Research And Implementation On The Three-phase APFC Based On DSP

With the development of power electronic technology development and social progress,the harmonic pollution problem has attracted more and more attention,solve the problem of harmonic pollution in power electronic equipment,improve the power factor,has important practical significance for the use of electric equipment rate and alleviate the problem of energy shortage in china.This thesis focuses on the research and implementation of three-phase active power factor,it uses the control strategy of space vector pulse width modulation technology and PI double closed-loop control,and studies the feasibility of digital threephase active power factor correction technology based on DSP.First of all,the thesis studies the characteristics of the main circuit topology.According to the demand analysis,it selectes the three-phase six switch topology as the main circuit of the system.Secondly,the mathematical model of the three-phase six switch main circuit is established,and its feedforward decoupling algorithm is studied.On this basis,this thesis designes a PI double closed loop control algorithm based on the current inner loop and outer voltage loop.Then,for the SVPWM algorithm,this thesis expounds principle and method in detail,and puts forward an improved method of SVPWM.Based on the SVPWM algorithm,establishes the MATLAB system simulation model of the three-phase APFC system,and analyzes the simulation results.Next,it designs a three-phase APFC prototype power of 10 KW.And then,each module of the system hardware design is introduced in detail,and gives each part of the software design process based on DSP main control chip TMS320F28335.The system hardware design mainly includes optocoupler isolation drive circuit,AC and DC signal sampling and conditioning circuit,zero crossing detection circuit,and the power supply module;the software part mainly introduces T1 interruption subroutine,ADC sampling subroutine,sine and cosine calculation,Zero crossing interrupt subroutine,and PI double loop control algorithm and SVPWM algorithm program.On this basis,the prototype is tested and the results prove the feasibility of the three-phase APFC system.