Dsp-based Three-phase Voltage Rectifier

The conventional rectifiers produce most harmonic problems in power system. While 3-phase PWM voltage source rectifiers (VSR) can overcome the previous shortcomings , it is getting more widely used. It can provide constant DC voltage and acquire line power feedback capability. In this paper, 3-phase rectifier is the study point ,including its principle, topology, mathematical moedel, and the completion of its control methods on software and hardware. In order to study VSR, its mathematical model is essential to set up. Thus, its models are established respectively in ABC coordinate,αβcoordinate and dq coordinate. This paper focuses on 2 control methods: SVPWM and DPC.SVPWM is the key point of the study, whose simulation model is set up with the final simulation results. Based on the hardware platform of DSP2407, program is developed according to its control methods. The experiment proves the reliability of this method.The advantage of DPC (direct power control) lies in that its structure is simple, dynamic response is quick,and it has the ability to resist disturbance. This paper introduces the theory of instantaneous power, the principle of DPC and the selection method of voltage vector. The common switch table is not ideal, with bad control result of the reactive power. So a new method of switch table is presented, in order to improve the performance. This new method of switch table is based on the theory of adding a lagging comparing part. The simulation and the experiment prove the utility and reliability of the new method.And at last, these 2 control methods are compared, bringing respectively the shortcomings and specialities.As the necessary part of the experiment, the paper also presents the design of inductance and capacitance in VSR, the main function about DSP2407, and the using of intelligent power module (IPM),and the parameters of sampling part.