A grid-connected speed control system and method for an energy storage hydraulic wind turbine generator set

Abstract

The present invention provides a grid-connected speed control system and method for a storage hydraulic type wind power generation set. The system includes a wind turbine device, a hydraulic transmission device, a hydraulic energy storage device, and a grid-connected power generation device; the wind turbine device is coaxially and rigidly connected to the hydraulic transmission device, the hydraulic transmission device is coaxially and rigidly connected to the hydraulic energy storage device, and the hydraulic energy storage device is coaxially and rigidly connected to the grid-connected power generation device. The present invention adopts a hydraulic energy storage device, which can buffer the impact brought by voltage mutation and ensure the ability of the equipment to operate continuously without tripping off the grid; at the same time, the hydraulic energy storage device can real-time regulate the energy input into the system, coordinate the energy allocation from the root, avoid the damage of redundant energy, and make full use of the redundant energy, absorb energy under the pump control condition, and output energy under the motor condition; the traditional wind speed sensor and flow sensor are omitted, the system has higher flexibility, and the equipment cost is saved.

Description

Technical Field

[0001] The present invention belongs to the technical field of wind power generation, and particularly relates to a grid-connected speed control system and method for a storage hydraulic type wind turbine generator set. Background Technique

[0002] With the increasing severity of environmental and energy problems, wind power generation has attracted more and more attention at home and abroad, and the wind power generation industry has thus developed rapidly. However, affected by climatic conditions, the output power of wind power generation has the characteristics of intermittency and randomness. Large-scale grid connection of wind power generation will not only cause large power fluctuations, but also easily lead to the lack of system inertia and affect the frequency stability of the system. In order to ensure the safe and stable operation of the power system during grid connection, it is necessary to improve the grid-connected speed control effect of wind turbine generators.

[0003] The wind turbine adaptive pitch control system described in US Patent US09347430B2. The adaptive pitch control system of the wind turbine is used for a variable speed doubly-fed induction generator (DFIG) system. An adaptive neural network generates optimized controller gains for pitch control. Intelligent differential evolution of pitch controller parameters, a type of genetic algorithm is generated. Training of a backpropagation neural network uses the generated pitch controller parameters to adjust the weights of the network according to the system state in a variable wind speed environment. The wind energy generator is a doubly-fed induction generator (DFIG), and the constant K is adapted to be connected to the output of the pitch servo. The PI pitch controller output includes means for sending a pitch command to the pitch servo to control the pitch angle; the backpropagation neural network (BPNN) has signals applied to the plurality of signal paths. However, this method uses a BP neural network, which is a global approximation network. Each time sample learning is performed, all the weights of the network need to be readjusted, the convergence speed is slow, it is easy to fall into local minima, and it is difficult to meet the high real-time requirements of the control system.

[0004] A wind turbine generator set intelligent control system and method described in Chinese Patent CN113357083A. This method includes a plurality of edge computing subsystems and at least one wind farm-level computing subsystem that are communicatively connected to each other. Each of the edge computing subsystems is communicatively connected to at least one main control device; each of the main control devices communicates and exchanges data with each of the edge computing subsystems and the wind farm-level computing subsystem, and feeds back the algorithm model operation results of each of the edge computing subsystems and the wind farm-level computing subsystem to each of the main control devices to perform intelligent control and operating state adjustment on the wind turbines corresponding to each of the main control devices, so as to achieve intelligent control of wind power. By collecting and processing multi-dimensional data of the wind turbines, intelligent control and state adjustment of the wind turbines are realized based on the algorithm models deployed inside the wind turbines and the wind farm, and the intelligent algorithm is completed. This method still uses a large number of traditional sensors, which are expensive and the usage method is relatively cumbersome.

[0005] In summary, most of the existing energy storage hydraulic wind turbine grid-connected speed control methods cannot fundamentally solve the problems caused by external disturbances in the system during the control process. Summary of the invention

[0006] In view of the deficiencies in the prior art, the present invention provides a grid-connected speed control system and method for an energy storage hydraulic wind turbine generator set.

