Optimal Locating And Sizing Of Distributed Generations In Distribution Network

In recent years, with the prominence of energy and environmental issues and the matures of distributed generation(DG) technology, more and more distributed generations have been embedded into distribution network, which has dramatically changed the structure, operation, and control of distribution system. The reasonable access position and the appropriate access capacity of distributed generation are crucial.Two problems exist in the traditional researches. 1) The improvement of distribution network reliability, the reduction of power supply cost of unit load and random fluctuation nature of DG are failed to be considered at the same time by traditional method. The effects of DG on economy of distribution network are not fully considered in these papers. 2) Most of the researches on distributed power plan use deterministic methods. Since wind turbine and photovoltaic power generation have different probability characteristics in different time, the complementarity of them are failed to be took into consideration in these researches.A novel approach is proposed to address the optimal locating and sizing of distributed generation in distribution network. The main work of this paper is as follows. First,at the basis of building timing characteristics models and analyzing classic scenarios of DG and loads, probabilistic load flow computation based on semi-invariant is applied in order to deal with timing calculation problem in the objective function. Then the effects of DG on economy of distribution network are analyzed comprehensively. Based on the credit capacity theory, the improvement of distribution network reliability is turned into the reduction of power supply cost of unit load. The effects of DG on distribution network income by the sale of electricity and transmission losses are also analyzed comprehensively. Then a planning model which takes the cost of unit benefit as an objective function is developed. And a specific method to solve the problem of optimal locating and sizing of distributed generations in distribution network is proposed. Particle swarm optimization combined with probabilistic load flow computation is applied to solve the optimization planning. Penalty function is used to deal with the constraint conditions. Then the optimal solution obtained by adaptive particle swarm optimization is the final planning scheme. At last, the validity and accuracy of this assessment approach is verified by the simulation on the model of the calculation example.