An Active Damping Control Method for the LLCL Filter-Based SiC MOSFET Grid-Connected Inverter in Vehicle-to-Grid Application

Research studies of vehicle-to-grid (V2G) are gaining more and more attention, because of its attractive features, such as, transferring bidirectional power between electric vehicles and grid, regulating grid voltage/frequency etc. This paper investigates the damping technique of the grid-connected inverter for a V2G application. As the silicon carbide (SiC) MOSFET has obvious advantages in high-power-density inverters with a high switching frequency, an LLCL filter-based SiC MOSFET inverter is designed to suppress the harmonics and increase the power density in this paper. By analyzing and comparing the suppression effects of four passive damping methods on the resonance peak of the LLCL filter, it is found that passive damping control strategy brings extra loss into the V2G system, and affects the performance of LLCL filter. An active damping control method is proposed to reduce losses and ensure better dynamic performance. The feasibility of the design scheme and performance are verified by simulations and experiments.