毕业论文--基于单片机的电动自行车调速系统设计.doc

基于单片机的电动自行车调速系统设计 PIC16C74单片机作为主控芯片，它不仅克服了有刷直流电机的噪音、换向火花等缺点，而且避免了有位置传感器直流无刷电机因位置传感器带来的不足；同时，它降低了制造和使用过程中的成本，提高了使用和维护的方便性，具有效率高、环保、经济和方便的特点以及具有良好运行性能和巨大的市场潜力。 关键词：电动自行车；位置传感器；直流无刷电动机；单片机控制 Based on the SCM system design speed electric bicycles Abstract:In the recent years，the motorbike has rapidly developed with the improving of living Chinese People. Because of air pollution of internal combustion engine the local governments of different cities in China come on a lot of rules of law to restrict the use of combustion engine and then to promote the environment protection. To replace the motorbike with a short green transportation has become some nations’ economic and social issue. This paper deals with an electric motor driven bike (EB) and its control stratagem. Without fail，EB 15 very helpful to environment protection. Nevertheless EB has its disadvantages，especially the too weak continuous run distance. Except the battery problem，the efficiency of the whole system 15 also one of the most important problems to be solved. A permanent brush-less and sensor-less DC motor and its control set are specially designed for this developed EB.A study on control stratagem and electronic resorts are given in this paper. A microchip PIC16C74 used as CPU and corresponding software developed by author 15 introduced in this control system. The experiments of the prototype show that the performance，including system efficiency，noise，spark，maintenance-free and its cost are obviously improved. It may be expected，that this EB driving system has really huge market potential. Key Words: Motor BikePosition Sensor；BLDC Motor；Microcomputer controlled 第1章 概述 1.1 电动自行车的意义及发展状况 1.1.1 电动自行车的意义 2章 电动自行车的研究 2.1 直流无刷电机原理简介 2.1.1 直流无刷电机的发展 直流无刷电机是在直流有刷电机的基础上发展起来的。由于直流有刷电机的换向器和电刷在电机高速运行时容易产生火花，引起火灾、爆炸等事故，因此许多环境限制了直流有刷电机的应用。随着科学技术的发展，开关型晶体管的研制成功，为直流电机的发展带来生机。经过不断的研究和实践，人们终于找到了用位置传感器和电子换向线路来替代直流有刷电机的机械换向装置。六十年代初出现了用霍尔元件传感器的直流无刷电机，七十年代初出现了比霍尔元件传感器灵敏度高许多倍的磁敏二极管换流的直流无刷电机。随着人们的不断努力，又发现了不用位置传感器，而依靠电机绕组在运