A Double Bootstrap Gate Driving Scheme for HERIC Topology

Highly Efficient Reliable Inverter Concept (HERIC) inverter is a popular choice in transformerless solar photovoltaic (PV) systems. It comprises four 'high-side' (not connected to DC side ground directly) and two 'low-side' (connected to DC side ground directly) semiconductor switches. Pulse transformers or opto-coupler circuits when used to drive the high-side switches increase the size and cost of the driving circuit. In this paper, a double-bootstrap gate driving scheme for high-side switches is proposed and investigated. The scheme, which uses easily available high-side driver ICs, results in a cost-effective and simple driving scheme. The operation of proposed scheme is established using both simulations and experiments.