阅读说明：本技术 用于混流式水轮发电机组监控系统的一键开导叶排水流程 (One-key opening guide vane drainage process for mixed-flow type hydroelectric generating set monitoring system ) 是由 熊腾清 陈哲之 李文锋 李初辉 杨赛 于 2021-09-14 设计创作，主要内容包括：本发明公开了用于混流式水轮发电机组监控系统的一键开导叶排水流程,步骤1,一键开导叶排水流程启动条件设计：监控发出“一键开导叶排水流程启动”令后,流程启动前需要判断的条件,条件满足方可启动流程；步骤2,分析机组运行工况,确定设备操作的顺序和转换条件,绘制一键开导叶排水流程图；步骤3,一键开导叶排水流程启动优先级设置；步骤4,机组事故停机流程启动条件优化；步骤5,调速器控制模型设计。通过在水电站计算机监控系统程序上设计一套专门的顺控流程,通过监控一键启动开导叶排水流程,实现流程自动、快速、安全排出引水隧洞内积水的目的。(The invention discloses a one-key opening guide vane drainage process for a mixed-flow type hydroelectric generating set monitoring system, which comprises the following steps of 1, designing starting conditions of the one-key opening guide vane drainage process: after a 'one-key opening guide vane drainage process starting' order is sent out by monitoring, the conditions needing to be judged before the process is started are met, and the process can be started; step 2, analyzing the operation condition of the unit, determining the sequence and conversion conditions of equipment operation, and drawing a one-key opening guide vane drainage flow chart; step 3, starting priority setting of a one-key opening guide vane drainage process; step 4, optimizing the starting conditions of the unit accident shutdown process; and 5, designing a speed regulator control model. A set of special sequential control flow is designed on a program of a hydropower station computer monitoring system, and the guide vane opening drainage flow is started by monitoring one key, so that the aim of automatically, quickly and safely discharging accumulated water in the drainage tunnel is fulfilled.)

1. A a key is opened guide vane drainage flow for mixed flow hydroelectric set monitored control system, its characterized in that includes the following steps:

step 1, designing starting conditions of a one-key opening guide vane drainage process: after a 'one-key opening guide vane drainage process starting' order is sent out by monitoring, the conditions needing to be judged before the process is started are met, and the process can be started;

step 2, analyzing the operation condition of the unit, determining the sequence and conversion conditions of equipment operation, and drawing a one-key opening guide vane drainage flow chart;

step 3, starting priority setting of a one-key opening guide vane drainage process;

step 4, optimizing the starting conditions of the unit accident shutdown process;

and 5, designing a speed regulator control model.

2. The single-key-opening guide vane drainage process for the mixed-flow water-turbine generator set monitoring system according to claim 1, wherein the monitoring of the starting conditions of the single-key-opening guide vane drainage process in the step 1 comprises:

1) high pressure oil system OK judgment condition: the control mode of the high-pressure oil pump is in a remote position, all control power supplies and power supplies of the high-pressure oil pump are normal, and the oil pump and the pipeline filter of the high-pressure oil system have no differential pressure alarm;

2) the access door of the water inlet is closed completely: after the hydroelectric generating set is overhauled, a quick door is required to keep a certain opening degree and stop water when the access door falls due to the requirement of certain special overhauling work, in order to improve the flexibility of a one-key opening guide vane drainage process, a rhombic forcing button for completely closing the access door at the water inlet of the hydroelectric generating set is arranged in a process starting condition, an operator operates the button on a monitoring system operator station after confirming that the access door of the hydroelectric generating set is completely closed, and a water inlet overhauling state is set so as to meet the starting condition of the one-key opening guide vane drainage process;

3) the water machine backup protection OK judgment condition: the water machine backup protection has no action signal, the power supply of a water machine backup cabinet is normal, the water machine backup protection and the unit quick door falling loop and the optical transceiver are normal, and the water machine PLC operates normally;

4) conditions for judging the shear pin OK: monitoring a shearing signal of a shearing pin of the waterless turbine, wherein a power supply of a shearing pin signal instrument is normal;

5) the OK judgment condition of the speed regulation system is as follows: the control mode of the regulator electrical cabinet is in a remote place, the control mode of the turbine guide vane is in an automatic place, the power supply of the unit rotating speed device is normal, the power supply of the regulator electrical cabinet and the mechanical cabinet is normal, and the regulator does not have serious failure alarm;

6) mechanical brake OK determination conditions: the power supply of the mechanical brake cabinet of the generator is normal, the mechanical brake control mode is in a remote position, and the pressure of a mechanical brake air source is more than 0.5 Mpa;

7) the OK judgment condition of the speed regulator hydraulic system is as follows: the control mode of the hydraulic system of the speed governor is in a remote position, the power supply of a control cabinet of the hydraulic system of the speed governor is normal, the emergency stop button of the speed governor is not pressed, the emergency pressure distribution valve is not put into use, the main oil supply source valve, the emergency oil source valve and the main distribution maintenance valve of the hydraulic system of the speed governor are all opened, the hydraulic system of the speed governor does not give an alarm, the oil level of an oil return tank of the hydraulic system of the speed governor is normal, and the pressure and the oil level of a pressure oil tank of the hydraulic system of the speed governor are normal;

8) and (3) judging conditions of maintenance air seal OK: the maintenance air seal is not pressurized, and the maintenance air seal pressure is less than 0.5 Mpa.

