Coordinated control system for variable speed pumped storage units

Abstract

The present application relates to a cooperative control system for a variable speed pumped storage unit; the system comprises: a monitoring module, a cooperative controller, an excitation module and a speed regulating module. When the variable speed pumped storage unit changes from a first operating condition to a second operating condition, the monitoring module, the cooperative controller, the excitation module and the speed regulating module cooperate and coordinate with each other, thereby achieving the adjustment of the guide vane opening of a water pump turbine in the variable speed pumped storage unit under different operating conditions, and the operation of the variable speed pumped storage unit with a target speed, a first power and a second power as operating targets; the use of this system can achieve power regulation, guide vane opening regulation and speed regulation of the variable speed pumped storage unit under different operating conditions, as well as a smooth conversion of the operating state during the transition process of different operating conditions, thereby reducing the impact on the variable speed pumped storage unit itself and the power grid, and improving the operating stability of the variable speed pumped storage unit.

Description

Technical Field

[0001] The present application relates to the field of pumped storage technology, and in particular to a coordinated control system for a variable speed pumped storage unit. Background Art

[0002] Variable speed pumped storage units have important operational advantages in the power grid. They can solve the frequency instability problem caused by the large-scale grid connection of renewable energy power generation, as well as the problem that fixed speed units (water pump working conditions) cannot adjust the input power. Through automatic frequency control, high-speed adjustment of the second power can be achieved, meeting the requirements of the power grid for continuous, accurate and rapid adjustment of the second power.

[0003] However, the AC excitation and speed regulator control in the variable speed pumped storage unit affect each other, which greatly increases the control coupling degree and causes the variable speed pumped storage unit to have low operating stability. Summary of the invention

[0004] Based on this, it is necessary to provide a coordinated control system for a variable speed pumped storage unit that can improve the operating stability of the variable speed pumped storage unit in response to the above technical problems.

[0005] In a first aspect, the present application provides a coordinated control system for a variable speed pumped storage unit, the system comprising a monitoring module, a coordinated controller, an excitation module and a speed regulating module, wherein the monitoring module is respectively connected to the coordinated controller, the excitation module and the speed regulating module, and the coordinated controller is respectively connected to the excitation module and the speed regulating module; wherein:

[0006] A monitoring module, for outputting control mode setting instructions corresponding to the second operating condition to the excitation module and the speed regulating module, outputting reactive power instructions corresponding to the second operating condition to the excitation module, and outputting active power instructions corresponding to the second operating condition to the cooperative controller when the variable speed pumped storage unit changes from the first operating condition to the second operating condition;

[0007] An excitation module, used for entering a power control mode or a speed control mode based on a control mode setting instruction, and instructing the variable speed pumped storage unit to operate with the first power included in the reactive power instruction as an operation target;

[0008] A speed control module is used to enter a power control mode, a speed control mode or an opening mode based on a control mode setting instruction;

[0009] The collaborative controller is used to optimize according to the unit operation characteristic curve, the second power included in the active power instruction and the current head or lift, obtain the target speed and target opening, and output the second power, target speed and target opening to the excitation module and the speed regulation module respectively according to the control mode of the excitation module and the speed regulation module, so as to adjust the guide vane opening of the water pump turbine in the variable speed pumped storage unit, and instruct the variable speed pumped storage unit to operate with the target speed and the second power as the operation target.

[0010] In one embodiment, when the first operating condition is a transfer shutdown condition and the second operating condition is a rotating standby condition, the speed regulating module enters a speed control mode based on a control mode setting instruction; the cooperative controller outputs a target opening and a target speed to the speed regulating module;

[0011] The monitoring module outputs a startup command to the speed regulating module to instruct the speed regulating module to start running; the speed regulating module adjusts the guide vane opening of the pump turbine according to the target opening, and the speed regulating module adjusts the speed of the variable speed pumped storage unit according to the target speed; the target speed is less than the synchronous speed of the variable speed pumped storage unit;

[0012] When the unit speed is greater than or equal to the target speed of the preset coefficient, the monitoring module outputs a start-up command to the excitation module to instruct the excitation module to start running. The excitation module establishes the stator voltage of the variable speed pumped storage unit according to the system voltage.

[0013] In one of the embodiments, the variable speed pumped storage unit further comprises a motor module and a switch module, the motor module is respectively connected to the excitation module and the pump turbine, and the motor module is connected to the power grid through the switch module;

[0014] When the first operating condition is the rotating standby operating condition and the second operating condition is the power generation operating condition, before the excitation module and the speed regulation module receive the control mode setting instruction, the monitoring module is also used to obtain the power information at both ends of the switch module, and when the power information meets the preset conditions, the monitoring module outputs a synchronization instruction to the switch module to instruct the switch module to close;

[0015] After entering the power generation condition, the excitation module enters the power control mode or the speed control mode based on the control mode setting instruction, and the speed regulation module enters the speed control mode or the power control mode based on the control mode setting instruction; the collaborative controller confirms the current control mode of the excitation module and the speed regulation module, and gradually loads the active power of the variable speed pumped storage unit to the target value.

[0016] In one of the embodiments, when the first operating condition is a power generation condition and the second operating condition is a transfer shutdown condition, when the guide vane opening of the pump turbine is the target opening and the variable speed pumped storage unit is operated at the target speed, the first power and the second power, the monitoring module outputs a disconnection instruction to the switch module to instruct the switch module to disconnect;

[0017] The collaborative controller outputs the control mode setting instruction to the speed regulating module again to instruct the speed regulating module to enter the speed control mode; the collaborative controller is also used to obtain the current water head of the variable speed pumped storage unit, the collaborative controller optimizes according to the unit operation characteristic curve and the water head, obtains the first speed and the first opening, the collaborative controller outputs the first speed and the first opening to the speed regulating module, the speed regulating module adjusts the guide vane opening of the pump turbine according to the first opening, and the speed regulating module adjusts the speed of the variable speed pumped storage unit according to the first speed; the collaborative controller outputs a zero power instruction to the excitation module;

[0018] The monitoring module outputs shutdown instructions to the speed regulating module and the excitation module respectively, so as to instruct the excitation module to de-excite, and instruct the speed regulating module to close the guide vanes of the pump turbine.

[0019] In one of the embodiments, the variable speed pumped storage unit further comprises a valve body assembly, which is arranged at the water inlet end of the pump turbine;

[0020] When the first operating condition is the power generation condition and the second operating condition is the power generation phase adjustment condition, when the guide vane opening of the pump-turbine is the target opening and the variable speed pumped storage unit is operated at the target speed, the first power and the second power, the monitoring module outputs an opening control instruction to the speed regulating module to instruct the speed regulating module to enter the opening control mode, the monitoring module outputs a speed control instruction to the excitation module to instruct the excitation module to enter the speed control mode, the collaborative controller outputs the phase adjustment speed to the excitation module to instruct the excitation module to instruct the variable speed pumped storage unit to operate according to the phase adjustment speed as the operating target, and the collaborative controller outputs a preset opening to the speed regulating module to instruct the speed regulating module to adjust the guide vane opening of the pump-turbine based on the preset opening;

[0021] When the speed of the variable speed pumped storage unit is greater than or equal to the phase adjustment speed, the monitoring module outputs a closing command to the speed regulating module to instruct the speed regulating module to close the guide vanes of the pump turbine, and the monitoring module controls the valve body assembly to close.

[0022] In one embodiment, the variable speed pumped storage unit further comprises a valve body assembly, a motor module and a switch module, the motor module is respectively connected to the excitation module and the water pump turbine, the motor module is connected to the power grid through the switch module, and the valve body assembly is arranged at the water inlet end of the water pump turbine;

[0023] When the first operating condition is the power generation phase adjustment condition and the second operating condition is the transfer shutdown condition, when the guide vane opening of the pump-turbine is the target opening and the variable speed pumped storage unit operates at the target speed, the first power and the second power, the monitoring module outputs a decoupling instruction to the switch module to instruct the switch module to disconnect, and the monitoring module outputs a shutdown instruction to the speed regulation module and the excitation module respectively to instruct the excitation module to de-excite and instruct the speed regulation module to close the guide vane of the pump-turbine, and the monitoring module controls the valve body assembly to close.

[0024] In one of the embodiments, the variable speed pumped storage unit further comprises a valve body assembly, which is arranged at the water inlet end of the pump turbine;

[0025] When the first operating condition is the power generation phase adjustment condition and the second operating condition is the power generation condition, before the excitation module and the speed regulation module receive the control mode setting instruction, the monitoring module confirms that the speed regulation module is in the opening control mode and confirms that the excitation module is in the speed control mode.

[0026] The collaborative controller outputs a preset opening to the speed regulating module to instruct the speed regulating module to adjust the guide vane opening of the pump turbine based on the preset opening; the collaborative controller outputs a phase-adjusting speed to the excitation module to instruct the excitation module to instruct the variable speed pumped storage unit to operate based on the phase-adjusting speed as the operating target;

[0027] When the speed of the variable speed pumped storage unit is greater than or equal to the phase adjustment speed, the monitoring module controls the valve body assembly to open; the collaborative controller outputs the target opening to the speed regulation module to instruct the speed regulation module to adjust the guide vane opening of the pump turbine based on the target opening.

[0028] In one of the embodiments, the variable speed pumped storage unit further comprises a valve body assembly, which is arranged at the water inlet end of the pump turbine;

[0029] When the first working condition is a transfer shutdown condition and the second working condition is a self-starting condition, the speed regulating module is also used to enter the opening control mode based on the control mode setting instruction, the excitation module enters the speed control mode based on the control mode setting instruction, and the monitoring module controls the valve body assembly to close;

[0030] The cooperative controller outputs the target speed to the excitation module, and the excitation module adjusts the speed of the variable speed pumped storage unit according to the target speed;

[0031] The cooperative controller outputs the target opening to the speed regulating module, and the speed regulating module adjusts the guide vane opening of the pump turbine according to the target opening;

[0032] When the speed of the variable speed pumped storage unit is greater than or equal to a preset multiple of the target speed, the monitoring module outputs a shutdown command to the excitation module to instruct the excitation module to de-excite.

[0033] In one of the embodiments, the variable speed pumped storage unit further comprises a motor module and a switch module, the motor module is respectively connected to the excitation module and the pump turbine, and the motor module is connected to the power grid through the switch module;

[0034] When the first operating condition is a self-starting condition and the second operating condition is a phase adjustment condition, wherein the phase adjustment condition includes a power generation phase adjustment condition and a pumping phase adjustment condition, the speed regulation module is also used to enter the opening control mode based on the control mode setting instruction; the monitoring module outputs a startup instruction to the excitation module to instruct the excitation module to start running and establish the stator voltage of the variable speed pumped storage unit; the monitoring module is also used to obtain the electric energy information at both ends of the switch module, and when the electric energy information meets the preset conditions, the monitoring module outputs a synchronization instruction to the switch module to instruct the switch module to close;

[0035] The excitation module enters the speed control mode based on the control mode setting instruction, and the speed regulation module is also used to enter the opening control mode based on the control mode setting instruction;

[0036] The cooperative controller outputs the target speed to the excitation module to instruct the excitation module to operate the variable speed pumped storage unit according to the target speed as the operating target. The cooperative controller outputs the target opening to the speed regulation module, and the speed regulation module adjusts the guide vane opening of the pump turbine based on the target opening.

[0037] In one of the embodiments, the variable speed pumped storage unit further comprises a valve body assembly, which is arranged at the water inlet end of the pump turbine;

[0038] When the first working condition is the pumping phase adjustment working condition and the second working condition is the pumping working condition, before the excitation module and the speed regulating module receive the control mode setting instruction, the monitoring module confirms that the speed regulating module is in the opening control mode and confirms that the excitation module is in the speed control mode.

