Pumped storage unit phase modulation water pressing control system and control method thereof

Abstract

The invention discloses a pumped storage unit phase modulation pressurized water control system and a control method thereof.According to the pumped storage unit phase modulation pressurized water control system, a pressurized water air supply system, a water level control system, an exhaust system and a unit starting control system are introduced, and efficient operation of a unit under different working conditions is achieved. By injecting high-pressure gas into the runner chamber, the system can effectively reduce the power requirement when the unit is started, and the impact on a power grid is reduced; meanwhile, by monitoring and adjusting the water level of the runner chamber in real time, stable operation of the unit under the phase modulation working condition is ensured, and the adjusting range of reactive power is greatly enlarged. In addition, the exhaust system can automatically exhaust compressed air in the runner chamber after the unit reaches the rated rotating speed, so that the unit is quickly transited to a normal water pumping operation state, and the overall operation efficiency is improved.

Description

Technical Field

[0001] The present invention belongs to the field of phase-adjusting water pressure control of a pumped storage unit, and in particular, relates to a phase-adjusting water pressure control system and a control method thereof. Background Art

[0002] In traditional pumped storage units, a large amount of starting power is usually consumed when the unit is started. Especially in the case of water pump operation, the water pump needs to overcome a large water resistance when starting. This requires the unit to draw a large amount of electricity from the power grid, resulting in a significant instantaneous impact on the power grid. This impact will not only affect the stability of the power grid, which may cause voltage fluctuations, but may also cause frequency fluctuations in the power grid, thereby affecting the normal operation of other equipment. To alleviate this problem, it is often necessary to introduce additional regulating devices into the power grid or take complex control measures, but these solutions are usually costly and difficult to completely eliminate the impact.

[0003] In addition, in the phase adjustment condition of the unit, in order to ensure that the unit can provide sufficient reactive power adjustment range to stabilize the grid voltage, the air pressure and water level inside the unit need to be regulated within a precise range. However, the water level and air pressure control of the traditional system relies on relatively simple switches or manual control, which has poor accuracy, making the system prone to excessive water level or insufficient air pressure. If the water level is too high, the resistance in the runner chamber will increase, affecting the operating efficiency of the unit and increasing energy consumption; while if the air pressure is too low, the runner will not be able to rotate in the air, thereby weakening the reactive power regulation ability. This unstable operating state not only affects the efficiency of the unit, but also causes the equipment to frequently bear pressure exceeding the design load, thereby increasing the wear and failure risk of the equipment, and ultimately shortening the service life of the unit.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a phase-adjusting water pressure control system and a control method thereof for a pumped storage unit, which solves the problems raised in the above-mentioned background technology.

[0006] In order to solve the above technical problems, the basic concept of the technical solution adopted by the present invention is:

[0007] A phase-adjusting water pressure control system for a pumped storage unit includes: a water pressure and air supply system, which is used to inject high-pressure gas into the runner chamber during the operation of the unit, reduce the water level in the runner chamber, make the runner rotate in the air, reduce the starting power of the unit, and minimize the active power of the unit under the phase-adjusting condition, and increase the reactive power adjustment range;

[0008] A water level control system, which monitors the water level in the tailwater pipe in real time and controls the water level in the runner chamber to maintain it at a predetermined position below the runner, so that the unit can operate safely under different operating conditions;

[0009] An exhaust system, the exhaust system comprising a runner chamber exhaust valve, which is used to gradually exhaust the compressed air in the runner chamber after the unit speed reaches the rated value, so that the pressure in the runner chamber is restored to a condition that allows the unit to pump water;

[0010] The unit start-up control system is responsible for automatically controlling the operation of the water pressure and air supply system and the exhaust system when the unit water pump is started, so that the unit can be safely started under low power state; the unit start-up control system can receive input signals from multiple sensors and control devices, and the input signals include: volute exhaust valve fully open, volute exhaust valve fully closed signal; bottom ring drainage return pipeline valve fully open, bottom ring drainage return pipeline valve fully closed signal; top cover drainage return pipeline valve fully open, top cover drainage return pipeline valve fully closed signal; volute circulation pipeline valve fully open, volute circulation pipeline valve fully closed signal; leak-proof ring water supply valve fully open, leak-proof ring water supply valve fully closed signal; phase-adjusting pressure air valve fully open, phase-adjusting pressure air valve fully closed signal; phase-adjusting air supply valve fully open, phase-adjusting air supply valve fully closed signal; tailwater pipe water level high, medium and low signals. The system's operating logic is automatically executed according to the status of the input signal, including: when the water level in the tailwater pipe is too high, the phase-adjusting air pressure valve and the air supply valve are automatically closed to reduce the air pressure; when the water level in the tailwater pipe is too low, the phase-adjusting air supply valve is automatically opened to replenish gas; when the unit is started, the water pressure and air supply system is controlled to gradually lower the water level, and the air pressure in the runner chamber is adjusted through the exhaust system.

[0011] The unit status monitoring system receives and processes input signals from multiple sensors, and automatically adjusts the working status of the compressed water supply system and the exhaust system based on the input signals. It is used to automatically generate control instructions according to the input signals, and the control instructions include: controlling the opening and closing of the volute exhaust valve; controlling the opening and closing of the bottom ring exhaust return pipeline valve; controlling the opening and closing of the top cover exhaust return pipeline valve; controlling the opening and closing of the volute circulation pipeline valve; controlling the opening and closing of the leak-proof ring water supply valve;

[0012] Optionally, the pressurized water and air supply system includes a phase-adjusting pressure air valve for adjusting the air pressure during phase-adjusting conditions; a phase-adjusting air supply valve for replenishing the air pressure when needed, the exhaust system includes a volute exhaust valve for controlling the discharge of gas from the runner chamber; a bottom ring exhaust return pipeline valve for exhausting and draining at the bottom ring; a top cover exhaust return pipeline valve for exhausting and draining at the top cover, the water level control system includes a tailwater pipe water level sensor for monitoring the water level in the tailwater pipe and providing high, medium and low water level status signals; a leak-proof ring water supply valve for controlling the water supply to the leak-proof ring to ensure the sealing of the unit, and the input signals of the unit status monitoring system include the status of the volute exhaust valve, the status of the bottom ring drain return pipeline valve, the status of the tailwater pipe water level, and also includes a volute circulation pipeline valve for controlling the switching status of the circulation pipeline valve at the volute, thereby regulating the circulation flow in the system.

