Power supply trip control for nuclear reactor

摘要

A control system for a trip coil (18) in a switchgear mechanism (10) controls the supply of electrical power to a process control device (14) and ensures de-energization of the trip coil shortly after the trip coil is energized. The trip coil is energized not by an independent dc source as in prior art, but from rectified power from a step down transformer (20) supplied from the switchgear output side. The transformer feeds a rectifier (22) which is connected to the trip coil (18) via a trip activation device (24, 26). The output of the rectifier can be monitored using an optical converter (32) to determine the ability of the control system to activate the trip coil and the condition of the power supplied to the process control device. The control device (14) may be a rod positioner in a pressurised water nuclear reactor.