A Novel Decoupling Current And Sliding Mode Control Of The Three-phase Voltage-source PWM Rectifier

With the development of power electronic technology,the performance ofthree-phase voltage-source PWM rectifier has been widely used in variable flowdevice,such as Frequency Converter,UPS and Servodrives.Three phase voltage sourcePWM rectifier has significant advantage of sinusoidal input current and smallharmonic current.It basicly solves the harmonic pollution,and can also achieve unitypower factor,which is consistent with the “green energy”trend.Back-to-back PWMconverter consists of two identical three-phase voltage-type PWM converter,and itsstructure and operating characteristics become critical,so study the three-phasevoltage-type PWM Rectifier.Three-phase voltage source PWM rectifier iscomplicated,strong coupling,time-varying nonlinear system.The mathematical modelsof three-phase voltage source PWM rectifier in stationary and dq two-phasesynchronous rotating coordinate system are established,and then study its controlstrategy,MATLAB simulation.At last, experimental prototype and experimentalresults are given.Firstly,the mathematical models and principal of PWM rectifier is analyzed inthis paper,so prepared the way for further research on control strategy.Secondly,this paper uses the double closed loop control strategy,which iscomposed of inner current loop with decoupling current controller without exact valueof the boost inductance and outer voltage loop with sliding mode control,and makes adetailed theoretical analysis of these two control strategies.The control signals aremodulated by SVPWM technology.The simulation analysis demonstrate that theproposed method possessed good dynamic response and good robustness.Finally,according to a given technology parameter,give the design of hardwareand software of the system.The hardware circuit includes a signal regulatingcircuit,control circuit,protection circuit and so on.The software includesphase-locked,the control algorithm,SVPWM algorithm and so on. The paper alsodetailed analysis of phase-locked in the positive and negative phasesequence.Seriously debugged the sub-module of the hardware and software,andespecially analyzed the problem of system starting with a load at the process ofdebugging.Calibrated the ADC of TMS320F2812,and improved the absolute accuracyof the12-bit ADC.At the last,the system is debugged seriously,and experimentalresults demonstrate the validity of the proposed method and the feasibility of the control strategy.