[0013] Optionally, during the air pressure regulation process, the pressurized water and air supply system will be controlled based on fuzzy logic to dynamically adjust the air pressure injection amount in the pressurized water and air supply system according to the real-time monitored water level, air pressure and speed data, so as to stabilize the water level in the impeller chamber and avoid excessive or insufficient air pressure injection, thereby optimizing the performance of the unit during water pump startup and phase adjustment operation.

[0014] Optionally, the steps of using fuzzy logic control to adjust the air pressure are:

[0015] Obtain the water level in the runner room, the air pressure in the water-pressure air supply system, and the speed of the unit and convert the collected continuous input data into fuzzy sets. Then, a fuzzy rule base is established based on historical data, where each rule contains conditions and corresponding control strategies.

[0016] The fuzzy inference engine infers the fuzzy results of water level, air pressure and speed based on real-time input data and fuzzy rule base to obtain fuzzy output. Subsequently, the fuzzy output is defuzzified to generate a specific air pressure regulation control quantity, which is used to indicate the increase or decrease of air pressure in the water pressure and air supply system;

[0017] According to the defuzzified control quantity, the air pressure injection amount of the pressurized water and air supply system is adjusted in real time. According to the adjusted water level, air pressure and speed changes, real-time monitoring and feedback are carried out to continuously optimize the air pressure injection strategy, so that the water level in the runner chamber is maintained within the predetermined range, and the energy consumption and performance under unit startup and phase adjustment conditions are optimized.

[0018] Optionally, a particle swarm optimization algorithm can be used to establish and train an optimization model based on historical data according to grid demand, the current operating status of the unit, and the pump load. The optimization model can be used to dynamically optimize the output parameters of active and reactive power to ensure that the minimum value of active power is maintained while meeting grid demand and increasing the adjustment range of reactive power.

[0019] Optionally, the steps of dynamically optimizing the output parameters of active and reactive power using a particle swarm optimization algorithm are:

[0020] Get the current operating status parameters of the unit, including the water pump load, grid demand, active power and reactive power initial values. Then, in the optimization model, initialize the particle swarm. The particles represent different output combinations of active power and reactive power. Each particle carries the output value of active power and reactive power. Then, set the optimization goal, that is, reduce the active power output value and expand the reactive power adjustment range while meeting the grid demand. Finally, construct the fitness function. To measure the performance of each power combination, where P target is the active power currently required by the power grid, P output is the current active power output value of the unit, Q output is the current reactive power output value of the unit, Q max is the maximum reactive power output value allowed by the unit, w1 and w2 are weight coefficients used to balance the goals of minimizing active power and maximizing reactive power;

[0021] Assign an initial position and speed to each particle. The position represents the initial output value of active and reactive power, and the speed represents the moving speed of each particle in the power combination space. Then, randomly generate multiple particles, initialize all particles in the population, and calculate the fitness value of each particle.

[0022] According to the historical optimal position and global optimal position of each particle, the speed of each particle is updated, and its expression is: i (t+1)=w·v i (t)+c1·r1·(p best，i -x i (t))+c2·r2·(g best -x i (t)) where v i (t+1) is the velocity of the particle in the next iteration, w is the inertia weight, c1 and c2 are acceleration factors, r1 and r2 are random numbers, p best，i is the historical optimal position of particle i, g best is the global optimal position, x i (t) is the position of particle i at time t. Then, the updated velocity is used to adjust the position of the particle, that is, the active power and reactive power output values, which are expressed as: i (t+1)=x i (t)+v i (t+1), where x i (t+1) is the new power output combination of particle i at time t+1;

[0023] After adjusting the position of the particle, calculate the fitness value of each particle in the new position, compare the current fitness of each particle with the historical best fitness, and update the optimal position of the particle. At the same time, compare the fitness values ​​of all particles, update the global optimal position, and ensure that the global optimal active power and reactive power output combination is found. Then, determine whether the stop condition is met. The stop condition includes that the number of iterations reaches the preset value or the fitness change of the global optimal solution is less than the set threshold. If the stop condition is met, output the global optimal active power and reactive power combination as the power output parameter of the unit. Finally, according to the optimal power output combination obtained by the particle swarm optimization algorithm, adjust the active and reactive power output of the unit to ensure that the active power is maintained at a low value and maximize the reactive power adjustment range while meeting the grid demand. Finally, monitor the changes in grid demand in real time, and continuously adjust the active and reactive power output based on the particle swarm optimization algorithm.

[0024] Optionally, the unit status monitoring system receives and processes input signals from multiple sensors, and automatically adjusts the working status of the pressurized water and air supply system and the exhaust system based on the input signals in the following steps:

[0025] First, by analyzing the collected signals, the current operating status of the unit is evaluated to determine whether the unit is in different operating modes such as water pump working condition, phase adjustment working condition or shutdown. Then, the preset operating parameters are compared with the analysis results and the preset operating parameters to determine whether the unit operating status needs to be adjusted. Then, according to the operating status of the unit and the monitoring results of the tailwater pipe water level, the operation of the pressurized water and air supply system is automatically adjusted. When the water level is lower than the preset value, the pressurized water and air supply system is controlled to open the air supply valve to increase the high-pressure gas injection to reduce the water volume in the runner chamber; when the water level is higher than the preset value, the air supply valve is closed to reduce the air pressure injection to ensure the water level stability. Then, based on the status of the volute exhaust valve and the bottom ring drainage return pipeline valve, the working status of the exhaust system is controlled. When the pressure in the runner chamber needs to be reduced, the volute exhaust valve and the bottom ring drainage return pipeline valve are opened to discharge excess gas; when the appropriate pressure is reached, the exhaust valve is closed to maintain the appropriate operating pressure.

