소결시간에 따른 ZPCCD계 바리스터의 전기적 특성 및 안정성 |
남춘우, 박종아, 유대훈, 서형권1 |
동의대학교 전기공학과 1(주)에이피케이 |
Electrical Properties and Stability of ZPCCD-Based Varistors with Sintering Time |
Choon-Woo Nahm, Jong-Ah Park, Dea-Hoon Yoo, Hyoung-Kwon Suh1 |
Department of Electrical Engineering, Dongeui University 1APK Co. Ltd |
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ABSTRACT |
The electrical properties and stability of the varistors composed of ZnO-Pr$_{6}$O$_{11}$-CoO-Cr$_{2}$O$_{3}$-Dy$_{2}$O$_{3}$ system were investigated with sintering time in the range of 1$~$3 h at 1350$^{circ}C$ . As the sintering time was increased, the varistor voltage and leakage current increased, but the nonlinear exponent decreased. The varistors sintered for 1 h exhibited excellent nonlinearity, with a nonlinear exponent of 55.3 and a leakage current of 0.1 $mu$A, whereas presented relatively low stability. The varistors sintered for 2 h exhibited not only high nonlinear exponent of 46.3, low leakage current of 0.3 $mu$A, low dielectric dissipation factor of 0.0431, but also the highest stability, in which the variation rates of varistor voltage, nonlinear exponent, leakage current, dielectric constant, and dielectric dissipation factor were -3.0$%$, -4.1$%$, +3056.2$%$, +5.1$%$, and -12.5$%$, respectively, after DC accelerated aging stress state of 0.95 V$_{1ma}$/150$^{circ}C$/24 h. On the whole, the nonlinearity and stability of these varistors are greatly affected by the sintering time. |
Key words:
Varistors, Nonlinearity, Stability, DC accelerated aging stress |
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