Studies on the Estimation of Transformer Winding Parameters

Abstract

This paper presents a new winding parameter model of UHV transformer used by On-line Least- Squares Identification Algorithm (OLSIA) to estimate winding parameters. This paper also provides the criteria to estimate the accuracy of identification model. With EMTP simulation tool, this paper establishes the model according to parameters of the first UHV power transmission system in China, simulates various situations such as UHV transformer energizing, external fault, internal fault, normal operation in the model, and demonstrates that the OLSIA based on the new transformer model is capable to estimate the winding parameters accurately in various conditions, especially in stable-state condition.