[0039] The collaborative controller outputs a preset opening to the speed regulating module to instruct the speed regulating module to adjust the guide vane opening of the pump turbine based on the preset opening; the collaborative controller outputs a phase-adjusting speed to the excitation module to instruct the excitation module to instruct the variable speed pumped storage unit to operate based on the phase-adjusting speed as the operating target;

[0040] When the speed of the variable speed pumped storage unit is greater than or equal to the phase adjustment speed, the monitoring module controls the valve body assembly to open;

[0041] The collaborative controller performs optimization according to the minimum input power corresponding to the current head of the pump-turbine and the unit operation characteristic curve to obtain the second speed, the second opening and the minimum opening. The collaborative controller outputs the second speed to the excitation module, and the excitation module adjusts the speed of the variable speed pumped storage unit according to the second speed; the collaborative controller outputs the minimum opening to the speed regulating module, and the speed regulating module adjusts the guide vane opening of the pump-turbine according to the minimum opening;

[0042] When the time interval between the moment when the speed of the variable speed pumped storage unit reaches the second speed and the current moment is equal to the delay time, the collaborative controller outputs the second opening as the target opening to the speed regulation module.

[0043] In one embodiment, the variable speed pumped storage unit further includes a valve body assembly, a motor module and a switch module, the valve body assembly is arranged at the water inlet end of the water pump turbine; the motor module is respectively connected to the excitation module and the water pump turbine, and the motor module is connected to the power grid through the switch module;

[0044] When the first operating condition is the pumping operating condition and the second operating condition is the transfer shutdown operating condition, the monitoring module outputs the minimum input power corresponding to the current head of the pump-turbine as the second power to the collaborative controller, and when the guide vane opening of the pump-turbine is the target opening and the variable speed pumped storage unit operates at the target speed, the first power and the second power, the monitoring module outputs a speed control instruction to the excitation module to instruct the excitation module to enter the speed control mode, and the monitoring module outputs a shutdown instruction to the speed regulating module to instruct the speed regulating module to close the guide vanes of the pump-turbine;

[0045] When the active power and reactive power corresponding to the variable speed pumped storage unit are both less than the preset values, the monitoring module outputs a de-energizing command to the switch module to instruct the switch module to disconnect, the monitoring module outputs a shutdown command to the excitation module to instruct the excitation module to de-energize, and the monitoring module controls the valve body assembly to close.

[0046] In one of the embodiments, the variable speed pumped storage unit further comprises a valve body assembly, which is arranged at the water inlet end of the pump turbine;

[0047] When the first operating condition is the pumping operating condition and the second operating condition is the pumping phase adjustment operating condition, the monitoring module outputs the minimum input power corresponding to the current head of the pump-turbine as the second power to the cooperative controller, and when the guide vane opening of the pump-turbine is the target opening and the variable speed pumped storage unit operates at the target speed, the first power and the second power, the cooperative controller outputs a preset power instruction to the excitation module, and the excitation module adjusts the active power corresponding to the variable speed pumped storage unit to a preset size based on the preset power instruction; the monitoring module outputs a speed control instruction to the excitation module to instruct the excitation module to enter the speed control mode, and the monitoring module outputs a shutdown instruction to the speed regulation module to instruct the speed regulation module to close the guide vanes of the pump-turbine;

[0048] The cooperative controller outputs the phase-adjusting speed to the excitation module to instruct the excitation module to operate the variable speed pumped storage unit based on the phase-adjusting speed as the operating target. When the speed of the variable speed pumped storage unit is greater than or equal to the phase-adjusting speed, the monitoring module controls the valve body assembly to close.

[0049] The above-mentioned cooperative control system of the variable speed pumped storage unit is provided with a monitoring module, a cooperative controller, an excitation module and a speed regulating module in the cooperative control system. When the variable speed pumped storage unit changes from a first working condition to a second working condition, the monitoring module, the cooperative controller, the excitation module and the speed regulating module cooperate and coordinate with each other, thereby respectively adjusting the guide vane opening of the water pump turbine in the variable speed pumped storage unit under different working conditions, and instructing the operation of the variable speed pumped storage unit with the target speed, the first power and the second power as the operating targets. The application embodiment realizes power regulation, guide vane opening regulation and speed regulation of the variable speed pumped storage unit under different operating conditions, as well as smooth conversion of operating states during transitions between different operating conditions through mutual cooperation and coordination among the monitoring module, collaborative controller, excitation module and speed regulation module, thereby reducing the impact on the variable speed pumped storage unit itself and the power grid. Compared with the traditional method in which the control of the excitation module and the speed regulation module in the variable speed pumped storage unit affects each other, the operating stability of the variable speed pumped storage unit is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the drawings required for use in the embodiments of the present application or related technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0051] Figure 1 A structural block diagram of a coordinated control system of a variable speed pumped storage unit in one embodiment;

[0052] Figure 2 is a schematic diagram of an operating characteristic curve of a water turbine in an embodiment;

[0053] Figure 3 It is a schematic diagram of the operating characteristic curve of a water pump in one embodiment;

[0054] Figure 4 It is a schematic diagram of the structure of a variable speed pumped storage unit in one embodiment. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0056] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein are only for the purpose of describing the embodiments of this application and are not intended to limit this application.

[0057] It is understood that terms such as "first" and "second" in this application are only used to distinguish similar objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. The "connection" appearing in the embodiments of this application refers to various connection methods such as direct connection or indirect connection to achieve communication between devices, and the embodiments of this application do not make any limitation on this.

[0058] It will be understood that “at least one” means one or more, and “plurality” means two or more.

[0059] When used herein, the singular forms "a", "an", and "said / the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the relevant listed items.

[0060] With the development of AC and DC power grids, factors such as large-capacity transmission channel failures and power fluctuations caused by large-scale access to new energy sources have brought new challenges to power grid control methods, especially the lack of periodic spare capacity during the operation of the power grid, which poses a great threat to the safe and reliable operation of the power grid. Pumped storage power stations have the functions of peak-to-valley shifting, frequency and phase modulation, and emergency standby. They are an effective means to solve the peak-to-valley shifting and safe and reliable operation of the power grid, and play an important role in the stable operation of the power grid. At present, most of the units put into operation in pumped storage power stations are fixed-speed pumped storage units. In fixed-speed pumped storage units, the monitoring system only needs to control the speed governor to adjust the active power of the unit and control the excitation system to adjust the reactive power of the unit. The control of the speed governor and the excitation system is completely decoupled, and the control and adjustment of active / reactive power is simple and clear. However, fixed-speed pumped storage units can only adopt the control mode of "start-up-full load-stop" under the pump working condition, which cannot meet the requirements of the power grid for continuous, accurate and rapid adjustment of active power.

[0061] Variable speed pumped storage units came into being under the above circumstances. Variable speed pumped storage units can achieve high-speed regulation of active power through automatic frequency control, improve the frequency regulation accuracy of the power grid, and solve the problem of frequency instability caused by large-scale renewable energy power generation connected to the grid, as well as the problem that fixed speed pumped storage units cannot adjust input power under water pump conditions; in addition, variable speed pumped storage units also have a certain degree of asynchronous operation capability, and have better stable operation performance than conventional synchronous motors, which is conducive to improving the stability of the power system.

[0062] However, existing variable speed pumped storage units or variable speed water pumps often use AC excitation control to achieve rapid regulation of the output or input active power on the unit's stator side, and use speed governor control to achieve regulation of the input or output mechanical power on the unit's pump and turbine side. AC excitation control belongs to fast electromagnetic control, while speed governor control belongs to slow mechanical control. There are mutual influence and coordination issues between the active power controlled by AC excitation and the active power controlled by the speed governor, which directly affects the operating stability of the entire variable speed pumped storage unit. Furthermore, since the amplitude, phase and frequency of the rotor excitation current in the variable speed pumped storage unit are adjustable, its control dimension is greatly increased, and the decoupling of the unit speed and the grid frequency also leads to an increase in the unit's control target. The mutual influence of AC excitation and speed governor on active power regulation greatly increases the control coupling degree, and additional collaborative control devices or collaborative control modules are also added at the control object (or equipment) level. The above factors make the variable speed pumped storage unit The control difficulty and complexity are much higher than those of conventional fixed-speed pumped-storage units, and the existing variable-speed pumped-storage units generally only involve coordinated control of AC excitation and speed regulator under a single operating condition (steady-state operating condition) to achieve stable operation of the variable-speed pumped-storage unit, and do not involve multiple operating conditions. There is a problem of low operating stability of the variable-speed pumped-storage unit during the operating condition conversion process; it should be noted that the steady-state operating condition refers to the operating condition in which the variable-speed pumped-storage unit can maintain operation for a long time after the operating condition conversion process, and the operating conditions include transfer shutdown condition TS, rotating standby condition SR, power generation condition G, power generation phase adjustment condition GC, pumping phase adjustment condition PC, pumping condition P and self-starting condition.

[0063] The cooperative control system of the variable speed pumped storage unit provided in the embodiment of the present application is provided with a monitoring module, a cooperative controller, an excitation module and a speed regulating module in the cooperative control system. When the variable speed pumped storage unit changes from a first working condition to a second working condition, the monitoring module, the cooperative controller, the excitation module and the speed regulating module cooperate and coordinate with each other to realize the working condition conversion of the variable speed pumped storage unit. The cooperative controller performs optimization according to the unit operation characteristic curve and the second power included in the active power instruction to obtain the target speed and the target opening. The cooperative controller performs optimization according to the second power, the target speed and the target opening based on the second power, the target speed and the target opening. The coordinated excitation module and the speed regulation module respectively adjust the guide vane opening of the water pump turbine in the variable speed pumped storage unit, and instruct the operation of the variable speed pumped storage unit with the target speed and the second power as the operation target. The excitation module instructs the operation of the variable speed pumped storage unit with the first power included in the reactive instruction as the operation target, thereby controlling the electromagnetic active power and reactive power of the generator motor in the variable speed pumped storage unit (the active power and reactive power of the variable speed pumped storage unit), realizing rapid power regulation in the variable speed pumped storage unit while ensuring efficient and stable operation of the variable speed pumped storage unit.

[0064] In an exemplary embodiment, Figure 1 As shown, a coordinated control system 100 of a variable speed pumped storage unit is provided, the system 100 includes a monitoring module 110, a coordinated controller 120, an excitation module 130 and a speed regulating module 140, wherein the monitoring module 110 is respectively connected to the coordinated controller 120, the excitation module 130 and the speed regulating module 140, and the coordinated controller 120 is respectively connected to the excitation module 130 and the speed regulating module 140; wherein:

[0065] The monitoring module 110 is used to output control mode setting instructions corresponding to the second working condition to the excitation module 130 and the speed regulating module 140, output reactive power instructions corresponding to the second working condition to the excitation module 130, and output active power instructions corresponding to the second working condition to the cooperative controller 120 when the variable speed pumped storage unit changes from the first working condition to the second working condition;

[0066] The excitation module 130 is used to enter the power control mode or the speed control mode based on the control mode setting instruction, and to instruct the variable speed pumped storage unit to operate with the first power included in the reactive power instruction as the operation target;

[0067] The speed regulating module 140 is used to enter the power control mode, the speed control mode or the opening mode based on the control mode setting instruction;

[0068] The collaborative controller 120 is used to optimize according to the unit operation characteristic curve and the second power included in the active power instruction and the current head or lift, obtain the target speed and target opening, and output the second power, target speed and target opening to the excitation module 130 and the speed regulation module 140 respectively according to the control mode of the excitation module 130 and the speed regulation module 140, so as to adjust the guide vane opening of the pump turbine in the variable speed pumped storage unit, and instruct the variable speed pumped storage unit to operate with the target speed and the second power as the operating target.

[0069] Among them, the monitoring module 110 can be a monitoring system; the excitation module 130 can be an AC excitation; the speed regulation module 140 can be a speed regulator, which includes a PID (Proportional-Integral-Derivative) controller, which can be used to adjust the guide vane opening of the pump turbine and the speed of the variable speed pumped storage unit; the first operating condition and the second operating condition are different operating conditions, including the transfer shutdown condition TS, the rotating standby condition SR, the power generation condition G, the power generation phase adjustment condition GC, the pumping phase adjustment condition PC, the pumping condition P and the self-starting condition.

[0070] Exemplarily, the first power and the second power may be set according to actual conditions and are not limited in the embodiments of the present application.

