Three Phase Imbalance Management Of Distribution Network In Wuan Grid Power

In recent years,the economy of Wuan is booming,the living standard of the people is increasing and the power load is increasing.Therefore,higher demand for the power supply quality and operation reliability of the distribution network in this area is also raised.According to the measured data of distribution network load in Wuan in 2017,there are about 2891 public distribution transformers on line monitoring in the city,of which there are more than 380 public distribution transformers with three phase unbalanced problems,accounting for 12.99 percent of the total number of common distribution transformers.Therefore,this issue is based on solving the three phase imbalance in Wuan radio distribution area,and formulates reasonable and effective management measures to apply it to the distribution radio area of Wuan power grid so as to improve the local power quality problems.Firstly,this paper briefly describes the current situation of three phase imbalance in the distribution network area of Wuan power grid,and points out the main factors that affect the three-phase imbalance in the area.Secondly,taking the load phase sequence of the commutative node as the optimization variable,the objective function is to minimize the power loss,minimize the three-phase current balance,minimize the three-phase voltage balance,minimize the average voltage drop of the distribution network node voltage,minimize the neutral current of the main transformer in the distribution network and minimize the loss of the distribution network.Based on the thought of weighted aggregation normalization,the multi-objective function is transformed into a single objective function based on the thought of weighted aggregation normalization,and the quantum particle swarm optimization algorithm is used to solve the problem.In addition,a distribution station in Wuan power grid is taken as the measured system,and the phase change scheme obtained by the set of load phase sequence equilibrium optimization model is used for artificial commutation operation.The actual results show that the distribution network commutation scheme based on the method proposed in this paper can reduce the total number of power switching lines as far as possible.It can effectively reduce system losses and reduce the overall imbalance of threephase current,and improve the three phase voltage asymmetry of each node.Therefore,the research in this paper has certain guiding significance and practical value for the safe and economic operation of Wuan distribution network.Finally,this paper gives some suggestions on how to avoid the three phase unbalance of the radio station from the planning design,the construction acceptance to the operation and maintenance of the Wuan power grid distribution area.