基于STC89C52单片机无刷直流电动机控制系统设计

摘要

电动机作为机电能量的转换装置,其应用范围已遍及国民经济的各个领域以及人们的日常生活之中。传统的直流电动机均采用电刷, 以机械方法进行换向, 存在着相对的机械摩擦, 由此带来了噪声、火花、无线电干扰以及寿命短等致命弱点, 制造成本高及维修困难等缺点,因而大大地限制了它的应用范围。永磁无刷直流电动机是近年随着电力电子器件及新型永磁材料发展而迅速成熟起来的一种新型机电一体化电机，它具有以下特点: 1．无刷直流电动机的转子采用高磁能积的稀土磁钢作为转子磁钢, 其转动惯量比鼠笼转子要小, 所以对于给定的转矩能够响应得更快, 控制特性更好。 2．无刷直流电动机的效率比感应电动机高。因为在感应电机运行时, 转子上不会产生铜损和铁损。 3．在相同容量下, 无刷直流电动机的体积相对要比感应电机小, 重量轻。 4．无刷直流电机的噪音小。 5．无刷直流电机调速方便, 灵活, 范围广。

在分析无刷直流电动机（BLDCM）数学模型的基础之上，提出了一种新型的无刷直流电机控制系统建模仿真方法。在Matlab/Simulink环境之下，利用无刷电机

关键词：无刷直流电动机；电刷；换向器；单片机

I

Abstract

Motor as electromechanical energy conversion devices, and their use has spread invarious fields of national economy and people in their daily life. Traditional DC motor brushes, mechanical method of commutation, there is a relatively mechanical friction, which bring about the fatal weakness of noise, sparks, radio interference, and short life, manufacturing high cost and maintenance difficulties and shortcomings. thus greatly limiting its scope of application. The permanent magnet brushless DC motor is rapidly maturing in recent years with the development of power electronic devices and new permanent magnetic materials up a new the mechatronics motor, it has the following characteristics:

1. The rotor of the brushless DC motor with high energy product rare earth magnet as the rotor magnet, the squirrel cage rotor inertia ratio is smaller, so for a given torque can respond faster to control features better. 2. The efficiency of the brushless DC motor is higher than the induction motor.Because the induction motor is running, the rotor does not produce the copper loss and iron loss. 3. In the same capacity, the volume of the brushless DC motor is relatively better than the induction motor is small, light weight. 4. Brushless DC motor noise. 5 Brushless DC motor speed convenient, flexible, and a wide range

Permanent magnet brushless DC motor controller structure has many forms, the initial complex analogue to the recently digital microcontroller as the core, but the new motor control ASIC, brushless DC motor speed control device design a great convenience, integrated analog control chip controlling function, the protection function, stable performance, simple system composed of the peripheral circuits required, and strong anti-jamming capability, especially suitable for volume controller, the performance requirements higher occasions. Advantages of a dedicated control chip of course, but often are expensive. In the occasion of some control accuracy is not high, you need to be able to have a working stability, price and relatively low-cost controller. This design is based on market demand.

Keywords:HCCI； Chemical Kinetics； Numerical Simulation； DME；

II

目录

摘要................................................................................................................................................... I Abstract ............................................................................................................................................ II 1设计任务和要求 ............................................................................................................................ 1

1.1 设计要求 ............................................................................................................................ 1 1.2 设计任务 ............................................................................................................................ 1 2系统组成原理 ................................................................................................................................ 3

2.1无刷电动机的基本结构 ..................................................................................................... 3 2.2直流无刷电机的换向原理 ................................................................................................. 3 2.3 单片机控制最小系统 ........................................................................................................ 6 2.4光耦隔离电路 ..................................................................................................................... 7 2.5 滤波电路和限幅电路 ........................................................................................................ 8 2.6 保护电路 ............................................................................................................................ 9 2.7 主电路设计 ........................................................................................................................ 9 2.8 总控制电路设计 ................................................................................................................ 9 2.9系统原理框图 ................................................................................................................... 10 3控制算法与系统软件设计 .......................................................................................................... 10

3.1转速控制器结构参数设计 ............................................................................................... 10 3.2电流控制器结构参数设计 ............................................................................................... 11 3.3采样周期选择 ................................................................................................................... 11 3.4控制算法和运算流程图 .................................................................................................. 11

3.4.1算法思路及初始化简述 ........................................................................................ 11 3.4.2运算流程图 ............................................................................................................ 13 3.5系统软件设计 ................................................................................................................... 14

3.5.1系统初始化程序模块 ............................................................................................ 14 3.5.2主程序模块 ............................................................................................................ 14 3.5.3编码脉冲—中断服务程序模块 ............................................................................ 15 3.5.4速度环采样和调节控制模块 ................................................................................ 16 3.5.5电流环采样和调节控制模块 ................................................................................ 17

4仿真（实验）结果分析 .............................................................................................................. 18

4.1 换向逻辑控制模块 .......................................................................................................... 20 4.2 控制器和控制电平转换及PWM发生环节设计 .......................................................... 25 4.3换相逻辑控制模块 ........................................................................................................... 27 5总结.............................................................................................................................................. 28 参考文献 ......................................................................................................................................... 29 附录I系统原理图 ......................................................................................................................... 29

1设计任务和要求

1.1 设计要求

设计一个以AT89C51单片机为控制核心的无刷直流电机调速系统。系统包括速度设定、速度显示、速度测量、速度控制、正反转控制、声光报警等。主电路采用MOSFET三相逆变桥，换向电路可以采用电机专用芯片。已知无刷直流电动机额定数据为60W/24V，调速范围30～3000r/min，采用霍尔位置传感器。

1.2 设计任务

本课题总的设计任务如下：

（1）完成系统理论与仿真分析

1）进行系统参数计算，完成转速、电流调节器的结构和参数设计； 2）利用Matlab/Simulink建立系统的仿真模型，对整个调速系统的动态性能（给定输入的跟随性能和负载与电网电压扰动下的抗扰性能）进行仿真分析。

（2）完成系统电气原理图的设计（包括电路原理图设计、参数计算、元器件选型）

1）主电路的设计； 2）单片机控制电路的设计 a. 单片机基本系统； b. A/D接口电路；

c. 编码器脉冲输入接口电路；

1