| Title |
A Study on the Electrical Dielectric Properties of Epoxy Micro Silica Composites by Moisture Absorption and Drying |
| DOI |
https://doi.org/10.5370/KIEE.2021.70.9.1312 |
| Keywords |
CT/PT; Mold Transformer; Epoxy-Micro Silica Composites; W12EST Filler; M10 Filler; Dielectric Properties |
| Abstract |
Epoxy-based microcomposites are currently used in a variety of high-voltage-based heavy electric machines (CT/PT, mold transformers, distribution insulators, etc.). Samples were prepared with three types of micro-silica-filled composites (W12est_65wt%, M10_65wt%) and epoxy prototype samples based on epoxy resin. The moisture absorption and drying properties of the three samples were evaluated. The moisture absorption process was performed until the moisture absorption of the sample was saturated in distilled water at 95°C, and the drying process was performed in a drying oven at 105°C until the moisture was saturated without any change. In the evaluation, the relationship between water absorption (M) and dielectric properties was evaluated under the conditions of steady state, moisture absorption and dry conditions. And dielectric characteristics (dielectric constant, dielectric loss and electrical conductivity) were evaluated according to the frequency change at room temperature as an evaluation environment. A large amount of water absorption resulted in a large increase in dielectric constant, dielectric loss, and electrical conductivity. In addition, it was found that the dielectric properties were restored because the dry state was based on the physical bonding with the absorbed water. |