Method for overhauling power line of hydraulic power plant

Abstract

The invention discloses a hydraulic power plant electric power line maintenance method, and belongs to the technical field of hydraulic power plant line management, and the method comprises the steps: responding to a received power failure scheduling command, after a power failure scheduling preset condition is satisfied, issuing a disconnection instruction to line switches one by one, and when all line switches are disconnected, converting the line switches into a hot standby state; after a preset condition that the line switch is switched to cold standby is met, issuing an opening instruction to the disconnecting links corresponding to the line one by one, and when all the disconnecting links are switched equally, switching the line switch to a cold standby state; and after the preset condition for switching the line to overhaul is met, issuing a closing instruction to the overhaul ground knife of the line one by one, and switching the line to an overhaul state. The 500kV line power-off maintenance device can automatically, quickly and safely complete 500kV line power-off maintenance.

Description

Technical Field

[0001] The present application belongs to the technical field of hydropower plant line management, and in particular to a method for inspecting and repairing power lines in a hydropower plant. Background Art

[0002] At present, the operation of 500kV lines in hydropower plants mostly adopts remote monitoring and cooperation of on-site operators. Each operation content needs to be confirmed on-site and remotely that the equipment status is satisfied before the next one can be executed. Each operation step requires on-site inspection and verification by the operation duty officer. In addition, the switching operation content is large and the process is complicated, and the operation efficiency is difficult to improve. At the same time, the risk of misoperation increases due to the multi-level transmission of coordinated information. If a misoperation occurs, it will have an extremely adverse impact on the stable operation of the power system and cannot meet the requirements of efficient dispatching and operation management. Summary of the invention

[0003] The purpose of this application is to provide a method for repairing power lines in a hydropower plant in order to overcome the defects of the prior art, so as to realize automatic, rapid and safe completion of power outage repairs in the line.

[0004] The purpose of this application is achieved through the following technical solutions:

[0005] A method for inspecting and repairing power lines in a hydropower plant, the method comprising:

[0006] In response to the received power outage dispatch command, after the preset conditions of the power outage dispatch are met, disconnection instructions are issued to the line switches one by one. When all the line switches are disconnected, the line switches are switched to hot standby state;

[0007] After the preset conditions for the line switch to switch to cold standby are met, an opening command is issued to the corresponding switches of the line one by one. When all the switches are evenly opened, the line switch switches to cold standby state;

[0008] After the preset conditions for the line to be switched to maintenance are met, closing commands are issued to the maintenance ground switches of the line one by one, and the line is switched to maintenance status.

[0009] Furthermore, the method further comprises:

[0010] When the dispatch command is received, the power outage dispatch command is reviewed and confirmed.

[0011] Furthermore, the method further comprises:

[0012] When disconnecting the line switch, opening the knife switch, and closing the maintenance ground knife, if any action exceeds the preset time, an alarm will be triggered and the maintenance process will be terminated.

[0013] Furthermore, the method further comprises:

[0014] When the conditions are met that the line switch on the opposite side has no pressure, the switch opening position action is compliant, and the line has no pressure, the line switch is successfully transferred to the hot standby state.

[0015] Furthermore, the method comprises:

[0016] By collecting the status parameters of the line switch, the corresponding knife switch and the maintenance ground knife, it is determined whether the corresponding action is successfully executed.

[0017] Furthermore, the method comprises:

[0018] The local control unit collects status parameters and determines whether the corresponding action is successfully executed.

[0019] The beneficial effects of this application are:

[0020] This application uses the status of a specific location node as the start condition of the process, and can realize the automatic transfer of the 500kV line of the hydropower plant to the maintenance state without manual supervision, effectively avoiding equipment damage and accidents caused by omissions in manual supervision. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a flowchart of the method for overhauling the power lines of a hydropower plant in this application;

[0022] Figure 2 It is a flowchart of a method for repairing power lines in a hydropower plant provided in an embodiment of the present application. DETAILED DESCRIPTION

[0023] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0024] Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of this application.

[0025] In the existing hydropower plant line management method, each operation content must be confirmed on-site and remotely to ensure that the equipment status is met before the next item can be executed. Each operation step requires on-site inspection and verification by the operator on duty. In addition, the switching operation content is large and the process is complicated, and the operation efficiency is difficult to improve. At the same time, the risk of misoperation increases due to the multi-level transmission of coordinated information. If a misoperation occurs, it will have an extremely adverse impact on the stable operation of the power system and cannot meet the requirements of efficient dispatching and operation management.

