A sensorless closing control for an AC contactor based on a new armature displacement estimator

This paper presents a new approach to solve the contact bounce after contacts closing problem for prolonging the lifespan and improving operation reliability. Based on combining a armature displacement estimator (ADE) with a simple hysteresis controller, such that the coil-current difference between the ac electromagnetic contactor (abbreviated ac contactor) body and the estimator is minimized, the proposed method overcomes the installation of an armature displacement measuring mechanism is indispensable restrictions imposed by previously described closing control methodologies. By using the proposed algorithm, an efficient control configuration can be obtained to reduce bounce duration. Computer simulations, of the proposed method, illustrate lots of benefits that are provided by proposed sensorless closing control configuration.