Intelligent operation method applied to power station electrical equipment unbackup

Abstract

The invention provides an intelligent operation method applied to hydropower station electrical equipment unbackup. The intelligent operation method comprises the steps that 1, a monitoring system issues an order to check whether operation conditions are met or not; 2, executing generator-transformer group outlet switch-to-overhaul and transformer neutral point grounding knife-switch power-off operation; 3, judging whether a generator rotor insulation test condition is met or not; 4, performing insulation measurement operation on the generator rotor; 5, executing preparation operation related to insulation measurement of the generator stator, and judging whether insulation measurement conditions of the generator stator are met or not; 6, performing insulation measurement operation on the generator stator; and 7, generator auxiliary equipment and related electrical equipment are unprepared. Equipment operation such as various switches, disconnecting links, equipment grounding and protection connecting piece breaking in the generator stator and rotor insulation measuring and electrical equipment unpreparing process is executed in a monitoring system, the operation time is shortened, the operation intensity is reduced, the whole operation process can be ensured to be accurate, the safety production management level of a power plant is improved, the operation and maintenance efficiency of the power plant is improved, and the safety and reliability of the power plant are improved. And the development of the intelligent power station is greatly promoted.

Description

Technical Field

[0001] The present invention relates to the technical field of hydro-generator control, and in particular to an intelligent operation method applied to the disconnection of electrical equipment in a hydropower station. Background Art

[0002] Hydropower station generators are core equipment in hydropower plants. Their safe and stable operation is directly related to the safety and efficiency of the power station. Therefore, planned maintenance can improve equipment reliability and promptly detect potential equipment failures. Before maintenance, generators must undergo stator and rotor insulation testing and electrical equipment de-equipment. Traditional operations are typically performed manually by operators, with multiple steps, a long time, and low efficiency. The status of many devices must be manually verified, and there are numerous operational lockouts and precautions. Manual operation is time-consuming and inefficient. If an operational lockout is encountered during operation, it is difficult to find a solution quickly, which is not conducive to improving the operation and maintenance level of the power station. Therefore, an intelligent operation method for stator and rotor insulation testing and electrical equipment de-equipment of hydropower station generators is proposed, which is of great significance for improving the operational efficiency and safety of hydropower stations. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide an intelligent operation method for the de-equipment of electrical equipment in hydropower stations, which shortens the operation time, reduces the intensity of operators, ensures the accuracy of the entire operation process, improves the safety production management level of power plants, and improves the operation and maintenance efficiency of power stations.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: The intelligent operation method for dismantling electrical equipment in a hydropower station is applied. The operation steps of the hydropower station generator set are as follows: Step 1: When the hydropower station receives a dispatching instruction to release electrical equipment, the monitoring system issues a command to check whether the operating conditions are met. If the conditions are met, the next step is executed; otherwise, the process is exited and an alarm is issued. Step 2: The monitoring system executes the "prohibit start-up" command for the unit and exits the shutdown software of the hydro-generator unit. It also performs the maintenance operation of the generator-transformer unit output switch and the transformer neutral point earth switch power-off operation. After the execution is completed, the next step is carried out. Otherwise, the process is exited and an alarm is issued. Step 3. Perform relevant preparatory operations for generator rotor insulation measurement and determine whether the generator rotor insulation measurement conditions are met; if the conditions are met, proceed to the next step; otherwise, exit the process and issue an alarm; Step 4: Measure the insulation of the generator rotor. If the insulation is qualified, proceed to the next step. Otherwise, exit the process and issue an alarm. Step 5. Perform relevant preparation operations for generator stator insulation measurement and determine whether the conditions for generator stator insulation measurement are met; if the conditions are met, proceed to the next step; otherwise, exit the process and issue an alarm; Step 6: Measure the insulation of the generator stator. If the insulation is qualified, proceed to the next step. Otherwise, exit the process and issue an alarm. Step 7: De-equip the generator auxiliary equipment and related electrical equipment. The process ends after the operation is completed, otherwise the process will exit and an alarm will be issued.

[0005] In Step 1 above, check whether the operating conditions are met, including: 1) The unit has been shut down; 2) The guide vanes of the unit are fully closed and the locking spindles are engaged; 3) The generator-transformer group outlet switch has been disconnected; 4) The generator-transformer group outlet isolation switch has been opened; 5) No one is working in the rotor circuit and slip ring chamber; 6) The maintenance work orders for the rotor circuit and slip ring chamber have been collected / cancelled; 7) The unit side grounding switch has been disconnected; 8) No one is working in the unit wind tunnel, excitation transformer, and neutral point grounding transformer; 9) The maintenance work orders for the stator circuit and generator wind tunnel have been collected / cancelled; 10) The generator outlet switch has been disconnected; 11) The generator outlet isolation switch has been opened. All of the above conditions 1-11 must be met to meet the conditions for electrical de-energization operation of the hydropower station.

[0006] The function of exiting the shutdown soft link related to the hydro-generator set in the above Step 2 is to start the shutdown process of the corresponding unit by exiting the shutdown soft link. Various action signals involving the unit shutdown include: 1. Class I mechanical accident; 2. Electrical accident; 3. Class II mechanical accident. The shutdown process can be started by triggering any one of the three types of action signals involving the unit shutdown.

[0007] The above-mentioned first-class mechanical accidents specifically include: 1. Shear pin shearing; 2. Mechanical overspeed; 3. Electrical overspeed; 4. Rapid door sliding down to the accident position; 5. Speed ​​governor accident low oil level; 6. Speed ​​governor accident low oil pressure; 7. Flooding plant sensor activation. Any of the 7 mechanical accidents will trigger a first-class mechanical accident. The shear pin shearing can be replaced by the following judgment formula: (Unit speed 1>105%×rated speed or unit speed 2>105%×rated speed) & shear pin shearing action 5s; unit speed 1 is measured by PT, unit speed 2 is measured by speed measuring device; Mechanical overspeed can be replaced by the following judgment formula: Mechanical overspeed action (speed>115% action); the speed is one of unit speed 1 and unit speed 2; Electrical overspeed can be replaced by the following judgment formula: (Unit speed 1>150%×rated speed or unit speed 2>150%×rated speed or governor speed>150% switching action) & governor speed>115% switching action; The following judgment formula can be used to replace the rapid door sliding down to the accident position: The rapid door slides down to the emergency position and the simulated opening value of the water inlet gate is less than 90% of the maximum opening value of the inlet gate; The governor accident low oil level can be replaced by the following judgment formula: The governor accident low oil level switch operates for 45 seconds, the unit is not in the shutdown state, the unit speed is greater than 10% × rated speed, and the guide vane is not in the no-load position; The governor accident low oil pressure can be replaced by the following judgment formula: The governor accident low oil pressure switch operates for 45 seconds, the unit is not in the shutdown state, the unit speed is greater than 10% × rated speed, and the guide vane is not in the no-load position; The above-mentioned electrical accidents specifically include: (Unit is in no-load state or grid-connected state) & speed > 10% × rated speed & ((A set protection total trip signal is activated & A set protection trip signal is activated) or (B set protection total trip signal is activated & B set protection trip signal is activated)); The above-mentioned second category mechanical accidents specifically include: 1) Major speed governor failure; 2) Speed ​​governor startup failure; 3) Unit overspeed; 4) Hydraulic system low pressure triggering; 5) Hydraulic system power failure; 6) Water generator backup protection triggering; 7) Emergency stop button triggering; 8) Spindle seal water source midsection; 9) Pure water system failure; 10) Protective device locked; 11) Low water flow; 12) Low cooling water flow of upper oil cooler; 13) Low cooling water flow of thrust / lower oil cooler; Any of the 13 mechanical accidents will trigger a Class II mechanical accident. The water turbine backup protection actions include thrust bearing temperature too high, lower guide bearing temperature too high, upper guide bearing temperature too high and water guide bearing temperature too high. If any one of the signals is triggered, it will be considered as the water turbine backup protection action.

