摘要本次毕业设计是基于反电动势的航模电调的设计，设计中首先介绍了与航模电调设计密切相关的无刷直流电机，对其基本构造和工作原理做出了一定的阐明。随后对有位置传感器和无位置传感器控制之间的差异做出了对比，接着分析了无位置传感器种类繁多的控制理论。由于本次毕业设计检测方法选用的是反电动势检测法，所以重点分析了反电动势检测法，透彻的分析检测方法也有助于论文的推进和完善。69236

对于本次设计中运用到的换相策略、PWM调制方式等理论知识，都做出了详尽的解释说明，最终选择以MEGA8单片机为设计核心的设计框架，完成了本次毕业设计的硬件设计。硬件的设计主要包括逆变电路、电压信号检测电路和反电动势法过零检测电路。设计中采用了全桥逆变电路，比传统的N沟道逆变电路更具优势，准确度和效率也得到了大幅提高。设计中还加有过流和过压保护电路，保护电路不受外界因素的影响和破坏。

检测出转子的准确位置是本次毕业设计的重点和难点，设计中通过对虚拟中性点进行过零检测，从而得到反电势的过零点，通过软硬件的协同合作，完成了对航模准确高效的控制。

该论文中有图20幅，参考文献31篇。

毕业论文关键词:  反电动势法  无刷直流电机  过零检测  

The design of Model ESC based on Back-EMF

Abstract

The graduation project is based on the counter electromotive force of the ESC model aircraft design, the design introduces the brushless DC motor and ESC model aircraft design is closely related to its basic structure and working principle made certain to clarify. Subsequent differences with a position sensor and sensorless control to make a comparison between then analyzes the position sensorless control of a wide variety of theories. Because of this design detection method chosen is counter electromotive force detection method, it analyzes the counter electromotive force detection, thorough analysis and detection methods also help promote and improve the paper.

For this design applied to the commutation strategy, PWM modulation and other theoretical knowledge, we have made a detailed explanation, chose to MEGA8 microcontroller core design framework for the design, completion of this graduation design hardware design. The hardware design includes an inverter circuit, a voltage signal detection circuit and method of counter electromotive force zero crossing detection circuit. Design with a full-bridge inverter circuit than the conventional N-channel inverter circuit advantages, accuracy and efficiency has been greatly improved. Design also added overcurrent and overvoltage protection circuit, circuit protection against external factors and destruction.

Detect the exact position of the rotor is this graduation design emphasis and difficulty, design by virtual neutral zero-crossing detection, thereby obtaining BEMF zero-crossing point, through collaborative hardware and software, completed accurately and efficiently model aircraft control.

Key Word:  Back-EMF  Brushless DC motor  Zero-crossing detection  

目   录

摘  要 I

Abstract II

目   录 III

图清单 V

1 绪论 1

1.1 无刷直流电机发展现状 1

1.2 无刷直流电研究意义 1

1.3 无刷直流电动机的控制方法 2

1.4 本设计的研究内容