The Development Of Brushless Dc Motor Drive System For Light Electric Vehicl

Compared with the traditional internal combustion engine vehicle, Electric vehicle is the only kind of motor vehicles which has no pollution. In the past forty years, governments of the world to vigorously develop the electric vehicle industry, as a effective method to resolve the energy drying up and environment worsening. The brushless DC motor has widely used in electric vehicles in recent years. It not only has excellent speed characteristics of dc motor but also has the advantages of simple structure high operational reliability longer life.A drive system of the electrical lighter vehicle with the brushless DC machine is developed in the thesis. The system consists of a control unit based on a digital signal processor (DSP) and a drive module which combines a drive circuit, a brushless DC machine, and associated wheels. The motive power is delivered directly to the wheels without a power transmission system. The driving comments and the monitored signals between the modules and the control unit are communicated by the Controller Area Network (CAN) Bus. Each module can be controlled independently. By modifying the software of the system, the proposed drive system can be implemented in various electrical vehicles without changing circuit design.The developed system can be operated at forward, backward, and rotating motions. By limiting the armature current, the vehicle can be operated under the power saving mode. During there generative braking, the battery set is charged by the regenerative current. The experimental results show that the highest efficiency of the machine is80%with the motoring operation.