Research On Siangle-phase High-frequency Link Matrix Inverter Modulation Strategies And Control Methods

High frequency link inverter is the inverter which can solve problems in applicationof traditional inverter frequency transformer. It can not only achieve high efficiency, highpower density, low cost and has good dynamic characteristic, but also achieve theminiaturization of the system. With the developing of Power Electronics Technology, highfrequency link inverter has emerged its potential advantages, even in the field of newenergy technology. So it has a wide range of practical significance in studying highfrequency link inverter thoroughly.Firstly, the paper describes the advantages and disadvantages of traditional invertertechnology, after that, describes high frequency link inverter technology. In the study, wecan see the advantages and disadvantages of high frequency link inverter technology, itsclassifications and the development of domestic and foreign researches. This paperchooses single-phase voltage full-bridge high frequency link inverter as its object of study.Secondly, the paper tells about its modulation strategy——De-Re-couple，which isthe core of the study. This novel modulation strategy can achieve the modulation ofUnipolar and bipolar solutions De-Re-couple. The study also describes the square wavemodulation strategy. According to the characteristics of the square wave modulationstrategy with phase shift control combined, the paper analyzes the work modals ofmodulation strategy above, then does some corresponding computer simulations andexperiments.Thirdly, the paper analyzes the commutation process under the high frequency linkDe-Re-couple modulation strategy. Add the auxiliary switches at former level dead timeand use full “1” commutation strategy. For the commutation of former level dead time, thestudy analyzes four optimization strategy, and its core idea is change the former dead time.In order to improve the system’s commutation process, the study makes all secondary sidecommutations happen at dead time.Then, on the basis of high frequency link matrix inverter mathematical mode, thepaper applies pole placement to design modulator and study four closed-loop strategies. In order to improve the load capacity, the study combines one cycle control with outputvoltage and capacitor/inductor current. The paper makes a comparison of the control effectof various closed-loop strategies as well.At last, on the basis of the simulation, the paper uses digital control experiment, withDSP and CPLD, to confirm the feasibility and the effectiveness of modulation strategy andcontrol method. Through the analysis of waves, we can conclude a good dynamicperformance and the accuracy and feasibility of this method.