A Dual-Phase Output 4-Leg Inverter with Active Decoupling and Integrated Power Optimizer for Off-Grid Applications

Abstract

This paper presents an active decoupling technique for a dual phase output inverter with an integrated power optimizer for off-grid applications. The proposed method employs a half bridge with passive elements (L-C) to balance the output and actively compensate for twice the frequency power ripple in the dc-link, The closed loop control adjusts for varying load conditions. Further, an integrated power optimizer (PO) provides interface of solar-pv and battery to the dc-link, The PO stage (half bridge) is controlled such that maximum power point tracking (MPPT) is achieved for the connected pv-array and independent charge/discharge functions of the battery. Simulation and experimental results verify the performance of the proposed technique under balanced, unbalanced load, non-linear conditions as well as fault condition.