The influence analysis of parameters mismatch in the input series output parallel system

In this paper, an output current differential control method is presented for an input series output parallel (ISOP) system. The method includes a specialized output current sharing loop to achieve power equilibrium in modules, and avoids steady- state sharing errors due to parameters mismatch. However, in the transient process, inconsistent parameters can produce individual input voltage and output current overshoots that have the potential to damage devices. This study analyses the effects of parameters mismatch on the dynamic characteristics of the system, and the voltage and current overshoots of modules are calculated. The results will help in device selection. The analysis method can also be applied to other control methods. Simulated and experimental waveforms of a 300-W prototype verified the analysis results.