[0071] Specifically, Figure 1 As shown, the monitoring module 110 outputs a reactive power instruction to the excitation module 130, and the excitation module 130 adjusts the reactive power corresponding to the variable speed pumped storage unit (the electromagnetic reactive power of the generator motor) by changing the magnitude of the rotor AC current; the cooperative controller 120 can store the unit operation characteristic curve. During the operating condition conversion process of the variable speed pumped storage unit, the cooperative controller 120 receives the active power instruction transmitted by the monitoring module 110, and optimizes based on the unit operation characteristic curve, the second power included in the active power instruction, and the current head or lift to obtain the target speed and target opening.

[0072] For example, the unit operation characteristic curve may include a turbine operating condition operation characteristic curve (such as Figure 2 as shown) and the pump operating characteristic curve (as shown Figure 3 As shown); the operating range and operating condition constraints are obtained by the pump turbine model test data of the main engine factory and the prototype model parameters are converted, that is, the unit operation characteristic curve can be obtained according to the existing method, which is not described in detail in the embodiment of the present application; it should be noted that whether it is the turbine operating condition operating characteristic curve (such as Figure 2 as shown) or the pump operating characteristic curve (as shown Figure 3As shown in the figure, the operating curves all reflect the information of four quantities (power or input, head or head, unit speed, guide vane opening); among them, power or input, head or head are inputs, unit speed and guide vane opening are outputs. When the power target (second power) and the current head or head are known, the collaborative controller can interpolate and calculate the optimal target speed (target speed) and the optimal target opening (target opening) by table lookup based on the above curves. It should be noted that the collaborative controller can be connected to the head sensor in the variable speed pumped storage unit to obtain the current head or head.

[0073] When the excitation module 130 is in the power control mode and the speed regulating module 140 is in the speed control mode, the cooperative controller 120 outputs an active power instruction to the excitation module 130, and outputs a target speed and a target opening to the speed regulating module 140. The excitation module 130 takes the second power as the operating target, and quickly adjusts the active power (electromagnetic active power of the generator motor) corresponding to the variable speed pumped storage unit by changing the phase and frequency of the rotor AC current. The speed regulating module 140 adjusts the guide vane opening of the pump turbine in the variable speed pumped storage unit and the speed of the variable speed pumped storage unit according to the target speed (operating target) and the target opening. Among them, the speed of the variable speed pumped storage unit refers to the speed of the rotating part in the variable speed pumped storage unit, and the rotating part includes the motor rotor and the runner of the pump turbine. The rotating part may also include other components, which are not described in detail in the embodiments of the present application.

[0074] When the excitation module 130 is in the speed control mode and the speed regulation module 140 is in the power control mode, the cooperative controller 120 outputs the target speed to the excitation module 130, and outputs the active power instruction and the target opening to the speed regulation module 140. The speed regulation module 140 takes the second power as the operating target and adjusts the guide vane opening of the pump turbine in the variable speed pumped-storage unit according to the target opening. The excitation module 130 adjusts the speed of the variable speed pumped-storage unit according to the target speed (operating target).

[0075] The above-mentioned cooperative control system of the variable speed pumped-storage unit is configured with a monitoring module, a cooperative controller, an excitation module and a speed regulating module. When the variable speed pumped-storage unit changes from a first operating condition to a second operating condition, the monitoring module, the cooperative controller, the excitation module and the speed regulating module cooperate and coordinate with each other, thereby realizing the adjustment of the guide vane opening of the water pump turbine in the variable speed pumped-storage unit under different operating conditions, and the operation of the variable speed pumped-storage unit with the target speed, the first power and the second power as the operating target, thereby controlling the electromagnetic active power and reactive power of the generator motor, realizing the power regulation and speed regulation of the variable speed pumped-storage unit under different operating conditions, and the smooth conversion of the operating state during the transition process of different operating conditions, thereby improving the operating stability of the variable speed pumped-storage unit.

[0076] In one embodiment, when the first operating condition is a transfer shutdown condition and the second operating condition is a rotating standby condition, the speed regulating module enters a speed control mode based on a control mode setting instruction; the cooperative controller outputs a target opening and a target speed to the speed regulating module;

[0077] The monitoring module outputs a startup command to the speed regulating module to instruct the speed regulating module to start running; the speed regulating module adjusts the guide vane opening of the pump turbine according to the target opening, and the speed regulating module adjusts the speed of the variable speed pumped storage unit according to the target speed; the target speed is less than the synchronous speed of the variable speed pumped storage unit;

[0078] When the unit speed is greater than or equal to the target speed of the preset coefficient, the monitoring module outputs a start-up command to the excitation module to instruct the excitation module to start running. The excitation module establishes the stator voltage of the variable speed pumped storage unit according to the system voltage.

[0079] Among them, the preset coefficient can be set according to actual conditions and is not limited in the embodiments of the present application; the monitoring module can also be used to output working mode setting instructions to instruct the collaborative controller, excitation module and speed regulation module to enter the corresponding working mode; the monitoring module can also be used to output control mode setting instructions to the collaborative controller to instruct the collaborative controller to enter the corresponding control mode.

[0080] Specifically, when the variable speed pumped storage unit changes from the transit shutdown condition to the rotating standby condition, the monitoring module outputs the working mode setting instruction to the collaborative controller, the excitation module and the speed regulation module, instructing the collaborative controller, the excitation module and the speed regulation module to enter the power generation mode, and the monitoring module outputs the control mode setting instruction to the collaborative controller, instructing the collaborative controller to enter the speed control mode. Among them, because the second condition is the rotating standby condition, the active power instruction corresponding to the second condition is a zero active power instruction, that is, the second power contained in the active power instruction is zero. At this time, the collaborative controller can optimize according to the current water head and the unit operation characteristic curve to obtain the starting speed (target speed) and no-load opening (target opening), and the collaborative controller outputs a zero active power instruction to the excitation module.

[0081] It should be noted that the collaborative controller, excitation module and speed regulation module can all enter corresponding working modes and corresponding control modes, and the two modes can exist at the same time. The working mode can be used to indicate the subsequent working conditions, and the control mode can include a speed control mode, which performs closed-loop control with speed as the target; a power control mode, which performs closed-loop control with power as the target; and an opening control mode, which performs closed-loop control with guide vane opening as the target.

[0082] The monitoring module outputs a startup command and a mode control command to the speed regulating module to instruct the speed regulating module to start running and enter the speed control mode. The collaborative controller outputs the starting speed and the no-load opening to the speed regulating module. The speed regulating module adjusts the guide vane opening of the pump turbine according to the no-load opening, and adjusts the speed of the variable speed pumped storage unit to the starting speed. When the speed is greater than or equal to the target speed of the preset coefficient, the monitoring module outputs a startup command and a preset mode control command to the excitation module. The excitation module starts running and automatically controls the stator voltage (which changes with the system bus voltage) so that the magnitude, frequency and phase of the stator voltage are exactly the same as the bus voltage (system voltage).

[0083] Exemplarily, the starting speed needs to be lower than the synchronous speed of the variable speed pumped storage unit to prevent the variable speed pumped storage unit from entering the "S" characteristic unstable zone when running at no-load, causing the variable speed pumped storage unit to have poor operating stability and difficulty in connecting to the grid; and the target speed is related to the current water head H. The lower the current water head H, the lower the starting speed requirement. The lower speed limit corresponding to the current operating condition can be used as the starting speed.

[0084] Among them, the synchronous speed is the speed corresponding to the slip rate of zero at the rated grid frequency; the speed of the variable speed pumped storage unit can be obtained according to an external speed measurement device, which is not repeated in the embodiment of the present application.

[0085] In the embodiment of the present application, when the variable speed pumped storage unit is changed from the transit shutdown condition to the rotating standby condition, the monitoring module, the collaborative controller, the excitation module and the speed regulating module cooperate and coordinate with each other, so that the speed regulating module adjusts the guide vane opening of the pump turbine according to the target opening, the speed regulating module adjusts the speed of the variable speed pumped storage unit according to the target speed, and the excitation module automatically controls the stator voltage (which changes with the system bus voltage), so as to realize the smooth conversion of the variable speed pumped storage unit from the transit shutdown condition to the rotating standby condition, thereby improving the operating stability of the variable speed pumped storage unit.

[0086] In one of the embodiments, the variable speed pumped storage unit further comprises a motor module and a switch module, the motor module is respectively connected to the excitation module and the pump turbine, and the motor module is connected to the power grid through the switch module;

[0087] When the first operating condition is the rotating standby operating condition and the second operating condition is the power generation condition, before the excitation module and the speed regulation module receive the control mode setting instruction, the monitoring module is also used to obtain the power information at both ends of the switch module, and when the power information meets the preset conditions, the monitoring module outputs a synchronization instruction to the switch module to instruct the switch module to close.

[0088] After entering the power generation condition, the excitation module enters the power control mode or the speed control mode based on the control mode setting instruction, and the speed regulation module enters the speed control mode or the power control mode based on the control mode setting instruction; the collaborative controller confirms the current control mode of the excitation module and the speed regulation module, and gradually loads the active power of the variable speed pumped storage unit to the target value.

[0089] Among them, Figure 4 As shown, the motor module can be a variable speed motor; the switch module can be a GCB (Generator Circuit-Breaker); the preset conditions can be set according to actual conditions and are not limited in the embodiments of the present application; a synchronization device can be provided in the monitoring module, and the synchronization device can obtain the power information (voltage, current) at both ends of the switch module, and output a synchronization instruction when the power information meets the preset conditions.

[0090] Specifically, Figure 4 As shown, when the variable speed pumped storage unit changes from the rotating standby condition to the power generation condition, the monitoring module (synchronization device) can obtain the electric energy information at both ends of the switch module through the excitation module, and when the electric energy information meets the preset conditions, it outputs a synchronization instruction to the switch module to instruct the switch module to close, and the variable speed pumped storage unit is connected to the grid (grid-connected).

[0091] After the variable speed pumped storage unit is connected to the grid, if the monitoring module outputs control mode setting instructions to the cooperative controller, excitation module and speed regulation module respectively, to instruct the cooperative controller to enter the power priority mode, the excitation module to enter the power control mode, and the speed regulation module to enter the speed control mode, then the monitoring module sends the active power given value P to the cooperative controller through the active power instruction. ref (Second power), after confirming that the control modes of the speed regulation module and the excitation module are correct, the cooperative controller outputs the active power instruction to the excitation module, and controls the excitation module to adjust the active power of the variable speed pumped storage unit with a preset slope, and the cooperative controller sends the optimal speed instruction (including the target speed) and the optimal opening instruction (including the target opening) output by the optimization to the speed regulation module, the speed regulation module adjusts the guide vane opening of the pump turbine according to the target opening, and adjusts the speed of the variable speed pumped storage unit according to the target speed, and the excitation module adjusts the power of the variable speed pumped storage unit with the first power and the second power as the operating targets; wherein, the preset slope can be set according to actual conditions and is not limited in the embodiments of the present application.

[0092] After the variable speed pumped storage unit is connected to the grid, if the monitoring module outputs control mode setting instructions to the cooperative controller, excitation module and speed regulation module respectively, to instruct the cooperative controller to enter the speed priority mode, the excitation module to enter the speed control mode, and the speed regulation module to enter the power control mode, then the monitoring module sends the active power given value P to the cooperative controller through the active power instruction. ref (Second power), after confirming that the control modes of the speed control module and the excitation module are correct, the cooperative controller outputs the active power instruction to the speed control module, and controls the speed control module to adjust the active power of the variable speed pumped storage unit with a preset slope, and the cooperative controller sends the optimal opening instruction (including the target opening) output by optimization to the speed control module, and the speed control module adjusts the guide vane opening of the pump turbine according to the target opening; the cooperative controller outputs the reactive power and the optimal speed instruction (including the target speed) output by optimization to the excitation module, and the excitation module adjusts the speed of the variable speed pumped storage unit according to the target speed, and the excitation module adjusts the power of the variable speed pumped storage unit with the first power as the operating target.

[0093] To facilitate understanding by those skilled in the art, the following is an explanation of the adjustment (loading or unloading) of the active power of the variable-speed pumped-storage unit with a preset slope in combination with a specific example. Assuming that the second power issued by the monitoring module changes from 100MW to 200MW, the collaborative controller will not change the active power from 100MW to 200MW in a step-by-step manner after receiving the new active power instruction of 200MW. The collaborative controller will gradually adjust the operating target from 100MW to 200MW according to the preset slope (for example, 5MW / s), and the corresponding target speed and target opening will also gradually change from the original corresponding values ​​of 100MW to the target speed and target opening corresponding to 200MW.

