Wind power plant fan control and direct current transmission networking sending parameter optimization method and system

Abstract

The invention provides a wind power plant fan control and direct current transmission networking sending parameter optimization method and system. The method comprises the following steps: acquiring a standard voltage control parameter and a standard current control parameter of a fan, and a standard voltage control parameter and a standard current control parameter of a high-voltage flexible direct current transmission system; substituting the standard voltage control parameter and the standard current control parameter of the fan and the standard voltage control parameter and the standard current control parameter of the high-voltage flexible direct-current power transmission system into a pre-constructed grid-connected optimization model, and performing optimization solution on the grid-connected optimization model by using a particle swarm optimization algorithm, obtaining a voltage control parameter reference value and a current control parameter reference value of the fan and a voltage control parameter reference value and a current control parameter reference value of the high-voltage flexible direct-current power transmission system; and optimizing the reference value to obtain the control parameter. According to the technical scheme provided by the invention, the minimization of power transmission loss, the maximization of power and the stability of voltage are realized.

Description

Technical Field

[0001] The present application relates to the technical field of wind power networking, and in particular to a method and system for optimizing wind turbine control and DC power transmission networking transmission parameters in a wind farm. Background Art

[0002] With the continuous growth of global energy demand, the development and application of new energy technologies have become an important way to solve energy problems. Wind power generation, as a clean and renewable energy source, has been widely used around the world. However, the randomness and volatility of wind energy have brought challenges to the stable operation of the power grid. In order to improve the utilization efficiency of large-scale wind energy and the stability of the power grid, high-voltage direct current transmission technology is frequently used in wind power grid-connected systems. At present, high-voltage direct current transmission technology is mainly realized through rectifiers, inverters and direct current transmission lines. The rectifier converts alternating current into direct current, the inverter converts direct current into alternating current, and the direct current transmission line is used to transmit electric energy over long distances. However, there are some problems with the traditional direct current transmission system, such as large transmission loss and poor voltage stability. In order to improve transmission efficiency and voltage stability, high-voltage flexible direct current transmission technology has been proposed and has been widely studied and applied.

[0003] Since high-voltage flexible direct current transmission technology can achieve independent regulation of active and reactive power by adjusting the control parameters of rectifiers and inverters, it can improve the operating efficiency and voltage stability of the transmission system. However, the application of high-voltage flexible direct current transmission technology in wind power grid connection still faces some challenges, such as the low accuracy of wind turbine control strategy and system coordination, system target optimization, etc., which leads to large transmission losses, inability to maximize power, and poor voltage stability. Therefore, it is urgent to propose a solution that can reduce transmission losses, improve power optimization output and voltage stability. Summary of the invention

[0004] The present application provides a method and system for optimizing wind farm wind turbine control and DC transmission network transmission parameters, so as to at least solve the technical problems of large transmission loss, inability to maximize power and poor voltage stability.

[0005] The first embodiment of the present application provides a method for optimizing wind farm wind turbine control and DC transmission network transmission parameters, the method comprising:

[0006] Obtain technical parameters of the wind turbines in the current wind farm and technical parameters of the high-voltage flexible direct current transmission system, and obtain standard voltage control parameters and standard current control parameters of the wind turbines and standard voltage control parameters and standard current control parameters of the high-voltage flexible direct current transmission system based on the technical parameters of the wind turbines in the current wind farm and the technical parameters of the high-voltage flexible direct current transmission system respectively;

[0007] Substituting the standard voltage control parameters and standard current control parameters of the wind turbine and the standard voltage control parameters and standard current control parameters of the high-voltage flexible direct current transmission system into a pre-built grid-connected optimization model, and optimizing and solving the grid-connected optimization model using a particle swarm optimization algorithm, to obtain reference values ​​of the voltage control parameters and current control parameters of the wind turbine and reference values ​​of the voltage control parameters and current control parameters of the high-voltage flexible direct current transmission system;

[0008] The voltage control parameter reference value and the current control parameter reference value of the wind turbine are used as the optimized voltage control parameter and the optimized current control parameter of the wind turbine, and the voltage control parameter reference value and the current control parameter reference value of the high-voltage flexible direct current transmission system are used as the optimized voltage control parameter and the optimized current control parameter of the high-voltage flexible direct current transmission system.

[0009] Preferably, the technical parameters of the wind turbine include: wind turbine type, capacity, grid-connected voltage level;

[0010] The technical parameters of the high-voltage flexible direct current transmission system include: transmission distance, transmission capacity, and voltage level.

[0011] Furthermore, the construction process of the grid-connected optimization model includes:

[0012] Construct the objective function with the maximum comprehensive index value as the goal;

[0013] A grid-connected optimization model is constructed with wind turbine control constraints, pitch angle control constraints, generator control constraints, rectifier control constraints, inverter control constraints, current loop control constraints, current constraints, DC transmission line protection constraints, voltage loop control constraints, and voltage fluctuation constraints as constraints, and combined with the objective function.

