Speed Control Of Brushless DC Motor Using DSP And ADRC

Electric commutation circuit is used in Brushless Direct Current Motor (BLDCM) to replace mechanical commutation in DC motor, which solves the problems existing in traditional Direct Cunent motor. Due to the good electrical and mechanical properties, BLDCMs are widely used in high precision motion control systems.such as servo applications, rabotics etc. BLDCMs have a brilliant future.Speed control system of BLDCM is established based on TMS320LF2407A DSP in this paper. Main circuit, circuit of rotor position detection, current detection, speed detection and some hardware information of DSP are introduced . General process of software development, problems in software programming and its solution are introduced . Phase current detection strategy is discussed in depth, Non-commutation phase current is used as feedback in current control loop, the difference of two phase current detection circuits is compensated.Both PI and ADRC algorithms are implemented for BLDCM speed closed loop control system based on TMS320 LF2407A DSP in this paper. Two kinds of control algorithms are compared, Experimental results indicate that when load torque changed, ADRC possesses less remedy time, less speed fluctuation compared with conventional PI controller. When BLDCM system parameter changed, the performance of PI controller obviously becomes bad. While ADRC remain unchanged, ADRC controller has better robustness compared with traditional PI controller.