Ocean wave and tidal current resources bear immense potential for generating electric power in near future. This article discusses an outline of generic system modeling for the purpose of grid interconnection studies. Due emphasis has been given on ocean energy's current state of the art and mathematical formulations are developed to fit the possible future needs. Ocean power schemes are approached with three different tiers of energy conversion: primary, secondary, and tertiary. Each of these stages, especially the primary and secondary conversion processes are elaborated further. A set of preliminary modeling and simulation exercise for a tidal current and a ocean wave system has been presented. Further work may include: model verification, reactive power management, and study of overall system control.