Research On The Optimal Allocation Of Distributed Generation In Distribution Network

Distributed generation supply into network is the inevitable trend of thedevelopment of power industry, but also an important aspect of the development ofsmart grid. Ensure users obtain better quality of electric energy. The connection ofdistributed generation to distribution network have an effect on the voltage quality ofthe grid, the network loss, short circuit current, static stability, power flow distributionand so on, the impact is closely related to the location and capacity of distributedgeneration. So the optimal allocation of distributed generation in distribution networkis studied.The definition of distributed generation, the generation mechanism andcharacteristics of the common distributed generation (wind power, solar power, microgas turbine) are introduced. Using IEEE33distribution network as a simulationexample, the effects of accessed distributed generation in distribution network onactive loss and quality of the electric energy are simulated base on Matlab/PSATtoolbox, the influence regularity of distributed generation access to the location andcapacity of the system are analyzed and summarized.On the basis of above analysis, established a multi-objective optimization modelfor minimum investment cost, minimum power grid loss cost, optimum voltagequality. Using PSAT to build the example model for power flow calculation. Thegenetic algorithm is described and improved. Crossover, mutation probabilitycalculation of improved adaptive are introduced. Adaptive genetic algorithm isadopted to solve the optimization model, improves global search ability andconvergence rate. Finally the example is simulated and analysied, distributedgeneration access to the system can improve the quality of voltage nodes in thesystem and reduce network loss effectively.In order to make the planning results more close to reality, considering the characteristics of time series of load, wind power and photovoltaic. Multi objectiveoptimization model is established for the investment cost of the distributedgeneration, costs of network loss, compensate cost of environment and the outagecost on the basis of timing characteristics. Finally, using the improved adaptivegenetic algorithm to solve the problem. The results show that distributed generationsaccess to the system decrease the network loss and power costs. The economy,reliability and environment protection benefit of the system are balanced excellently.