[0094] In the embodiment of the present application, when the variable speed pumped storage unit is converted from a rotating standby condition to a power generation condition, the monitoring module, the collaborative controller, the excitation module and the speed regulating module cooperate and coordinate with each other. When the electric energy information meets the preset conditions, the monitoring module controls the switch module to close, and the variable speed pumped storage unit is connected to the power grid. The monitoring module instructs the excitation module and the speed regulating module through the collaborative controller to respectively adjust the guide vane opening of the pump turbine in the variable speed pumped storage unit, and to instruct the operation of the variable speed pumped storage unit with the target speed and the second power as the operating targets. The monitoring module instructs the excitation module to instruct the operation of the variable speed pumped storage unit with the first power as the operating target, thereby achieving a smooth conversion of the variable speed pumped storage unit from a rotating standby condition to a power generation condition, reducing the impact on the variable speed pumped storage unit itself and the power grid, and improving the operating stability of the variable speed pumped storage unit.

[0095] In one of the embodiments, when the first operating condition is a power generation condition and the second operating condition is a transfer shutdown condition, when the guide vane opening of the pump turbine is the target opening and the variable speed pumped storage unit is operated at the target speed, the first power and the second power, the monitoring module outputs a disconnection instruction to the switch module to instruct the switch module to disconnect;

[0096] The collaborative controller outputs the control mode setting instruction to the speed regulating module again to instruct the speed regulating module to enter the speed control mode; the collaborative controller is also used to obtain the current water head of the variable speed pumped storage unit, the collaborative controller optimizes according to the unit operation characteristic curve and the water head, obtains the first speed and the first opening, the collaborative controller outputs the first speed and the first opening to the speed regulating module, the speed regulating module adjusts the guide vane opening of the pump turbine according to the first opening, and the speed regulating module adjusts the speed of the variable speed pumped storage unit according to the first speed; the collaborative controller outputs a zero power instruction to the excitation module;

[0097] The monitoring module outputs shutdown instructions to the speed regulating module and the excitation module respectively, so as to instruct the excitation module to de-excite, and instruct the speed regulating module to close the guide vanes of the pump turbine.

[0098] Among them, the preset power instruction can be set according to actual conditions. In the embodiment of the present application, the preset power instruction is set as a zero active power instruction as an example for explanation.

[0099] Specifically, when the variable speed pumped storage unit is changed from the power generation condition to the transfer shutdown condition, because the second condition is the transfer shutdown condition, the reactive power instruction corresponding to the second condition is a zero reactive power instruction, that is, the first power contained in the reactive power instruction is zero, and the active power instruction corresponding to the second condition is a zero active power instruction, that is, the second power contained in the active power instruction is zero. The cooperative controller outputs the reactive power instruction to the excitation module, and controls the excitation module to reduce the reactive power of the variable speed pumped storage unit to zero according to a preset slope. The cooperative controller controls the excitation module according to the control mode of the excitation module and the speed regulation module, when the excitation module is in the power control mode. When the excitation module is in the speed control mode and the speed regulation module is in the speed control mode, the cooperative controller outputs the active power instruction to the excitation module, and outputs the target speed and the target opening to the speed regulation module; when the excitation module is in the speed control mode and the speed regulation module is in the power control mode, the cooperative controller outputs the target speed to the excitation module, and outputs the active power instruction and the target opening to the speed regulation module, and the cooperative controller reduces the second power of the variable speed pumped storage unit to zero according to a preset slope, and the target speed and the target opening correspond to the second power, so as to synchronously adjust the guide vane opening of the water pump turbine in the variable speed pumped storage unit and the speed of the variable speed pumped storage unit.

[0100] like Figure 4As shown, when the active power and reactive power of the variable speed pumped storage unit are reduced to zero, the monitoring module outputs a disconnection instruction to the switch module to instruct the switch module to disconnect, and the variable speed pumped storage unit is disconnected from the grid. The monitoring module outputs a control mode setting instruction to the speed regulating module to instruct the speed regulating module to enter the speed control mode. The collaborative controller obtains the current water head through the water head sensor, and optimizes according to the unit operation characteristic curve and the water head to obtain the corresponding first speed and first opening. The collaborative controller outputs the first speed and the first opening to the speed regulating module, and the speed regulating module adjusts the variable speed pumped storage unit accordingly. The cooperative controller outputs a zero-power command to the excitation module according to the guide vane opening of the pump-turbine in the variable-speed pumped-storage unit and the speed of the variable-speed pumped-storage unit. When the speed regulation module adjusts the guide vane opening of the pump-turbine in the variable-speed pumped-storage unit to the first opening and adjusts the speed of the variable-speed pumped-storage unit to the first speed, the monitoring module outputs a shutdown command to the speed regulation module and the excitation module respectively to instruct the excitation module to de-excite and instruct the speed regulation module to close the guide vanes of the pump-turbine. After the guide vanes are closed, the monitoring module can also be used to reset the working modes of the cooperative controller, the excitation module and the speed regulation module.

[0101] In the embodiment of the present application, when the variable speed pumped storage unit is changed from the power generation condition to the transfer shutdown condition, the monitoring module, the collaborative controller, the excitation module and the speed regulating module cooperate and coordinate with each other. When the guide vane opening of the pump turbine is the target opening and the variable speed pumped storage unit is operating at the target speed, the first power and the second power, the monitoring module instructs the switch module to disconnect, and instructs the excitation module and the speed regulating module to enter the corresponding control mode respectively. The collaborative controller obtains the first speed and the first opening according to the current water head, and the monitoring module outputs a zero power instruction to the excitation module to adjust the guide vane opening of the pump turbine in the variable speed pumped storage unit, and instruct the variable speed pumped storage unit to operate with the first speed and the preset power as the operating target, thereby reducing the impact on the variable speed pumped storage unit itself and the power grid, realizing the smooth conversion of the variable speed pumped storage unit from the power generation condition to the transfer shutdown condition, and improving the operating stability of the variable speed pumped storage unit.

[0102] In one of the embodiments, the variable speed pumped storage unit further comprises a valve body assembly, which is arranged at the water inlet end of the pump turbine;

[0103] When the first operating condition is the power generation condition and the second operating condition is the power generation phase adjustment condition, when the guide vane opening of the pump-turbine is the target opening and the variable speed pumped storage unit is operated at the target speed, the first power and the second power, the monitoring module outputs an opening control instruction to the speed regulating module to instruct the speed regulating module to enter the opening control mode, the monitoring module outputs a speed control instruction to the excitation module to instruct the excitation module to enter the speed control mode, the collaborative controller outputs the phase adjustment speed to the excitation module to instruct the excitation module to instruct the variable speed pumped storage unit to operate according to the phase adjustment speed as the operating target, and the collaborative controller outputs a preset opening to the speed regulating module to instruct the speed regulating module to adjust the guide vane opening of the pump-turbine based on the preset opening;

[0104] When the speed of the variable speed pumped storage unit is greater than or equal to the phase adjustment speed, the monitoring module outputs a closing command to the speed regulating module to instruct the speed regulating module to close the guide vanes of the pump turbine, and the monitoring module controls the valve body assembly to close.

[0105] Among them, the type of valve body assembly can be set according to actual conditions. In the embodiment of the present application, the valve body assembly is taken as an example of a ball valve; the phase adjustment speed can be set according to actual conditions. It should be noted that the corresponding phase adjustment speeds under different working conditions can be the same size or different sizes, which is not limited in the embodiment of the present application; the preset opening can be set according to actual conditions. It should be noted that the corresponding preset openings under different working conditions can be the same size or different sizes, which is not limited in the embodiment of the present application.

[0106] Specifically, when the variable speed pumped storage unit is changed from the power generation condition to the power generation phase adjustment condition, wherein, because the second condition is the power generation phase adjustment condition, the active power instruction corresponding to the second condition is a zero active power instruction, that is, the second power contained in the active power instruction is zero. At this time, the collaborative controller can control the excitation module or the speed regulation module to adjust the active power of the variable speed pumped storage unit with a preset slope. The collaborative controller sends the optimal speed instruction (including the target speed) and the optimal opening instruction (target opening) output by the optimized search based on the changing active power and the unit operation characteristic curve to the excitation module or the speed regulation module, so as to adjust the guide vane opening of the pump turbine according to the target opening, and adjust the speed of the variable speed pumped storage unit according to the target speed; wherein, the preset slope can be set according to actual conditions and is not limited in the embodiments of the present application.

[0107] It should be noted that, according to the control modes of the excitation module and the speed regulation module, when the excitation module is in the power control mode and the speed regulation module is in the speed control mode, the collaborative controller outputs the active power command to the excitation module, and outputs the target speed and the target opening to the speed regulation module; when the excitation module is in the speed control mode and the speed regulation module is in the power control mode, the collaborative controller outputs the target speed to the excitation module, and outputs the active power command and the target opening to the speed regulation module, and the collaborative controller reduces the second power of the variable speed pumped-storage unit to zero according to a preset slope, and the target speed and the target opening correspond to the second power, so as to synchronously adjust the guide vane opening of the pump turbine in the variable speed pumped-storage unit, and the speed of the variable speed pumped-storage unit.

[0108] When the active power (active load) of the variable speed pumped storage unit drops to zero, the monitoring module outputs the working mode setting command value to the cooperative controller to instruct the cooperative controller to enter the speed priority mode first; the monitoring module outputs the opening control command to the speed regulating module to instruct the speed regulating module to enter the opening control mode, the monitoring module outputs the speed control command to the excitation module to instruct the excitation module to enter the speed control mode, and the monitoring module outputs the working mode setting command value to the cooperative controller again to instruct the cooperative controller to switch to the power generation phase adjustment mode, wherein the cooperative controller is first set to the speed priority mode in order to set the excitation module to the speed control mode in conjunction with the speed control mode, because the cooperative controller will detect the control modes of the excitation module and the speed regulating module. If it does not conform to the current control mode of the cooperative controller, the cooperative controller will consider that the control mode of the excitation module or the speed regulating module is abnormal and output an alarm message; the cooperative controller is then set to the power generation phase adjustment mode in order to indicate that the cooperative controller will subsequently enter the power generation phase adjustment condition, so that the cooperative controller can prepare the instructions required for phase adjustment in advance (for example: phase adjustment speed); at this time, the speed of the variable speed pumped storage unit is maintained at the target speed.

[0109] The cooperative controller outputs the phase-adjusting speed to the excitation module to instruct the excitation module to instruct the variable speed pumped storage unit to operate according to the phase-adjusting speed as the operating target. The cooperative controller outputs a preset opening (zero target opening or a small target opening) to the speed regulating module to instruct the speed regulating module to adjust the guide vane opening of the pump-turbine based on the preset opening. When the speed of the variable speed pumped storage unit is maintained at (greater than or equal to) the phase-adjusting speed, the monitoring module outputs a working mode setting instruction and a closing instruction to the speed regulating module respectively to instruct the speed regulating module to enter the power generation phase-adjusting mode, and to instruct the speed regulating module to close the guide vanes of the pump-turbine. After the guide vanes are closed, the monitoring module controls the valve body assembly to close, and performs air-filled water pressurization to enable the variable speed pumped storage unit to enter the power generation phase-adjusting condition.

[0110] Exemplarily, the small target opening can be set according to actual conditions. In the embodiment of the present application, the small target opening can be adjusted in linkage with the phase modulation speed. For example, the higher the phase modulation speed, the more adaptively the small target opening can be, and vice versa.

[0111] Among them, because the variable speed pumped storage unit needs to close the guide vane when entering the power generation phase adjustment condition, if it is an ordinary fixed speed pumped storage unit, the guide vane can be directly closed due to the internal configuration of the synchronous motor, but the guide vane cannot be directly closed for the variable speed pumped storage unit (closing the guide vane will cause the mechanical motive force to disappear, and if the excitation module does not control the speed, it will cause the speed to drop), so the speed control module needs to be adjusted to the opening control mode and the excitation module needs to be adjusted to the speed control mode before the guide vane can be closed, so that the speed of the variable speed pumped storage unit can be maintained unchanged during and after closing the guide vane.