3. The one-key-opening guide vane drainage process for the mixed-flow water-turbine generator set monitoring system according to claim 1, wherein in the step 2, the detailed steps of the one-key-opening guide vane drainage process are as follows:

s1: after receiving the 'one-key opening guide vane drainage process starting' order, the LCU automatically judges whether the one-key opening guide vane drainage process starting condition in the step 1 is met; if so, entering S2, otherwise, exiting the process;

s2: the LCU opens a technical water supply input unit, starts a water guide external circulation oil pump, judges whether a technical water supply pressure reducing valve of the unit is opened or not, enters S3 if the technical water supply pressure reducing valve is opened, and exits if the technical water supply pressure reducing valve is not opened;

s3: judging whether the flow rate of the technical water supply cooling water of the unit meets the requirements, if so, entering S4, and if not, exiting the process;

s4: judging whether the unit water guide external circulation oil pump operates, if so, entering S5, and if not, exiting the process;

s5: judging whether the oil flow of the unit water guide external circulation system is low, if so, exiting the process, and if not, entering S6;

s6: judging whether the oil level of the water guide oil groove of the unit is low, if so, exiting the process, and if not, entering S7;

s7: the LCU opens a starting oil mist absorption device, a starting carbon powder absorption device, a forbidding creep detection and a starting order of a hydraulic system of the speed regulator, judges whether the hydraulic system of the speed regulator operates, and enters S8 if the hydraulic system of the speed regulator operates, and exits if the hydraulic system of the speed regulator does not operate;

s8: judging whether the oil pressure of a pipeline of a hydraulic system of the speed regulator is greater than 6.1Mpa, if so, entering S9, and if not, exiting the process;

s9: judging whether the oil pressure of a hydraulic oil tank of a speed regulator hydraulic system is greater than 6.1Mpa, if so, entering S10, and if not, exiting the process;

s10: judging whether the oil level of a pressure oil tank of a speed regulator hydraulic system is larger than 1200mm, if so, entering S11, and if not, exiting the process;

s11: judging whether the sealing water flow and the pressure of the main shaft of the water turbine are normal or not, if so, entering S12, and if not, exiting the process;

s12: the LCU opens an automatic ingot locking command for pulling out, the automatic ingot locking is not pulled out within 30S, the process automatically exits, and if not, the process enters S13;

s13: the LCU sends a command of starting the high-pressure oil pump, the non-operation process of the 1# or 2# high-pressure oil pump in 120S automatically exits, and if not, the step enters S14;

s14: judging whether the high-pressure oil system is pressed to work, if so, entering S15, and if not, exiting the process;

s15: judging whether all the mechanical braking air brakes fall down, if so, entering S16, and if not, exiting the process;

s16: the LCU opens a guide vane drainage order and enters S17 and S19;

s17: opening the guide vane to drain water within 30min, judging whether the volute and tail water are pressed horizontally or receiving a monitoring manual flat pressing signal, if so, entering S18, and if not, giving an alarm;

s18: judging whether the water is discharged by opening the guide vane within 30min, judging whether the pressure at the inlet of the volute is less than or equal to 0.25Mpa or the pressure at the outlet of the volute is less than or equal to 0.3Mpa, if so, entering S20, otherwise, giving an alarm and entering S20;

s19: judging whether the rotation speed of the unit is less than or equal to 20% within 30min after the guide vane is opened for draining water, if so, entering S20, otherwise, giving an alarm and entering S20;

s20: the LCU opens a speed regulator to stop, and puts a brake dust absorption device to judge whether the guide vane is completely closed, if so, the process enters S21, and if not, the process exits;

s21: judging whether the rotating speed of the unit in 480S after the speed governor is stopped and the speed governor is started is less than or equal to 20%, if so, entering S22, and if not, exiting the process;

s22: the LCU opens a mechanical braking command and judges whether the rotating speed of the unit is 0%, if so, the step enters S23, and if not, the step exits;

s23: the LCU opens an automatic ingot locking and throwing command, judges whether an automatic ingot locking is thrown, if so, enters S24, otherwise, gives an alarm and enters S24;

s24: the LCU starts a water-stopping external circulation oil guide pump and puts a peristaltic device command into the LCU, whether the peristaltic device of the unit has a peristaltic alarm is judged, if yes, the process is exited, and if not, the process enters S25;

s25: the LCU opens and stops the speed regulator hydraulic system, exits the brake dust absorption device, exits the carbon powder absorption device, exits the derived oil mist absorption device, exits the upper guided oil mist absorption device and exits the mechanical brake command, and judges whether the pressure oil pump of the speed regulator hydraulic system is completely stopped, if so, the method enters S26, and if not, the method exits;

s26: judging whether the isolation valve of the hydraulic system of the speed regulator is completely closed, if so, entering S27, and if not, exiting the process;

s27: and judging whether the mechanical braking air brakes fall down completely, if so, entering a water system operation state of the unit, and if not, exiting the process.

4. The one-key-open guide vane drainage process for the mixed-flow water-turbine generator set monitoring system according to claim 1, wherein the specific setting method in the step 3 is as follows:

the hydropower station unit is provided with three accident shutdowns, which are respectively: shutdown in the first class of mechanical accidents, shutdown in the electrical accidents and shutdown in the second class of mechanical accidents; the starting priority set in the LCU program of the unit is as follows: one type of mechanical accident shutdown has the highest priority, the second type of electrical accident shutdown, the second type of mechanical accident shutdown and the last other processes;

according to the principle that the starting priority of the one-key opening guide vane drainage process is lower than that of the accident process, after the one-key opening guide vane drainage process is introduced, the starting priority sequence of each control process of the LCU of the unit is as follows:

one-type mechanical accident shutdown > electrical accident shutdown > two-type mechanical accident shutdown > monitoring one-key opening guide vane drainage flow and other flows.

5. The one-key-open guide vane drainage process for the mixed-flow water-turbine generator set monitoring system according to claim 1, wherein the specific optimization method in the step 4 comprises the following steps: the condition that the starting of the unit accident shutdown process can be caused after the starting of the one-key opening guide vane drainage process is monitored is added with 'one-key opening guide vane drainage process starting' locking, so that the unit accident shutdown process is prevented from being started by mistake.

