Experimental study of the influence of BTA and Irgamet39<sup>®</sup>TM on the mineral insulation oil under thermal aging

Abstract

As we all know, BTA and Irgamet 39 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">®</sup> TM are widely used as metal passivators in electrical industry, while BTA is mainly used to inhibit the electrostatic charging tendency (ECT) of transformer oil, and Irgamet 39 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">®</sup> TM is applied to the corrosive sulfur problems in mineral insulation oils. In this paper, some oil samples that with different concentration BTA and Irgamet 39 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">®</sup> TM added were aged at 120°C, and which for 0h, 250h, 450h and 675h respectively. Subsequently, the ECT values, dissipation factor (tanδ) as well as the acid number of those aged oil samples were measured. The results show that Irgamet 39 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">®</sup> TM also has an inhibitory effect on ECT of oil, however, while compared with BTA, the dissipation factor and acid number of the aged oil samples that with Irgamet 39 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">®</sup> TM added are much larger than those with BTA or without any passivator added ones, which means that the side effect of Irgamet 39 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">®</sup> TM is larger than BTA to a certain extent.