[0112] In the embodiment of the present application, when the variable speed pumped storage unit is changed from the power generation condition to the power generation phase adjustment condition, through the cooperation and coordination of the monitoring module, the collaborative controller, the excitation module and the speed regulation module, when the guide vane opening of the pump-turbine is the target opening, and the variable speed pumped storage unit is operated at the target speed, the first power and the second power, the monitoring module instructs the excitation module and the speed regulation module to enter the corresponding control mode respectively, the collaborative controller outputs the phase adjustment speed to the excitation module, and outputs the preset opening to the speed regulation module, so as to adjust the guide vane opening of the pump-turbine in the variable speed pumped storage unit, and instruct the variable speed pumped storage unit to operate with the phase adjustment speed as the operation target, when the speed of the variable speed pumped storage unit is greater than or equal to the phase adjustment speed, the monitoring module instructs the speed regulation module to close the guide vane of the pump-turbine, and the valve body assembly is closed, so as to realize the smooth conversion of the variable speed pumped storage unit from the power generation condition to the power generation phase adjustment condition, and improve the operation stability of the variable speed pumped storage unit.

[0113] In one embodiment, the variable speed pumped storage unit further comprises a valve body assembly, a motor module and a switch module, the motor module is respectively connected to the excitation module and the water pump turbine, the motor module is connected to the power grid through the switch module, and the valve body assembly is arranged at the water inlet end of the water pump turbine;

[0114] When the first operating condition is the power generation phase adjustment condition and the second operating condition is the transfer shutdown condition, when the guide vane opening of the pump-turbine is the target opening and the variable speed pumped storage unit operates at the target speed, the first power and the second power, the monitoring module outputs a decoupling instruction to the switch module to instruct the switch module to disconnect, and the monitoring module outputs a shutdown instruction to the speed regulation module and the excitation module respectively to instruct the excitation module to de-excite and instruct the speed regulation module to close the guide vane of the pump-turbine, and the monitoring module controls the valve body assembly to close.

[0115] Specifically, Figure 4 As shown, when the variable speed pumped storage unit changes from the power generation phase adjustment condition to the transfer shutdown condition, wherein, because the second condition is the transfer shutdown condition, the reactive power instruction corresponding to the second condition is a zero reactive power instruction, that is, the first power contained in the reactive power instruction is zero. At this time, the monitoring module can control the excitation module to adjust the reactive power of the variable speed pumped storage unit with a preset slope, and the collaborative controller sends the optimal speed instruction (including the target speed) and the optimal opening instruction (target opening) output by the optimization to the excitation module or the speed regulation module based on the second power in the active power instruction and the unit operation characteristic curve, so as to adjust the guide vane opening of the pump turbine according to the target opening (zero opening target), and adjust the speed of the variable speed pumped storage unit according to the target speed; wherein, the preset slope can be set according to the actual situation, and is not limited in the embodiment of the present application; the zero opening target is an opening of zero.

[0116] It should be noted that, according to the control modes of the excitation module and the speed regulation module, when the excitation module is in the power control mode and the speed regulation module is in the speed control mode, the collaborative controller outputs the active power command to the excitation module, and outputs the target speed and the target opening to the speed regulation module; when the excitation module is in the speed control mode and the speed regulation module is in the power control mode, the collaborative controller outputs the target speed to the excitation module, and outputs the active power command and the target opening to the speed regulation module, and the collaborative controller reduces the second power of the variable speed pumped-storage unit to zero according to a preset slope, and the target speed and the target opening correspond to the second power, so as to synchronously adjust the guide vane opening of the pump turbine in the variable speed pumped-storage unit, and the speed of the variable speed pumped-storage unit.

[0117] When the reactive power of the variable speed pumped storage unit drops to zero, the monitoring module outputs a disconnection instruction to the switch module to instruct the switch module to disconnect, and the variable speed pumped storage unit is disconnected from the grid (deconnected); the monitoring module controls the valve body assembly to close, and the variable speed pumped storage unit exhausts and returns water. The monitoring module can also be used to reset the working mode of the collaborative controller, excitation module and speed regulation module.

[0118] In the embodiment of the present application, when the variable speed pumped storage unit is changed from the power generation phase adjustment condition to the transit shutdown condition, through the cooperation and coordination of the monitoring module, the collaborative controller, the excitation module and the speed regulation module, when the guide vane opening of the pump turbine is the target opening and the variable speed pumped storage unit is operating at the target speed, the first power and the second power, the monitoring module instructs the switch module to disconnect, instructs the excitation module to de-excite, and instructs the speed regulation module to close the guide vanes of the pump turbine, and the monitoring module controls the valve body assembly to close, thereby achieving a smooth conversion of the variable speed pumped storage unit from the power generation phase adjustment condition to the transit shutdown condition, reducing the impact on the variable speed pumped storage unit itself and the power grid, and improving the operating stability of the variable speed pumped storage unit.

[0119] In one of the embodiments, the variable speed pumped storage unit further comprises a valve body assembly, which is arranged at the water inlet end of the pump turbine;

[0120] When the first operating condition is the power generation phase adjustment condition and the second operating condition is the power generation condition, before the excitation module and the speed regulation module receive the control mode setting instruction, the monitoring module confirms that the speed regulation module is in the opening control mode and confirms that the excitation module is in the speed control mode.

[0121] The cooperative controller outputs a preset opening (zero opening target) to the speed regulating module to instruct the speed regulating module to adjust the guide vane opening of the pump turbine based on the preset opening; the cooperative controller outputs a phase-adjusting speed to the excitation module to instruct the excitation module to instruct the variable speed pumped storage unit to operate based on the phase-adjusting speed as the operation target;

[0122] When the speed of the variable speed pumped storage unit is greater than or equal to the phase adjustment speed, the monitoring module controls the valve body assembly to open; the collaborative controller outputs the target opening to the speed regulation module to instruct the speed regulation module to adjust the guide vane opening of the pump turbine based on the target opening.

[0123] Among them, the preset opening corresponding to the power generation condition can be a zero target opening, that is, the opening is zero; the phase modulation speed can be set according to actual conditions and is not limited in the embodiments of the present application.

[0124] Specifically, when the variable speed pumped storage unit changes from the power generation phase adjustment condition to the power generation condition, it can be known from the above that at this time, the speed regulating module is in the opening control mode, and the excitation module is in the speed control mode. After the monitoring module completes the confirmation, the cooperative controller outputs the preset opening to the speed regulating module to instruct the speed regulating module to adjust the guide vane opening of the pump turbine based on the preset opening; the cooperative controller outputs the phase adjustment speed to the excitation module to instruct the excitation module to instruct the variable speed pumped storage unit to operate according to the phase adjustment speed as the operating target; when the speed of the variable speed pumped storage unit is maintained at (greater than or equal to) the phase adjustment speed, the monitoring module controls the variable speed pumped storage unit to exhaust and return water to build pressure, and controls the valve body assembly to open;

[0125] The monitoring module outputs the working mode setting instruction and the active power instruction to the collaborative controller, wherein, because the second operating condition is the power generation condition, the active power instruction is a zero active power instruction, and the second power is zero; the collaborative controller sends the optimal speed instruction (including the target speed) and the optimal opening instruction (target opening) output by searching for the optimal output to the excitation module or the speed regulation module based on the changing second power (reduced to zero with a preset slope) and the unit operation characteristic curve, so as to adjust the guide vane opening of the pump turbine according to the target opening, and adjust the speed of the variable speed pumped storage unit according to the target speed; wherein, the preset slope can be set according to actual conditions and is not limited in the embodiments of the present application.

[0126] It should be noted that, according to the control modes of the excitation module and the speed regulation module, when the excitation module is in the power control mode and the speed regulation module is in the speed control mode, the collaborative controller outputs the active power command to the excitation module, and outputs the target speed and the target opening to the speed regulation module; when the excitation module is in the speed control mode and the speed regulation module is in the power control mode, the collaborative controller outputs the target speed to the excitation module, and outputs the active power command and the target opening to the speed regulation module, and the collaborative controller gradually increases the second power of the variable speed pumped-storage unit according to a preset slope, and the target speed and the target opening correspond to the second power, so as to synchronously adjust the guide vane opening of the pump turbine in the variable speed pumped-storage unit and the speed of the variable speed pumped-storage unit, so that the variable speed pumped-storage unit smoothly enters the power generation condition.

[0127] In an embodiment of the present application, when the variable speed pumped-storage unit is changed from a power generation phase adjustment condition to a power generation condition, the monitoring module, the collaborative controller, the excitation module and the speed regulation module cooperate and coordinate with each other. When the first condition is the power generation phase adjustment condition and the second condition is the power generation condition, before the excitation module and the speed regulation module receive the control mode setting instruction, the collaborative controller outputs a preset opening and a phase adjustment speed to the speed regulation module and the excitation module respectively, so as to adjust the guide vane opening of the pump turbine and the speed of the variable speed pumped-storage unit. When the speed of the variable speed pumped-storage unit is greater than or equal to the phase adjustment speed, the monitoring module controls the valve body assembly to open, thereby realizing a smooth conversion of the variable speed pumped-storage unit from the power generation phase adjustment condition to the power generation condition, and improving the operating stability of the variable speed pumped-storage unit.

[0128] In one of the embodiments, the variable speed pumped storage unit further comprises a valve body assembly, which is arranged at the water inlet end of the pump turbine;

[0129] When the first working condition is a transfer shutdown condition and the second working condition is a self-starting condition, the speed regulating module is also used to enter the opening control mode based on the control mode setting instruction, the excitation module enters the speed control mode based on the control mode setting instruction, and the monitoring module controls the valve body assembly to close;

[0130] The cooperative controller outputs the target speed to the excitation module, and the excitation module adjusts the speed of the variable speed pumped storage unit according to the target speed;

[0131] The collaborative controller outputs the target opening (zero opening target) to the speed regulating module, and the speed regulating module adjusts the guide vane opening of the pump turbine according to the target opening;

[0132] When the speed of the variable speed pumped storage unit is greater than or equal to a preset multiple of the target speed, the monitoring module outputs a shutdown command to the excitation module to instruct the excitation module to de-excite.

[0133] Among them, the preset multiple can be set according to actual conditions. In the embodiment of the present application, the preset multiple of 1.05 is taken as an example for explanation.

[0134] Specifically, when the variable speed pumped storage unit changes from the transit shutdown condition to the self-starting condition, the monitoring module outputs the working mode setting instructions to the speed regulation module, the excitation module and the cooperative controller respectively, so as to instruct the speed regulation module to enter the phase adjustment working mode, instruct the excitation module to enter the self-starting mode in the pumping direction (or the power generation direction), and instruct the cooperative controller to enter the phase adjustment working mode in the pumping direction (or the power generation direction); the monitoring module outputs the control mode setting instructions to the speed regulation module, the excitation module and the cooperative controller respectively, the cooperative controller enters the speed priority mode based on the control mode setting instructions, the speed regulation module enters the opening control mode based on the control mode setting instructions, and the excitation module enters the speed control mode based on the control mode setting instructions.

[0135] At this time, since the second operating condition is a self-starting condition, the final value of the starting speed stored in the cooperative controller can be output as the target speed to the excitation module, and the zero target opening stored in the cooperative controller can be output as the target opening to the speed regulation module. The monitoring module operates the stator side short-circuit switch to close, and controls the valve body assembly to close, and the variable speed pumped storage unit is inflated and pressurized. The monitoring module outputs a starting instruction to the excitation module and the speed regulation module. The excitation module adjusts the speed of the variable speed pumped storage unit according to the target speed, and the speed regulation module adjusts the guide vane opening of the pump turbine according to the target opening.

[0136] When the speed of the variable speed pumped storage unit reaches (is greater than or equal to) a preset multiple of the target speed, the monitoring module outputs a shutdown command to the excitation module to instruct the excitation module to de-excite.

[0137] Exemplarily, the final value of the starting speed may be set in the collaborative controller, and the final value of the starting speed stored in the collaborative controller may also be set by the monitoring module.

