Targets and Benefits

Their Use in Key Areas of Turbine Operation

In order to achieve their design potential as credible alternative providers of energy, wind turbine systems have to employ highly efficient, reliable and robust components. Among the most important of these components are gearboxes; in particular, planetary gearboxes. One of the manufacturers of planetary gearboxes is Brevini. This article describes the company’s activities within this field.

The UK government now has ambitious targets for the overall contribution of renewable energy to the UK’s energy budget. These higher targets have resulted in an increase in applications for onshore and offshore renewable energy developments. In the UK, many of the renewable resources with the most potential are at their greatest in Scotland. This has of course created some conflict, in particular with respect to wind generation, because of Scotland’s remote habitats and the species of conservation concern, including key bird species, that use these areas. Therefore, developers and statutory bodies have been pressed to seek state of the art assessment methods for accurately gauging potential environmental impacts.

This article is about increasing confidence levels in annual energy production calculations for proposed wind farms. To do this, Sinclair Knight Merz uses detailed statistical analysis of the measured site data and the measured meteorological station data, without assuming a certain correlation function between the two datasets before the analysis has taken place.

By Paul van Lieshout, Wind Power Group Manager, Sinclair Knight Merz (Europe) Ltd, UK

New turbines above 3MW are being developed at a rapid rate in order to maximise energy yields. Therefore turbine components also have to be upgraded. A transformer is required to step up the voltage from the generator (400 to 3000V) to a medium voltage level. Safety and fire behaviour of transformers is an important issue for our industry. Fire damage accounts for between 9 and 20% of wind power insurance claims. In this article, the authors compare the safety and fire behaviour of dry-type transformers with high temperature liquid-filled transformers.

Developments in power electronics, electrical drives and wind turbines have allowed an increase in the power of wind systems. The need to limit mechanical stress and power disturbances has led to strong demand for variable speed systems. In wind generation systems it is necessary to decouple and control active and reactive power flow with fast response because of mains requirements. Fast and accurate control is especially important when the induction machine is designed to operate below synchronism rotational speed as a generator. This article describes a controller that can extract power from wind kinetic energy over a large speed range, at both sub- and hyper-synchronism speeds.

By Paulo Costa, António Martins and Adriano Carvalho, Portugal