A large hydro-generator speed regulation system oil press device and oil press pump control method

Abstract

This invention provides a hydraulic pressure device for a large hydro-generator speed control system, comprising a governor main oil pipe, a pressure oil tank, a return oil tank, an oil cooler, and an electrostatic oil filter. The pressure oil tank is connected to the end of the governor main oil pipe and is connected to an air tank for pressurizing the pressure oil. Several sets of low-power and high-power hydraulic pressure systems are connected in parallel on the governor main oil pipe. The low-power hydraulic pressure system consists of a loading / unloading valve group, an oil filter, and a small pump connected in series. The high-power hydraulic pressure system consists of a loading / unloading valve group, an oil filter, and a large pump connected in series. The return oil tank is connected to each loading / unloading valve group. The oil cooler is located between the return oil tank and the loading / unloading valve groups. A control method for the hydraulic pressure pumps in a large hydro-generator speed control system is also provided. This method provides a stable pressure oil source for the speed control system through specific process control, while reducing energy consumption and costs. The hydraulic pressure pumps automatically rotate and are periodically dehumidified to ensure safe and stable operation of the equipment.

Description

Technical Field

[0001] This invention relates to the field of generator oil pump control technology, and in particular to an oil pump control method for a speed regulation system of a large hydro-generator. Background Technology

[0002] The governor is one of the most important control devices in a hydro-generator unit. The governor's hydraulic system is a crucial component, primarily consisting of a pressure oil tank and air tank, a return oil tank, an oil pump motor unit, hydraulic valve assemblies, and other accessories. The governor's hydraulic system provides the power source for operation and control of the governor through the control of the hydraulic system, ensuring the safe and stable operation of the turbine. The specific process is as follows: Atmospheric pressure turbine oil stored in the return oil tank is pressurized by a pressure pump and transported to the pressure oil tank. The high-pressure turbine oil in the pressure tank then circulates through the governor system's oil circuit to regulate the turbine and perform work. After performing work, the turbine oil changes from high pressure to atmospheric pressure and returns to the return oil tank. The returned turbine oil is then pressurized again by the pressure pump, preparing for the next work cycle, and this cycle repeats continuously.

[0003] Currently, the hydraulic pump motor unit of a speed governor typically consists of 3-4 hydraulic pumps and their motors. During the operation of the speed governor hydraulic system, one pump operates continuously as the main pump to maintain system pressure, while the others remain on standby. When the speed governor hydraulic system is started again, the main pump is rotated, and another pump is started as the main pump. If the speed governor system operates continuously for a long time, and the main pump continues to operate without rotation, the equipment will experience fatigue and a reduced service life; conversely, the standby pumps will be shut down for extended periods, making the motor susceptible to moisture damage and reduced insulation, leading to equipment damage. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a hydraulic oil pressurization device and hydraulic oil pump control method for a large-scale hydro-generator speed regulation system. To achieve the above objectives, this invention adopts the following technical solution:

[0005] This invention provides a pressure oil device for a speed regulating system of a large hydro-generator, including a governor main oil pipe, a pressure oil tank, a return oil tank, an oil cooler, and an electrostatic oil filter. The pressure oil tank is connected to the end of the governor main oil pipe and is connected to an air tank for pressurizing the pressure oil tank. Several sets of small-power and high-power pressure oil systems are connected in parallel on the governor main oil pipe. The small-power pressure oil system consists of a loading / unloading valve group, an oil filter, and a small pump connected in series. The high-power pressure oil system consists of a loading / unloading valve group, an oil filter, and a large pump connected in series. Both the small pump and the large pump are connected to the return oil tank, which is connected to each loading / unloading valve group. The oil cooler is located between the return oil tank and the loading / unloading valve group, and the electrostatic oil filter is installed on the return oil tank.

[0006] Furthermore, the power range of the small pump is 10~60kw, and the power range of the large pump is 120~200kw.

[0007] Furthermore, there are two small pumps, P1 and P2, and two large pumps, P3 and P4.

