Frequency Domain Modeling of Nonlinear Loads, considering Harmonic Interaction

JOAQUIN CAICEDO; A. A. ROMERO; H. C. ZINI

Bogotá

Workshop; IEEE Workshop on Power Electronics and Power Quality Applications; 2017

IEEE

Large-scale penetration of power electronic-based loads (e.g. compact fluorescent lamps and plug-in electric vehicles) is a concern in modern power distribution networks due to the resultant increase in harmonic distortion. Harmonic analysis in frequency-domain is suitable to deal with the above problem due to the high computational efficiency. This type of analysis relies on the accuracy of nonlinear load models. The coupled admittance matrix model is an accurate frequency-domain representation due to its capability to characterize interaction between harmonic voltages and currents of different order. This paper presents the development of a coupled admittance matrix model for a single-phase rectifier with resistive load, obtained by using simulations in Matlab/Simulink. According to the literature, the admittances of the matrix depend mainly on the phase angles of the harmonic voltages. The model considers this dependence by means of the tensor representation of the admittance matrix. In addition, the effect of the variation of voltage distortion magnitude on the model is analyzed, considering the ranges established by standards for each harmonic order. One thousand cases with different levels of voltage distortion were carried out to test the model. The validation is achieved by comparing the aforementioned results with the respective simulations in time domain. Finally, the conclusions of the work are pointed out.