Effects of switching frequency and input voltage on efficiency of chopper-controlled series-connected DC machines

Chopper-driven operation of a conventional, series-connected DC machine is examined for the purpose of studying operating efficiency of the chopper circuit and DC machine. After expressions are developed for the steady-state circuit waveforms, component loss models are developed, and losses predicted for differing values of switching frequency and DC input voltage to the chopper circuit. Results show that most efficient operation of the chopper circuit and DC machine occurs with high-frequency operation.<>