A Direct Torque Control Scheme with Different Switching Schemes at Low and High Speeds for Open-end Winding BLDC Motor Drives

This article introduces a Direct Torque Control (DTC) strategy developed for open-end winding BLDC (OEW-BLDC) motors powered by two inverters. The scheme incorporates different switching strategies for low and high speed operating conditions. The suggested strategy utilizes the voltage space vectors generated through the combination of voltage vectors from individual inverters. In this paper, certain voltage vectors of this combination are designated as 'uncertain voltage space vectors' due to the variability in their positions. The development of the DTC strategy excludes 'uncertain voltage space vectors'. The validity of the suggested DTC strategy is confirmed by means of numerical simulations conducted on the MATLAB-Simulink platform. The proposed scheme is also validated by experiments on a laboratory prototype and the control algorithm is executed by employing a TMS320F28377S DSP.