The Research And Design Of Three-phase Inverter Paralleling Based On All-bridge

With the development of technology, modern appliances are becoming popularincreasingly, which makes the higher dependence of power energy for people. So it putforwards new requirement for the stability of power supply. Micro-grid makes that issuebecome a hot topic. The inverter which is developed is the equipment to convert powerenergy. But in the design of high-power, there are two different solutions. Different ofthe realizing high-power in single inverter, the solution paralleling several inverters getspopular. It improves the power supply reliability, but also lowers the cost.In this thesis, the parallel inverter is discussed. Analysis of different topology ofinverter, a new all-bridge structure is proposed. In this thesis, details including:(1)In this thesis, the background and significance of research are analyzed. Thepaper also analyzed the research status of parallel inverter in the domestic and overseas,and then the development tendency is concluded. It analyzed the principle of parallel,pointed that power sharing is the key. The key technology of parallel is introduced.(2)The paper analyzed the hardware topology of inverter, and then a new all-bridgein the three-phase inverter is proposed. The mathematical model in different coordinateframe is modeled. At last, the main circuit used in the thesis is given.(3)The paper analyzed the several popular control strategies in inverter control,merit and demerit are picked. The paper also analyzed the strategies of inverter parallel;then the PQ droop control is researched in detail. According the topology of this thesis,a strategy PI control and PQ droop control combined is proposed.(4)Modular design is applied，and according the system, parameters of everymodule is designed. According the strategy of this thesis, some software is introduced.(5)At last, the model in this thesis is modeled in Matlab, it used to check thefeasibility of the parameters and software design in the system. An experiment plot isconstructd in lab, and according the experiment analysis, the validity of system design ischecked further.