摘要：本文分析了无传感器BLDC控制系统的工作原理，在此基础上进一步分析其控制方法。并针对相对成熟的反电动势法进行了深入分析，对该方案下基于DSPIC的硬件电路和软件方案进行了设计，给出了高速、低速两种情况下过零检测的方法。该方法克服了低速下无传感器BLDC难以检测零点问题，进一步拓宽了无刷直流电机的应用领域。本文很好的解决了无传感器BLDC控制系统的设计问题，具有十分重要的工程前景。

关键词：DSPIC无刷控制；反电势过零检测；无传感器控制；BLDC
Abstract: This paper analyzed the working principle of sensorless BLDC control principle and control method. Carried on the thorough analysis in view of the relatively mature method of back EMF, the scheme of hardware circuit and software scheme based on DSPIC was designed, gave two cases with zerocrossing detection the high speed, and low speed. The method can overcome the low speed sensorless BLDC difficult to detect zero problem, further expand the application field of brushless DC motor. In this paper, the solution to the design problem of sensorless BLDC control system, has important engineering prospect.

Key words: DSPIC brushless control; backEMF zerocrossing detection; sensorless control; BLDC