[0007] In a first aspect, the present invention provides a grid-connected speed control system for an energy storage hydraulic wind turbine generator set, comprising a wind turbine device, a hydraulic transmission device, a hydraulic energy storage device, and a grid-connected power generation device; the wind turbine device and the hydraulic transmission device, the hydraulic transmission device and the hydraulic energy storage device, and the hydraulic energy storage device and the grid-connected power generation device are coaxially rigidly connected;

[0008] The wind turbine device comprises a wind speed predictor, a wind wheel and a first transmission shaft; the wind wheel is in transmission connection with the first transmission shaft, and the wind speed predictor is located on a side of the wind wheel away from the first transmission shaft;

[0009] The hydraulic transmission device includes a first speed torque sensor, a metering pump, a high-pressure pipeline, a first one-way valve, a second one-way valve, a first overflow valve, an oil replenishment pump, an oil replenishment tank, a safety valve, a flow controller, a speed controller, a variable motor, a second speed torque sensor, a low-pressure pipeline and a power controller;

[0010] The hydraulic energy storage device includes a variable pump motor, an accumulator and an energy storage system oil tank;

[0011] The grid-connected power generation device comprises a generator, a grid-connected cabinet and a power grid;

[0012] The first rotational speed torque sensor is arranged on the first transmission shaft; the main shaft of the fixed displacement pump is in transmission connection with one end of the first transmission shaft away from the wind turbine; the oil inlet of the fixed displacement pump sucks oil from the oil replenishing tank through the low-pressure pipeline, and the oil outlet discharges high-pressure oil through the high-pressure pipeline; the flow controller is arranged on the high-pressure pipeline; the outlet end of the first one-way valve is communicated with the high-pressure pipeline, and the inlet end is communicated with the inlet end of the second one-way valve; the outlet end of the second one-way valve is communicated with the low-pressure pipeline; both ends of the first overflow valve are respectively connected with the oil outlet of the oil replenishing pump and the oil replenishing tank; the oil outlet of the oil replenishing pump is respectively connected with the inlet end of the first one-way valve and the inlet end of the second one-way valve, and the oil inlet is connected with the oil replenishing tank; both ends of the safety valve are respectively connected with the high-pressure pipeline and the low-pressure pipeline; the input end of the rotational speed controller is respectively connected with the flow controller, the second rotational speed torque sensor and the grid connection cabinet, and the output end is connected with the variable motor; the oil inlet of the variable motor is connected with the high-pressure pipeline, and the oil outlet is connected with the low-pressure pipeline; the main shaft of the variable motor is coaxially connected with the main shaft of the generator through the second transmission shaft; the generator generates electricity and inputs electric energy to the power grid; the grid connection cabinet is installed between the generator and the power grid; the second rotational speed torque sensor is installed on the second transmission shaft; the variable pump motor is connected with the energy storage system oil tank and is connected with the accumulator through the energy storage pipeline, so that the accumulator stores and releases energy in different states; the input end of the power controller is respectively connected with the wind speed predictor, the first rotational speed torque sensor, the second rotational speed torque sensor and the grid connection cabinet, and the output end is connected with the variable pump motor.

[0013] In a second aspect, the present invention provides a grid connection rotational speed control method for a storage type hydraulic wind power generation set, which is applied to the grid connection rotational speed control system of the storage type hydraulic wind power generation set described in the first aspect. The control method includes:

[0014] When the storage type hydraulic wind power generation set is disturbed, the rotational speed controller collects the rotational speed of the variable motor through the second rotational speed torque sensor, the flow controller collects the flow of the high-pressure pipeline, and the grid connection cabinet collects the frequency and voltage of the power grid. Then the rotational speed controller outputs a control signal to the variable motor to realize the control of the swing angle of the variable motor, change the displacement of the variable motor, so that the oil pressure of the high-pressure oil in the high-pressure pipeline of the hydraulic transmission part also changes accordingly, thereby changing the rotational speed of the fixed displacement pump and releasing the energy stored in the wind turbine.

[0015] The power controller collects the wind speed through a wind speed predictor, the first rotational speed and torque sensor collects the rotational speed of the wind turbine, outputs the impeller torque, the second rotational speed and torque sensor collects the generator torque, the grid connection cabinet collects the generator output power and the grid voltage, and then the power controller outputs a control signal to the variable pump motor of the hydraulic energy storage device to make the variable pump motor operate in the motor condition, input high-pressure oil into the accumulator, and the power controller increases the swashplate angle of the variable pump motor to quickly release the energy in the accumulator;

[0016] When the disturbance is eliminated, the speed controller plans the displacement of the variable motor, and the power controller simultaneously plans the displacement action instruction of the variable pump motor of the hydraulic energy storage system, so that the variable pump motor stores and releases energy in the motor condition, adjusts the output power of the unit, and dynamically injects power into the grid to achieve the grid-side frequency response.

