Fundamental frequency coupling between HVAC and HVDC lines in the Quebec-New England multiterminal system-comparison between field measurements and EMTDC simulations

Fundamental frequency coupling between HVAC and HVDC lines has been investigated through actual field measurements in the Quebec-New England multiterminal HVDC power system. These are the first field measurements which clearly exhibit the fundamental frequency coupling. The measurements covered the sections of interaction located along the Radisson-Des Cantons part (approximately 1120 km long) of the HVDC transmission line. In these sections, the distances between the AC and DC lines do not exceed 1.5 km. During the field measurements, the recorded fundamental frequency currents in the DC line ranged between 1.05 and 1.20 A RMS. An EMTDC computer model of the coupling phenomenon has been developed and validated based on these measurements. This article presents the computer model and the results of the validation