Research Of Distribution Network Optimal Operation With Distributed Generation Based On Grid Computing

In our country, energy conservation and emission reduction is promoted with great effort, and electric power market reform is also under advancement. Under this environment, DG (Distributed Generation) attracts more and more attention. DG causes the distributed network to turn from simple radial structure to complex structure containing a lot of power sources. The position and capacity as well as the operation of DG have great impact on node voltage,power flow,short-circuit current and losses of the network. Therefore, exploration on how to apply DG in the optimal operation of distribution network is meaningful.The problems studied in this paper mainly contains: analysis and calculation on the operation value of wind power; optimal allocation of DG in distribution network and its parallel computation.First, this paper studies on four main types of DG: wind generation, photovltaic generation, micro turbine generation and energy storage battery. According to their different characteristics, stable models for each one is constructed, and unified model is promoted which is used in stable analysis. Then, in the view of grid computing, this paper introduces parallel strategy of Ant Colony Algorithm which make foundation for the study of parallel computing under grid.In order to provide more reasonable decision making for the DG allocation and operation, the problem how to accurately calculate the operation value of DG should be firstly solved. As wind generation has great uncertainty on output, by using stochastic simulation, a complete cost and benefit analysis has been conducted in this paper on grid connected wind generation and the distribution network fuel-save dispatch model is constructed. On this basis, an example is given to demonstrate the impact of manage mode,connect position,wind forecast error,electricity price,fuel price factors on operation value of wind power.Finally, based on the work described above, the optimal allocation problem of DG under multiple load levels in distribution network is investigated. A new bilevel programming model that considers DG participating in fuel-save dispatching is proposed. The upper level aims at maximizing the operation value of DG by determining the site and size of DG and energy storage; the lower level determines DG output by simulating optimal fuel-save dispatch in distribution network including energy storage. A hybrid algorithm which combines ant colony algorithm with sequence linear programming to solve this model is constructed. In order to decrease the computation time, a parallel ant colony algorithm is implemented under grid computing. Improvement on how to choose the partner, the context, the time interval of information exchange between the processors is made, and an adaptive parallel ant colony algorithm is proposed. Simulation results show that the DG capacity and operation value is greatly enhanced with the built model, and the calculation speed and searching efficiency can be improved by parallel algorithm. The adaptive parallel algorithm is also helpful to maintain population diversity and avoid pre-maturity.