High Temperature Magnetic Sensors for the Hot Section of Aeroengines

An Accelerometer Based on All Silica In-Line Fiber Fabry-Perot Etalon for High Temperature up to 800 °C

High-temperature accelerometers have been widely used in aerospace, nuclear reactors, automobile technologies, etc. In this paper, a fiber-optic Fabry–Perot accelerometer (FOFPA) with a cantilever beam for high temperature is designed and experimentally demonstrated. The FOFPA is formed by bonding an all-silica in-line fiber Fabry–Perot etalon (ILFFPE) to one surface of the uniform cantilever beam with the lumped mass at the free end for acceleration measurement. The all silica in-line fiber FP etalon is made by welding two gold-coat single-mode fiber (GSMF) and a hollow silica glass tube (HST). The research results indicate that the sensitivity of the FOFPA is 0.02328rad/g, and the resonance frequency is 1146.6 Hz in the range of 1 g ~ 10 g. The high-temperature performance of the FOFPA was also evaluated. From 20 °C to 800 °C, the temperature drift is about 0.3178 nm/°C. The FOFPA has the potential of being applicable in higher temperatures compared to conventional accelerometers.

Methods of Condition Monitoring and Fault Detection for Electrical Machines

Nowadays, electrical machines and drive systems are playing an essential role in different applications. Eventually, various failures occur in long-term continuous operation. Due to the increased influence of such devices on industry, industrial branches, as well as ordinary human life, condition monitoring and timely fault diagnostics have gained a reasonable importance. In this review article, there are studied different diagnostic techniques that can be used for algorithms’ training and realization of predictive maintenance. Benefits and drawbacks of intelligent diagnostic techniques are highlighted. The most widespread faults of electrical machines are discussed as well as techniques for parameters’ monitoring are introduced.