Monitoring of Current Balance in Parallel-connected Power Converters

Power semiconductors are often paralleled to drive currents beyond the single module current rating, thereby increasing the converter power capability. However, current sharing between parallel devices is not necessarily granted. In addition to load balancing techniques (e.g. component selection and arrangement) parallel converters would benefit from monitoring of effective current sharing. This paper introduces a simple, low-cost current balance monitoring technique based on encoding the analogue current measurement as a digital signal. The effectiveness of such technique is proven by Matlab/Simulink simulation as well as experimentally.