Vestas

About: Vestas is a company organization based out in Aarhus, Denmark. It is known for research contribution in the topics: Turbine & Wind power. The organization has 1075 authors who have published 1519 publications receiving 23285 citations. The organization is also known as: Vestas Wind Systems & Vestas Wind Systems A/S.

Method and system for monitoring bending strains of wind turbine blades

Abstract: The invention provides a method and system of monitoring bending strain on a wind turbine blade. The method in one aspect comprises: locating at least three strain sensors on the turbine blade, in use each strain sensor providing a strain measurement, the strain sensors located such that edgewise and flapwise bending can be determined from the strain measurements; calculating a plurality of resultant bending strains using the strain measurements; calculating an average resultant bending strain from the plurality of resultant bending strains; and calculating a confidence value for a first sensor based on a comparison of resultant bending strains derived from the strain measurement from the first sensor with the average resultant bending strain.

A sealing device for a tubing arrangement

Abstract: A sealing device (1) for a tubing arrangement (2), preferably for use in an offshore facility, such as an offshore wind turbine or an oil rig The tubing arrangement (2) has a cable (3) or an inner tube arranged in an interior part thereof The sealing device (1) comprises a substantially rigid housing (4) and a flexible plug part (5) arranged in an interior part of the housing (4) The housing (4) is mountable on or forms part of the tubing arrangement (2) in such a manner that the interior part of the housing (4) communicates with the interior part of the tubing arrangement (2) The flexible plug part (5) comprises an inlet opening connectable to a grout source When grout material (7) is supplied to the flexible plug part (5), the flexible plug part (5) expands, thereby providing sealing between the housing (4) and a cable (3) or inner tube arranged in the interior of the tubing arrangement (2) The sealing device (1) can be mounted on the tubing arrangement (2) before the tubing arrangement (2) is mounted on an offshore facility, and the grout material (7) can be supplied at a later time Use of divers is thereby minimised The sealing device (1) can easily be removed and replaced

Design and Implementation of a 12-Pulse TCR-Based SVC for Voltage Regulation

Abstract: Thyristor Controlled Reactor (TCR) based static VAr compensator (SVC) systems can be implemented with several optional topologies which depends on the required functions and associated costs. In this paper, the analysis and implementation of a 12-pulse TCR-based voltage regulation type SVC system is discussed. In literature, this paper represents the most detailed field implementation and discussion of a 12-pulse TCR-based SVC system that is used for voltage regulation purposes. Principles of operation and overall design assessment are described. This system has been installed to mitigate the voltage regulation problem in a village located in Durma area, Saudi Arabia. The entire installation consists of two identical (except for power transformers) SVCs with a rated power of 1.5 MVAr each. A cascaded PI control algorithm is implemented and steady and dynamic states are assessed. Test results from the field are given with a discussion of the overall performance.

Ramping power in a wind turbine using gain scheduling

Abstract: The invention relates to a control system for a wind turbine. The wind turbine comprises a power generator configured to generate power dependent on a power reference and a pitch system configured to adjust the pitch of a blade of the wind turbine dependent on a pitch request. The control system comprises a controller configured to determine the pitch request dependent on an adjustable gain. A gain scheduler comprised by the control system is configured to set the adjustable gain to an increased gain value if a rate of change of the power reference, e.g. an external power reference, exceeds a threshold.

Power ramp rate limiter for wind turbines

Abstract: The invention relates to a method for limiting structural loads in a wind turbine in situations where the power produced by the wind turbine is increased or decreased. The limitation of structural loads is achieved by restricting the power ramp rate, i.e. the rate of change of increases or decreases in produced power. The restriction is only invoked if a maximum change of the produced power or the corresponding internal power reference within a time window exceeds a given threshold.