Research And Design Of Inverter Based On LC Filter Circuit

With the increasing depletion of fossil energies,the demand for energy markets at home and abroad continues to be tight,and the world is increasingly dependent on new energy sources.Looking for new energy sources to replace traditional energy sources has become the focus of the world’s attention.Photovoltaic power generation,as a new energy generation mode,has attracted worldwide attention for its advantages of green environmental protection,sustainable development and short construction cycle.As a conversion device that can make energy flow in both directions,the inverter is the key core of photovoltaic power generation.It plays an important role in improving power quality,improving power supply stability and conversion efficiency.Therefore,it is of great significance to study and design the inverter system.This thesis takes the single-phase full-bridge inverter system of LC filter circuit as the research object,completes the overall scheme design,circuit design and PCB design of the inverter system,and performs function debugging and performance testing of the system.The main contents of the thesis are summarized as follows:(1)According to the technical index requirements of the inverter system,the topological structure of the main power unit is selected,and the overall scheme design of the inverter system is completed.The selection of main components such as power switch tube,data acquisition chip and driver chip is determined.The hardware design of the system is completed.On this basis,the overall design of the circuit is completed and the power consumption of the circuit is calculated.(2)The specific hardware circuit and PCB of the inverter system are designed.According to the functional division of the circuit,the detailed circuit design of the main power unit,drive unit,data acquisition module and power supply module is mainly completed.Focus on completing the parameter design of the LC filter and the design of the drive circuit.According to strategies to suppress reflection and crosstalk,the device layout and wiring design of the main power board and the driver board have been completed respectively.(3)The software design and model simulation of the inverter system are completed.Using the idea of modularization,the main program of the system,SDFM sampling subroutine,discrete switch sequence control subroutine and PWM timing interrupt subroutine are designed.Using a new type of discrete switch sequence control algorithm,the main power unit is modeled and simulated with MATLAB,and the results are analyzed.Compared with the existing control algorithm,the steady-state accuracy and dynamic performance of the system can be accurately analyzed by this method.(4)On the basis of completing the hardware circuit design and software design of the inverter system,the experimental platform is built.Then the main power board and the drive board are debugged separately.Functional tests are carried out on each unit to verify the validity of the hardware circuit.The technical index of inverter system is realized.