Abstract:
This paper presents a method to reduce the torque
ripple in an 8/6 4-phase switched reluctance motor. The proposed
scheme introduces a nonlinear modulating factor dependent on
the rotor position and magnitude of the phase currents. This
factor manipulates the currents in two adjacent phases during
commutation and reduces the torque ripple effectively. Unlike
conventionally available torque sharing functions (TSF), the
proposed method instantaneously modulates every phase current
obtained mathematically based on the other phase current in
order to maintain the net torque constant. The proposed method
requires minimal offline analysis and offers maximum possible
torque with minimal ripple. The method is simple and easy
to implement due to less computational burden. The proposed
algorithm is implemented using Matlab/Simulink software and
is also validated experimentally on a 0.6 hp 8/6 SRM using an
FPGA-based hardware setup developed in the laboratory. Typical
results are presented and compared with existing techniques. A
torque ripple of ≈ 8% has been achieved.