[0008] This invention also provides a method for controlling the hydraulic pump of a large hydro-generator speed regulation system, utilizing the hydraulic pump device described above, and including the following steps: If the hydraulic system is in a shutdown state, and the remote start conditions are met, upon receiving a start command from the monitoring hydraulic system, a large pump is started to load and run. After the system pressure rises to the rated working pressure, the pump unloads, and a small pump starts to run. The large pump is then stopped. The hydraulic system pressure is maintained at the rated working pressure through the loading and unloading control of the small pump to ensure the normal operation of the speed governor. If both large pumps are unavailable, the monitoring system issues a command to stop the hydraulic system and reports a major hydraulic system fault. If both small pumps are unavailable, the status of the large pump is assessed. If both large pumps are available, a hydraulic system fault is reported, and the current large pump is kept running. The speed governor hydraulic system is maintained to operate normally through the loading and unloading control of the large pump. Otherwise, the monitoring system issues a command to stop the hydraulic system and reports a major hydraulic system fault. The main operating pump is rotated and controlled. When the main operating pump runs continuously for 72 hours or fails, the main operating pump is switched over and another small pump is started. If the start is successful, the original operating pump is stopped and the process ends. If the start fails, a pump failure is reported. If the main pump switch fails, the original main pump is maintained. If both small pumps fail, either large pump is started. When the hydraulic system is running, the hydraulic system pressure and oil level in the pressure tank are maintained within the normal operating range by controlling the loading and unloading of the currently running pump. When the system pressure is less than the rated working pressure or the oil level in the pressure tank is less than 2000 mm, the pressure pump is loaded and running. When the system pressure is greater than the rated working pressure or the oil level in the pressure tank is greater than 2700 mm, the pressure pump is unloaded and running. If the loading and unloading of the pressure pump fails, a pressure pump fault is reported and the main pump is replaced. When the hydraulic system is running normally, the system pressure is maintained by loading and unloading control of a small pump. If the system pressure is too low, a large pump is needed to assist in loading and running, so as to quickly pressurize the hydraulic system to the rated working pressure. When the speed governor hydraulic system is running normally, the system pressure is maintained by loading and unloading the small pump. The large pump is in a state of long-term shutdown. When the hydraulic system is shut down for a long time, all oil pumps are in a state of long-term shutdown. The oil pump motor is dehumidified periodically by process control. The pressure oil pump is in automatic mode with no fault alarm. When the continuous shutdown time of the large pump reaches 168 hours, the large pump is started. If the large pump starts successfully, the continuous shutdown time of the large pump is reset to zero. After the large pump runs for 1 hour, it is stopped, and the continuous shutdown time of the large pump is restarted. If the large pump fails to start, a pump fault is reported, and the dehumidification of the pressure oil pump fails.

[0009] Furthermore, the conditions for remote starting of the hydraulic system include the local control mode of the hydraulic system, major faults in the hydraulic system, low pressure in the pressure tank, low liquid level in the pressure tank, and low liquid level in the return tank. If any of these conditions are met, the hydraulic system cannot be started remotely.

[0010] Furthermore, the control methods for switching to the small pump after starting the large pump and loading it include: Step 1: The speed controller hydraulic system receives the start command of the monitoring hydraulic system and determines whether the start conditions of the hydraulic system are met. If the conditions are met, proceed to the next step; if the start conditions are not met, jump to step 11. Step 2: Compare the cumulative running time of the two pumps P3 and P4, and take the shorter time. Start pump P3 or P4 and proceed to the next step. Step 3: Determine whether pump P3 or P4 has started successfully. If pump P3 or P4 has started successfully, proceed to the next step. If pump P3 or P4 has failed to start, proceed to step 5. Step 4: Loading command for P3 or P4 pump. Determine whether P3 or P4 pump is successfully loaded. If P3 or P4 pump is successfully loaded, compare the system pressure Y1 with the set value in real time. If Y1 is less than the rated working pressure, P3 or P4 pump continues to run under load. If Y1 is greater than the rated working pressure, proceed to step 7. If P3 or P4 pump fails to load, stop pump P3 or P4 and proceed to the next step. Step 5: Alarm "P3 or P4 pump is faulty and unavailable". Start another large pump P4 or P3 and determine whether P4 or P3 pump starts successfully. If P4 or P3 pump starts successfully, proceed to the next step. If P4 or P3 pump fails to start, alarm "Both large pumps P3 and P4 are faulty and unavailable" will be triggered, and the process will jump to step 11. Step 6: Loading command for P4 or P3 pump. Determine whether P4 or P3 pump is successfully loaded. If P4 or P3 pump is successfully loaded, compare the system pressure Y1 with the set value in real time. If Y1 is less than the rated working pressure, P4 or P3 pump continues to run under load. If Y1 is greater than the rated working pressure, proceed to the next step. Step 7: Unload the currently running pump P3 or P4, compare the cumulative running time of the two smaller pumps P1 and P2, select the one with the shorter time, start the pump P1 or P2, and proceed to the next step. Step 8: Determine if pump P1 or P2 has started successfully. If pump P1 or P2 has started successfully, proceed to the next step. If pump P1 or P2 fails to start, an alarm will sound "P1 or P2 pump is faulty and unavailable". Start another small pump P2 or P1 and determine if pump P2 or P1 has started successfully. If pump P2 or P1 starts successfully, proceed to step 9. If pump P2 or P1 fails to start, an alarm will sound "Both small pumps P1 and P2 are faulty and unavailable", and the process will jump to step 10. Step 9: Stop the currently running main pump P3 or P4. The hydraulic system startup is complete, and the process ends. Step 10: Determine the status of the two large pumps P3 and P4. If both large pumps P3 and P4 are functioning properly, keep the currently operating large pump P3 or P4 running. The hydraulic system startup is complete, and the process ends. If either P3 or P4 is faulty and unavailable, proceed to the next step. Step 11: An alarm "Major hydraulic system malfunction" is triggered. The hydraulic system is then stopped, and the process ends.

