Certain investigation on motor stator current profile for fault identification in medium voltage induction motors

Abstract

Induction Motors are the prime moving force in any industrial automation. Its unmatched performance, less cost, rugged construction, minimum maintenance, and ease of speed control are some of the major key features makes it to occupy any position in electro-mechanical energy conversion. The population of these motors in industrial environment speaks its advantages. Equipment fitted with induction motors need less attention compared to other type of motors. Although these motors have a number of advantages, there is always a possibility of failure occurring in these motors. Failure may be due to internal problems or due to external problems. Since these motors are fitted in critical operations, failure in these motors ends in total shut down. The healthiness of these motors should be regularly ensured to avoid unnecessary downtime. Motor Stator Current acts as a transducer which always reflects the real condition of the motor. Any fault arising in these motors will certainly have an impact in stator current signature. This research work proposes Rigorous Analysis of Current Envelope (RACE) to provide a best way in pre-determining the healthiness of the medium voltage induction motor under the influence of Stator faults such as Unbalance Voltage, Winding Inter-turn fault, Rotor faults such as broken rotor bar, Mechanical faults such as air-gap eccentricity and bearing fault, etc. Stator current is captured and investigated to understand the condition of motor. Many researchers have carried out different techniques to identify the nature of fault based on stator current. newline newline newline