Performance improvement based on adaptive
commutation strategy for switched reluctance
motors using direct torque control
Fahad Al-Amyal a,
*, Mahmoud Hamouda a,b
, La´szlo´ Sza´mel a
aBudapest University of Technology and Economics, Department of Electric Power Engineering, Egry Jo´zsef utca 18,
H-1111 Budapest, Hungary
bElectrical Engineering Department, Faculty of Engineering, Mansoura University, Mansoura 35516, Egypt
Received 10 November 2021; revised 12 January 2022; accepted 13 February 2022
Available online 25 February 2022
KEYWORDS
Switched Reluctance
Motors;
Direct Torque Control;
Torque Profile Improvement;
Adaptive Commutation
Abstract This research presents an improved direct instantaneous torque controller (DITC) for
switched reluctance motors (SRMs). It incorporates a novel adaptive real-time commutation mechanism. The proposed method can effectively enhance the torque profile and efficiency of the
machine by proper real-time adjustment of both the turn-on and the turn-off angles. First, an initial
value of the turn-on angle is selected to achieve the highest torque generation capability. Then, with
a real-time adjustment around the pre-selected initial angle, the instantaneous torque error can be
further compensated. Hence, the torque ripple is minimized.
Regarding the turn-off angle, an initial value is selected to satisfy the minimum required conduction angle of SRM. Then, this value is continuously adjusted at each electrical cycle by utilizing a
phase current detector to force the outgoing phase current to decay to a less effective value before
the negative slope of the inductance profile. Therefore, this prevents serious negative torque generation. The proposed strategy fully utilizes the torque generation capability of the motor with a minimized torque ripple, besides the phase currents, are generated in optimal conduction range to
enhance the motor efficiency. The simulations and experiments have been carried out on a 3-
phase 750 W 12/8 SRM to validate the proposed method’s feasibility and effectiveness.
2022 THE AUTHORS. Published by Elsevier BV on behalf of Faculty of Engineering, Alexandria
University This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/
licenses/by-nc-nd/4.0