Research On Control Method Of Three-p Hase PWM Rectifier Based On The Novel Hysetsis SVPWM

PWM control technology as one of the best control methods has the advantages ofmaking the system operate at unit power factor, inhibiting harmonics effectively andachieving bi-directional energy flow, which the other traditional control method can notreached. Because of its controllable power factor, bi-directional energy flow and lowharmonic pollution characteristics, three-phase voltage source PWM rectifier has been paidextensive attention by researchers. However, there are still some shortages in three-phasePWM rectifier control, such as unstable switch frequency result in high harmonic distortionthat existed in traditional hysteresis control strategy and control lag caused by massivecalculation in space vector control strategy, so in this paper, in order to solving these problems,a novel control method is proposed.Based on plenty of domestic and foreign literatures, the developments of PWMtechnology and modern power electronic have been introduced in this paper at first. Themathematical model of the three-phase PWM rectifier has been analyzed and the workingprinciple of rectifier has been explained simultaneously. After introducing the control methodscommonly used of the three-phase PWM converter in detail, such as hysteresis control andspace vector control and its improvement method, a novel hysteresis space vector controlmethod which combines the respective advantages of hysteresis control with space vectorcontrol is proposed. This method is based on the αβ coordinate system, which can avoidmutually independent and lack of coordination that happened in three-phase ABC coordinate,by using multilevel hysteresis comparator optimize the relationship between control accuracyand switching frequency. This method also has more characteristics, such as lower switchingfrequency, unsensetivity to load changes, reducing THD and control simply. After operating inthe Simulink, the feasibility and efficiency of this method primarily is validated.In the end, this paper establish a whole experimental prototype, hardware and softwareare designed, specific hardware models are showed. Based on lots of experiment verify thismethod is superior to the traditional method.