[0017] The present invention provides a grid-connected speed control system and method for a hydraulic energy storage type wind power generation unit. The system includes a wind turbine device, a hydraulic transmission device, a hydraulic energy storage device, and a grid-connected power generation device; the wind turbine device is coaxially and rigidly connected to the hydraulic transmission device, the hydraulic transmission device is coaxially and rigidly connected to the hydraulic energy storage device, and the hydraulic energy storage device is coaxially and rigidly connected to the grid-connected power generation device. The present invention adopts a hydraulic energy storage device, which can buffer the impact caused by voltage mutation and ensure the ability of the equipment to operate continuously without tripping off the grid; at the same time, the hydraulic energy storage device can adjust the energy input into the system in real time, coordinate the energy allocation from the source, avoid the damage of redundant energy, and make full use of the redundant energy, absorb energy in the pump control condition, and output energy in the motor condition; the traditional wind speed sensor and flow sensor are omitted, the system has higher flexibility and saves equipment costs. In addition, different from the traditional intelligent control algorithm, it increases the real-time performance and effectiveness of the operation result of the algorithm model participating in the control, avoids the risk of wind farm data leakage, and saves the network transmission cost of data transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative efforts.

[0019] Figure 1 It is a schematic structural diagram of a grid-connected speed control system for a hydraulic energy storage type wind power generation unit provided in a part of the embodiments of the present invention;

[0020] Figure 2 It is a working flow chart of a grid-connected speed control method for a hydraulic energy storage type wind power generation unit provided in a part of the embodiments of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0022] As Figure 1 shown, a grid-connected speed control system for a storage hydraulic type wind turbine generator set provided in a part of the embodiments of the present invention includes a wind turbine device, a hydraulic transmission device, a hydraulic energy storage device, and a grid-connected power generation device; the wind turbine device is coaxially and rigidly connected to the hydraulic transmission device, the hydraulic transmission device is coaxially and rigidly connected to the hydraulic energy storage device, and the hydraulic energy storage device is coaxially and rigidly connected to the grid-connected power generation device;

[0023] The wind turbine device includes a wind speed predictor 1, a wind wheel 2, and a first transmission shaft 3; the wind wheel 2 is drivingly connected to the first transmission shaft 3, and the wind speed predictor 1 is located on a side of the wind wheel 2 away from the first transmission shaft 3;

[0024] The hydraulic transmission device includes a first rotational speed torque sensor 4, a fixed displacement pump 5, a high-pressure pipeline 6, a first check valve 7, a second check valve 8, a first relief valve 9, a makeup oil pump 10, a makeup oil tank 11, a safety valve 12, a flow controller 13, a speed controller 14, a variable motor 15, a second rotational speed torque sensor 16, a low-pressure pipeline 24, and a power controller 25;

[0025] The hydraulic energy storage device includes a variable pump motor 17, an accumulator 18, and an energy storage system oil tank 19;

[0026] The grid-connected power generation device includes a generator 20, a grid connection cabinet 21, and a power grid 22;

