Articles
All articles | Recent articles
Improved Direct-Current Aging Stability and Suppressed Leakage Current of Zinc Oxide Varistors by Co-doping with Boron, Gallium, and Yttrium
Kuan Cheng1, Weiqing Wang1, Dongji Liu1, Qingyun Xie2, Yuanxiang Zhou3, Hongfeng Zhao1
1 School of Electrical Engineering, Xinjiang University, Urumqi 830047, China
2 Xidian Surge Arrester Co., Ltd, Xi'an, Shanxi, 710200, China
3 State Key Lab of Power Systems, Department of Electrical Engineering, Tsinghua University, Beijing 100084, China
received March 24, 2020, received in revised form June 7, 2020, accepted June 17, 2020
Vol. 11, No. 2, Pages 111-116 DOI: 10.4416/JCST2020-00008
Abstract
The effect of B3+, Ga3+ and Y3+ co-doping on the microscopic and electrical properties of ZnO varistors is studied. Co-doping with multiple ions greatly improves the comprehensive performance of the ZnO varistors. The doped Ga3+ increases the acceptor concentration, raises the barrier height, and inhibits the increase of leakage current. Y3+ increases the voltage gradient by limiting the growth of grains. B3+ improves the resistance of ZnO varistors to direct-current aging. The varistor with a B3+ content of 0.2 mol% achieves a voltage gradient of 450 V/mm, leakage current of 0.54 A/cm2, and a nonlinear coefficient of 79. Accelerated aging experiments carried out for 1 000 h at 0.9 U1mA and 115 °C give an aging coefficient of 0.027. This research illustrates the ability of cation co-doping to improve the protection effect of metal oxide arrestors and the stability of power systems that operate at ± 1100 kV.
Download Full Article (PDF)
Keywords
Ceramic, varistor, electrical properties, DC aging, aging coefficient
References
1 Arcia-Garibaldi, G., Cruz-Romero, P., Gómez-Expósito, A.: Future power transmission: visions, technologies and challenges, Renew. Sustain. Energy. Rev., 94, 285 – 301, (2018).
2 Liu, Z.H., Zhang, F.X., Yu, J., Gao, K.L., Ma, W.M.: Research on key technologies in ±1100 kV ultra-high voltage DC transmission, High Volt., 3, 279 – 288, (2018).
3 Clarke, D.R.: Varistor ceramics, J. Am. Ceram. Soc., 82, 485 – 502, (1999).
4 Liu, F., Xu, G., Duan, L., Li, Y., Li, Y., Cui, P.: Influence of B2O3 additives on microstructure and electrical properties of ZnO-Bi2O3-Sb2O3-based varistors, J. Alloy. Compd., 509, 56 – 58, (2011).
5 Gupta, T.K.: Effect of minor doping on the high current application of the ZnO varistor, Ferroelectrics, 102, 391 – 396, (1990).
6 Imai, T., Udagawa, T., Ando, H., Tanno, Y., Kayano, Y., Kan, M.: Development of high gradient zinc oxide nonlinear resistors and their application to surge arresters, IEEE. T. Power. Del., 13, [4], 1182 – 1187, (1998).
7 Chen, Q.H., He, J.L., Tan, K.X., Chen, S.M., Yan, M.Y.: Influence of grain size on distribution of temperature and thermal stress in ZnO varistor ceramics, J. Sci. China Ser., E45, [4], 337 – 347, (2002).
8 Gupta, T.K.: Application of zinc oxide varistors, J. Am. Ceram. Soc., 73, 1817 – 1840, (1990).
9 Cheng, L.H., Li, G.R., Yuan, K.Y., Meng, L., Zheng, L.Y.: Improvement in nonlinear properties and electrical stability of ZnO varistors with B2O3 additives by nano-coating method, J. Am. Ceram. Soc., 95, 1004 – 1010, (2011).
10 Li, C.Y., Lin, C.J., Yang, Y., Zhang, B., Liu, W.D., Li, Q., Hu, J., He, S., Liu, X.L., He, J.L.: Novel HVDC spacers by adaptively controlling surface charges – Part II: Experiment, IEEE Trans. Dielectr. Electr. Insul., 25, [4], 1248 – 1258, (2018).
11 Zhao, H.F., He, J.L., Hu, J., Chen, S.M., Xie, Q.Y.: High nonlinearity and low residual-voltage ZnO varistor ceramics by synchronously doping Ga2O3 and Al2O3, J. Mater. Lett., 164, [1], 80 – 83, (2016).
12 He, J.L., Liu, J., Hu, J., Long, W.C.: AC ageing characteristics of Y2O3-doped ZnO varistors with high voltage gradient, J. Mater. Lett., 65, [17], 2595 – 2597, (2011).
13 Jiang, S.L., Xie, T.T., Zhang, H.B., Guo, T., Huang, Y.Q.: Study on the ZnO-Based ceramic films for low-voltage varistors with high stability, J. Electroceram., 21, [21], 528 – 531, (2008).
14 Wurst, J.C., Nelson, J.A.: Lineal intercept technique for measuring grain size in two-phase polycrystalline ceramics, J. Am. Ceram. Soc., 55, [2], 109 – 111, (1972).
15 He, J.L., Hu, J., Lin, Y.H.: High voltage gradient ZnO varistor ceramics with rare earth dopants, J. Sci. China Ser., E39, 109 – 113, (2009).
16 Zhao, H.F., He, J.L., Hu, J., Chen, S.M., Xie, Q.Y.: High nonlinearity and high voltage gradient ZnO varistor ceramics tailored by combining Ga2O3, Al2O3, and Y2O3 dopants, J. Am. Ceram., 99, [3], 769 – 772, (2016).
17 Gupta, T.K., Carlson, W.G.: A grain-boundary defect model for instability/stability of a ZnO varistor, J. Mater. Sci., 20, 3487 – 3500, (1985)
18 Gupta, T.K.: Microstructural engineering through donor and acceptor doping in the grain and grain boundary of a polycrystalline semiconducting ceramic, J. Mater. Res., 7, [12], 3280 – 3295, (1992).
19 Bernik, S., MačEk, S., Ai, B.: The characteristics of ZnO-Bi2O3-Based varistor ceramics doped with Y2O3 and varying amounts of Sb2O3, J. Eur. Ceram. Soc., 24, 1195 – 1198, (2004).
20 He, J.L., Zeng, R., Tu, Y.P., Han, S.W., Cho, H.G.: Aging characteristics and mechanisms of ZnO nonlinear varistors, in: Proceedings of the 6th International Conference on Properties and Applications of Dielectric Materials, June 21 – 26, 2000, Xi'an, China.
21 Eda, K., Iga, A., Matsuoka, M.: Degradation mechanism of non-ohmic zinc oxide ceramics, J. Appl. Phys., 51, [5], 2678 – 2684, (1980).
22 Glot, A.B., Mazurik, S.V.: Nonlinear electrical properties of zinc oxide ceramics with B2O3 additions, Inorg. Mater., 36, [6], 636 – 639, (2000).
Copyright
Göller Verlag GmbH