[0138] It should be noted that during the process of entering the self-starting condition, the excitation module controls the speed of the unit (variable speed pumped storage unit) so that the unit speed gradually reaches the target speed from rest. Before entering the self-starting condition, water must be pressed and the impeller must start rotating in the air; after a successful self-start, the variable speed pumped storage unit is connected to the grid, which actually enters the phase-shifting condition. Therefore, setting the cooperative controller to the phase-shifting working mode in the pumping direction (or power generation direction) is to notify the cooperative controller that it will enter the phase-shifting condition after a successful self-start, so that the cooperative controller can prepare the speed command required for the phase-shifting condition; the monitoring module sets the cooperative controller to the speed priority mode because after a successful self-start, the grid will enter the phase-shifting condition, and the excitation module controls according to the speed under the phase-shifting condition (speed control mode).

[0139] In the embodiment of the present application, when the variable speed pumped storage unit is changed from the transit shutdown condition to the self-starting condition, the monitoring module, the cooperative controller, the excitation module and the speed regulating module cooperate and coordinate with each other, and the cooperative controller outputs active power instructions, target opening and target speed to the speed regulating module and the excitation module respectively, so as to adjust the guide vane opening of the pump turbine, adjust the speed of the variable speed pumped storage unit, and instruct the variable speed pumped storage unit to operate with the second power as the operating target. When the speed of the variable speed pumped storage unit is greater than or equal to a preset multiple of the target speed, the monitoring module outputs a shutdown instruction to the excitation module to instruct the excitation module to de-excite, thereby realizing a smooth conversion of the variable speed pumped storage unit from the transit shutdown condition to the self-starting condition, reducing the impact on the variable speed pumped storage unit itself and the power grid, and improving the operating stability of the variable speed pumped storage unit.

[0140] In one of the embodiments, the variable speed pumped storage unit further comprises a motor module and a switch module, the motor module is respectively connected to the excitation module and the pump turbine, and the motor module is connected to the power grid through the switch module;

[0141] When the first operating condition is a self-starting condition and the second operating condition is a phase adjustment condition, wherein the phase adjustment condition includes a power generation phase adjustment condition and a pumping phase adjustment condition, the speed regulation module is also used to enter the opening control mode based on the control mode setting instruction; the monitoring module outputs a startup instruction to the excitation module to instruct the excitation module to start running and establish the stator voltage of the variable speed pumped storage unit; the monitoring module is also used to obtain the electric energy information at both ends of the switch module, and when the electric energy information meets the preset conditions, the monitoring module outputs a synchronization instruction to the switch module to instruct the switch module to close;

[0142] The excitation module enters the speed control mode based on the control mode setting instruction, and the speed regulation module is also used to enter the opening control mode based on the control mode setting instruction;

[0143] The cooperative controller outputs the target speed to the excitation module to instruct the excitation module to operate the variable speed pumped storage unit based on the target speed as the operating target. The cooperative controller outputs the target opening (zero opening target) to the speed regulation module, and the speed regulation module adjusts the guide vane opening of the pump turbine based on the target opening.

[0144] Among them, the preset conditions can be set according to actual conditions and are not limited in the embodiments of the present application; the preset conditions corresponding to different working conditions can be the same or different and are not limited in the embodiments of the present application.

[0145] Specifically, Figure 4 As shown, when the variable speed pumped storage unit changes from the self-starting condition to the phase adjustment condition, the monitoring module outputs the working mode setting instruction to the excitation module to instruct the excitation module to enter the power generation direction (or pumping direction) working mode; during the idling deceleration process, the monitoring module outputs the start-up instruction to the excitation module to instruct the excitation module to start running, the excitation module performs excitation input, establishes the stator voltage and makes the stator voltage track the system bus voltage, that is, tracks the bus voltage to adjust the stator voltage, so that the amplitude, frequency and phase of the stator voltage and the bus voltage are basically consistent; a synchronization device can be provided in the monitoring module, the synchronization device can obtain the power information (voltage, current) at both ends of the switch module, and when the power information meets the preset conditions, outputs the synchronization instruction to the switch module to instruct the switch module to close, the variable speed pumped storage unit is connected to the power grid (grid-connected), and the variable speed pumped storage unit enters the power generation (or pumping) phase adjustment condition operation.

[0146] It should be noted that the idling speed reduction process is the process of reducing the speed of the rotating part of the variable speed pumped storage unit (including the rotor of the motor module and the impeller of the water pump turbine). After the variable speed pumped storage unit enters the self-starting condition, the impeller of the water pump turbine rotates in the air (the guide vane is in the closed state), there is no mechanical motive force, and the variable speed pumped storage unit is not connected to the grid, so the speed gradually decreases due to air friction and mechanical friction losses.

[0147] The monitoring module outputs control mode setting instructions to the excitation module and the speed regulation module respectively, to instruct the excitation module to enter the speed control mode, and the speed regulation module to enter the opening control mode; because the second operating condition is the phase adjustment condition, the cooperative controller can output the phase adjustment speed (set according to actual conditions) stored in the cooperative controller as the target speed to the excitation module, and output the zero target opening or small opening target (set according to actual conditions) stored in the cooperative controller as the target opening to the speed regulation module, to instruct the excitation module to instruct the variable speed pumped storage unit to operate according to the target speed as the operating target, and the speed regulation module adjusts the guide vane opening of the pump turbine based on the target opening; the monitoring module outputs a reactive command to the excitation module, and the excitation module controls the reactive power of the variable speed pumped storage unit according to the reactive power contained in the reactive command.

[0148] In the embodiment of the present application, when the variable speed pumped storage unit is changed from a self-starting condition to a phase adjustment condition, the monitoring module, the cooperative controller, the excitation module and the speed regulation module cooperate and coordinate with each other, the monitoring module outputs a control mode setting instruction to the excitation module and the speed regulation module, instructing the excitation module to enter a speed control mode, and the speed regulation module to enter an opening control mode, and the cooperative controller outputs a target speed and a target opening respectively, to instruct the excitation module to instruct the variable speed pumped storage unit to operate according to the target speed as the operating target, the speed regulation module adjusts the guide vane opening of the pump turbine based on the target opening, and indicates that the switch module is closed when the acquired electric energy information meets the preset conditions, thereby realizing a smooth conversion of the variable speed pumped storage unit from a self-starting condition to a phase adjustment condition, reducing the impact on the variable speed pumped storage unit itself and the power grid, and improving the operating stability of the variable speed pumped storage unit.

[0149] In one of the embodiments, the variable speed pumped storage unit further comprises a valve body assembly, which is arranged at the water inlet end of the pump turbine;

[0150] When the first working condition is the pumping phase adjustment working condition and the second working condition is the pumping working condition, before the excitation module and the speed regulating module receive the control mode setting instruction, the monitoring module confirms that the speed regulating module is in the opening control mode and confirms that the excitation module is in the speed control mode.

[0151] The cooperative controller outputs a preset opening (zero opening target) to the speed regulating module to instruct the speed regulating module to adjust the guide vane opening of the pump turbine based on the preset opening; the cooperative controller outputs a phase-adjusting speed to the excitation module to instruct the excitation module to instruct the variable speed pumped storage unit to operate based on the phase-adjusting speed as the operation target;

[0152] When the speed of the variable speed pumped storage unit is greater than or equal to the phase adjustment speed, the monitoring module controls the valve body assembly to open;

[0153] The collaborative controller performs optimization according to the minimum input power corresponding to the current head of the pump-turbine and the unit operation characteristic curve to obtain the second speed, the second opening and the minimum opening. The collaborative controller outputs the second speed to the excitation module, and the excitation module adjusts the speed of the variable speed pumped storage unit according to the second speed; the collaborative controller outputs the minimum opening to the speed regulating module, and the speed regulating module adjusts the guide vane opening of the pump-turbine according to the minimum opening;

[0154] When the time interval between the moment when the speed of the variable speed pumped storage unit reaches the second speed and the current moment is equal to the delay time, the collaborative controller outputs the second opening as the target opening to the speed regulation module.

[0155] Among them, the delay duration can be set according to actual conditions and is not limited in the embodiments of the present application. The delay duration can be used to characterize the time required to wait for the flow channel to be basically stable after the guide vane is opened; the phase adjustment speed and the preset opening can be set according to actual conditions. In the embodiments of the present application, the preset opening is zero opening as an example for explanation.

[0156] Specifically, when the variable speed pumped storage unit changes from the pumping phase adjustment condition to the pumping condition, it can be seen from the above that the excitation module is in the speed control mode and the speed regulation module is in the opening control mode. After the monitoring module completes the confirmation of the control mode of the excitation module and the speed regulation module, the cooperative controller outputs the preset opening (zero opening target) to the speed regulation module to instruct the speed regulation module to adjust the guide vane opening of the pump turbine based on the preset opening; the cooperative controller outputs the phase adjustment speed to the excitation module to instruct the excitation module to instruct the variable speed pumped storage unit to operate according to the phase adjustment speed as the operation target; the monitoring module obtains the speed of the variable speed pumped storage unit, and when the speed reaches (greater than or equal to) the phase adjustment speed, the control valve body assembly is opened to instruct the variable speed pumped storage unit to exhaust and return water to build pressure. It should be noted that the phase adjustment speed is greater than or equal to the minimum speed corresponding to the head of the current pump turbine.

[0157] The monitoring module outputs the working mode setting instruction to the cooperative controller, and the cooperative controller enters the pumping mode. The cooperative controller sets the minimum input power corresponding to the current head of the pump turbine and the unit operation characteristic curve (such as Figure 3The cooperative controller outputs the second speed to the excitation module, and the excitation module adjusts the speed of the variable speed pumped storage unit according to the second speed; the cooperative controller outputs the minimum opening to the speed regulating module, and the speed regulating module adjusts the guide vane opening of the pump turbine according to the minimum opening; when the monitoring module detects that the speed of the variable speed pumped storage unit reaches the second speed, the monitoring module outputs the working mode setting instruction to the speed regulating module, the speed regulating module enters the pumping mode, and the variable speed pumped storage unit enters the pumping working mode. In this case, after the speed of the variable speed pumped storage unit reaches the second speed and a delay time passes, the cooperative controller outputs the second opening as the target opening to the speed regulation module; wherein, before the second opening is used as the target opening, the excitation module remains in the speed control mode to maintain the speed of the variable speed pumped storage unit. When the guide vane is opened and the flow channel is basically stable, the variable speed pumped storage unit enters the pumping condition. At this time, the monitoring module can instruct the excitation module and the speed regulation module to enter the corresponding control mode according to the control mode setting instruction (dispatching operation instruction).

[0158] For example, the input power corresponding to the current head of the pump turbine may be the minimum input power corresponding to the current head of the pump turbine, and the collaborative controller may combine the minimum input power and the current head to generate a Figure 2 , Figure 3 The unit operation characteristic curve shown is used to interpolate and calculate the optimal speed (second speed) and optimal opening (second opening) corresponding to the minimum input through table lookup. The minimum opening can be the minimum opening corresponding to the pumping condition.

[0159] The cooperative controller outputs the active power instruction to the excitation module and the target opening (second opening) to the speed regulating module according to the control modes of the excitation module and the speed regulating module. When the excitation module is in the power control mode and the speed regulating module is in the opening control mode, the cooperative controller outputs the target speed to the excitation module and the target opening to the speed regulating module. The cooperative controller reduces or increases the second power of the variable speed pumped-storage unit according to a preset slope. The target speed may correspond to the second power to adjust the guide vane opening of the pump turbine in the variable speed pumped-storage unit and the speed of the variable speed pumped-storage unit, so as to enable the variable speed pumped-storage unit to smoothly enter the pumping condition.

[0160] In the embodiment of the present application, when the variable speed pumped storage unit is changed from the pumping phase adjustment condition to the pumping condition, the monitoring module, the collaborative controller, the excitation module and the speed regulating module cooperate and coordinate with each other, and the collaborative controller outputs the preset opening and the phase adjustment speed to the speed regulating module and the excitation module respectively, so as to instruct the speed regulating module to adjust the guide vane opening of the pump turbine based on the preset opening, and the excitation module instructs the variable speed pumped storage unit to operate according to the phase adjustment speed as the operating target. When the speed of the variable speed pumped storage unit is greater than or equal to the phase adjustment speed, the monitoring module controls the valve body assembly to open, and the collaborative controller controls the excitation module and the speed regulating module according to the minimum input power corresponding to the current head of the pump turbine, thereby realizing a smooth conversion of the variable speed pumped storage unit from the pumping phase adjustment condition to the pumping condition, and improving the operating stability of the variable speed pumped storage unit.