[0027] The first rotational speed and torque sensor 4 is arranged on the first transmission shaft 3; the main shaft of the fixed displacement pump 5 is in transmission connection with one end of the first transmission shaft 3 away from the wind turbine 2; the oil inlet of the fixed displacement pump 5 sucks oil from the oil replenishing tank 11 through the low-pressure pipeline 24, and the oil outlet discharges high-pressure oil through the high-pressure pipeline 6; a flow controller 13 is arranged on the high-pressure pipeline 6; the outlet end of the first one-way valve 7 is communicated with the high-pressure pipeline 6, and the inlet end is communicated with the inlet end of the second one-way valve 8; the outlet end of the second one-way valve 8 is communicated with the low-pressure pipeline 24; both ends of the first overflow valve 9 are respectively connected with the oil outlet of the oil replenishing pump 10 and the oil replenishing tank 11; the oil outlet of the oil replenishing pump 10 is respectively connected with the inlet end of the first one-way valve 7 and the inlet end of the second one-way valve 8, and the oil inlet is connected with the oil replenishing tank 11; both ends of the safety valve 12 are respectively connected with the high-pressure pipeline 6 and the low-pressure pipeline 24; the input end of the speed controller 14 is respectively connected with the flow controller 13, the second rotational speed and torque sensor 16 and the grid connection cabinet 21, and the output end is connected with the variable motor 15; the oil inlet of the variable motor 15 is connected with the high-pressure pipeline 6, and the oil outlet is connected with the low-pressure pipeline 24; the main shaft of the variable motor 15 is coaxially connected with the main shaft of the generator 20 through the second transmission shaft 26; the generator 20 generates electricity and inputs electric energy to the power grid 22; a grid connection cabinet 21 is installed between the generator 20 and the power grid 22; the second rotational speed and torque sensor 16 is installed on the second transmission shaft 26; the variable pump motor 17 is connected with the energy storage system oil tank 19 and is connected with the accumulator 18 through the energy storage pipeline 23, so that the accumulator 18 stores and releases energy in different states; the input end of the power controller 25 is respectively connected with the wind speed predictor 1, the first rotational speed and torque sensor 4, the second rotational speed and torque sensor 16 and the grid connection cabinet 21, and the output end is connected with the variable pump motor 17.

[0028] As Figure 2 shown, the embodiment of the present invention further provides a grid connection speed control method for an energy storage type hydraulic wind turbine generator set, which is applied to the grid connection speed control system of the energy storage type hydraulic wind turbine generator set. The control method includes: when the energy storage type hydraulic wind turbine generator set is disturbed, the speed controller 14 collects the rotational speed of the variable motor 15 through the second rotational speed and torque sensor 16, the flow controller 13 collects the flow of the high-pressure pipeline 6, and the grid connection cabinet 21 collects the frequency and voltage of the power grid 22. Then the speed controller 14 outputs a control signal to the variable motor 15 to realize the swashplate angle control of the variable motor 15, change the displacement of the variable motor 15, so that the oil pressure of the high-pressure oil in the high-pressure pipeline 6 of the hydraulic transmission part also changes accordingly, thereby changing the rotational speed of the fixed displacement pump 5 and releasing the energy stored in the wind turbine.

[0029] The power controller 25 collects the wind speed through the wind speed predictor 1, the first rotational speed torque sensor 4 collects the rotational speed of the wind turbine 2 and outputs the impeller torque, the second rotational speed torque sensor 16 collects the torque of the generator 20, and the grid connection cabinet 21 collects the output power of the generator 20 and the grid voltage. Then, the power controller 25 outputs a control signal to the variable pump motor 17 of the hydraulic energy storage device, causing the variable pump motor 17 to operate in the motor mode and input high-pressure oil into the accumulator 18. The power controller 25 increases the swashplate angle of the variable pump motor 17, thereby rapidly releasing the energy in the accumulator 18;

[0030] After the disturbance is eliminated, the speed controller 14 plans the displacement of the variable motor 15, and the power controller 25 simultaneously plans the displacement action command of the variable pump motor 17 of the hydraulic energy storage system, enabling the variable pump motor 17 to store and release energy in the motor mode, adjusting the output power of the unit, and dynamically injecting power into the power grid 22 to achieve grid-side frequency response.

[0031] The wind speed predictor 1 uses a neural network with an RBF function to predict the wind speed. Grid connection speed control process: The flow controller 13 based on a neural network with an RBF function and a nonlinear extended state observer.

[0032] First, analyze the influence of a series of problems such as model uncertainty, parameter time-variation, and system external disturbances on the motor speed control system, and obtain the nonlinearity of the pump-controlled vane motor speed control system as follows:

[0033]

[0034] where, is the angular velocity of the fixed-displacement pump, in rad / s; is the angular velocity of the fixed-displacement motor, in rad / s; P h is the pressure difference between the inlet and outlet of the fixed-displacement pump, in Pa; B p is the damping coefficient of the fixed-displacement pump, in N / (m / s); J p is the moment of inertia of the fixed-displacement pump, in kg·m 2 ; J m is the moment of inertia of the fixed-displacement motor, in kg·m 2 ; D p is the displacement of the fixed-displacement pump, in m 3 / s; V is the total volume of the high-pressure chamber, in m 3 ; D m is the displacement of the fixed-displacement motor, in m 3 / s; C t is the total leakage coefficient C t = C tp + C tm ,in m 3 / (s·Pa); β e is the bulk modulus of the oil, with the unit of Pa; T v is the aerodynamic torque output by the wind turbine under a certain wind speed, with the unit of N·m; T L is the load torque of the fixed-displacement motor, with the unit of N·m.

