DC Interconnect Technology

Grid segmentation avoids cascading and blackouts

Segmentation technology uses back-to-back HVDC converters, HVDC transmission lines, and/or HVAC ties converted to HVDC links to segment any large synchronous grid into a set of smaller asynchronously operated areas or sectors. The resultant segmented grid is more resilient in that it will be capable of avoiding cascading and blackouts. Large scale impacts of storms, solar radiation and electromagnetic pulse (EMP) events, malevolent acts, random disturbances and operating errors will be contained within individual asynchronous sectors, and hence cascading failures should no longer be of any concern. Moreover, intra-area disturbances can be better contained.

Expanded total transfer capability

Expanded total transfer capability (TTC) can be achieved using a vastly improved controllability of power flow and grid operation under normal and emergency conditions. The power flow control provided at each HVDC boundary eliminates many constraints on inter-area transfers, thus increasing TTC. This means less need for developing new ROWs to meet challenges such as access to distant renewable resources.

Enhanced market operation

Enhanced market operation results from better transmission investment planning and efficient scheduling of transmission services enabled by the controllability of inter-area power flows.

The DCI team has been refining the grid segmentation concept since 2001. A market-oriented dc-segmentation design and optimal scheduling algorithms were patented in 2004. Recent activities include preliminary evaluation of segmentation in the Greater Northeast region of the Eastern Interconnect and a more advanced assessment of segmentation in the Greater Northwest region of the Western Interconnect.

The DCI team is available to take on new segmentation evaluation assignments.