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- Category: Articles
How a New Class of Wind Turbine was Developed
What do you do when you want a wind turbine, but it is not possible because of local planning regulations? Most people would just give up and look elsewhere for their renewable energy, but not Win Keech. Win lives in the North York Moors National Park, a beautiful part of northern England, with extremely rigorous planning requirements, so much so that in the 1,500 km2 park (which is in one of the windiest parts of the UK) there is only one wind turbine installed. To Win, the solution was obvious, he decided to invent his own wind turbine that would be acceptable to the planners.
By Dean Gregory, Co-founder, The Power Collective Ltd, UK
- Category: Articles
A Study of Torsional Reversals Caused Through Wind Events and Operating Conditions
Although wind turbines have been around for decades, recent research has been focused on what occurs with a wind turbine under various wind conditions. It is understood anecdotally that high gusts and turbulent winds can add to the chance of breakdown of wind turbine equipment and lead to an increase in O&M and capital costs. Ridgeline and downwind turbines see higher O&M costs. Most of the earlier focus was on the effects on blades and tower structures. New data shows how the entire drive-train sees an impact from these transient events. Drive-train torque monitoring on various turbine models has shown that an asymmetrical torque control device reduces the damaging loads and helps extend turbine life.
By Doug Herr, General Manager, AeroTorque Corp., USA
- Category: Articles
Root Cause Hypotheses and How to Prevent Failures
The failure of bearings due to the development of white-etching cracks (WEC) in the inner ring of the bearing has become a leading cause of wind turbine gearbox unreliability. The failures are not confined to any single gearbox or bearing manufacturer, but are systemic throughout the industry. The root cause of the failures is not known, although many theories have been proposed and are currently under investigation. Even though the cause of failures is not well understood, risk factors that make a bearing more prone to experience WEC failures are known, as are factors that make a bearing less prone to these failures. By following some simple best practice guidelines in the selection of bearings, WEC bearing failures can be minimised or prevented altogether.
By Rob Budny, President, RBB Engineering, USA
- Category: Articles
The Growing Role of Technical Certification in Distributed Wind
The European distributed wind market, where power is produced using small or medium-scale turbines close to where it is consumed, is still at an early stage of development. While medium-scale manufacturers and developers in the UK and Italy have profited from incentives that have spurred growth, other countries are yet to match this level of activity. And, even in the relatively established markets, uncertainty over tariff levels and variations in the certification requirements for different sizes of turbine have not helped things.
By Miguel Hoyos Irisarri, Technical Director, Norvento, Spain
- Category: Articles
Modern, Wind-specific Technology Provides Optimised Performance, Remote Monitoring and Control
Rapid developments in electronics and control systems over the last 30 years have provided new opportunities for operation of wind turbines. Retrofitting older turbines with a modern control system provides the turbine owner with significant improvements in relation to remote monitoring, control and root cause analysis. Although retrofitting a control system is a technical challenge, the benefits are clear: improved turbine performance both in terms of availability and power production. This article describes the challenges and results of a customer project undertaken by KK Wind Solutions to develop and install retrofit solutions for a Bonus 1.3MW and a Vestas V47 turbine.
By René Balle, Chief Technology Officer, KK Wind Solutions, Denmark
- Category: Articles
AdBm Butendiek Noise Reduction Demonstration
AdBm Technologies, working with WPD and Ballast Nedam, demonstrated their new underwater noise abatement system during pile-driving operations in the construction of the Butendiek Offshore Wind Farm in the North Sea. The panel-based AdBm system was smoothly and quickly deployed and recovered four times. Acoustic testing was conducted at three locations ranging from 285 to 750 metres from where the monopile was being driven. Measurements were collected on 668 hammer strikes at a distance of 285 metres from the monopile. Attenuation of up to 36.8dB was realised across all hammer strikes at this location. At 750 metres from the monopile, 136 hammer strikes were analysed and the noise radiated from the pile-driving was attenuated to the level of ambient noise near the recording vessel, which ranged on average from 140 to 150dB at a reference pressure of 1 µPa. These results demonstrate that frequency-targeted reduction of underwater noise is possible and can be highly effective.
By Mark Wochner, CEO, AdBm Technologies, USA
- Category: Articles
Investigating the Feasibility of Self-Buoyant Concepts
The gravity concept, originally implemented in the Oil & Gas sector, is based on utilising the dead weight of the foundation material (typically concrete) to generate the restoring forces required to resist the high lateral loads and overturning moments resulting from the service loads. However, the significant dead weight of the foundation usually results in costly transportation and installation operations, given the high charter rates of the required vessels, lifting cranes and infrastructures. Achieving the EU targets for the levelised cost of energy (LCOE) of offshore wind encourages development of alternative approaches with cost reduction potentials. Several gravity concepts have been proposed in recent years, to attain a self-buoyant gravity base foundation, and thereby minimise the need for costly marine operations. This article reports a parametric study that investigates the feasibility and cost-benefit of such concepts, in terms of performance, intermediate stability and their impact on the overall cost of foundations.
By Dr Azadeh Attari and Dr Paul Doherty, GDG, Ireland
