UKERC EDC: ETI

Citation	Smailes, M., Ng, C., Mckeever, P., Shek, J., Theotokatos, G. and Abusara, M. Hybrid, Multi-Megawatt HVDC Transformer Topology Comparison for Future Offshore Wind Farms, Energies, 10(7): 851, 2017. https://dx.doi.org/10.3390/en10070851. Cite this using DataCite
Author(s)	Smailes, M., Ng, C., Mckeever, P., Shek, J., Theotokatos, G. and Abusara, M.
Project partner(s)	Offshore Renewable Energy Catapult (ORE Catapult), University of Edinburgh, Strathclyde University, Exeter University
Publisher	Energies, 10(7): 851
DOI	https://dx.doi.org/10.3390/en10070851
Abstract	With the wind industry moving further offshore, High Voltage Direct Current (HVDC) transmission is becoming increasingly popular. HVDC transformer substations are not optimized for the offshore industry though, increasing costs and reducing redundancy. A suggested medium frequency, modular hybrid HVDC transformer located within each wind turbine nacelle could mitigate these problems, but the overall design must be considered carefully to minimize losses. This paper’s contribution is a detailed analysis of the hybrid transformer, using practical design considerations including component library minimization. The configurations investigated include combinations of single phase H-Bridge and Modular Multilevel Converter topologies operating under minimum switching frequency control strategies. These were modelled in the MATLAB/Simulink environment. The impact of the minimum switchingcontrol strategy and converter topology on power transfer stability and overall efficiency is then investigated. It was found that the H-Bridge converter generated the lowest overall losses, but there was a trade off with power flow sensitivity due in part to the additional harmonics generated.
Associated Project(s)	ETI-MA2003: Industrial Doctorate Centre for Offshore Renewable Energy (IDCORE)
Associated Dataset(s)	No associated datasets
Associated Publication(s)	A model to map levelised cost of energy for wave energy projects An Integrated Data Management Approach for Offshore Wind Turbine Failure Root Cause Analysis An investigation of the effects of wind-induced inclination on floating wind turbine dynamics: heave plate excursion Application of an offshore wind farm layout optimization methodology at Middelgrunden wind farm Characterisation of current and turbulence in the FloWave Ocean Energy Research Facility Characterization of the tidal resource in Rathlin Sound Comparison of Offshore Wind Farm Layout Optimization Using a Genetic Algorithm and a Particle Swarm Optimizer Component reliability test approaches for marine renewable energy Constraints Implementation in the Application of Reinforcement Learning to the Reactive Control of a Point Absorber Control of a Realistic Wave Energy Converter Model Using Least-Squares Policy Iteration Cost Reduction to Encourage Commercialisation of Marine in the UK Cumulative impact assessment of tidal stream energy extraction in the Irish Sea Design diagrams for wavelength discrepancy in tank testing with inconsistently scaled intermediate water depth Development of a Condition Monitoring System for an Articulated Wave Energy Converter Dynamic mooring simulation with Code(-)Aster with application to a floating wind turbine ETI Insights Report - Wave Energy Environmental interactions of tidal lagoons: A comparison of industry perspectives Exploring Marine Energy Potential in the UK Using a Whole Systems Modelling Approach Hydrodynamic analysis of a ducted, open centre tidal stream turbine using blade element momentum theory Offshore wind farm electrical cable layout optimization Offshore wind installation vessels - A comparative assessment for UK offshore rounds 1 and 2 Optimisation of Offshore Wind Farms Using a Genetic Algorithm Quantifying uncertainty in acoustic measurements of tidal flows using a “Virtual” Doppler Current Profiler Re-creation of site-specific multi-directional waves with non-collinear current Reactive control of a two-body point absorber using reinforcement learning Reactive control of a wave energy converter using artificial neural networks Reliability and O & M sensitivity analysis as a consequence of site specific characteristics for wave energy converters Reliability prediction for offshore renewable energy: Data driven insights Resource characterization of sites in the vicinity of an island near a landmass Review and application of Rainflow residue processing techniques for accurate fatigue damage estimation Sensitivity analysis of offshore wind farm operation and maintenance cost and availability Simulating Extreme Directional Wave Conditions Testing Marine Renewable Energy Devices in an Advanced Multi-Directional Combined Wave-Current Environment Testing the robustness of optimal access vessel fleet selection for operation and maintenance of offshore wind farms The Industrial Doctorate Centre for Offshore Renewable Energy(IDCORE) - Case Studies The SPAIR method: Isolating incident and reflected directional wave spectra in multidirectional wave basins The effects of wind-induced inclination on the dynamics ofsemi-submersible floating wind turbines in the time domain The power-capture of a nearshore, modular, flap-type wave energy converter in regular waves UK offshore wind cost optimisation: top head mass (Presentation to All Energy, 10th May 2017)

Hybrid, Multi-Megawatt HVDC Transformer Topology Comparison for Future Offshore Wind Farms