Comparison between two control strategies for input-series-output-series inverters system

Abstract

Input-series output-series (ISOS) inverters system is very suitable for application of high input voltage and high output voltage. The significant issue of the system is to ensure input voltage sharing (IVS) and output voltage sharing (OVS) for all the constituent modules. This paper presents comparison and analysis between two control strategies for this novel configuration. A practical implementation of the IVS control, i.e., the three-loop strategy based on the inductor current feedback can achieve IVS but can not always achieve OVS. While a detailed realization of compound control, that is, the three-loop strategy based on the capacitor current feedback can achieve IVS and simultaneously achieve OVS unconditionally. The comparative results indicate that the latter strategy is superior to the former one. Simulation and experimental results are put forward to verify the theoretical analysis.