Study Of UPS System Based On Trans-Z-Source Inverter

Uninterruptable power supply (UPS) composed of energy storage device and inverter is a power supply protection device,which is used to stabilize output voltage and frequency. Because of the influence of traditional voltage source inverter, UPS has many shortcomings in practical applications. The proposed Trans-Z-Source inverter provides a new solution for UPS system design. It achieves boost function by shooting through state, which reduces the bus voltage requirements and increases the anti-interference ability. The new Trans-Z-Source inverter weakens the adverse effects of passive components on the inverter and solves the problems that existing in the traditional inverter. In this thesis, a new UPS system based on Trans-Z source inverter is studied. The main research contents are as follows:First of all,this thesis starts with the structure and working principle of UPS system. Aiming at the shortcoming of exist UPS system, such as low boost ability and low output harmonic, a new UPS system based on Trans-Z-Source inverter is proposed.The topological structure of the system is studied,the working principle is analyzed,and the components parameters of the new UPS system are deduced.Then, a three-lines shooting through control algorithm for single-phase Trans-Z-Source inverter is proposed, which is simplified by the regular sampling method.Double loop control scheme is adopted to ensure the stability of the output voltage.Finally, the system feasibility of UPS system based on Trans-Z-Source inverter is studied by Saber simulation software. The Trans-Z-Source inverter is built with DSP chip (TMS320F28335) to verify the theory. The result shows this new system is proved to be superior to the existing system, which has strong load capacity, low harmonic of output, longer battery life and stronger anti-interference ability. When the power grid is fault, high quality sine wave voltage can be provided to the users by this system,which optimized the user electricity.