Ocean testing of Wave Energy Converter (WEC) prototypes is necessary to facilitate commercial WEC development. The Ocean Sentinel Instrumentation Buoy, completed in August 2012, provides a stand-alone load for WEC prototypes during ocean testing. The first part of this work was to develop the power conversion and data acquisition equipment installed on board the Ocean Sentinel that is used to test WECs. The functionality of this equipment was demonstrated during August-October 2012 ocean testing of the half-scale WET-NZ wave energy converter. WET-NZ is an acronym for "Wave Energy Technology-New Zealand". The second part of this work was to develop a maximum power point tracking (MPPT) algorithm that can automatically track optimum control settings of WECs as sea conditions change. During the WET-NZ tests, a cycling MPPT algorithm was developed that provided more effective tracking of the optimum WET-NZ control input than was possible with standard perturb and observe MPPT algorithms. The effectiveness of the cycling MPPT algorithm was verified later during more systematic testing of MPPT algorithms using a WEC emulator, developed as part of this project, to simulate WEC operation.