Instantaneous torque error compensation based online torque sharing function for Switched reluctance Machines

Abstract

An online torque sharing function (TSF) with instantaneous torque error compensation method for switched reluctance machines is proposed to maintain a minimized ripple operation. The proposed method adjusts the shared torque between the phases based on instantaneous torque error different than the existing TSF methods formulated with a mathematical expression. The objective of this approach is to benefit from the outgoing phase torque as it has slow current dynamics due to the high inductance. Also, the incoming phase is turned on as soon as it can generate positive torque. During this process, the total torque is estimated instantaneously using lookup tables, and a correction current is calculated and injected into the incoming phase reference current as the inductance is low and current dynamics are fast. This way, the torque ripple is reduced for a wide speed range. Compared to the conventional linear, sinusoidal, exponential, and cubic TSFs, better torque ripple performance is obtained.