并网型交流励磁变速恒频风力发电系统控制研究

Investigation of Control for AC-exited VSCF Wind Power Generation System Connected to Grid

并网型交流励磁变速恒频风力发电系统存在不同的运行区域,各运行区域对应的控制方式有所不同。文中讨论了并网型交流励磁变速恒频风力发电系统的运行区域,指出并网控制和功率解耦控制是发电机重要的控制模式。在讨论双馈异步发电机数学模型的基础上,将磁场定向矢量控制技术应用于发电机控制,探讨了基于定子磁链定向矢量控制的并网型交流励磁变速恒频风力发电系统功率解耦控制策略和并网控制策略。构建了1台10kW的实验机组,对并网控制和功率解耦控制进行了完整的稳态、动态实验研究。实验结果表明,风力发电机控制性能优良,不但可在变速情况下可靠并网,而且并网后还能在变速恒频运行的基础上实现有功功率、无功功率的解耦控制。

There are different operation areas of AC- excited VSCF（variable-speed constant-frequency） wind power generation system connected to grid, of which the corresponding control modes are also different. By discussing the operation areas, the paper pointed out that grid-connection control and decoupled power control were important control modes of the generator. Based on analysis of the mathematic model of DFIG, field-oriented vector control technique was transplanted into DFIG control. Later, the strategies of decoupled power control and grid-connection control were discussed independently. These strategies are all based on stator flux linkage oriented vector control method. Furthermore, a 10kW experimental set was built, on which the steady and dynamic experimental research of grid-connection control and decoupled power control was conducted. The experimental results show that DFIG not only can be connected to grid safely at variable speed, but also can achieve decoupled control of active power and reactive power on the basis of VSCF operation after grid-connection.