[0008] The above-mentioned Step 2, in which the generator-transformer group outlet switch is turned on for maintenance, includes: pushing up the transformer side grounding switch and the bus side grounding switch; The transformer neutral point grounding knife power-off operation includes: switching the neutral point grounding knife switch control mode on the high-voltage side of the transformer to "local ground" and disconnecting the operating power supply.

[0009] In Step 3 above, the relevant preparations for generator rotor insulation measurement are performed, including: 1) Turn the AC power switch of the electrical braking circuit to the "maintenance" position; 2) Disconnect the failure protection link of the generator group; 3) Disconnect the injection-type rotor single-point grounding protection link; 4) Disconnect the ping-pong type rotor single-point grounding protection link; 5) Disconnect the power switch of the rotor grounding device; 6) Disconnect the AC demagnetization switch of the excitation system; 7) Disconnect the DC demagnetization switch of the excitation system; 8) Disconnect the excitation system excitation power switch; 9) Disconnect the excitation system excitation power signal fuse; 10) Disconnect the rotor measurement fuse; 11) Disconnect the rotor single-point grounding and demagnetization circuit fuses; 12) Disconnect the ping-pong type rotor grounding protection fuse; 13) Check that no one is working in the rotor circuit and slip ring chamber. After completing all the above operations in the order of 1-13, the generator rotor insulation measurement conditions are met. Turning the AC power switch of the electric brake circuit to the "maintenance" position can prevent power from entering the rotor through the electric brake circuit; Exiting the relevant protection link during operations 2-4 of the generator rotor insulation measurement preparation process can prevent grounding protection from being activated during stator insulation measurement, and prevent failure protection from affecting other equipment.

[0010] The generator rotor insulation measurement operation in Step 4 above specifically includes: 1) Check that the rotor insulation meter and its wiring are intact and functioning properly; 2) Verify that there is no voltage in the unit rotor circuit; 3) Measure the generator rotor insulation; 4) Check that the generator rotor insulation is qualified; 5) Discharge the generator rotor circuit to ground. If all of the above are met, the generator rotor insulation measurement operation is considered complete; The above-mentioned rotor insulation measuring meter is connected to the rotor circuit through switch control and incoming main power supply control.

[0011] In Step 5 above, the generator stator insulation test preparation operations are performed, including: 1) Check that the low-voltage side switch of the plant high-voltage transformer is disconnected; 2) Check that the AC power switch of the electrical brake circuit is in the "maintenance" position; 3) Check that the related failure protection link of the generator-transformer group is disconnected; 4) Disconnect the stator grounding protection link of the generator; 5) Disconnect the generator electric brake open circuit function link; 6) Disconnect the stator grounding protection power switch; 7) Check that the AC de-excitation switch of the excitation system is disconnected; 8) Check that the DC de-excitation switch of the excitation system is disconnected; 9) Check that the excitation power switch of the excitation system is disconnected; 10) Check that the excitation power signal fuse of the excitation system is removed; 11) Check that the generator electrical brake short-circuit switch is disconnected; 12) Check that the generator electrical brake short-circuit circuit breaker is disconnected. The grounding knife switch has been opened; 13) Push up the generator electrical brake short-circuit grounding knife switch and close the generator electrical brake short-circuit switch; 14) Disconnect the generator end PT secondary switch; 15) Disconnect the neutral point grounding wire of the generator PT primary side; 16) Disconnect the generator electrical brake short-circuit switch and pull up the generator electrical brake short-circuit grounding knife switch; 17) Pull out the generator neutral point grounding knife switch; 18) Check that the generator pure water system is operating normally; 19) Disconnect the grounding wire of the generator pure water cooling ring pipe; 20) Use a multimeter to measure the insulation resistance of the ring pipe to ground, the value should be greater than 10kΩ; After all the above operations are completed in the order of 1-20, the generator stator insulation measurement conditions are met.

[0012] The generator stator insulation measurement operation in Step 6 above specifically includes: 1) Check that the insulation resistance measuring meter and its wiring of the water-cooled generator are intact and functioning properly; 2) Switch the voltage switch of the insulation resistance measuring meter of the water-cooled generator to "2500V" and measure the stator insulation; 3) Record the stator insulation measurement meter's value. 、 、 value, and check whether the generator stator insulation is qualified; 4) Turn off the stator insulation measuring meter; 5) Discharge the stator wire rods and pure water ring pipe to the ground, and re-lead the ground wire of the generator pure water cooling ring pipe; If all the above operations are met, the generator stator insulation measurement operation is completed.

[0013] The above-mentioned Step 7 for disconnecting the auxiliary equipment and related electrical equipment of the generator specifically includes: 1) checking that there is no voltage at the neutral point grounding switch of the generator, and short-circuiting the dynamic and static contacts to ground respectively; 2) engaging the mechanical brake damper, switching the control mode to "manual", and closing the mechanical brake exhaust valve; 3) stopping the pure water system and disconnecting the power supply; 4) checking that there is no voltage on the high and low voltage sides of the excitation transformer, and performing a grounding operation on the high and low voltage three phases of the excitation transformer; 5) pushing up the generator electrical brake short-circuit grounding switch, closing the generator electrical brake short-circuit switch, switching the control mode to "manual", and disconnecting the power supply; 6) checking that the generator outlet switch has been disconnected, pushing up the generator outlet isolation switch, and disconnecting the power supply; 7) checking that there is no voltage on the high and low voltage sides of the plant high voltage transformer, and performing a grounding operation on the high and low voltage three phases of the plant high voltage transformer. The above operations are completed in the order of 1-7 to complete the disconnection operation process.

