摘要随着社会科技和经济的发展，.越来越多的人们喜欢航模，其功能也在逐步的完善。国内在1979年正式步入航模领域的世界级赛场，标志着我国在航模领域与一些发达国家的距离慢慢缩小。本文首先对无刷直流.电动机的基本知.识做了简.单概述，其工作效率高、体积小、重量轻、寿命长等优点决定其应用在航模领域的必然。简单介绍了无刷直流.电动机由电机、开关电路与传感器3部分构成的内部结构；以硬件与软件结合达到控制电机的工作原理；建立数学理论分析电机运行特性；指出无刷直.流.电动机两.种控.制方.法：有位置.传感.器控制.和无位.置传感.器.控制。通过论述比较两者.的优点与缺点，无位置传感器以其稳定性好、寿命长、工作效率极高等结构特点成为必然的选择。对研究课题的整体设计方案给出详细的介绍，重点说明无位置传感器控制方法的多种控制方案，以反电动势过零检测法为核心，进行对比分析。自主.设计了基.于反电.动势过.零点电调的.硬件.电路，其中.包括：电源电压控制.电路、电.流检..测电.路和、驱动电.路以及控.制电路.。同时.对软件的流程作.了进一步.设计，其中包括：启动策略的分析、调速信号控制设计、换相控制的研究以及过零事件的处理。39773
本次课题设计通过与8051单片机作对比，采用.ATmega8.单片机为.核心设计硬件.系统，因其具有高度集成化、方便可靠与稳定等特点。其研究重点是用反电动势的检测方法，完成过零的检测，从而完成对系统对换相的控制，通过单片机内部程序的设计来完成对PWM占空比的调节，从而决定电机速度的控制，最终实现高性能的航模电调控制。.
毕业论文关键词： 无刷.直流电.动机 反电动.势.法 过.零检.测
Abstract
With the social and economic development of science and technology, more and more people like model aircraft, its function also gradually improved. Formally entered China in 1979 aeromodelling, a world-class stadium, marking the field with some of the model aircraft from the developed countries gradually reduced. This article first brushless DC electric motor of the basic knowledge. Knowledge made simple single overview of its high efficiency, small size, light weight, long life and other advantages of model aircraft to determine its application in the field of necessity. A brief introduction to the internal structure of brushless DC motors from the motor, the switch circuit and sensor 3-part;. To combine hardware and software to control the motor works; mathematical theoretical motor operating characteristics;.. Pointed out that the brushless DC motor two kinds of control methods: there is no position sensor position control and sensor control. Compare both through discussion. The advantages and disadvantages, position sensor with its stability, long life, high efficiency and other structural features become an inevitable choice. The overall design of the research program are given in detail, highlighting various control schemes without position sensor control method to back-EMF zero crossing detection method as the core, were analyzed. Independent design based on back-EMF zero crossing ESC hardware circuit, including: The power supply voltage control circuit, the current detection circuit and test .., drive circuit and. control. circuit .. At the same time the software design process for a further, including: analysis, control design speed signal startup policy, in other research phase control and zero-cross event processing.
The problem with the 8051 design for comparison, use .ATmega8. Microcontroller core hardware design system, because of its highly integrated, easy, reliable and stable. Its research focus is back EMF detection methods, completed a detection of zero, thus completing the control system for commutation, through the design of the microcontroller internal procedures to complete the regulation of the PWM duty cycle to determine motor speed control, the ultimate realization of high-performance model aircraft ESC control. . ATmega8单片机反电动势法的航模电调的设计+电路图:http://www.youerw.com/zidonghua/lunwen_40444.html