现代稳定型氧化锌压敏陶瓷的直流老化研究进展  

Research Progress in DC Aging of Modern Stable ZnO Varistor Ceramics

作　　者：武康宁 程卓林 李柔 李建英[1] 李盛涛[1] WU Kangning;CHENG Zhuoin;LI Rou;LI Jianying;LI Shengtao(State Key Laboratory of Electrical Insulation and Power Equipment,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]西安交通大学电工材料电气绝缘全国重点实验室,西安710049

出　　处：《高电压技术》2024年第2期621-633,共13页High Voltage Engineering

基　　金：国家自然科学基金(52107027,51937008);中国博士后基金(2022M722513);电力设备电气绝缘国家重点实验室中青年基金(EIPE22310)。

摘　　要：现代稳定型氧化锌压敏陶瓷的直流老化功耗随时间持续降低,完全不同于功耗不断上升的传统老化现象,给基础老化理论和工程应用均带来了巨大挑战。这种反常的老化现象已经超出了经典离子迁移老化理论的范畴,其非阿雷尼乌斯特征也使实际状态评估和寿命预测难以开展。文中详述了现代稳定型氧化锌压敏陶瓷的直流老化及恢复特征:正向伏安特性在直流老化后存在“交叉”现象;老化过程可逆,试样充分恢复后能达到其未老化状态。离子重排(donorionredistribution,DIR)老化模型可合理解释氧化锌压敏陶瓷的直流老化现象。氧化锌压敏陶瓷的老化功耗取决于界面态消耗与耗尽层离子“U”型分布之间的竞争,前者导致功耗上升而后者有利于功耗降低。稳定型氧化锌压敏陶瓷的势垒界面态在高温、缺氧气氛等条件下不能保持稳定,其原本下降的功耗也能转变为不断上升。此外,广为应用的功耗(泄漏电流)具有显著的电压依赖特性,并不能反映氧化锌压敏陶瓷真实的老化状态,反向老化系数则有望成为一种有效的老化状态表征参数。通过深化现代稳定型氧化锌压敏陶瓷的老化现象、老化机制及状态评估的认识,本文旨在推进我国高性能氧化锌压敏陶瓷生产制造和高端避雷器发展。Power loss of modern stable ZnO varistor ceramics steadily decreases during the DC aging,which completely differs from the continuous increase in power loss of traditional instable ones.The anomalous aging phenomenon is be-yond current understandings of classic ion migration model,and the non-Arrhenius aging characteristic makes condition assessment and life prediction unavailable.This paper reviews the aging and recovering characteristics of modern stable ZnO varistor ceramics.“Crossover”phenomena of the current-voltage characteristics in the forward direction are ob-served in the aged samples.Moreover,the aging is reversible because aged samples can recovery to their initial states.These aging phenomena can be well explained by the donor ion redistribution(DIR)model,which ascribes the power loss to the competition between consumption of interface states and“U”-shape distribution of donors in depletion layers.The former leads to increase in power loss while the latter leads to decreasing power loss.Stable ZnO varistor ceramics can turn into instable ones if their interface states cannot maintain stable at higher temperatures or in oxygen-deficient atmos-phere.In addition,the widely employed power loss is voltage-dependent so that it is not an intrinsic condition assessment parameter for ZnO varistor ceramics.Instead,reverse aging coefficient is a potential assessment parameter.By deepening the understandings on the aging phenomena,aging mechanisms,and condition assessment,this paper aims to promote the manufacture of high-performance ZnO varistor ceramics,as well as the development of advanced arresters.

关 键 词：氧化锌 压敏电阻 老化 过电压保护 避雷器 状态评估 

分 类 号：TM862[电气工程—高电压与绝缘技术]