Hierarchy and complexity in control of large offshore wind power plant clusters

The scope of this paper is to review the hierarchical control architectures for offshore wind power plants (OWPPs) described in the state-of-art literature. A typical WPP control architecture consist of three levels: local wind turbine control level, WPP control level and control of group of WPPs. With more and more OWPPs development in close proximity and integration with the grid, future trends are favourable for large OWPP cluster formations, resulting in the growing need to better outline and interpret the WPP control strategies and propose means to establish coordination between the WPPs within large OWPP clusters. Coordination is essential for large WPP clusters to ensure the variable and stochastic wind power production does not adversely impact the overall grid stability and fulfil the requirement at PCC with optimised operation. Additionally, the paper also highlights the complexities associated with the hierarchical and coordinated control of large OWPPs and recommends ways to address them.