The Distribution Network Reliability And Economy Study Considering The Distribution Generation

Nowadays, with the growing development and application of Distributed Generation (DG), the proportion of DG in power system becomes an increasingly large. The application of DG in large power grids has brought many benefits, such as enhancing power quality, improving peak load, helping to achieve the optimum distribution of resources, etc.. In all, the DG is the optimal choice for long-term energy development, environment protection, and peaceful society.With the penetration of DG into distribution system, the structure and operational way of system are changing, the reliability assessment model is also different with the traditional one when DG is operating in island mode. In this paper the impact of DG parallel operation on distribution network reliability is studied. Considering the uncertainty of original parameters in both components and loads of distribution system, the indices for the evaluation of distribution network reliability with DG parallel operation based on the interval computation are calculated. Taking IEEE-RBTS 6 bus distribution system for example, the impact of different model on distribution network reliability is analyzed by comparing with distributed generation no considered, treated as the generators with rated capacity as well as the generators with the multiple operational states, thus the effect of DG parallel operation in improving distribution network reliability is verified. The improvement of the distribution system reliability is also faced with economic decisions. The paper evaluates the reliability and economy of distribution system containing distributed generation employing cost-benefit method, and establishes objective function considering distributed generation's environmental benefits.The objective function gets the balance between economy and reliability effectively and coordinates the interests of the supplier and users both sides. Taking IEEE-RBTS Bus6 distribution system for example, the feasibility of DG parallel operation and the value of economics assessment of the reliability are analyzed to aim at different capacity and different address of different types of DG, which lay the foundation of optimal planning of the supplier and users.