[0011] Furthermore, the main pump switching control method includes: Step 12: Hydraulic system in operation, P1 or P2 pump is running. If P1 or P2 pump fails, an alarm "P1 or P2 pump is faulty and unavailable" will be triggered, and the next step will be executed. If P1 or P2 pump is running normally, the continuous running time of P1 or P2 pump is compared with the set value in real time. If the continuous running time is <72h, keep P1 or P2 pump running. If the continuous running time is ≥72h, the next step will be executed. Step 13: Issue a main pump switching command to start pump P2 or P1. Determine whether pump P2 or P1 has started successfully. If pump P2 or P1 starts successfully, proceed to the next step. If pump P2 or P1 fails to start, an alarm "P2 or P1 pump is faulty and unavailable" will be triggered, and the process will jump to step 15. Step 14: Stop pump P1 or P2. The main pump switchover is complete, and the process ends. Step 15: Determine whether both small pumps P1 and P2 are faulty and unusable. If so, proceed to the next step; otherwise, skip to step 17. Step 16: Start one of the main pumps, P3 or P4, and the alarm "Main pump switching failed" will be triggered, at which point the process ends. Step 17: Keep the original main pump P1 or P2 running, and the alarm "Main pump switchover failed" will be triggered, and the process will end.

[0012] Furthermore, the hydraulic pump loading and unloading control methods include: Step 18: Hydraulic system in operation, P1 or P2 pump running, real-time comparison of hydraulic system pressure and pressure tank oil level sampling value with set value. If the system pressure is less than the rated working pressure or the pressure tank oil level is <2000mm, proceed to the next step. If the system pressure is greater than the rated working pressure or the pressure tank oil level is >2700mm, jump to step 20. Step 19: Loading command for P1 or P2 pump. Determine whether P1 or P2 pump is successfully loaded. If P1 or P2 pump is successfully loaded, proceed to step 1. If P1 or P2 pump fails to load, proceed to step 21. Step 20: Unload P1 or P2 pump. Determine whether P1 or P2 pump has been successfully unloaded. If P1 or P2 pump has been successfully unloaded, proceed to step 1. If P1 or P2 pump has failed to unload, proceed to the next step. Step 21: Alarm "P1 or P2 pump is faulty and unavailable", start the main pump switchover control process.

[0013] Furthermore, hydraulic system-assisted loading control methods include: Step 22: Hydraulic system in operation. Compare the hydraulic system pressure with the set value in real time. If the system pressure is greater than the rated working pressure, proceed to the next step. If the system pressure is less than the rated working pressure, jump to step 24. If the hydraulic system pressure is less than the rated working pressure, jump to step 25. Step 23: If the number of operating oil pumps is greater than 1, unload and stop one large pump, and proceed to step 22. Step 24: If the number of operating oil pumps is less than 2, start one large pump and run it under load, then proceed to step 22. Step 25: If the number of operating oil pumps is less than 3, start one large pump to load and run it, then proceed to step 22.

[0014] Furthermore, the dehumidification control method for the oil pump motor includes: Step 26: If there is no fault alarm for oil pressure pumps P1, P2, P3 or P4 and the mode is "automatic", compare the continuous shutdown time of oil pressure pumps P1, P2, P3 or P4 with the set value in real time. If the continuous shutdown time is >168h, proceed to the next step. Step 27: Start oil pump P1, P2, P3 or P4, and determine whether oil pump P1, P2, P3 or P4 has started successfully. If oil pump P1, P2, P3 or P4 starts successfully, proceed to the next step. If oil pump P1, P2, P3 or P4 fails to start, jump to step 30. Step 28: Reset the continuous running time of oil pumps P1, P2, P3 or P4 to zero, delay for 1 hour, and then proceed to the next step; Step 29: Stop oil pumps P1, P2, P3 or P4, start timing for continuous pump downtime, and jump to step 26; Step 30: Alarm "Oil pump P1, P2, P3 or P4 is faulty and unavailable" "Oil pump P1, P2, P3 or P4 dehumidification failed", process ends. Attached Figure Description

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments: Figure 1 This is a schematic diagram of the hydraulic device according to an embodiment of the present invention; Figure 2 This is a flowchart illustrating the control process of switching to the small pump after the large pump is started and running, according to an embodiment of the present invention. Figure 3 This is a flowchart of the main pump switching control according to an embodiment of the present invention; Figure 4This is a flowchart illustrating the loading and unloading control of the hydraulic oil pump according to an embodiment of the present invention. Figure 5 This is a flowchart of the auxiliary loading control process of the hydraulic system according to an embodiment of the present invention; Figure 6 This is a flowchart of the dehumidification control process for the oil pump motor in an embodiment of the present invention.

