Effects of Position Sensing Dynamics on Feedback Current Control of Permanent Magnet Synchronous Machines
Prerit Pramod, Zhe Zhang, Krishna MPK Namburi, Rakesh Mitra, Darren Qu · 2018
This paper discusses the effect of dynamics involved in position sensing, including time-delays caused by sensor magnetics, electrical transmission and A/D conversion of sensed signals, on the feedback current control of permanent magnet synchronous motor (PMSM) drives. Position sensing dynamics essentially result in the position measurement errors, which will degrade the steady-state and dynamical tracking performance of the current and torque of the drive system. A detailed analytical model capturing the impact of errors caused by position sensing dynamics as well as back-EMF position offset on the feedback current control system for PMSM drives, along with an effective compensation technique, are presented in this paper. The overall block diagram of the closed-loop current control system in the synchronous frame considering the position sensing related errors is also presented. The analysis is validated through numerous simulation and experimental results for the practical nonsalient-pole and salient-pole PMSMs.