Determination of the Best Closing Phase Angle for AC Contactor Based on Game Theory

Any contactor bounce is undesirable since this causes arcing which shortens the life of the contacts when contacts close. The rebounds and the closing speeds are different with the closing phase angle of the electromagnetic coil voltage switching on when contactors close. This paper discussed the determination of the best closing phase angle of the electromagnetic coil voltage switching on. Taking closing phase angle as optimization variable, the closing velocities of three phase contacts and armature as objectives, and taking moving velocities lower than their worst values as restrictions, the optimization model was established. Game theory was introduced and adopted to solve the multi-objectives optimization problem. Taking CJ20 AC contactor as an example, the best closing phase angle was determined by combing the calculating and testing results.