[0016] In the above attached diagram: pressure oil tank 1, air tank 2, return oil tank 3, small pump 4, small pump 5, large pump 6, large pump 7, governor main oil pipe 8, governor system pressure Y1, oil tank pressure Y2, loading and unloading valve group 11, oil filter 12, oil cooler 13, electrostatic oil filter 14. Detailed Implementation

[0017] The technical solutions of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0018] like Figure 1 As shown, the present invention provides a pressure oil device for a speed regulating system of a large hydro-generator, including a governor main oil pipe 8, a pressure oil tank 1, a return oil tank 3, an oil cooler 13, and an electrostatic oil filter 14. The pressure oil tank 1 is connected to the end of the governor main oil pipe 8, and the pressure oil tank 1 is connected to an air tank 2 for pressurizing the pressure oil tank 1. Several sets of small-power and high-power pressure oil systems are connected in parallel on the governor main oil pipe 8. The small-power pressure oil system is composed of a loading and unloading valve group 11, an oil filter 12, and small pumps 4 and 5 connected in series. The high-power pressure oil system is composed of a loading and unloading valve group 11, an oil filter 12, and large pumps 6 and 7 connected in series. The small pumps 4 and 5 and the large pumps 6 and 7 are all connected to the return oil tank 3. The return oil tank 3 is connected to each loading and unloading valve group 11. The oil cooler 13 is located between the return oil tank 3 and the loading and unloading valve group 11. The electrostatic oil filter 14 is installed on the return oil tank 3.

[0019] Furthermore, the power range of the small pump is 10~60kw, including 10KW, 20KW, 30KW, 40KW, 50KW, and 60KW, and the power range of the large pump is 120~200kw, including 120KW, 150KW, 160KW, 180KW, and 200KW.

[0020] Furthermore, two small pumps are provided, namely P1 and P2, and two large pumps are provided, namely P3 and P4. This design selects an oil pump motor unit consisting of two large pumps (160kW motor power) and two small pumps (30kW motor power), reducing equipment costs. The small pumps, acting as the main pumps, operate continuously, making them more energy-efficient and environmentally friendly compared to the large pumps.

[0021] When the speed governor hydraulic system is running normally, the two small pumps take turns running. When the continuous running time of the small pump reaches 72 hours, the main pump is switched over to the other small pump.

[0022] When the speed governor hydraulic system is running normally, only one small pump needs to operate. The system pressure is maintained by loading and unloading the main pump. When the system pressure is too low, the large pump is started to assist in loading and unloading, so that the system pressure can quickly reach the normal working pressure.

[0023] If the oil pump is continuously shut down for 168 hours, start the pump and run it for one hour to prevent the pump motor from getting damp, reducing insulation, and causing motor damage.

[0024] This invention also provides a method for controlling the hydraulic pump of a large hydro-generator speed regulation system, utilizing the hydraulic pump device described above, and including the following steps: If the hydraulic system is in a shutdown state, and the remote start conditions are met, upon receiving a start command from the monitoring hydraulic system, a large pump is started to load and run. After the system pressure rises to the rated working pressure, the pump unloads, and a small pump starts to run. The large pump is then stopped. The hydraulic system pressure is maintained at the rated working pressure through the loading and unloading control of the small pump to ensure the normal operation of the speed governor. If both large pumps are unavailable, the monitoring system issues a command to stop the hydraulic system and reports a major hydraulic system fault. If both small pumps are unavailable, the status of the large pump is assessed. If both large pumps are available, a hydraulic system fault is reported, and the current large pump is kept running. The speed governor hydraulic system is maintained to operate normally through the loading and unloading control of the large pump. Otherwise, the monitoring system issues a command to stop the hydraulic system and reports a major hydraulic system fault. The main operating pump is rotated and controlled. When the main operating pump runs continuously for 72 hours or fails, the main operating pump is switched over and another small pump is started. If the start is successful, the original operating pump is stopped and the process ends. If the start fails, a pump failure is reported. If the main pump switch fails, the original main pump is maintained. If both small pumps fail, either large pump is started. When the hydraulic system is running, the hydraulic system pressure and oil level in the pressure tank are maintained within the normal operating range by controlling the loading and unloading of the currently running pump. When the system pressure is less than the rated working pressure or the oil level in the pressure tank is less than 2000 mm, the pressure pump is loaded and running. When the system pressure is greater than the rated working pressure or the oil level in the pressure tank is greater than 2700 mm, the pressure pump is unloaded and running. If the loading and unloading of the pressure pump fails, a pressure pump fault is reported and the main pump is replaced. When the hydraulic system is running normally, the system pressure is maintained by loading and unloading control of a small pump. If the system pressure is too low, a large pump is needed to assist in loading and running, so as to quickly pressurize the hydraulic system to the rated working pressure. When the speed governor hydraulic system is running normally, the system pressure is maintained by loading and unloading the small pump. The large pump is in a state of long-term shutdown. When the hydraulic system is shut down for a long time, all oil pumps are in a state of long-term shutdown. The oil pump motor is dehumidified periodically by process control. The pressure oil pump is in automatic mode with no fault alarm. When the continuous shutdown time of the large pump reaches 168 hours, the large pump is started. If the large pump starts successfully, the continuous shutdown time of the large pump is reset to zero. After the large pump runs for 1 hour, it is stopped, and the continuous shutdown time of the large pump is restarted. If the large pump fails to start, a pump fault is reported, and the dehumidification of the pressure oil pump fails.

