Brushless DC Motor Speed Control System Based on FPGA Digital Hardware

In a traditional brushless DC motor controller,digital regulator like a proportional integral(PI) controller was implemented by software,which had some shortcomings including slow response speed and low reliability.This paper proposed a fully digital hardware designed scheme of BLDCM speed servo controller,which was verified and implemented on one-chip field programmable gate arrays Cyclone Ⅲ FPGA.Using luxuriant logic cells of FPGA and combined with the characteristics of signal detection and motor control,the hardware logical circuits of all motor control modules including PI regulator,filter,speed measurement,feed forward control,PWM generator and BLDCM switching were constructed in HDL.The control system has the advantages of quick dynamic response,small overshoot,little steady-state error,high reliability and flexibility.It realizes total digital control and has preferable application value in high performance speed or position servo system.Experimental results show that the system control period is within 40 μs and the controller possesses good dynamic and static performances.