6. The one-key-open guide vane drainage process for the mixed-flow water-turbine generator set monitoring system according to claim 1, which is characterized in that the specific design method in the step 5 is as follows:

according to the analysis of the manual guide vane opening and drainage operation process and the consideration of the unit rotating speed limiting factor, the speed regulator control model is designed according to three stages:

the first stage is as follows: a rotating speed rising stage: after the speed regulating system receives a 'one-key opening guide vane drainage flow starting' order sent by monitoring, the speed regulator of the left bank unit of the power station automatically opens the guide vanes to 6-10% of the 1 st opening at the speed of 1.3%/min-1.8%/min; the speed regulator of the right bank unit automatically opens the guide vane to 10% -15% of the 1 st opening at the speed of 2.7%/min-3.5%/min, and the maximum rotating speed of the unit is increased to 65%;

and a second stage: maintaining the rotating speed: after the rotating speed of the unit rises to 65%, the speed regulator is switched to the rotating speed as a control target to automatically control and regulate the opening of the guide vane, and when the opening of the guide vane reaches 50% of the maximum opening, the speed regulator stops regulating and maintains the current opening, so that the accumulated water in the diversion tunnel is fully discharged;

and a third stage: adjusting the opening degree of the guide vanes: after the volute and the tail level are monitored and judged to be pressed, a 'speed regulator stop order' is sent to a speed regulating system, and the guide vanes are completely closed within 30 seconds of the speed regulator.

7. The one-key-open guide vane drainage process for the mixed-flow water-turbine generator set monitoring system according to claim 6, wherein the 1 st opening size of the guide vane is influenced by the following factors:

1) length of diversion tunnel;

2) the shutdown time is long;

3) the water leakage of the guide vane is large;

4) the water leakage of the water inlet gate is large and small;

5) and after the unit stops the operation of the water inlet gate, the technical water supply system is stopped.

8. The single-key-open guide vane drainage process for the mixed-flow water-turbine generator set monitoring system according to claim 6, wherein the guide vane operating rate is: the opening rate of each unit guide vane is between 1.3%/min and 5.1%/min;

the highest rotating speed is as follows: the highest rotating speed of the machine set is maintained between 54% and 78% of rated rotating speed in the manual guide vane opening and water discharging process, wherein 43% of the highest rotating speed of the machine set is maintained at about 65%.

9. The one-key-opening guide vane drainage process for the mixed-flow water-turbine generator set monitoring system according to claim 6, wherein in the second stage, when the unit starts to decrease from the highest rotation speed, in order to maintain the rotation speed of the unit and reduce the operation time of the unit in the low rotation speed region, an operator manually adjusts the guide vanes from the 1 st opening degree to the 2 nd opening degree slowly and maintains the 2 nd opening degree for operation for a period of time, wherein the second opening degree is the maximum opening degree of the guide vanes in the manual guide vane opening drainage process.

10. The one-key opening guide vane drainage process for the mixed-flow water-turbine generator set monitoring system according to claim 6, wherein in the third stage, an operator monitors that the pressure of a volute port is close to the pressure of an inlet of a draft tube, judges that the pressure of the volute and the pressure of a tail water level are equal, quickly closes the guide vane from the 2 nd opening to the full closing, and manually puts in a mechanical braking air brake when the rotating speed of the generator set is reduced to 20%.

Technical Field

The invention relates to the technical field of mixed-flow water turbine generator sets, in particular to a one-key opening guide vane drainage process for a mixed-flow water turbine generator set monitoring system.

Background

According to the requirements of safety technical measures of the hydroelectric generating set during maintenance operation, the hydroelectric generating set needs to completely drain accumulated water in the diversion tunnel before maintenance. Because the mixed-flow water turbine generator set has the characteristics of long diversion tunnel, large inner diameter, high water head, large pressure and the like, how to quickly and safely discharge accumulated water in the diversion tunnel becomes an important factor influencing the overhaul period of the set.

At present, the maintenance drainage modes of the mixed-flow water turbine generator set mainly comprise 3 types of water supply drainage, manual guide vane drainage and volute disc valve drainage by using organic group technologies, but the three drainage modes have certain limitations on use conditions.

And supplying water and discharging accumulated water in the diversion tunnel through the unit technology. When the water supply system of the hydroelectric generating set technology adopts a volute water taking mode to supply water, accumulated water in the diversion tunnel can be discharged to tail water through the set technology water supply. The mode is that after a water inlet gate of the unit falls down, accumulated water in the diversion tunnel is discharged to a tail water pipe through related pipelines of unit technology water supply under the action of pressure difference, so that the aim of horizontally pressing the diversion tunnel and the tail is fulfilled. And (3) calculating the water diversion tunnel of a certain power station unit from the beginning of water drainage to the flat pressure state according to the initial calculation, wherein the required time is about 1 day generally. The drainage mode is simple to operate and low in risk, but the longer drainage time severely limits the overhaul period of the unit.

And manually opening the guide vanes to drain water. After the gate of the water inlet of the unit falls down, the guide vane is manually opened on the speed regulator control cabinet, and the rotating speed of the unit is controlled to be maintained at 60-70% in the whole drainage process. The drainage mode has high efficiency, and the diversion tunnel can drain water to be horizontally pressed with the tail in a very short time. However, the water discharge method needs manual control of the rotating speed of the unit, and due to the characteristic difference between different units and different experience of operators, the opening degree and the opening time of the guide vane cannot be optimally controlled, so that the risks of unit overspeed and tile burning exist.

And (4) draining water by using a volute disc type valve. This drainage mode needs the manual snail shell dish type valve of opening, because fill with water in the pressure steel pipe this moment, and water pressure is big, and the operation degree of difficulty of snail shell dish type valve is big, and simultaneously at the drainage in-process, because the impact of high-speed rivers can cause the circumstances such as snail shell dish type valve vibrations, corrosion and cavitation, has risks such as damage dish type valve seal or valve rod fracture. Therefore, opening the volute disc type valve directly to drain water is not suitable for high head power stations.

Disclosure of Invention

The invention aims to provide a one-key guide vane opening drainage process for a mixed-flow type hydroelectric generating set monitoring system, which realizes the purpose of automatically, quickly and safely draining accumulated water in a diversion tunnel by designing a set of special sequential control process on a hydropower station computer monitoring system program and starting the guide vane opening drainage process by monitoring one key.

