Mishra, DeepakBaral, ArijitHaque, NasirulChakravorti2023-07-192025-03-312023-07-192019-10-14D. Mishra, A. Baral, N. Haque and S. Chakravorti, "Condition Assessment of Power Transformer Insulation Using Short-Duration Time-Domain Dielectric Spectroscopy Measurement Data," in IEEE Transactions on Instrumentation and Measurement, vol. 69, no. 7, pp. 4404-4411, July 2020, doi: 10.1109/TIM.2019.2947120.0018-94561557-9662https://ieeexplore.ieee.org/document/8867958https://dspacenew8-imu.refread.com/handle/123456789/2294Utilities prefer noninvasive methods for assessing the condition of power transformer insulation. Analysis of polarization-depolarization current (PDC) is one such popular method. One such analysis involves the estimation of trapped charge released from the interfacial region of oil-paper insulation. The literature shows that such charges can be reliably used for the diagnosis of transformer insulation. However, such analysis requires a complete profile of PDC. PDC measurement (an offline technique) takes a large amount of time (several hours) to complete. The magnitude of PDC data for a larger value of time is also sensitive to changes in environmental conditions and field noise as its magnitude is low. Hence, a reliable estimation of detrapped charge may require numerous PDC measurements. This situation is not convenient for utilities as it prolongs shut down time. In this article, a method has been proposed which is capable of estimating detrapping charge using PDC data measured for a short span of time. The proposed method is tested on data collected from several real-life in-service transformers.en-USCharge carriersDielectric measurementInsulationPower transformersTime-domain analysisArticle