摘要
为研究6.6 MW高温超导变压器的高压磁体在雷电冲击过电压下的暂态电压响应,依据多导体传输线理论,建立了以单匝为一个单元的高频等效电路模型。利用有限元软件和编写程序求得分布参数,通过推导状态方程,并对状态变量求解,在时域内得到了各匝在雷电冲击全波电压和雷电冲击截波电压下的暂态响应。在三种雷电冲击波下高压磁体的绝缘满足安全运行的要求,首端匝间绝缘最为薄弱,雷电波发生截断可大幅降低绕组各匝最大对地电位、绕组末端的层间电压,其中在波前发生截断时可大幅降低磁体各匝间电压、层间电压,说明选用动作快速的避雷器至关重要。
The interlayer voltage of the first winding was used to study the transient voltage response of the high-voltage magnet of a 6.6 MW high-temperature superconducting(HTS)transformer under lightning impulse overvoltage.Based on the theory of multi-conductor transmission lines,a high-frequency equivalent circuit model with a single turn as a unit was established.By using finite element software and programming to obtain the distribution parameters,deriving the state equation and solving the state variables,the transient response of each turn under lightning impulse full wave voltage and lightning impulse cutoff voltage was obtained in the time domain.Under three types of lightning shock waves,the insulation of high-voltage magnets meets the requirements for safe operation.Among them,the insulation between the first end turns is the weakest.The truncation of lightning waves can significantly reduce the maximum ground potential of each turn of the winding and the interlayer voltage at the end of the winding.When the truncation occurs at the front of the wave,the voltage between each turn and interlayer of the magnet can be significantly reduced.This indicates that it is crucial to choose a fast acting lightning arrester.
作者
宋永帅
方进
廖旭
王敬宽
Song Yongshuai;Fang Jin;Liao Xu;Wang Jingkuan(School of Electrical Engineering,Beijing Jiaotong University,Beijing 100044,China)
出处
《低温与超导》
CAS
北大核心
2023年第11期15-21,共7页
Cryogenics and Superconductivity
基金
国家重点研发计划(2016YFE0201200)资助。
关键词
多导体传输线
雷电过电压
高温超导磁体
主绝缘
纵绝缘
Multi conductor transmission line
Lightning overvoltage
HTS magnet
Main insulation
Longitudinal insulation
