Control strategy research of direct driving type wind turbine

ZHOU Ying-hua， GUO Ting-fu， JIANG Ke-jie
（The Newunited Institute of Wind Power Equipment Technology， Changzhou 213011， China）

Abstract： Aiming at the reliability and lifetime of direct driving type wind turbine，for large torque and rotate speed vibration range and continue long time in conventional control strategy result in the damage to wind turbine，the characteristics and needs of direct driving type wind turbine technique were summarized and conventional control strategy theory was stated. The shortage of conventional control strategy was analyzed. On this basis，an optimal control strategy theory was proposed. In this theory，a torque ratio coefficient was added to control strategy of converter. By means of simulation and test platform experiment，the experimental results show that the performance of this optimal control strategy is superior to conventional control strategy. At the same condition of wind speed oscillation，the wind turbine of optimal control strategy than conventional control strategy，the torque and rotate speed vibration range reduce forty percent and continue time reduce one third，the damage to wind turbine is decreased. The results indicate that，by this optimal control strategy theory，the reliability of wind turbine is enhanced，the lifetime of wind turbine is prolonged.
Key words： direct driving type wind generator； control strategy； optimal； torque ratio coefficient