Point absorber wave energy converters (WECs) closely placed in array hydrodynamically interact through wave radiation and diffraction. The power absorption by these WECs is optimised by altering the WEC dynamics through the control of the Power Take-Off (PTO). As the WEC dynamics are changed, the hydrodynamic interactions change as well. Therefore, the PTO control should be optimized taking all these interactions into account, referred to as centralized control. This work discusses the experimental design, implementation and testing of centralized controlled arrays of up to five 'WECfarm' heaving point absorber WECs, tested at the Coastal and Ocean Basin Ostend. A causal impedance matching Proportional (P) controller is used, approximating the complex conjugate of the intrinsic impedance of the WEC array in the peak wave frequency of the design sea state. Short-crested and long-crested irregular waves are used to obtain realistic operational and extreme sea conditions.
