Facts and Artifacts from IEEE 1310-2012

Silva, Marcelo Jacob da; Pereira, Fernando; Cordeiro, J. F.; Lamas, T. E.; Santos, Camila Goncalves dos; Aoki, Tamy Koreeda; Faria, E.; Hildinger, Thomas

doi:10.1109/eic.2018.8481073

Cited by 3 publications

(1 citation statement)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A recent study [7] of stator bars aged under service with 10,000 start-stops investigated the effect of laboratory load cycling according to IEEE Std 1310, equivalent to IEC 60034-18-34. No delamination was observed before load cycling.…”

Section: Introductionmentioning

confidence: 99%

Multi-stress Cyclic Testing of Roebel Stator Bars for Hydropower

Eberg

Kantar

Aakre

2022

NORD-IS

View full text Add to dashboard Cite

A multi-stress test rig was built to investigate the effect of many start-stops (load cycling) on hydropower generator insulation. To emulate real-life start-stops, stator bars were subjected to accelerated temperature cycling by circulating a 3.5 kA current and then cooling down with fans while high voltage (service voltage) was applied simultaneously to the insulation. A total of 250 load cycles were applied. Partial discharges (PD) were recorded on-line during load cycling, and after every 50 cycles, off-line dielectric loss and PD measurements were conducted. There was an apparent increase in dielectric losses after they had been subjected to a total of 250 load cycles. During load cycling, the PD level generally decreased with temperature, but there was a temporary increase in the PD activity during temperature rise and fall. This trend can be explained by different thermal expansion in copper and insulating material (epoxymica), suggesting that a stator bar that is load-cycled will be exposed to substantially higher PD levels than a stator bar under a uniform load and temperature, leading to further deterioration of the insulation quality.

show abstract

Section: Introductionmentioning

confidence: 99%