Direct-drive Wind Generation System Control Strategies Research In Microgrid

In the last twenty years, distributed energy sources(wind, photovoltaic, power flow, etc.) have attracted more and more attention. The randomness,discontinuity,dependence on the environment of distributed energy has seriously hindered the wide application and the realization of large-scale power generation and grid connected power generation. Wind power generator is one of the important generating units in micro grid. The coordinated control of wind power generators and energy storage in micro grid islanding mode,which is very important for the stability and efficiency of the micro grid.Firstly,the mathematical model is introduced,and based on the mathematical model under d-q coordinates a simple speed closed loop control method is studied. By means of Baez theory,the theoretical value of wind energy utilization coefficient and maximum power capture of wind turbines are derived.Maximum power tracking control is one of the most important ways to improve the utilization of wind energy. According to the shortage of the various maximum power tracking control method, understand the characteristics of the typical maximum power tracking control method through literature. Based on the analysis of the control features of the different maximum power tracking methods in different cases, a maximum power tracking control method based on mode switching is proposed. Simulation results show that the method is reliable,accurate and effective.In the case of micro grid wind power generator in the reservoir can tend to saturation and light load,the generator can't run in the maximum power tracking control mode,because the system does not require so much energy. In order to balance the energy and system stability of the system, a given power tracking control method based on fuzzy PI control is proposed. Simulation results show that the method is reliable,accurate and effective.