Research On Improved Trans-Quasi-Z-Source Inverter Based On SPWM/SVPWM

As an important research field in power electronic technology, the theoretical research of inverter has been very mature. With the development of modern industry and agriculture, the problem of energy shortage is becoming more and more serious.The power generation mode of fuel cell, solar energy, wind energy and so on is becoming more and more dominant, but the output of new energy power generation is unstable of the direct current or alternative current, and it is used directly only after being converted by the power electronic converter. In view of the above problems,this thesis introduces a single stage adjustable voltage inverter circuit.The improved Trans-quasi-Z-source inverter (Trans-QZSI) is a new type of inverter circuit. In the introduction part, the research significance of the improved Trans-QZSI is briefly introduced, and the development prospect of it is analyzed.Then, the working principle of the improved Trans-QZSI is analyzed, and the boosting factor is deduced. The boost characteristic of the modified Trans-QZSI is studied by comparing the quasi-Z-source and the traditional Z-source converter topology. The mathematic model of the Trans-QZSI is established by Laplace Transform, and its stability is determined by depicting the distribution of zero poles.In addition, the modulation principle of SPWM and SVPWM is introduced, and the shoot-through injection method is proposed to realize the boost function of the Trans-QZSI network. The influence of different shoot-through injection methods on the switching times and the switching losses of the inverter bridge are analyzed. The influence of different inductor and capacitor parameters on the response and fluctuation of the system is analyzed. Finally, the hardware experiment circuit is built on the basis of theoretical analysis and simulation verification. The boost characteristics of the improved Trans-QZSI are further validated.In this paper, only the operating principle and the boost characteristics of the improved Trans-QZSI are analyzed concretely, and the application of it does not involve, and this will be the focus of future research. Because of the superiority characteristics of the improved Trans-QZSI, it will has important applications in bidirectional power flow conversion circuits, high-power motor control and electric vehicles, which is also a very important future development direction of the improved trans-quasi-Z-source inverter.