电动自行车调速系统的设计毕业设计论文

论文题目：

电动自行车调速系统的设计

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摘要

随着科学技术的进步，人们生活水平得到普遍提高，人们对出行似乎也有了更高的要求,社会上相继出现了摩托车、小轿车等许多的燃油汽车，其排放的气体对城市空气造成严重污染。面对当今世界的发展需要和社会的舆论，一些城市通过制定相关法规来限制燃油汽车的使用，进而减轻汽车尾气对空气的污染。所以短距离绿色交通工具的研制已经逐渐成为当今世界的主流。

本文主要研究永磁无刷直流电机控制的电动自行车的调速系统，该调速系统主要从硬件的选择和设计、电路的设计和系统的程序设计等方面进行设计，该调速系统的基本原理是根据选择电动机的特性实施单向式开环PWM控制，并通过转速传感器测量转速，通过显示电路的控制，用八态数码管动态显示转速，通过软硬件的配合，实现整个系统的设计要求。本次设计的核心是永磁无刷直流电机的选择。永磁无刷直流电机的优势是该电动机用电子换向取代了机械换向，消除了传统电机的机械磨损同时增大调速范围。

关键词：8051单片机；永磁无刷直流电动机；脉宽调速系统；转速传感器

ABSTRACT

With the progress of science and technology，people's living standards have generally improved，people travel seems to have higher requirements，the community have appeared in motorcycles，cars and many other fuel cars，their emissions of gases causing serious urban air pollution，in the face of today's world development needs of society and public opinion，some of the city through the development of relevant laws and regulations to restrict the use of fuel vehicles to reduce pollution of the air．Therefore，the development of short-distance green transport has gradual become the mainstream of the world today．

This paper studies the electric bicycle speed control system of permanent magnet brushless DC motor control, the speed control system is mainly basic principles of design，the speed control system hardware selection and design，circuit design and system programming，etc．Select the motor according to the characteristics of the implementation of one-way open-loop PWM control and a speed sensor measuring speed by the display control circuit，with the eight-state digital dynamic display speed by hardware and software together to achieve the design requirements of the system．The core design is the choice of permanent magnet brushless DC motor．The advantages of permanent magnet brushless DC motor which is electronically commutated motors replace mechanical commutation，eliminates the traditional mechanical wear of the motor and a very wide speed range．

Keywords: 8051；permanent magnet brushless DC motor；PWM speed control systems；speed sensors

目录

1. 概述 (1)

1.1电动自行车的发展现状 (1)

1.2研究的目的和意义 (2)

1.3电动自行车对电机的基本要求 (2)

1.4无刷直流电动机在电动自行车上的应用 (3)

2. 硬件的选择和设计 (4)

2.1 单片机的选择和设计 (4)

2.2 A/D转换芯片的选择和设计 (6)

2.3电动机的选择和设计 (6)

2.4 稳压器的选择和设计 (8)

2.5转速传感器的选择和设计 (10)

2.6译码器的选择和设计 (11)

3. 电路设计 (13)

3.1电源电路的设计 (13)

3.2显示电路的设计 (14)

3.3控制电路的设计 (14)

3.4驱动电路的设计 (14)

4. 系统程序设计 (16)

4.1主程序框图 (16)

4.2 INT0中断服务程序 (17)

4.3子程序设计 (18)

5. 结束语 (21)

6. 致谢 (22)