Experimental Investigation of ac contactor ride through capability during voltage sag

This paper presents the effect of voltage sags on different types of ac contactors. Based on recent testing standards and utilizing a modern industrial power corrupter, experiments were conducted at different sag magnitude, duration and point on wave. The predefined malfunction criterion is the unwanted disengagement of the main contacts. The experimental results show that different contactor has diverse level of ride through capability which depends on point on wave, magnitude and duration of the voltage sag. Experimental Investigation also shows that increasing sag initiation angle from 0° to 90° allows contactor immunity level to decease in term of sag magnitude.