sensitivity analysis of ac coil contactor to voltage sags and enhancement of ride through capability
Voltage sags are among the most important power quality events due to their economic effect on all types of customers, especially industrial users. The normal device used for motor connections and disconnections is the contactor, and thus it is of importance to know what type of voltage sags will open the AC coil contactor or engage it. This information is very valuable not only to the contactor user but also to the designer and manufacturer. Normal contactors would open when voltage sag exists in its supply system. This paper shows the results obtained from thorough laboratory testing carried out on ac coil contactor considering various sag magnitudes durations and point on wave values. Simulation results with MATLAB 7.1 Simulator version are also presented. A cost effective ride through solution is also discussed to improve contactor immunity to voltage sags.
ac coil contactor voltage sag contactor ride through equipment sensitivity