Research On Voltage Control Strategy Of Multi-Energy Microgrid Access To Distribution Network

Due to global energy issues and environmental pollution issues the integration of multienergy microgrids has become a new trend in grid planning.The connection of multi-energy microgrids improves the flexibility and economy of the distribution network,makes the traditional distribution system more controllable,and improves the impact of load fluctuations on the voltage quality of the grid.However,the access of uncontrollable micropower in the microgrid makes the operation and control of the distribution system more complicated.Improper control will cause problems such as unqualified power quality on the demand side.In this paper,the voltage stability of multi-source microgrid access to the distribution network is divided into three aspects: multi-energy microgrid modeling,microgrid voltage distribution,voltage control strategy considering voltage constraints and network losses.Conduct in-depth research on voltage control and stability of the distribution network.The main work and results of this article are as follows:(1)Multi-energy microgrid modeling.This paper analyzes the working principle of DG represented by wind power and photovoltaic power generation,as well as the working principle of micro gas turbine and composite energy storage system,and establishes a mathematical model for voltage stability analysis.(2)Analysis of the influence of micro-grid access on the distribution network reactive voltage.In order to clarify the influence of the location and capacity of the microgrid on the voltage distribution,a theoretical analysis of the voltage distribution principle of the microgrid access to the distribution network is made using the load triangle distribution model.Analyze the influence of micro-grid distribution network on voltage distribution and stability from two aspects of MG access location and capacity,adopt the most optimal address based on voltage sensitivity index,and the optimal fixed volume based on the smallest active network loss The method explained the rationality of the analysis and was simulated and verified in Matlab/Simulink based on the IEEE14 node distribution system.(3)Reactive voltage control strategy for multi-energy microgrid access to distribution network.In order to better control the voltage stability of the microgrid,a dual reactive voltage control method with microgrid is proposed,which combines centralized control with different local control.Realize coordinated control of active and reactive power of controllable load.And the centralized control is combined with different local control methods to meet different control requirements.Finally,take the improved IEEE33 node and the improved EU16 node as examples to verify the effectiveness and rationality of the control strategy.