In order to achieve the technical features, the invention is realized as follows: a a key is opened guide vane drainage flow for mixed flow hydroelectric set monitored control system, its characterized in that includes the following steps:

step 1, designing starting conditions of a one-key opening guide vane drainage process: after a 'one-key opening guide vane drainage process starting' order is sent out by monitoring, the conditions needing to be judged before the process is started are met, and the process can be started;

step 2, analyzing the operation condition of the unit, determining the sequence and conversion conditions of equipment operation, and drawing a one-key opening guide vane drainage flow chart;

step 3, starting priority setting of a one-key opening guide vane drainage process;

step 4, optimizing the starting conditions of the unit accident shutdown process;

and 5, designing a speed regulator control model.

The step 1 of monitoring the starting conditions of the one-key opening guide vane drainage process comprises the following steps:

1) high pressure oil system OK judgment condition: the control mode of the high-pressure oil pump is in a remote position, all control power supplies and power supplies of the high-pressure oil pump are normal, and the oil pump and the pipeline filter of the high-pressure oil system have no differential pressure alarm;

2) the access door of the water inlet is closed completely: after the hydroelectric generating set is overhauled, a quick door is required to keep a certain opening degree and stop water when the access door falls due to the requirement of certain special overhauling work, in order to improve the flexibility of a one-key opening guide vane drainage process, a rhombic forcing button for completely closing the access door at the water inlet of the hydroelectric generating set is arranged in a process starting condition, an operator operates the button on a monitoring system operator station after confirming that the access door of the hydroelectric generating set is completely closed, and a water inlet overhauling state is set so as to meet the starting condition of the one-key opening guide vane drainage process;

3) the water machine backup protection OK judgment condition: the water machine backup protection has no action signal, the power supply of a water machine backup cabinet is normal, the water machine backup protection and the unit quick door falling loop and the optical transceiver are normal, and the water machine PLC operates normally;

4) conditions for judging the shear pin OK: monitoring a shearing signal of a shearing pin of the waterless turbine, wherein a power supply of a shearing pin signal instrument is normal;

5) the OK judgment condition of the speed regulation system is as follows: the control mode of the regulator electrical cabinet is in a remote place, the control mode of the turbine guide vane is in an automatic place, the power supply of the unit rotating speed device is normal, the power supply of the regulator electrical cabinet and the mechanical cabinet is normal, and the regulator does not have serious failure alarm;

6) mechanical brake OK determination conditions: the power supply of the mechanical brake cabinet of the generator is normal, the mechanical brake control mode is in a remote position, and the pressure of a mechanical brake air source is more than 0.5 Mpa;

7) the OK judgment condition of the speed regulator hydraulic system is as follows: the control mode of the hydraulic system of the speed governor is in a remote position, the power supply of a control cabinet of the hydraulic system of the speed governor is normal, the emergency stop button of the speed governor is not pressed, the emergency pressure distribution valve is not put into use, the main oil supply source valve, the emergency oil source valve and the main distribution maintenance valve of the hydraulic system of the speed governor are all opened, the hydraulic system of the speed governor does not give an alarm, the oil level of an oil return tank of the hydraulic system of the speed governor is normal, and the pressure and the oil level of a pressure oil tank of the hydraulic system of the speed governor are normal;

8) and (3) judging conditions of maintenance air seal OK: the maintenance air seal is not pressurized, and the maintenance air seal pressure is less than 0.5 Mpa.

The detailed steps of the water drainage process of opening the guide vane by one key in the step 2 are as follows:

s1: after receiving the 'one-key opening guide vane drainage process starting' order, the LCU automatically judges whether the one-key opening guide vane drainage process starting condition in the step 1 is met; if so, entering S2, otherwise, exiting the process;

s2: the LCU opens a technical water supply input unit, starts a water guide external circulation oil pump, judges whether a technical water supply pressure reducing valve of the unit is opened or not, enters S3 if the technical water supply pressure reducing valve is opened, and exits if the technical water supply pressure reducing valve is not opened;

s3: judging whether the flow rate of the technical water supply cooling water of the unit meets the requirements, if so, entering S4, and if not, exiting the process;

s4: judging whether the unit water guide external circulation oil pump operates, if so, entering S5, and if not, exiting the process;

s5: judging whether the oil flow of the unit water guide external circulation system is low, if so, exiting the process, and if not, entering S6;

s6: judging whether the oil level of the water guide oil groove of the unit is low, if so, exiting the process, and if not, entering S7;

s7: the LCU opens a starting oil mist absorption device, a starting carbon powder absorption device, a forbidding creep detection and a starting order of a hydraulic system of the speed regulator, judges whether the hydraulic system of the speed regulator operates, and enters S8 if the hydraulic system of the speed regulator operates, and exits if the hydraulic system of the speed regulator does not operate;

s8: judging whether the oil pressure of a pipeline of a hydraulic system of the speed regulator is greater than 6.1Mpa, if so, entering S9, and if not, exiting the process;

s9: judging whether the oil pressure of a hydraulic oil tank of a speed regulator hydraulic system is greater than 6.1Mpa, if so, entering S10, and if not, exiting the process;

s10: judging whether the oil level of a pressure oil tank of a speed regulator hydraulic system is larger than 1200mm, if so, entering S11, and if not, exiting the process;

s11: judging whether the sealing water flow and the pressure of the main shaft of the water turbine are normal or not, if so, entering S12, and if not, exiting the process;

s12: the LCU opens an automatic ingot locking command for pulling out, the automatic ingot locking is not pulled out within 30S, the process automatically exits, and if not, the process enters S13;

s13: the LCU sends a command of starting the high-pressure oil pump, the non-operation process of the 1# or 2# high-pressure oil pump in 120S automatically exits, and if not, the step enters S14;

s14: judging whether the high-pressure oil system is pressed to work, if so, entering S15, and if not, exiting the process;

s15: judging whether all the mechanical braking air brakes fall down, if so, entering S16, and if not, exiting the process;

s16: the LCU opens a guide vane drainage order and enters S17 and S19;

s17: opening the guide vane to drain water within 30min, judging whether the volute and tail water are pressed horizontally or receiving a monitoring manual flat pressing signal, if so, entering S18, and if not, giving an alarm;

