Application Criteria for Nine-Switch Power Conversion Systems with Improved Thermal Performance

Nine-switch converter is a reduced-switch equivalence of the widely used twelve-switch back-to-back converter. Like other reduced-switch topologies, the nine-switch converter experiences operating constraints, which may limit its efficiency. This is however not universal, meaning losses of the nine-switch converter can at times be lower than the twelve-switch back-to-back converter. The scope of this paper is thus to identify application criteria for the nine-switch converter, which upon met, will lead to lower conduction and hence total losses. Loss distribution among switches of the nine-switch converter is also investigated since it can greatly influence reliability of the overall converter. Experimental results obtained have promptly justified the analytical reasoning formulated.