Study on the paper ageing in transformer oil using furfural concentration as indication

Abstract

详细分析了 310台线路变压器的油样。结果表明 :尽管运行时间较长的变压器糠醛浓度较高 ,但随运行时间而加大的趋势不明显。糠醛浓度发生偶然性和阶跃性增加的原因一般为变压器内部故障引起的局部过热或变压器过负荷引起的整体过热。计算机仿真结果和实测的糠醛浓度与运行时间的关系曲线相当吻合。 This paper reports on the analysis of data on the concentration of furfural in oil samples from 310 transmission transformers. The data showed that while high furfural concentrations (FC s) tended to occur in older transformers, there was no distinct trend. This together with the lack of an upward tendency for the FC in cases where two readings were taken several months apart, indicated that the deterioration in paper strength and the associated increase in FC, occur in occasional and discrete steps. These step changes are presumed to be due either to internal faults causing extreme local overheating, or to overloading of the transformer causing general overheating. A simulation based on the these criteria gave a similar pattern of FC versus service age.