中文摘要：

针对各种基于正反馈的孤岛检测方法不适用于电网电压不平衡的问题,提出一种新颖的基于电压正反馈的孤岛检测方法,将公共连接点电压的负序分量调换相序并进行派克变换得到的q轴电压作为反馈量。仿真结果表明,该方法在电网电压不平衡时不影响并网逆变器的正常运行,在电网断电后能准确迅速地识别孤岛,该方法还适用于电网电压平衡的情况,在IEEE Std.1547定义的最恶劣情况下也能实现正确检测,不存在检测盲区,且能识别伪孤岛。

英文摘要：

Since the conventional islanding detection methods based on positive feedback are not suitable for the grid-voltage unbalance condition,a method of islanding detection based on the q-axis voltage positive feedback is proposed,which is obtained by the phase-sequence change and Park transform of the negative sequence voltage at the common coupling point. Simulative results show that,the normal operation of gridconnected inverter in the grid-voltage unbalance condition is not affected and the islanding is detected correctly and quickly. It is also suitable for the condition of balanced grid-voltage and both true islanding and false islanding can be correctly detected in the most severe conditions defined by IEEE Std.1547,without any undetectable zone.