Study on the Unipolar Impulse Aging Characteristics of ZnO Varistors and Their Condition Monitoring Methods. - Fan, Yongqiang; Meng, Wenkai; Tian, Xiaoyun; Yue, Yonggang; Li, Zhihui; Xu, Minxin; Xiao, Xinyan; Yang, Lanjun (Applied Sciences (2076-3417), 2025)