中文摘要：

为了充分利用风能并提高风电系统的稳定性，提出基于z源逆变器的变速定桨风力发电系统全风速功率控制策略。通过调节直通占空比对电机转速进行控制，实现全风速范围内的功率控制。在最大功率点跟踪（MPPT）阶段，控制发电机转速在最佳值；在恒转速阶段，控制电机转速在其额定值；在恒功率阶段，引入气动功率外环，控制电机进入失速区运行，实现恒功率控制。最后在Matlab中进行仿真验证，仿真结果表明了所提控制策略的可行性与有效性，系统能很好地跟随风速的变化，实现了全风速范围内的功率控制。

英文摘要：

In order to make full use of wind energy and improve the stability of wind power system, full range power control strategy for variable-speed fixed-pitch wind energy conversion system based on Z-source inverter is proposed.It adjusts its unique shoot-through duty cycle to control the speed of generator for achieving the power control in the full range of wind power system.At the maximum power point tracking（MPPT） stage,it controls the speed of genera- tor at its best value.At the constant rotational speed stage,it controls the speed of generator at its rated value.At the constant power stage, pneumatic power outer loop is introduced for achieving constant power control.Finally, the exper- iment is carried out in Matlab.The simulation results show that the proposed control strategy is feasibility and effec- tiveness, system can be very good with the wind speed change, the power control in the full range is realized.