A direct DC bus voltage regulation of the variable voltage converter in the electric traction drive system

摘要

Electrification of vehicles has been gaining a transition in recent years since new fuel-economy and CO regulation standards became technical challenges. For HEVs and Plug-In HEVs, the electric traction drive system, which includes a motor drive, a generator drive, and a variable voltage converter (VVC), is an essential part. The existing control for the VVC has intrinsic performance limitations associated with the DC bus voltage control. If the converter output power suddenly changes significantly and the DC bus voltage becomes lower than an input voltage, the system becomes unstable causing a voltage oscillation. In this paper, a new DC bus voltage control strategy based on a direct output voltage control using the capacitor current, is proposed based on an interleaved bi-directional DC-DC converter.