As an environmental protection vehicle, electric bicycle is widely used for its flexibility and moderate price. However, there always exist heavy starting current, poor accelerating ability, low battery life and controller damage in the electric bicycles. In order to resolve this problem, this article proposes the method of synchronous gear shifting to improve the vehicle's performance aiming at improving dynamic property and efficiency of the vehicle.The article introduces the electric bicycle's present development situation and bottleneck-dynamic shortage and power efficiency, then introduces the drive mode of the electric bicycle, and take deep analysis on the advantages and disadvantages of the drive modes, proposes the method of synchronous gear shifting to improve the vehicle's dynamic property and efficiency, and lucubrate on the efficiency of the synchronous gear shifting. To realize the function of synchronous gear shifting, the article lucubrate construction and operation principle of the BLDC, analyze mathematical model, and seek out the most suitable way of inhibiting torque ripples ,getting ready for the high quality of shifting gears.Finally, the article builds the experiment platform and realizes the gear shifting actions with the DSPIC33JF32MC204.The hardware sections are comprised of power circuit, inverter circuit, drive circuit and detection circuit. The software sections are comprised of initialize module, self- detection module,main drive module, protection module and additional module. Then modifies the shifting parameters through the practical cycling test,and realize the optimum control. |