High-speed de-excitation system for brushless synchronous machines

摘要

This study presents a novel high-speed de-excitation system for brushless synchronous machines, where the deexcitation time constant can reach values of several seconds. In these conditions, despite the proper operation of the protection system, the slow de-excitation time constant may produce severe damage in the event of an internal short circuit. With the proposed system, a rapid de-excitation is achieved by inserting a resistance in the field circuit, obtaining a response similar to that in machines with static excitation. This system has been validated through computer simulations and experimental laboratory tests.