[0014] The intelligent operation method mentioned in the present invention for the release of electrical equipment in hydropower stations makes full use of program condition judgment and scientific and reasonable processes to execute: insulation measurement of generator stators and rotors, various switches, knife switches, equipment grounding, disconnection of protective connectors and other equipment operations during the release of electrical equipment. It not only shortens the operation time and reduces the intensity of operators, but also ensures that the entire operation process is accurate, helps to improve the level of safe production management of power plants, improves the operation and maintenance efficiency of power stations, and greatly promotes the development of smart power stations. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention will be further described below with reference to the accompanying drawings and examples: Figure 1 This is a flow chart of the intelligent operation method applied to the electrical equipment of a hydropower station according to the present invention; Figure 2 This is the wiring diagram of the equipment column of the hydropower station unit of the present invention; Figure 3 This is a schematic diagram of the conditions that need to be met for the electrical equipment of a hydropower station in the present invention; Figure 4 Schematic diagram of the conditions that need to be met for insulation measurement of the generator rotor of the present invention; Figure 5 Schematic diagram of the conditions that need to be met for insulation measurement of the generator stator of the present invention; Figure 6 This is a wiring diagram of a megohmmeter for measuring insulation resistance of a water-cooled generator according to the present invention; Figure 7 This is a working principle diagram of the megohmmeter for measuring the insulation resistance of a water-cooled generator according to the present invention; Figure 8 This is a schematic diagram of the conditions that need to be met for the unit to idle; Figure 9 This is a schematic diagram of the conditions that need to be met when the unit is no-load; Figure 10 Schematic diagram of the conditions that need to be met for the unit to be connected to the grid; Figure 11 This is a schematic diagram of the generator rotor insulation measurement circuit.

[0016] In the figure: generator neutral point grounding transformer 1; generator neutral point grounding switch 2; generator 3; electrical brake short-circuit switch 4; electrical brake short-circuit grounding switch 5; excitation transformer 6; unit-side grounding switch 7; transformer-side grounding switch 8; generator outlet switch 9; generator outlet isolation switch 10; plant high-voltage transformer 11; transformer 12; transformer high-voltage side neutral point grounding switch 13; transformer-side grounding switch 14; busbar-side grounding switch 15; generator-transformer group outlet switch 16; generator-transformer group outlet isolation switch 17; AC de-excitation switch 18; DC de-excitation switch 19. DETAILED DESCRIPTION

[0017] The technical solution of the present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0018] The intelligent operation method for dismantling electrical equipment in a hydropower station is applied. The operation steps of the hydropower station generator set are as follows: Step 1: When the hydropower station receives a dispatching instruction to release electrical equipment, the monitoring system issues a command to check whether the operating conditions are met. If the conditions are met, the next step is executed; otherwise, the process is exited and an alarm is issued. Step 2: The monitoring system executes the "prohibit start-up" command for the unit and exits the shutdown software of the hydro-generator unit. It also performs the maintenance operation of the generator-transformer unit output switch and the transformer neutral point earth switch power-off operation. After the execution is completed, the next step is carried out. Otherwise, the process is exited and an alarm is issued. Step 3. Perform relevant preparatory operations for generator rotor insulation measurement and determine whether the generator rotor insulation measurement conditions are met; if the conditions are met, proceed to the next step; otherwise, exit the process and issue an alarm; Step 4: Measure the insulation of the generator rotor. If the insulation is qualified, proceed to the next step. Otherwise, exit the process and issue an alarm. Step 5. Perform relevant preparation operations for generator stator insulation measurement and determine whether the conditions for generator stator insulation measurement are met; if the conditions are met, proceed to the next step; otherwise, exit the process and issue an alarm; Step 6: Measure the insulation of the generator stator. If the insulation is qualified, proceed to the next step. Otherwise, exit the process and issue an alarm. Step 7: De-equip the generator auxiliary equipment and related electrical equipment. The process ends after the operation is completed, otherwise the process will exit and an alarm will be issued.

[0019] In Step 1 above, check whether the operating conditions are met, including: 1. The unit has indeed been shut down; 2. The unit guide vanes are fully closed and the locking spindles are engaged; 3. The generator-transformer group outlet switch has indeed been disconnected; 4. The generator-transformer group outlet isolation knife switch has indeed been opened; 5. No one is working in the rotor circuit and slip ring chamber; 6. The maintenance work orders for the rotor circuit and slip ring chamber have been collected / cancelled; 7. The unit side grounding knife switch has indeed been disconnected; 8. No one is working in the unit wind tunnel, excitation transformer, and neutral point grounding transformer; 9. The maintenance work orders for the stator circuit and generator wind tunnel have been collected / cancelled; 10. The generator outlet switch 9 has been disconnected; 11. The generator outlet isolation knife switch (10) has been opened; All of the above conditions 1-11 must be met to meet the conditions for electrical de-energization operation of the hydropower station.

[0020] The function of exiting the shutdown soft link related to the hydro-generator set in the above Step 2 is to start the shutdown process of the corresponding unit by exiting the shutdown soft link. Various action signals involving the unit shutdown include: 1. Class I mechanical accident; 2. Electrical accident; 3. Class II mechanical accident. The shutdown process can be started by triggering any one of the three types of action signals involving the unit shutdown.

[0021] The above-mentioned first-class mechanical accidents specifically include: 1. Shear pin shearing; 2. Mechanical overspeed; 3. Electrical overspeed; 4. Rapid door sliding down to the accident position; 5. Speed ​​governor accident low oil level; 6. Speed ​​governor accident low oil pressure; 7. Flooding plant sensor activation. Any of the 7 mechanical accidents will trigger a first-class mechanical accident. The shear pin shearing can be replaced by the following judgment formula: (Unit speed 1>105%×rated speed or unit speed 2>105%×rated speed) & shear pin shearing action 5s; unit speed 1 is measured by PT, unit speed 2 is measured by speed measuring device; Mechanical overspeed can be replaced by the following judgment formula: Mechanical overspeed action (speed>115% action); the speed is one of unit speed 1 and unit speed 2; Electrical overspeed can be replaced by the following judgment formula: (Unit speed 1>150%×rated speed or unit speed 2>150%×rated speed or governor speed>150% switching action) & governor speed>115% switching action; The following judgment formula can be used to replace the rapid door sliding down to the accident position: The rapid door slides down to the emergency position and the simulated opening value of the water inlet gate is less than 90% of the maximum opening value of the inlet gate; The governor accident low oil level can be replaced by the following judgment formula: The governor accident low oil level switch operates for 45 seconds, the unit is not in the shutdown state, the unit speed is greater than 10% × rated speed, and the guide vane is not in the no-load position; The governor accident low oil pressure can be replaced by the following judgment formula: The governor accident low oil pressure switch operates for 45 seconds, the unit is not in the shutdown state, the unit speed is greater than 10% × rated speed, and the guide vane is not in the no-load position; like Figure 8 As shown in , the idling conditions of the unit are met, including: the cooling water system is running or the unit is started until the cooling water system operating conditions are met, the high-pressure oil system is normal, the unit water inlet gate is normal, the water machine backup protection is normal, the shear pin is normal, the speed control system is normal, the braking system is normal, the brake air damper is down, the oil pressure system is normal, the maintenance air seal is normal, the main shaft sealing system is normal, the basic startup conditions are met, the unit is not in idling state, the unit is not in no-load state, and the unit is not in grid-connected state.

