Induction Motor Performance Under Voltage Sag Type I, Type II, and Type III: Experimental Study

Mostly, short circuit faults are the primary source of voltage sags. When voltage sags subjected to motor, a large current drawn by the motor, a large torque, and a decrease in motor rotation speed. This paper, presents the result of the experimental investigation on induction motor performance in terms of current peak and motor rotation speed change. The influence of various sag characteristics in distinct magnitude and duration of single and double voltage sags on the current peak was investigated at the beginning and ending of voltage sags. The voltage sag effects of Type I, Type II, and Type III are investigated in terms of the motor rotation speed and current peak. A Shaffner Profline 2100 EMC was used for generating various characteristics of the voltage sag. Based on the result, higher current peaks occurred at the starting and ending of voltage sag, but the currents at the ending of voltage sag are higher compared with the sag starting instants. The duration of the single and double sags did not influence the current peaks. They were influenced by sag magnitude, and the current peaks get higher for deeper sag. Voltage sag in Type III leads to motor speed drops much larger than in two other types (Type I, and Type II). Even it can cause the motor to stop running if it is supplied by deeper voltage sags. The availability of a shunt capacitor installed on the motor can mitigate the effect of voltage sags on the motor's rotation speed loss.