Parallel Design And Research Of Single Phase Inverter Based On Droop Control

Inverter parallel technology is one of the important direction of the development of inverter technology.The technology is easy to expand and then improve the flexibility of the system,and easy to modular production,so that the entire system to reduce the volume.And the modules share the load current by common,greatly reducing the current stress of each device,improve the reliability of the system.The use of redundant power supply mode,when a single module failure through hot-swappable technology for single module maintenance,but also to ensure the stability of the entire system operation.In this paper,the control mode of single inverter is adopted in this paper,which is the control structure of double closed loop,which is the control structure of the output voltage outer ring and inductor current inner loop.The inverter operating state of the control structure is analyzed by simulation software.The final result shows that the control structure can realize the dynamic and static characteristics of the inverter.Secondly,the mathematical model of the parallel structure of the system is established,and the working principle of the parallel operation is analyzed.The conclusion is that the circulation is the main reason for the abnormal operation of the inverter parallel structure.The paper also analyzes and compares several commonly used parallel control methods,and finally designs the parallel control mode without interconnection.No connection between the parallel control system commonly used control method is droop control.Finally,the whole parallel structure uses three closed loop(current loop,voltage ring,sag ring)control mode.The circuit simulation model is built by MATLAB,and the analysis of the output result shows that the above control method has achieved a good current sharing effect,and the system can be well distributed and stable.Finally built a hardware circuit platform.