Maximal electric power generation from varying ocean waves with LC-tuned reactive PTO force

TL;DR

This paper introduces an LC-tuned wave energy converter that maximizes electric power generation from ocean waves by resonating with wave frequencies, using a simple reactive PTO force design.

Contribution

It presents a novel LC-tuned WEC design with analytical tuning rules for optimal power absorption across variable wave frequencies.

Findings

Achieves maximal electric power generation through resonance tuning.

Provides analytical models for power absorption and generation.

Simulation confirms effectiveness and advantages of the proposed design.

Abstract

The reactive Power Take Off (PTO) force is the key to maximizing mechanical power absorption and electric power generation of Wave Energy Converters (WECs) from ocean waves with variable frequency, but its study is limited due to its difficulty in physical realization. This paper presents a simple yet effective $LC$-tuned WEC that generates a tunable reactive PTO force from tunable inductor $L$ and capacitor $C$ in the WEC. A complete closed loop system model of the WEC is derived first, then three quantitative rules are obtained from analyzing the model. These rules are used to tune the $LC$ network, and hence the reactive PTO force that drives the WEC, to resonate with the input wave force and generate maximal electric power over a range of wave frequencies. Mathematical analysis of the WEC and tuning rules reveals the analytical and quantitative descriptions of the WEC's mechanical power absorption, active and reactive electric power generation and power factor, optimal electric resistance load, and the generator and $LC$ capacity requirements. Simulation results show the effectiveness and advantages of the proposed WEC and verify the analysis results.