CORE MONITOR OF ROTARY ELECTRIC MACHINE

摘要

PURPOSE: To detect impairment of an insulator with high reliability before considerable impairment occurs in a core of a rotating electric machine, by detecting a difference in voltage between adjacent parts of first and second shaft brushes and a frame. CONSTITUTION: A difference in a rotor shaft voltage between end parts 16 and 18 of a rotor shaft is measured by using spring biased shaft brushes 20 and 22. High impedance isolation differential amplifiers 24 and 26 are connected to the brushes 20 and 22 respectively. A differential amplifier 28 generates a difference in the rotor shaft voltage between the end parts 16 and 18 of the rotor shaft. This differential voltage is inputted to a computer 32 through the intermediary of an A/D converter 30. This computer 32 makes an alarm generated when a difference between the differential voltage at the present time point and that at the previous time point exceeds a prescribed value.