[0014] Furthermore, the objective function is calculated as follows:

[0015] maxF=α·f Efficiency +β·f Vstab +γ·[1-f Loss ]

[0016] In the formula, F is the comprehensive index value, f Efficiency is the efficiency index value, f Vstab is the voltage stability index value, f Loss is the line loss index value, α is the weight of the efficiency index, β is the weight of the voltage stability index, and γ is the weight of the line loss index, where α+β+γ=1.

[0017] Furthermore, the calculation formula of the efficiency index value is as follows:

[0018] f Efficiency =Pout / Pin

[0019] In the formula, Pout is the fan output power, Pin is the fan input power;

[0020] The calculation formula of the voltage stability index value is as follows:

[0021]

[0022] Where V dc1 is the DC input voltage, V dc2 is the DC side output voltage, V rated is the rated voltage of the DC transmission system;

[0023] The calculation formula of the line loss index value is as follows:

[0024]

[0025] Where R is the line resistance, I dc is a direct current.

[0026] Furthermore, the calculation formula of the fan control constraint is as follows:

[0027]

[0028] Where v is the wind speed, k is the shape parameter, describing the shape of the wind speed distribution, and λ is the scale parameter, which is related to the average wind speed;

[0029] The calculation formula of the pitch angle control constraint is as follows:

[0030]

[0031] Where δ is the pitch angle, K p is the ratio of the PID controller, e(t) is the error signal, K i is the integral of the PID controller, K d is the differential gain of the PID controller;

[0032] The calculation formula of the generator control constraint is as follows:

[0033]

[0034] Where, T e is the electromagnetic torque, p is the number of pole pairs, L m is the mutual inductance, L l is the leakage inductance, i qr is the quadrature axis component of the rotor current, i qd is the direct axis component of the rotor current, J is the moment of inertia, ωm is the mechanical angular velocity, T L is the load torque;

[0035] The calculation formula of the rectifier control constraint is as follows:

[0036]

[0037] In the formula, i a is the AC side current, L is the filter inductance, υ dc is the DC side voltage, υ a is the AC side voltage of the rectifier, R is the resistance;

[0038] The calculation formula of the inverter control constraint is as follows:

[0039]

[0040] In the formula, i b is the AC side current, υ ref is the reference voltage, υ b is the AC side voltage of the inverter;

[0041] The calculation formula of the current loop control constraint is as follows:

[0042]

[0043] In the formula, id * To control the target current, i d is the measured current value;

[0044] The current constraint is calculated as follows:

[0045]

[0046] In the formula, i max is the system current value, is the system current extreme value;

[0047] The calculation formula of the DC transmission line protection constraint is as follows:

[0048]

[0049] The voltage loop control constraint is calculated as follows:

[0050]

[0051] In the formula, To control the target voltage, K vp is the control voltage proportional gain coefficient, v d is the measured voltage value, K vi is the control voltage integral gain coefficient;

[0052] The calculation formula of the voltage fluctuation constraint is as follows:

[0053]

[0054] Where Δv is the measured voltage fluctuation value of the system, K f is the voltage fluctuation coefficient.

[0055] Preferably, the method further comprises:

[0056] Based on the technical parameters, voltage control parameter reference values, current control parameter reference values ​​of the wind turbines in the current wind farm and the technical parameters, voltage control parameter reference values, current control parameter reference values ​​of the high-voltage flexible DC transmission system, simulation is performed to obtain simulation experimental results;

[0057] When the simulation experiment result is greater than a preset deviation value, the constraint conditions of the grid-connected optimization model are adjusted.

[0058] The second embodiment of the present application provides a wind farm wind turbine control and DC transmission network transmission parameter optimization system, including:

[0059] An acquisition module is used to acquire the technical parameters of the wind turbines in the current wind farm and the technical parameters of the high-voltage flexible direct current transmission system, and acquire the standard voltage control parameters and standard current control parameters of the wind turbines and the standard voltage control parameters and standard current control parameters of the high-voltage flexible direct current transmission system based on the technical parameters of the wind turbines in the current wind farm and the technical parameters of the high-voltage flexible direct current transmission system respectively;

[0060] An optimization solution module, used for substituting the standard voltage control parameters and standard current control parameters of the wind turbine and the standard voltage control parameters and standard current control parameters of the high-voltage flexible direct current transmission system into a pre-built grid-connected optimization model, and optimizing and solving the grid-connected optimization model using a particle swarm optimization algorithm to obtain reference values ​​of voltage control parameters and current control parameters of the wind turbine and reference values ​​of voltage control parameters and current control parameters of the high-voltage flexible direct current transmission system;

[0061] A determination module is used to use the voltage control parameter reference value and the current control parameter reference value of the wind turbine as the optimized voltage control parameter and the optimized current control parameter of the wind turbine, and to use the voltage control parameter reference value and the current control parameter reference value of the high-voltage flexible direct current transmission system as the optimized voltage control parameter and the optimized current control parameter of the high-voltage flexible direct current transmission system.

