翻译部分
英文原文
Modeling and Simulation of Three Phase High
Power Factor PWM Rectifier
Yu Fang*, Yong Xie * and Yan Xing*
*College of Information Engineering of Yangzhou University, Yangzhou, P.R.China *Aero-Power Sic-tech Center, Nanjing University of Aeronautics and astronautics Nanjing 210016,P.R.China
Abstract-Numerical simulation methodology based on high frequency mathematical model of high power factor PWM rectifier is proposed in this paper. And input to output transform function is deduced. With the help of input to output transform function, the design method of voltage regulator has been presented. The simulation for three-phase PWM rectifier is
implemented with Runge-kutta, thus comprehensive simulation can be achieved with M file in MATLAB. Finally, the simulation results and experimental results are given. The complete agreement with the results of simulation and experiment manifests that the proposed simulation method in this paper is effective. Of course, the design period of three-phase high power factor PWM rectifier can be shortened by virtue of proposed simulation methodology. Key words— power factor correction; SVPWM; Numerical simulation
I. INTRODUCTION
PWM rectifier is main technique applied in large unit power factor. Three phase PWM rectifier can be cataloged in voltage and current types, in which current type rectifier may employ many kinds of conventional PWM techniques, however, input line current is
discontinuous and output voltage ripple is much larger. While voltage type topology not only adopt many appropriate control strategies but also implements
bidirectional energy flow, and its main merit is that far dynamic response and simple configure. And smaller input filter can achieve lower EMI. Consequently, the voltage type PWM rectifier is usually served as power factor correction.
SVPWM is the best way to suppress harmonics [1-4],and used to adjust motor velocity. Especially it can attain low harmonics even in lower operating frequency. SVM can shape the input voltages of three phase bridge converter into rotating circular voltage vector. With the development of DSP, SVPWM have been easily
implemented so far. And another merit employing SVPWM in PWM inverter can achieve 15% more fundamental component among output voltage. Hence, if employed SVPWM technique in PWM rectifier, the use efficiency of DC voltage will be higher close to unit. As the result that the voltage stresses across switches is decreased.
The best way to implement SVPWM is digital control.Due to that DSP have been
commercialized, high performance digitalized SMPS come to true. However, it is hard to
program to implement controller in DSP, which result in longer development period. This case is remarkable in the design of three phase power factor correction; because in this case many control variables need to control and double closed loops must be accomplished. In face of this point, the numerical simulation methodology based on high frequency mathematical model of high power factor PWM rectifier is proposed in this paper. The simulation program contains the voltage regulator, current controller and the SVPWM, so we can call it comprehensive system simulation for PFC. The total simulation is implemented with M file in MATLAB, hence we only translate the M file into the DSP language to achieve digitalized three phase power factor correction. Consequently the compensation parameters can be optimized in simulation and the design period will be greatly shortened design cost cut. It is clear that the proposed simulation methodology is valuable for fast design of three-phase
PFC and may be used for reference to other digitalized SMPS design.
In this paper, the high frequency mathematical model is developed firstly, and then the control to output transformation function is deduced based on instantaneous power theory. It is nature that the voltage regulator is given and the PI regulator is testified to work here. In this way, we write these mathematic models into program in M file. And finally the simulation results and experimental results are given. The complete agreement with the results of simulation and experiment verify that the proposed simulation method in this paper is effective.
II. MODELING FOR PWM RECTIFIER The model is important way to analyze the operation basic, dynamic and stable state of PWM rectifier. The studied topology is shown in fig. 1. Assuming that: (1) idea switches
(2) ballanced input voltage source (3) without switching dead time
Fig. 1 Three-phase PWM VRC topology
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