Electromagnetic Characteristic Analysis of Permanent Magnet Synchronous Machine Considering Current Waveform According to Static Rotor Eccentricity

Abstract

In this study, we performed an electromagnetic characteristic analysis of a permanent magnet synchronous machine considering the current waveform based on static rotor eccentricity. First, the characteristics of the back electromotive force were analyzed through the no-load analysis of the analysis model according to static rotor eccentricity. Next, a dynamic analysis was performed through mathematical modeling of a permanent magnet synchronous motor and PWM method. The input current during operation was derived through the dynamic analysis, and the core loss analysis was performed using derived input current. The core loss analysis was performed using the case where the fundamental wave current was applied and the input current derived through the dynamic analysis, and the results were compared.

Study on Stator-Rotor Misalignment in Modular Permanent Magnet Synchronous Machines with Different Slot/Pole Combinations

“…Stator-rotor misalignment, which can be classified into static eccentricity or dynamic eccentricity depending on the dynamics of the misalignment [24,25], wears down the bearings since it generates vibration and pulsing forces on their structure [26,27] and can truncate the fault-tolerance capability of electrical machines. In addition, eccentricity affects the performance of several topologies in terms of the generation of radial forces in the rotor structure [27][28][29], cogging and ripple torque increase [24,30], input current harmonic distortion when the machine is fed with inverters [31], and back-emf unbalance [30].…”

“…Studies on eccentricity effects are particularly relevant in PM machines, as the magnets on the rotor can generate significantly high radial forces on the stator structure and the bearings [24], which can trigger a major fault. The impact of eccentricity on PMSMs with non-segmented stators has been covered in [25][26][27][29][30][31], focusing on quantifying and analyzing the effects on the electromagnetic performance of the machine. Particularly, Recent studies have approached the analysis of some of these uncertainties, giving insight into the effect of design parameters and dimensional tolerances on the machine performance [15,17,18].…”

“…Studies on eccentricity effects are particularly relevant in PM machines, as the magnets on the rotor can generate significantly high radial forces on the stator structure and the bearings [24], which can trigger a major fault. The impact of eccentricity on PMSMs with non-segmented stators has been covered in [25][26][27][29][30][31], focusing on quantifying and analyzing the effects on the electromagnetic performance of the machine. Particularly, [29] disclosed a crucial design tendency that can be included in the early stages of the machine design: the electromagnetic performance penalization due to eccentricity strongly depends on the machine slot-pole combination, becoming especially relevant as the slot count and pole count get closer.…”