[0062] The third aspect of the present application provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method described in the first aspect is implemented.

[0063] A fourth aspect of the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described in the first aspect of the present application.

[0064] The technical solution provided by the embodiments of the present application brings at least the following beneficial effects:

[0065] The present application proposes a method and system for optimizing wind farm wind turbine control and direct current transmission network transmission parameters. The method includes: obtaining the technical parameters of the current wind farm wind turbine and the technical parameters of the high-voltage flexible direct current transmission system, and obtaining the standard voltage control parameters and standard current control parameters of the wind turbine, and the standard voltage control parameters and standard current control parameters of the high-voltage flexible direct current transmission system based on the technical parameters of the current wind farm wind turbine and the technical parameters of the high-voltage flexible direct current transmission system respectively; substituting the standard voltage control parameters and standard current control parameters of the wind turbine, and the standard voltage control parameters and standard current control parameters of the high-voltage flexible direct current transmission system into a pre-built grid-connected optimization model In the embodiment, the particle swarm optimization algorithm is used to optimize and solve the grid-connected optimization model, and the voltage control parameter reference value and current control parameter reference value of the wind turbine are obtained, and the voltage control parameter reference value and current control parameter reference value of the high-voltage flexible DC power transmission system are obtained; the voltage control parameter reference value and current control parameter reference value of the wind turbine are used as the optimized voltage control parameters of the wind turbine and the optimized current control parameters of the wind turbine, and the voltage control parameter reference value and current control parameter reference value of the high-voltage flexible DC power transmission system are used as the optimized voltage control parameters of the high-voltage flexible DC power transmission system and the optimized current control parameters of the high-voltage flexible DC power transmission system. The technical solution proposed in this application finds the optimal control parameter combination through the particle swarm optimization algorithm, realizes the minimization of transmission loss and the stabilization of voltage, which is of great significance for the grid connection of new energy and long-distance power transmission.

[0066] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0068] Figure 1A flow chart of a method for optimizing wind farm wind turbine control and DC transmission network transmission parameters according to an embodiment of the present application;

[0069] Figure 2 A first structural diagram of a wind farm wind turbine control and DC transmission network transmission parameter optimization system provided according to an embodiment of the present application;

[0070] Figure 3 A second structural diagram of a wind farm wind turbine control and DC transmission networking transmission parameter optimization system provided according to an embodiment of the present application. DETAILED DESCRIPTION

[0071] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0072] The present application proposes a method and system for optimizing wind farm wind turbine control and direct current transmission network transmission parameters, the method comprising: obtaining the technical parameters of the current wind farm wind turbine and the technical parameters of the high-voltage flexible direct current transmission system, and obtaining the standard voltage control parameters and standard current control parameters of the wind turbine, and the standard voltage control parameters and standard current control parameters of the high-voltage flexible direct current transmission system based on the technical parameters of the current wind farm wind turbine and the technical parameters of the high-voltage flexible direct current transmission system respectively; substituting the standard voltage control parameters and standard current control parameters of the wind turbine, and the standard voltage control parameters and standard current control parameters of the high-voltage flexible direct current transmission system into a pre-built grid-connected optimization model In the embodiment, the particle swarm optimization algorithm is used to optimize and solve the grid-connected optimization model, and the voltage control parameter reference value and current control parameter reference value of the wind turbine are obtained, and the voltage control parameter reference value and current control parameter reference value of the high-voltage flexible DC power transmission system are obtained; the voltage control parameter reference value and current control parameter reference value of the wind turbine are used as the optimized voltage control parameters of the wind turbine and the optimized current control parameters of the wind turbine, and the voltage control parameter reference value and current control parameter reference value of the high-voltage flexible DC power transmission system are used as the optimized voltage control parameters of the high-voltage flexible DC power transmission system and the optimized current control parameters of the high-voltage flexible DC power transmission system. The technical solution proposed in this application finds the optimal control parameter combination through the particle swarm optimization algorithm, realizes the minimization of transmission loss and the stabilization of voltage, which is of great significance for the grid connection of new energy and long-distance power transmission.

[0073] The following describes a method and system for wind farm wind turbine control and DC transmission network transmission parameter optimization according to an embodiment of the present application with reference to the accompanying drawings.

[0074] Embodiment 1

[0075] Figure 1 A flow chart of a method for optimizing wind farm wind turbine control and DC transmission network transmission parameters according to an embodiment of the present application is provided. Figure 1 As shown, the method includes:

[0076] Step 1: Obtain technical parameters of the wind turbines in the current wind farm and technical parameters of the high-voltage flexible direct current transmission system, and obtain standard voltage control parameters and standard current control parameters of the wind turbines and standard voltage control parameters and standard current control parameters of the high-voltage flexible direct current transmission system based on the technical parameters of the wind turbines in the current wind farm and the technical parameters of the high-voltage flexible direct current transmission system respectively;

[0077] In the disclosed embodiment, the technical parameters of the wind turbine include: wind turbine type, capacity, grid-connected voltage level;

[0078] The technical parameters of the high-voltage flexible direct current transmission system include: transmission distance, transmission capacity, and voltage level.

