Research On Particle Swarm Optimization Algorithm For Doubly-fed Wind Power System

With the acceleration of globalization,the energy crisis and environmental degradation are increasingly prominent.Wind energy as a kind of clean and renewable energy has attracted much attention,and wind power generation technology has also developed rapidly.For the doubly-fed wind power system,the traditional converter control strategy is a little insufficient in terms of stability,control performance,efficiency and reliability.In order to improve the control performance of the converter in doubly-fed wind power generation system,this paper designs and optimizes the parameters of the converter for the machine side converter,the grid-side converter control and the grid-side filter,respectively.Firstly,the Particle Swarm Optimization(PSO)algorithm is easy to fall into the local optimal region and converge slowly when dealing with complex nonlinear optimization problems,so the random weight and particle adaptive mutation are introduced.Hybrid PSO(HPSO)is designed,and its high convergence sp eed and accuracy are verified by testing function.Hybrid Multi-Objective PSO(H-MOPSO)based on Pareto optimization is designed and applied to further research to verify the effectiveness of the proposed algorithm.Secondly,based on the electric-mechanical port controlled Hamiltonian(PCHD)model of the doubly-fed wind power generation system,and combined with the full-order non-singular terminal sliding mode rotational speed outer loop,A passive controller based on PCHD model is designed.The controll er parameters are designed by HPSO algorithm.The simulation results show that the controller not only improves the stability of wind power system,but also improves the anti-disturbance ability of the system.Then,for the LCL filter in the grid-side converter,in order to save the cost and reduce the loss at the same time to ensure that the filter has good filtering performance.In this paper,a parameter optimization method of passive damped LCL output filter based on H-MOPSO algorithm is presented.Based on the complex frequency domain model of LCL grid-connected output filter,the influence of filter parameters on filter performance,resonance suppression and damping loss is analyzed,and the optimal design model of filter parameters is established.Compared with the traditional linear weighted multi-objective optimization results,the superiority of H-MOPSO in solving the multi-objective optimization problem with conflicting sub-objectives is verified.Finally,in order to improve the performance of the grid-connected converter control system after LCL filtering,and improve the robustness of the system under external disturbances and parameter fluctuations,a grid-connected converter controller based on full-order non-singular terminal sliding mode is designed.On this basis,in order to achieve better control performance,HPSO algorithm is used to optimize the controller parameters.Simulation results validate the effectiveness of the HPSO algorithm and also verify that the designed controller has good dynamic and static performance and strong robustness.