[0022] like Figure 9 As shown in , the no-load conditions of the unit are met specifically including: the unit is in idling state or the start-up to idling conditions are met, the electrical protection is normal, the excitation system is normal, the ground switch state meets the start-up conditions, the basic start-up conditions are met, the unit is not in the no-load state, and the unit is not in the grid-connected state.

[0023] like Figure 10 As shown in , the conditions for unit grid connection include: the unit maintenance status mark is exited, the knife isolation status meets the startup conditions, the unit is no-load or the startup to no-load conditions are met, the circuit breaker control circuit is normal, the synchronization device is normal, the main synchronization switch is in the open state, and the basic startup conditions are met.

[0024] The above-mentioned electrical accidents specifically include: (Unit is in no-load state or grid-connected state) & speed > 10% × rated speed & ((A set protection total trip signal is activated & A set protection trip signal is activated) or (B set protection total trip signal is activated & B set protection trip signal is activated)); The above-mentioned second category mechanical accidents specifically include: 1. Major speed regulator failure; 2. Speed ​​regulator startup failure; 3. Unit overspeed; 4. Hydraulic system low pressure triggering; 5. Hydraulic system power failure; 6. Water generator backup protection triggering; 7. Emergency stop button triggering; 8. Spindle seal water source middle section; 9. Pure water system failure; 10. Protective device locked; 11. Low water flow; 12. Low cooling water flow of upper oil cooler; 13. Low cooling water flow of thrust / lower oil cooler, etc. Any of the 13 mechanical accidents will trigger a Class II mechanical accident. The water turbine backup protection actions include thrust bearing temperature too high, lower guide bearing temperature too high, upper guide bearing temperature too high and water guide bearing temperature too high. If any one of the signals is triggered, it will be considered as the water turbine backup protection action.

[0025] The above-mentioned Step 2, in which the generator-transformer group outlet switch is turned on for maintenance, includes: pushing up the transformer side grounding switch and the bus side grounding switch; The transformer neutral point grounding knife power-off operation includes: switching the neutral point grounding knife switch control mode on the high-voltage side of the transformer to "local ground" and disconnecting the operating power supply.

[0026] In Step 3 above, the relevant preparations for generator rotor insulation measurement are performed, including: 1. Turn the AC power switch of the electrical braking circuit to the "maintenance" position; 2. Disconnect the related failure protection links of the generator set; 3. Disconnect the injection-type rotor single-point grounding protection link; 4. Disconnect the ping-pong type rotor single-point grounding protection link; 5. Disconnect the power switch of the rotor grounding device; 6. Disconnect the AC demagnetization switch of the excitation system; 7. Disconnect the DC demagnetization switch 19 of the excitation system; 8. Disconnect the excitation system starting power switch; 9. Disconnect the excitation system starting power signal fuse; 10. Disconnect the rotor measurement fuse; 11. Disconnect the rotor single-point grounding and demagnetization circuit fuses; 12. Disconnect the ping-pong type rotor grounding protection fuse; 13. Check that no one is working in the rotor circuit and slip ring chamber. After completing all the above operations in the order of 1-13, the generator rotor insulation measurement conditions can be met; Turning the AC power switch of the electric brake circuit to the "maintenance" position can prevent power from entering the rotor through the electric brake circuit; Exiting the relevant protection link during operations 2-4 of the generator rotor insulation measurement preparation process can prevent grounding protection from being activated during stator insulation measurement, and prevent failure protection from affecting other equipment.

[0027] The generator rotor insulation measurement operation in Step 4 above specifically includes: 1. Check that the rotor insulation meter and its wiring are intact and functioning properly; 2. Verify that there is no voltage in the unit rotor circuit; 3. Measure the generator rotor insulation; 4. Check that the generator rotor insulation is qualified; 5. Discharge the generator rotor circuit to the ground. If all of the above are met, the generator rotor insulation measurement operation is considered complete; The above-mentioned rotor insulation measuring meter is connected to the rotor circuit through switch control and incoming main power supply control.

[0028] The specific circuit for generator rotor insulation measurement is as follows: Figure 9 As shown in FIG, Q1 is a switch, DC is the incoming main power supply, and the incoming main power supply DC controls the opening and closing of the switch Q1, thereby realizing the disconnection and connection of the generator rotor insulation measurement circuit.

[0029] In Step 5 above, the generator stator insulation test preparation operations are performed, including: 1. Check that the low-voltage side switch of the plant's high-voltage transformer is disconnected; 2. Check that the AC power switch of the electrical brake circuit is in the "maintenance" position; 3. Check that the related failure protection link of the generator-transformer group is disconnected; 4. Disconnect the stator grounding protection link of the generator; 5. Disconnect the generator electric brake open circuit function link; 6. Disconnect the stator grounding protection power switch; 7. Check that the AC de-excitation switch of the excitation system is disconnected; 8. Check that the DC de-excitation switch of the excitation system is disconnected; 9. Check that the excitation power switch of the excitation system is disconnected; 10. Check that the excitation power signal fuse of the excitation system is removed; 11. Check that the generator electrical brake short-circuit switch is disconnected; 12. Check that the generator electrical brake short-circuit circuit breaker is disconnected. The grounding knife switch has been opened; 13. Push up the generator electrical brake short-circuit grounding knife switch, and close the generator electrical brake short-circuit switch; 14. Disconnect the generator end PT secondary switch; 15. Disconnect the neutral point grounding wire of the generator PT primary side; 16. Disconnect the generator electrical brake short-circuit switch, and pull the generator electrical brake short-circuit grounding knife switch; 17. Pull the generator neutral point grounding knife switch; 18. Check that the generator pure water system is operating normally; 19. Disconnect the grounding wire of the generator pure water cooling ring pipe; 20. Use a multimeter to measure the insulation resistance of the ring pipe to the ground. The value should be greater than 10kΩ; After all the above operations are completed in the order of 1-20, the generator stator insulation measurement conditions are met.

