Research On Optimization Control Method Of SPWM Inverter Power Supply

With the continuous development of the times and the rapid development of science and technology,the field of power electronics technology has been applied more and more,and inverter power has received more and more attention.The application of advanced control technology can improve the stability and reliability of the output voltage of the PWM inverter system,and at the same time improve the dynamic stability of the system and other functions,and facilitate the optimization and upgrade of the system.PWM inverter system is developing towards digitalization,modularization,networking and intelligence.This thesis studies the key technologies of system control for digital PWM inverter system,and provides theoretical basis and implementation path for system design.PI control is the most widely used control method in practical engineering,and it is often used to control inverters.The traditional PI control algorithm is simple and has good robustness.However,for nonlinear and time-varying systems,the mathematical model of the system is difficult to establish,which causes some troubles for the traditional PI control.At the same time,the traditional PI control does not have the ability to adjust the kp and ki parameters online,and can not meet the tuning of the PI parameters when the error e and the variation of the deviation ec are changed,thus affecting the control performance.Intelligent control shows significant advantages in terms of improving system performance.Intelligent control includes fuzzy control and neural control.The advantage of these methods is that they do not depend on the precise mathematical model of the controlled object.In this thesis,a variety of control strategies are used for comparison.Through theoretical analysis and simulation comparison,the optimal control method is obtained.Firstly,the theoretical basis of inverter control technology is studied.The mathematical model of inverter power supply is established.The simulation model of single-phase SPWM inverter power supply is built by MATLAB software.Secondly,in view of the weak adaptability of inverter power supply and the poor dynamic and static performance,several inverter control strategies are proposed and made in-depth research.Through theoretical derivation and experimental simulation analysis,the advantages of integrated control strategy.Various control methods were compared to finally obtain a high-performance inverter power supply.In this thesis,a composite control based on RBF neural network self-tuning PI control is used to effectively improve the system’s inverter waveform quality and load adaptability.Through MATLAB simulation comparison,the simulation results and experimental results show that the total harmonic distortion value(THD)of the voltage output waveform is reduced,and the dynamic and static performance characteristics are optimized,indicating that the composite control method better satisfies the inverter.Power performance requirements.Finally,with TMS320F2812 as the control core,the hardware and software design of the system is carried out.The hardware design includes the main circuit of the inverter power supply,the power supply circuit,the drive circuit,the protection circuit and the filter circuit.The software design uses a modular program structure,including the main program,sub-program modules that generate SPWM waveforms.Through the DSP experiment,part of the debugging of the PI control system is completed.The experimental results show that the control method effectively improves the dynamic characteristics and outputs the ideal output voltage waveform,which proves the feasibility and effectiveness of the control method.