Variable Speed Operation of Brushless Doubly-Fed Reluctance Machine Drive using Model Predictive Current Control Technique

In this project, to accomplish an accurate and fast drive control, Model Predictive Control (MPC) is considered as an effective control strategy nowadays. In MPC, the voltage vectors required for inverter control are evaluated considering the control objectives defined in terms of current or power or torque and flux. 

The optimal one is selected using an iterative prediction loop and applied in next control interval. This form of MPC is simple in implementation and shows appreciable dynamic performance but the steady state performance is compromised due to the limited availability of number of voltage vectors, especially in case of two-level voltage-source-inverter. 

The present article explores the viability of MPC approach for a new device like brushless doubly-fed reluctance machine drive considering its secondary current as the control variable. Moreover, to tackle the steady-state inferiority issue, the duty-cycle control concept is inducted. 

In comparison to Field Oriented Control (FOC), the proposed scheme offers straightforward solution for current control by replacing the inner current Proportional-Integral (PI) controllers and pulse-width modulator with an optimization-based model predictive current controller. The proposed system is simulated in MATLAB/Simulink.

Keywords: Field Oriented Control (FOC), Model Predictive Control (MPC), Direct Torque Control (DTC), Direct Power Control (DPC).