Control strategy of permanent magnet synchronous generator of directly driven wind turbine

The control strategy of PMSG should be carefully chosen and designed because it can influence static DC-bus voltage of converter, efficiency of the system and designed capacity of converter. The paper mainly analyses and compares the characteristic of several control strategies of PMSG. In the paper, U_s/f_s = E₀/f_s vector control is put forward to control 2 MW high-power PMSG. Compared with other control strategies, U_s/f_s = E₀/f_s vector control is benefit to decrease the maximal static voltage of DC-bus, and avoids the danger of over-voltage produced by control strategy of PMSG. Meanwhile, it can make the most of the capacity of generator and converter as realizing maximum power capture and transmission though efficiency is a little decrease. The results of simulation and experiment indicate that the method is effective and feasible.