[0026] In order to solve the above technical problems, the following embodiments of the hydropower plant power line maintenance method of the present application are proposed.

[0027] This embodiment designs a set of special power outage and switching operation sequence control processes in the hydropower plant computer monitoring system program, and starts the 500kV line automatic power outage and judgment process with one button through the computer monitoring system, so as to achieve the purpose of automatically, quickly and safely completing the 500kV line power outage maintenance.

[0028] Reference Figure 1 ,like Figure 1 The figure is a flowchart of the method for maintenance of power lines in a hydropower plant of the present application, which method specifically comprises the following steps:

[0029] Step 1: In response to the received power outage dispatch command, after the preset conditions of the power outage dispatch are met, disconnection instructions are issued to the line switches one by one. When all the line switches are disconnected, the line switches are switched to hot standby state.

[0030] Step 2: After the preset conditions for the line switch to switch to cold standby are met, an opening command is issued to the corresponding switches of the line one by one. When all the switches are evenly opened, the line switch switches to cold standby state.

[0031] Step 3: After the preset conditions for the line to be switched to maintenance are met, a closing command is issued to the maintenance ground switches of the line one by one, and the line is switched to maintenance status.

[0032] The process designed in the monitoring program can automatically determine whether the starting conditions of the current process are met through the parameters of the 500kV line switch position node state, the corresponding knife switch position node state and the corresponding ground switch position node state, thereby automatically realizing the conversion of the line state.

[0033] This embodiment streamlines the traditional step-by-step operation procedures for 500kV line power outage maintenance, implements process flow control through a computer monitoring system, reduces the amount of operations and operational risks for operating personnel, and improves the intelligence and automation level of the hydropower station.

[0034] Since traditional manual operation can directly determine on-site whether the status of each location node meets the standard, but computer programs cannot automatically determine it, this application also proposes a method for automatically determining the status of a device by collecting multiple signals.

[0035] The opening of the switch is judged by the following conditions: ① the status of the knife switches on both sides of the switch; ② the three-phase voltage sampling value of the switch, ③ the three-phase current sampling value of the switch; ④ the remote control of the switch is ready.

[0036] The opening of the knife switch is judged by the following conditions: ① the opening and closing status of the switch; ② the three-phase voltage sampling value of the knife switch; ③ the three-phase current sampling value of the knife switch; ④ the remote control of the knife switch is ready; ⑤ the three-phase mechanical micro-switch stroke of the knife switch is in place at the same time.

[0037] The closing of the earth switch is determined by the following conditions: ① The line is powered off and there is no voltage on the three phases; ② The line switch is in the open state; ③ The line knife switch is in the open state; ④ When the earth switch is closed, the three-phase travel switches are in place at the same time.

[0038] This embodiment also provides a specific application example. Figure 2 ,like Figure 2 Shown is a flowchart of a method for repairing power lines in a hydropower plant provided in an embodiment of the present application.

[0039] After receiving the line maintenance dispatch command issued by the upper end, the command is first reviewed and confirmed. Since the execution process designed in the embodiment of the present application is part of the monitoring program, the monitoring program has other executable operations, and the review and confirmation command type can avoid the adverse effects of erroneous operations on the stable operation of the power system.

[0040] After confirming that the dispatch command is correct, it is also necessary to determine whether the line maintenance pressure plate is in operation and whether the line power outage conditions are met. There are the following points: ① The switch opening conditions are met; ② The knife switch opening conditions are met; ③ The ground knife closing conditions are met.

[0041] And the conditions for switch remote control: ① The switch remote control mode is put into use; ② The switch control power supply is normal; ③ The switch motor is normal; ④ The intelligent control of the switch control cabinet is normal. After the above conditions are prepared, confirm the dispatch order and start the operation to disconnect the line switch. The line switches of the 500kV line of the hydropower plant include the outgoing line switches and the 1-N middle switches. They need to be disconnected one by one, and when disconnecting each switch, monitor the duration of the disconnection action. When the disconnection time exceeds the time limit, it indicates that there is a fault in the line, and an alarm needs to be issued to notify the staff to carry out inspection and maintenance.

