Battery Optimization and Voltage Management Methods for Distributed Energy Generation with Clustered Battery Storage

Abstract

This thesis studies and assesses methods of battery control for residential systems with PV and battery and the management of voltage level in low voltage distribution networks. The University of Auckland’s Power System Group has partnered with Vector to monitor and analyse the different trial currently in progress across the Auckland region. Monitoring these different trials will provide information on the impact that PV and battery have on the distribution network and ensure the health of the system. This thesis will focus on the Kupe Street trial which involves 30 houses with PV and clustered battery. The information from the analysis of Kupe Street will be beneficial to Vector for developing plans to correct current problems in the system and develop plans to prevent future occurrences in both Kupe Street and new projects. This study is divided into 3 different parts. The first part looks into the different battery control methods and low voltage control with DG that are currently being studied. This will provide information on how to formulate a battery charging and discharging schedule and methods for mitigating the effects of a grid disturbance such as over or under voltage. In the second part is the monitoring and analysis of the different Vector trials. The main focus will be on Kupe Street while only the voltage levels of the Sun Genie Trials are monitored. The voltage monitoring of Sun Genie ensures that the system is working fine and is not causing any disruptions to the grid. The Kupe Street analysis will involve comparing the simulated data from a model created by Katherine Murphy and the data collected from the site. The voltage bands of the Kupe Street will be monitored as well to ensure that there are no voltage band violation. Load shedding analysis is also carried for Kupe Street to demonstrate the effects of installing a system with PV and battery. Using the data collected from the monitoring and analysis and literature reviews in the first part, a method of battery optimization and scheduling and methods to reduce the impact of over and under voltages that could occur will be proposed. In the last part of the thesis, the issues that arose during the Kupe Street Trial will be addressed. The cause and effects of these issue will be considered and the methods of resolving these issues are mentioned. Also, the different data acquisition tools used throughout this project are discussed. The data management software for Sun Genie is looked into and the development of a download tool for Solar Edge is discussed.