Mercury Arc Valve Disturbances Experienced in the Sylmar HVDC Converter Station

Oscillographic records of the mercury arc valve disturbances experienced at the Sylmar Converter Station (the southern terminus of the Pacific Northwest-Southwest HVDC Intertie) are presented and discussed. The disturbances experienced include arc-throughs, arc-backs, consequential arc-backs and a new disturbance combination called a simultaneous arc-back. This presentation will provide a reference for mercury arc valve disturbance characteristics, and their effects on both the valve bridge outputs and the entire HVDC system.