[0026] A method for applying a phase-adjusting water pressure control system of a pumped storage unit includes a water pressure process control method, and the water pressure process control method includes the following steps:

[0027] First, close the volute exhaust valve to prevent air from escaping from the volute part and ensure that the system can effectively accumulate air pressure. Next, close the volute circulation pipeline valve to cut off the gas circulation path in the volute and ensure that the gas can act on the runner chamber. Then, close the bottom ring exhaust return pipeline valve to prevent gas or water leakage at the bottom ring and ensure that the water level in the runner chamber is reduced as expected. Finally, close the top cover exhaust return pipeline valve to cut off the exhaust and drainage pipelines at the top cover to prevent unexpected water or gas flow.

[0028] Open the electric valve for water supply to the stop ring and start injecting water into the stop ring to ensure the tightness of the system. This operation is to prevent gas from leaking from outside the unit during the subsequent injection process and ensure that the system can maintain effective gas pressure regulation;

[0029] Open the phase-adjusting air pressure valve and start injecting high-pressure gas into the runner chamber to gradually lower the water level in the runner chamber until the water level continues to drop to the predetermined target position. This is to reduce water resistance and power consumption during startup.

[0030] In order to lower the water level more quickly and steadily, open the phase-adjusting air supply valve and continuously inject additional gas. The operation of the air supply valve can improve the efficiency of gas injection and ensure that the water level can reach the required low level more quickly;

[0031] The system continuously monitors the water level changes in the tailwater pipe to ensure that the water level is adjusted within a reasonable range. If the tailwater pipe water level fails to drop to the set low level as expected, the system will proceed to the next step based on the feedback information;

[0032] If the water level does not reach the set low level, the system will start the timer. If the water level still does not reach the set low level within the specified time, the system will start the second water pressure operation and re-inject high-pressure gas.

[0033] When it is monitored that the water level in the tailwater pipe has reached the set low level, the phase-adjusting pressure valve and the phase-adjusting air supply valve are immediately closed to stop further gas injection. This prevents the water level from dropping excessively or the air pressure from being too high, ensuring that the system is in a stable state and ready to enter the next operation stage.

[0034] A phase-adjusting water pressure control system and a control method for a pumped storage unit, further comprising an exhaust process control method, the exhaust process control method comprising the following steps:

[0035] First, close the volute circulation pipeline valve to cut off the gas circulation path inside the volute to ensure that there is no gas backflow during the exhaust process. Next, close the phase-adjusting pressure valve to stop any additional gas injection to ensure that the air pressure in the runner chamber does not increase. Then, close the phase-adjusting air supply valve to prevent the system from continuing to inject gas during the exhaust stage, so that the exhaust process can proceed smoothly.

[0036] Open the volute exhaust valve to start discharging compressed gas from the runner chamber, gradually reducing the air pressure in the runner chamber. This operation is to ensure that the air can be discharged smoothly, so that the air pressure in the runner chamber returns to a range suitable for normal operation, and avoid affecting the stable operation of the unit due to excessive air pressure;

[0037] At the same time, open the top cover drainage return pipe valve to let the excess water at the top cover flow into the drainage pipe to prevent the water level in the runner chamber from being too high, which will affect the normal exhaust and operation. Next, open the bottom ring exhaust return pipe valve to continue to discharge the remaining water through the exhaust pipe of the bottom ring to further reduce the water level in the runner chamber and ensure that the water level in the system returns to normal.

[0038] The system sets a delay time to ensure that the exhaust operation is completed smoothly within the specified time. If the system fails to complete the exhaust within the preset time, it may be necessary to re-evaluate the exhaust strategy or check the equipment status to ensure smooth operation;

[0039] The system will detect whether the secondary splashing power has been reached, or monitor whether the water level in the tailwater pipe is too high. If the system detects that the unit has reached the set secondary splashing power, or the water level in the tailwater pipe is too high, the system will automatically terminate the exhaust process to prevent further exhaust operations from affecting the stability of the system.

[0040] Close the drain and exhaust valves: When the exhaust and drainage process is completed, first close the top cover drain return pipe valve to prevent water from continuing to flow into the drainage pipe, then close the bottom ring exhaust return pipe valve to ensure that the bottom ring drainage and exhaust paths are completely closed, thereby stabilizing the water level in the runner chamber;

[0041] End the exhaust operation: completely close the volute exhaust valve, end the entire exhaust operation, ensure that the air pressure in the runner chamber returns to normal levels, and the system smoothly enters the normal operation mode, ready to perform the next operation;

[0042] Close the leak-proof ring water supply valve: When the exhaust and drainage operations are completed and the system enters a stable operating state, close the leak-proof ring water supply valve to ensure the sealing of the entire unit, prevent any external water or air leakage, and ultimately ensure that the unit is in a safe and normal operating state.

[0043] After adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art. Of course, any product implementing the present invention does not necessarily need to achieve all the advantages described below at the same time:

[0044] The phase-adjusting water pressure control system of the pumped storage unit of the present invention realizes the efficient operation of the unit under different working conditions by introducing a water pressure and air supply system, a water level control system, an exhaust system and a unit start-up control system. By injecting high-pressure gas into the runner chamber, the system can effectively reduce the power demand at the start of the unit and reduce the impact on the power grid; at the same time, by real-time monitoring and adjusting the water level in the runner chamber, the stable operation of the unit under the phase-adjusting condition is ensured, and the adjustment range of reactive power is greatly increased. In addition, the exhaust system can automatically discharge the compressed air in the runner chamber after the unit reaches the rated speed, so that the unit can quickly transition to the normal pumping operation state, thereby improving the overall operating efficiency. Combined with the unit status monitoring system, it can realize real-time adjustment of various key components, ensure the safe and stable operation of the unit under various working conditions, extend the service life of the equipment and improve energy efficiency.

