New approaches on fault detection and diagnosis for structures maintenance management

Resumen

The renewable energy industry is in a constant improvement in order to cover the current demands. Within the renewables energies, wind energy and concentrated solar power (CSP) are two of the fastest growing sources of renewable energy production. Wind farms, in contrast to the conventional power plants, are exposed to the inclement and variability of weather. As a result of this variations, wind turbines are subjected to high mechanical loads, which require a high degree of maintenance to provide accost-effective power output and care the life cycle of the equipment [1-3]. Nowadays, the demand for wind energy continues raising at an exponential rate, due to the reduction in operating and maintenance costs and increasing reliability of wind turbines [4,5]. CSP is an alternative to onshore wind farms and photovoltaic which has received significant attention in recent years. Particularly, in southern countries, where the sunlight is and abundant resource. It is crucial to ensure that the solar receivers work properly to avoid failures, and to increase the reliability, availability, safety and maintainability. Both renewable energies have some monitoring systems that allow to know the status of critical components, and to determine anomalous operating situations. The power generation plants have incorporated a basic online monitoring control system. This system generally includes sensors for monitoring the machine parameters, such as temperature, speed, fluid levels, unbalance in the rotor, etc. [6] The Condition Based Maintenance (CBM) is and advanced maintenance strategy based on monitoring data on the machine status. It can obtain measurements of condition monitoring of wind turbine or CSP components [7-10]. The main objective of CBM is to optimize maintenance activities and to reduce costs. Non-Destructive Testing (NDT) is used in Structural Health Monitoring (SHM) systems for Fault Detection and Diagnosis (FDD). Within the CBM, some NDT techniques are used to prevent serious failures in critical components such as blades, gearbox, tower or receiver tubes. [11,12]. The techniques for condition monitoring employed in this work are based on the infrared radiometry and the ultrasonic guided waves. Infrared remote sensing techniques are based on the reception and analysis of the electromagnetic energy reflected or emitted by a surface. The Guided Waves are non-destructive techniques widely used for structural evaluation of plates or pipes. The aim of this work is to develop new approaches for condition monitoring of wind turbines and concentrated solar plants based on infrared technology and guided waves.