Research And Design Of Electric Bicycle Controller

In the era of green and sustainable development, electric bicycles are experiencing rapid development and generate great economic prospects for the advantages of environmentally friendly, convenient in short ways, low prices and so on. PMSM(Permanent Magnetics synchronous Motor) under vector control is leading a new wave of electric bicycle technology upgrade which aims to provide better user experience.The paper analyzes electric bicycle controller based on the requirements of control performance and cost reduction. Firstly, the paper presents the mathematical model of PMSM under the coordinates of ABC and dq and makes analysis of angle compensation to the Integration Simulink Module. In the experimental stage, there finished the drive of PM BLDCM(Permanent Magnetics Brushless DC Motor)based on six-step control. Meanwhile, for the feedback of location and current required under motor vector control, the paper discusses about advantages and disadvantages of sampling scheme without sensor. Based on the comparison, it is decided to apply the technology of low-resolution subdividing hall sector and current reconstruction to the drive system design of electric bicycles with PMSM, which has lower cost. Secondly, the paper discusses three kinds of algorithm principle on hall location estimation and analyzes the effect of control under different working conditions of electric bicycles. Thirdly, for the aspect of current feedback, the paper makes comparison of traditional control schemes namely current sampling with the technology of current reconstruction with constantan wire and elaborated the principle of current sampling with three resistances or single resistance. The paper also discusses key technologies and basic hardware requirements of single-resistance current sampling. For the low-end chip, the way of cycle maintains is used to reach current reconstruction. Fourthly, the paper elaborates the principle of PWM pulse phase shift within cycle time of single-resistance current sampling in detail. On the basic of analyzing and summarizing common ways of pulse phase shift, the experimenter reduced the complexity of the algorithm to a certain extent by simplifying classification algorithm of current. On the basic of cost reduction, the experimenter finished the hardware design including isolated and non-isolated switching power supply and drive circuit of MOSFET, and so on. After building Saber simulations, the experimental test is finished. Taking consideration of the features of Nu Micro M058, the experimenter finished the development of software based on the assistance of hardware. Finally, the experimenter tested the overall controller of the electric bicycle and test results verified that the PMSM controller for electric bicycle can meet the requirement of low cost and high performance.