[0025] The control process for starting the speed governor hydraulic system by the monitoring system is as follows: When starting the governor's hydraulic system, its pressure needs to be adjusted to the working pressure of 6.1-6.3 MPa as soon as possible. First, start the large pump to load and increase the hydraulic system pressure to 6.3 MPa, then start the small pump to maintain the system pressure. The control process is as follows: When the hydraulic system is shut down, if the remote start conditions are met, a large pump will be started upon receiving the start order from the monitored hydraulic system (prioritizing the pump with the shortest cumulative running time). Once the system pressure rises to 6.3 MPa, the pump will unload, and a small pump will be started (prioritizing the pump with the shortest cumulative running time). The large pump will then be stopped. The hydraulic system pressure will be maintained between 6.1 and 6.3 MPa by controlling the loading and unloading of the small pump, ensuring the normal operation of the speed governor.

[0026] If both large pumps are unavailable, the monitoring system will issue a command to stop the hydraulic system and report a major hydraulic system malfunction.

[0027] If both small pumps are unavailable, the status of the large pump is checked. If both large pumps are available, a hydraulic system fault is reported, and the current operation of the large pump is maintained. The speed governor hydraulic system is kept running normally through the loading and unloading control of the large pump. Otherwise, the monitoring system issues a command to stop the hydraulic system and reports a major hydraulic system fault.

[0028] like Figure 2 As shown, the specific steps are as follows: Step 1: The speed controller hydraulic system receives the start command from the monitoring hydraulic system and determines whether the start conditions of the hydraulic system are met. If the conditions are met, proceed to the next step; if the start conditions are not met, jump to step 11.

[0029] Step 2: Compare the cumulative running time of the two pumps P3 and P4, and take the shorter time. Start the pump P3 (P4) and proceed to the next step.

[0030] Step 3: Determine whether pump P3 (P4) has started successfully. If pump P3 (P4) has started successfully, proceed to the next step; if pump P3 (P4) has failed to start, proceed to step 5.

[0031] Step 4: Loading command for pump P3 (P4): Determine if pump P3 (P4) is successfully loaded. If pump P3 (P4) is successfully loaded, compare the system pressure Y1 with the set value in real time. If Y1 < 6.3 MPa, pump P3 (P4) continues to run under load; if Y1 ≥ 6.3 MPa, proceed to step 7. If pump P3 (P4) fails to load, stop pump P3 (P4) and proceed to the next step.

[0032] Step 5: Alarm "P3 (P4) pump is faulty and unavailable", start another large pump P4 (P3) and determine whether P4 (P3) pump starts successfully. If P4 (P3) pump starts successfully, proceed to the next step. If P4 (P3) pump fails to start, alarm "Both large pumps P3 and P4 are faulty and unavailable", jump to step 11.

[0033] Step 6: Loading command for P4 (P3) pump. Determine if P4 (P3) pump is successfully loaded. If P4 (P3) pump is successfully loaded, compare the system pressure Y1 with the set value in real time. If Y1 < 6.3 MPa, P4 (P3) pump continues to run under load; if Y1 ≥ 6.3 MPa, proceed to the next step.

[0034] Step 7: Unload the currently running pump P3 or P4, compare the cumulative running times of the two smaller pumps P1 and P2, and start the pump with the shorter time to proceed to the next step. Step 8: Determine if pump P1 (P2) has started successfully. If pump P1 (P2) has started successfully, proceed to the next step. If pump P1 (P2) fails to start, an alarm will sound "P1 (P2) pump is faulty and unavailable". Start another small pump P2 (P1) and determine if pump P2 (P1) has started successfully. If pump P2 (P1) has started successfully, proceed to step 9. If pump P2 (P1) fails to start, an alarm will sound "Both small pumps P1 and P2 are faulty and unavailable", and proceed to step 10.

[0035] Step 9: Stop the currently running main pump P3 or P4. The hydraulic system startup is complete, and the process ends.

[0036] Step 10: Determine the status of the two main pumps, P3 and P4. If both pumps P3 and P4 are functioning correctly, maintain the operation of either pump P3 or P4. The hydraulic system startup is complete, and the process ends. If either P3 or P4 fails and becomes unavailable, proceed to the next step.

[0037] Step 11: Alarm "Major hydraulic system malfunction", shut down the hydraulic system, and the process ends.

[0038] The main pump switching control process is as follows: During normal operation of the hydraulic system, the pressure is maintained by controlling the loading and unloading of small pumps. Prolonged continuous operation of the hydraulic pump can cause metal fatigue in the pump and motor, reducing equipment lifespan and affecting the safe and stable operation of the hydraulic system. Therefore, the main operating pump is rotated. When the main operating pump has been running continuously for 72 hours or fails, the main pump is switched over, and another small pump is started. If the start is successful, the original main pump is stopped, and the process ends. If the start fails, a pump failure is reported, the main pump switchover fails, and the original main pump continues to operate. If both small pumps fail, either large pump is started.