[0079] It should be noted that a demand analysis should be conducted first to determine the technical requirements for wind turbine grid connection, including wind turbine type, capacity, and grid voltage level, and to analyze the technical parameters of the high-voltage DC flexible transmission system, such as transmission distance, transmission capacity, and voltage level. At the same time, a comprehensive optimization problem, namely the objective function, should be defined.

[0080] For example, for the type of wind turbine, we choose the horizontal axis wind turbine; for the capacity, we assume that we choose a 5MW wind turbine; the grid voltage level is set to 35kV. At the same time, we analyze the technical parameters of the high-voltage flexible DC transmission system, such as the transmission distance is set to 200 kilometers, the transmission capacity is 200MW, and the voltage level is ±330kV.

[0081] Step 2: Substitute the standard voltage control parameters and standard current control parameters of the wind turbine and the standard voltage control parameters and standard current control parameters of the high-voltage flexible DC power transmission system into a pre-built grid-connected optimization model, and use a particle swarm optimization algorithm to optimize and solve the grid-connected optimization model to obtain reference values ​​of voltage control parameters and current control parameters of the wind turbine and reference values ​​of voltage control parameters and current control parameters of the high-voltage flexible DC power transmission system;

[0082] In the embodiment of the present disclosure, the construction process of the grid connection optimization model includes:

[0083] Construct the objective function with the maximum comprehensive index value as the goal;

[0084] A grid-connected optimization model is constructed with wind turbine control constraints, pitch angle control constraints, generator control constraints, rectifier control constraints, inverter control constraints, current loop control constraints, current constraints, DC transmission line protection constraints, voltage loop control constraints, and voltage fluctuation constraints as constraints, and combined with the objective function.

[0085] Furthermore, the objective function is calculated as follows:

[0086] maxF=α·f Efficiency +β·f Vstab +γ·[1-f Loss ]

[0087] In the formula, F is the comprehensive index value, f Efficiency is the efficiency index value, f Vstab is the voltage stability index value, f Loss is the line loss index value, α is the weight of the efficiency index, β is the weight of the voltage stability index, and γ is the weight of the line loss index, where α+β+γ=1.

[0088] Furthermore, the calculation formula of the efficiency index value is as follows:

[0089] f Efficiency =Pout / Pin

[0090] In the formula, Pout is the fan output power, Pin is the fan input power;

[0091] The calculation formula of the voltage stability index value is as follows:

[0092]

[0093] Where V dc1 is the DC input voltage, V dc2 is the DC side output voltage, V rated is the rated voltage of the DC transmission system;

[0094] The calculation formula of the line loss index value is as follows:

[0095]

[0096] Where R is the line resistance, I dc is a direct current.

[0097] Furthermore, the calculation formula of the fan control constraint is as follows:

[0098]

[0099] Where v is the wind speed, k is the shape parameter, describing the shape of the wind speed distribution, and λ is the scale parameter, which is related to the average wind speed;

[0100] The calculation formula of the pitch angle control constraint is as follows:

[0101]

[0102] Where δ is the pitch angle, K p is the ratio of the PID controller, e(t) is the error signal, K i is the integral of the PID controller, K d is the differential gain of the PID controller;

[0103] The calculation formula of the generator control constraint is as follows:

[0104]

[0105] Where, T e is the electromagnetic torque, p is the number of pole pairs, L m is the mutual inductance, L l is the leakage inductance, i qr is the quadrature axis component of the rotor current, i qd is the direct axis component of the rotor current, J is the moment of inertia, ω m is the mechanical angular velocity, T L is the load torque;

[0106] The calculation formula of the rectifier control constraint is as follows:

[0107]

[0108] In the formula, i a is the AC side current, L is the filter inductance, υ dc is the DC side voltage, υ a is the AC side voltage of the rectifier, R is the resistance;

[0109] The calculation formula of the inverter control constraint is as follows:

[0110]

[0111] In the formula, i b is the AC side current, υ ref is the reference voltage, υ b is the AC side voltage of the inverter;

[0112] The calculation formula of the current loop control constraint is as follows:

[0113]

[0114] In the formula, id * To control the target current, i d is the measured current value;

[0115] The current constraint is calculated as follows:

[0116]

[0117] In the formula, i max is the system current value, is the system current extreme value;

[0118] The calculation formula of the DC transmission line protection constraint is as follows:

[0119]

[0120] The calculation formula of the voltage loop control constraint is as follows:

[0121]

[0122] In the formula, To control the target voltage, K vp is the control voltage proportional gain coefficient, v d is the measured voltage value, K vi is the control voltage integral gain coefficient;

[0123] The calculation formula of the voltage fluctuation constraint is as follows:

[0124]

[0125] Where Δv is the measured voltage fluctuation value of the system, K f is the voltage fluctuation coefficient.

