Research On Reactive Power Optimization Considering Small Hydropower Connected To Distribution Network

With the country’s encouragement and support for new energy power generation,small hydropower,as a green energy source,has made a significant contribution to the realization of rural electrification and the improvement of farmers’ living standards.but the access of small hydropower will have a serious impact on the traditional distribution network and directly affect To the grid structure and operation mode of the distribution network,the rational distribution of reactive power is a prerequisite for solving the problem of small hydropower grid connection.Through reactive power optimization,reactive power can be reasonably allocated to ensure the safe and economical operation of the system.Therefore,it has important theoretical value and practical significance to study the reactive power optimization of small hydropower access to distribution network.This paper first briefly introduces the types of common grid-connected interfaces of small hydropower,selects the forward push-back substitution method as the power flow calculation method,and processes different types of nodes in the forward-backward generation method.Based on the ideal model of small hydropower grid connection,the IEEE 33 numerical example simulation verifies the influence of small hydropower grid-connected location and gridconnected capacity on distribution network voltage and network loss.Before the reactive power optimization,it is necessary to select the reactive power compensation point reasonably.In this paper,a voltage stability comprehensive index is used to reasonably determine the reactive power compensation point by synthesizing the singular value index and the local voltage index.At the same time,in order to improve the convergence efficiency of the algorithm,Reduce the amount of calculation,adopt an improved particle swarm algorithm,and comprehensively consider the influence of the characteristics of particles in the front,middle and late stages on the particle optimization ability.By modifying the internal parameters of the algorithm,the diversity of particles is effectively improved,and global and local search is enhanced.Optimize ability and speed up convergence.Considering the connection of small hydropower to the distribution network,a reactive power optimization model with minimum network loss and minimum voltage deviation as the objective function and node voltage exceeding the limit as the penalty function is established.The improved particle swarm algorithm is used to deal with the reactive power optimization problem.The calculation steps and program flow chart are given,and the reactive power configuration optimization method is simulated and verified by an IEEE 30 node example.The simulation results show that the proposed reactive power compensation point and optimization method are effective and reasonable.In addition,an example of IEEE 33 nodes is used to analyze the influence of different quantities of small hydropower on grid-connected reactive power optimization.The results show that when multiple small hydropower stations are connected to the grid,the IPSO algorithm can effectively solve the optimization problem of reactive power configuration in the distribution network with small hydropower.,the obtained optimization scheme is more reasonable and feasible.