Multiple frequency fault detection, correction and identification of vibration forces on the rotor of a rotational active magnetic bearing system

Abstract

In this paper, the authors propose a real-time multiple frequency fault detection, correction and identification system for vibration forces on the rotor of a rotational active magnetic bearing (AMB) system. Condition monitoring was performed on the displacement signals of a fully suspended 250 kW water cooling AMB pump, to obtain historical fault data. A pattern recognition system compared the realtime displacement error patterns with the displacement error patterns from the historical fault database. A fuzzy logic system used the patterns from the pattern recognition system to perform error correction. The Wigner-Ville distribution extracted the vibratory amplitudes and frequencies, which was used as input features to the pattern construction and pattern recognition systems. Experiments were performed on a double radial AMB test rack to demonstrate the effectiveness of the proposed system in the detection, correction and identification of vibration forces on the rotor of an AMB system. The detection and correction system was able to correct and minimize multiple frequency vibration forces to a stable working condition. The identification system calculated the type, parameters, vibratory level and zone of the vibration forces. The main advantage of this system is its capability to detect, correct and identify multiple frequency vibration forces.