There is a growing demand for high power density, high efficiency, and high reliability (H 3 ) single-phase power converters in power electronics applications. These H 3 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 H 3 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 H 3 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.