[0030] The generator stator insulation measurement operation in Step 6 above specifically includes: 1. Check that the insulation resistance measuring meter of the water-cooled generator and its wiring are intact and functioning normally; 2. Switch the voltage switch of the insulation resistance measuring meter of the water-cooled generator to "2500V" and measure the stator insulation; 3. Record the stator insulation measurement meter's 、 、 value, and check whether the generator stator insulation is qualified; 4. Turn off the stator insulation measuring meter; 5. Discharge the stator wire rods and pure water ring pipe to the ground, and re-lead the ground wire of the generator pure water cooling ring pipe; if all the above operations are met, the generator stator insulation measurement operation is completed.

[0031] 、 、 They respectively represent the insulation resistance values ​​of the water-cooled generator measured at 15s, 30s and 60s.

[0032] The above-mentioned Step 7, the de-energizing operation of the generator auxiliary equipment and related electrical equipment, specifically includes: 1. Checking that there is no voltage at the neutral point grounding knife switch of the generator, and short-circuiting the moving and static contacts to ground respectively; 2. Engaging the mechanical brake damper, switching the control mode to "manual", and closing the mechanical brake exhaust valve; 3. Stopping the pure water system and disconnecting the power supply; 4. Checking that there is no voltage on the high and low voltage sides of the excitation transformer, and grounding the three phases of the high and low voltage sides of the excitation transformer; 5. Pushing up the generator electrical brake short-circuit grounding knife switch, closing the generator electrical brake short-circuit switch, switching the control mode to "manual", and disconnecting the power supply; 6. Checking that the generator outlet switch has been disconnected, pushing up the generator outlet isolation knife switch, and disconnecting the power supply; 7. Checking that there is no voltage on the high and low voltage sides of the plant high-voltage transformer, and grounding the three phases of the high and low voltage sides of the plant high-voltage transformer. The above operations are completed in the order of 1-7 to complete the de-energizing operation process.

[0033] Example 1: An intelligent operation method for measuring insulation of stator and rotor of hydropower station generator and disassembling electrical equipment is as follows: Figure 1 The specific steps are as follows: Step 1: When the hydropower station receives a dispatching instruction to release electrical equipment, the monitoring system issues a command to check whether the operating conditions are met. If the conditions are met, the next step is executed; otherwise, the process is exited and an alarm is issued. The main wiring diagram of the hydropower station equipment in step 1 is as shown in the attached figure. Figure 2 As shown, it specifically includes: 1 generator neutral point grounding transformer; 2 generator neutral point grounding switch; 3 generator; 4 electrical brake short-circuit switch; 5 electrical brake short-circuit grounding switch; 6 excitation transformer; 7 unit side grounding switch; 8 transformer side grounding switch; 9 generator outlet switch; 10 generator outlet isolation switch; 11 plant high-voltage transformer; 12 transformer; 13 transformer high-voltage side neutral point grounding switch; 14 transformer side grounding switch; 15 busbar side grounding switch; 16 generator-transformer group outlet switch; 17 generator-transformer group outlet isolation switch; 18 AC demagnetization switch; 19 DC demagnetization switch.

[0034] In the above step 1, when the hydropower station receives the dispatching instruction for releasing the electrical equipment, it automatically checks whether the operating conditions are met, including: 1. The unit has been shut down; 2. The guide vanes of the unit are fully closed and the lock spindles are engaged; 3. The generator-transformer group outlet switch is disconnected; 4. The generator-transformer group outlet isolation switch is opened; 5. No one is working in the rotor circuit and slip ring chamber; 6. The maintenance work order for the rotor circuit and slip ring chamber has been collected / cancelled; 7. The unit side grounding switch is disconnected; 8. No one is working in the unit wind tunnel, excitation transformer, and neutral point grounding transformer; 9. The maintenance work order for the stator circuit and generator wind tunnel has been collected / cancelled; 10. The generator outlet switch 9 is disconnected; 11. The generator outlet isolation switch 10 is opened. For details on the conditions that need to be met for the release of the electrical equipment of the hydropower station, please refer to Figure 3 shown.

[0035] Step 2: The monitoring system executes the "prohibit start-up" command for the unit, exits the shutdown software of the hydro-generator unit, performs the maintenance operation of the generator-transformer unit output switch, and disconnects the neutral point earth switch of the transformer. After the execution is completed, the next step is carried out. Otherwise, the process is exited and an alarm is issued. The function of exiting the shutdown soft link related to the hydro-turbine generator set in the above step 2 is to start the shutdown process of the corresponding unit by exiting the shutdown soft link, and various action signals involving the unit shutdown include: 1. Class I mechanical accident; 2. Electrical accident; 3. Class II mechanical accident.

[0036] The first type of mechanical accidents in step 2 above specifically include: 1. Shear pin shearing (unit speed 1 (PT measurement) > 105% or unit speed 2 (speed measuring device) speed > 105% & shear pin shearing action 5s); 2. Mechanical overspeed (mechanical overspeed action & speed > 115% action); 3. Electrical overspeed (unit speed 1 (PT measurement) > 150% or unit speed 2 (speed measuring device) > 150% or speed regulator speed > 150% switch action & speed regulator speed > 115) % switch action); 4. Rapid door slides down to the emergency position (rapid door slides down to the emergency position & the analog value of the water inlet gate opening is less than 90%); 5. Governor accident low oil level (Governor accident low oil level switch action for 45 seconds & the unit is not in the shutdown state & the unit speed is greater than 10% & the guide vane is not in the no-load position); 6. Governor accident low oil pressure (Governor accident low oil pressure switch action for 45 seconds & the unit is not in the shutdown state & the unit speed is greater than 10% & the guide vane is not in the no-load position); 7. Two sensors in the flooded plant are activated.

[0037] The electrical accidents in step 2 above specifically include: (unit status is no-load or unit status is grid-connected) & speed > 10% & ((the main trip signal of protection set A is activated & the sub-trip signal of protection set A is activated) or (the main trip signal of protection set B is activated & the sub-trip signal of protection set B is activated)).

[0038] The second type of mechanical accidents in the above step 2 specifically include: 1. Major failure of the speed regulator; 2. Failure to start the speed regulator; 3. Overspeed of the unit; 4. Hydraulic system pressure is too low; 5. Hydraulic system power failure; 6. Water machine backup protection action (thrust bearing temperature is too high, lower guide bearing temperature is too high, upper guide bearing temperature is too high, water guide bearing temperature is too high); 7. Emergency stop button action; 8. Middle section of the main shaft seal water source; 9. Pure water system failure; 10. Protection device locked; 11. Low water guide oil flow; 12. Low cooling water flow of the upper guide oil cooler; 13. Low cooling water flow of the thrust / lower guide oil cooler, etc.

[0039] The above step 2 in which the generator-transformer group outlet switch is turned on for maintenance refers to: pushing up the transformer side grounding knife switch (14) and the bus side grounding knife switch 15; the transformer neutral point grounding knife power-off operation includes: switching the control mode of the transformer high-voltage side neutral point grounding knife switch 13 to "local ground" and disconnecting the operating power supply.

