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To be a competitive supply of renewable energy, the power capture performance of ocean wave energy converters must improve. This requires that wave energy converter designers identify and invest resources to develop devices that exhibit a strong Technology Performance Level early in the development process. We contend that completing this identification process at the conceptual design stage requires a generalized method to establish the power capture upper bound for any given wave energy converter architecture. This upper bound must reflect simultaneous implementation of both optimal geometry control and power take-off force control – components known to be essential to optimizing performance but difficult to envision for complex WEC architectures. In this work, we develop and demonstrate a procedure, built on the mechanical circuit framework, to identify this upper bound for a self-reacting point absorber with an inertial modulation mechanism performing the geometry control. We illustrate how the analytical procedure generates generic design guidance, required to achieve the bound, without committing to a specific technology. We follow by formally introducing a new technology into the wave energy community, the inerter, capable of implementing the design guidance to enact the required geometry control. Finally, we apply the analytics within a numerical case study of a previously published wave energy converter configuration, and compare the power capture production of that device to one with equivalent hydrodynamics, but with the new geometry control feature set suggested by the new analytical procedure. Our analysis reveals the potential for a ten-fold increase in power capture even under stringent relative displacement constraints.

The design space for ocean wave energy converters is notable for its divergence. To facilitate convergence, and thereby support commercialization, we present a new simple method for analysis and comparison of alternative device architectures at an early stage of the design process. Using Thevenin's theorem, Falnes crafted an ingenious solution for the monochromatic optimal power capture of heaving point absorber devices by forming a mechanical impedance matching problem between the device and the power take-off. However, his solutions are limited by device architecture complexity. In this paper, we use the mechanical circuit framework to extend Falnes' method to form and solve the impedance matching problem and calculate the optimal power capture for converter architectures of arbitrary complexity. The new technique is first applied to reprove Falnes' findings and then to assess a complex converter architecture, proposed by Korde. This work also provides insight into a master-slave relationship between the geometry and power take-off force control problems that are inherent to converter design, and it reveals a hierarchy of distinct design objectives unbeknownst to Korde for his device. Finally, we show how application of the master-slave principle leads to the reduction in the dimensionality of the associated design space.