新型双转子结构风力发电系统及其双模功率控制策略

A Novel Wind Power System With a Dual-rotor and the Dual-mode Power Control Strategy Thereof

研究了一种新型风力发电机系统,包括发电机、调速电机、行星齿轮和风力机,发电机与太阳轮连接,调速电机与内齿圈连接,风力机轴与行星架连接。分析了不同工况下两台电机的工作模式与功率流的变化,针对此种结构提出一种全风况下转速转矩模式控制策略,低于额定风速时调速电机转速控制能够实现发电机恒频并网,高于额定风速时通过控制调速电机转矩限制发电机输出有功功率在额定值附近。对控制策略进行仿真研究,并给出转速转矩控制平滑切换规则,搭建了双转子风力发电实验平台,实现了并网操作,验证了该系统结构的可行性与控制策略的有效性。

A novel wind power system was proposed, which was composed of a generator, an auxiliary motor, a planetary gear and a wind turbine. The generator was connected to the sun wheel, while auxiliary motor was connected to the ring gear, and the shaft of the wind turbine was connected to the planetary carrier. The working mode and power flow about this type of structure in different working conditions were presented, and a novel speed-torque mode control strategy in all wind conditions was proposed. The generator can be connected to the grid by controlling the speed of the auxiliary motor when the wind velocity is under the rating value, and the active power of the generator can be kept around the rating value by controlling the torque of the auxiliary motor when the wind velocity is above the rating value. The dual-mode smooth switching rule was given, and the validity was tested by the simulation study. Moreover, experimental results were given to verify the theoretical analysis, and the feasibility of the system structure also was verified.