Simulação de esforços mecânicos provocados pelo efeito esteira em parques eólicos: estudo de caso

Abstract

The wind turbines (WTG) installed in wind farms are selected for twenty years of operation. The projects consider that wind turbines consider the loads specified in international standards (International Standard IEC 61400-1) based on average wind speed and assumed turbulence.Such standards are conservative and, as a rule, the loads defined in the design phase are not achieved when the life of the wind turbine has elapsed. Comparison methods between the design loads and the loads actually applied make it possible to predict the survival time of the wind turbines and the cost reduction of this evaluation. This work evaluated a proposed method for calculating component damage on project loads and comparing with actual loads verified in a wind farm (in situ). These damages are caused by the interference of one wind turbine on the other, causing greater turbulence. This interference is called the wake effect. With the aid of the commercial program wp.neo-wake for monitoring wind farms, they were calculated as applied load depending on the distribution of direction and wind intensity for each wind turbine and damage estimates. With regard to the calculation of damages in steel components, the common method of equivalent loads of damage 1Hz (DEL) will be applied over a comparison of different load spectra. The additional time (survival) of operation is finally greater from the comparison of the damage predicted in the project for wind turbines after twenty years of service with the damages calculated according to the established in IEC norm, from the data of the distribution, direction and intensity in a real wind farm located in Rio Grande do Norte in the city of Guamaré and with 31 turbines. The wp.neo-wake program was optimized for the generation of load in the wind farm considered, showing that independent wind turbines suffer less damage (as expected) and have a longer life than wind turbines with partial or total. Combining the wp.neo-wake program and the method developed, a trend can be determined. This trend can provide information about which wind turbines are particularly affected by the layout of the turbines in the park and which components of the system suffer the most damage. The computer program used throughout this work was designed and developed in modules and allows the integration of new models of wind turbines.