宽风速运行的定子双绕组感应电机风力发电系统拓扑及控制策略

Topology and Control Strategies of Dual Stator-Winding Induction Generator Wind Power System Over a Wide Wind Speed Range

介绍了一种适用于宽风速范围运行的新型定子双绕组感应发电机风力发电系统,其拓扑特点是将控制侧励磁变换器的直流母线经二极管与功率侧直流母线相连。在低风速区,利用电压泵升原理将励磁变换器的直流母线电压泵升至指令值,电能由控制侧直流母线端输出,拓宽了系统在低风速下的风能利用能力;在高风速区,功率绕组侧输出电压可上升至指令值,并联二极管断开,电能由功率侧整流桥的直流母线输出,控制侧变换器调节系统励磁无功保持输出电压恒定。该发电系统拓扑及控制方法实现了系统在宽风速范围内均能输出恒定的高压直流,可简化后级并网逆变器的结构和控制。在一台额定37 kW/DC 600V的样机上进行了实验研究,结果表明该风力发电系统的可行性和控制策略的有效性。

This paper presents a novel dual stator-winding induction generator （DWIG） wind power system applicable to wide wind speed operation, whose specialty is that the output terminal of the excitation converter on the control side is connected with the power side in parallel through a unidirectional diode. The DC bus voltage of the excitation converter on the control side is pumped to the given value under low wind speed. The electric energy is outputted from the DC bus. These broaden the utilization ability of the wind energy under low wind speed. In the high wind speed area, the output voltage on the power side rises to the set value and is maintained constant by modulating the reactive current from the excitation converter. The electric energy transmission is fulfilled by the rectifier on the power side because of the diode＇s turn-off. The topology and the control scheme together make the DWIG output the given high DC voltage over a wide wind speed range and simplify the structure and control of the latter grid-connected inverter. Experimental results on a 37kW/DC 600V prototype are provided to demonstrate the effectiveness and accuracy of the proposed theoretical analysis and control strategies.