Computer-Aided Analysis of a Multiphase Chopper-Driven DC Series Motor and Test Results on a Microprocessor-Based Three-Phase Chopper Drive

A comprehensive digital computer-based analysis using a state-space model which predicts the performance of a dc series motor controlled by a multiphase chopper is presented. The analysis is based on the formulation of system equations in multivariable state-space form and takes into account the nonlinear magnetization curve and the variation of field inductance with load current. The predicted results based on this analysis are shown to agree with the test results on a practical drive system developed for this purpose in which the dc series motor is driven by a microprocessor-based three-phase thyristor chopper. The control circuit development for the practical drive is briefly described.