Design And Study Of Three-phase Voltage Source PWM Rectifier Based On DSP

Three-phase voltage type PWM rectifier compared to the conventional diode-controlled rectifier or thyristor phase-controlled rectifier has the advantages of the sine of the net measured current, unity power factor, energy flow in both directions, the system can run in four quadrant. Has become a power electronic converter and the grid interface, get more and more extensive research and application.This article introduces common topology of PWM rectifier and analyzes its principle, based on which the detailed working states of rectification and inversion for three-phase PWM rectifier are analyzed, and qualitative analysis of switching processes for different working states are also given. In order to determine a control strategy, it establishes mathematic model for three-phase voltage PWM rectifier in different coordinate systems.Establishes power model for the three-phase PWM rectifier based on instantaneous power theory, directly control its active power and reactive power. Direct power control employs dual-loop structure, and replaces the traditional inner current loop and DC bus outer voltage loop with inner power loop. It also replaces the traditional power control switching table by introducing of SVPWM algorithm, to solve the problem that higher AD sampling frequency is needed if switching frequency is not fixed. Then, for the sake of simulation, on Matlab/Simlink2010b, it establishes direct power control model of three-phase PWM rectifier, to justify that it has higher power factor, lower current THD, high efficiency and so on.This article designs prototyping system of three-phase PWM rectifier. It employs PS21867as the core part of power drive, TMS320F2812as the core part of controlling, to respectively construct the power unit circuit and controlling unit circuit for the prototyping controlling system. The general methods for designing Fuse, Selection of power devices, AC side inductance and DC side capacitance are also simultaneously given.Finally, it writes the controlling program for the three-phase PWM rectifier based on modular programming ideas. It separately designs the main program, the voltage zero-crossing detection subprogram, T1interrupt service routine, AD interrupt service routine, Keyboard and display routines, Build an experimental system debugging experiment on the experimental system of three-phase PWM rectifier, Given the experimental waveforms,by means of experiments, justifying control algorithm developed in this article, as well as engineering feasibility and superiority of three-phase PWM rectifier.