메뉴 건너뛰기
소속 기관 / 학교 인증
인증하면 논문, 학술자료 등을  무료로 열람할 수 있어요.
한국대학교, 누리자동차, 시립도서관 등 나의 기관을 확인해보세요
(국내 대학 90% 이상 구독 중)
고객센터 ENG
주제분류

논문 기본 정보

저자정보
(Hanyang University) (Hanyang University) (Hanyang University) (Hanyang University) (Hanyang University)
저널정보
대한전기학회 전기학회논문지 전기학회논문지 제75권 제10호
오류 신고하기

피인용 0

검색

    초록·키워드

    HVDC converter transformers are subjected to complex electrical stresses because AC and DC voltage components coexist on the valve winding. This study investigates time-dependent electric-field redistribution in the oil-pressboard insulation of a ±525 kV VSC-HVDC converter transformer under an earth-referenced AC/DC superimposed valve-winding voltage obtained from system-level steady-state analysis. A time-dependent finite-element electric-field analysis was performed in COMSOL Multiphysics using fixed electrical properties of insulating oil and pressboard. The electric field was initially concentrated in the oil channels but gradually shifted toward the pressboard barriers due to Maxwell-Wagner field redistribution. The Maxwell-Wagner relaxation times for the different barrier configurations ranged from approximately 3.49 to 5.79 s, and the 50 s analysis period covered a period in which the field variation became gradual following the major redistribution. With the inter-barrier oil-gap thickness fixed at 2 mm and the total insulation distance maintained at 110 mm, the pressboard barrier thickness and number were varied, thereby changing the overall pressboard fraction. At 50 s, the maximum pressboard electric field decreased from 16.9 to 10.8 kV/mm, corresponding to a reduction of approximately 36%, while the oil-channel electric field remained within a relatively similar range despite changes in the overall insulation configuration. These results highlight the need to consider time-dependent electric-field redistribution caused by the sustained DC component of AC/DC superimposed voltage in HVDC converter-transformer insulation design.

    최근 본 자료 전체보기