Research On Distribution Network Optimal Reconfiguration With Distributed Generation

Due to the expansion and application of new technology, the structure of the distribution network is more and more complex. At the same time, as the world increasingly tense situation of energy, the use of renewable energy and distributed generation (DG) technology are proved to be one of the main researches in the power industry. In this background, the reserch on optimization of distribution network with DG is important theoretical and practical significance.Optimal power flow (OPF) is to optimize the allocation of resources and the effective method to improve system efficiency. So reaserch on optimization of distribution network including DG is very important, which can reduce the distribution network loss, improve voltage quality, restore power service and improve system efficiency, etc. The main work is as follows:1. Based on the OPF model, the accurate radial constraint is introduced. A mathematical model of distribution network reconfiguration based on optimal power flow is established. The model not only ensures the radial operation of the system but also minimizes the active network loss.2. On the basis of the above model, the DG is considered as generator to join the distribution network. So, the generation output and location constraints are added into the model. Through the simulation of different situations that the interconnection of DG in fixed node and optimal node, we can get corresponding optimizing results.3. This paper presents a model of service restoration of the distribution network with DG, which can rule out general line fault through network reconfiguration directly.While the failure occurs in the line connected to grid, we can use network reconfiguration to get optimal islands, then all or part of the loads can be supplyed by distributed generations.4. On the basis of the islanding operation, a model that distribution network with DG to restore maximum power supplied area is established. Due to the limit of the distributed generation output, this model achieves the most widespread to restore power under the condition of ensure the safe and stable operationIEEE-33node, PG&E-69node and119nodes system are employed to validate the effectiveness of the presented method.