Protective circuit for a power pack for excitation or de-excitation of a superconduction coil system

摘要

A protective circuit for a power pack for exciting or de-exciting a superconducting system has a voltage monitoring circuit at the output of the power pack. A switch in parallel to the output of the power pack is closed by the voltage monitoring circuit as soon as output voltage exceeds a predetermined value in a direction opposite a supply voltage of the power pack. During a malfunction, the switch closes and conducts the current which is being driven by the superconducting coil system. The protective circuit can be utilized in devices such as superconducting magnets of a tomography apparatus.