There is an enormous opportunity for the investigation in the area of the thermal modeling of the power transformers. This is generally done by evolving computational thermal models using suitable software platforms. These thermal models are primarily based on Institute of Electrical and Electronic Engineers and International Electro-technical Commission guidelines. The heat transfer studies are done by determining the maximum temperature, also known as hot-spot temperature inside the power transformer. This paper presents a differential equation approach to design a model for determination of hot-spot temperature while considering variation in load and ambient temperature. The modeling is carried out using MATLAB programming software for the design of thermal model of power transformer. This approach is appropriate for real-time monitoring of hot-spot temperature in power transformers under continuous outdoor operation. The proposed method is confirmed using real-time data gathered from a 500MVA power transformer under operation at 400kV grid substation, Kankani, Jodhpur (Rajasthan, India).

thermal modeling, hot-spot temperature, differential equation, ambient temperature, real time monitoring.

Received: January 4, 2022; Accepted: February 23, 2022; Published: March 15, 2022

How to cite this article: Vinit Mehta and Jayashri Vajpai, Time-varying ambient temperature and variable electrical load based thermal modeling of power transformer using differential equation approach, JP Journal of Heat and Mass Transfer 26 (2022), 91-109. http://dx.doi.org/10.17654/0973576322015

This Open Access Article is Licensed under Creative Commons Attribution 4.0 International License

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