Study of Online Monitoring Technology for Insulation Characteristics of High-voltage Water Pump Drive Motors
Measurement of insulation resistance is mandatory for pre-servicing motors of pump stations to determine whether the insulations meet the requirements of operation.Currently prevailing methods to measure insulation resistance mainly rely on manual testing with a megohmmeter,which is cumbersome and time-consuming.Aiming at achieving fast detection of motor winding insulation characteristics,the present work proposed a design of an online monitoring device.The device works by utilizing a high-voltage module to generate a voltage of DC 2500 V,realizing automatic switching of tap position according to resistance variation of measured insulation between 1 MΩand 10000 MΩvia a sampling module and a tap control unit,and obtaining motor-to-ground distributed capacitance value through time constant method.The designed online monitoring device was demonstrated by comparative test capable of achieving a resistance measurement ac-curacy within±5%over the full measurable range,and function of additionally measuring parameters such as absorption ratio,polarization index,and distributed capacitance,thereby meeting the requirements of motor insulation characteristics test.
high-voltage water pumpdrive motorinsulation characteristiconline monitoring