Simplified Modeling of Low Voltage Distribution Networks for PV Voltage Impact Studies

Abstract

Distributed generation is increasingly being integrated into distribution networks worldwide, presenting new challenges for network operators and planners. In particular, the introduction of photovoltaic (PV) generation at the low voltage (LV) level has highlighted the ongoing need for more extensive and detailed modeling to quantify the full extent and nature of potential impacts. While a number of approaches have been developed to address the size of this problem, the most accurate and comprehensive approach is to carry out simulations for the entire network across multiple scenarios. However, this task is computationally complex and requires significant amounts of data. To address this challenge, this paper presents a simplified and computationally efficient methodology based around a two-bus equivalent model, which may be used to estimate the maximum voltage in an LV area due to PV generation over time. The developed model is validated against a full three-phase power flow approach for a real-world distribution network comprising 10 213 LV network areas. Furthermore, to highlight its utility, the model is used in a case study examining the effectiveness of reactive power injection for mitigating overvoltage due to PV generation.