含风电扩展单机无穷大系统不对称故障下的暂态稳定性分析

针对含双馈风力发电机(double-fed induction generator，DFIG)的扩展单机无穷大系统，分析不对称故障下，DFIG接入对系统暂态功角稳定性的影响。基于DFIG阻抗等值模型，依据等面积定则推导不对称故障下含双馈风电系统极限切除角的详细表达式，同时考虑风电比例、风机并网位置两种影响因素对含双馈风电系统极限切除角的影响，从而得到两种影响因素对系统暂态功角稳定性的影响，并分析该影响规律对不同双馈风机模型的适用性。在PSD-BPA中建立含DFIG的扩展单机无穷大系统的仿真模型，对理论分析的正确性进行了仿真验证。

Quantitative Analysis on Transient Stability of Extended Single-Machine Infinite System Containing DFIG under Asymmetric Faults

In allusion to the extended single-machine infinite system containing double-fed induction generator (DFIG), the influence of switching in DFIG on transient angle stability of the system under asymmetric faults was analyzed. Based on impedance equivalent model of DFIG, the detailed expression of the limit clearing angle of the system containing DFIG under asymmetric fault was derived according to the equal-area criterion, meanwhile the effect of the two influencing factors, i.e. the ratio occupied by the wind power and the grid-connected position of the wind turbine, on the limit clearing angle of the system containing DFIG was taken into account, thus the effect of the two influencing factors on transient angle stability of the system was obtained and the applicability of the two influencing factors for different types of DFIG models were analyzed. A simulation model of an extended single-machine infinite system containing DFIG was established in PSD-BPA to verify the correctness of the theoretical analysis. Simulation results show that the results of the theoretical analysis are correct.