Optimum relation based maximum power point tracking of a PMSG wind generator through converter controls

A maximum power point tracking (MPPT) algorithm has been implemented on a permanent magnet wind generator feeding a power grid. The algorithm is based on fixed relationship between the maximum converter power with the dc voltage for various wind speeds. The algorithm does not require any direct measurement of wind speed or the turbine parameters. The optimum relationship based MPPT controller generates the reference values for generator speed and converter voltage. The wind speed change is detected through the variation of converter power which resets the reference values and the PI controllers adjust the modulation indices of the converter voltages for optimum power transfer. The MPPT algorithm was tested on the permanent magnet synchronous generator represented through a detailed dynamic model of the generator, the generator turbine, drive train and the converter system. Simulations studies show that the wind turbine can deliver power to the grid maintaining optimum power coefficient for randomly varying wind conditions.