Performance comparison of IGBTS and SIC-MOSFET applied in photovoltaic inverters during reactive power injection

Abstract

The ac-grid power quality can be significantly affected by the impact of many small photovoltaic (PV) grid-connected inverters. There are many ways to improve the system stability, regarding voltage regulation. Some works in literature propose to use the multifunctional PV inverter to support reactive power to the grid. The main drawback of this solution is the increase of losses in the converter during this additional functionality. Therefore, this paper analyzes the power losses and temperature in the PV inverter semiconductors during reactive power injection. This analysis is made using four different IGBTs technologies and one SiC MOSFET. Simulations considering a 5kW three-phase PV inverter are performed with focus in the comparison between these five semiconductor devices.