Research On Six-phase Brushless Direct Current Motor Control System Applied In Electric Motorcycle

At present, the problems of the energy crisis and environment deterioration are compelling people to rediscover the new sustainable and less polluting energy. The application of electric vehicles is an effective measure to resolve the problems of exhaust emission and to help relieve petroleum crisis. With the development of modern industry and the progress of science and technology, the research of electric vehicles is getting attention by people and its application is popularizing gradually. As an important component of electric vehicles, the quality of motor controller is to determine the dynamic performance. Therefore, researching on control system has very important significance for the development and the application of electric vehicles.This paper mainly studies the control system of six-phase brushless direct current motor used in electric motorcycles. The main chip of control system is digital signal processor (DSP) which has good performance and high computation speed. Otherwise, MOSFET is used as power device. The paper has given related research, analysis, design and experiments of the control system.Firstly, the paper has given a brief introduction of the history of electric vehicles, and has described the situation of development of the electric vehicles'three important components and the related technique. On this basis, having combined with the performance requirements of the drive motor and controller used in electric motorcycles, the system has chosen six-phase brushless direct current motor as drive motor. Then, the paper has discussed the motor structure, mathematic model and control methods and decided the components and control strategy of the system.Secondly, the paper has designed hardware circuit, software program and human machine interface in detail, and has a particular analysis and discussion on some circuit modules and control algorithm.Finally, there has actual controller which has been made according the design of the control system. The paper has given the difficulties and solutions in debugging process. And at the end, the paper has provided correct waveforms presented in the control system.In this paper, we have done a lot of work about hardware debugging, software programming, load test and on-site commissioning, based on a 4KW six-phase brushless direct current motor. Experiments show that the control system has a good dynamic performance, and that the controller can completely meet the performance requirements of electric motorcycles.