Periodic learning suppression control of torque ripple utilizing system identification for permanent magnet synchronous motors

A novel suppression method of 6th-order torque ripple of permanent magnet synchronous motor without torque meter

“…• The flux-linkage and the inductance of PMSM are including a harmonic components. At first, the armature flux-linkage of PMSM in each phase φ u,v,w are shown in (1).…”

“…However, PMSM has the problem on torque ripple caused by the harmonic components in the flux-linkage and the inductance. The 6th-order torque ripple causes some problems such as vibration, noise, the uncomfortable ride comfort, mechanical resonance [1]. Several torque ripple suppression methods have been proposed; and they can be classified mainly into two types which are online and offline methods [2]- [10].…”

New Simple Torque‐Sensorless Torque Control for Quasi‐perfect Compensation of Sixth‐Harmonic Torque Ripple Due to Nonsinusoidal Distribution of Back EMF of PMSM

“…The basic principle common to various compensation methods is presented here as preparation for the creation of the specific compensation method for torque ripple [2][3][4][5][6][7][8][9][10][11][12]. When issuing the torque command τ * to a vector-controlled PMSM, the PMSM is assumed to generate torque τ.…”

“…Methods of generating a compensation signal are classified in terms of whether they need a torque sensor or other sensor in order to detect the signal equivalent to the torque ripple (below referred to as "sensorless") [5][6][7] or do not need such a sensor (below referred to as "sensor-using") [8][9][10][11][12].…”

“…Compensation of periodic torque included in the generated torque is traditionally performed by superimposing a torque command or a compensation signal suitable for the current command corresponding to the ripple [2][3][4]. When a current control system has suitable tracking with respect to the compensation signal, the desired compensation can be expected [5][6][7][8][9][10][11].…”