[0045] The specific implementation modes of the present invention are further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The drawings described below are only some embodiments. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0047] Figure 1 This is the control logic diagram of the water pressure process;

[0048] Figure 2 This is the exhaust process control logic diagram.

[0049] It should be noted that these drawings and textual descriptions are not intended to limit the conceptual scope of the present invention in any way, but are intended to illustrate the concept of the present invention for those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0050] The present invention will now be described in further detail with reference to the accompanying drawings.

[0051] See also Figure 1-2 As shown, in this embodiment, a phase-adjusting water pressure control system of a pumped storage unit is provided, including a water pressure and air supply system, which is used to inject high-pressure gas into the runner chamber during the operation of the unit, reduce the water level in the runner chamber, make the runner rotate in the air, reduce the starting power of the unit, and minimize the active power of the unit under the phase-adjusting condition, and increase the reactive power adjustment range;

[0052] A water level control system, which monitors the water level in the tailwater pipe in real time and controls the water level in the runner chamber to maintain it at a predetermined position below the runner, so that the unit can operate safely under different operating conditions;

[0053] An exhaust system, the exhaust system comprising a runner chamber exhaust valve, which is used to gradually exhaust the compressed air in the runner chamber after the unit speed reaches the rated value, so that the pressure in the runner chamber is restored to a condition that allows the unit to pump water;

[0054] The unit start-up control system is responsible for automatically controlling the operation of the water pressure and air supply system and the exhaust system when the unit water pump is started, so that the unit can be safely started under low power state; the unit start-up control system can receive input signals from multiple sensors and control devices, and the input signals include: volute exhaust valve fully open, volute exhaust valve fully closed signal; bottom ring drainage return pipeline valve fully open, bottom ring drainage return pipeline valve fully closed signal; top cover drainage return pipeline valve fully open, top cover drainage return pipeline valve fully closed signal; volute circulation pipeline valve fully open, volute circulation pipeline valve fully closed signal; leak-proof ring water supply valve fully open, leak-proof ring water supply valve fully closed signal; phase-adjusting pressure air valve fully open, phase-adjusting pressure air valve fully closed signal; phase-adjusting air supply valve fully open, phase-adjusting air supply valve fully closed signal; tailwater pipe water level high, medium and low signals. The system's operating logic is automatically executed according to the status of the input signal, including: when the water level in the tailwater pipe is too high, the phase-adjusting air pressure valve and the air supply valve are automatically closed to reduce the air pressure; when the water level in the tailwater pipe is too low, the phase-adjusting air supply valve is automatically opened to replenish gas; when the unit is started, the water pressure and air supply system is controlled to gradually lower the water level, and the air pressure in the runner chamber is adjusted through the exhaust system.

[0055] The unit status monitoring system receives and processes input signals from multiple sensors, and automatically adjusts the working status of the compressed water supply system and the exhaust system based on the input signals. It is used to automatically generate control instructions according to the input signals, and the control instructions include: controlling the opening and closing of the volute exhaust valve; controlling the opening and closing of the bottom ring exhaust return pipeline valve; controlling the opening and closing of the top cover exhaust return pipeline valve; controlling the opening and closing of the volute circulation pipeline valve; controlling the opening and closing of the leak-proof ring water supply valve;

[0056] The phase-adjusting water pressure control system of the pumped storage unit of the present invention realizes the efficient operation of the unit under different working conditions by introducing a water pressure and air supply system, a water level control system, an exhaust system and a unit start-up control system. By injecting high-pressure gas into the runner chamber, the system can effectively reduce the power demand at the start of the unit and reduce the impact on the power grid; at the same time, by real-time monitoring and adjusting the water level in the runner chamber, the stable operation of the unit under the phase-adjusting condition is ensured, and the adjustment range of reactive power is greatly increased. In addition, the exhaust system can automatically discharge the compressed air in the runner chamber after the unit reaches the rated speed, so that the unit can quickly transition to the normal pumping operation state, thereby improving the overall operating efficiency. Combined with the unit status monitoring system, it can realize real-time adjustment of various key components, ensure the safe and stable operation of the unit under various working conditions, extend the service life of the equipment and improve energy efficiency.

[0057] In this embodiment, the pressurized water and air supply system includes a phase-adjusting pressure air valve for adjusting the air pressure during the phase-adjusting condition; a phase-adjusting air supply valve for replenishing the air pressure when needed, the exhaust system includes a volute exhaust valve for controlling the discharge of the gas in the runner chamber; a bottom ring exhaust return pipeline valve for exhausting and draining at the bottom ring; a top cover exhaust return pipeline valve for exhausting and draining at the top cover, the water level control system includes a tailwater pipe water level sensor for monitoring the water level in the tailwater pipe and providing high, medium and low water level status signals; a leak-proof ring water supply valve for controlling the water supply to the leak-proof ring to ensure the sealing of the unit, and the input signals of the unit status monitoring system include the status of the volute exhaust valve, the status of the bottom ring drain return pipeline valve, and the status of the tailwater pipe water level, and also includes a volute circulation pipeline valve for controlling the switching status of the circulation pipeline valve at the volute, thereby regulating the circulation flow in the system.

[0058] In the present embodiment, during the process of air pressure regulation, the pressurized water and air supply system will be based on fuzzy logic control, and the air pressure injection amount in the pressurized water and air supply system will be dynamically adjusted according to the real-time monitored water level, air pressure and speed data to stabilize the water level in the impeller chamber and avoid excessive or insufficient air pressure injection, thereby optimizing the performance of the unit during water pump operating start-up and phase adjustment operation.

[0059] In this embodiment, the steps of using fuzzy logic control to adjust the air pressure are:

[0060] Obtain the water level in the runner room, the air pressure in the water-pressure air supply system, and the speed of the unit and convert the collected continuous input data into fuzzy sets. Then, a fuzzy rule base is established based on historical data, where each rule contains conditions and corresponding control strategies.

