Fuzzy Supervision Based-Pitch Angle Control of a Tidal Stream Generator for a Disturbed Tidal Input

Tidal Supplementary Control Schemes-Based Load Frequency Regulation of a Fully Sustainable Marine Microgrid

The world is targeting fully renewable power generation by the middle of the century. Distributed generation is the way to increase the penetration level of renewable energies. This paper presents load frequency control of a hybrid tidal, wind, and wave microgrid to feed an isolated island. This research is a step towards 100% renewable energy communities in remote seas/oceans islands. The wave and tidal generation systems model are presented. The study presents load frequency control through three supplementary control strategies: conventional integrators, fractional order integrator, and non-linear fractional order integrator. All the controllers of the microgrid are designed by using a novel black widow optimization technique. The applied technique is compared to other existing state-of-the-art algorithms. The results show that the black widow non-linear fractional integrator has a better performance over other strategies. Coordination between the unloaded tidal system and blade pitch control of both wind and tidal systems are adopted in the microgrid to utilize the available reserve power for the frequency support. Simulation and optimization studies are performed using the MATLAB/SIMULINK 2017a software application.

Energy Yield Assessment from Ocean Currents in the Insular Shelf of Cozumel Island

Marine renewables represent a promising and innovative alternative source for satisfying the energy demands of growing populations while reducing the consumption of fossil fuels. Most technological advancements and energy yield assessments have focused on promoting the use of kinetic energy from tidal streams with flow velocities higher than 2.0 m s−1. However, slower-moving flows from ocean currents are recently explored due to their nearly continuous and unidirectional seasonal flows. In this study, the potential of the Yucatan Current was analysed at nearshore sites over the insular shelf of Cozumel Island in the Mexican Caribbean. Field measurements were undertaken using a vessel-mounted Acoustic Doppler Current Profiler (ADCP) to analyse the spatial distribution of flow velocities, along with Conductivity-temperature-depth (CTD) profiles as well as data gathering of bathymetry and water elevations. Northward directed flow velocities were identified, with increasing velocities just before the end of the strait of the Cozumel Channel, where average velocities in the region of 0.88–1.04 m s−1 were recorded. An estimation of power delivery using horizontal axis turbines was undertaken with Blade Element Momentum theory. It was estimated that nearly 3.2 MW could be supplied to Cozumel Island, amounting to about 10% of its electricity consumption.

Special Issue “Offshore Renewable Energy: Ocean Waves, Tides and Offshore Wind”

Offshore renewable energy includes several forms of energy extraction from oceans and seas, and the most common and successful offshore technologies developed so far are based on wind, wave and tides. [...]