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As the world pays more attention on the issues of energy and environmental problems, electric transportation industry develops rapidly. As the most convenient and flexible short-distance tool for the green traffic transportation, electric bicycle is more preferred. Therefore the development of electric bicycle industry has significant social and considerable economic benefit.At present, DC drive system is widely adopted by the electric bicycle in the domestic market. Electric bicycle drive system can be divided into two parts: wheel motor and controller. As the core component, the controller will influence the performance of the electric bicycle directly. Some inherent limitations of DC drive system, such as the commutation torque ripple caused by low accuracy, low positioning accuracy, smoothness sent etc, cause a lot of difficult problems to electric bicycle. Although people have done some improvement in the control strategy, but problems remain. Considering difficulties mentioned above, based on the study about permanent magnet synchronous wheel motors, an AC servo controller is developed.Firstly, through researching the function of the electric bicycle, the paper designed the general electrical scheme for AC electric bicycle. Under the guidance of general electric scheme, hardware circuit is designed including circuit principle design and PCB production. During the whole process of circuit production, each key circuit module and component is tested many times and carefully selected.Secondly, after study on various operation conditions, the paper formulated five operation conditions: start, speed operation, taxiing deceleration, braking deceleration, downhill speed restriction. For each condition, upper NC instructions and flow chart of functions are exploited.Finally, a lot of experiments were did including the rationality of the current sensor test, the dead zone test, delay test, the temperature rise test, various functional signal testing and driving test, experimental results show that the controller long time running effect is good.
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