Research On The Fault Diagnosis Methods For The SATI And Intelligent Equipment

Three-phase Induction Motor with Squirrel-cage Aluminum-rotor is widely used because of its excellent performance and low price. The performance of the aluminum-rotor affect the quality of the motor. In order to control the quality of the motor and test the aluminum-rotor automatically, we write this thesis: Research on the Fault Diagnosis Methods for the SATI (short for Squirrel-cage Aluminum-rotor of Three-phase Induction Motor) and Intelligent Equipment.With the views of basic electromagnetic and electrical machine theory, this thesis gives interpretation, fault-character and its causation of the faults on SATI.The common inductance computational formulae are suited to the normal condition. These formulae cannot be used to fault condition. According to the winding function and the expression of air gap, this thesis gives out computational formulae for the stator and rotor inductance parameters in the induction motor under both normal and fault conditions. Simulation results tally with that of experiments, which indicates correctness of the models and the parameters computation.The previous methods to analysis the spectrum of line current always cannot highlight the characters of the broken bar since the frequency of the fault component is very close to the power frequency. Therefore this research proposes three different fault diagnose method:(i) The method based on Hilbert mode spectrum analysis (ii) The method based on vector control (iii) The method based on spectrum analysis of instantaneous power. We choose The method based on spectrum analysis of instantaneous power in the research.Harmless-diagnosis based on ultrasonic can show the fault of the the SATI visualized. We can notice all the fault of SATI such as crack,air bubble and others.With all the fault-analysis above, we schemed the diagnosis methods and equipment of SATI, mainly include the structure of the equipment, the sensor parts and so on.This thesis which include the knowledge of electrics,magnetics,acoustics, mathematics, mechanism is hard to solve. We are not have enough time and money to finished the sample of diagnosis equipment,and we hope that the comer can finish it.