s18: judging whether the water is discharged by opening the guide vane within 30min, judging whether the pressure at the inlet of the volute is less than or equal to 0.25Mpa or the pressure at the outlet of the volute is less than or equal to 0.3Mpa, if so, entering S20, otherwise, giving an alarm and entering S20;

s19: judging whether the rotation speed of the unit is less than or equal to 20% within 30min after the guide vane is opened for draining water, if so, entering S20, otherwise, giving an alarm and entering S20;

s20: the LCU opens a speed regulator to stop, and puts a brake dust absorption device to judge whether the guide vane is completely closed, if so, the process enters S21, and if not, the process exits;

s21: judging whether the rotating speed of the unit in 480S after the speed governor is stopped and the speed governor is started is less than or equal to 20%, if so, entering S22, and if not, exiting the process;

s22: the LCU opens a mechanical braking command and judges whether the rotating speed of the unit is 0%, if so, the step enters S23, and if not, the step exits;

s23: the LCU opens an automatic ingot locking and throwing command, judges whether an automatic ingot locking is thrown, if so, enters S24, otherwise, gives an alarm and enters S24;

s24: the LCU starts a water-stopping external circulation oil guide pump and puts a peristaltic device command into the LCU, whether the peristaltic device of the unit has a peristaltic alarm is judged, if yes, the process is exited, and if not, the process enters S25;

s25: the LCU opens and stops the speed regulator hydraulic system, exits the brake dust absorption device, exits the carbon powder absorption device, exits the derived oil mist absorption device, exits the upper guided oil mist absorption device and exits the mechanical brake command, and judges whether the pressure oil pump of the speed regulator hydraulic system is completely stopped, if so, the method enters S26, and if not, the method exits;

s26: judging whether the isolation valve of the hydraulic system of the speed regulator is completely closed, if so, entering S27, and if not, exiting the process;

s27: and judging whether the mechanical braking air brakes fall down completely, if so, entering a water system operation state of the unit, and if not, exiting the process.

The specific setting method in the step 3 is as follows:

the hydropower station unit is provided with three accident shutdowns, which are respectively: shutdown in the first class of mechanical accidents, shutdown in the electrical accidents and shutdown in the second class of mechanical accidents; the starting priority set in the LCU program of the unit is as follows: one type of mechanical accident shutdown has the highest priority, the second type of electrical accident shutdown, the second type of mechanical accident shutdown and the last other processes;

according to the principle that the starting priority of the one-key opening guide vane drainage process is lower than that of the accident process, after the one-key opening guide vane drainage process is introduced, the starting priority sequence of each control process of the LCU of the unit is as follows:

one-type mechanical accident shutdown > electrical accident shutdown > two-type mechanical accident shutdown > monitoring one-key opening guide vane drainage flow and other flows.

The specific optimization method in the step 4 comprises the following steps: the condition that the starting of the unit accident shutdown process can be caused after the starting of the one-key opening guide vane drainage process is monitored is added with 'one-key opening guide vane drainage process starting' locking, so that the unit accident shutdown process is prevented from being started by mistake.

The specific design method in the step 5 comprises the following steps:

according to the analysis of the manual guide vane opening and drainage operation process and the consideration of the unit rotating speed limiting factor, the speed regulator control model is designed according to three stages:

the first stage is as follows: a rotating speed rising stage: after the speed regulating system receives a 'one-key opening guide vane drainage flow starting' order sent by monitoring, the speed regulator of the left bank unit of the power station automatically opens the guide vanes to 6-10% of the 1 st opening at the speed of 1.3%/min-1.8%/min; the speed regulator of the right bank unit automatically opens the guide vane to 10% -15% of the 1 st opening at the speed of 2.7%/min-3.5%/min, and the maximum rotating speed of the unit is increased to 65%;

and a second stage: maintaining the rotating speed: after the rotating speed of the unit rises to 65%, the speed regulator is switched to the rotating speed as a control target to automatically control and regulate the opening of the guide vane, and when the opening of the guide vane reaches 50% of the maximum opening, the speed regulator stops regulating and maintains the current opening, so that the accumulated water in the diversion tunnel is fully discharged;

and a third stage: adjusting the opening degree of the guide vanes: after the volute and the tail level are monitored and judged to be pressed, a 'speed regulator stop order' is sent to a speed regulating system, and the guide vanes are completely closed within 30 seconds of the speed regulator.

The 1 st opening size of the guide vane is influenced by the following factors:

1) length of diversion tunnel;

2) the shutdown time is long;

3) the water leakage of the guide vane is large;

4) the water leakage of the water inlet gate is large and small;

5) and after the unit stops the operation of the water inlet gate, the technical water supply system is stopped.

The guide vane operating rate: the opening rate of each unit guide vane is between 1.3%/min and 5.1%/min;

the highest rotating speed is as follows: the highest rotating speed of the machine set is maintained between 54% and 78% of rated rotating speed in the manual guide vane opening and water discharging process, wherein 43% of the highest rotating speed of the machine set is maintained at about 65%.

And in the second stage, when the unit starts to descend from the highest rotating speed, in order to maintain the rotating speed of the unit and reduce the running time of the unit in a low rotating speed area, an operator manually and slowly adjusts the guide vane from the 1 st opening to the 2 nd opening and maintains the 2 nd opening to run for a period of time, wherein the second opening is the maximum guide vane opening in the manual guide vane opening water drainage process.

In the third stage, an operator monitors that the pressure of a volute opening is close to the pressure of an inlet of a draft tube, quickly closes the guide vane from the opening 2 to full-closed after judging that the volute and the draft tube are horizontally pressed, and manually puts into a mechanical brake when the rotating speed of the unit is reduced to 20%.

The invention has the beneficial effects that:

1. according to the invention, the manual guide vane opening and drainage operation steps are streamlined, and the automatic guide vane opening and drainage of the process is realized through the monitoring system, so that the operation amount and the operation risk of plant station operators are reduced.

