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

With the wide application and development of power electronics technology, the powersupply system adds a lot of non-linear loads, causing the grid voltage, current distortion,resulting in power pollution. Conventional diode and thyristor rectifier system as powerelectronic devices to interface with the grid, harmonic pollution is particularly serious. Inrecent years, the technique of PWM rectifier with high power factor, low harmonic pollution,energy can flow in both directions, small capacity storage link, a constant DC voltage controladvantages, can effectively reduce the harmonic pollution, which has been extensiveresearched and engineering applications.By reading a lot of references and information, we are familiar with the mathematicalmodel of PWM rectifier in a variety of coordinate systems and associated control strategies.On this basis, this paper takes a three-phase voltage-type PWM rectifiers for the study, atheoretical study of its voltage loop controller, the current loop controllers, and space vectorpulse width modulation (SVPWM) control algorithm. Then, we use the sliding mode variablestructure control, PI control methods and parameters SVPWM modulation technique forthree-phase voltage-type PWM rectifier control system design and simulation analysis.Finally, we use TI’s DSP--TMS320F2812chip as the control core, on the basis of thedomestic and foreign research results, the voltage and current double closed-loop controlsystem.The main contents include: the principles and theoretical analysis, describes the topologyof three-phase voltage-type PWM rectifier, the mathematical model and coordinatetransformation, including the mathematical model of three-phase and two-phase stationarycoordinate system rotating coordinate system, common SVPWM control strategy as well aspulse width modulation technology and its implementation. In system modeling andsimulation, we established a double-loop three-phase voltage-type PWM rectifier controlsystem Matlab simulation model, in which the voltage loop using variable structure controlstrategy, current loop PI regulator traditional and feedforward decoupling control strategy,given the system simulation waveforms and conclusions. Hardware design, includingcalculation and select the main circuit inductance and capacitance parameters, the selectionand design of its power device driver protection circuit, zero-crossing detection circuit designand sampling design and various protection circuits. In the system software, we are given asystem based on TMS320F2812controller chip main software implementation process, theinterrupt routine processes and algorithms routine processes for each program for a more detailed description. Finally, we set up the experiment platform based on TMS320F2812experimental prototype, and debug a three-phase voltage-type PWM rectifier control systems,test the main output waveform under different loads. Through these experiments we getconsistent with the theoretical analysis of the experimental results, which also confirmed thereliability and feasibility of the system design.