[0040] Step 3: Perform relevant preparatory operations for generator rotor insulation measurement and determine whether the generator rotor insulation measurement conditions are met. If so, proceed to the next step; otherwise, exit the process and issue an alarm. In the above step 3, the relevant preparation operations for generator rotor insulation measurement are performed, which specifically include: 1. Turning the AC power switch of the electrical braking circuit to the "maintenance" position; 2. Disconnecting the related failure protection link of the transformer group; 3. Disconnecting the injection-type rotor single-point grounding protection link; 4. Disconnecting the ping-pong type rotor single-point grounding protection link; 5. Disconnecting the power switch of the rotor grounding device; 6. Disconnecting the AC demagnetization switch 18 of the excitation system; 7. Disconnecting the DC demagnetization switch 19 of the excitation system; 8. Disconnecting the excitation system starting power switch; 9. Disconnecting the excitation system starting power signal fuse; 10. Disconnecting the rotor measurement fuse; 11. Disconnecting the rotor single-point grounding and demagnetization circuit fuses; 12. Disconnecting the ping-pong type rotor grounding protection fuse; 13. Checking that no one is working in the rotor circuit and slip ring chamber. After all the above operations are completed in sequence, the generator rotor insulation measurement conditions can be met. The generator rotor insulation measurement meets the conditions as shown in the attached Figure 4 shown.

[0041] The purpose of turning the AC power switch of the electrical brake circuit to the "Inspection" position in step 3 above is to prevent power from entering the rotor through the electrical brake circuit. The purpose of removing the relevant protection link is to prevent ground fault protection from being activated during stator insulation measurement, and to prevent failure protection from affecting other equipment. Step 4: Measure the insulation of the generator rotor. If the insulation is qualified, proceed to the next step. Otherwise, exit the process and issue an alarm. The generator rotor insulation measurement operation in the above step 4 specifically includes: 1. Checking that the rotor insulation measuring meter and its wiring are intact and functioning normally; 2. Verifying that there is no voltage in the unit rotor circuit; 3. Measuring the generator rotor insulation (using a 500V megohmmeter); 4. Checking that the generator rotor insulation is qualified (the insulation resistance value must not be less than 0.5MΩ); 5. Discharging the generator rotor circuit to the ground.

[0042] In step 4 above, the rotor insulation measuring meter is connected to the rotor circuit through switch control and incoming main power supply control, and can be turned on with one button in the monitoring system to measure the generator rotor insulation; Step 5: Perform relevant preparatory operations for generator stator insulation measurement and determine whether the conditions for generator stator insulation measurement are met. If so, proceed to the next step; otherwise, exit the process and issue an alarm. In step 5 above, the relevant preparation operations for generator stator insulation measurement are performed, specifically including: 1. Check that the low-voltage side switch of the plant high-voltage transformer 11 is disconnected; 2. Check that the AC power switch of the electrical brake circuit is turned to the "maintenance" position; 3. Check that the relevant failure protection link of the generator-transformer group has been withdrawn; 4. Disconnect the generator stator grounding protection link; 5. Disconnect the generator electric brake open circuit function link; 6. Disconnect the stator grounding protection power switch; 7. Check that the AC demagnetization switch (18) of the excitation system is disconnected; 8. Check that the DC demagnetization switch 19 of the excitation system is disconnected; 9. Check that the excitation system starting power switch is disconnected; 10. Check that the excitation system starting power signal fuse is removed; 11. Check that the generator electrical brake short-circuit switch 4 is disconnected; 12. Check that the generator electrical brake short-circuit grounding knife switch 5 is opened; 13. Push up the generator electrical brake short-circuit grounding knife switch and close the generator electrical brake Short-circuit switch (or after phase separation to verify that there is no electricity on the high-voltage side of the excitation transformer, perform grounding operation on the three phases on the high-voltage side of the excitation transformer); 14. Disconnect the PT secondary switch on the generator end; 15. Disconnect the neutral point grounding wire on the primary side of the generator PT; 16. Disconnect the generator electrical brake short-circuit switch, and pull the generator electrical brake short-circuit grounding knife switch. If the three phases are grounded on the high-voltage side of the excitation transformer, perform grounding disconnection operation on the three phases on the high-voltage side of the excitation transformer; 17. Pull the neutral point grounding knife switch 2 of the generator generator; 18. Check that the pure water system of the generator is operating normally; 19. Disconnect the grounding wire of the pure water cooling ring pipe of the generator; 20. Use a multimeter to measure the insulation resistance of the ring pipe to the ground. The value should be greater than 10kΩ (if the measured insulation value is too low or close to zero, it means that the water collection ring pipe is not completely disconnected from the ground, or the insulation of the water collection ring pipe is abnormal and needs to be checked); After all the above operations are completed in sequence, the generator stator insulation measurement conditions can be met. The generator stator insulation measurement meets the conditions as shown in the attached Figure 5 shown.

[0043] Step 6: Measure the insulation of the generator stator. If the insulation is qualified, proceed to the next step. Otherwise, exit the process and issue an alarm. The generator stator insulation measurement operation in step 6 above specifically includes: 1. Check that the insulation resistance measuring megohmmeter of the water-cooled generator and its wiring are intact and functioning normally (the high-voltage wire of the insulation resistance measuring megohmmeter of the water-cooled generator is connected to the stator bar, the shielding wire is connected to the pure water cooling loop, and the ground wire is connected to the dedicated ground wire); 2. Switch the voltage switch of the insulation resistance measuring megohmmeter of the water-cooled generator to "2500V" to measure the stator insulation; 3. Record the R value of the stator insulation measuring meter. 、R 、R value, and check that the generator stator insulation is qualified (absorption ratio is R / R , not less than 1.3); 4. Turn off the stator insulation meter; 5. Discharge the stator bars and pure water ring pipe to the ground, and reconnect the generator pure water cooling ring pipe to the ground wire; In step 6 above, the generator stator insulation test operation uses a water-cooled generator insulation resistance measuring megohmmeter. The wiring diagram is shown in the attached diagram. Figure 6 As shown, C X 、R X Respectively represent the size of distributed capacitance and winding insulation resistance; R Y 、R H Indicates different branches; the external filter is only used when the water resistance is too low or the distributed capacitance of the measured load is large, making the measurement impossible. It is not necessary to connect. The principle is to use a current measurement device based on equipotential large current shielding, an equipotential follower based on an operational amplifier and a current expansion circuit to separate the interference current from the total current and absorb it, thereby eliminating the influence of the interference current on the measured current. Figure 7 As shown, the inverting input terminal of N2 is high impedance, the interference current flows through the current lead, and no current flows through the voltage line, so its input and output potentials are equal, that is, V B =V E The two input terminals of N2 are virtual short, so there is V E =V C It can be seen that through this potential follower, the potential of the input end of the current and voltage leads can follow the potential of the test input end, that is, V BC = 0, thereby completely absorbing the interference current I w1 , and ensure I w2 =0. Use resistor R1 to control the current I x By sampling, the insulation resistance of the stator winding can be obtained. 总 : Tester input current; R w1 : Equivalent water resistance between the winding and the water collection pipe; R w2 : Equivalent resistance between the water collection pipe and the base; I w1: Leakage current from winding to water collector; I w2 : Leakage current from the water pipe to the base, N1, N2: operational amplifiers; T1, T2: transistors; R1, R2: resistors; V G : Voltage output.

