Abstract - This article describes a

Abstract - This article describes a new on-line method for capacitance and dissipation factor measurements of high voltage bushings, for recording grid transients and for partial discharge monitoring at power transformers. Failure statistics identify HV bushings as one of the major reasons for transformer failures,which motivates operators for continuous on-line monitoring of their insulation systems health. The needed accuracy for reliable detection of failures is in the range of 5 pF for capacitance and 0.1 % for dissipation factor. For reaching this goal, a relative comparison of the bushing currents of the three phases, measured at the bushing taps, does not provide sufficient accuracy due to imbalances in the network. Additionally, simultaneous ageing, as it can be anticipated for a three phase transformer, will not be detected. To overcome these shortcomings, this paper introduces an absolute method for measuring capacitance and dissipation
factor of HV bushings. Even under field conditions a measurement accuracy similar to accurate off-line power factor tests was reached. Partial discharges are an early breakdown indicator for HV dielectrics. With the measurement on the HV bushing tap, not only failure of the bushings dielectric but also of the transformer insulation system can be detected. As for off-line measurements, the discrimination between noise and true internal discharges is the key for successful diagnosis. Strategies for sensitive partial discharge measurements under disturbed on-line conditions are described, also involving measurements in the UHF range.

結果 (中文) 1:

这篇文章的抽象描述了一个新的在线方法高压套管电容和耗散因子测量、 记录网格瞬变和局部放电监测在电力变压器。故障统计识别高压套管作为变压器故障的主要原因之一其中激励经营者连续在线监测其绝缘系统健康。对于故障的可靠检测所需的精度是 5 pF 电容和损耗因数为 0.1%的范围。为达到这一目标，相对比较的套管电流的三个阶段，在衬套水龙头，测量不提供足够的准确度在网络中的不平衡。此外，同时老龄问题，因为它可以为一台三相变压器，预期将检测不到。为了克服这些缺点，本文介绍了一种绝对的方法测量电容和耗散
高压套管的因素。即使在野外条件下达成了类似于准确的离线功率因素测试测量精度。局部放电是一个早期的细分指标为高压电介质。关于高压测量与衬套点击，不只失败的介质，但还的电力变压器绝缘系统可以检测到的套管。作为离线测量噪音和真实内部放电之间歧视是成功诊断的关键。敏感的局部放电测量在线干扰条件下的战略被描述，也涉及在超高频范围内测量。

結果 (中文) 3:

摘要：本文介绍了电容和高压套管介质损耗因数测量的一种新上线的方法，用于记录电网瞬变和在电力变压器局部放电在线监测。故障统计识别高压套管是变压器故障的主要原因，这促使他们健康在线连续监测人员的绝缘系统。所需的精度对故障的可靠检测是对介质损耗电容5 pF的范围0.1%。为了达到这一目的，衬套的电流的三相比较，在套管抽头测量，不提供足够的精度，由于在网络不平衡。此外，同时老化，因为它可以预期的一三相变压器，不会被发现。为了克服这些缺点，本文介绍了用于测量电容和损耗因子的高压套管
绝对法。甚至在野外条件下，类似于精确的离线测量精度达到功率因数试验。局部放电是一种高压介质的早期故障指示器。在高压套管抽头测量，不仅对套管介质也是变压器的绝缘系统的故障可以被检测到。对于离线测量，噪声和真实之间的歧视的内部放电是成功诊断的关键。对于敏感的局部放电测量扰动在线条件下的策略进行了描述，也涉及在超高频范围内测量。