Energy efficient DC to AC power conversion using advanced controllers and novel voltage trajectories

A typical DC:AC conversion system consists of two stages, a DC:DC converter to generate the necessary bus voltage followed by an inverter which generates the desired AC output. A modification of this system is proposed for the purpose of reducing switching losses. The proposed two-stage system consists of a buck converter which produces a mixed (DC+AC) signal which is fed to a traditional inverter. This mixed signal is designed such that it reduces the switching loss across the inverter switches while still providing the necessary voltage for the inverter input. Backstepping controllers are designed to achieve output voltage tracking objectives for both stages. Lyapunov stability analysis and simulation results validate these controller designs. Efficiency and THD comparisons are made between the typical and modified systems.