PV Inverter Control Within Distribution System Thermal Constraints

Abstract

The increase in distributed energy sources poses new challenges to distribution system operators. New functionalities are required to improve equipment usage and allow for more PV capacity without additional transformer hardware upgrades. Introducing the ability to manage rooftop PV systems by setting dynamic export limits for inverters is a path that some DSOs have taken. The present thesis provides an overview of such a project as has been documented in Australia. An approximate timeline is presented along with further details on project stages which may be relevant to other DSOs considering a similar approach. A detailed look is taken at the Australian lessons learned for this purpose. Indications are given on how networks may be comparable, and which reasons may be behind dynamic export curtailment requirements. In the second part of the thesis, sample data from an Upper Austrian primary substation and connected secondary substations is used to explore possible benefits unlocked by a dynamic export option. The types of data collected are explained and a brief introduction to the chosen network area is given. The availability of the required information about the network status and the process design are key parts for the introduction of a dynamic export option. Synthetic substation load profiles from 2023 are used as a basis for computing increases of PV production and their effect on curtailment necessities at network levels 4 to 6. The analysis shows a great potential for additional PV energy export into the network with increased PV capacities without the need for additional hardware upgrades, and even without increasing demand at the same time.

Date of Award	2025
Original language	English
Supervisor	Andreas Abart (Supervisor)