Transformers: Maintenance, and Diagnostics

Transformers: Maintenance, and Diagnostics

Transformers have been used at powerplants since the inception of alternating-current generation, a century ago. While operating principles of transformers remain the same, the challenges of maintaining and testing transformers have evolved along with transformer design and construction. Modern transformers are designed to closer tolerances than transformers in the past. Thus,effective, regular maintenance and testing is even more essential to continued operation when traditional “overdesign” cannot be relied on to overcome abnormal conditions. The utility engineer must be familiar with all aspects of maintenance and testing and make use of state-of-the-art tools and techniques for evaluating transformer condition. While on-line diagnostic systems and computerized testing methods are very helpful, they are not a substitute for sound engineering judgment and expertise. 


1. Introduction

2. Introduction to Transformers
3. Routine Maintenance 

4. Oil-Filled Transformer Inspections
5. Gaskets
6. Transformer Oils

7. Transformer Oil Tests that Should Be Completed
8. Silicone Oil-Filled Transformers
9. Transformer Testing

U.S. Department of the Interior
Bureau of Reclamation
Technical Service Center
Infrastructure Services Division
Hydroelectric Research and Technical Services Group
Denver, Colorado