SOFT STARTER OF THREE-PHASE INDUCTION MOTOR HAVING FUNCTION FOR MEASURING INSULATION RESISTANCE AND CONTROL METHOD THEREOF

摘要

The present invention relates to a soft starter of a three-phase induction motor having a function for measuring insulation resistance capable of, when a three-phase induction motor is not driven by a preset scheduler, measuring a current leakage by gradually increasing an applied voltage from a low voltage up to 500 V to measure insulation resistance, determining a state as a normal state if a calculated insulation resistance value is greater than or equal to a set value, and then flexibly operating the motor when a motor start signal is inputted, and more specifically, relates to a soft starter of a three-phase induction motor having a function for measuring insulation resistance which has a function of protecting a power device for measuring insulation resistance and winding a motor by gradually increasing the applied voltage from a low value up to 500 V for generating a current leakage, and a control method thereof. The present invention provides a soft starter of a three-phase induction motor having a function for measuring insulation resistance which can prevent a ground fault accident caused by dielectric breakdown of the three-phase induction motor by automatically performing an insulation resistance measurement work according to a schedule of the preset scheduler before the three-phase induction motor is operated by using the soft starter. The soft starter of a three-phase induction motor having a function for measuring insulation resistance comprises a voltage detecting unit, a power switching unit, a high voltage generating unit, an insulation resistance measuring unit, and a control unit.;COPYRIGHT KIPO 2017