| High-frequency PWM rectifier can be controlled of a good performance in AC / DC conversion. It can provide sine,low harmonic input current,controllable power factor, achievable of the two-way flow of energy. It can be called as a reversible PWM rectifier. Since the PWM rectifier can exchange energy not only from the grid to the DC side, which performs as the rectifier. It can also exchange energy from the DC side to the grid, which works in the inverter state. PWM rectifier is therefore the four-quadrant converter operation system.According to the single-phase voltage-type PWM rectifier's switches'state at different moments of the operating time, we established a single-phase voltage-type PWM rectifier basic mathematical model. Application of the average state space method to establish rectifier's the average state space model, Rectifier will be a linear model. We designed the controller based on this model.The single-phase voltage-type PWM rectifier uses dual-loop controller. Voltage loop PI controller is to achieve stable DC output voltage. Voltage loop controller's output will be the rectifier's input current command. Current loop controller's purpose is to control the rectifier's input current to be in the same phase with the grid voltage. Not only the output DC voltage of the rectifier is stable, but also the rectifier has unity power factor and low THD. Controllable power factor and load energy feedback to grid are a prerequisite for grid phase detection. In this paper, a simple digital phase-locked loop is analyzed. The circuit and experimental results of the digital phase-locked loop are given.In the PWM rectifier's controller technology, there are mainly two types of control program. The first is the indirect current control. Indirect current control is represented by the phase and amplitude control. Indirect current control has the advantage of simple controller. There is no need to carry out the design of current loop feedback control. The problem of this controller is that the input side of the current response is too slow, and it is sensitive to the parameters of the system. Thus it is often suited to less demanding on the dynamic response applications. The other control scheme is the direct current control. It mainly includes current control with fixed switch frequency and hysteresis current control. This type of direct current control can perform high-quality current response. But the control structure and algorithm are more complicated to the indirect current control. For these reasons the direct current control is the dominated control scheme. In this paper, the three control schemes are analyzed and designed. For these control schemes, S-function which uses the C language program for the simulations are proposed based on MATLAB2006a/SIMULINK. In this paper, DSP2812 and FPGA-based control system for single-phase voltage-type PWM rectifier is completed. The single-phase voltage-type PWM rectifier control programs are verified in simulation and experiment.Based on the electric locomotive traction applications the single-phase voltage-type PWM rectifier is developed. In the high-power applications, switching devices'frequency is limited. In this paper, the back section of the low switching frequency of this condition has done a simulation and experimental. Compared to works in the high-frequency, the rectifier works under the special experimental phenomena. In this paper, the particular phenomenon of this experiment is analyzed, and gives inspiring solutions. |
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