[0126] It should be noted that the fan control constraint is obtained based on the fan mathematical model and the preset fan control strategy, and the fan mathematical model uses Weibull distribution to describe the probability density function of wind speed;

[0127] The pitch angle control constraint is obtained based on a pitch angle control model and a preset pitch angle control strategy, and the pitch angle control model is controlled using a PID control strategy;

[0128] The generator control constraints are obtained based on a simplified induction motor model and a preset generator control strategy;

[0129] The rectifier control constraint is obtained based on a voltage source converter model and a preset rectifier control strategy;

[0130] The inverter control constraint is obtained based on the VSC model and a preset inverter control strategy;

[0131] The DC transmission line protection constraint is obtained based on a DC transmission line model and a preset DC transmission line protection strategy.

[0132] It should be noted that, for example, the wind speed change within the next 10 minutes is predicted. Then, the pitch angle control strategy, i.e., the pitch angle control constraint, is designed, and the pitch angle is adjusted by the PID controller to achieve maximum wind energy capture. For example, when the wind speed changes, the pitch angle is adjusted to maintain the optimal tip speed ratio. Finally, the generator control strategy, i.e., the generator control constraint, is designed, and the quality of the output power is guaranteed by methods such as vector control, such as setting the THD of the output voltage to less than 5%.

[0133] First, the rectifier control strategy, i.e., the rectifier control constraint, is designed. The active and reactive power are adjusted independently through the PI controller. Assume that the active power set point is 100MW and the reactive power set point is 0MVar. Secondly, the inverter control strategy, i.e., the inverter control constraint, is designed. Through the current inner loop and voltage outer loop control, the power quality on the grid side is guaranteed, such as setting the THD of the grid current to less than 3%. Finally, the DC transmission line protection strategy, i.e., the DC transmission line protection constraint, is designed, including overvoltage and overcurrent protection, to ensure the safe operation of the system under abnormal conditions, such as setting the overvoltage protection threshold to 350kV.

[0134] It should be noted that the particle swarm optimization (PSO) algorithm is selected to optimize the wind turbine control parameters and the high-voltage flexible DC transmission system control parameters. When updating the speed and position of the particles, it is necessary to ensure that the movement direction of the particles can simultaneously optimize the efficiency, voltage stability and line loss.

[0135] The optimization and solution of the grid connection optimization model by using the particle swarm optimization algorithm specifically includes:

[0136] Step F1: Define the optimization problem, i.e. the objective function, and the calculation formula is:

[0137] maxF=α·f Efficiency +β·f Vstab +γ·[1-f Loss ];

[0138] Among them, α, β, and γ are used to balance the importance of different indicators;

[0139] Step F2: Initialize the particle swarm,

[0140] xi=[Kp,i,Ki,i,Kd,i,Kvp,vd,Kvi,vd];

[0141] Where i is the particle number,

[0142] Kp,i, Ki,i, Kd,i are the wind turbine PID control parameters, Kvp,vd, Kvi,vd are the reference voltage parameters of the HVDC transmission system;

[0143] Step F3: Evaluate particle fitness. For each particle, calculate the objective function value and check whether the constraint conditions are met. If the constraint conditions are not met, a penalty function can be used to adjust the fitness value. The calculation formula is:

[0144]

[0145] Where gj(xi) is the jth constraint and penalty is the penalty function;

[0146] Step F4: Update individual and global optimal solutions. Each particle updates its own historical optimal solution pi and global optimal solution g. The update formula is:

[0147]

[0148] Step F5: Update the particle position and velocity. The formula for updating the particle velocity and position is:

[0149] u i，d (t+1)=w·v i，d (t)+c1·r1·(p i，d (t)-x i，d (t))+c2·r2·(g d (t)-x i，d (t))

[0150] x i (t+1)=x i (t)+v i (t+1)

[0151] Where: vi,d(t) is the velocity of particle i in dimension d; w is the inertia weight; c1 and c2 are learning factors; r1 and r2 are random numbers in the range [0,1]; pi,d(t) is the value of the historical optimal solution of particle i in dimension d; gd(t) is the value of the global optimal solution in dimension d.

[0152] Step F6: Iteration and termination conditions, repeating steps F3 to F5 until the maximum number of iterations is reached to end the entire process.

[0153] Step 3: Use the voltage control parameter reference value and the current control parameter reference value of the wind turbine as the optimized voltage control parameter and the optimized current control parameter of the wind turbine, and use the voltage control parameter reference value and the current control parameter reference value of the high-voltage flexible direct current transmission system as the optimized voltage control parameter and the optimized current control parameter of the high-voltage flexible direct current transmission system.

[0154] In an embodiment of the present disclosure, the method further includes:

[0155] Based on the technical parameters, voltage control parameter reference values, current control parameter reference values ​​of the wind turbines in the current wind farm and the technical parameters, voltage control parameter reference values, current control parameter reference values ​​of the high-voltage flexible DC transmission system, simulation is performed to obtain simulation experimental results;

[0156] When the simulation experiment result is greater than a preset deviation value, the constraint conditions of the grid-connected optimization model are adjusted.

