Rohmanita Duanaputri, Rahman Azis Prasojo, Khusnul Islamia, Muhammad Fahmi Hakim, A. Hanifiyah Darna Fidya, H. Galuh Prawestri Citra, K. Harrij Mukti, Rachmat Sutjipto, Rahma Nur Amalia, Bustani Hadi Wijaya
The increasing adoption of rooftop solar photovoltaic (PV) systems has a significant impact on the performance and lifespan of distribution transformers. One of the main concerns is overloading, which causes a rise in transformer operating temperature, accelerating insulation degradation and reducing service life. This study aims to analyze the impact of rooftop solar PV penetration on the estimated lifetime of distribution transformers through load curve modeling and accelerated thermal aging analysis. The methodology uses actual current data from a 160 kVA transformer under various PV penetration levels (0%-100%). The load curves are converted into hotspot temperature profiles using IEC 60076-7, and Loss of Life (LOL) is calculated according to IEEE C57.91. Results show that under 20% PV penetration, LOL decreases from 0.00612% to 0.00510% per day, increasing the transformer lifespan from 45 to 53.6 years. However, higher PV penetration levels above 60% can lead to sharp load fluctuations that cause thermal cycling and reduce insulation reliability. This study demonstrates the potential of moderate PV integration to extend transformer life and provides a quantitative foundation for optimizing PV penetration in distribution networks. © 2025 IEEE.
Politeknik Negeri Malang, Electrical Engineering Department, Malang, Indonesia; PT PLN (Persero), Jakarta, Indonesia