[0044] In step 6 above, the insulation resistance measuring megohmmeter for the water-cooled generator is connected to the stator circuit through switch control and incoming main power supply control. It can be turned on with one button in the monitoring system to measure the stator insulation of the generator. Step 7: De-equip the generator auxiliary equipment and related electrical equipment. The process ends after the operation is completed, otherwise the process will exit and an alarm will be issued; The de-equipment operation of the generator auxiliary equipment and related electrical equipment in the above step 7 specifically includes: 1. Detecting that there is no voltage at the generator neutral point grounding switch 2, and short-circuiting the moving and static contacts to ground respectively; 2. Engaging the mechanical brake damper, and switching the control mode to "manual", and closing the mechanical brake exhaust valve; 3. Stopping the pure water system and disconnecting the power supply; 4. Detecting that there is no voltage on the high and low voltage sides of the excitation transformer 6, and grounding the high and low voltage sides of the excitation transformer; 5. Pushing up the generator electrical brake short-circuit grounding switch, and closing the generator electrical brake short-circuit switch, and switching the control mode to "manual", and disconnecting the power supply; 6. Checking that the generator outlet switch 9 is disconnected, pushing up the generator outlet isolation switch 10, and disconnecting the power supply; 7. Detecting that there is no voltage on the high and low voltage sides of the plant high-voltage transformer 11, and grounding the high and low voltage sides of the plant high-voltage transformer.

Claims

1. An intelligent operation method for dismantling electrical equipment in a hydropower station, characterized in that: The operating steps of the hydropower station generator set are as follows: Step 1: When the hydropower station receives a dispatching instruction to release electrical equipment, the monitoring system issues a command to check whether the operating conditions are met. If the conditions are met, the next step is executed; otherwise, the process is exited and an alarm is issued. Step 2: The monitoring system executes the "prohibit start-up" command for the unit and exits the shutdown software of the hydro-generator unit. It also performs the maintenance operation of the generator-transformer unit output switch and the transformer neutral point grounding switch. After the execution is completed, the next step is carried out. Otherwise, the process is exited and an alarm is issued. Step 3. Perform relevant preparatory operations for generator rotor insulation measurement and determine whether the generator rotor insulation measurement conditions are met; if the conditions are met, proceed to the next step; otherwise, exit the process and issue an alarm; Step 4: Measure the insulation of the generator rotor. If the insulation is qualified, proceed to the next step. Otherwise, exit the process and issue an alarm. Step 5. Perform relevant preparation operations for generator stator insulation measurement and determine whether the conditions for generator stator insulation measurement are met; if the conditions are met, proceed to the next step; otherwise, exit the process and issue an alarm; Step 6: Measure the insulation of the generator stator. If the insulation is qualified, proceed to the next step. Otherwise, exit the process and issue an alarm. Step 7: De-equip the generator auxiliary equipment and related electrical equipment. The process ends after the operation is completed, otherwise the process will exit and an alarm will be issued.

2. According to the intelligent operation method for disconnecting electrical equipment in a hydropower station according to claim 1, the step 1 of checking whether the operating conditions are met specifically includes: 1) The unit has been shut down; 2) The unit guide vanes are fully closed and the locking spindles are engaged; 3) The generator-transformer group outlet switch has been disconnected; 4) The generator-transformer group outlet isolation switch has been opened; 5) No one is working in the rotor circuit and slip ring chamber; 6) The maintenance work orders for the rotor circuit and slip ring chamber have been collected / cancelled; 7) The unit side grounding switch has been disconnected; 8) No one is working in the unit wind tunnel, excitation transformer, and neutral point grounding transformer; 9) The maintenance work orders for the stator circuit and generator wind tunnel have been collected / cancelled; 10) The generator outlet switch (9) has been disconnected; 11) The generator outlet isolation switch (10) has been opened; All of the above conditions 1-11 must be met to meet the conditions for electrical de-energization operation of the hydropower station.

3. According to the intelligent operation method for releasing electrical equipment in a hydropower station according to claim 1, the function of exiting the shutdown soft link related to the hydro-generator set in Step 2 is: the corresponding unit shutdown process is started by locking the exit shutdown soft link, and various action signals involving unit shutdown include:

1. Class I mechanical accident; 2. Electrical accident; 3. Class II mechanical accident. The shutdown process can be started by triggering any one of the three types of action signals involving unit shutdown.

4. According to the intelligent operation method for disconnecting electrical equipment in a hydropower station as described in claim 3, the first type of mechanical accident specifically includes:

1. Shear pin shearing; 2. Mechanical overspeed; 3. Electrical overspeed; 4. Rapid door sliding down to the accident position; 5. Governor accident low oil level; 6. Governor accident low oil pressure; 7. Flooding plant sensor activation; Any of the seven mechanical accidents will trigger a first type of mechanical accident; The shear pin shearing can be replaced by the following judgment formula: (Unit speed 1>105%×rated speed or unit speed 2>105%×rated speed) & shear pin shearing action 5s; unit speed 1 is measured by PT, unit speed 2 is measured by speed measuring device; Mechanical overspeed can be replaced by the following judgment formula: Mechanical overspeed action (speed>115% action); the speed is one of unit speed 1 and unit speed 2; Electrical overspeed can be replaced by the following judgment formula: (Unit speed 1>150%×rated speed or unit speed 2>150%×rated speed or governor speed>150% switching action) & governor speed>115% switching action; The following judgment formula can be used to replace the rapid door sliding down to the accident position: The rapid door slides down to the emergency position and the simulated opening value of the water inlet gate is less than 90% of the maximum opening value of the inlet gate; The governor accident low oil level can be replaced by the following judgment formula: The governor accident low oil level switch operates for 45 seconds, the unit is not in the shutdown state, the unit speed is greater than 10% × rated speed, and the guide vane is not in the no-load position; The governor accident low oil pressure can be replaced by the following judgment formula: The governor accident low oil pressure switch operates for 45 seconds, the unit is not in the shutdown state, the unit speed is greater than 10% × rated speed, and the guide vane is not in the no-load position; The electrical accidents specifically include: (Unit is in no-load state or grid-connected state) & speed > 10% × rated speed & ((A set protection total trip signal is activated & A set protection trip signal is activated) or (B set protection total trip signal is activated & B set protection trip signal is activated)); The second category of mechanical accidents specifically include: 1) Major speed governor failure; 2) Speed ​​governor startup failure; 3) Unit overspeed; 4) Hydraulic system low pressure triggering; 5) Hydraulic system power failure; 6) Water generator backup protection triggering; 7) Emergency stop button triggering; 8) Spindle seal water source midsection; 9) Pure water system failure; 10) Protective device locked; 11) Low water flow; 12) Low cooling water flow of upper oil cooler; 13) Low cooling water flow of thrust / lower oil cooler; Any of the 13 mechanical accidents will trigger a Class II mechanical accident. The water turbine backup protection actions include thrust bearing temperature too high, lower guide bearing temperature too high, upper guide bearing temperature too high and water guide bearing temperature too high. If any one of the signals is triggered, it will be considered as the water turbine backup protection action.

