Enhanced thermal modeling of power transformers: A comparison of bond graph and IEEE methods considering external environmental factors

• Reliability and Operation : The paper addresses the critical role of power transformer reliability in the optimal and secure operation of electrical power systems, highlighting both operational and economic impacts. • Thermal Modeling Importance : Emphasizes the importance of thermal modeling for power transformers to prevent failures and ensure continuous power supply quality. • External Environmental Factors : The study incorporates two key external environmental factors—solar irradiation and wind flow—into the thermal models of power transformers. • Methodology : Introduces a Bond Graph (BG) method-based design for thermal modeling of power transformers and compares it with IEEE standard models and practical readings. • Real-World Implementation : The models are applied to a 5MVA, 33/11 kV power transformer at a 33 kV Substation in Sardarpura, Jodhpur, using actual operational data. • Enhanced Model Accuracy : The inclusion of solar radiation and wind flow improves the accuracy of the thermal models, as demonstrated in the comparative study. • Validation of BG Models : The effectiveness of BG-based thermal models in accurately predicting transformer behavior is validated, proving their applicability for real-world engineering scenarios. The optimal and secure operation of electrical power system is largely affected by the reliability of power transformers in operational and economic terms. The continuous monitoring of power transformer is crucial for ensuring the quality of electrical power supply. Hence, the thermal modeling of power transformer is very essential to prevent their failure. This paper aims to design thermal models of operating power transformer by considering the two external influencing parameters of solar irradiation and wind flow. This paper presents a Bond Graph (BG) method-based design of thermal models for power transformer under operating condition by comparison with the results obtained from IEEE Std. based thermal models and also with the practical readings. The models have been implemented on a 5MVA, 33/11 kV power transformer running at 33 kV Substation, Sardarpura, Jodhpur, by initially considering the input hourly dataset of load and ambient temperature. The designed thermal models were subsequently updated by integrating the impact of solar radiation and wind incident on the surface of power transformer. Comparative study of all the designed thermal models has been done that indicates improved accuracy of the model if the impact of solar radiation and wind flow are included. Also, the effectiveness of the BG based thermal models in accurately predicting the system behaviour validates their applicability for real world engineering applications.