Equivalent Substitution and Stability Analysis of Parallel Inverter

In power electronic circuits, H-bridge inverter is a kind of basic nonlinear circuit topology. Multi-inverters in parallel can realize large capacity power supply and redundant power supply, so it is recognized as one of the important directions of current development about inverter technology. In this paper, we study the single phase H-bridge inverter parallel system which is under double closed loop feedback control and analysied topology module[1]. Through theoretical analysis, calculation and simulation comparison, the parallel system is equivalent to the single phase inverter. This system is a time-varying parameter system and we found in the research that it is easy to produce fast-scale instability in time domain, and slope compensation is a simple and effective method[2]. Based on the nonlinear theory, the theoretic requirements of slope compensation signal amplitude are analyzed and calculated.