5. According to the intelligent operation method for dismantling electrical equipment in a hydropower station according to claim 4, executing the switch-over maintenance of the generator-transformer group outlet in Step 2 includes: Push up the grounding switch on the transformer side and the grounding switch on the busbar side; The transformer neutral point grounding switch power-off operation includes: switching the neutral point grounding switch control mode of the transformer high-voltage side to "local ground" and disconnecting the operating power supply.

6. According to the intelligent operation method for disassembling electrical equipment in a hydropower station according to claim 1, the step 3 of performing the relevant preparation operations for measuring the insulation of the generator rotor specifically comprises: 1) Turn the AC power switch of the electric brake circuit to the "maintenance" position; 2) Disconnect the transformer group related failure protection link; 3) Disconnect the injection-type rotor single-point grounding protection link; 4) Disconnect the ping-pong type rotor single-point grounding protection link; 5) Disconnect the rotor grounding device power switch; 6) Disconnect the excitation system AC demagnetization switch; 7) Disconnect the excitation system DC demagnetization switch (19); 8) Disconnect the excitation system excitation power switch; 9) Disconnect the excitation system excitation power signal fuse; 10) Disconnect the rotor measurement fuse; 11) Disconnect the rotor single-point grounding) demagnetization circuit fuse; 12) Disconnect the ping-pong type rotor grounding protection fuse; 13) Check that no one is working in the rotor circuit and slip ring chamber. After all the above operations are completed in the order of 1-13, the generator rotor insulation measurement conditions can be met. Turning the AC power switch of the electric brake circuit to the "maintenance" position can prevent power from entering the rotor through the electric brake circuit; Exiting the relevant protection link during operations 2-4 of the generator rotor insulation measurement preparation process can prevent grounding protection from being activated during stator insulation measurement, and prevent failure protection from affecting other equipment.

7. According to the intelligent operation method for disassembling electrical equipment in a hydropower station according to claim 6, the generator rotor insulation measurement operation in Step 4 specifically includes: 1) Check that the rotor insulation meter and its wiring are intact and functioning properly; 2) Verify that there is no voltage in the unit rotor circuit; 3) Measure the generator rotor insulation; 4) Check that the generator rotor insulation is qualified; 5) Discharge the generator rotor circuit to ground. If all of the above are met, the generator rotor insulation measurement operation is considered complete; The rotor insulation measuring meter is connected to the rotor circuit through switch control and incoming main power supply control.

8. According to the intelligent operation method for disassembling electrical equipment of a hydropower station according to claim 7, the step 5 of performing the relevant preparation operations for measuring the insulation of the generator stator specifically comprises: 1) Check that the low-voltage side switch of the plant's high-voltage transformer is disconnected; 2) Check that the AC power switch of the electrical brake circuit is in the "maintenance" position; 3) Check that the relevant failure protection links of the generator-transformer group are disconnected; 4) Disconnect the generator stator grounding protection link; 5) Disconnect the generator electric brake open circuit function connector; 6) Disconnect the stator ground protection power switch; 7) Check that the AC de-excitation switch of the excitation system is disconnected; 8) Check that the DC de-excitation switch of the excitation system is disconnected; 9) Check that the excitation system starting power switch is disconnected; 10) Check that the excitation system starting power signal fuse is removed; 11) Check that the generator electrical brake short-circuit switch is disconnected; 12) Check that the generator electrical brake short-circuit grounding switch is open; 13) Push up the generator electrical brake short-circuit grounding switch and close the generator electrical brake short-circuit switch; 14) Disconnect the generator PT secondary switch; 15) Disconnect the neutral point grounding wire on the generator PT primary side; 16) Disconnect the generator electrical brake short-circuit switch and pull up the generator electrical brake short-circuit grounding switch; 17) Pull out the generator neutral point grounding switch; 18) Check that the generator pure water system is operating normally; 19) Disconnect the ground wire of the generator pure water cooling ring pipe; 20) Use a multimeter to measure the insulation resistance of the ring pipe to ground. The value should be greater than 10kΩ. After all the above operations are completed in the order of 1-20, the generator stator insulation measurement conditions are met.

9. According to the intelligent operation method for disassembling electrical equipment in a hydropower station according to claim 8, the generator stator insulation measurement operation in Step 6 specifically includes: 1) Check that the insulation resistance measuring meter and its wiring of the water-cooled generator are intact and functioning properly; 2) Switch the voltage switch of the insulation resistance measuring meter of the water-cooled generator to "2500V" and measure the stator insulation; 3) Record the stator insulation measurement meter's 、 、 value, and check whether the generator stator insulation is qualified; 4) Turn off the stator insulation measuring meter; 5) Discharge the stator wire rods and pure water ring pipe to the ground, and re-lead the ground wire of the generator pure water cooling ring pipe; If all the above operations are met, the generator stator insulation measurement operation is completed.

10. According to the intelligent operation method for disconnecting electrical equipment in a hydropower station according to claim 9, the disconnection operation of the generator auxiliary equipment and related electrical equipment in Step 7 specifically includes: 1) detecting that there is no voltage at the neutral point grounding switch of the generator, and short-circuiting the moving and static contacts to ground respectively; 2) engaging the mechanical brake damper, switching the control mode to "manual", and closing the mechanical brake exhaust valve; 3) stopping the pure water system and disconnecting the power supply; 4) detecting that there is no voltage on the high and low voltage sides of the excitation transformer, and grounding the high and low voltage three phases of the excitation transformer; 5) pushing up the generator electrical brake short-circuit grounding switch, closing the generator electrical brake short-circuit switch, switching the control mode to "manual", and disconnecting the power supply; 6) checking that the generator outlet switch is disconnected, pushing up the generator outlet isolation switch, and disconnecting the power supply; 7) detecting that there is no voltage on the high and low voltage sides of the plant high voltage transformer, and grounding the high and low voltage three phases of the plant high voltage transformer. The disconnection operation process is completed by following the above operations in the order of 1-7.

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