Analysis of power quality concerning COVID-19-related anomalies and integration of distributed energy resources

With the development of technologies and the decrease of prices, the number of end-users that decide to invest in distributed energy resources (DERs) continuously grows. Despite the improvement of financial and environmental aspects of the power system operation, a growing share of DERs can cause numerous technical challenges for distribution system operators (DSOs). Besides the integration of DERs, the novel COVID-19 disease created additional challenges for DSOs in 2020 and 2021. Due to a large number of single-phase loads and DERs, the increased consumption, the number of nonlinear loads, and power electronic devices in a distribution network, many challenges are related to power quality (PQ). In this paper, realistic case studies that consider anomalies caused by the COVID-19 pandemic and integration of DERs are presented. By using pandapower and its newly developed extension, different PQ indicators are calculated and the values of voltage magnitude, voltage unbalance factor (VUF), and total harmonic distortion (THD) are compared through different scenarios. In addition, the impact of a transformer’s vector group on the PQ indicators’ propagation through the observed distribution network is analyzed. In a conclusion, the optimal vector group, that successfully mitigates or at least decreases the values of PQ indicators and their propagation is proposed.