Parallel-Inverter System With Failure Isolation and Hot-Swap Features

This paper presents the analysis, design, and implementation of a parallel-inverter system with failure isolation and hot-swap features. The system is controlled with a system control unit to achieve output voltage regulation, inverter synchronization, and the aforementioned features. By incorporating a current- weighting-distribution control, the system allows inverters with identical or different power ratings. The failure isolation feature is achieved with a scanning circuit, a resistor-capacitor filter, and transistors, which are also used in achieving the hot-swap one. In the proposed system, power capacity can be readily expanded, and inverter-failure disturbance can be correspondingly reduced. Experimental results that are obtained from a six-inverter system have illustrated the discussed features and significantly demonstrated its feasibility, improving system reliability, and stability.