Effects of Brush Shift on Performance and Experimental Verification of Direct Current Motors

In this paper, the effect of brush shifting method is examined to improve the performance of brushed DC motors used in automatic door systems. The brush angles were tested to reduce commutation problems caused by armature reaction and to enhance motor efficiency. In the experiments, the motor was operated under nominal load, and current waveforms obtained by shifting the brushes clockwise (CW) and counterclockwise (CCW) at 4° and 8° angles were analyzed. The results show that shifting the brushes 4° in the counterclockwise direction minimizes current ripple and significantly reduces arcing during commutation. This method offers an effective solution to increase motor efficiency and reduce energy losses.