[0157] It should be noted that the simulation software MATLAB / Simulink was used to build the grid-connected optimization model of wind turbine control and high-voltage flexible DC transmission;

[0158] Tests are conducted at actual wind turbine grid-connected sites to verify the feasibility of the optimization method. Based on the field test results, the control strategy, i.e., the constraints, are fine-tuned to adapt to the actual operating environment. The operating status of the grid-connected system is continuously monitored to ensure long-term stability of the optimization effect.

[0159] Specifically, in the simulation environment, the model is set according to the actual parameters, such as the mechanical parameters and electrical parameters of the wind turbine, and the line parameters of the DC transmission system. The simulation is run to observe the dynamic response of the system under different working conditions and verify the effectiveness of the control strategy. For example, a step change in wind speed is simulated to observe whether the response of the wind turbine and the transmission system meets expectations.

[0160] Conduct tests at actual wind turbine grid-connected sites to verify the feasibility of the optimization method. Fine-tune the control strategy based on the field test results. For example, if a deviation is found in the actual wind speed forecast, adjust the parameters of the forecast module. Continuously monitor the grid-connected system operation status to ensure the long-term stability of the optimization effect, such as regularly recording key parameters such as wind turbine output power and DC transmission line voltage, analyzing the changing trend of system performance, and adjusting constraints as needed.

[0161] In summary, the present embodiment proposes a method for optimizing wind farm wind turbine control and DC transmission network transmission parameters. Through the particle swarm optimization algorithm, the optimal control parameter combination is found, and the transmission loss is minimized and the voltage is stabilized. This is of great significance for new energy grid connection and long-distance power transmission.

[0162] Embodiment 2

[0163] Figure 2 The structure diagram of a wind farm wind turbine control and DC transmission network transmission parameter optimization system provided according to one embodiment of the present application is as follows: Figure 2 As shown, the system comprises:

[0164] The acquisition module 100 is used to acquire the technical parameters of the wind turbines in the current wind farm and the technical parameters of the high-voltage flexible direct current transmission system, and acquire the standard voltage control parameters and standard current control parameters of the wind turbines and the standard voltage control parameters and standard current control parameters of the high-voltage flexible direct current transmission system based on the technical parameters of the wind turbines in the current wind farm and the technical parameters of the high-voltage flexible direct current transmission system respectively;

[0165] The technical parameters of the wind turbine include: wind turbine type, capacity, grid-connected voltage level;

[0166] The technical parameters of the high-voltage flexible direct current transmission system include: transmission distance, transmission capacity, and voltage level.

[0167] The optimization solution module 200 is used to substitute the standard voltage control parameters and standard current control parameters of the wind turbine and the standard voltage control parameters and standard current control parameters of the high-voltage flexible direct current transmission system into a pre-built grid-connected optimization model, and optimize and solve the grid-connected optimization model using a particle swarm optimization algorithm to obtain reference values ​​of voltage control parameters and current control parameters of the wind turbine and reference values ​​of voltage control parameters and current control parameters of the high-voltage flexible direct current transmission system;

[0168] It should be noted that the construction process of the grid-connected optimization model includes:

[0169] Construct the objective function with the maximum comprehensive index value as the goal;

[0170] A grid-connected optimization model is constructed with wind turbine control constraints, pitch angle control constraints, generator control constraints, rectifier control constraints, inverter control constraints, current loop control constraints, current constraints, DC transmission line protection constraints, voltage loop control constraints, and voltage fluctuation constraints as constraints, and combined with the objective function.

[0171] The objective function is calculated as follows:

[0172] max F=α·f Efficiency +β·f Vstab +γ·[1-f Loss ]

[0173] In the formula, F is the comprehensive index value, f Efficiency is the efficiency index value, f Vstab is the voltage stability index value, f Loss is the line loss index value, α is the weight of the efficiency index, β is the weight of the voltage stability index, and γ is the weight of the line loss index, where α+β+γ=1.

[0174] The calculation formula of the efficiency index value is as follows:

[0175] f Efficiency =Pout / Pin

[0176] In the formula, Pout is the fan output power, Pin is the fan input power;

[0177] The calculation formula of the voltage stability index value is as follows:

[0178]

[0179] Where V dc1 is the DC input voltage, V dc2 is the DC side output voltage, V rated is the rated voltage of the DC transmission system;

[0180] The calculation formula of the line loss index value is as follows:

[0181]

[0182] Where R is the line resistance, I dc is a direct current.