[0039] like Figure 3 As shown, the specific steps are as follows: Step 12: Hydraulic system in operation, P1 (P2) pump is running. If P1 (P2) pump fails, an alarm "P1 (P2) pump failure, unavailable" will be triggered, and the next step will be executed. If P1 (P2) pump is running normally, the continuous running time of P1 (P2) pump is compared with the set value in real time. If the continuous running time is <72h, keep P1 (P2) pump running. If the continuous running time is ≥72h, the next step will be executed.

[0040] Step 13: Issue a main pump switching command to start pump P2 (P1). Determine if pump P2 (P1) has started successfully. If pump P2 (P1) has started successfully, proceed to the next step. If pump P2 (P1) fails to start, issue an alarm "P2 (P1) pump is faulty and unavailable" and proceed to step 15.

[0041] Step 14: Stop pump P1 (P2), the main pump switchover is complete, and the process ends.

[0042] Step 15: Determine if both small pumps P1 and P2 are faulty and unusable. If yes, proceed to the next step; otherwise, skip to step 17.

[0043] Step 16: Start one of the main pumps, P3 or P4, and the alarm "Main pump switching failed" will be triggered, ending the process.

[0044] Step 17: Keep the original main pump P1 (P2) running, alarm "Main pump switchover failed", process ends.

[0045] The oil pump loading and unloading control process is as follows: During hydraulic system operation, the hydraulic system pressure and pressure tank oil level are maintained within the normal operating range by controlling the loading and unloading of the currently operating pump. When the system pressure is <6.1MPa or the pressure tank oil level is <2000mm, the pressure pump operates under load; when the system pressure is >6.3MPa or the pressure tank oil level is >2700mm, the pressure pump operates under unload. If the pressure pump loading / unloading fails, a pressure pump fault is reported, and the main pump is replaced.

[0046] like Figure 4 As shown, the specific steps are as follows: Step 18: Hydraulic system in operation, P1 (P2) pump running. Real-time comparison of hydraulic system pressure and pressure tank oil level sampling values ​​with set values. If system pressure < 6.1 MPa or pressure tank oil level < 2000 mm, proceed to the next step; if system pressure > 6.3 MPa or pressure tank oil level > 2700 mm, jump to step 20.

[0047] Step 19: Loading command for pumps P1 (P2), determine whether pumps P1 (P2) are loaded successfully. If pumps P1 (P2) are loaded successfully, proceed to step 1; if pumps P1 (P2) fail to load, proceed to step 21.

[0048] Step 20: Unload P1 (P2) pump. Determine if pump P1 (P2) was successfully unloaded. If pump P1 (P2) was successfully unloaded, proceed to step 1; if pump P1 (P2) failed to unload, proceed to the next step.

[0049] Step 21: Alarm "P1 (P2) pump is faulty and unavailable", start the main pump switchover control process.

[0050] The hydraulic system auxiliary loading control process is as follows: During normal operation, the hydraulic system maintains its pressure by using a small pump for loading and unloading. If the system pressure is too low, a large pump is needed to assist in loading and quickly pressurize the hydraulic system to its rated working pressure.

[0051] like Figure 5 As shown, the specific steps are as follows: Step 22: Hydraulic system operation status. Compare the hydraulic system pressure with the set value in real time. If the system pressure > 6.1 MPa, proceed to the next step; if the system pressure < 5.8 MPa, skip to step 3; if the hydraulic system pressure < 5.5 MPa, skip to step 25.

[0052] Step 23: If the number of operating oil pumps is greater than 1, then unload and stop one large pump, and proceed to step 22.

[0053] Step 24: If the number of operating oil pumps is less than 2, start one large pump and proceed to step 22.

[0054] Step 25: If the number of operating oil pumps is less than 3, start one large pump to load and run it, then proceed to step 22.

[0055] The dehumidification control process for the oil pump motor is as follows: During normal operation, the speed governor hydraulic system maintains system pressure through the loading and unloading control of a small pump, while the large pump remains in a state of long-term inactivity. When the hydraulic system is shut down for extended periods, all oil pumps remain in a state of inactivity. If the oil pump motors are not operated for a long time, they will become damp, leading to decreased motor insulation and equipment damage. Therefore, process control is used to periodically dehumidify the oil pump motors to prevent moisture damage to the equipment. The control process is as follows: In automatic mode, with no fault alarms, if the pump has been continuously shut down for 168 hours, start the pump. If the pump starts successfully, the continuous shutdown time is reset to zero. The pump will run for 1 hour before stopping, and the continuous shutdown time will restart. If the pump fails to start, a pump fault will be reported, indicating that the oil pressure pump dehumidification has failed.

