Condition assessment of cables and transformers in an aging infrastructure (and aging talent base)

摘要

The rapid industrialization that followed World War 11 required electricity to power and sustain this ensuing growth. As a result, infrastructure for electric power was put in place at an accelerating pace in subsequent decades, resulting in aging equipment. The challenges presented in taking better care of aging infrastructure include technical, lack of commensurate efforts and availability of sufficient financial resources. The gradual erosion of expertise and long general lack of hands-on electrical power equipment education in the US does not help either nor does the significantly reduced manufacturing power equipment base, as we address the aging equipment. The West Europeans and Japanese are in a better position toward this end, due to relatively robust electrical power equipment manufacturing, exporting strengths and active equipment — related graduate education. The prevailing utility business climate brought about by deregulation, competition and increasing fiscal restraints dictate that maximum and trouble-free use is made of aging infrastructure. This places focus on reliable and cost-effective diagnostic tests. While such tests have been always addressed and improved over decades, the need has never been greater, as of now. This paper covers the condition and life assessment of laminar dielectric transmission cables, power transformers and extruded cable terminations containing a dielectric fluid through Dissolved Gas Analysis (DGA). Several successful cases showing the extent of insulation damage from minor to severe as revealed by DGA-prompted equipment openings are presented. All the cable systems were re-built. This demonstrates that the techniques and lessons learned from one product can be profitably applied to another, despite lack of markedly different dielectric materials, designs and operating conditions. The general lack of hands-on equipment-related graduate education has been addressed, and ameliorative measures emphasized to aid in --taking better care of aging equipment.