Impact of silicon carbide devices in 2 MW DFIG based wind energy system

Abstract

Renewable energies are going through a major increment, mainly wind and photovoltaic energies, being market competitiveness the main driver for their massive penetration. As power converters are used to interface renewable energy systems with the utility grid, their optimization is crucial. For their superior conduction and switching capabilities, silicon carbide (SiC) semiconductors are considered for their use in the optimization of power electronics in doubly fed induction generator (DFIG) based wind energy systems (WES). Potential efficiency gain and volume reduction due to the use of SiC semiconductors are studied by simulation, explaining the models in detail. Commercial products are evaluated to calculate cooling systems (CS) and output filters volumes. The performance and volume of SiC converter is analyzed and compared to its Si counterpart, at different wind speeds and switching frequencies. A design for maximum efficiency and minimum CS volume, and another for minimum output filters volume without efficiency penalty are achieved. A switching frequency optimization is performed to obtain the minimum combined volume between the CS and output filter, still improving the Si converters efficiency at nominal wind speed conditions. The conclusion is that SiC semiconductors can improve the power converters efficiency and overall size in DFIG WES.