Committee Report: IEEE Transformers

Scott Reed Specifications & Standards, Spring 2021 Specifications & Standards

The IEEE Transformer Committee was forced to cancel the 2020 spring meeting due to the global pandemic but was able to conduct the fall meeting virtually. Within the Insulating Fluids Subcommittee, a new task force was formed for C57.104, IEEE Guide for The Interpretation of Gases Generated in Oil-Immersed Transformers (DGA). The task force will study how to improve the correlation between DGA status and the actual issues within the transformer as well as how to form a common database for all DGA data.

The working group for IEEE C57.166, Guide for Acceptance and Maintenance of Insulating Liquids in Transformers and Related Equipment expects to have a draft guide this year that will consolidate fluid-quality thresholds for all fluid types into one guide. Using this same philosophy, the subcommittee also formed a task force to evaluate revising IEEE C57.637, Guide for the Reclamation of Insulating Oil and Criteria for Its Use to include the maintenance of other fluids such as natural esters.

Because of the number of silicone-filled transformers that remain primarily in the industrial market, a working group was formed to evaluate C57.146, IEEE Guide for Interpretation of Gasses Generated in Silicone-Immersed Transformers. The working group is taking a similar approach as to how C57.104 analyzed DGA data and plans to potentially develop DGA statuses.

Within the Power Transformer Subcommittee, C57.93, IEEE Guide for The Installation and Maintenance of Liquid-Immersed Power Transformers formed a task force in China that is specifically evaluating a cold-start procedure for transformers filled with natural esters. A concern with natural esters is the high pour point, which can cause the fluid to solidify at low temperatures. The task force hopes to adopt a procedure for safely energizing a transformer that can be incorporated into the guide.

In other areas of the Power Transformer Subcommittee:

  • C57.170, Condition Assessment of Transformers. A working group was formed. The goal is to develop a guide that analyzes how to assess the critical components of a transformer.
  • C57.162, Moisture in Insulation. The working group developing a guide has requested an extension to complete the project. Moisture in paper is a complex and important subject matter.
  • C57.150, Guide for the Transportation of Transformers and Reactors Rated 10,000 kVA or Higher. The working group is currently evaluating comments from the circulated draft document and will be resolving the comments so the guide can be completed.
  • C57.143, IEEE Guide for Application for Monitoring Equipment to Liquid-Immersed Transformers and Components. Work continues on updating the guide.
  • C57.148, IEEE Guide for Control Cabinets for Power Transformers. The work was completed and should be published later this year.

Within the Performance Characteristics Subcommittee, work continues on the guide for C57.149, IEEE Guide for the Application and Interpretation of Frequency Response Analysis for Oil-Immersed Transformers, also known as SFRA. One area of focus is the effects of grounding and how it influences the test results.

Within the Standards Subcommittee, a PAR was approved so that a working group could be formed to revise C57.152, IEEE Guide for Diagnostic Field Testing of Fluid-Filled Power Transformers, Regulators, and Reactors. The working group has taken an approach to create three main sections for the testing of oil-filled transformers: the main tank, bushings, and tap changers. 

Within the Bushing Subcommittee, work continues on C57.19.00, IEEE Standard General Requirements and Test Procedure for Power Apparatus Bushings. The group expects it will take one more meeting to finish the draft guide so it can go out for ballot. 

Within the Dielectric Tests Subcommittee, work continues on resolving the draft comments for C57.160, IEEE Guide for the Electrical Measurement of Partial Discharges in High Voltage Bushings and Instrument Transformers.

Scott Reed is President of MVA, a company that specializes in the oil diagnostic analysis and vacuum filling and oil processing of substation transformers throughout the United States. He received his BS in Electrical Engineering from North Carolina State University with a concentration in power. Upon graduation, he joined Baltimore Gas & Electric performing relay system protection design work and worked for 30 years servicing transformers before starting MVA. Scott has written and published various papers for the industry and is very active with the IEEE Transformer Committee, where he serves as Chair of the IEEE Subcommittee on Insulating Fluids; Vice Chair of IEEE C57.166, Guide for Acceptance and Maintenance of Insulating Liquids in Transformers and Related Equipment; and Secretary of IEEE C57.93, Installation and Maintenance of Liquid-Immersed Power Transformers.