用于DFIG风电场接入电网的固态变压器控制策略  

Control Strategy of Solid-State Transformer for DFIG-based Wind Farm Grid Integration

作　　者：李程[1] 廖勇[1] 

机构地区：[1]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400044

出　　处：《电源学报》2014年第6期101-107,120,共8页Journal of Power Supply

摘　　要：通过对电网故障情况下DFIG定、转子电压、电流过渡过程机理的分析,提出了通过控制固态变压器(SST)风场侧换流器电压的下降和故障切除时电压上升的斜率,来抑制电网故障过程中因电网电压突变而使双馈发电机的电压、电流以及转矩产生的冲击。分析了通过SST控制风场侧电压下降斜率与能量传递、SST直流链等效电容容值的关系,同时也分析了电网故障过程中,风场侧电压与电网电压跌落的关系。最后建立了双馈风力发电机、SST及其控制系统的模型,并针对电网三相短路故障进行了仿真计算,进一步验证了所提控制策略的正确性和有效性。As a new connection mode for solving problems with doubly fed induction generator （DFIG）-based wind farm grid integration, solid state transformer （SST） has attracted more and more attention. Through analyzing the transient process of DFIG including stator and rotor voltage and current when a fault occurs or is cleared, the method of controlling the descending slop or rising slop of wind farm side voltage source converter＇s output voltage respectively is proposed to suppress the impact of voltage, current and torque on DFIG. The relationship among the slope of wind farm side voltage, energy transfer and equivalent capacitance value of SST＇s DC-link was analyzed. Meanwhile, the relationship between wind farm side voltage and grid voltage sag was also analyzed. Lastly, the models of DFIGs, SST and its control system were established. The correctness and effectiveness of the control strategy are verified by simulation for three-phase short circuit fault of grid.

关 键 词：固态变压器 双馈风力发电机 风场侧换流器 三相短路故障 

分 类 号：TM42[电气工程—电器]