Instantaneous Current Profile Control for Flat Torque of Switched Reluctance Motors

Abstract

This paper presents a new instantaneous current control to obtain an instantaneously flat torque waveform with smaller torque ripples of switched reluctance motors (SRMs). The proposed current control is based on table lookup. By geometric insights for the machine and finite element method based analysis, ideal current profiles for the flat torque are generated. Some simulation results are presented to demonstrate the validity of the proposed control, which are verified by experiment.

Torque ripple reduction of SRM by optimization of current reference

“…For SRMs having fewer poles, such as the SRM considered herein, the validity of the method using the current reference, such as that shown in Fig. 5, has been reported [1]. This current reference is the ideal shape for instantaneously flat output torque.…”

“…Assuming that the magnetic circuit of the SRM has the linear property, then the torque generated by the SRM can be expressed as follows: (1) where L a , L b , and L c are phase winding inductances, and i a , i b , and i c are the currents in the phase windings [2].…”

“…4(a) through 4(c). Many of the previous methods of torque ripple reduction are current control schemes using hysteresis control with this three-level voltage [1][3]- [5]. For SRMs having fewer poles, such as the SRM considered herein, the validity of the method using the current reference, such as that shown in Fig.…”

New Drive Circuit for Reducing the Switching Current Ripples in Switched Reluctance Motors

“…With methods of the second group, SRM structure remains unchanged; instead, stator current waveforms are controlled so that instantaneous torque is kept constant [5][6][7][8][9][10][11][12][13][14][15][16][17][18]. By realizing such stator current waveforms, one can compensate for nonlinearity of current and torque characteristics with respect to rotor position and rotation speed.…”

Torque ripple minimization of switched reluctance motors by controlling the phase currents during commutation

“…The modes are defined as follow, and the switching scheme is shown inFigures 6(a)-(c). Many of the previous methods of torque ripple minimization are current control schemes with this three-level voltage[8][9][10]. Three voltage modes of drive circuit…”