Research On Electromagnetic Transient General Decoupling And Simulation Method Of Electric Energy Router

As the "double-high" power system becoming the main form of power grid development,Electric Energy Router(EER)based on new power electronics technology has become one of the core devices of flexible AC/DC power distribution network.The EER can adjust the energy flow,realize the voltage level change,and coordinate and optimize the "source-grid-load-storage" of the power system in a fast,accurate,flexible and efficient way,thus ensuring the safe,economic and stable operation of the distribution network.The electromagnetic transient simulation is an important technical tool for the study of controllable strategies of power router characteristics.When detailed model simulation is used,due to its complex topology,high switching frequency,large number of power modules and devices,so the simulation efficiency is extremely low,and it is difficult to meet the practical needs of engineering applications.Facing the challenges of large-scale systems,high-dimensional matrices,and low-efficiency operations in simulation,there is an urgent need for an efficient general power router modeling method.In view of the current research status and electromagnetic transient simulation problems of power routers,the following research work is carried out in this paper for the general electromagnetic transient decoupling model and simulation method of power routers.1.Semi-implicit delay decoupling model of electric energy routerThe semi-implicit delay decoupling method can realize fine-grained decoupling and parallel simulation between link level and module.Based on this principle,this paper derives the semi-implicit decoupling model,port equivalence transformation model and power coupling topology model for H-bridge modules based on matrix splitting and delay techniques.After that,these decoupling models are integrated and spliced to obtain a general semi-implicit delay decoupling model for power routers.This model has the advantages of high generality,constant conductance matrix,and parallel speedup.The model is proved to have good stability,and the parallel computation timing and computation flow are designed.2.Decoupling model of power router unitWith the optimization of transformer magnetic devices,power electronic topologies and power semiconductor components,power routers have gradually become more practical in distribution networks,and many new types have been derived.In this paper,we introduce each topology type and the development status of power routers in the history of development.An electromagnetic transient decoupling model for different power router topologies is constructed and the computational speed and accuracy of the decoupling model are verified.The results show that the proposed decoupling model for power routers is not only general,but also achieves the speedup of serial computation while satisfying high accuracy.3.Decoupling parallel computing for large scale electric power router systemsThe Central Processing Unit(CPU)based parallel simulation method for flexible AC/DC distribution networks is studied.The general decoupling model proposed in this paper has high parallelism in principle,so the parallel simulation method and implementation process of fine-grained decoupled sub-circuit model are designed by using a multi-threaded CPU as the simulation environment and C++as the programming language to take advantage of the parallel computing technology of CPU.The efficiency of the parallel simulation scheme proposed in this paper is verified by selecting the flexible AC/DC distribution network topology.Analysis of the experimental test results shows that the model in this paper shows more significant speed-up effect than the serial calculation in parallel calculation under the premise of ensuring stability and accuracy,and it increases with the number of modules.