[0161] In one embodiment, the variable speed pumped storage unit further comprises a valve body assembly, a motor module and a switch module, wherein the valve body assembly is arranged at the water inlet end of the water pump turbine; the motor module is respectively connected to the excitation module and the water pump turbine, and the motor module is connected to the power grid through the switch module;

[0162] When the first operating condition is the pumping operating condition and the second operating condition is the transfer shutdown operating condition, the monitoring module outputs the minimum input power corresponding to the current head of the pump-turbine as the second power to the collaborative controller, and when the guide vane opening of the pump-turbine is the target opening and the variable speed pumped storage unit operates at the target speed, the first power and the second power, the monitoring module outputs a speed control instruction to the excitation module to instruct the excitation module to enter the speed control mode, and the monitoring module outputs a shutdown instruction (guide vane closing instruction) to the speed regulating module to instruct the speed regulating module to close the guide vanes of the pump-turbine;

[0163] When the active power and reactive power corresponding to the variable speed pumped storage unit are both less than the preset values, the monitoring module outputs a de-energizing command to the switch module to instruct the switch module to disconnect, the monitoring module outputs a shutdown command to the excitation module to instruct the excitation module to de-energize, and the monitoring module controls the valve body assembly to close.

[0164] Among them, the preset value can be set according to actual conditions and is not limited in the embodiments of the present application.

[0165] Specifically, Figure 4As shown, when the variable speed pumped storage unit changes from the pumping condition to the transfer shutdown condition, the monitoring module outputs an active load reduction instruction to the cooperative controller to instruct the cooperative controller to gradually reduce the active power of the variable speed pumped storage unit to the minimum input value (input power) corresponding to the current head. In this process, the cooperative controller outputs the second power (input power), the target speed and the target opening to the excitation module and the speed regulating module respectively, so as to realize that the guide vane opening of the pump turbine is the target opening, and the variable speed pumped storage unit operates at the target speed, the first power and the second power. The cooperative controller is based on the control modes of the excitation module and the speed regulating module. When the excitation module is in the power control mode and the speed regulating module is in the opening control mode, The cooperative controller outputs the active power instruction to the excitation module, and outputs the target opening to the speed regulation module; when the excitation module is in the speed control mode and the speed regulation module is in the opening control mode, the cooperative controller outputs the target speed to the excitation module, and outputs the target opening to the speed regulation module, and the cooperative controller reduces the second power of the variable speed pumped storage unit according to a preset slope, and the target speed can correspond to the second power to adjust the guide vane opening of the pump turbine in the variable speed pumped storage unit, and the speed of the variable speed pumped storage unit; the monitoring module outputs the reactive power instruction to the excitation module, because the second operating condition is the transfer shutdown condition, the reactive power instruction is a zero reactive power instruction, and the excitation module gradually reduces the reactive power of the variable speed pumped storage unit to zero at a preset slope.

[0166] Exemplarily, the input power (minimum input) corresponding to the current lift can be obtained by an existing method, which is not limited in the embodiments of the present application.

[0167] When the guide vane opening of the pump-turbine is the target opening and the variable speed pumped storage unit operates at the target speed, the first power and the second power, the monitoring module outputs a speed control instruction to the excitation module to instruct the excitation module to enter the speed control mode, and the monitoring module outputs a shutdown instruction to the speed regulation module to instruct the speed regulation module to close the guide vane of the pump-turbine.

[0168] When the active power and reactive power corresponding to the variable speed pumped storage unit are both less than the preset values, the monitoring module outputs a de-energizing command to the switch module to instruct the switch module to disconnect, and the variable speed pumped storage unit is de-energized from the grid. The monitoring module outputs a shutdown command to the excitation module to instruct the excitation module to de-energize, and the monitoring module controls the valve body assembly to close. The monitoring module can also be used to reset the working modes of the collaborative controller, excitation module and speed regulation module.

[0169] In the embodiment of the present application, when the variable speed pumped storage unit is changed from the pumping condition to the transfer shutdown condition, the monitoring module outputs the input power (minimum input) corresponding to the current head of the pump-turbine as the second power to the cooperative controller through the mutual cooperation and coordination of the monitoring module, the cooperative controller, the excitation module and the speed regulating module. When the guide vane opening of the pump-turbine is the target opening and the variable speed pumped storage unit is running at the target speed, the first power and the second power, the monitoring module instructs the excitation module to enter the speed control mode and instructs the speed regulating module to close the guide vanes of the pump-turbine. When the active power and reactive power corresponding to the variable speed pumped storage unit are both less than the preset values, the monitoring module instructs the switch module to disconnect, the excitation module to de-excite, and the control valve body assembly to close, thereby achieving a smooth conversion of the variable speed pumped storage unit from the pumping condition to the transfer shutdown condition, reducing the impact on the variable speed pumped storage unit itself and the power grid, and improving the operating stability of the variable speed pumped storage unit.

[0170] In one of the embodiments, the variable speed pumped storage unit further comprises a valve body assembly, which is arranged at the water inlet end of the pump turbine;

[0171] When the first operating condition is the pumping operating condition and the second operating condition is the pumping phase adjustment operating condition, the monitoring module outputs the minimum input power corresponding to the current head of the pump-turbine as the second power to the cooperative controller, and when the guide vane opening of the pump-turbine is the target opening and the variable speed pumped storage unit operates at the target speed, the first power and the second power, the cooperative controller outputs a preset power instruction to the excitation module, and the excitation module adjusts the active power corresponding to the variable speed pumped storage unit to a preset size based on the preset power instruction; the monitoring module outputs a speed control instruction to the excitation module to instruct the excitation module to enter the speed control mode, and the monitoring module outputs a shutdown instruction to the speed regulation module to instruct the speed regulation module to close the guide vanes of the pump-turbine;

[0172] The cooperative controller outputs the phase-adjusting speed to the excitation module to instruct the excitation module to instruct the variable speed pumped storage unit to operate according to the phase-adjusting speed as the operating target. When the speed of the variable speed pumped storage unit is greater than or equal to the phase-adjusting speed, the monitoring module outputs a closing command to the speed regulating module to instruct the speed regulating module to close the guide vanes of the pump turbine, and the monitoring module controls the valve body assembly to close.

[0173] Among them, the phase modulation speed and the preset power can be set according to actual conditions and are not limited in the embodiments of the present application.

[0174] Specifically, when the variable speed pumped storage unit changes from the pumping condition to the pumping phase adjustment condition, the monitoring module outputs an active load reduction instruction to the cooperative controller to instruct the cooperative controller to gradually reduce the active power of the variable speed pumped storage unit to the minimum input value (input power) corresponding to the current head. During this process, the cooperative controller outputs the second power (input power), the target speed and the target opening to the excitation module and the speed regulation module respectively, so as to realize the guide vane opening of the pump turbine to be the target opening, and the variable speed pumped storage unit to operate at the target speed, the first power and the second power. Among them, the cooperative controller is based on the control mode of the excitation module and the speed regulation module. When the excitation module is in the power control mode and the speed regulation module is in the opening control mode, the cooperative controller The controller outputs the active power instruction to the excitation module and the target opening to the speed regulation module; when the excitation module is in the speed control mode and the speed regulation module is in the opening control mode, the cooperative controller outputs the target speed to the excitation module and the target opening to the speed regulation module, and the cooperative controller reduces the second power of the variable speed pumped storage unit according to the preset slope, and the target speed can correspond to the second power to adjust the guide vane opening of the pump turbine in the variable speed pumped storage unit, and the speed of the variable speed pumped storage unit; the monitoring module outputs the preset power instruction to the excitation module. Since the second operating condition is the pumping phase adjustment operating condition, the preset power instruction can be a zero reactive instruction, and the excitation module gradually reduces the reactive power of the variable speed pumped storage unit to zero at a preset slope.

[0175] The monitoring module outputs a speed control instruction to the excitation module to instruct the excitation module to enter the speed control mode. The monitoring module outputs a working mode setting instruction to the cooperative controller, and the cooperative controller enters the pumping phase adjustment mode. The monitoring module outputs a shutdown instruction to the speed regulation module to instruct the speed regulation module to close the guide vanes of the pump turbine. The cooperative controller outputs the phase adjustment speed to the excitation module to instruct the excitation module to instruct the variable speed pumped storage unit to operate according to the phase adjustment speed as the operating target. When the speed of the variable speed pumped storage unit obtained by the monitoring module is greater than or equal to the phase adjustment speed, the monitoring module controls the valve body assembly to close. At this time, the variable speed pumped storage unit is inflated and pressurized to enter the pumping phase adjustment condition.

[0176] In the embodiment of the present application, when the variable speed pumped-storage unit is changed from the pumping condition to the pumping phase adjustment condition, the monitoring module, the cooperative controller, the excitation module and the speed regulating module cooperate and coordinate with each other, and the monitoring module outputs the input power corresponding to the current head of the pump-turbine as the second power to the cooperative controller. When the guide vane opening of the pump-turbine is the target opening, and the variable speed pumped-storage unit is operating at the target speed, the first power and the second power, the monitoring module instructs the excitation module to enter the speed control mode and instructs the speed regulating module to close the guide vanes of the pump-turbine. When the speed of the variable speed pumped-storage unit is greater than or equal to the phase adjustment speed, the monitoring module instructs the speed regulating module to close the guide vanes of the pump-turbine and the control valve body assembly to close, thereby achieving a smooth conversion of the variable speed pumped-storage unit from the pumping condition to the pumping phase adjustment condition, and improving the operating stability of the variable speed pumped-storage unit.

[0177] To facilitate understanding by those skilled in the art, the coordinated control system of a variable speed pumped storage unit is explained below with reference to a specific example, wherein the monitoring module may be a monitoring LCU (Logic Control Unit), the excitation module may be an AC excitation, and the speed regulation module may be a speed regulator.

[0178] The collaborative controller only participates in the control and regulation of the active power of the variable-speed pumped-storage unit. The signals interacting between the collaborative controller and the monitoring LCU, AC excitation and speed regulator also mainly realize the needs of active power control of the variable-speed pumped-storage unit. Signals not related to active power regulation and control do not need to pass through the collaborative controller. The target and mode instructions related to active power are sent by the monitoring LCU to the collaborative controller. After optimizing, the collaborative controller generates the optimal instructions and hands them over to the AC excitation or speed regulator for closed-loop regulation; the AC excitation and speed regulator feed back the mode status signal to the collaborative controller, and the collaborative controller also feeds back the corresponding collaborative control status signal to the monitoring LCU; other signals are directly interacted by the monitoring LCU with the AC excitation or speed regulator, and are not repeated in the embodiments of the present application.

[0179] In the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example.

[0180] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0181] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A coordinated control system for a variable speed pumped storage unit, characterized in that: The system includes a monitoring module, a collaborative controller, an excitation module and a speed regulation module, wherein the monitoring module is respectively connected to the collaborative controller, the excitation module and the speed regulation module, and the collaborative controller is respectively connected to the excitation module and the speed regulation module; wherein: The monitoring module is used for outputting control mode setting instructions corresponding to the second working condition to the excitation module and the speed regulation module, outputting reactive power instructions corresponding to the second working condition to the excitation module, and outputting active power instructions corresponding to the second working condition to the cooperative controller when the variable speed pumped storage unit changes from the first working condition to the second working condition; The excitation module is used to enter the power control mode or the speed control mode based on the control mode setting instruction, and to instruct the variable speed pumped storage unit to operate with the first power included in the reactive power instruction as the operation target; The speed regulating module is used to enter the power control mode or the speed control mode or the opening mode based on the control mode setting instruction; The collaborative controller is used to perform optimization according to the unit operation characteristic curve, the second power included in the active power instruction, and the current water head or lift, obtain the target speed and the target opening, and output the second power, the target speed and the target opening to the excitation module and the speed regulating module respectively according to the control mode of the excitation module and the speed regulating module, so as to adjust the guide vane opening of the water pump turbine in the variable speed pumped storage unit, and instruct the variable speed pumped storage unit to operate with the target speed and the second power as the operation target; Wherein, when the first operating condition is a transfer shutdown condition and the second operating condition is a rotating standby condition, the speed regulating module enters the speed control mode based on the control mode setting instruction; the collaborative controller outputs the target opening and the target speed to the speed regulating module; The monitoring module outputs a startup instruction to the speed regulating module to instruct the speed regulating module to start running; the speed regulating module adjusts the guide vane opening of the pump turbine according to the target opening, and the speed regulating module adjusts the speed of the variable speed pumped storage unit according to the target speed; the target speed is less than the synchronous speed of the variable speed pumped storage unit; When the unit speed is greater than or equal to the target speed of the preset coefficient, the monitoring module outputs the start-up instruction to the excitation module to instruct the excitation module to start running, and the excitation module establishes the stator voltage of the variable speed pumped storage unit according to the system voltage.

