This work aims to study different ancillary servicessuch as frequency support, rotor angle stability and voltagestability that can be provided to independent AC areas throughMulti-Terminal HVDC grid. An agent-based control scheme hasbeen suggested to support the frequency of the imbalanced ACarea using other intact areas during a disturbance. The frequencysupport is carried out through some agents/controller, wherethe objective of the agents is to reach a common value fora given state, i.e. frequency, using the local and neighbouringinformation. In this scheme, the concept of Adaptive Graph (AG)has been introduced to the consensus problem to deal with thelimitation of original scheme in considering the rated capacityof HVDC converters. In this case, the frequency consensus canbe reached to a new stable value by removing one or severalconverters from the communication graph when reaching ratedactive power capacity. In order to test the proposed scheme,a model of 7-terminal dc-grid and corresponding AC areas isdeveloped in real time simulator OPAL-RT. The results showthat the adaptive graph scheme improves the reliability of thesystem during distributed frequency support.
QC 20160129