2. The invention overcomes the defects that the optimal guide vane opening time and the optimal guide vane opening degree cannot be mastered necessarily due to different experience and different operation methods of operators in the manual guide vane opening and water discharging operation process, the damage degree to equipment is different, and the damage to the equipment in the guide vane opening and water discharging process can be reduced to the minimum through automatic process operation.

3. By adopting the one-key opening guide vane drainage flow, the action time is short, the overhaul period of the unit can be shortened, the available hours of the unit can be increased, and more economic benefits can be created for a power plant.

Drawings

The invention is further illustrated by the following figures and examples.

FIG. 1 is a first partial flow diagram of the drainage process of the present invention.

FIG. 2 is a flow diagram illustrating a second portion of the drainage process of FIG. 1.

FIG. 3 is a flow diagram illustrating a second portion of the drainage process of FIG. 2 according to the present invention.

FIG. 4 is a diagram showing conditions for starting the drainage process of the present invention.

FIG. 5 is a diagram of optimization of the start conditions of the unit accident shutdown process of the present invention.

Detailed Description

Embodiments of the present invention will be further described with reference to the accompanying drawings.

Referring to fig. 1-5, a one-key-open guide vane drainage process for a mixed flow type hydroelectric generating set monitoring system is characterized by comprising the following steps:

step 1, designing starting conditions of a one-key opening guide vane drainage process: after a 'one-key opening guide vane drainage process starting' order is sent out by monitoring, the conditions needing to be judged before the process is started are met, and the process can be started;

the method comprises the steps of analyzing control modes and state parameters which need to be possessed by a unit and auxiliary equipment thereof before a one-key-on guide vane drainage process is started, using the control modes and the state parameter measuring points which need to be possessed by the one-key-on guide vane drainage process which is acquired by a unit LCU as starting conditions of the process after certain logic configuration, monitoring and issuing a 'one-key-on guide vane drainage process starting' order, automatically judging whether the starting conditions are met by the LCU at first, meeting the rear starting process, and preventing equipment damage and accidents caused by the condition being not met.

Referring specifically to fig. 4, monitoring the starting conditions of the one-key-opened guide vane drainage process includes:

1) high pressure oil system OK judgment condition: the control mode of the high-pressure oil pump is in a remote position, all control power supplies and power supplies of the high-pressure oil pump are normal, and the oil pump and the pipeline filter of the high-pressure oil system have no differential pressure alarm;

2) the access door of the water inlet is closed completely: after the hydroelectric generating set is overhauled, a quick door is required to keep a certain opening degree and stop water when the access door falls due to the requirement of certain special overhauling work, in order to improve the flexibility of a one-key opening guide vane drainage process, a rhombic forcing button for completely closing the access door at the water inlet of the hydroelectric generating set is arranged in a process starting condition, an operator operates the button on a monitoring system operator station after confirming that the access door of the hydroelectric generating set is completely closed, and a water inlet overhauling state is set so as to meet the starting condition of the one-key opening guide vane drainage process;

3) the water machine backup protection OK judgment condition: the water machine backup protection has no action signal, the power supply of a water machine backup cabinet is normal, the water machine backup protection and the unit quick door falling loop and the optical transceiver are normal, and the water machine PLC operates normally;

4) conditions for judging the shear pin OK: monitoring a shearing signal of a shearing pin of the waterless turbine, wherein a power supply of a shearing pin signal instrument is normal;

5) the OK judgment condition of the speed regulation system is as follows: the control mode of the regulator electrical cabinet is in a remote place, the control mode of the turbine guide vane is in an automatic place, the power supply of the unit rotating speed device is normal, the power supply of the regulator electrical cabinet and the mechanical cabinet is normal, and the regulator does not have serious failure alarm;

6) mechanical brake OK determination conditions: the power supply of the mechanical brake cabinet of the generator is normal, the mechanical brake control mode is in a remote position, and the pressure of a mechanical brake air source is more than 0.5 Mpa;

7) the OK judgment condition of the speed regulator hydraulic system is as follows: the control mode of the hydraulic system of the speed governor is in a remote position, the power supply of a control cabinet of the hydraulic system of the speed governor is normal, the emergency stop button of the speed governor is not pressed, the emergency pressure distribution valve is not put into use, the main oil supply source valve, the emergency oil source valve and the main distribution maintenance valve of the hydraulic system of the speed governor are all opened, the hydraulic system of the speed governor does not give an alarm, the oil level of an oil return tank of the hydraulic system of the speed governor is normal, and the pressure and the oil level of a pressure oil tank of the hydraulic system of the speed governor are normal;

8) and (3) judging conditions of maintenance air seal OK: the maintenance air seal is not pressurized, and the maintenance air seal pressure is less than 0.5 Mpa.

Step 2, analyzing the operation condition of the unit, determining the sequence and conversion conditions of equipment operation, and drawing a one-key opening guide vane drainage flow chart;

combining with field equipment to comb out the sequence and conversion condition of the object to be controlled in the execution process of the one-key opening guide vane drainage process, wherein the conversion condition refers to the condition of process alarm or exit caused by the fact that the equipment state does not meet the requirement in the execution process of the conversion process, and drawing a one-key opening guide vane drainage process diagram according to the sequence and conversion condition of equipment operation.

