Listening for early signs of equipment failure: Alliant Energy applies ultrasonic/partial-discharge testing for predictive-maintenance practices

摘要

Industry competitive pressures have forced utilities to optimize operation and reduce maintenance costs, in other words, do more with fewer resources. In 1993, utilities made a major effort to re-evaluate preventive-maintenance activities based on extensive personnel experience, and electrical and diagnostic testing methods available at that time. Most utilities use a time-based preventive approach to substation maintenance. This approach dictates maintenance scheduling strictly related to time in service rather than equipment condition. Frequently, funds are misdirected for maintenance performed on equipment that does not require maintenance. This misdirection of funds created the need for an online condition assessment of power transformers and associated substation equipment. The EPRI M&D Center, working in cooperation with predictive-maintenance (PDM)-member utilities, implemented a PDM program that incorporated the following technologies: · Vibration Analysis · Ultrasonic Noise Analysis · Partial-Discharge Detection (PDD) · Portable Gas in Oil Analysis · Infrared Thermography · Sound Level Testing · Ultrasonic Bearing Wear Detection.