Research On Indirect Matrix Converter With Simple Commutation

Traditional AC-AC converters are often achieved through AC-DC-AC ways, in AC-DC-AC way, the capacitor is always used as intermediate storage devices to store energy. Therefore, a large capacitor should be contained in AC-DC-AC converter. Because the large capacitor has a relatively large size, which actually bring a lot of inconvenience to project. But the Matrix Converter(MC) combined by bi-directional switches hasn't intermediate storage, and MC has unity power factor in line side, high voltage transfor ratio , four-quadrant operation capability, so it has been becoming the focus of research.However, because of the complicated commutation problem in the traditional MC, it has been unable to apply in real project. In this paper, a novel type of matrix converter topology-Indirect Matrix Converter(IMC) is investigated, because of its specific structure, IMC has not only many advantages in MC, but also greatly simplifies the commutation problem, and applies the control strategy in the traditional three-phase inverter. IMC is made up by the rectifier and inverter. In this paper, Mathematic models of the rectifier and inverter under the balanced source voltage are separately set up in three-phase coordinate ,α-βcoordinate and d—q coordinate. Meanwhile, the relationship between grid voltage and output voltage are derived, a close loop control strategy is designed, and all the control strategies are simulated in PSIM.On the basis of the theoretical analysis of IMC, a resolving strategy based on TMS320LF2407A under balanced grid voltage is given, which includes hardware design and software design. The experiment platform is set up and debugged. The experiment results show that the control strategy proposed is able to achieve the goals: adjustable input power factor, zero current switch in main circuit, similar voltage transfor ratio compared with MC.