[0042] When the outgoing line switch and all the middle switches are disconnected, it is further judged whether the countermeasures are met, that the line switch has no voltage, whether the switch opening position action is in place, and whether the 500kV line has no pressure. After all of these are confirmed, the line switch hot standby action is successfully executed.

[0043] Next, the line switch is switched to cold standby mode. First, the line switching conditions need to be determined: ① The switch is closed; ② Switches 1 and 2 are closed; ③ The switch control power supply is normal; ④ The switch circuit breaker energy storage is normal; ⑤ The switch is in normal remote control state. The remote control of the switch is divided into conditions: ① The remote control mode of the switch is put into operation; ② The control power supply of the switch is normal; ③ The motor of the switch is normal; ④ The intelligent control of the switch control cabinet is normal. The above conditions are ready, and after confirming the dispatch order, the command to open the switch is issued. The switch of the 500kV line of the hydropower plant corresponds to the line switch. The outgoing line switch includes the outgoing line switch No. 1 switch and the outgoing line switch No. 2 switch. The No. 1 middle switch includes the middle switch No. 1 switch and the middle switch No. 2 switch, and so on. Each line switch corresponds to two switches.

[0044] Similarly, when each switch is opened, the duration of the disconnection action is monitored. When the disconnection time exceeds the limit, it indicates that there is a fault in the line and an alarm needs to be issued to notify the staff to carry out inspection and maintenance.

[0045] When all the switches are opened, the line switches to cold standby mode successfully.

[0046] Finally, the 500kV line of the hydropower plant is transferred for maintenance. The conditions that need to be judged include the line maintenance conditions: ① The switch opening action is normal; ② The knife switch opening action is normal; ③ The three-phase line has no voltage; ④ The three-phase line current is zero; ⑤ The grounding knife switch is remotely controlled; ⑥ The grounding knife switch control power supply is normal; ⑦ The grounding knife switch motor is normal. After the above conditions are met, check whether the knife switch opening position action is executed in place, and whether the grounding knife switch remote control is ready. After all conditions are met, issue the grounding knife closing command.

[0047] The line maintenance ground switch includes the outgoing line maintenance ground switch and the line maintenance ground switch. When the outgoing line maintenance ground switch and the line maintenance ground switch are closed in sequence, the 500kV line of the hydropower plant is transferred to the maintenance state.

[0048] Similarly, when the closing action of any earth switch exceeds the preset time requirement, it indicates that there is a fault in the line and an alarm needs to be issued to notify the staff to carry out inspection and maintenance.

[0049] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A method for inspecting and repairing power lines in a hydropower plant, characterized in that: The method comprises: In response to the received power outage dispatch command, after the preset conditions of the power outage dispatch are met, disconnection instructions are issued to the line switches one by one. When all the line switches are disconnected, the line switches are switched to hot standby state; After the preset conditions for the line switch to switch to cold standby are met, an opening command is issued to the corresponding switches of the line one by one. When all the switches are evenly opened, the line switch switches to cold standby state; After the preset conditions for the line to be switched to maintenance are met, closing commands are issued to the maintenance ground switches of the line one by one, and the line is switched to maintenance status.

2. The method for repairing power lines in a hydropower plant according to claim 1, characterized in that: The method further comprises: When the dispatch command is received, the power outage dispatch command is reviewed and confirmed.

3. The method for repairing power lines in a hydropower plant according to claim 1, characterized in that: The method further comprises: When disconnecting the line switch, opening the knife switch, and closing the maintenance ground knife, if any action exceeds the preset time, an alarm will be triggered and the maintenance process will be terminated.

4. The method for repairing power lines in a hydropower plant according to claim 1, characterized in that: The method further comprises: When the conditions are met that the line switch on the opposite side has no pressure, the switch opening position action is compliant, and the line has no pressure, the line switch is successfully transferred to the hot standby state.

5. The method for repairing power lines in a hydropower plant according to claim 1, characterized in that: The method comprises: By collecting the status parameters of the line switch, the corresponding knife switch and the maintenance ground knife, it is determined whether the corresponding action is successfully executed.

6. The method for repairing power lines in a hydropower plant according to claim 5, characterized in that: The method comprises: The local control unit collects status parameters and determines whether the corresponding action is successfully executed.

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