A New Bidirectional AC-link Microinverter Based On Dual Active Bridge Topology

摘要

AC link inverters have advantage that it doesn't require bulky decoupling capacitor unlike DC link inverters. A bidirectional single stage DC-AC converter is highly suitable for integrating batteries and renewable sources to the grid or standalone AC load. In this paper, a novel bidirectional AC link micro inverter has been proposed which is constructed based on the principles of dual active bridge converter. The synthesis of sinusoidal output is achieved by applying new composite modulation schemes that utilizes fundamental modulation schemes used in dual active bridge converter. Outpuit rms power can be controlled by the sine PWM and the phase shift between the DC and AC bridges. The proposed converter and modulation scheme is analyzed and simulation in PSIM environment. Finally a prototype was built and the proposed converter was experimentally verified.