【作者】 刘铮；

【导师】 李醒飞；

【作者基本信息】 天津大学 ， 测试计量技术及仪器， 2007， 硕士

【摘要】 电动自行车因结构简单、轻便、易维护等突出优点而受到人们的普遍欢迎,市场需求量越来越大。无刷直流电机的控制是电动自行车的关键技术,由于成本的限制,目前市场上的多数无刷直流电机控制器存在诸多问题。本文的目的就是解决其中的关键技术问题,设计一款适合市场需求的低成本、可靠性好、功能齐全的电动自行车无刷直流电机控制器。本文从无刷直流电机的结构和工作原理出发,详细阐述了无刷直流电机在导通、续流和换相三种不同状态下的电压方程以及无刷直流电机的转矩特性与其动态数学模型,进而对电动自行车的性能作了深刻地分析,论述了电动自行车的电磁转矩的影响因素。论文以可编程片上系统(PSoC)CY8C24423作为控制系统的主控芯片,采用分立元件组成无刷电机的驱动电路,大大降低了产品的成本。文中详细阐述了功率MOSFET的特性、热损耗的原因及其驱动电路,浮动驱动部分通过比较使用低成本、易实现的自举法,论文还对电机位置信号、转把速度信号等各种信号检测电路以及PSoC的硬件电路配置方法作了描述。在软件设计部分本文根据市场需求,提出了软件设计方案,利用PSoC的特点合理搭配了各功能模块,规划了无刷直流电机控制系统的程序结构、流程,介绍了无刷直流电机的电子换相、电源电压监视等部分程序的设计流程以及编写PSoC程序时的注意事项。最后,以额定电压36V、额定功率250W的电机为样机,对控制器的性能和各项功能进行了严格的测试,给出了测试的图形、数据和结果,测试表明,该控制器可靠性好,成本低,符合产品的开发要求。更多还原

【Abstract】 The electric bicycles are popular more and more for their simple structure, portable, easy to maintain and other outstanding advantages, the market demand is growing. The control of Brushless DC motor (BLDCM) is the key technology for electric bicycles. Due to cost constraints, at present, many of BLDCM controllers are plagued with problems. The objectives of this study are to settle the key technical issues, and design a BLDCM controller for electric bicycles to meet the needs of low-cost, high reliability and complete function.Based on the structure and working principle of BLDCM, the voltage equations of BLDCM in conduction, freewheeling and commutation state are presented. After that, the torque characteristics and dynamic mathematical model of BLDCM are also introduced. On this basis, the thesis has made a profound analysis of electric bicycles’performance, and discussed the influencing factor of the electromagnetic torque.Programmable System on Chip (PSoC) CY8C24423 is used as the main controlling chip of the system, and the drive circuit is composed of discrete components, so the cost of the product is greatly reduced. This thesis also discusses the characteristics of the power MOSFET and its drive circuit. A method based on bootstrapping is used in the floating drive circuit for its low cost and easy to achieve. The detection circuits of BLDCM position signal and speed signal are described with PSoC hardware configuration method.In software part, according to the market demand, a program is presented. Based on the characteristics of PSoC, the functional modules and the main procedure structure of the control system are arranged. In the details, the electronic commutation, power monitoring and some other procedures are introduced.Finally, the motor with a rated voltage of 36V, rated power of 250W is selected as prototype to test the performance and functions of the controller, the graphics and data of the test results indicate that this controller can satisfy the needs of the market with low cost and good reliability.更多还原