Research On Reactive Power Optimization In Distribution Network Containing Distributed Generation

The reactive power optimization of distribution network is the important measure to ensure the economic operation of power system. The Generation Distributed(DG) access network will change the node voltage, branch power flow and line loss of the original system.Therefore, by combining the reactive power DG with the capacitor,optimal distribution of active power flow and reactive power flow of the distribution network is achieved. thereby reducing network loss, save energy and improve the reliability of power supply. To fully exploit the advantages of DG grid connected operation and decrease its negative influences,optimal allocation of DG and distribution network optimization problem are studied. The main work and research results are as follows:The author introduces and discusses several popular DG technique and grid structure of DG, and elaborates the calculating and processing method for distribution network containing distributed power flow. An optimization model of DG and capacitor supply, regarding the minimization of distribution network power loss as the objective function is established.Artificial fish swarm algorithm(AFSA) easy to fall into local optimum, reliability cannot be guaranteed. In order to get better optimization results, this paper derives the sensitivity of active power loss and reactive power loss sensitivity, and on this basis, defines the concept and formula of equivalent loss sensitivity. In this process, sensitivity method combined with artificial fish swarm algorithm is applied to optimize the model and the IEEE 33 standard node as an example of DG and capacitor to access to distribution network optimal location and capacity is simulated. The simulation results show the decline of distribution network loss of distribution network with DG optimal planning scheme and the improvement of the node voltage quality, which is conductive to DG accessing to network. Besides, the analysis and comparison among three methods combined the IEEE 33 standard system concludes that the sensitivity method combined with artificial fish swarm algorithm is better than the PSO and AF algorithm.The paper taking the distribution network of a certain area as an example, it is optimal simulation by AFSA based on sensitivity. The results show that this method is of great significance in guiding the planning and construction of distribution network, strengthening the economic efficiency of power network, saving energy consumption and so on.