Transformer Temperature Management and Voltage Control in Electric Distribution Systems with High Solar Penetration

The increasing penetration of photovoltaic (PV) systems in distribution grids can lead to overvoltage and transformer overloading issues. While voltage regulation has been extensively studied and some research has addressed transformer temperature control, there is limited work on simultaneously managing both challenges. This paper addresses this gap by proposing an optimization-based strategy that efficiently manages voltage regulation and transformer temperature while minimizing the curtailment of PV generation. In order to make this problem convex, a relaxation is applied to the transformer temperature dynamics constraint. We also provide analysis to determine under which conditions this relaxation remains tight. The proposed approach is validated through simulations, demonstrating its effectiveness in achieving the desired control objectives.