中文摘要：

风电机组连锁脱网事故是集群风电迅速发展过程中出现的新问题之一。针对中国频繁发生的风电机组连锁脱网事故，对事故机理进行初步研究。首先，分析连锁脱网事故的典型发展过程及时空尺度；然后，构造集群风电接入系统的理论原型，研究风电机组共模跳闸机理及事故演化发展主导因素；最后，基于实际电网参数及拓扑结构，重演风电机组连锁脱网事故，从重载工况下网架结构电压稳定性、双馈风电机组运行方式2个角度分析风电机组连锁脱网事故频发的原因，提出相应改善措施。

英文摘要：

Cascading trip-off of wind turbine generators is one of the new problems with the fast development of wind farm clusters. Aiming at the cascading trip-off failures frequently occurring in China,： this paper makes ＇a preliminary research. Firstly, the typical development process and time-spatial frame of the failures are analyzed. Furthermore, a prototypical system with wind farm clusters is constructed, based on which, the mechanism of common mode tripping and some dominant factors in the failure evolution are studied. Finally, based on the topology structure and parameters of an actual power grid in China, the cascading trip-off failure is simulated. Some countermeasures are discussed from two aspects： enhancing the voltage stability of the power grid under heavy load condition and improving the operation modes of the doubly fed induction generators.