Dual-Mode Double-Carrier-Based Sinusoidal Pulse Width Modulation Inverter With Adaptive Smooth Transition Control Between Modes

Three dual-mode boost-buck-derived inverters with smooth transition between modes have been proposed: 1) boost-full bridge inverter; 2) boost-H5 inverter; 3) boost-dual buck inverter. For the same topologies, in conventional control method, the first stage is needed to boost input voltage to a constant high voltage, and the second stage is for sinusoidal inverting. However, in the proposed three inverters, either buck or boost mode works at a single time, thus, only one switch works at a high switching frequency. In this way, a lot switching loss can be reduced, and moreover, since the voltage across the middle capacitor is smaller than the conventional constant high voltage, the further switching loss mitigation is possible. In order to achieve smooth transition between the two modes, a double-carrier-based sinusoidal pulse width modulation (SPWM) is proposed. Other than this, three advanced modulation methods are proposed: 1) double-carrier with different frequencies; 2) double-carrier with different magnitudes; and 3) double-carrier with different frequencies and magnitudes. Following that, the loss distribution in every component is provided and the California Energy Commission efficiency of these inverters under different input voltage conditions is compared. Finally, the experimental results show the dual-mode double-carrier-based SPWM inverter can improve the efficiency by 2% than the traditional constant dc bus voltage solutions.