Abstract: Buck-boost inverters found widespread applications in grid-connected systems, Uninterruptible Power Supplies (UPS) and other applications requiring voltage regulation above and below the output ac voltage. This study focuses on modeling of the working principles, computer simulation and design consideration of full bridge inverters. About 3 circuit configurations are described with various switching approaches and operation principles where comparison analysis between these circuits is conducted with respect to the output voltage, power, switch voltage and dissipated power. The simulation results stated that the proposed configuration of four-switch inverter with improved stability realized optimum output performances with reduced switching losses. Power electronic simulation platform (PSIM) and Matlab/Simulink platforms are used for simulating the circuit behaviors where applying both platforms in simulation process provides this study with additional tools in selecting the optimum circuit and results comparison.