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

TL;DR

This paper presents an optimization strategy for simultaneously managing voltage levels and transformer temperatures in distribution systems with high solar PV penetration, ensuring system safety and efficiency.

Contribution

It introduces a convex relaxation approach to jointly control voltage and transformer temperature, filling a gap in existing research.

Findings

Effective voltage and temperature regulation demonstrated in simulations

Relaxation remains tight under certain conditions

Reduces PV curtailment while maintaining system stability

Abstract

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.