ABSTRACT
Bearing fault is the most frequent malfunction in all kinds of motor faults. At present, motor current signature analysis is one of the popular research objects. Considering that the weak characteristic frequency in the spectrum analysis of the stator current is blanketed by the fundamental component and the hard-to-highlight fault characteristic, a method based on harmonic injection for induction motor bearing faults diagnosis is proposed. In this paper, the expression of stator current in the injection frequency band while bearing faults is given and analyzes the factors that affect the current characteristic frequency identification process. A motor drive system based on FPGA, which can inject a particular harmonic signal, is designed. This system can provide the related experimental environment. The experimental results show that the proposed method is effective in bearing fault detection and recognition.