Referring to fig. 1-3, the detailed steps of the one-key opening guide vane drainage process are as follows:

s1: after receiving the 'one-key opening guide vane drainage process starting' order, the LCU automatically judges whether the one-key opening guide vane drainage process starting condition in the step 1 is met; if so, entering S2, otherwise, exiting the process;

s2: the LCU opens a technical water supply input unit, starts a water guide external circulation oil pump, judges whether a technical water supply pressure reducing valve of the unit is opened or not, enters S3 if the technical water supply pressure reducing valve is opened, and exits if the technical water supply pressure reducing valve is not opened;

s3: judging whether the flow rate of the technical water supply cooling water of the unit meets the requirements, if so, entering S4, and if not, exiting the process;

s4: judging whether the unit water guide external circulation oil pump operates, if so, entering S5, and if not, exiting the process;

s5: judging whether the oil flow of the unit water guide external circulation system is low, if so, exiting the process, and if not, entering S6;

s6: judging whether the oil level of the water guide oil groove of the unit is low, if so, exiting the process, and if not, entering S7;

s7: the LCU opens a starting oil mist absorption device, a starting carbon powder absorption device, a forbidding creep detection and a starting order of a hydraulic system of the speed regulator, judges whether the hydraulic system of the speed regulator operates, and enters S8 if the hydraulic system of the speed regulator operates, and exits if the hydraulic system of the speed regulator does not operate;

s8: judging whether the oil pressure of a pipeline of a hydraulic system of the speed regulator is greater than 6.1Mpa, if so, entering S9, and if not, exiting the process;

s9: judging whether the oil pressure of a hydraulic oil tank of a speed regulator hydraulic system is greater than 6.1Mpa, if so, entering S10, and if not, exiting the process;

s10: judging whether the oil level of a pressure oil tank of a speed regulator hydraulic system is larger than 1200mm, if so, entering S11, and if not, exiting the process;

s11: judging whether the sealing water flow and the pressure of the main shaft of the water turbine are normal or not, if so, entering S12, and if not, exiting the process;

s12: the LCU opens an automatic ingot locking command for pulling out, the automatic ingot locking is not pulled out within 30S, the process automatically exits, and if not, the process enters S13;

s13: the LCU sends a command of starting the high-pressure oil pump, the non-operation process of the 1# or 2# high-pressure oil pump in 120S automatically exits, and if not, the step enters S14;

s14: judging whether the high-pressure oil system is pressed to work, if so, entering S15, and if not, exiting the process;

s15: judging whether all the mechanical braking air brakes fall down, if so, entering S16, and if not, exiting the process;

s16: the LCU opens a guide vane drainage order and enters S17 and S19;

s17: opening the guide vane to drain water within 30min, judging whether the volute and tail water are pressed horizontally or receiving a monitoring manual flat pressing signal, if so, entering S18, and if not, giving an alarm;

s18: judging whether the water is discharged by opening the guide vane within 30min, judging whether the pressure at the inlet of the volute is less than or equal to 0.25Mpa or the pressure at the outlet of the volute is less than or equal to 0.3Mpa, if so, entering S20, otherwise, giving an alarm and entering S20;

s19: judging whether the rotation speed of the unit is less than or equal to 20% within 30min after the guide vane is opened for draining water, if so, entering S20, otherwise, giving an alarm and entering S20;

s20: the LCU opens a speed regulator to stop, and puts a brake dust absorption device to judge whether the guide vane is completely closed, if so, the process enters S21, and if not, the process exits;

s21: judging whether the rotating speed of the unit in 480S after the speed governor is stopped and the speed governor is started is less than or equal to 20%, if so, entering S22, and if not, exiting the process;

s22: the LCU opens a mechanical braking command and judges whether the rotating speed of the unit is 0%, if so, the step enters S23, and if not, the step exits;

s23: the LCU opens an automatic ingot locking and throwing command, judges whether an automatic ingot locking is thrown, if so, enters S24, otherwise, gives an alarm and enters S24;

s24: the LCU starts a water-stopping external circulation oil guide pump and puts a peristaltic device command into the LCU, whether the peristaltic device of the unit has a peristaltic alarm is judged, if yes, the process is exited, and if not, the process enters S25;

s25: the LCU opens and stops the speed regulator hydraulic system, exits the brake dust absorption device, exits the carbon powder absorption device, exits the derived oil mist absorption device, exits the upper guided oil mist absorption device and exits the mechanical brake command, and judges whether the pressure oil pump of the speed regulator hydraulic system is completely stopped, if so, the method enters S26, and if not, the method exits;

s26: judging whether the isolation valve of the hydraulic system of the speed regulator is completely closed, if so, entering S27, and if not, exiting the process;

s27: and judging whether the mechanical braking air brakes fall down completely, if so, entering a water system operation state of the unit, and if not, exiting the process.

Step 3, starting priority setting of a one-key opening guide vane drainage process;

because the related control flows of the unit in the monitoring system are numerous, in order to prevent the situations that two or more flows are executed simultaneously to interfere with each other and compete for the control right and the like of the same control object, a priority level needs to be set for a one-key opening guide vane drainage flow, the execution of a low-level flow needs to be stopped for a high-level flow, and the starting of a low-level flow needs to be locked for a high-priority flow. The priority setting for monitoring the starting of the one-key opening guide vane drainage process is lower than the electrical accident and mechanical accident process of the unit, and the design aims to monitor that the accident shutdown process can be started in time to avoid the expansion of the accident when the accidents such as unit overspeed, abnormal tile temperature rise and the like occur in the execution process of the one-key opening guide vane drainage process.

The specific setting method in the step 3 is as follows:

the hydropower station unit is provided with three accident shutdowns, which are respectively: shutdown in the first class of mechanical accidents, shutdown in the electrical accidents and shutdown in the second class of mechanical accidents; the starting priority set in the LCU program of the unit is as follows: one type of mechanical accident shutdown has the highest priority, the second type of electrical accident shutdown, the second type of mechanical accident shutdown and the last other processes;

according to the principle that the starting priority of the one-key opening guide vane drainage process is lower than that of the accident process, after the one-key opening guide vane drainage process is introduced, the starting priority sequence of each control process of the LCU of the unit is as follows:

one-type mechanical accident shutdown > electrical accident shutdown > two-type mechanical accident shutdown > monitoring one-key opening guide vane drainage flow and other flows.

Step 4, optimizing the starting conditions of the unit accident shutdown process;

the method is characterized in that conditions of mutual influence of starting conditions of the one-key opening guide vane drainage process and the unit accident shutdown process are combed, necessary interlocking logic is set, and the unit accident shutdown process is prevented from being started by mistake after the one-key opening guide vane drainage process is started. For example, when the motive power of the water turbine is not enough to maintain 100% of the rated rotating speed in the one-key opening guide vane drainage process, a serious fault signal is reported by the speed regulating system, and the one-key opening guide vane drainage process is stopped to start an accident shutdown process, so that drainage failure is caused.

