2021 article

Assessing the Impact of High Penetration PV on the Power Transformer Loss of Life on a Distribution System

2021 IEEE PES INNOVATIVE SMART GRID TECHNOLOGY EUROPE (ISGT EUROPE 2021), pp. 323–327.

By: X. Wang n, K. DSouza n, W. Tang n & M. Baran n 

co-author countries: United States of America πŸ‡ΊπŸ‡Έ
author keywords: Hot spot temperature; loss of life; power transformer; PV penetration; thermal model
Source: Web Of Science
Added: April 4, 2022

Increasing photovoltaic (PV) systems on a distribution system impact the operation and lifetime of its components. One of the key components to be impacted is the power transformer at the substation. In this paper, we aim to evaluate the impact of high penetration PV on the lifetime of the substation power transformer. At moderate levels of PV penetration, the loading on the substation transformer decreases, and therefore this will help to prolong the lifetime of the transformer. To estimate this expected benefit, a thermal model for the transformer is used to estimate its hot spot temperature as this temperature is the main factor affecting the degradation of the transformer under normal loading conditions. To illustrate the method, a case study is given. A 10-year period is considered for transformer loss of life evaluation, where practical load growth and PV penetration scenarios are considered. The simulation is carried out on a 15 MVA transformer in the IEEE 123 bus system. Simulation results show that PV penetrations below 100% indeed prolong the transformer lifetime. However, the saved transformer lifetime is not considerable compared to the total transformer lifespan.