High efficiency and high performance power converters and motor drives for hybrid vehicles and electric ship propulsion.

摘要

The dissertation focuses on the high efficiency and performance power converters and motor drives for emerging applications in hybrid (electric) vehicle and electric ship propulsion. It includes eight papers organized in three parts as described below.; The first part includes Papers 1 through 3. As (hybrid) electric vehicles tend to have larger electric motors, the high peak power leveling capability of ultracapacitor is needed. Usually this requires a dc-dc converter along with its heavy and costly inductor(s) rated for the peak power. This part of the dissertation has multiple inventions in energy storage systems and its motor drive integration, which eliminates the dc-dc converter throughout the full speed range. This reduces the energy loss and cost considerably.; The second part is the hybrid (cascaded) multilevel converter controls (Papers 4, 5, 6). The multilevel converters, particularly the hybrid versions, achieve exceptional power quality at high power. Therefore, it is a promising candidate for large vehicle propulsion such as a naval electric ship. In this part of the dissertation, various new hybrid converter controls with unprecedented flexibility and performance are contributed. They include a distributed control, a joint control with P-Q compensation and edge shifting (single dc-source operation), operating limits analysis and dynamically changing do ratio control.; The third part is multiphase (more than 3-phases) converter/motor drives (Papers 7, 8). Featuring higher power density and fault tolerance, these drives offer a more compact and reliable option for electric vehicles and ships. This dissertation contributes several original discoveries and controls for a 5-phase VSI drive; new multiphase space vector modulation and optimal torque ripple control; the integration of the multilevel with multiphase topology; and the application of direct torque control to the 5-phase motor.