三相无刷直流电机控制系统设计-图文(精)

广东工业大学

硕士学位论文

三相无刷直流电机控制系统设计 姓名:孙心华

申请学位级别:硕士 专业:电力电子与电力传动 指导教师:童怀 20080501 摘要 摘 要

三楣无刷直流电机是近年来迅速发展起来的一种新型电机,它剃用电子挨耀 代替机械换相,既具有直流电机的调速性能,又具有交流电机结构简单、运行可 靠、维护方便等优点,并且体积小、效率高,在许多领域已得到了广泛的运用。 本文首先介绍了三相无捌直流电机在国内外的发展及其控制系统的研究现 状,详细论述了三相永磁无刷直流电机的构成、运行原理、特性分析和其转子位 置信号的检测方法;然后设计了控制系统的硬件电路及相应软件,最后对设计的 控制系统进行调试并分析了影响系统可靠性的睽素及给毒了相应解决的方案。 根据控制系统的设计参数、成本及灵活性等各方面的要求,本控制系统设 计了以Atmega8L单片机及ECN30206集成驱动器为核心的硬件平台。Atmega8L 单片枫对蠢ECN30206构成豹功率驱动电路进行转速PID闭环控制、并定时采集电 流信号对电流进行过流保护及采用Max7219串行显示转速、电流、相关故障信息, 通过光电隔离对永磁无刷直流电机诸如转向等控制及接收外部信息,通过RS-485总线接蹬与外部其它系统交换信怠、对各种信息进行分析处理、协调各部分的工 作。

在软件方面编制了基于硬件平台的程序,协调硬件工作。本控制系统软件由 一个前意念系统努加两个中断服务子程序,前看台主程序豳对系统初始化模块、 转子转速计算及转速PID闭环控制组成,初始化模块主要对Atmega8L单片机三个 定时器T0、T1、T2,ADC转换器,通用串行口UART,输入输出I/O口的初始化, 系统初始化之后再对无刷直流电机转子转速进行计算,计算结果再与设定值进行 比较,将比较差值送PID控制器控制PWM的占空比来控制专用驱动控制器 ECN30206的VSP引脚电压输入,从而控制转速,达到闭环控制的目的,中断程序 主要惩来睾行中断接收上位枫发来的无刷直流电机转向及转速设定僮、定时中断 检测电流及显示转速值及相关故障。

本文所设计的无刷直流控制系统实现了电机的转向、转速闭环PID控制、各 种参数及故障的显示。本控制系统保护功能较完善,硬件结构简单,成本较低, 主控制部分、驱动部分及显示部分用户可以任意选择使用。

广东工业人学工学硕上学位论文

关键词:三相无刷直流电机; Atmega8L单片机; ECN30206集成驱动器;PID闭环控制

Abstract Ab stract

Three phase brushless DC motor(BLDCMwith permanent excitation,whose electrical commutator iS used to instead of mechanical,has not only the same good characteristics of speed control as traditional DC motor,but also the good characteristics of AC Motor such as structure simple,operation reliable, maintenance friendly.Brushless DC motor has set wide application due to its high power density,ease to control,high efficiency over wide speed range.

The paper firstly introduced the study status of permanent magnet brushless DC motor in home and abroad,and then discussed its structure,operation principles,

characteristics as well as its rotor position signal detection methods in detail;secondly, designed

the control system’S hardware and software accordingly;越last debugged the control system,analyzed the factors affecting the reliability of the system and gave the corresponding solutions.

According to the requirements of control system such as design parameters,cost and flexibility,this paper designed Atmega8L SCM and ECN30206integrated driver as the core hardware

platform.Atmega8L SCM posed rotation speed PID closed—loop control on the system and regularly collecting current signal for the current over—current protection;used the Max7219serial display the current,related to fault

information;controlled Permanent magnet brushless DC motor’S rotate direction and received external information,through the isolation of the photoelectric;exchanged information,analyzed and processed the various information,coordinated various parts working through the RS一485bus interface with other outside systems.

This paper compiled a program based on the hardware platform to coordination with the hardware.The software of the control system is comprised by one fore.and—aft platform main program and two interrupt service subprogram.The fore.and-a爨platform main program is made up by the system initialization module, the rotor speed computing and PID speed closed—loop control component.The system

广东工业人学工学硕士学位论文

initialization module mainly initializes the three timers,A/D converter,serial UART, I/O pins.After system initialization,the main program computes the BLDC’S rotor speed and compared to the set speed value and then it send the error to the PID contr01. The

PID controller will change the voltage of the ECN30206integrated driver’S VSP pins according to the duty cycle of

PWM.In this way the rotor speed was controlled accord with the user’s setting value.One of the interrupt subprogram mainly used to receive the control order from the external system,which composed of rotor direction, rotor speed value.The other is mainly used to detect the current and display the speed and related failures regularly.

In this paper,the brushless DC motor control system achieved the rotor direction, speed closed—loop PID control,and various parameters defect display.The control system has a perfect protection,simple hardware structure,lower cost.The main control section,driver section and display section can choose arbitrary by the user. Keywords:Three phase BLDC motor; Atmega8L micro-C; ECN30206integrated driver;PID closed-loop control

广东工业人学工学硕L学位论文 独创性声明

秉承学校严谨的学风与优良的科学道德,本人声明所呈交的论文是我个人在 导师的指导下进行的研究工作及取得的研究成果。尽我所知,除了文中特别加以 标注和致谢的地方外,论文中不包含其他人已经发表或撰写过的研究成果,不包 含本人或其他用途使用过的成果。与我一同工作的同志对本研究所做的任何贡献 均已在论文中作了明确的说明,并表示了谢意。

本学位论文成果是本人在广东工业大学读书期间在导师的指导下取得的,论 文成果归广东工业大学所有。

申请学位论文与资料若有不实之处,本人承担一切相关责任,特此声明。 l l

指导教师签字:翟.牝