National Institute of Technology, Karnataka

About: National Institute of Technology, Karnataka is a education organization based out in Mangalore, Karnataka, India. It is known for research contribution in the topics: Computer science & Corrosion. The organization has 5017 authors who have published 7057 publications receiving 70367 citations.

Electrical Fault Detection in Three Phase Squirrel Cage Induction Motor by Vibration Analysis using MEMS Accelerometer

Abstract: The ever increasing applications of 3phase Induction motor have resulted in a growing awareness on addressing various performance demands. The condition monitoring of these electrical machines has received considerable attention in recent years. The diagnostics based on vibrations produced by these motors can form valuable data for preventive maintenance of these machines. The vibration analysis demands appropriate vibration transducer. With the advent of MEMS [Micro Electro Mechanical Systems], Technology I.C. chip mounted accelerometers are available. These accelerometers are having merits of low cost, high reliability, and low power consumption when compared to piezoelectric types which are conventionally used earlier. These accelerometers are gaining wide acceptance in condition monitoring of electrical machines. This paper presents the instrumentation developed around MEMS accelerometer and also proposes a technique of detecting abnormal electrical operating conditions in 3phase Induction motor such as single phasing, voltage unbalance by employing spectrum analysis of vibrations measured through MEMS accelerometer.

Erratum to: Effect of annealing on the properties of zinc oxide nanofiber thin films grown by spray pyrolysis technique

Abstract: Zinc oxide nanofiber thin films have been deposited on glass substrate by spray pyrolysis technique. The X-ray diffraction studies revealed that the films are polycrystalline with the hexagonal structure and a preferred orientation along (002) direction for films annealed for 1 h at 450 °C. Further increase in annealing time changes the preferred orientation to (100) direction. The scanning electron microscopic analysis showed the formation of ZnO nanofiber with an average diameter of approximately 800 nm for annealed films. The compositional analysis of nanofiber ZnO thin films were studied by time of flight secondary ion mass spectroscopy, which indicated oxygen deficiency in the films. The optical properties of annealed films have shown a variation in the band gap between 3.29 and 3.20 eV. The electrical conductivity of the as grown and annealed films showed an increase in the conductivity by two orders of magnitude with increase in annealing duration.