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The Simulation Study of Direct-Current Control Technology for Three-Phase Voltage Type Rectifier

The diode uncontrolled rectifier or the phase controlled rectifier is widely used in conventional rectifier link, thus the conventional rectifier link on the grid inject a large number of harmonics and reactive power, and they cause a severe grid “pollution”. This paper starts from the basic principles of the PWM rectifier, then the paper discusses the topological classification of three-phase PWM rectifier in detail. Based on topological structure, the paper builds the mathematical model of three-phase stationary coordinate system and two-phase rotating coordinate system. Based on space voltage vector, the paper studies PWM control method in-depth and simulates in Matlab/Simulink. The correctness of the theoretical study of three-phase voltage source PWM rectifier system is verified by the simulation results.