Investigation of dielectric behavior of water and thermally aged of XLPE/BaTiO₃composites in the low-frequency range

Abstract

Cross-Linked Polyethylene (XLPE) is widely used as insulation in electrical engineering, especially as cable insulation sheaths. In order to improve the dielectric properties susceptible to be modified under the effects of thermal aging and water in an absorption environment, polymers are mixed with ceramics. In this paper, the influence of barium titanate (BaTiO3), on the dielectric properties of XLPE has been studied. Dielectric parameters have been measured using an impedance analyzer RLC (WAYNE KERR 6420 type). Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy and X-ray diffraction were used as characterization techniques. The study has been carried out on two samples of XLPE. A pure sample of each were studied as a unloaded samples to be compared with samples of 5%wt, 10%wt, 15%wt and 20%wt. BaTiO3 loaded XLPE. Afterwards, the composites were subject to humidity and to thermal aging. The incorporation of BaTiO3 1[Formula: see text]C does not modify the crystallinity and morphology of the XLPE and 2[Formula: see text]C reduces the space charges therefore the dielectric losses. [Formula: see text], [Formula: see text] and loss index are measured. Frequency response analysis has been followed in the frequency range (20–300 Hz). Experimental results show well that BaTiO3 as nano-filler improves the dielectric properties of XLPE but in excessive content can drive to the cracking and therefore to absorption of water.

An Experimental Study of the Dielectric Parameters of PVC Nano-Composites under Corona Conditions

“…As demonstrated in Figure 4, for a frequency of 100Hz, the values of Ɛ r for BaTiO 3 , TiO 2 , CaCO 3 , and Al 2 O 3 decrease by approximately 57%, 50%, 35%, and 37%, respectively, compared to the value of Ɛ r for pure PVC prior to aging. These findings are in agreement with the findings of [13,25,33], and can be validated through (1) [1]:…”

“…This result is consistent with previous research on BaTiO 3 doped PVC [28], where a peak in the dielectric constant curve was observed around 50Hz, and a second peak was detected at 500Hz. The same relaxation phenomena were also observed in our previous work [1,28] and in [29]. Specifically, the first and 0,1 1 10 0,00E+000 second relaxation phenomena occurred at low frequencies around 50 and 500Hz, respectively, as shown in Figures 4 and 5.…”

“…Incorporating nano fillers into the PVC matrix allows for the modification of the composite's dielectric parameters. These values are dependent on the type of filler, the integration rate, and the dielectric parameters of the fillers themselves [1,21,35]. Specifically, in our study, the dielectric constant (Ɛr) increased and the loss tangent (tgδ) decreased as the nano-filler content increased, as shown in Figures 4 and 5.…”

“…Polymeric electrical insulation is subjected to electric fields and thermal stresses in distribution power lines, making it crucial to develop new insulation coordination procedures to improve electric insulation parts in substations. In recent years, nanotechnology has been increasingly utilized in the synthesis of polymer-nano-composites, which have shown improved mechanical, electrical, and chemical properties [1][2][3][4]. Dielectric spectroscopies in time and frequency domains are useful tools for evaluating and diagnosing electrical insulation and understanding the dynamics of complex solid polymer systems [5][6][7].…”

MgO Effect on The Dielectric Properties of BaTiO3

“…Barium titanate (BaTiO 3 ) is considered one of the most promising systems for applications in electro-optic devices, memory devices, temperature sensors, time delay circuits, current limiters, current stabilizers and capacitors [1]. BaTiO 3 is used as doping in other electrical engineering applications such as varistors [2] and in polymer composites like cable insulation sheaths [3,4]. The dielectric and ferroelectric properties of BaTiO 3 can be efficiently controlled by dopant addition.…”