antiplagiat antiplagiat

Abstract Wind energy market provides exciting opportunities for developers. Romanian Wind Associations forecasts that Romania may produce as much as 14000 MW on wind energy. A Wind Turbine’s reliability is the overcritical factor in the availability for Wind Power Plant WPP projects. Poor reliability directly of WTs had bad consequences on the economics of a project. Virtual monitoring instruments using HP VEE Pro Software, based on stress and acoustic noise measurements, are being developed for predicting the number of cycles that can be applied to the components before failure. This paper will provide details behind two applications: a control method of an entire tower/gearbox oscillation assembly based on inclinometer sensors and highlight the stress level for structureusing acoustic sensors. Keywords wind power plant predictive maintenance condition monitoring fatigue damage acoustic analysis software simulation. I. INTRODUCTION The major components of a typical wind energy conversion system include a Wind Turbine WT with their subsystems the tower foundation, rotor and nacelle, power grid interface and control systems. Each of mentioned subsystem has many other components. WT bear with environmental conditions such as variable speed, variable direction of wind, icing, lightning, ice, sand, rain, bird strike, variable temperature, UV rays and hurricane. All these have impact in rotational speeds and constantly changing loads. A major problem in the design, operation and maintenance of WT is the possibility to predict the lifetime of dynamically loaded structural components with a sufficient accuracy, using nondestructive techniques. A WT’s reliability is dependent largely on the quality of designed, quality of manufacture, right transport, correct installation and commissioning, operating environment that determines the loading imposed on the components and their maintenance. Larger wind turbines have a lower reliability than smaller ones. New designs and revolutionary materials are being incorporated in current WT. Technology is developing for decrease weight, controlling loads, and rising wind energy capture with the final aim of reduction the cost of energy. Key to reducing operation and maintenance costs is to predict failures before they lead to a catastrophic failure and reduce unexpected downtime costs. Gearbox, generators and wind blades represent almost 90% of all maintenance and operational costs. The benefits from measuring standard signals are manly used for WT control and for monitoring purposes. Condition monitoring and diagnose regarding stress and acoustic analysis is a important issue, because a considerable number of failures due to fatigue cracks in the load bearing structures have occurred, both on large and small WTs. Using HP VEE Pro Software, we developed applications of spectral analysis for investigation of fatigue damage and acoustic emission. The analysis demonstrates that fatigue calculation results should be seen as point results from a multidimensional distribution of all possible events. For instance, loading level, residual stress level, material quality, surface treatment and surface finish are just few of the inputs that could exhibit statistical variation. The influence of these possible variations is an important aspect of achieving a robust design. This paper will show how two of these variables, meaning the stress and noise level, can have a significant effect on achieved life of the WPP.