Research On Operation Optimization Of AC/DC Distribution Network With Distributed Power Source

With the vigorous economic development,distributed power sources gradually occupy an important position in modern power systems.Not only brings economic benefits to the distribution network,but also improves environmental problems.At the same time,due to the large number of power electronic components and the increasing non-linear load,the traditional AC distribution network structure can no longer meet the development needs of contemporary society.The construction of AC and DC distribution networks to enable the distribution network to operate economically,steadily and reliably is already the trend of economic and social development.This paper first studies the power flow calculation method of the AC and DC distribution network,and uses the alternating iteration method to calculate the power flow of the distribution network.The alternating iteration method is to obtain the power flow of the entire network by continuously alternating the AC subnet and the DC subnet.Distribution,therefore,the power flow calculation of the AC distribution network and the DC distribution network are studied separately.The AC distribution network uses the forward pushback method,the DC distribution network uses the Newton-Raphson method for power flow calculation,and the types and processing methods of distributed power supply nodes connected to the AC and DC distribution network are studied.Taking the improved IEEE33 node network system as an example,the AC and DC distribution network is simulated.Secondly,the influence mechanism of distributed power supply on the network loss and voltage level of the distribution network is studied,and the simulation analysis is carried out with an improved IEEE33 node network system.The analysis results show that the active and reactive power in the distribution network affect the distribution network Operating state,so when optimizing the distribution network,active and reactive power coordination and optimization should be adopted.Then,the calculation principles and processes of the particle swarm optimization algorithm and the cuckoo search algorithm are introduced.The advantages and disadvantages of the two algorithms are analyzed.Based on this,an improved cuckoo search algorithm based on the particle swarm algorithm is proposed and passed the test The function verifies the effectiveness and optimization performance of the improved algorithm.Finally,the output characteristics of the photovoltaic power supply are introduced,and the reactive power provided by the PV,the active power of the energy storage device and the reactive power provided by the parallel capacitor bank are used as the control variables,and the coordinated optimization model called active and reactive power is established,and the improved The IEEE33 node system is used as an example to optimize the active and reactive power coordination of the AC and DC distribution network.The results of the example show that compared with the unilateral reactive power optimization,the active-reactive coordinated optimization can provide AC and DC distribution network Better operating conditions have improved the economics of distribution network operations.