中文摘要：

针对基于电力线信号技术的分布式发电系统孤岛检测和保护方法中存在的问题,该文提出一种改进的信号产生和检测方法。利用变电站侧两个双极性晶闸管交替导通,解决了单极性晶闸管频繁导通可能导致的信号变压器饱和问题;通过改变信号发生和检测方式,提高了对发电机孤岛状态的检测速度;此外对改进后检测过程中的信号干扰因素进行理论分析,并推导出用于选择信号发生装置的估算公式。通过仿真和实测数据验证表明,检测信号与干扰信号能够清晰地分辨出来,从而实现在不影响信号检测稳定运行情况下将信号检测速度提高一倍的目标。该改进方法为电力线信号技术在分布式发电系统孤岛检测中的实际应用提供了理论基础与依据。

英文摘要：

To deal with the issues remaining in existing power line signaling technique based anti-islanding protection approach for distributed generation system, this paper proposes the improved schemes for signal generation and detection. By firing the bi-directional thyristors alternately, the signal transformer can be prevented from saturation caused by one directional thyristor firing frequently and the anti-islanding detection can be speeded up by using new signal generation and detection ways. Also, the causes of signal interference were analyzed and the estimation formulas for selecting signal generator device were developed in this paper. It is verified that the detection signal and interference signal can be clearly recognized by simulation and field tests. It indicates that the goal of making detection rate doubled can be achieved without impacting stable operation for signal detection, which provides the theoretical foundation for power line signaling technique based anti-islanding protection widely used in the distributed system.