Abstract:

Vector control technique of grid voltage orientation is often applied in ACexcited variable speed constant frequency (VSCF) wind power generation to implement decoupling control of active power and reactive power. Using this method, maximum wind energy tracking can be realized. However, the net power delivered to the grid in the maximum wind energy tracking mode does not reach the upper limit. In this paper, a novel maximum power point tracking control strategy is presented to deliver a maximum amount of power to the grid. The maximum power point can be tracked automatically without measuring wind speed, and the control is independent of optimal turbine power curve. It has excellent dynamic and static performances and good robustness. Simulation and experimental results confirm validity and accuracy of this technique.

Key words: variable speed constant frequency (VSCF); grid voltage orientation; decoupling; maximum power point tracking (MPPT)