[0056] like Figure 6 As shown, the specific steps are as follows: Step 26: If there is no fault alarm for oil pressure pump P1 (P2P3P4) and the mode is "automatic", compare the continuous shutdown time of oil pressure pump P1 (P2P3P4) with the set value in real time. If the continuous shutdown time is >168h, proceed to the next step.

[0057] Step 27: Start hydraulic pump P1 (P2P3P4) and determine whether hydraulic pump P1 (P2P3P4) has started successfully. If hydraulic pump P1 (P2P3P4) starts successfully, proceed to the next step; if hydraulic pump P1 (P2P3P4) fails to start, skip to step 30.

[0058] Step 28: Reset the continuous running time of oil pump P1 (P2P3P4) to zero, delay for 1 hour, and then proceed to the next step.

[0059] Step 29: Stop the oil pump P1 (P2P3P4), start the timer for the continuous pump stop time, and jump to step 26.

[0060] Step 30: Alarms "Oil pump P1 (P2P3P4) is faulty and unavailable" and "Oil pump P1 (P2P3P4) dehumidification failed", process ends.

[0061] This invention designs an oil pump motor unit consisting of two large pumps and two small pumps. Through specific process control, it provides a stable pressure oil source for the speed regulation system, while reducing energy consumption and lowering costs. The pressure oil pumps automatically rotate and are dehumidified periodically to ensure the safe and stable operation of the equipment.

Claims

1. A method for controlling the hydraulic oil pump in a large hydro-generator speed regulation system, characterized in that, The hydraulic pressurization device includes a governor main oil pipe, a pressure oil tank, a return oil tank, an oil cooler, and an electrostatic oil filter. The pressure oil tank is connected to the end of the governor main oil pipe and is connected to an air tank for pressurizing the oil. Several sets of small-power and large-power hydraulic pressurization systems are connected in parallel on the governor main oil pipe. The small-power hydraulic pressurization system consists of a loading / unloading valve group, an oil filter, and a small pump connected in series. The large-power hydraulic pressurization system consists of a loading / unloading valve group, an oil filter, and a large pump connected in series. Both the small and large pumps are connected to the return oil tank, which is connected to each loading / unloading valve group. The oil cooler is located between the return oil tank and the loading / unloading valve group. The electrostatic oil filter is installed on the return oil tank. The control method of the hydraulic pressurization device includes the following steps: If the hydraulic system is in a shutdown state, and the remote start conditions are met, upon receiving a start command from the monitoring hydraulic system, a large pump is started to load and run. After the system pressure rises to the rated working pressure, the pump unloads, and a small pump starts to run. The large pump is then stopped. The hydraulic system pressure is maintained at the rated working pressure through the loading and unloading control of the small pump to ensure the normal operation of the speed governor. If both large pumps are unavailable, the monitoring system issues a command to stop the hydraulic system and reports a major hydraulic system fault. If both small pumps are unavailable, the status of the large pump is assessed. If both large pumps are available, a hydraulic system fault is reported, and the current large pump is kept running. The speed governor hydraulic system is maintained to operate normally through the loading and unloading control of the large pump. Otherwise, the monitoring system issues a command to stop the hydraulic system and reports a major hydraulic system fault. The main operating pump is rotated and controlled. When the main operating pump runs continuously for 72 hours or fails, the main operating pump is switched over and another small pump is started. If the start is successful, the original operating pump is stopped and the process ends. If the start fails, a pump failure is reported. If the main pump switch fails, the original main pump is maintained. If both small pumps fail, either large pump is started. When the hydraulic system is running, the hydraulic system pressure and oil level in the pressure tank are maintained within the normal working range by controlling the loading and unloading of the currently running pump. When the system pressure is less than the rated working pressure, the pressure pump is loaded and running. When the system pressure is greater than the rated working pressure, the pressure pump is unloaded and running. If the loading and unloading of the pressure pump fails, a pressure pump fault is reported and the main pump is replaced. When the hydraulic system is running normally, the system pressure is maintained by loading and unloading control of a small pump. If the system pressure is too low, a large pump is needed to assist in loading and running, so as to quickly pressurize the hydraulic system to the rated working pressure. When the speed governor hydraulic system is running normally, the system pressure is maintained by loading and unloading the small pump. The large pump is in a state of long-term shutdown. When the hydraulic system is shut down for a long time, all oil pumps are in a state of long-term shutdown. The oil pump motor is dehumidified periodically by process control. The pressure oil pump is in automatic mode with no fault alarm. When the continuous shutdown time of the large pump reaches 168 hours, the large pump is started. If the large pump starts successfully, the continuous shutdown time of the large pump is reset to zero. After the large pump runs for 1 hour, it is stopped, and the continuous shutdown time of the large pump is restarted. If the large pump fails to start, a pump fault is reported, and the dehumidification of the pressure oil pump fails.

2. The method for controlling the hydraulic oil pump in a large hydro-generator speed regulation system as described in claim 1, characterized in that, The conditions for remote starting of a hydraulic system include the local control mode of the hydraulic system, major faults in the hydraulic system, low pressure in the pressure tank, low liquid level in the pressure tank, and low liquid level in the return tank. If any of these conditions are met, the hydraulic system cannot be started remotely.

