An improved equivalent-input-disturbance approach for PMSM drive with demagnetization fault

Area of Science:

• Electrical Engineering
• Control Systems
• Motor Drives

Background:

• Permanent magnet synchronous motors (PMSM) are vital in industrial applications requiring precise torque control.
• Permanent magnet (PM) demagnetization, caused by factors like high temperature, degrades PMSM performance and hinders accurate torque control.

Purpose of the Study:

• To develop an effective fault rejection method for PM demagnetization in PMSM drives.
• To enhance the precision of torque control in PMSM systems affected by demagnetization faults.

Main Methods:

• A system model incorporating demagnetization faults was constructed.
• An improved equivalent-input-disturbance (EID) approach was designed to reject demagnetization effects.
• An improved sliding-mode observer was utilized for faster and more accurate estimation of equivalent-input-demagnetization, outperforming conventional Luenberger observers.

Main Results:

• The proposed EID method effectively rejects the impact of PM demagnetization.
• The improved sliding-mode observer significantly enhances the speed and accuracy of fault estimation and rejection.
• Hardware-in-the-loop experiments demonstrated superior torque tracking accuracy compared to existing methods.

Conclusions:

• The improved EID approach offers a robust solution for addressing PM demagnetization faults in PMSM drives.
• This method significantly improves the accuracy and reliability of torque control in the presence of demagnetization.
• The study validates the effectiveness of the proposed technique through experimental comparisons.