三相不对称系统任意次谐波电流检测新方法

摘要

A new algorithm for detecting random harmonic current in unbalanced three phase system is proposed. An arbitrary initial phase angle is constructed, whose sine and cosine signals have the same frequency with the random harmonic current needed to be detected. It is used to conduct correlation operation with three phase current, and the components of positive, negative and zero sequences of random harmonic current can be detected. By adding the three components, the random harmonic current of three-phase four-wire system can be obtained. Without phase lock loop, the circuit is simpler. Both the theoretical analysis and simulation results demonstrate the correctness of the method.%　　提出了在三相不对称系统下，一种新的检测任意次谐波电流的方法。该方法通过构造任意初相角、具备与需要检测的任意次谐波相同频率的正弦信号和余弦信号，使其与三相电流进行相关运算，可分别检测出任意次谐波电流正序分量、负序分量和零序分量，将三种分量相加即可得到三相四线制系统任意次谐波电流的检测结果。该方法不存在锁相环电路，简化了电路结构。理论分析和仿真结果都证明了所提方法的正确性。