Comparison of Bidirectional Quasi Z-Source- and Bidirectional Conventional Two-Stage-Inverter for Electric Traction System

This paper presents a comparative study between the bidirectional conventional two-stage inverter (Topology A) and the called bidirectional quasi-Z- source inverter (Topology B) for electric vehicle (EV) applications. The comparison is conducted in terms of the voltage gain, current ripple, the transient and the steady state performances, and the inverters efficiency. The modeling and the control design for both inverters are presented and discussed. Simulation investigations are conducted to verify the inverter. It is shown that the Topology B has a higher voltage gain than the Topology A for some small duty cycle. The results demonstrate that the transient and the steady state performances of Topology A are comparable with the ones of Topology B under the same operating conditions. However, the Topology B shows lower inductor current ripple than Topology A. The results prove that the Topology B shows higher efficiency than the conventional solution. With these observations, the Topology B proposes an attractive alternative for EV applications.