ANALYSIS AND FEATURE EXTRACTION OF VIBRATIONAL SIGNAL FROM ELECTRICAL MACHINES

Abstract

The nature of the vibration signals from the rotating electrical machines depends upon their mechanical assembly, rotational speed, base alignment, states of the bearings, and electrical conditions. The vibrations affect the mechanical life span and electrical performance characteristics, and may bring about a situation resulting In the failure of overall machine system. It is essential to carry out the detailed analysis of the recorded vibration signal for taking the necessary precautions for avoiding the mechanical and electrical problems due to vibrations in electrical machines. The present work deals with the development of software for the analysis of the vibration signals recorded from an electrical machine. By using the developed software, the detailed analysis and feature extraction from the vibration signal In respect of amplitude, duration, velocity, acceleration, and periodicity have been carried out in this work.As the vibration transducer of high frequency response was not available to record the signal from electrical machines, the developed software has been tested using vibration signal from the vibration table.The transducer used was a piezoresistive based seismic accelerometer having a frequency range upto 100 Hz. The vibration signal was picked up using this accelerometer and processed and digitized by an ADC card fitted within the computer system. The digitized signal was stored and analyzed by using the developed software. The test results are consistent and reliable and establishes the authenticity of the method to be used for real time vibration signal analysis of rotating electrical machines. iii