Si vs SiC Diodes: A Performance Study of Interleaved Boost Converters for PV Applications

Nowadays, homes, offices, and establishments are switching to grid-tied photovoltaic (PV) systems owing to the benefits they provide to the environment and long-term savings. Moreover, the government subsidies and extra income provided by selling the excess energy produced by the system provide even more incentives for the switch.

In residential applications of a PV system, the most common system setup involves the following components: the PV panel, a pre-regulator (dc-dc converter) that also provides MPPT functionality, an interleaved boost converter (IBC), and a voltage source inverter (VSI) to guarantee the output current quality. The IBC, compared to a standard boost converter, provides ripple cancellation by forcing a 180° phase shift operation between the two switching cells. However, due to the high input voltage from the panels, the system suffers from high reverse recovery loss in the high voltage class silicon (Si) diodes (DB) and commutating loss in the switches (SB). The authors of this paper propose that the use of silicon carbide (SiC) diodes in the IBC will eliminate this loss owing to the zero reverse recoveries of SiC diodes.