[0183] The calculation formula of the fan control constraint is as follows:

[0184]

[0185] Where v is the wind speed, k is the shape parameter, describing the shape of the wind speed distribution, and λ is the scale parameter, which is related to the average wind speed;

[0186] The calculation formula of the pitch angle control constraint is as follows:

[0187]

[0188] Where δ is the pitch angle, K p is the ratio of the PID controller, e(t) is the error signal, K i is the integral of the PID controller, K d is the differential gain of the PID controller;

[0189] The calculation formula of the generator control constraint is as follows:

[0190]

[0191] Where, T e is the electromagnetic torque, p is the number of pole pairs, L m is the mutual inductance, L l is the leakage inductance, i qr is the quadrature axis component of the rotor current, i qd is the direct axis component of the rotor current, J is the moment of inertia, ω mis the mechanical angular velocity, T L is the load torque;

[0192] The calculation formula of the rectifier control constraint is as follows:

[0193]

[0194] In the formula, i a is the AC side current, L is the filter inductance, υ dc is the DC side voltage, υ a is the AC side voltage of the rectifier, R is the resistance;

[0195] The calculation formula of the inverter control constraint is as follows:

[0196]

[0197] In the formula, i b is the AC side current, υ ref is the reference voltage, υ b is the AC side voltage of the inverter;

[0198] The calculation formula of the current loop control constraint is as follows:

[0199]

[0200] In the formula, id * To control the target current, i d is the measured current value;

[0201] The current constraint is calculated as follows:

[0202]

[0203] In the formula, i max is the system current value, is the system current extreme value;

[0204] The calculation formula of the DC transmission line protection constraint is as follows:

[0205]

[0206] The voltage loop control constraint is calculated as follows:

[0207]

[0208] In the formula, To control the target voltage, K vp is the control voltage proportional gain coefficient, v d is the measured voltage value, K vi is the control voltage integral gain coefficient;

[0209] The calculation formula of the voltage fluctuation constraint is as follows:

[0210]

[0211] Where Δv is the measured voltage fluctuation value of the system, K f is the voltage fluctuation coefficient.

[0212] The determination module 300 is used to use the voltage control parameter reference value and the current control parameter reference value of the wind turbine as the optimized voltage control parameter and the optimized current control parameter of the wind turbine, and to use the voltage control parameter reference value and the current control parameter reference value of the high-voltage flexible direct current transmission system as the optimized voltage control parameter and the optimized current control parameter of the high-voltage flexible direct current transmission system.

[0213] In the embodiments of the present disclosure, Figure 3 As shown, the system further includes: a simulation module 400;

[0214] The simulation module 400 is used for:

[0215] Based on the technical parameters, voltage control parameter reference values, current control parameter reference values ​​of the wind turbines in the current wind farm and the technical parameters, voltage control parameter reference values, current control parameter reference values ​​of the high-voltage flexible DC transmission system, simulation is performed to obtain simulation experimental results;

[0216] When the simulation experiment result is greater than a preset deviation value, the constraint conditions of the grid-connected optimization model are adjusted.

[0217] In summary, the wind farm wind turbine control and DC transmission network transmission parameter optimization system proposed in this embodiment finds the optimal control parameter combination through the particle swarm optimization algorithm, realizes the minimization of transmission loss and voltage stability, which is of great significance for new energy grid connection and long-distance power transmission.

[0218] Embodiment 3

[0219] In order to implement the above embodiments, the present disclosure further proposes an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method described in Embodiment 1 is implemented.

[0220] Embodiment 4

[0221] In order to implement the above embodiments, the present disclosure further proposes a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the method described in the first embodiment is implemented.

[0222] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" 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 representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0223] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0224] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for optimizing wind farm wind turbine control and DC transmission network transmission parameters, characterized in that: The method comprises: Obtain technical parameters of the wind turbines in the current wind farm and technical parameters of the high-voltage flexible direct current transmission system, and obtain standard voltage control parameters and standard current control parameters of the wind turbines and standard voltage control parameters and standard current control parameters of the high-voltage flexible direct current transmission system based on the technical parameters of the wind turbines in the current wind farm and the technical parameters of the high-voltage flexible direct current transmission system respectively; Substituting the standard voltage control parameters and standard current control parameters of the wind turbine and the standard voltage control parameters and standard current control parameters of the high-voltage flexible direct current transmission system into a pre-built grid-connected optimization model, and optimizing and solving the grid-connected optimization model using a particle swarm optimization algorithm, to obtain reference values ​​of the voltage control parameters and current control parameters of the wind turbine and reference values ​​of the voltage control parameters and current control parameters of the high-voltage flexible direct current transmission system; The voltage control parameter reference value and the current control parameter reference value of the wind turbine are used as the optimized voltage control parameter and the optimized current control parameter of the wind turbine, and the voltage control parameter reference value and the current control parameter reference value of the high-voltage flexible direct current transmission system are used as the optimized voltage control parameter and the optimized current control parameter of the high-voltage flexible direct current transmission system.

2. The method according to claim 1, characterized in that The technical parameters of the wind turbine include: wind turbine type, capacity, grid-connected voltage level; The technical parameters of the high-voltage flexible direct current transmission system include: transmission distance, transmission capacity, and voltage level.

