Dynamic thermal rating assessment of oil‐immersed power transformers for multiple operating conditions

In this article, the dynamic thermal rating assessment method of oil-immersed power transformer with multiple operating conditions is proposed, considering constraints hot spot temperature (HST), top oil temperature, losses life and maximum allowable current on-load tap changer (OLTC) or bushing, which can determine load curves under different give most sensitive to limit capacity. To improve accuracy HST estimation, estimation model also improved parameters are optimised using measured by optical fibre. Finally, several application examples studied for transformers in scenarios. The results show that normal cyclic (DTR) mainly limited when ambient high, average factor be increased 0.82 a capacity 1.23. main limiting short-term DTR OLTC bushing constraint, 1.00. both 23% 50% higher than its rated capacity, indicating still has large potential available.