Related Research Of The Three-Phase Voltage Source PWM Rectifier

With the rapid development of modern society,the power in modern industry plays anincreasingly important role,but in the national production and life are closely related withthe power electronic converter devices,such as the frequency converters,high-frequencyswitching power supplies,power inverters and other various converters,the use of thedevice will give our power grid to bring a lot of unfavorable factors,such as a large amountof reactive power and harmonic,low power factor,or even cause severe electromagneticpollution,resulting in the use of other equipments are not normal in same network.With thedevelopment of power electronic and PWM technology,the rectifier has the characteristicsof high power factor,harmonic minor,DC output voltage stability and has operate in thefour-quadrant,etc.It becomes a green power conversion device.Therefore,the main researchsubject of this paper is the three-phase voltage source PWM rectifier.Firstly,base on the analysis of the three-phase rectifier system main circuit topologicalstructure and the four quadrant operation of working principle,the main circuit componentparameters are designed and in the three different coordinate system the mathematicalmodel of three-phase PWM rectifier is derived;elaborated on the three-phase PWM rectifiercontrol method,and the controllers are designed,further introduce the voltage space vectorcontrol.Secondly,the unbalanced grid conditions of three-phase PWM rectifier operation areanalyzed,on the basis of derivation of instantaneous power,have studied the inhibition ofnegative-sequence current of the AC voltage outer loop double current inner loop controlstrategy,improved the operating performance of the rectifier in unbalanced grid conditions.Finally, through the power balance and unbalance condition different unbalanced gridsystem model simulation and experiment under the equilibrium condition, the results verifythe validity of the theory.