具有不同转子匝数的新型双馈风力发电机低电压穿越能力的瞬态性能分析

Transient Behavior Analysis of Low Voltage Ride Through Ability of the DFIG with Different Numbers of Turns in Rotor Windings

分析了转子绕组匝数可变的双馈风力发电机在电网电压跌落时的瞬态性能。该电机通过转子绕组的匝数变化,来抑制转子电流上升,实现低电压穿越。本文建立了基于Matlab/Simulink的仿真模型,分别对全电压跌落和部分电压跌落两种情况下的低电压穿越能力进行分析,并讨论匝数变化的参数n取值对于瞬态性能的影响。分析得出了不同电压跌落情况下,绕组匝数对电机性能影响均有所不同。最后,本文给出了7.5kW样机的测试结果,验证了该新型结构双馈风力发电机能够有效实现低电压穿越。

This paper analyzes the transient behavior of a doubly fed induction generation（DFIG） with split rotor windings during grid voltage dips.By changing the number of the turns of the rotor windings,the rising current can be limited and therefore the low voltage ride through（LVRT） ability can be achieved.A dynamic model based on Matlab Simulink is built to evaluate the LVRT capability on both full voltage dip and partial voltage dip occasions,and to discuss the value of n（turns changing parameter） for the influence on the LVRT capability.The effect of n on the performance of DFIG is different under different voltage dip occasions.Finally,the test results of a DFIG prototype（7.5kW） are presented to prove the idea.