Variable Structure Control of BLDCM Based on Extended State Observer

A simplified model of BLDCM is designed on the basis of the analysis of the actual model and characteristics of VSC,neglecting some minor elements,treating current fluctuation because of the current commutating as a disturbance.Based on the simplified model,the continuous,accurate and robust variable structure controller having an extended state observer for BLDCM is presented.VSC is insensitive to turbulence which can depress influence of the disturbances to BLDCM.The extended state observer(ESO)has good performance which can evaluate the states of uncertain object and real-time quantities of the object's disturbance.The torque of BLDCM can be evaluated exactly by the extended state observer which increases the precision of control.The simulation illustrates that variable structure controller makes BLDCM less overshoot and quick velocity response which is insensitive to parameters of BLDCM,and has good depression of many disturbances.A TMS320LF2407A digital signal processor(DSP)is used to fully prove the flexibility of the control scheme in real time.