Predictive Current Control for Switched Reluctance Motor Based on Local Linear Phase Voltage Model

Abstract

In this paper, a predictive phase current control (PCC) scheme based on a local linear phase voltage model for a switched reluctance motor is proposed. The current is controlled by regulating the average voltage through PWM, ensuring a fixed switching frequency. A linear model is proposed to approximate the relationship between the voltage and the current slope in a short period. By using the voltage and current slope information in the previous control cycle, the intercept and slope of the model can be identified online. In the previous control cycle, the phase voltage changes from zero to positive or negative DC-link voltage, and then the identified model is used to predict the average voltage required in the next PWM cycle for the actual current so as to accurately track its reference. The effectiveness of the proposed PCC was verified experimentally. The results demonstrate that the proposed control scheme can significantly reduce the current and torque ripples compared to hysteresis control with the same sampling rate. The proposed PCC is easy to implement, does not need to obtain the motor characteristics in advance and is not sensitive to the changes in characteristic parameters caused by motor aging, etc. It is relatively suitable for applications that need to accurately track the given current curve.

An Analytic Method of Segmented PWM Duty Cycle for Switched Reluctance Motor

“…X. Zhang also adopted the deadbeat current control method to improve the phase current control accuracy, which also has a good effect in suppressing current ripple [4]. In order to improve the current tracking performance, S. Q. Shen predicted the average voltage required for the actual current of the next cycle according to the voltage and current of the previous cycle [5]. S. K. Sahoo can track the given current at the fixed rotor position by iterative learning control of the voltage at the fixed rotor position [6], [7].…”

Torque-Enhanced Phase Current Detection Schemes for Multiphase Switched Reluctance Motors with Reduced Sensors

“…In recent decades, the switched reluctance motor (SRM) has drawn increasing attention in some applications such as the electric vehicle, due to its many merits such as high reliability, low cost, and wide operating range [1][2][3]. For SRMs, phase current detection plays a crucial role in phase current control such as hysteresis current control [4], PI current control [5], predictive current control [6,7], diagnosis of power converter [8,9], and most sensorless position estimation methods [10]. Conventionally, each phase of an SRM needs a hall effect sensor along with a signal-conditioning circuit and an analog-to-digital channel to detect its current, and thus current detection of a phase is completely independent of that of any other phase.…”