Industrial Electronics
Javad Rahmanifard; Saeed Hasanzadeh
Abstract
This paper presents an Enhanced Model-Free Sliding Mode Control (EMFSMC) method tailored for the speed loop of a 12-slot/19-pole yokeless and segmented armature axial flux-switching permanent magnet (12S/19P YASA-AFFSSPM) motor, focusing on robustness against parameter perturbations. Traditional control ...
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This paper presents an Enhanced Model-Free Sliding Mode Control (EMFSMC) method tailored for the speed loop of a 12-slot/19-pole yokeless and segmented armature axial flux-switching permanent magnet (12S/19P YASA-AFFSSPM) motor, focusing on robustness against parameter perturbations. Traditional control techniques, such as Proportional-Integral (PI) control and Model-Free Sliding Mode Control (MFSMC), have shown limitations in handling the motor's nonlinear behavior and susceptibility to disturbances. The proposed EMFSMC algorithm optimizes speed loop performance by establishing a hyperlocal model of the YASA-AFFSSPM motor, which accounts for parameter variations. An improved double-power combinatorial reaching law is developed to enhance convergence rates during the sliding surface approach phase, while an Extended Sliding Mode Disturbance Observer (ESMDO) provides real-time monitoring of unknown disturbances affecting speed control. Simulation results demonstrate that the EMFSMC significantly accelerates the speed response time to approximately 0.015 seconds with minimal overshoot, compared to 0.04 seconds and a 12.5% overshoot with the MFSMC. Additionally, under sudden load conditions, the EMFSMC controller exhibits a speed drop of only 4 rpm, recovering to stability in about 0.01 seconds, while the MFSMC controller experiences a 9 rpm drop with a recovery time of 0.03 seconds. These findings confirm that the EMFSMC enhances the speed response rate and robustness of the speed loop, outperforming traditional control methodologies across various operating conditions.