14947

13453

كارشناسي ارشد

(قدرت(الكترونيك قدرت و ماشين هاي الكتريكي

اصفهان : دانشگاه صنعتي اصفهان

1398

يازده، 81ص. :مصور، جدول، نمودار

حميدرضا كارشناس

مسعود حاجيان، محمدصادق گلسرخي

1398/05/28

كتابنامه

برق

مهندسي برق و كامپيوتر

1398/05/28

2551800

Design and Implementation of a High current Synchronous Rectifier with Input AC Controller Ali Ebrahimpour mail ali ebrahimpour@ec iut ac ir June 13 2019 Department of Electrical and Computer Engineering Isfahan University of Technology Isfahan Iran Degree M Sc Language FarsiSupervisor Dr Hamidreza Karshenas karshen@cc iut ac irAbstractThis thesis concerns with improving the efficiency of high current low voltage rectifiers High current low voltage rectifiershave a widespread usage in the industry especially in the field of electroplating processes These rectifiers have certainchallenges and limitations The topology of a rectifier has direct impact on its performance The comparison of differenttopologies based on different criteria such as the conduction losses of semiconductor switches and the size of the transformerare addressed in this thesis Among various topologies the six phase topology with interphase transformer is adopted sinceit has the lowest conduction losses Most high current rectifiers must have the ability to control output voltage current The conventional method of controlling the power of these rectifiers is to use a controlled semiconductor switch such as athyristor at the load side of the transformer However in high current applications the higher voltage drop of controlledswitches leads to higher conduction losses and lower efficiency In this thesis a thyristor based AC voltage controller isemployed at the high voltage and low current side of the transformer resulting in lower conduction losses By changingthe firing angle of the thyristors the rectifier output power can be continuously controlled Another approach for reducingconduction losses in high current rectifiers is replacing the diodes with MOSFET switches Such rectifiers are sometimescalled synchronous rectifier as the switching command of power MOSFETs must be synchronous with the line voltage Replacing diode with a suitable MOSFET can significantly reduce conduction losses In this thesis various synchronousrectification methods are reviewed A driving method for is presented in which by inserting a proper dead time in MOSFETgating pattern the short circuit condition is avoided Simulations are carried out to verify the function of the proposedsynchronous rectifier and the driving method Simulation results show that the amount of synchronous rectifier losses issignificantly lower than that of a diode type In order to verify the simulation results a laboratory prototype of a six phasesynchronous rectifier with IPT with an AC voltage controller at the input are implemented It is observed that the practicalresults match the simulation results Key Words High power Rectifier High current Rectifier Controllable Rectifier Synchronous Rec tifier SR

حميدرضا كارشناس

مسعود حاجيان، محمدصادق گلسرخي