Abstract
In response to energy crisis, many countries have active research and development of alternative vehicles, such as hybrid electric vehicles. The objective of this thesis is to develop a driver for brushless dc motor which is integrated with an engine to form a hybrid electric scooter. A motor driver can be divided into two operation modes of which one is motor-mode and the other one is generator- mode. In this thesis, a bi-directional power converter has been designed to replace a motor driver. The proposed power converter can function as a motor driver and can drive the generator to act as a charger. With the proposed power converter, the hybrid electric scooter system can be cost down. Based on the design considerations, switching components are three in parallel for each arm. It can equalize current, lower current rating, and reduce the rate of temperature rise. In high power applications, layout is a major impact on current sharing among the three switching components. Thus, this thesis not only develops a motor driver for hybrid electric scooter, but investigates layout strategies for motor drivers. Experimental results have verified the feasibility and performance of the proposed motor driver.