A simple model for a thyristor-driven DC motor considering continuous and discontinuous current modes

摘要

A simple model for a thyristor driven DC motor is rigorously established. The derivation is based on the machine equations and on the definition of a pseudoinstantaneous mean-value function. The influence of the converter on the voltage applied to the DC motor is considered. The final model includes all significant effects, has the same structure for continuous and discontinuous current conduction modes, and allows simple control synthesis. The model is compared to the classical model of a DC motor, and the differences are highlighted. It is shown that, with the proposed model, it it easy to understand the influence of a thyristor converter on the dynamic performance of a DC motor, and, therefore, it has a significant educational aspect. A dual-mode adaptive current controller is designed using this model. Experimental and simulation results are compared to validate the work.