Abstract:
Direct flux and torque (DFTC) scheme is introduced
for switched reluctance motors (SRMs) to minimize the inherent
output torque ripples. In DTFC voltage vectors are chosen in
such a way that the stator flux is kept constant, making it very
sensitive to working condition. However, in SRM phases are
independently excited, resulting in a nonlinear flux trajectory.
In this paper, a new direct torque control (DTC) scheme is
proposed, where sector boundaries are redesigned, and
alternative optimized voltage vectors are selected. The proposed
control technique also makes stator flux less sensitive to the
working condition. This allows the phase to de-energize faster
than the conventional DFTC, along with achieving high
torque/ampere ratio with reduced ripples in torque. To show the
effectiveness of the proposed DTC scheme over the conventional
DTFC scheme simulation studies for the same operating
conditions is carried out using Matlab/Simulink environment.
