Brushless Dc Motor Dual Closed-loop Control System

The brushless DC motor, with its small size, high efficiency, low noise, light weight and high reliability in the Rapid development modern society, widely used in apartment computer peripherals, office equipment, household appliances, electric vehicles and industrial control. The extensive use of brushless DC motor makes research it became necessary.Brushless DC motor is a nonlinear, multivariable, integrated system. Brushless DC motor on the terms of the current research is very active. Brushless DC motor control strategy is one of key technologies. Control method of the present study, such as single-loop control, open loop control, dual-loop control and three closed-loop control.In this paper, model EP2C5T144C8-FPGA chip, use the current speed control of double closed PI loop. Divided into the following main aspects:Introduces brushless DC motor structure, working principle and the basic principles of digital PID controller and its parameter selection;Analysis and selected the brushless DC motor control and current detection methods;In the software part, highlighted the commutation control module and dual closed loop control system;In the control analysis phase, focuses on the speed loop PI control, and integral separation limit case of the current loop integral PI control weakened, were determined by parameter selection method, parameters.Experimental results show that the text speed loop and current loop PI control is superior to PI control, dual-loop control of a single closed loop PI control is superior to PI control. The results can be concluded:Two closed-loop system effectively improve the system stability and improve the motor speed of the static and dynamic performance.