Research And Design Of Three-phase VIENNA Rectifier

With the rapid development of power electronic technology,many kinds of power electronic devices are widely used in all kinds of flied,which has brought great convenience to human life and production.However,it lead to the increase of reactive power loss,voltage drift,current harmonic pollution and other problems,which are becoming more and more important.Therefore,the study of high power factor,low current harmonic PWM rectifier device has become more significant.The three-level rectifier have many advantages,such as the active switch with low voltage stress,the output currents with low harmonic currents and the voltage with low rate(dv/dt)in the ac side,which are suitable for medium and high power applications.Compared with traditional three level rectifier,the three-phase three-level VIENNA rectifier has advantages of less power switch devices and no direct connection of output voltage,so do not need to set up drive dead zone.Therefore,it has won more and more attention by majority of scholars at home and abroad.This paper will focus on the research and design of the three-phase VIENNA rectifier.This paper firstly introduce the evolution of rectifier topology and the topology of the Vienna rectifier.Then,it analyze the single-phase and three phase working principles of the circuit topology of the VIENNA rectifier,and the characteristics of the three-level obtained.Lastly,the mathematical model of VIENNA rectifier in three-phase stationary coordinate system,two-phase static coordinate and synchronous rotating coordinates established by using the switching function.Based on the mathematical model of VIENNA rectifier,this paper give a design method of PI controller parameters,which is using system open loop cut-off frequency and phase margin to get controller parameters.The method establishes the relationship between the frequency domain performance and the time domain performance of the system.At the same time,it can intuitively see the influence of each parameter on the performance of the system.However,PI controller has many shortcomings such as fixed and sensitive controller parameters,and poor anti-interference ability.Therefore,a model predictive control method with neutral point potential balance is proposed.By establishing the prediction model of the system,the article get the predictive control algorithm of the voltage loop and the current.In the meantime,the midpoint potential predictive control is added to the control algorithm to achieve the balance of neutral point potential.Finally,through simulation and comparative analysis,it is verified that model predictive control is superior to PI control in terms of dynamic performance and steady-state performance.For the space vector modulation of the VIENNA rectifier,the article introduce the SVPWM with the normal hexagon partition mode.It is different from the SVPWM with the positive triangle partition mode,which have no trigonometric function calculation and more suitable for computer algorithms.Then,the article analyze the midpoint potential balance problem by space vector,and propose a middle point potential balance method suitable for space vector modulation.Finally,this paper introduce the design of the hardware circuit and software program of the three-phase VIENNA rectifier prototype,and building the prototype.The accuracy and feasibility of the control strategy is verified by the experimental results.