配电网中谐波源检测方法的研究

Study of Detecting Harmonic Sources' Method in Distribu tion Systems

介绍了配电网中谐波源探测的一种新方法——临界阻抗法 (CIM)。该方法的原理是比较戴维南等效回路中两个谐波电压源的大小 ,取较大的一个作为主谐波源。通过对于公共耦合点的电压和电流的测量可以引入临界阻抗的概念。进行了临界阻抗法在电网处于不同情况下的基本理论分析 ,并做了一系列的系统校验 ,阐明了临界阻抗法在谐波源检测中的正确性。

In this paper, a new method for detecting harmonic sources in distribution syste ms-“critical impedance method” (CIM) is proposed. The principle of CIM is to c ompare two magnitudes of harmonic voltage sources in the Thevenin equivalent cir cuit and choose the larger one as the main harmonic source. A critical impedance is introduced to “measure” the equivalent harmonic voltage source through the measurements of voltage and current at the point of common coupling (PCC). The fundamental theory of CIM in different situations is discussed in details. A ser ies of simulation case studies show that the CIM is correct in detecting harmoni c sources.