Structural Design of DC MV Grids
Power electronics enables the control of the load flow in electrical networks. In order to benefit from load flow control, a meshed network structure is required, since only meshed networks offer alternative paths for load flow that can be optimally selected by the controller. Transmission networks are already meshed; HVDC technology is used here not only for power transmission over long distances, but also for controlling the load flow in the underlying AC transmission network.
AC distribution networks, on the other hand, have a radial structure. The question therefore arises whether DC distribution networks should be designed as meshed networks in order to benefit from the possibility of load flow control by DC/DC or AC/DC converters. The impuls statement will give an insight into a research project in which the design of the medium voltage DC distribution network was determined by an optimization algorithm. The algorithm looks for the optimal compromise between higher investment costs due to meshed structures and a better use of a given infrastructure due to load flow control.
An interesting result is that meshed structures allow load flow control on the one hand, but at the same time it limits the advantage of load flow control due to Kirchhoff’s law. The optimal structure therefore has a low meshing.
Prof. Albert Moser
(RWTH Aachen University, Director IAEW & FEN Research Campus)