Research On Primary Frequency Modulation And Adaptive Inertia Control Strategy For Wind Turbines

The randomness and volatility of wind power output cause the fluctuation of wind power.In order to ensure the reliable grid-connected wind power,the main network needs more reserve capacity,which increases the operation cost of power grid.The expansion of wind power development scale,and the characteristics of the centralized development of wind power in China,the demand for wind power to play the role of in power grid and smooth its output power was put forward.In this paper,it is of great theoretical significance and practical value to carry out research on two aspects of adding auxiliary equipment and improving control strategy for wind turbines.The main research work and innovation achievements of this paper included:(1)In this paper,a mathematical model of wind turbine generation and frequency modulation(FM)is established.The model of wind turbine and its control structure is introduced,and the main control parameters of wind turbine control structure are analyzed.This paper introduce several main frequency control methods of the existing variable speed constant frequency wind turbine,compares their advantages and disadvantages,and lay the foundation for the improvement wind turbine primary frequency control strategy and adaptive inertia control strategy.(2)In this paper,a primary frequency control strategy of wind turbine with energy storage is presented.In order to improve the FM capability of DFIG,a new energy storage system is put forward on the DC side of DFIG,and an improved strategy based on the original FM strategy of the turbine is proposed to realize the integrated control of the system frequency of wind turbines.The simulation results verify that primary frequency modulation control strategy of wind turbine with energy storage can effectively improve the FM ability of DFIG.(3)In this paper,the adaptive inertia control strategy of wind turbines is presented.In order to reduce the fluctuation caused by wind speed in the turbine control system,a wind speed aerodynamic filtering method based on combined wind speed and an adaptive inertia control strategy are presented.The adaptive inertia control strategy based on the output power variation can provide fast and smooth active power support,to realize the goal of fast track and stable output power.The simulation results show that the PMSG has better fluctuation ability under the proposed control scheme.