Towards Canada’s Transcontinental Supergrid: AC/DC Transmission Merge Solutions

A major coordinated effort promoted to move clean electricity “freely from coast to coast” is related to Canada’s Transcontinental Supergrid interconnecting all its provinces through highest-quality power transmission. The proposed Canada’s Supergrid would enable and ensure reliability, resilience and energy security of each of the provincial transmission grids and the Transcontinental Supergrid as a whole. Supergrid presents the infrastructure for Canada’s emerging national electricity market. It is backed up by inter-regional scale wholesale experiences of the Australian National Electricity Market, European Internal Electricity Market and wholesale electricity markets administered by Regional Transmission Organizations in the U.S. For Transcontinental Supergrid planning, adjusted total transfer capability limits for interprovincial and international transmission paths are proposed to establish an interprovincial coast-to-coast transfer capability target. In Supergrid transmission planning, High Voltage Direct Current (HVDC) is seen as a key Supergrid segment leading in today’s AC/DC Transmission Merge. HVDC has demonstrated globally major improvements in its capabilities, increasingly needed to enhance the existing AC grid upgrade. HVDC multi-value makes it highly competitive technically and economically. High capacity, long-distance, controllable, multi-terminal HVDC technology is particularly valuable for transcontinental transmission across multiple jurisdictions. HVDC Back-to-Back (B2B) solutions for provincial interties and international interconnections present a compelling case for the Supergrid planning. A set of eight HVDC Voltage Source Converter (VSC)-based B2B stations, 4,860 MW in total, is proposed as a core Supergrid Solution to leverage prompt planning and deployment of Canada’s Supergrid.