Capacitor voltage transformer (CVT), which is with simple structure, convenient maintenance, functional diversity and high impact pressure strength, is widely used. And its capacitance and dielectric loss Angle measur...Capacitor voltage transformer (CVT), which is with simple structure, convenient maintenance, functional diversity and high impact pressure strength, is widely used. And its capacitance and dielectric loss Angle measurement is an important test on testing the insulation of the equipment. This paper is mainly to introduce and discuss one of the CVT test methods——the “self excitation method”, combined with the actual situation encountered in the work, sums up and expounds the maintenance of CVT and preventive test of influence factors.展开更多
Electroceramic calcium copper titanates(CaCu3Ti4O12,CCTO),with high dielectric permittivities（e） of approximately 105 and 104,respectively,for single crystal and bulk materials,are produced for a number of wellestab...Electroceramic calcium copper titanates(CaCu3Ti4O12,CCTO),with high dielectric permittivities（e） of approximately 105 and 104,respectively,for single crystal and bulk materials,are produced for a number of wellestablished and emerging applications such as resonator,capacitor,and sensor.These applications take advantage of the unique properties achieved through the structure and properties of CCTO.This review comprehensively focuses on the primary processing routes,effect of impurity,dielectric permittivity,and deposition technique used for the processing of electroceramics along with their chemical composition and micro and nanostructures.Emphasis is given to versatile and basic approaches that allow one to control the microstructural features that ultimately determine the properties of the CCTO ceramic.Despite the intensive research in this area,none of the studies available in the literature provides all the possible relevant information about CCTO fabrication,structure,the factors influencing its dielectric properties,CCTO immobilization,and sensing applications.展开更多
The dielectric and thermal analysis of copper doped Magnesium Hydrogen Maleate Hexahydrate single crystals are studied for the first time. The dielectric constant, loss tangent, a.c. conductivity and a.c. activation e...The dielectric and thermal analysis of copper doped Magnesium Hydrogen Maleate Hexahydrate single crystals are studied for the first time. The dielectric constant, loss tangent, a.c. conductivity and a.c. activation energy were measured with variation of frequency in the range 50 Hz to 1 MHz. Dielectric studies reveal that the present crystal under investigation show good optical quality. The melting point and final compound after decomposition were determined using the DTA/TG analysis.展开更多
文摘Capacitor voltage transformer (CVT), which is with simple structure, convenient maintenance, functional diversity and high impact pressure strength, is widely used. And its capacitance and dielectric loss Angle measurement is an important test on testing the insulation of the equipment. This paper is mainly to introduce and discuss one of the CVT test methods——the “self excitation method”, combined with the actual situation encountered in the work, sums up and expounds the maintenance of CVT and preventive test of influence factors.
基金supported by the Universiti Sains Malaysia(USM) fellowship(APEX 91002/JHEA/ATSG4001)fundamental research grant scheme(FRGS) under grant number of 203/PBAHAN/6071263
文摘Electroceramic calcium copper titanates(CaCu3Ti4O12,CCTO),with high dielectric permittivities（e） of approximately 105 and 104,respectively,for single crystal and bulk materials,are produced for a number of wellestablished and emerging applications such as resonator,capacitor,and sensor.These applications take advantage of the unique properties achieved through the structure and properties of CCTO.This review comprehensively focuses on the primary processing routes,effect of impurity,dielectric permittivity,and deposition technique used for the processing of electroceramics along with their chemical composition and micro and nanostructures.Emphasis is given to versatile and basic approaches that allow one to control the microstructural features that ultimately determine the properties of the CCTO ceramic.Despite the intensive research in this area,none of the studies available in the literature provides all the possible relevant information about CCTO fabrication,structure,the factors influencing its dielectric properties,CCTO immobilization,and sensing applications.
文摘The dielectric and thermal analysis of copper doped Magnesium Hydrogen Maleate Hexahydrate single crystals are studied for the first time. The dielectric constant, loss tangent, a.c. conductivity and a.c. activation energy were measured with variation of frequency in the range 50 Hz to 1 MHz. Dielectric studies reveal that the present crystal under investigation show good optical quality. The melting point and final compound after decomposition were determined using the DTA/TG analysis.
文摘针对变压器油运行过程中受外界因素影响而老化导致性能下降的问题,基于静电吸附原理,利用Ansoft Maxwell有限元仿真软件对“波浪”形曲面极板构造梯度非均匀电场,对变压器油中电中性杂质和带电杂质在梯度非均匀电场中的运动规律及模式进行了探究,进而研制了静电吸附净油反应器;在此基础上,设计了正交试验方案以检验该静电吸附净油反应器对油品品质的提升效果,并优化了净油反应器的工作条件。结果表明,该静电吸附净油反应器的最优工作条件为:电压12 kV、温度45℃、流速0.1 m s;经该反应器净化处理后,变压器油的介质损耗因数由0.04258降至0.00376,说明研制的净油反应器可有效提升老化变压器油的品质。
