Research On Power Flow Algorithm Of Weak Loop Distribution Network With Distributed Power Supply

In recent years,the power system has gradually replaced the original power generation,transformation,transmission,distribution and consumption systems by largescale and centralized power supply systems.At the same time,environmental and resource problems have become more and more serious.To solve the above problems,a distributed power supply is widely access to distribution network,but when a distributed power grid,the radiation of simple network structure changes,a new node type,and also appeared a few weak ring in distribution network,which makes the active power distribution network power flow calculation,the traditional power flow calculation method cannot achieve satisfactory effect,Therefore,it is of great significance to study the improved power flow calculation method in the power flow calculation of weak loop main distribution network.Firstly,the power generation principle of common distributed power supply is analyzed and a mathematical model is established,which is simulated into four node types:PQ,PV,PI and PQ(V).For the initial value of PV node,reactive power allocation principle is adopted,and reactive power modification value is calculated on this basis,and the method is verified to be closer to the actual initial value of reactive power.It can effectively reduce the number of iterations in power flow calculation.Secondly,aiming at the problem that the traditional power flow calculation method can not calculate the modern distribution network,in the radial network,an improved backward generation method based on node stratification is proposed.In IEEE33 classic calculation example,the proposed method has strong applicability and convergence,and the calculation time is shorter.The influence of different types of distributed power supply and access to multiple distributed power supply on node voltage and network loss is analyzed.In the weak-ring network,the weak-ring network is firstly de-looped,and the model of de-looped network is established.The compensation current of the de-looped port is calculated and replaced into the system for power flow calculation by the established Devinen circuit.When the number of weak-ring networks increases,the loss of distribution network decreases,the voltage of nodes increases,and the voltage offset decreases.Finally,the static voltage characteristic model of load is established.In the IEEE33 node distribution system example and the actual distribution network in northern Anhui,the power flow calculation of the distribution system network containing both distributed power supply and weak loop network is carried out.According to the results of power flow calculation,the influence of different types of distributed power supply,different permeability and different access point locations on the voltage and network loss of distribution network nodes under different static voltage characteristics of loads is analyzed,and the permeability value of the distribution network with the minimum network loss is obtained.Figure [40] Table [17] Reference [74]...