| Converter technology has been used in industrial production field, more and more industries adopt rectifier technology to be the important process of production as the abvious development power electronics technology. At present, most inverter equipments have rectifier link. The rectifier is composed of power electronic devices. There has been great improvement of rectifier technology form previous uncontrolled diedode rectifier source to the controlled ones, but it still exists harmonic pollution. Therefore, this paper make the PWM current source rectifier such as its math model and control strategy be the research content to search for better result of controlling.The current source rectifier and the voltage source rectifier have symmetry in topology, so they have duality in control strategy. Otherwise, there is essential difference on PWM method. The PWM method of the former can be got by transferring the latter's. The control of rectifier's current is the most important and most difficult of research. This paper analyzes the two basic control methods of current control that indirect current control and direct current control. The indirect current control is simple and can be carried out easily, but it has bad dynamic stability and is sensitive about the change of load, so it can not be used in the field of high requirement on control precision. The direct current control adopts closed-loop current control, so it has high precision and strong robustness.To enhance the guide of theory research to practical application, this paper studies the rectifier's control under unbalanced power grid and gets the method of power regulation by calculating about the power system electromotive force. Furthermore, the control method which is different from balance state could be got. This paper does some simulations by Matlab/Simulink software bases on throretical analysis, the results show that the control strategies have good effects.
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