[0035] Then, combining the neural network based on the RBF function and the nonlinear extended state observer, an intelligent speed control strategy for the pump-controlled hydraulic motor nonlinear system is obtained, which online observes the unknown nonlinear dynamics and external disturbances, and deals with the problem of unmatched disturbances, and observes and compensates the key parameters of the pump-controlled motor hydraulic load simulation system. Taking the speed of the fixed-displacement motor as the control output, initializing the state observation variables and the neural network weights, through the extended state observer of the RBF neural network, the time-varying variables of the system are identified, and the external disturbances and internal disturbances are observed.

[0036]

[0037] Among them, η j+1 is the state variable; is the error value of the state variable; is the bounded constant matrix of the ideal weight; is the RBFNN weight; is the new state variable error value; μ 1 is the parameter of the characteristic polynomial in Hurwitz; is the adjustable positive gain, i.e., the bandwidth of each ESO; η j is the state variable; is the error value of the nth-order new state variable; μ 2 is the parameter of the characteristic polynomial in Hurwitz; is the error value of the nth-order new state variable; u(α) is the saturation input; is the bounded constant matrix of the ideal weight; is the RBFNN weight; is the nth-order adjustable positive gain, i.e., the bandwidth of each ESO; η n is the nth-order new state variable.

[0038] Then, continuously update the neural network weight formula (1), through the approximation function formula (2), make the error continuously decrease, propose the virtual control law formula (3), through the second-order filtering function formula (4), and finally obtain the real speed control law formula (5). Combining the compensation control law formula (6) and the neural network to continuously learn and continuously revise the speed control law, and finally act on the system to achieve the control effect ultimately.

[0039]

[0040]

[0041] Among them, is a bounded constant matrix of ideal weights; is the weight of the RBFNN; is a non-linear function; φ l is a virtual control function; k l is the positive feedback gain; e l is the tracking error variable; is the error value of the n-th order new state variable; y d is the variable output value; z l is the error compensation variable; is the estimated error value of the n-th order new state variable; φ j,cc is the internal dynamics parameter; r fj is the adjustable parameter; φ j,c is the output signal of a single introduced filter; is the estimated bounded constant matrix of ideal weights; is the filter error value at time j; is the filter error value at time n; Δu = u(α) - α, that is, the difference between the saturated input and the actual input.

[0042] A grid-connected speed control system and method for an energy storage hydraulic wind turbine provided by the present invention. The ESO based on RBF-NN can accurately estimate the system state and accurately estimate external disturbances at the same time. It makes the grid-connected speed control more flexible, improves the robustness and adaptive performance of the system, and ensures the rapidity and reliability during the control process; the intelligent control method based on neural network can eliminate traditional wind speed sensors and flow sensors, making the system more flexible and saving equipment costs. In addition, it is different from traditional intelligent control algorithms in that it increases the real-time performance and effectiveness of the algorithm model operation results participating in the control, avoids the risk of wind farm data leakage, and saves the network transmission cost of data transmission. The hydraulic energy storage device can buffer the impact caused by voltage mutation and ensure the ability of the equipment to operate continuously without disconnecting from the grid; at the same time, the hydraulic energy storage device can adjust the energy input to the system in real time, coordinate the energy allocation from the source, avoid damage caused by excess energy, and make full use of the excess energy. It absorbs energy in the pump control condition and outputs energy in the motor condition.

[0043] The present invention has been described in detail above in combination with specific embodiments and exemplary examples, but these descriptions should not be construed as limiting the present invention. Those skilled in the art understand that without departing from the spirit and scope of the present invention, various equivalent substitutions, modifications or improvements can be made to the technical solutions and implementation manners of the present invention, and these all fall within the scope of the present invention. The protection scope of the present invention shall be subject to the appended claims.

