Homotopy-enhanced Robust Power Flow Methods For General Distribution Networks With Distributed Generators: Method And Analysis

Recent years have witnessed a growing trend towards the development anddeployment of distributed generation (DG). This trend in combination with theemergence of a number of new distribution generation technologies has profoundlychanged the traditional paradigm of power industry in distribution networks. Thewidespread use of dispersed generations in utility distribution feeders is indeedincreasing. With this tendency, it is necessary to develop analysis tool for assessingimpacts of dispersed generations on distribution networks.One challenging task for the steady-state of distribution networks with DGs isthe issue of power flow convergence. In this paper, analysis of divergence problemsassociated with the Implicit Z-bus method is performed. Implicit Z-bus distributionpower flow method may encounter divergence problems when applied to distributionsystems with distributed generators (DGs) modeled as P-V nodes.The issue of power flow divergence when dispersed generations are modeled asP-V nodes needs to be addressed. To address this issue, this paper presents ahomotopy-enhanced robust power flow method. Several numerical aspects of theimplementation were discussed. To evaluate its reliability and effectiveness, theproposed method is applied to IEEE13-bus distribution network and the IEEE8,500-node test system. The evaluation results were very promising. It has soundtheoretical basis and is applicable to large-scale distribution networks.