Adaptive droop based power sharing control algorithm for offshore multi-terminal VSC-HVDC transmission

Power sharing control and voltage regulation are considered as significant challenges in the development of large MT VSC-HVDC transmission grids, besides fault ride through and automatic restoration aspects. The main contribution of the work presented in this research is the proposal of a generic power sharing control algorithm. This algorithm is based on sharing the imported active power to the MT HVDC network among different AC grids based on desired sharing ratios, to fulfil active power requirements of the connected grids in order to achieve their own objectives, such as supporting the energy adequacy, increasing wind energy penetration and loss minimization. This algorithm is used as a supervisory control algorithm to integrate a number of offshore wind farms into various onshore AC grids.