风电并网逆变器控制方法研究

Study of the Control Methods in Wind Power Grid-connected Inverter

为了降低逆变器输出电流的开关频率谐波分量,在并网逆变器设计中引入三阶的T型滤波器,推导了并网逆变器的数学模型。并网逆变器的控制策略就是选择合适的变量控制其桥臂输出电压,在保证系统稳定运行的同时,采用电流闭环控制技术,控制并网输出电流以满足系统要求。最后,在实验平台上完成模拟风力发电系统并网实验,并在2 kHz开关频率下,将采用两种输出滤波器结构的并网逆变器进行对比实验。实验结果验证了文中提出的控制方法对整个控制系统的有效性和实用性。

In order to reduce harmonic components of output current switching frequency, three-order T-types filter is introduced in grid-connected inverter,the mathematical model of grid-connected inverter is deduced.Its control meth- ods regulate the bridge-arm output voltage, the current close-loop control technique is adopted, and the inverter output current content the system steady demand.Finally,the wind power grid-connected experiment is accomplished under 2 kHz switching frequency,the inverter of two output filter is adopted in contrast experiment.The experimental results verify that the proposed control scheme is availability and correct.