[0061] The fuzzy inference engine infers the fuzzy results of water level, air pressure and speed based on real-time input data and fuzzy rule base to obtain fuzzy output. Subsequently, the fuzzy output is defuzzified to generate a specific air pressure regulation control quantity, which is used to indicate the increase or decrease of air pressure in the water pressure and air supply system;

[0062] According to the defuzzified control quantity, the air pressure injection amount of the pressurized water and air supply system is adjusted in real time. According to the adjusted water level, air pressure and speed changes, real-time monitoring and feedback are carried out to continuously optimize the air pressure injection strategy, so that the water level in the runner chamber is maintained within the predetermined range, and the energy consumption and performance under unit startup and phase adjustment conditions are optimized.

[0063] In this embodiment, the particle swarm optimization algorithm can also be used to establish and train an optimization model based on historical data according to the power grid demand, the current operating status of the unit, and the water pump load. The optimization model is used to dynamically optimize the output parameters of active and reactive power to ensure that the minimum value of active power is maintained while meeting the power grid demand, and to increase the adjustment range of reactive power. The optimization model is established by combining historical operating data and the real-time status of the unit, and the input parameters are continuously updated through the monitoring system to ensure that the optimization process is dynamic and real-time. This optimization based on actual operating data can adapt to different operating environments, and can make fast and accurate adjustments to ensure the best operating state, whether it is a water pump operating condition or a phase adjustment condition.

[0064] In this embodiment, the steps of dynamically optimizing the output parameters of active and reactive power using the particle swarm optimization algorithm are as follows:

[0065] Get the current operating status parameters of the unit, including the water pump load, grid demand, active power and reactive power initial values. Then, in the optimization model, initialize the particle swarm. The particles represent different output combinations of active power and reactive power. Each particle carries the output value of active power and reactive power. Then, set the optimization goal, that is, reduce the active power output value and expand the reactive power adjustment range while meeting the grid demand. Finally, construct the fitness function. To measure the performance of each power combination, where P target is the active power currently required by the power grid, P output is the current active power output value of the unit, Q output is the current reactive power output value of the unit, Q max is the maximum reactive power output value allowed by the unit, w1 and w2 are weight coefficients, which are used to balance the goals of minimizing active power and maximizing reactive power; the particle swarm optimization algorithm is used to dynamically optimize the active and reactive power output to ensure that the output of active power is reduced while meeting the needs of the power grid. This process continuously iterates and optimizes the power combination, so that the unit can always operate in the optimal state, reduce power loss, reduce energy consumption, improve the unit's operating efficiency, and thus reduce operating costs.

[0066] Assign an initial position and speed to each particle. The position represents the initial output value of active and reactive power, and the speed represents the moving speed of each particle in the power combination space. Then, randomly generate multiple particles, initialize all particles in the group, and calculate the fitness value of each particle. By expanding the adjustment range of reactive power, it can better adapt to the needs of the power grid, especially when the grid voltage fluctuates, it can quickly provide reactive power for adjustment and maintain the stability of the grid. This is crucial for the safe operation of the power system, especially when the grid load fluctuates greatly, it can significantly improve the stability of the grid.

[0067] According to the historical optimal position and global optimal position of each particle, the speed of each particle is updated, and its expression is: i (t+1)=w·v i (t)+c1·r1·(p best，i -x i (t))+c2·r2·(g best -x i (t)) where v i (t+1) is the velocity of the particle in the next iteration, w is the inertia weight, c1 and c2 are acceleration factors, r1 and r2 are random numbers, p best，i is the historical optimal position of particle i, g best is the global optimal position, x i (t) is the position of particle i at time t. Then, the updated velocity is used to adjust the position of the particle, that is, the active power and reactive power output values, which are expressed as: i (t+1)=x i (t)+v i (t+1), where x i (t+1) is the new power output combination of particle i at time t+1;

[0068] After adjusting the position of the particle, calculate the fitness value of each particle in the new position, compare the current fitness of each particle with the historical best fitness, and update the optimal position of the particle. At the same time, compare the fitness values ​​of all particles, update the global optimal position, and ensure that the global optimal active power and reactive power output combination is found. Then, determine whether the stop condition is met. The stop condition includes that the number of iterations reaches the preset value or the fitness change of the global optimal solution is less than the set threshold. If the stop condition is met, output the global optimal active power and reactive power combination as the power output parameter of the unit. Finally, according to the optimal power output combination obtained by the particle swarm optimization algorithm, adjust the active and reactive power output of the unit to ensure that the active power is maintained at a low value and maximize the reactive power adjustment range while meeting the grid demand. Finally, monitor the changes in grid demand in real time, and continuously adjust the active and reactive power output based on the particle swarm optimization algorithm. Through the particle swarm optimization algorithm, the system can achieve continuous optimization, and the algorithm will gradually approach the optimal solution over time. In the case of unit load changes or grid demand fluctuations, the system can adaptively adjust to ensure the optimal output combination of active and reactive power. This continuous self-optimization process enables the system to constantly adapt to environmental changes and ensures continued high efficiency in operation.

[0069] In this embodiment, the unit status monitoring system receives and processes input signals from multiple sensors, and automatically adjusts the working status of the pressurized water and air supply system and the exhaust system based on the input signals in the following steps:

[0070] First, by analyzing the collected signals, the current operating status of the unit is evaluated to determine whether the unit is in different operating modes such as water pump working condition, phase adjustment working condition or shutdown. Then, the preset operating parameters are compared with the analysis results and the preset operating parameters to determine whether the unit operating status needs to be adjusted. Then, according to the operating status of the unit and the monitoring results of the tailwater pipe water level, the operation of the pressurized water and air supply system is automatically adjusted. When the water level is lower than the preset value, the pressurized water and air supply system is controlled to open the air supply valve to increase the high-pressure gas injection to reduce the water volume in the runner chamber; when the water level is higher than the preset value, the air supply valve is closed to reduce the air pressure injection to ensure the water level stability. Then, based on the status of the volute exhaust valve and the bottom ring drainage return pipeline valve, the working status of the exhaust system is controlled. When the pressure in the runner chamber needs to be reduced, the volute exhaust valve and the bottom ring drainage return pipeline valve are opened to discharge excess gas; when the appropriate pressure is reached, the exhaust valve is closed to maintain the appropriate operating pressure.

