Power Loss Analysis of a Back-to-Back Switching Single-Inductor Multiple-Output Inverter

In this paper, a modified single-inductor multiple-output (SIMO) boost-type inverter for producing multiple sinusoidal-like outputs is proposed. Unlike its predecessors with external blocking diodes, this SIMO inverter employs two identical back-to-back connected MOSFETs, which improves the power efficiency and ensures a unidirectional current flow across the main inductor and the output branch for proper circuit operation. A more systematic approach for analyzing the power distribution of the SIMO inverter is presented and a general power efficiency equation is analytically derived. The proposed method of estimating the power efficiency serves as a useful guideline for designing a highly-efficient SIMO inverter. It is experimentally verified that the measured power efficiency under balanced load condition is 86.6%, which agrees closely with the theoretical value of 84.5%. Likewise, the measured power efficiency under unbalanced load condition is 87.9% which agrees very well with the predicted value of 87.6%.