Effect of wave farm aggregation on power system stability

There is a large and varied range of wave energy technologies presently under development, in varying stages of progress from model scale to pre-commercial prototypes. Similarly to offshore wind farms, it is anticipated that when these wave energy converters (WECs) ultimately reach commercial stage, they will be implemented in a farm layout, in order to improve economic feasibility and power quality. Transmission System Operator (TSOs) carry out power system dynamic simulations in order to investigate the effect of renewable energy farms on the stability and reliability of the grid under varying operating conditions. A detailed dynamic model of each individual WEC in the wave farm would be complex and computationally intensive; therefore aggregating the wave energy farm into a smaller number of models may be desirable for the TSO. This paper describes the methodology for simulating arrays of WECs in a power systems simulation tool, and examines the effects of aggregation on the load flow studies and stability analysis of the farm. The methodology is validated using DIgSILENT Power Factory simulations.