshold, in response to the real-time phase angle difference not exceeding the phase angle difference safety threshold, the interconnection switch terminal performs a loop closing action; In response to the real-time phase angle difference exceeding the phase angle difference safety threshold, a phase angle difference over-limit signal is reported to the master station. After the master station sends a compensation completion signal containing the phase angle difference after voltage regulation, the contact switch terminal performs the loop closing action. After the loop closing action is completed, the communication switch terminal reads the transmission lag time in the preset instruction, performs lag compensation on the transmission time of the loop closing action signal according to the transmission lag time, and sends the loop closing action signal to the target de-loop segment switch terminal in a point-to-point manner via 5G wireless communication.

6. The method according to claim 5, characterized in that, In response to the real-time phase angle difference exceeding the phase angle difference safety threshold, the terminal reports a phase angle difference over-limit signal to the master station. After the master station sends a compensation completion signal containing the phase angle difference after voltage regulation, the terminal performs a loop-closing operation, including: The communication switch terminal reports the phase angle difference exceeding the limit signal to the master station; The master station calculates the required compensation amount based on the real-time phase angle difference and the phase angle difference safety threshold, and issues a voltage regulation command to the voltage regulation equipment on the substation side based on the required compensation amount; After the voltage regulation equipment on the substation side completes the voltage regulation, the master station re-collects the voltage phase angles on both sides of the tie switch terminal, calculates the phase angle difference after voltage regulation, confirms that the phase angle difference after voltage regulation does not exceed the phase angle difference safety threshold, incorporates the phase angle difference after voltage regulation into the compensation completion signal, and sends the compensation completion signal to the tie switch terminal. After receiving the compensation completion signal containing the phase angle difference after voltage adjustment, the contact switch terminal performs a loop closing operation.

7. The method according to claim 5, characterized in that, After the loop-closing operation is completed, the communication switch terminal reads the transmission lag time in the preset instruction, performs lag compensation on the transmission time of the loop-closing operation signal according to the transmission lag time, and sends the loop-closing operation signal to the target de-looping segment switch terminal in a point-to-point manner via 5G wireless communication, including: The communication switch terminal monitors the local switch position signal. In response to the local switch position signal changing from open to closed, it confirms that the loop closing action is completed and records the time when the local switch position signal changes from open to closed as the loop closing completion time. Read the transmission lag time from the preset instruction, and wait for a delay based on the loop completion time; After the delay period ends, the communication switch terminal sends a loop closing action signal to the target loop unblocking segment switch terminal via 5G wireless communication in a point-to-point manner.

8. The method according to claim 3, characterized in that, After receiving the loop-closing action signal, the segmented switch terminal performs a loop-breaking action according to the pairing relationship in the stored preset instructions, and returns a loop-breaking action signal to the tie switch terminal, including: The segmented switch terminal determines the corresponding target unlooping segmented switch terminal according to the pairing relationship in the preset instruction, and performs the unlooping action after receiving the loop closing action signal; After the loop-breaking action is completed, the time when the switch position signal of the target loop-breaking segment switch terminal changes from closed to open is used as the reference. The loop-breaking completion time is recorded, and the loop-breaking action signal is returned to the connecting switch terminal.

9. The method according to claim 2, characterized in that, The interconnecting switch terminal determines the execution result of this loop-closing / unclosing operation based on the loop-breaking action signal, combined with the local line current signal and the local switch position signal, including: The interconnection switch terminal receives the loop-breaking action signal returned by the target loop-breaking segment switch terminal, extracts the position identifier and loop-breaking completion time of the target loop-breaking segment switch terminal from the loop-breaking action signal, and collects the local line current signal and the local switch position signal, and records the time when the local switch position signal changes from open to closed as the loop-closing completion time. The time difference between loop merging and loop unmerging is calculated based on the loop merging completion time and the loop unmerging completion time. The time difference between loop merging and loop unmerging is then compared with a preset synchronization time window pre-configured in the master station to obtain the execution result of this loop merging and loop unmerging operation.

10. The method according to claim 9, characterized in that, The step of calculating the loop merging and unmerging time difference based on the loop merging completion time and the loop unmerging completion time, comparing the loop merging and unmerging time difference with a preset synchronization time window pre-configured in the master station, and obtaining the execution result of this loop merging and unmerging operation includes: The location identifier of the target loop-breaking section switch terminal is compared with the location identifier of the target loop-breaking section switch terminal in the preset instruction. Combined with the local line current signal, the local switch position signal and the loop-breaking time difference, the verification results are determined. If all verification results are passed, the loop merging and unmerging operation is deemed to have been successfully executed, and a successful loop merging and unmerging signal is reported to the master station.

11. The method according to claim 10, characterized in that, The response, upon successful completion of all verifications, determines that the ring merging and unmerging operation was executed successfully and reports a ring merging and unmerging success signal to the master station, including: In response to the following reasons: the local line current signal does not change from zero to positive; the location identifier of the target loop-breaking section switch terminal is inconsistent with the location identifier of the target loop-breaking section switch terminal in the preset instruction; the loop-closing time difference exceeds the preset synchronization time window; the tie switch terminal receives a loop-breaking failure signal returned by the target loop-breaking section switch terminal; or the local line current signal reaches the backup protection setting value pre-configured in the tie switch terminal, the loop-closing operation is determined to have failed, and a loop-closing failure signal is reported to the master station.

12. The method according to claim 2, characterized in that, Also includes: If the liaison switch terminal does not receive the loop-breaking action signal returned by the target loop-breaking section switch terminal within a preset time window configured in the liaison switch terminal, the liaison switch terminal performs a tripping action and blocks the closing, and reports a communication timeout failure signal on the liaison switch side to the master station. In response to the liaison switch terminal receiving the loop-breaking failure signal returned by the target loop-breaking section switch terminal, the liaison switch terminal performs a tripping action and blocks the closing action, and reports the section switch loop-breaking failure signal to the master station. In response to the local line current signal reaching the backup protection setting pre-configured in the tie switch terminal, the tie switch terminal triggers protection tripping and operates before the station switch, and reports a backup protection operation failure signal to the master station.

13. A distribution network fast loop-closing and unclosing device based on 5G communication, employing the distribution network fast loop-closing and unclosing control method based on 5G communication as described in any one of claims 1 to 12, characterized in that, include: The preset module is used by the master station to send preset instructions to the liaison switch terminal and the sectional switch terminal. After the liaison switch terminal and the sectional switch terminal return the preset success signal, the master station sends the loop-opening and closing execution instruction to the liaison switch terminal. The loop closing module is used to execute the loop closing action after the communication switch terminal receives the loop closing and unclosing execution command, and to send the loop closing action signal to the segment switch terminal in a point-to-point manner via 5G wireless communication. The loop-breaking module is used to execute a loop-breaking action according to the pairing relationship in the stored preset instructions after the segmented switch terminal receives the loop-closing action signal, and return a loop-breaking action signal to the interconnection switch terminal. The criterion module is used by the interconnection switch terminal to determine the execution result of the current loop closing / closing operation based on the loop closing action signal combined with the local line current signal and the local switch position signal.

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