[0071] A method for applying a phase-adjusting water pressure control system of a pumped storage unit includes a water pressure process control method, and the water pressure process control method includes the following steps:

[0072] First, close the volute exhaust valve to prevent air from overflowing from the volute part, ensuring that the system can effectively accumulate air pressure. Next, close the volute circulation pipeline valve to cut off the gas circulation path in the volute to ensure that the gas can act on the runner chamber. Then, close the bottom ring exhaust return pipeline valve to prevent gas or water leakage at the bottom ring to ensure that the water level in the runner chamber is reduced as expected. Finally, close the top cover exhaust return pipeline valve to cut off the exhaust and drainage pipes at the top cover to prevent unexpected water or gas flow. The water level and air pressure status of the tailwater pipe are monitored in real time through the unit status monitoring system, and the operating status of the pressurized water replenishment system and the exhaust system are dynamically adjusted according to actual needs. Through the precise control of air pressure and water level, the common problems of excessive water level or insufficient air pressure in traditional systems can be avoided, thereby ensuring that the unit always operates at the optimal power output state.

[0073] Open the electric valve for water supply to the stop ring and start injecting water into the stop ring to ensure the tightness of the system. This operation is to prevent gas from leaking from outside the unit during the subsequent injection process and ensure that the system can maintain effective gas pressure regulation;

[0074] Open the phase-adjusting air pressure valve and start injecting high-pressure gas into the runner chamber to gradually lower the water level in the runner chamber until the water level continues to drop to the predetermined target position. This is to reduce water resistance and power consumption during startup.

[0075] In order to lower the water level more quickly and steadily, open the phase-adjusting air supply valve and continuously inject additional gas. The operation of the air supply valve can improve the efficiency of gas injection and ensure that the water level can reach the required low level faster;

[0076] The system continuously monitors the water level changes in the tailwater pipe to ensure that the water level is adjusted within a reasonable range. If the tailwater pipe water level fails to drop to the set low level as expected, the system will proceed to the next step based on the feedback information;

[0077] If the water level does not reach the set low level, the system will start the timer. If the water level still does not reach the set low level within the specified time, the system will start the second water pressure operation and re-inject high-pressure gas.

[0078] When it is monitored that the water level in the tailwater pipe has reached the set low level, the phase-adjusting pressure valve and the phase-adjusting air supply valve are immediately closed to stop further gas injection. This prevents the water level from dropping excessively or the air pressure from being too high, ensuring that the system is in a stable state and ready to enter the next operation stage.

[0079] A phase-adjusting water pressure control system and a control method for a pumped storage unit, further comprising an exhaust process control method, the exhaust process control method comprising the following steps:

[0080] First, close the volute circulation pipeline valve to cut off the gas circulation path inside the volute to ensure that there is no gas backflow during the exhaust process. Next, close the phase-adjusting pressure valve to stop any additional gas injection to ensure that the air pressure in the runner chamber does not increase. Then, close the phase-adjusting air supply valve to prevent the system from continuing to inject gas during the exhaust stage, so that the exhaust process can proceed smoothly.

[0081] Open the volute exhaust valve to start discharging compressed gas from the runner chamber, gradually reducing the air pressure in the runner chamber. This operation is to ensure that the air can be discharged smoothly, so that the air pressure in the runner chamber returns to a range suitable for normal operation, and avoid affecting the stable operation of the unit due to excessive air pressure;

[0082] At the same time, open the top cover drainage return pipe valve to let the excess water at the top cover flow into the drainage pipe to prevent the water level in the runner chamber from being too high, which will affect the normal exhaust and operation. Next, open the bottom ring exhaust return pipe valve to continue to discharge the remaining water through the exhaust pipe of the bottom ring to further reduce the water level in the runner chamber and ensure that the water level in the system returns to normal.

[0083] The system sets a delay time to ensure that the exhaust operation is completed smoothly within the specified time. If the system fails to complete the exhaust within the preset time, it may be necessary to re-evaluate the exhaust strategy or check the equipment status to ensure smooth operation;

[0084] The system will detect whether the secondary splashing power has been reached, or monitor whether the water level in the tailwater pipe is too high. If the system detects that the unit has reached the set secondary splashing power, or the water level in the tailwater pipe is too high, the system will automatically terminate the exhaust process to prevent further exhaust operations from affecting the stability of the system.

[0085] When the exhaust and drainage process is completed, first close the top cover drainage return pipe valve to prevent water from continuing to flow into the drainage pipe, then close the bottom ring exhaust return pipe valve to ensure that the drainage and exhaust paths of the bottom ring are completely closed, thereby stabilizing the water level in the runner chamber;

[0086] Completely close the volute exhaust valve to end the entire exhaust operation, ensure that the air pressure in the runner chamber returns to normal levels, and the system smoothly enters the normal operation mode and prepares for the next step;

[0087] When the exhaust and drainage operations are completed and the system enters a stable operating state, close the leak-proof ring water supply valve to ensure the sealing of the entire unit, prevent any external water or air leakage, and ultimately ensure that the unit is in a safe and normal operating state.

[0088] The present invention is not limited to the above-mentioned embodiments. Anyone should be aware that any structural changes made under the enlightenment of the present invention, and any technical solutions that are the same or similar to the present invention, fall within the protection scope of the present invention. The technology, shape, and structural parts not described in detail in the present invention are all well-known technologies.

