Research On The Reactive Power Control Of Distributed Generation System

Distributed generation (DG) is a new technology with nice prospect, which is always connected with distribution system. So the research on reactive power control of distributed generation system is valuable in theory and in practice. The content of this paper are arranged as follows:Firstly, the impacts of DG on distribution network such as loss and node voltages, is researched. Power flow method is applied to obtain the voltage profile before and after interconnecting DG sources. The general operation guideline is revealed after several simulations where the DG sources' output and location change. Based on ideal and practical models of distribution network, the author concludes the DG influence on power loss, considering two related factors: the DG sources' capacity and location condition.Secondly, a reactive power optimization algorithm including DG sources based on genetic algorithm is proposed. The corresponding particular model is built which takes into the minimum network loss and node voltage constraint. Genetic algorithm is used in reactive power optimization. The simulation examples show that the validity and effectiveness of the proposed algorithm in reducing network losses and improving the voltage profiles.Lastly, the grid-connected inverter of distributed generation model is set up. To achieve the reactive power regulation independently, the active and reactive power decoupled control is researched. Then the simulation and experiment results were also presented.The research on reactive power control of distributed generation is of certain value to the DG application in practice. The purpose is to achieve the positive applications, lighten the negative affection of DG and make the system more efficient and reliable.