Flatness-based feed-forward control of an HVDC power transmission network

An efficient and well-established technology for power transmission across long distances is high voltage direct current transmission (HVDC). However, HVDC is up to now almost completely limited to peer-to-peer connections or networks with peers situated closely to each other. This contribution introduces the flatness-based design of a feedforward control of tree-like, i.e. cycle-free, HVDC transmission networks comprising two or more converter stations. The resulting control concept allows a flexible determination of the power distribution within the network. Furthermore, effects like power losses and delays due to wave propagation, which are related especially to long transmission lines, can be easily taken into account. Numerical simulations for an example network are included to prove the value of the results.