2.1.3.3 SUPPRESSION EFFECT OF ADDITIVES
Figure 5 depicts the effects of BTA and DBPC on the
compounds relating to the increasing process of ECT, which
originates from sulfide compounds in insulating oil [8].
Sulfoxide compounds are generated by the reaction between
sulfide compounds and peroxides, which are generated by the
oxidation of hydrocarbon compounds. Then positively
charged sulfonium ions are generated by the oxidation of
sulfoxide compounds. Sulfonium ions are considered high
ECT compounds, which charge insulating oil positively.