Disco Operation Considering DG Units and Their Goodness Factors

This paper presents a new paradigm for distribution system operation in the presence of distributed generation (DG) sources taking into consideration the goodness factor of the DG units. The proposed concept of goodness factor of DG units is based on the computation of the incremental contribution of a DG unit to distribution system losses. The incremental contributions of a DG unit to active and reactive power losses in the distribution system are termed as the active/reactive incremental loss indices (ILI). The goodness factors are integrated directly into the distribution system operations model, which is based on an optimal power flow (OPF) framework. This model seeks to minimize the distribution company's (disco's) energy costs in the short term taking into account the contribution (goodness factor) of each DG unit. Two scenarios are considered in the paper: the first scenario considers the disco to be the owner of the DG units and hence is responsible for their scheduling and dispatch, and the second scenario considers the DG units to be investor-owned. The analysis was carried out considering an 18-bus distribution network extracted from the well-known IEEE 30-bus system and a 69-bus distribution system.