GIS based modelling and analysis of unbalanced LV distribution networks with distributed energy resources

Özdamar, İsmail
Conventional low voltage (LV) distribution networks are radially designed and operated in pre-defined loading limits and voltage range. However, with the increasing electricity demand and distributed generations (DGs) resulting reverse flows and under voltages, LV networks will have serious problems such as overloading and voltages out of limits. With the integration of distributed energy resources (DERs) in the system such as distributed generations, rooftop photovoltaics, battery storages, and electric vehicles into LV networks, the design and operation of low voltage networks become more complex and require a comprehensive approach including network modelling, calculation and assessment of network voltages and loadings for various scenarios. In this study, all data required for network modelling are extracted from geographic information system (GIS) and the network model, represented as bus-injection to branch current matrix (BIBC), is created by using graph theory. In addition, three phase unbalanced power flow analysis of low voltage networks with P-V buses representing distributed energy resources is developed by using modified backward/forward power flow algorithm. The results for 113-bus test case are verified by comparing the results with that of a commercial software. Main contribution of this study includes the considerable amount of decrease in network modelling effort, and the higher performance and reliability for power flow solution of unbalanced LV networks with DERs.