Therefore, the condition that the starting of the unit accident shutdown process can be caused after the monitoring of the starting of the one-key opening guide vane drainage process is added with the 'one-key opening guide vane drainage process starting' locking, so that the unit accident shutdown process is prevented from being started by mistake.

And 5, designing a speed regulator control model.

The method is characterized in that 7 mixed-flow water turbine generator sets are used for discharging accumulated water in a diversion tunnel and a volute in a manual guide vane opening and drainage mode since a certain hydropower station is put into operation, statistical analysis is carried out on 4 sets of characteristic data change trends of guide vane opening, unit rotating speed, volute inlet pressure and draft tube inlet pressure in the manual guide vane opening and drainage process at each time, and meanwhile, a one-key guide vane drainage flow speed regulator control model is obtained through comprehensive analysis by combining unit vibration and swing, bearing bush temperature, cooling water flow and inspection conditions of maintainers on the diversion tunnel during maintenance in the drainage process.

Because mixed-flow hydroelectric set diversion tunnel is long, opens the guide vane drainage after the unit water inlet gate falls down, and if the guide vane aperture change is too fast in the guide vane opening stage, diversion tunnel can experience a full flow to the process of free flow transition, and diversion tunnel can pass through the internal pressure loss of air vent internal entrainment gas replenishment diversion tunnel at this in-process, and the air vent wind speed also can reach the peak value. After the diversion tunnel forms stable free flow, the wind speed of air vent can drop rapidly, if air vent tonifying qi speed is not enough, the rivers that flow out fast can form the negative pressure in the diversion tunnel, and the diversion tunnel is because pressure variation is great, can take place to collapse, fall phenomenons such as piece.

According to the inspection condition of the diversion tunnel of the manually opened guide vane drainage unit during the year of the power station unit, the major defect types of the diversion tunnel are found to be leakage points, leakage cracks, holes and surface damages, and major defects influencing the normal operation of the diversion tunnel are not found. Therefore, in the manual guide vane opening and water discharging operation process, the air replenishing speed of the quick door air vent is enough to offset the negative pressure formed by the water flow which flows out quickly in the unit water diversion tunnel and the volute.

Analyzing historical data of unit vibration and oscillation, bearing bush temperature and cooling water flow in the manual guide vane opening and water discharging process of the power station unit, and finding that vibration, oscillation degree and pressure pulsation values of all parts of the unit are lower than alarm limit values in the water discharging process, so that stable operation conditions are met; the temperature rise of the three bearings of the unit is far lower than an alarm value in the drainage process, the cooling water flow of the unit is enough to meet the cooling requirement of the bearing bush, and the technical water supply source switching of the drainage unit is not needed before drainage operation.

The analysis of the manual guide vane opening and water discharging operation process of each unit shows that the power station unit is higher than the right bank unit in total time from the operation of the guide vanes to the horizontal pressure of the volute and the tail, but the total time of the left bank unit is not more than 30min, and the time of the volute and the tail horizontal pressure of the unit is 2 min-5 min longer than the rotation time of the unit.

Based on this, according to the analysis of manual opening guide vane drainage operation process and the consideration of unit rotational speed limiting factor, speed regulator control model designs according to three stages:

the first stage is as follows: a rotating speed rising stage: after the speed regulating system receives a 'one-key opening guide vane drainage flow starting' order sent by monitoring, the speed regulator of the left bank unit of the power station automatically opens the guide vanes to 6-10% of the 1 st opening at the speed of 1.3%/min-1.8%/min; the speed regulator of the right bank unit automatically opens the guide vane to 10% -15% of the 1 st opening at the speed of 2.7%/min-3.5%/min, and the maximum rotating speed of the unit is increased to 65%;

and a second stage: maintaining the rotating speed: after the rotating speed of the unit rises to 65%, the speed regulator is switched to the rotating speed as a control target to automatically control and regulate the opening of the guide vane, and when the opening of the guide vane reaches 50% of the maximum opening, the speed regulator stops regulating and maintains the current opening, so that the accumulated water in the diversion tunnel is fully discharged;

and a third stage: adjusting the opening degree of the guide vanes: after the volute and the tail level are monitored and judged to be pressed, a 'speed regulator stop order' is sent to a speed regulating system, and the guide vanes are completely closed within 30 seconds of the speed regulator.

The 1 st opening size of the guide vane is influenced by the following factors:

1) length of diversion tunnel;

2) the shutdown time is long;

3) the water leakage of the guide vane is large;

4) the water leakage of the water inlet gate is large and small;

5) and after the unit stops the operation of the water inlet gate, the technical water supply system is stopped.

The guide vane operating rate: the opening rate of each unit guide vane is between 1.3%/min and 5.1%/min;

the highest rotating speed is as follows: the highest rotating speed of the machine set is maintained between 54% and 78% of rated rotating speed in the manual guide vane opening and water discharging process, wherein 43% of the highest rotating speed of the machine set is maintained at about 65%.

And in the second stage, when the unit starts to descend from the highest rotating speed, in order to maintain the rotating speed of the unit and reduce the running time of the unit in a low rotating speed area, an operator manually and slowly adjusts the guide vane from the 1 st opening to the 2 nd opening and maintains the 2 nd opening to run for a period of time, wherein the second opening is the maximum guide vane opening in the manual guide vane opening water drainage process.

This operation is mainly due to the following two considerations:

1) the unit operates in a high-rotation-speed area, so that oil wedges among the bearing bushes can be formed, and the lubricating effect of the bearing bushes can be improved;

2) ensuring that the residual water in the diversion tunnel and the volute is fully discharged.

In the third stage, an operator monitors that the pressure of a volute opening is close to the pressure of an inlet of a draft tube, quickly closes the guide vane from the opening 2 to full-closed after judging that the volute and the draft tube are horizontally pressed, and manually puts into a mechanical brake when the rotating speed of the unit is reduced to 20%.