Assessing the Impact of Distributed Generation on Power Distribution Systems

Distributed generation (DG) has gained significant interest over the last few years and is a key component of future power distribution systems (PDSs) due to current decarbonization goals worldwide. Despite the advantages offered by DG, several technical challenges can result from the inappropriate integration of DG in existing distribution networks. Therefore, to ensure that distribution network performance can meet the expected technical requirements, it is essential to assess DG impacts on PDSs and address the challenges these impacts imply. Here we propose a methodology for such an assessment that considers the photovoltaic (PV) system as a DG and includes the characterization of the solar irradiation resource and a rooftop PV hosting capacity estimation. Monte Carlo simulation was used to obtain a PV system integration scenario in the PDSs under study, in which the uncertainty levels associated with variables such as installation location and PV system size are considered. In addition, a steady-state analysis was carried out through power flow calculation. The proposed methodology was evaluated in a feeder operated by ELEPCO S.A. in Ecuador and shown to be effective. Moreover, the assessment indicated that even low PV penetration levels can lead to reverse flows and increased power losses in strongly unbalanced PDSs.