非线性装置的谐波分析模型

Modelling of Nonlinear Devices for Power Harmonic Analysis

提出了一种采用多项式逼近非线性装置稳态特性的谐波分析新模型———时域稳态模型。阐明了建立时域稳态模型的一般数学方法 ,并在此基础上提出了一种工程适用的谐波分析模型———受控源综合模型 ,这类模型适用于电力网络的时域非线性稳态分析。

A new model of nonlinear devices for power harmonic analysis is derived rigorously first. The model representing the time domain steady state characteristics of nonlinear devices is presented on the basis of polynomial fits to the time domain waveform of the output current versus system supply voltage. This mathematical model can be straightforwardly transfered to an equivalent circuit model composed of a linear capacitance (inductance) and a multidimension controlled suorce. The paremeters of the equivalent circuit model are random variables obtained from the statistic properties of the data acquisition of the output current. This model is useful for analysts to perform harmonic studies both in linear and nonlinear power systems by the use of general purpose simulators. As examples, the plots showing harmonic analysis are drawn by the commonly used softwares MATLAB and MathCAD.