Torque Ripple Suppression Control Considering Magnetic Saturation in Position Sensorless Control with Extended Induced Voltage for IPMSM

Several torque ripple suppression controls for interior permanent magnet synchronous motors have been explored due to undesired effects of torque ripple on mechanical systems, including increased vibration and noise. Two distinct controls exist for torque ripple suppression: a method utilizes a torque meter to measure the torque ripple and reduce it directly. Another method involves using a mathematical model to estimate the torque ripple and mitigate its effect. Additionally, position sensorless methods, such as extended induced voltage or adaptive control, have been proposed. However, research on torque ripple suppression control with position sensorless control remains limited. Then, this paper proposes a novel method to enhance position estimation accuracy using q-axis inductance estimation. Notably, the proposed method requires simple controller modification and pre-measurement data; it relies solely on pre-obtained data used in the torque ripple suppression control. Experimental results demonstrate that the proposed method achieves approximately a 40% reduction in 6th-order torque ripple.