Opportunities for Performance Improvement of Single-Phase Power Converters through Enhanced Automatic-Power-Decoupling Control

There is a growing demand for high power density, high efficiency, and high reliability (H3) single-phase power converters in power electronics applications. These H3 converters, which are equipped only with very small energy storage components, involve large-signal operation and exhibit highly coupled and nonlinear characteristics. Existing controller designs for these converters are based on small-signal models, and may not attain satisfactory dynamic performance and robustness. This paper presents a nonlinear control method based on the technique of input-output feedback linearization and the automatic-power-decoupling control strategy for the H3 converters. The controller not only achieves global system stability and enhanced dynamic performance over existing control solutions, but also enables us to exploit the full potential of H3 single-phase converters, thereby providing new application opportunities. Simulations and experiments are carried out to demonstrate the feasibilities and to verify the performance of the proposed control.