Study And Design On Three-phase Voltage Source Pwm Rectifier

Three-phase voltage source PWM rectifier has significant advantages of sinusoidal input current and unit power factor, DC voltage constant and rapid adjustment control, good dynamic performance, and bi-direction power flow, ect, which meets"green power conversion"trend, thus gains extensive application and research.Three-phase voltage source PWM rectifier is a strong coupling, time-varying nonlinear system, control is more complicated. This paper focuses on the engineering design and implementation of three-phase voltage source PWM rectifier control system, including the research of control methods, the implementation of space vector, the design of hardware and software, and the development of prototype.Firstly, the typical topologies and principal of PWM rectifier is analyzed in this paper. The mathematical models of three-phase voltage source PWM rectifier in ABC three-phase stationary and dq two-phase synchronous rotating coordinate system are established. A hybrid nonlinear control method based on dq mathematical model for three-phase voltage source PWM rectifier is presented completely. Dual closed loop control structure on the controller has been designed to realize decoupling control of three-phase voltage source PWM rectifier's active and reactive power. It uses sliding variable structure control as the voltage outer loop, to make full use of its strong robustness for the changes of system parameters and load disturbance to control DC output voltage and generate current index; and uses variable structure control based on input-output linearization as the current inner loop, to make full use of its rapid response, high tracking precision and strong anti-disturbance ability, according to current index of the voltage outer loop to realize unity power factor and sinusoidal current control. Meanwhile, combined with the theory of AC motor vector control, this paper gives the voltage space vector control of three-phase voltage source PWM rectifier and analyzes its realization method in details. By building Matlab simulation model, the feasibility of the proposed three-phase voltage PWM rectifier control method is verified by simulation results.Secondly, the paper gives main technical parameters of three-phase voltage PWM rectifier , and the system hardware and software is designed. Hardware, this paper introduces the main circuit LC design method, the power switch selection, and the drive protection circuit design, etc. Software, it uses the TI company's TM320F2812 as controller, and presents the detailed software design flow, and the digital implementation of control method.Finally, the prototype of three-phase voltage PWM rectifier is constructed and debugged, experimental results verify the validity and superiority of its control method and engineering design.