3-Phase Induction Motor Faults'severity Detection Using Fuzzy Logic And On-Line Condition Monitoring Of Faults Using Labview-Gui

Abstract

Induction motors are critical components in many industrial processes. Induction machines play a pivotal role in industry and there is a strong demand for their re- liable and safe operation. They are generally reliable but eventually do wear out. Faults and failures of induction machines can lead to excessive down-times and gen- erate large losses in terms of maintenance and lost revenues, and this motivates the examination of fault condition monitoring. Therefore intelligent protection system design of induction motors is becoming increasingly important. The main di culty in this task is the lack of an accurate analytical model to describe a faulty motor having di erent types of faults. Since in the classical protection systems, the protective operating time is adjusted constantly without noticing fault severity. So if temporary faults are detected in the system, stopping motor immediately without waiting will lead disruption of the pro- duction line and similarly, if system waits too long to stop motor in a critical fault level and it will lead serious damage to motor. So overcome this problematic situa- tion, fault severity has to be detected. In this thesis, a fuzzy logic based fault severity detection strategy is employed to detect fault severity and so that according to fault severity, a control strategy can be employed.Since a micro-controller only accepts DC voltage signal, a full wave uncon- trolled recti er is designed to convert measured three line AC voltages into DC form. And it is fabricated and tested on DSO (Digital Storage Oscilloscope) for design ver- i cation. An overview of a severity of bearing wear fault and under-voltage fault detection us- ing fuzzy logic is represented.. A fault severity detection scheme against an over voltage and a supply voltage un- balance using fuzzy logic is represented. Also a fuzzy logic based protection strategy against an over voltage and a supply voltage unbalance is demonstrated in the MAT- LAB 6.5- Fuzzy Logic Toolbox. An algorithm for protection against over voltage and supply voltage unbalance is pro- posed, coded by using C language in mikroC compiler(v5.3)and veri ed in Real PIC Simulator. An on-line fault severity monitoring is done in LabVIEW-GUI using a serial commu- nication. For it, a RS232 driver circuit using MAX232 IC is used.