Design and control of a multilevel inverter for electric vehicles.

摘要

Typical AC induction motor drive systems in electric vehicles use full-amplitude pulse width modulation inverters. These have many drawbacks including the requirement of a cooling system, lack of integrated battery management, and often non-integrated and/or low-power charging. There is also an issue of safety with a permanently connected series battery pack, and motor winding insulation is degraded in this type of controller. Moreover, the size and mass of these inverters reduce available vehicle storage space. An ideal solution is to provide a small inverter for each battery, so that its charge can be maintained individually and a low-distortion sine wave can be applied to the motor. A battery charger is then intrinsic in this layout. This work presents the development and implementation of a such a multilevel inverter. Two separate designs are constructed, each including a master module and six slave modules. Results from driving a GM EV1 using the second design are presented. Hardware and software designs are attached, including PC interface code in 'C++' and algorithm simulation code in Python.