Claims

1. A grid-connected speed control system for an energy storage hydraulic wind turbine generator set. It is characterized in that It includes a wind turbine device, a hydraulic transmission device, a hydraulic energy storage device and a grid-connected power generation device; the wind turbine device and the hydraulic transmission device, the hydraulic transmission device and the hydraulic energy storage device, and the hydraulic energy storage device and the grid-connected power generation device are coaxially rigidly connected; The wind turbine device comprises a wind speed predictor (1), a wind wheel (2) and a first transmission shaft (3); the wind wheel (2) is transmission-connected to the first transmission shaft (3), and the wind speed predictor (1) is located on a side of the wind wheel (2) away from the first transmission shaft (3); The hydraulic transmission device comprises a first speed torque sensor (4), a metering pump (5), a high-pressure pipeline (6), a first one-way valve (7), a second one-way valve (8), a first overflow valve (9), an oil replenishment pump (10), an oil replenishment tank (11), a safety valve (12), a flow controller (13), a speed controller (14), a variable motor (15), a second speed torque sensor (16), a low-pressure pipeline (24) and a power controller (25); The hydraulic energy storage device comprises a variable pump motor (17), an accumulator (18) and an energy storage system oil tank (19); The grid-connected power generation device comprises a generator (20), a grid-connected cabinet (21) and a power grid (22); The first rotational speed torque sensor (4) is arranged on the first transmission shaft (3); the main shaft of the fixed displacement pump (5) is in transmission connection with one end of the first transmission shaft (3) away from the wind turbine (2); the oil inlet of the fixed displacement pump (5) sucks oil from the oil replenishing tank (11) through the low-pressure pipeline (24), and the oil outlet discharges high-pressure oil through the high-pressure pipeline (6); the flow controller (13) is arranged on the high-pressure pipeline (6); the outlet end of the first check valve (7) is communicated with the high-pressure pipeline (6), and the inlet end is communicated with the inlet end of the second check valve (8); the outlet end of the second check valve (8) is communicated with the low-pressure pipeline (24); both ends of the first relief valve (9) are respectively connected with the oil outlet of the oil replenishing pump (10) and the oil replenishing tank (11); the oil outlet of the oil replenishing pump (10) is respectively connected with the inlet end of the first check valve (7) and the inlet end of the second check valve (8), and the oil inlet is connected with the oil replenishing tank (11); both ends of the safety valve (12) are respectively connected with the high-pressure pipeline (6) and the low-pressure pipeline (24); the input end of the speed controller (14) is respectively connected with the flow controller (13), the second rotational speed torque sensor (16) and the grid connection cabinet (21), and the output end is connected with the variable motor (15); the oil inlet of the variable motor (15) is connected with the high-pressure pipeline (6), and the oil outlet is connected with the low-pressure pipeline (24); the main shaft of the variable motor (15) is coaxially connected with the main shaft of the generator (20) through the second transmission shaft (26); the generator (20) generates electricity and inputs electric energy to the power grid (22); the grid connection cabinet (21) is installed between the generator (20) and the power grid (22); the second rotational speed torque sensor (16) is installed on the second transmission shaft (26); the variable pump motor (17) is connected with the energy storage system oil tank (19) and is connected with the accumulator (18) through the energy storage pipeline (23) so that the accumulator (18) stores and releases energy in different states; the input end of the power controller (25) is respectively connected with the wind speed predictor (1), the first rotational speed torque sensor (4), the second rotational speed torque sensor (16) and the grid connection cabinet (21), and the output end is connected with the variable pump motor (17); The control method of the grid-connected speed control system of the energy storage type hydraulic wind power generation set includes: When the energy storage hydraulic wind turbine is disturbed, the speed controller (14) collects the speed of the variable motor (15) through the second speed-torque sensor (16), the flow controller (13) collects the flow of the high-pressure pipeline (6), and the grid connection cabinet (21) collects the frequency and voltage of the power grid (22). Then the speed controller (14) outputs a control signal to the variable motor (15) to realize the swashplate angle control of the variable motor (15), change the displacement of the variable motor (15), so that the oil pressure of the high-pressure oil in the high-pressure pipeline (6) of the hydraulic transmission part also changes accordingly, thereby changing the speed of the fixed-displacement pump (5) and releasing the energy stored in the wind turbine; The power controller (25) collects the wind speed through the wind speed predictor (1), the first speed-torque sensor (4) collects the speed of the wind wheel (2) and outputs the impeller torque, the second speed-torque sensor (16) collects the torque of the