Dynamic control of MVDC link embedded in distribution network: — Case study on ANGLE-DC

Distribution network operators are encountering varied challenges through restricted corridors for expansion, fault-level constrained by capacity increase, increased pressure on operational efficiency, and proliferation of distributed energy resources (DERs). This will in effect impose limitations in power-flow and voltage. Moreover, due to the vast installation of converter based DERs like photovoltaic, electric vehicles, an efficient approach is to minimize the AC to DC conversion so as to reduce the losses by enabling DC technologies in the distribution networks. To this end, this paper assess the performance of a 33 kV distribution network with a proposed medium voltage DC (MVDC) link between the island of Anglesey and the mainland in North Wales, UK. This project will be the first of its kind in Europe and will paves the way for a more integrated DC network for the future. Dynamic operation and control of the proposed MVDC link is tested through PSCAD/EMTDC simulations. Operation of the DC link under steady state and during a single-line-to-ground (SLG) fault was tested. Moreover, a dual control loop has been implemented to improve the operation of the proposed link under SLG fault.