Research On Control Scheme Of 3-Phase Voltage Source PWM Rectifier

In this paper, Mathematic models of the three-phase PWM converter under the balanced source voltage are separately set up in three-phase coordinate, α-β coordinate and d-q coordinate. And the connection among DC voltage,AC current, Source voltage and switching mode of converter is also included. Usually,the source voltage is unbalanced. In this situation, the traditional controlling method will bring large harmonics to the AC current and dc-link voltage. Hence improvements are needed. In this paper, Mathematic models of the three-phase PWM converter under the unbalanced source voltage are separately set up in three-phase coordinate and d-q coordinate. Meanwhile, two kinds of controlling scheme are given, which are the AC current controlling scheme that aims to make the AC current sinusoidal, and power controlling scheme that mainly aims to eliminate the harmonics of the dc_link voltage. Besides, the AC current controlling scheme is simulated by the Simulink of Matlab.On the basis of the theory analysis of three-phase PWM converter, a resolving strategy based on TMS320LF2407 for converter control system under the balanced system is proposed,including software designing and hardware designing. Meanwhile,the experiment platform has been made and the experiment on the current inner loop has been performed .The result prove that the control scheme can make the AC current sinusoidal..