generator (20), and the grid connection cabinet (21) collects the output power of the generator (20) and the grid voltage. Then the power controller (25) outputs a control signal to the variable pump-motor (17) of the hydraulic energy storage device to make the variable pump-motor (17) operate in the motor condition and input high-pressure oil into the accumulator (18). The power controller (25) increases the swashplate angle of the variable pump-motor (17) to quickly release the energy in the accumulator (18); When the disturbance is eliminated, the speed controller (14) plans the displacement of the variable motor (15), and the power controller (25) simultaneously plans the displacement action command of the variable pump-motor (17) of the hydraulic energy storage system, so that the variable pump-motor (17) stores and releases energy in the motor condition, adjusts the output power of the unit, and dynamically injects power into the power grid (22) to achieve the grid-side frequency response; The wind speed predictor (1) uses a neural network with RBF function to predict the wind speed. The grid connection speed control process: the flow controller (13) based on the neural network with RBF function and the nonlinear extended state observer, the specific process is as follows: First, analyze the influence of model uncertainty, parameter time-variation, and system external disturbance on the motor speed control system, and obtain the nonlinearity of the pump-controlled vane motor speed control system as follows: Wherein, is the angular velocity of the fixed-displacement pump, with the unit of rad / s; is the angular velocity of the fixed-displacement motor, with the unit of rad / s; P h is the pressure difference between the inlet and outlet of the fixed-displacement pump, with the unit of Pa; B p is the damping coefficient of the fixed-displacement pump, with the unit of N / (m / s); J p is the moment of inertia of the fixed-displacement pump, with the unit of kg·m 2 ; J m is the moment of inertia of the fixed-displacement motor, with the unit of kg·m 2 ; D p is the displacement of the fixed-displacement pump, with the unit of m 3 / s; V is the total volume of the high-pressure chamber, with the unit of m 3 ; D m is the displacement of the fixed-displacement motor, with the unit of m 3 / s; C t is the total leakage coefficient C t = C tp + C tm , with the unit of m 3 / (s·Pa); β e is the bulk modulus of elasticity of the oil, with the unit of Pa; T v is the aerodynamic torque output by the wind turbine under the action of a certain wind speed, with the unit of N·m; T L is the load torque of the fixed-displacement motor, with the unit of N·m; Then, combined with the neural network based on the RBF function and the nonlinear extended state observer, obtain the intelligent speed control strategy for the nonlinear system of the pump-controlled hydraulic motor, online observe the unknown nonlinear dynamics and external disturbances, and deal with the problem of unmatched disturbances, observe and compensate the key parameters of the pump-controlled motor hydraulic load simulation system, use the fixed-displacement motor speed as the control output, initialize the state observation quantity and the neural network weight, and identify the time-varying quantity of the system, observe the external disturbance and the internal disturbance through the extended state observer of the RBF neural network: Among them, η j+1 is a state variable; is the error value of the state variable; is a bounded constant matrix of the ideal weight; is the RBFNN weight; is the new state variable error value; μ 1 is the parameter of the characteristic polynomial in Hurwitz; is the adjustable positive gain, i.e., the bandwidth of each ESO; η j is a state variable; is the n-th order new state variable error value; μ 2 is the parameter of the characteristic polynomial in Hurwitz; is the n-th order new state variable error value; u(α) is the saturation input; is a bounded constant matrix of the ideal weight; is the RBFNN weight; is the n-th order adjustable positive gain, i.e., the bandwidth of each ESO; η n is the n-th order new state variable; Then continuously update the neural network weight formula (1), make the error continuously decrease through the approximation function formula (2), propose the virtual control law formula (3), and finally obtain the real speed control law formula (5) through the second-order filter function formula (4). Combine the compensation control law formula (6) and the neural network to continuously learn and continuously revise the speed control law, and finally act on the system to achieve the control effect: wherein, is a bounded constant matrix of ideal weights; is the weight of the RBFNN; is a non - linear function; φ l is a virtual control function; k l is a positive feedback gain; e l is a tracking error variable; is the error value of the n - th order new state variable; y d is the variable output value; z l is an error compensation variable; is the estimated error value of the n - th order new state variable; φ j,cc is an internal dynamics parameter; r fj is an adjustable parameter; φ j,c is the output signal of a single introduced filter; is an estimated bounded constant matrix of ideal weights; is the filtering error value at the j - th moment; is the filtering error value at the n - th moment; Δu = u(α)-α, that is, the difference between the saturated input and the actual input.

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