2. The system according to claim 1, characterized in that The variable speed pumped storage unit further comprises a motor module and a switch module, wherein the motor module is respectively connected to the excitation module and the pump turbine, and the motor module is connected to the power grid via the switch module; When the first operating condition is a rotating standby operating condition and the second operating condition is a power generation operating condition, before the excitation module and the speed regulation module receive the control mode setting instruction, the monitoring module is further used to obtain the electric energy information at both ends of the switch module, and when the electric energy information meets the preset conditions, the monitoring module outputs a synchronization instruction to the switch module to instruct the switch module to close; After entering the power generation condition, the excitation module enters the power control mode or the speed control mode based on the control mode setting instruction, and the speed regulation module enters the speed control mode or the power control mode based on the control mode setting instruction; the collaborative controller confirms the current control mode of the excitation module and the speed regulation module, and gradually loads the active power of the variable speed pumped storage unit to the target value.

3. The system according to claim 2, characterized in that When the first operating condition is a power generation condition and the second operating condition is a transfer shutdown condition, when the guide vane opening of the pump turbine is the target opening and the variable speed pumped storage unit operates at the target speed, the first power and the second power, the monitoring module outputs a disconnection instruction to the switch module to instruct the switch module to disconnect; The collaborative controller outputs the control mode setting instruction to the speed regulating module again to instruct the speed regulating module to enter the speed control mode; the collaborative controller is also used to obtain the current water head of the variable speed pumped storage unit, the collaborative controller performs optimization according to the unit operation characteristic curve and the water head to obtain a first speed and a first opening, the collaborative controller outputs the first speed and the first opening to the speed regulating module, the speed regulating module adjusts the guide vane opening of the pump turbine according to the first opening, and the speed regulating module adjusts the speed of the variable speed pumped storage unit according to the first speed; The cooperative controller outputs a zero power instruction to the excitation module; The monitoring module outputs shutdown instructions to the speed regulating module and the excitation module respectively, so as to instruct the excitation module to de-excite, and instruct the speed regulating module to close the guide vanes of the water pump turbine.

4. The system according to claim 1, characterized in that The variable speed pumped storage unit further comprises a valve body assembly, and the valve body assembly is arranged at the water inlet end of the water pump turbine; When the first operating condition is a power generation condition and the second operating condition is a power generation phase adjustment condition, when the guide vane opening of the pump-turbine is the target opening and the variable speed pumped-storage unit operates at the target speed, the first power and the second power, the monitoring module outputs an opening control instruction to the speed regulating module to instruct the speed regulating module to enter an opening control mode, the monitoring module outputs a speed control instruction to the excitation module to instruct the excitation module to enter the speed control mode, the cooperative controller outputs a phase adjustment speed to the excitation module to instruct the excitation module to instruct the variable speed pumped-storage unit to operate according to the phase adjustment speed as the operating target, and the cooperative controller outputs a preset opening to the speed regulating module to instruct the speed regulating module to adjust the guide vane opening of the pump-turbine based on the preset opening; When the speed of the variable speed pumped storage unit is greater than or equal to the phase adjustment speed, the monitoring module outputs a closing instruction to the speed regulating module to instruct the speed regulating module to close the guide vanes of the pump turbine, and the monitoring module controls the valve body assembly to close.

5. The system according to claim 1, characterized in that The variable speed pumped storage unit further comprises a valve body assembly, a motor module and a switch module, wherein the motor module is respectively connected to the excitation module and the pump turbine, the motor module is connected to the power grid through the switch module, and the valve body assembly is arranged at the water inlet end of the pump turbine; When the first operating condition is the power generation phase adjustment condition and the second operating condition is the transfer shutdown condition, when the guide vane opening of the pump-turbine is the target opening and the variable speed pumped storage unit operates at the target speed, the first power and the second power, the monitoring module outputs a de-coupling instruction to the switch module to instruct the switch module to disconnect, the monitoring module outputs a shutdown instruction to the speed regulation module and the excitation module respectively to instruct the excitation module to de-excite and instruct the speed regulation module to close the guide vanes of the pump-turbine, and the monitoring module controls the valve body assembly to close.

6. The system according to claim 1, characterized in that The variable speed pumped storage unit further comprises a valve body assembly, and the valve body assembly is arranged at the water inlet end of the water pump turbine; When the first operating condition is a power generation phase adjustment operating condition and the second operating condition is a power generation operating condition, before the excitation module and the speed regulation module receive the control mode setting instruction, the monitoring module confirms that the speed regulation module is in an opening control mode and confirms that the excitation module is in a speed control mode. The cooperative controller outputs a preset opening to the speed regulating module to instruct the speed regulating module to adjust the guide vane opening of the pump turbine based on the preset opening; The cooperative controller outputs the phase-adjusting speed to the excitation module to instruct the excitation module to instruct the variable speed pumped storage unit to operate according to the phase-adjusting speed as the operation target; When the speed of the variable speed pumped storage unit is greater than or equal to the phase adjustment speed, the monitoring module controls the valve body assembly to open; The cooperative controller outputs the target opening to the speed regulating module to instruct the speed regulating module to adjust the guide vane opening of the pump turbine based on the target opening.

7. The system according to claim 1, characterized in that The variable speed pumped storage unit further comprises a valve body assembly, and the valve body assembly is arranged at the water inlet end of the water pump turbine; When the first working condition is a transfer shutdown condition and the second working condition is a self-starting condition, the speed regulating module is further used to enter the opening control mode based on the control mode setting instruction, the excitation module enters the speed control mode based on the control mode setting instruction, and the monitoring module controls the valve body assembly to close; The cooperative controller outputs the target speed to the excitation module, and the excitation module adjusts the speed of the variable speed pumped storage unit according to the target speed; The cooperative controller outputs the target opening to the speed regulating module, and the speed regulating module adjusts the guide vane opening of the pump turbine according to the target opening; When the speed of the variable speed pumped storage unit is greater than or equal to a preset multiple of the target speed, the monitoring module outputs a shutdown command to the excitation module to instruct the excitation module to de-excite.

8. The system according to claim 1, characterized in that The variable speed pumped storage unit further comprises a motor module and a switch module, wherein the motor module is respectively connected to the excitation module and the pump turbine, and the motor module is connected to the power grid via the switch module; When the first operating condition is a self-starting condition and the second operating condition is a phase adjustment condition, wherein the phase adjustment condition includes a power generation phase adjustment condition and a pumping phase adjustment condition, the speed regulation module is further used to enter an opening control mode based on the control mode setting instruction; the monitoring module outputs a startup instruction to the excitation module to instruct the excitation module to start running and establish the stator voltage of the variable speed pumped storage unit; the monitoring module is also used to obtain the electric energy information at both ends of the switch module, and when the electric energy information meets the preset conditions, the monitoring module outputs a synchronization instruction to the switch module to instruct the switch module to close; The excitation module enters the speed control mode based on the control mode setting instruction, and the speed regulation module is also used to enter the opening control mode based on the control mode setting instruction; The collaborative controller outputs the target speed to the excitation module to instruct the excitation module to operate the variable speed pumped storage unit according to the target speed as the operating target. The collaborative controller outputs the target opening to the speed regulation module, and the speed regulation module adjusts the guide vane opening of the pump turbine based on the target opening.

9. The system according to claim 1, characterized in that The variable speed pumped storage unit further comprises a valve body assembly, and the valve body assembly is arranged at the water inlet end of the water pump turbine; When the first working condition is a pumping phase adjustment working condition and the second working condition is a pumping working condition, before the excitation module and the speed regulation module receive the control mode setting instruction, the monitoring module confirms that the speed regulation module is in an opening control mode and confirms that the excitation module is in a speed control mode. The cooperative controller outputs a preset opening to the speed regulating module to instruct the speed regulating module to adjust the guide vane opening of the pump turbine based on the preset opening; The cooperative controller outputs the phase-adjusting speed to the excitation module to instruct the excitation module to instruct the variable speed pumped storage unit to operate according to the phase-adjusting speed as the operation target; When the speed of the variable speed pumped storage unit is greater than or equal to the phase adjustment speed, the monitoring module controls the valve body assembly to open; The collaborative controller performs optimization according to the minimum input power corresponding to the current head of the pump-turbine and the unit operation characteristic curve to obtain a second speed, a second opening and a minimum opening, and the collaborative controller outputs the second speed to the excitation module, and the excitation module adjusts the speed of the variable speed pumped storage unit according to the second speed; The cooperative controller outputs the minimum opening to the speed regulating module, and the speed regulating module adjusts the guide vane opening of the pump turbine according to the minimum opening; When the time interval between the moment when the speed of the variable speed pumped storage unit reaches the second speed and the current moment is equal to the delay time, the collaborative controller outputs the second opening as the target opening to the speed regulation module.

10. The system according to claim 1, characterized in that The variable speed pumped storage unit further comprises a valve body assembly, a motor module and a switch module, wherein the valve body assembly is arranged at the water inlet end of the pump turbine; the motor module is respectively connected to the excitation module and the pump turbine, and the motor module is connected to the power grid through the switch module; When the first operating condition is a pumping operating condition and the second operating condition is a transfer shutdown operating condition, the monitoring module outputs the minimum input power corresponding to the current head of the pump-turbine as the second power to the collaborative controller; when the guide vane opening of the pump-turbine is the target opening and the variable speed pumped storage unit operates at the target speed, the first power and the second power, the monitoring module outputs a speed control instruction to the excitation module to instruct the excitation module to enter the speed control mode; the monitoring module outputs a shutdown instruction to the speed regulating module to instruct the speed regulating module to close the guide vanes of the pump-turbine; When the active power and reactive power corresponding to the variable speed pumped storage unit are both less than the preset values, the monitoring module outputs a de-energizing instruction to the switch module to instruct the switch module to disconnect, the monitoring module outputs the shutdown instruction to the excitation module to instruct the excitation module to de-energize, and the monitoring module controls the valve body assembly to close.

11. The system according to claim 1, characterized in that The variable speed pumped storage unit further comprises a valve body assembly, and the valve body assembly is arranged at the water inlet end of the water pump turbine; When the first operating condition is a pumping operating condition and the second operating condition is a pumping phase adjustment operating condition, the monitoring module outputs the minimum input power corresponding to the current head of the pump-turbine as the second power to the cooperative controller, and when the guide vane opening of the pump-turbine is the target opening, and the variable speed pumped-storage unit operates at the target speed, the first power and the second power, the cooperative controller outputs a preset power instruction to the excitation module, and the excitation module adjusts the active power corresponding to the variable speed pumped-storage unit to a preset size based on the preset power instruction; the monitoring module outputs a speed control instruction to the excitation module to instruct the excitation module to enter the speed control mode, and the monitoring module outputs a shutdown instruction to the speed regulation module to instruct the speed regulation module to close the guide vanes of the pump-turbine; The collaborative controller outputs the phase-adjusting speed to the excitation module to instruct the excitation module to instruct the variable speed pumped-storage unit to operate according to the phase-adjusting speed as the operating target. When the speed of the variable speed pumped-storage unit is greater than or equal to the phase-adjusting speed, the monitoring module controls the valve body assembly to close.

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