Detection of Broken Rotor Bar Fault of Three Phase Induction Motor by Fast Fourier Transform Using ARM Microcontroller

Induction machines are the backbones of many industrial processes due to its robustness and reliability. Condition monitoring of induction motors is the process of monitoring the behavior of motor before significant change which leads to developing fault. Online fault diagnostics of induction motor is important, and its real function is to attempt to recognize the development of faults at an early stage, which are highly useful preventive rescue especially in high power applications. Researches reveal that motor currents and/or voltages signals are always modulated by fault condition inside the motor. Using different signal processing and mathematics techniques, these signals can be analyzed, interpreted and faults inside the motor can be identified. It is observed that the fault frequencies for different faults of induction motor are unique. MCSA (Motor Current Signature Analysis) technique using FFT (Fast Fourier Transform) approach is utilized in this research work to identify broken rotor bar fault of induction motor under different loading conditions. Hence in this paper RISC (Reduced Instruction Set Computing) based ARM (Advanced RISC Machine) architecture controller (LPC2148 from NXP) for current signature analysis is developed to analyze the broken rotor bar fault. An experimental setup, using the ARM based data acquisition board and PC based analysis software is also developed and results are given for multiple broken rotor bars fault.