A control and protection system for an AC-DC conversion system for exchanging an electric power between two AC power systems. The AC-DC conversion system is composed of two power converters and two circuit breakers connected to the two AC power systems. Each of the power converters...http://www.google.ca/patents/US5715151?utm_source=gb-gplus-sharePatent US5715151 - Control and protection system for AC-DC conversion system
