摘要
为了验证国产天然酯在500 kV变压器中应用的可行性,本文针对一台334 MVA/500 kV单相自耦型国产天然酯变压器,对其在雷电冲击下的电场与温升特性开展仿真计算与试验验证。电场仿真计算结果表明,天然酯变压器的电场分布更加均匀,变压器在负极性雷电冲击下的绝缘裕度为1.27,相较矿物绝缘油的1.49有所下降,但仍满足要求;该变压器可顺利通过各项绝缘例行试验。在热性能方面,该变压器的热点位于中压绕组从上到下第4饼区域,热点温升仿真计算结果为75.2 K;温升试验外推热点温升为66.1 K,计算值和试验值均未超过温升限值。同时在通过温升试验确定热点温度时应考虑适当增大热点因子的取值,以反映天然酯变压器与矿物油变压器散热性能的差异。本研究首次验证了国产天然酯绝缘液用于500 kV超高压变压器的可行性,为国产环保绝缘材料在超高压电力设备中的应用推广提供了重要参考。
To verify the feasibility of applying domestic natural esters in 500 kV transformers,the electric field and temperature rise characteristics of a 334 MVA/500 kV single-phase autotransformer filled with a domestic natural ester were simulated and verified under lightning impulse conditions.The electric field simulation results show that the field distribution of the natural ester transformer is more uniform.Under negative lightning impulse,the insulation margin of the transformer is 1.27,which is lower than 1.49 of the mineral insulating oil,but still meets the requirements.The transformer can successfully pass all relevant insulation routine test items.In terms of thermal performance,the hotspot of the transformer is located in the fourth disc from top to bottom of the medium-voltage winding.The simulated hotspot temperature rise is 75.2 K,while the extrapolated value from the temperature rise test is 66.1 K,both the calculated and test values are within the specified thermal limits.It is also recommended to adopt a higher hotspot factor when estimating hotspot temperatures by temperature rise test to reflect the differences in cooling performance between natural ester transformer and mineral oil transformer.This study presents the first engineering validation of applying a domestic natural ester insulating fluid in a 500 kV ultra-high voltage transformer,providing important technical reference for the application and promotion of domestic environmentally friendly insulating materials in ultra-high voltage power equipment.
作者
唐桢馥
宋浩永
尹可盈
王远
胡伟
黄青丹
徐阳
TANG Zhenfu;SONG Haoyong;YIN Keying;WANG Yuan;HU Wei;HUANG Qingdan;XU Yang(State Key Laboratory of Electrical Insulation and Power Equipment,Xi′an Jiaotong University,Xi′an 710049,China;Guangdong Power Grid Co.,Ltd.,Guangzhou 510410,China;TBEA Hengyang Transformer Co.,Ltd.,Hengyang 421007,China)
出处
《绝缘材料》
北大核心
2025年第8期19-27,共9页
Insulating Materials
基金
南方电网公司科技项目(GZHKJXM20190096)。
关键词
天然酯
超高压变压器
绝缘裕度
温升
natural ester
ultra-high voltage transformer
insulation margin
temperature rise
