VVVF INVERTER MAIN CIRCUIT ERROR DETECTION AND PROTECTION DEVICE FOR RAILWAY VEHICLE

摘要

PURPOSE: An apparatus for detecting the abnormality of a main circuit of a VVVF inverter for a railway vehicle and protecting the main circuit is provided to prevent an accident due to defects by performing a protection operation for a short time. CONSTITUTION: A logic circuit unit (10) compares a preset voltage and a preset current with a voltage and a current via a power transformer and a current transformer. A sensing circuit unit (20) senses the voltage and the current which are compared with the preset voltage and the preset current. The sensing circuit unit is operated with the sensed voltage and current. An analog-to-digital signal converter (30) converts the voltage and the current into analog and digital signals. An interface unit connects a propulsion control device to a traction motor and a monitor of a driving room. [Reference numerals] (22) DC low voltage; (23) DC over voltage; (24) DC over current; (25) AC low voltage; (27) AC over current; (28) AC over load; (30) Analog/digital signal switching; (AA) MCB trip