Modeling and simulation of a cycloconverter drive system for harmonic studies

This paper discusses the steady-state harmonic modeling and simulation of a cycloconverter drive system (CDS). The operation and control of a cycloconverter drive and a synchronous motor load were modeled in the time domain. Based on the duality principle of electric and magnetic circuits, four types of three-phase transformer models with detailed nonlinear magnetizing characteristics were implemented. The harmonic behaviors of the entire system were studied under several worst operation conditions. The goal of this paper is to understand the harmonic problems associated with a CDS from an integrated system point of view, with special attention given to harmonic filtering and cancellation effect of converter coupling transformers