Claims

1. A phase-adjusting water pressure control system for a pumped storage unit, characterized in that: include: The pressurized water air supply system is used to inject high-pressure gas into the runner chamber during the operation of the unit to reduce the water level in the runner chamber, so that the runner rotates in the air, reducing the starting power of the unit, and minimizing the active power of the unit under phase adjustment conditions, thereby increasing the reactive power adjustment range; A water level control system, which monitors the water level in the tailwater pipe in real time and controls the water level in the runner chamber to maintain it at a predetermined position below the runner, so that the unit can operate safely under different operating conditions; An exhaust system, the exhaust system comprising a runner chamber exhaust valve, which is used to gradually exhaust the compressed air in the runner chamber after the unit speed reaches the rated value, so that the pressure in the runner chamber is restored to a condition that allows the unit to pump water; The unit start-up control system is responsible for automatically controlling the operation of the water pressure and air supply system and the exhaust system when the unit water pump is started, so that the unit can be started safely under low power conditions; The unit status monitoring system receives and processes input signals from a plurality of sensors, and automatically adjusts the working status of the pressurized water and air supply system and the exhaust system based on the input signals.

2. A pumped storage unit phase-adjusting water pressure control system and control method thereof according to claim 1, characterized in that: The pressurized water and air supply system includes a phase-adjusting pressure air valve for adjusting the air pressure during phase-adjusting conditions; a phase-adjusting air supply valve for replenishing the air pressure when needed; the exhaust system includes a volute exhaust valve for controlling the discharge of gas from the runner chamber; a bottom ring exhaust return pipeline valve for exhausting and draining at the bottom ring; a top cover exhaust return pipeline valve for exhausting and draining at the top cover; the water level control system includes a tailwater pipe water level sensor for monitoring the water level in the tailwater pipe and providing high, medium and low water level status signals; a leak-proof ring water supply valve for controlling the water supply of the leak-proof ring to ensure the sealing of the unit; the input signals of the unit status monitoring system include the status of the volute exhaust valve, the status of the bottom ring drain return pipeline valve, and the status of the tailwater pipe water level; and a volute circulation pipeline valve for controlling the switching status of the circulation pipeline valve at the volute, thereby regulating the circulation flow in the system.

3. A phase-adjusting water pressure control system and control method for a pumped storage unit according to claim 1, characterized in that: During the air pressure regulation process, the pressurized water and air supply system will be based on fuzzy logic control. According to the real-time monitored water level, air pressure and speed data, it will dynamically adjust the air pressure injection amount in the pressurized water and air supply system to stabilize the water level in the runner chamber and avoid excessive or insufficient air pressure injection, thereby optimizing the performance of the unit during water pump startup and phase adjustment operation.

4. A phase-adjusting water pressure control system and control method for a pumped storage unit according to claim 1, characterized in that: The steps for air pressure regulation using fuzzy logic control are: Obtain the water level in the runner room, the air pressure in the water-pressure air supply system, and the speed of the unit and convert the collected continuous input data into fuzzy sets. Then, a fuzzy rule base is established based on historical data, where each rule contains conditions and corresponding control strategies. The fuzzy inference engine infers the fuzzy results of water level, air pressure and speed based on real-time input data and fuzzy rule base to obtain fuzzy output. Subsequently, the fuzzy output is defuzzified to generate a specific air pressure regulation control quantity, which is used to indicate the increase or decrease of air pressure in the water pressure and air supply system; According to the defuzzified control quantity, the air pressure injection amount of the pressurized water and air supply system is adjusted in real time. According to the adjusted water level, air pressure and speed changes, real-time monitoring and feedback are carried out to continuously optimize the air pressure injection strategy, so that the water level in the runner chamber is maintained within the predetermined range, and the energy consumption and performance under unit startup and phase adjustment conditions are optimized.

5. A phase-adjusting water pressure control system and control method for a pumped storage unit according to claim 4, characterized in that: The particle swarm optimization algorithm can also be used to establish and train an optimization model based on historical data according to grid demand, the current operating status of the unit, and the water pump load. The optimization model can be used to dynamically optimize the output parameters of active and reactive power to ensure that the minimum active power value is maintained while meeting grid demand and increasing the adjustment range of reactive power.

6. A phase-adjusting water pressure control system and control method for a pumped storage unit according to claim 5, characterized in that: The steps of dynamically optimizing the output parameters of active and reactive power using the particle swarm optimization algorithm are as follows: Get the current operating status parameters of the unit, including the water pump load, grid demand, active power and reactive power initial values. Then, in the optimization model, initialize the particle swarm. The particles represent different output combinations of active power and reactive power. Each particle carries the output value of active power and reactive power. Then, set the optimization goal, that is, reduce the active power output value and expand the reactive power adjustment range while meeting the grid demand. Finally, construct the fitness function. To measure the performance of each power combination, where P target is the active power currently required by the power grid, P output is the current active power output value of the unit, Q output is the current reactive power output value of the unit, Q max is the maximum reactive power output value allowed by the unit, w1 and w2 are weight coefficients used to balance the goals of minimizing active power and maximizing reactive power; Assign an initial position and speed to each particle. The position represents the initial output value of active and reactive power, and the speed represents the moving speed of each particle in the power combination space. Then, randomly generate multiple particles, initialize all particles in the population, and calculate the fitness value of each particle. According to the historical optimal position and global optimal position of each particle, the speed of each particle is updated, and its expression is: i (t+1)=w·v i (t)+c1·r1·(p best,i -x i (t))+c2·r2·(g best -x i (t)) where v i (t+1) is the velocity of the particle in the next iteration, w is the inertia weight, c1 and c2 are acceleration factors, r1 and r2 are random numbers, p best，i is the historical optimal position of particle i, g best is the global optimal position, x i (t) is the position of particle i at time t. Then, the updated velocity is used to adjust the position of the particle, that is, the active power and reactive power output values, which are expressed as: i (t+1=x i (t)+v i (t+1), where x i (t+1) is the new power output combination of particle i at time t+1; After adjusting the position of the particles, the fitness value of each particle in the new position is calculated, the current fitness of each particle is compared with the historical best fitness, and the optimal position of the particle is updated. At the same time, the fitness values ​​of all particles are compared, and the global optimal position is updated to ensure that the global optimal active power and reactive power output combination is found. Then, it is determined whether the stopping condition is met. The stopping condition includes that the number of iterations reaches the preset value or the fitness change of the global optimal solution is less than the set threshold. If the stopping condition is met, the global optimal active power and reactive power combination is output as the power output parameter of the unit. Finally, according to the optimal power output combination obtained by the particle swarm optimization algorithm, the active and reactive power output of the unit is adjusted to ensure that the active power is maintained at a low value and the reactive power adjustment range is maximized while meeting the grid demand. Finally, the grid demand changes are monitored in real time, and the active and reactive power outputs are continuously adjusted based on the particle swarm optimization algorithm.

