Stability Analysis of Deadbeat-Direct Torque and Flux Control for Permanent Magnet Synchronous Motor Drives with Respect to Parameter Variations

Abstract

This paper presents a stability analysis and dynamic characteristics investigation of deadbeat-direct torque and flux control (DB-DTFC) of interior permanent magnet synchronous motor (IPMSM) drives with respect to machine parameter variations. Since a DB-DTFC algorithm is developed based on a machine model and parameters, stability with respect to machine parameter variations should be evaluated. Among stability evaluation methods, an eigenvalue (EV) migration is used in this paper because both the stability and dynamic characteristics of a system can be investigated through EV migration. Since an IPMSM drive system is nonlinear, EV migration cannot be directly applied. Therefore, operating point models of DB-DTFC and CVC (current vector control) IPMSM drives are derived to obtain linearized models and to implement EV migration in this paper. Along with DB-DTFC, current vector control (CVC), one of the widely used control algorithms for motor drives, is applied and evaluated at the same operating conditions for performance comparison. For practical analysis, the US06 supplemental federal test procedure (SFTP), one of the dynamic automotive driving cycles, is transformed into torque and speed trajectories and the trajectories are used to investigate the EV migration of DB-DTFC and CVC IPMSM drives. In this paper, the stability and dynamic characteristics of DB-DTFC and CVC IPMSM drives are compared and evaluated through EV migrations with respect to machine parameter variations in simulation and experiment.

Permanent Magnet Synchronous Machines

“…This trend can be seen in this special issue as a majority of the papers deals with PM motors with an emphasis on motor control. Five of the fifteen contributions target renewable energy sources [2][3][4]9,10], whereas the rest are focused on electric motors, with most examining electric vehicles [1,[5][6][7][8][11][12][13][14][15]. Three of the papers address brushless DC (BLDC) motors [7,11,12].…”

“…Three of the papers address brushless DC (BLDC) motors [7,11,12]. Six of the contributions present work on motor control, with the work of all six being experimentally verified [1,[6][7][8]11,15]. One paper is focused on fault diagnosis for hydropower generators [2].…”

“…However, alternatives exist and novel magnets have been heavily researched. Almost all the papers in this special issue are based on NdFeB-magnets, as stated by the authors in references [10][11][12][13] or as assumed from the contents in references [1,[4][5][6][7][8][9]14,15]. However, paper [3] investigates a span of magnetic properties, which could fit any magnet material.…”

“…Both reference [6] and reference [15] investigate the stability of control methods with regards to machine parameter variations. In reference [15], the stability of deadbeat-direct torque and flux control is investigated with respect to parameter variations for interior PM synchronous motors. The behavior of the controller when the values for inductance and permanent magnet flux linkage varied, was studied using eigenvalue migration as a stability evaluation method.…”

“…This special issue contains the successful invited submissions [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] to a Special Issue of Energies on the subject area of "Permanent Magnet Synchronous Machines". Interest in permanent magnet (PM) synchronous machines is continuously increasing worldwide.…”