3. The method according to claim 2, characterized in that The construction process of the grid-connected optimization model includes: Construct the objective function with the maximum comprehensive index value as the goal; A grid-connected optimization model is constructed with wind turbine control constraints, pitch angle control constraints, generator control constraints, rectifier control constraints, inverter control constraints, current loop control constraints, current constraints, DC transmission line protection constraints, voltage loop control constraints, and voltage fluctuation constraints as constraints, and combined with the objective function.

4. The method according to claim 3, characterized in that The objective function is calculated as follows: maxF=α·f Efficiency +β·f Vstab +γ·[1-f Loss ] In the formula, F is the comprehensive index value, f Efficiency is the efficiency index value, f Vstab is the voltage stability index value, f Loss is the line loss index value, α is the weight of the efficiency index, β is the weight of the voltage stability index, and γ is the weight of the line loss index, where α+β+γ=1.

5. The method according to claim 4, characterized in that The calculation formula of the efficiency index value is as follows: f Efficiency =Pout / Pin In the formula, Pout is the fan output power, Pin is the fan input power; The calculation formula of the voltage stability index value is as follows: Where V dc1 is the DC input voltage, V dc2 is the DC side output voltage, V rated is the rated voltage of the DC transmission system; The calculation formula of the line loss index value is as follows: Where R is the line resistance, I dc is a direct current.

6. The method according to claim 5, characterized in that The calculation formula of the fan control constraint is as follows: Where v is the wind speed, k is the shape parameter, describing the shape of the wind speed distribution, and λ is the scale parameter, which is related to the average wind speed; The calculation formula of the pitch angle control constraint is as follows: Where δ is the pitch angle, K p is the ratio of the PID controller, e(t) is the error signal, K i is the integral of the PID controller, K d is the differential gain of the PID controller; The calculation formula of the generator control constraint is as follows: Where, T e is the electromagnetic torque, p is the number of pole pairs, L m is the mutual inductance, L l is the leakage inductance, i qr is the quadrature axis component of the rotor current, i qd is the direct axis component of the rotor current, J is the moment of inertia, ω m is the mechanical angular velocity, T L is the load torque; The calculation formula of the rectifier control constraint is as follows: In the formula, i a is the AC side current, L is the filter inductance, υ dc is the DC side voltage, υ a is the AC side voltage of the rectifier, R is the resistance; The calculation formula of the inverter control constraint is as follows: In the formula, i b is the AC side current, υ ref is the reference voltage, υ b is the AC side voltage of the inverter; The calculation formula of the current loop control constraint is as follows: In the formula, id * To control the target current, i d is the measured current value; The current constraint is calculated as follows: in max =min(in d ,in maxlimit ) In the formula, i max is the system current value, i maxlimit is the system current extreme value; The calculation formula of the DC transmission line protection constraint is as follows: The calculation formula of the voltage loop control constraint is as follows: In the formula, To control the target voltage, K vp is the control voltage proportional gain coefficient, v d is the measured voltage value, K vi is the control voltage integral gain coefficient; The calculation formula of the voltage fluctuation constraint is as follows: Where Δv is the measured voltage fluctuation value of the system, K f is the voltage fluctuation coefficient.

7. The method according to claim 1, characterized in that The method further comprises: Based on the technical parameters, voltage control parameter reference values, current control parameter reference values ​​of the wind turbines in the current wind farm and the technical parameters, voltage control parameter reference values, current control parameter reference values ​​of the high-voltage flexible DC transmission system, simulation is performed to obtain simulation experimental results; When the simulation experiment result is greater than a preset deviation value, the constraint conditions of the grid-connected optimization model are adjusted.

8. A wind farm wind turbine control and DC transmission network transmission parameter optimization system, characterized in that: The system comprises: An acquisition module is used to acquire the technical parameters of the wind turbines in the current wind farm and the technical parameters of the high-voltage flexible direct current transmission system, and acquire the standard voltage control parameters and standard current control parameters of the wind turbines and the standard voltage control parameters and standard current control parameters of the high-voltage flexible direct current transmission system based on the technical parameters of the wind turbines in the current wind farm and the technical parameters of the high-voltage flexible direct current transmission system respectively; An optimization solution module, used for substituting the standard voltage control parameters and standard current control parameters of the wind turbine and the standard voltage control parameters and standard current control parameters of the high-voltage flexible direct current transmission system into a pre-built grid-connected optimization model, and optimizing and solving the grid-connected optimization model using a particle swarm optimization algorithm to obtain reference values ​​of voltage control parameters and current control parameters of the wind turbine and reference values ​​of voltage control parameters and current control parameters of the high-voltage flexible direct current transmission system; A determination module is used to use the voltage control parameter reference value and the current control parameter reference value of the wind turbine as the optimized voltage control parameter and the optimized current control parameter of the wind turbine, and to use the voltage control parameter reference value and the current control parameter reference value of the high-voltage flexible direct current transmission system as the optimized voltage control parameter and the optimized current control parameter of the high-voltage flexible direct current transmission system.

9. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method according to any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

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