Results 31 to 40 of about 433 (184)

Synthesis of SnO2 nanoparticles and their use in the fabrication of varistors

Revista Facultad de Ingeniería Universidad de Antioquia, 2014
SnO2 nanoparticles doped with TiO2, CoO, Nb2O3 and Al2O3 were obtained in this work using the methods of coprecipitation and polymeric precursor. X Ray Diffraction (XRD), and Scanning Electron Microscopy (SEM) were used to characterize the ceramic ...
Adolfo Alfredo Mosquera-Lozano, José Arana-Varela, Jorge Enrique Rodríguez-Páez   +2 more
doaj   +1 more source

Microstructure and Degree of Degradation of ZnO Varistors in Surge Arresters Due to Operation [PDF]

Archives of Metallurgy and Materials, 2018
The paper presents the test results for the microstructure of ZnO varistors comprising high voltage gapless surge arresters. The tests were performed on varistors produced in different periods and by various manufacturers.
P. Papliński, J. Wańkowicz, P. Ranachowski, Z. Ranachowski   +3 more
doaj   +1 more source

Aging Effects on PTCR Ceramics: SEM and C‐AFM Analysis of Electrical Conductivity and Domain Structures

International Journal of Applied Ceramic Technology, Volume 23, Issue 4, August 2026.
ABSTRACT This study examines the impact of aging on the electrical and structural properties of positive temperature coefficient of resistance (PTCR) ceramics. The presented study introduces a correlative scanning electron microscopy (SEM)/conductive atomic force microscopy (C‐AFM) approach enabling repeated, site‐specific characterization of ...
Kryštof Koller, Filip Ulč, Patrik Sokola, Veronika Hegrová, Petr Ptáček   +4 more
wiley   +1 more source

Analysis of MOA Damage Mechanism Under Multiple Strokes

Applied Sciences
Accident records from the actual operation of metal oxide arresters (MOAs) indicate that even MOA products that have passed standard tests still suffer from frequent damage.
Tao Yuan, Dengke Gao, Siyu Chen, Zhenjie Zheng   +3 more
doaj   +1 more source

Performance and Mechanism Research on ZnO Varistor Ceramics Prepared by Microwave Sintering

International Journal of Ceramic Engineering &Science, Volume 8, Issue 4, July 2026.
Microwave sintering yields superior electrical performance of ZnO varistor ceramics versus conventional sintering, clarifies its grain boundary defect regulation mechanism, and provides a low‐energy, high‐efficiency preparation strategy. ABSTRACT To solve the problems of high sintering temperature, uneven grain growth, and limited electrical property ...
Zhiyao Fu, Haocheng Liu, Bowen Wang, Zhenglong Jiang   +3 more
wiley   +1 more source

Analysis of the Anti High‐Altitude Electromagnetic Pulse Interference Ability of Relay Protection Devices

High Voltage, Volume 11, Issue 3, Page 738-750, June 2026.
ABSTRACT High altitude electromagnetic pulse (HEMP), as a steep slope and high amplitude instantaneous energy shock, has stronger coupling and greater destructive power, which can easily cause the secondary control device of the substation to malfunction.
Long Jin, Guanglong Zhou, Weidong Zhang, Zexin Zhou, Guosheng Yang, Rongrong Zhan   +5 more
wiley   +1 more source

Two basic ways to realise DC circuit breakers

The Journal of Engineering, 2019
As a key element of the DC grid, the technology of DC circuit breakers (DCCBs) still have difficulty to be widely used due to its large cost and volume. This paper studies the basic principle and its realisation methods for DCCBs.
Zheng Xu, Huangqing Xiao, Huangqing Xiao, Yuzhe Xu   +3 more
doaj   +1 more source

The Electrical Conductivity of the Lower Mantle From High‐Pressure/High‐Temperature Measurements of Pyrolite and Ten Years of Geomagnetic Observations

Journal of Geophysical Research: Solid Earth, Volume 131, Issue 4, April 2026.
Abstract Electromagnetic sounding coupled with experimental measurements of electrical conductivity (EC) can provide valuable constraints on the thermochemical state of Earth's lower mantle. Here, we report a new set of experimentally determined EC values of pyrolite, a candidate composition of the lower mantle, between 25 and 80 GPa at room ...
Charlotte Trubowitz, Motohiko Murakami, Federico Munch, Alexander Grayver, Christian Liebske, Amir Khan, Nobuyoshi Miyajima, Pinku Saha, Yoshiyuki Okuda, Georg Spiekermann, Luiz Grafulha Morales   +10 more
wiley   +1 more source

Electrical properties of ZnO varistors prepared by direct mixing of constituent phases [PDF]

Science of Sintering, 2006
Varistor samples containing different amounts of constituent phases were prepared by direct mixing of constituent phases. Detailed electrical characterization was performed to explain the influence of minor phases (spinel and intergranular phases) on ...
Žunić M., Branković Z., Branković G.
doaj   +1 more source

Study on temperature rise prediction of ZnO varistors under multiple lightning strikes based on BP neural network and microscopic

High Temperature Materials and Processes
ZnO varistors are widely used in the field of lightning protection. After being struck by lightning, ZnO varistors absorb heat, which can lead to temperature rise and even damage, posing a serious safety threat to electrical safety.
Li Chunying, Zhang Chunlong, Lv Qing
doaj   +1 more source