MVDC for enhanced utility scale distribution power delivery and control

The electrification of heat and transport along with significant increases in distributed energy resources pose challenges for distribution network operators (DNOs) as they evolve into distribution system operators (DSOs). Issues may include capacity constraints, voltage excursions, lower supply security and reduced power quality. A method of addressing these matters whilst unlocking capacity is therefore required. This paper will outline the case for the selective interconnection of grid supply points and primary substations via fully controllable power electronic links. This interconnection would form the basis of a ‘power levelling’ network to help alleviate the above concerns as an alternative to a conventional ‘more copper’ reinforcement strategy. Power flows for a conventional network will be benchmarked before assessing the potential capacity release created by delivering energy from multiple substations via controllable interconnection. Medium voltage direct current (MVDC) networks (operating in the range of 5–50 kV) represent a candidate technology for the proposed interconnection. The paper reviews current technology readiness level, international learning and relevant knowledge from other power sectors.