Torque ripple minimization and speed control of switched reluctance motor drives using extremum-seeking PI controller

To improve the state-of-the-art control of a switched reluctance motor (SRM) drive, this research paper proposes and applies a novel approach for tweaking the parameters of the proportional-integral (PI) current controller using a multivariable sliding-mode extremum-seeking (MSES). The proposed MSES-PI current control approach uses a sliding-mode extremum-seeking optimizer to fine-tune the PI control gains to minimize a cost function defined by the feedback error term. As a result, the PI current controller exhibits robustness against disturbances and insensitivity to changes in SRM parameters, while remaining sensitive to tracking reference current inputs. In addition, this study proposes an innovative speed control strategy for SRM drives using an adaptive extremum-seeking PI speed controller (AES-PI). The proposed speed control utilizes a PI controller and a separate version of the extremum-seeking controller to enhance the step responsiveness of SRM drives. In particular, AES minimizes a cost function analogous to the one used to quantify the performance of the PI speed controller. Both simulation and experimental verification show that MSES-PI and AES-PI outperform traditional PI controllers. Through the utilization of ES to fine-tune the PI controller's settings, dynamic performance is enhanced, and torque ripple and speed oscillation are significantly suppressed.