适合直接驱动型风力发电系统的飞跨电容型变流器

Flying capacitor converter suitable for direct-drivewind power generator system

直接驱动型风力发电系统需要全功率变流器作为与电网的接口,飞跨电容型多电平变流器是首选方案。在大功率电力电子变流装置的实现上,一个重要的问题是大功率器件的工作频率较低,无法应用PWM技术等优秀的调制技术。因为载波相移正弦波脉宽调制技术(CPS-SPWM)的等效开关频率高,采用该技术后可以引入各种先进的控制策略,优化系统的性能指标,同时改善输出波形,减小了滤波器容量。仿真和实验验证了上述结论的正确性。

The full- scale high power converter is needed in direct- drive wind power system as the interface between generator and grid ,of which the flying capacitor multilevel converter is the optimal choice. The working frequency of high power devices is too low to apply the excellent modulation technique in the implementation of high power electronic converter,such as PWM. As the equivalent switching frequency of CPS- SPWM （Carrier Phase- Shifted SPWM ） technique is high, based on it ,various advanced control strategies can be used to enhance system performances,improve output wave form and reduce filter capacity. Simulation and experiment verify its correctness.