Research On Improved Droop Control Strategy Of Microgrid Inverter

The microgrid is a controllable independent system composed of distributed power supply,control device,energy storage device and load.It has the advantages of low pollution,high efficiency and flexible control to ensure users to use more reliable and high-quality electric energy.Whether the microgrid can operate stably and whether it can provide high-quality electric energy is the control strategy of its inverter.Among the control strategies of microgrid inverters in application,the most widely used control strategies are constant power control,constant voltage constant frequency control and droop control.The droop control applied to the microgrid inverter is the most widely used control method in the distributed control strategy.It attempts to simulate the regulation characteristics of the synchronous generator in the traditional power grid,so that the distributed power generation unit itself has voltage and frequency adjustment capability,and can The load power changes are shared according to its drooping characteristics.The conventional droop control will cause the power coupling problem caused by the control error caused by the difference of the control line impedance.This paper proposes an improved droop control strategy for power decoupling for the drawbacks of conventional droop control.In this paper,the background and research significance of the topic are systematically expounded.Then the definition of microgrid and its development status at home and abroad are briefly summarized.The development prospects and research hotspots are systematically analyzed.This paper then establishes the mathematical model of the microgrid inverter under the static coordinate system and the dq rotating coordinate system,and studies the control strategy of the microgrid inverter,focusing on the application of the droop control with more applications,and establishing different lines.Mathematical model of droop control under the model.Aiming at the problem of power coupling caused by the control error caused by the difference of control line impedance in the traditional droop control,this paper proposes an improved droop control strategy for power decoupling,and establishes a mathematical model to improve the droop control,which improves the droop control.The controller was designed and a small signal model for improved droop control of the microgrid inverter application was established.At the end of this paper,the proposed improved droop control strategy is simulated.Based on the mathematical model of the improved droop control,this paper builds a simulation model for improving the droop control of the microgrid inverter on the Matlab/Simulink simulation platform.The simulation results show that the improved droop control method proposed in this paper can solve the problems of conventional droop control,improve the dynamic response speed of droop control,and improve the stability of the system.