3. The method for controlling the hydraulic oil pump in a large hydro-generator speed regulation system as described in claim 1, characterized in that, The control methods for switching to the small pump after the large pump has started and is running include: Step 1: The speed controller hydraulic system receives the start command of the monitoring hydraulic system and determines whether the start conditions of the hydraulic system are met. If the conditions are met, proceed to the next step; if the start conditions are not met, jump to step 11. Step 2: Compare the cumulative running time of the two pumps P3 and P4, and take the shorter time. Start pump P3 or P4 and proceed to the next step. Step 3: Determine whether pump P3 or P4 has started successfully. If pump P3 or P4 has started successfully, proceed to the next step. If pump P3 or P4 has failed to start, proceed to step 5. Step 4: Loading command for P3 or P4 pump. Determine whether P3 or P4 pump is successfully loaded. If P3 or P4 pump is successfully loaded, compare the system pressure Y1 with the set value in real time. If Y1 is less than the rated working pressure, P3 or P4 pump continues to run under load. If Y1 is greater than the rated working pressure, proceed to step 7. If P3 or P4 pump fails to load, stop pump P3 or P4 and proceed to the next step. Step 5: Alarm "P3 or P4 pump is faulty and unavailable". Start another large pump P4 or P3 and determine whether P4 or P3 pump starts successfully. If P4 or P3 pump starts successfully, proceed to the next step. If P4 or P3 pump fails to start, alarm "Both large pumps P3 and P4 are faulty and unavailable" will be triggered, and the process will jump to step 11. Step 6: Loading command for P4 or P3 pump. Determine whether P4 or P3 pump is successfully loaded. If P4 or P3 pump is successfully loaded, compare the system pressure Y1 with the set value in real time. If Y1 is less than the rated working pressure, P4 or P3 pump continues to run under load. If Y1 is greater than the rated working pressure, proceed to the next step. Step 7: Unload the currently running pump P3 or P4, compare the cumulative running time of the two smaller pumps P1 and P2, select the one with the shorter time, start the pump P1 or P2, and proceed to the next step. Step 8: Determine if pump P1 or P2 has started successfully. If pump P1 or P2 has started successfully, proceed to the next step. If pump P1 or P2 fails to start, an alarm will sound "P1 or P2 pump is faulty and unavailable". Start another small pump P2 or P1 and determine if pump P2 or P1 has started successfully. If pump P2 or P1 starts successfully, proceed to step 9. If pump P2 or P1 fails to start, an alarm will sound "Both small pumps P1 and P2 are faulty and unavailable", and the process will jump to step 10. Step 9: Stop the currently running main pump P3 or P4. The hydraulic system startup is complete, and the process ends. Step 10: Determine the status of the two large pumps P3 and P4. If both large pumps P3 and P4 are functioning properly, keep the currently operating large pump P3 or P4 running. The hydraulic system startup is complete, and the process ends. If either P3 or P4 is faulty and unavailable, proceed to the next step. Step 11: Alarm "Major hydraulic system malfunction" is triggered. The hydraulic system is stopped, and the process ends.

4. The method for controlling the hydraulic oil pump in a large hydro-generator speed regulation system as described in claim 3, characterized in that, The main pump switching control methods include: Step 12: Hydraulic system in operation, P1 or P2 pump is running. If P1 or P2 pump fails, an alarm "P1 or P2 pump is unavailable" will be triggered, and the next step will be executed. If P1 or P2 pump is running normally, the continuous running time of P1 or P2 pump is compared with the set value in real time. If the continuous running time is <72h, keep P1 or P2 pump running. If the continuous running time is ≥72h, the next step will be executed. Step 13: Issue a main pump switching command to start pump P2 or P1. Determine whether pump P2 or P1 has started successfully. If pump P2 or P1 starts successfully, proceed to the next step. If pump P2 or P1 fails to start, an alarm "P2 or P1 pump is faulty and unavailable" will be triggered, and the process will jump to step 15. Step 14: Stop pump P1 or P2. The main pump switchover is complete, and the process ends. Step 15: Determine whether both small pumps P1 and P2 are faulty and unusable. If so, proceed to the next step; otherwise, skip to step 17. Step 16: Start one of the main pumps, P3 or P4, and the alarm "Main pump switching failed" will be triggered, at which point the process ends. Step 17: Keep the original main pump P1 or P2 running, and the alarm "Main pump switchover failed" will be triggered, and the process will end.

5. The method for controlling the hydraulic oil pump in a large hydro-generator speed regulation system as described in claim 1, characterized in that, The power range of the small pump is 10~60kw, and the power range of the large pump is 120~200kw.

6. The method for controlling the hydraulic oil pump in a large hydro-generator speed regulation system as described in claim 1, characterized in that, There are two small pumps, P1 and P2, and two large pumps, P3 and P4.

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