7. A phase-adjusting water pressure control system and control method for a pumped storage unit according to claim 6, characterized in that: The unit status monitoring system receives and processes input signals from multiple sensors, and automatically adjusts the working status of the pressurized water and air supply system and the exhaust system based on the input signals in the following steps: First, by analyzing the collected signals, the current operating status of the unit is evaluated to determine whether the unit is in different operating modes such as water pump working condition, phase adjustment working condition or shutdown. Then, the preset operating parameters are compared with the analysis results and the preset operating parameters to determine whether the operating status of the unit needs to be adjusted. Then, according to the operating status of the unit and the monitoring results of the tailwater pipe water level, the operation of the pressurized water and air supply system is automatically adjusted. When the water level is lower than the preset value, the pressurized water and air supply system is controlled to open the air supply valve to increase the high-pressure gas injection to reduce the water volume in the runner chamber; when the water level is higher than the preset value, the air supply valve is closed to reduce the air pressure injection to ensure the water level stability. Then, based on the status of the volute exhaust valve and the bottom ring drainage return pipeline valve, the working status of the exhaust system is controlled. When the pressure in the runner chamber needs to be reduced, the volute exhaust valve and the bottom ring drainage return pipeline valve are opened to discharge excess gas; when the appropriate pressure is reached, the exhaust valve is closed to maintain the operating pressure.

8. A method for applying the phase-adjusting water pressure control system of a pumped storage unit according to any one of claims 1 to 7, characterized in that: The invention comprises a water pressure process control method, and the water pressure process control method comprises the following steps: First, close the volute exhaust valve to prevent air from escaping from the volute part and ensure that the system can effectively accumulate air pressure. Next, close the volute circulation pipeline valve to cut off the gas circulation path in the volute. Then, close the bottom ring exhaust return pipeline valve to prevent gas or water leakage at the bottom ring. Finally, close the top cover exhaust return pipeline valve to cut off the exhaust and drainage pipelines at the top cover. Open the electric valve for water supply to the stop-leak ring and start injecting water into the stop-leak ring to ensure the tightness of the system. Open the phase-adjusting air pressure valve and start injecting high-pressure gas into the runner chamber, gradually lowering the water level in the runner chamber until the water level continues to drop to the predetermined target position, thereby reducing the power consumption during startup; In order to lower the water level more quickly and steadily, open the phase-adjusting air supply valve and continuously inject additional gas. The operation of the air supply valve can improve the efficiency of gas injection and ensure that the water level can reach the required low level more quickly; The system continuously monitors the water level changes in the tailwater pipe to ensure that the water level is adjusted within a reasonable range. If the tailwater pipe water level fails to drop to the set low level as expected, the system will proceed to the next step based on the feedback information; If the water level does not reach the set low level, the system will start the timer. If the water level still does not reach the set low level within the specified time, the system will start the second water pressure operation and re-inject high-pressure gas. When it is monitored that the water level in the tailwater pipe has reached the set low level, the phase-adjusting gas pressure valve and the phase-adjusting gas supply valve are immediately closed to stop further gas injection.

9. A phase-adjusting water pressure control system and control method for a pumped storage unit according to claim 8, characterized in that: The exhaust process control method also includes the following steps: First, close the volute circulation pipeline valve to cut off the gas circulation path inside the volute, then close the phase-adjusting pressure valve to stop any additional gas injection to ensure that the air pressure in the runner chamber does not increase, and then close the phase-adjusting air supply valve; Open the volute exhaust valve to start discharging compressed gas from the runner chamber, gradually reduce the air pressure in the runner chamber, and restore the air pressure in the runner chamber to a range suitable for normal operation; At the same time, open the top cover drainage return pipe valve to let the excess water at the top cover flow into the drainage pipe to prevent the water level in the runner chamber from being too high, which will affect the normal exhaust and operation. Next, open the bottom ring exhaust return pipe valve to continue to discharge the remaining water through the exhaust pipe of the bottom ring to further reduce the water level in the runner chamber. The system sets a delay time to ensure that the exhaust operation is completed smoothly within the specified time. If the system fails to complete the exhaust within the preset time, it is necessary to re-evaluate the exhaust strategy or check the equipment status; The system will detect whether the secondary splashing power has been reached, or monitor whether the water level in the tailwater pipe is too high. If the system detects that the unit has reached the set secondary splashing power, or the water level in the tailwater pipe is too high, the system will automatically terminate the exhaust process; When the exhaust and drainage process is completed, first close the top cover drainage return pipe valve to prevent water from continuing to flow into the drainage pipe, then close the bottom ring exhaust return pipe valve to ensure that the drainage and exhaust paths of the bottom ring are completely closed, thereby stabilizing the water level in the runner chamber; End the exhaust operation: completely close the volute exhaust valve, end the entire exhaust operation, and the system smoothly enters the normal operation mode, ready to perform the next operation; When the exhaust and drainage operations are completed and the system enters a stable operating state, close the leak-proof ring water supply valve.

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