Study on Condensation of the Moisture in Current Transformers with Current Flow Considering Sharp Temperature Decrease
On-site experience suggests the possibility of condensation of the moisture in Current transformers (CTs) with initial moisture content lower than the Chinese National Standard. In order to verify such possibility, the relationship between moisture content and ambient temperature in a typical 110 kV CT is studied. The positive correlation of ambient temperature and moisture content without current flow is clarified, and the relationship of moisture content and current RMS value is studied. Increase in current results in increase of moisture content, and the longer the duration of operation, the larger the moisture content. The possibility of frost condensation of the moisture with sharp ambient temperature decrease has been confirmed with initial moisture content lower than the Chinese National Standard.
Prasad Yarlagadda and Yun-Hae Kim
Z. H. Yan et al., "Study on Condensation of the Moisture in Current Transformers with Current Flow Considering Sharp Temperature Decrease", Applied Mechanics and Materials, Vols. 241-244, pp. 322-327, 2013