Research On Middle-Power Stage High-Voltage Isolated Power Systems And Current-Source Input Voltage-Source Output Power Systems

This project focuses on middle-power level high-voltage isolation power systems and the relative second side power systems with current input source. In this paper, there will be some introductions about where to use this power system, many relative research works, and the goal of this time's research work.There exist four bottleneck problems in this project, they are: working of the Second-Side Power System(SPS) makes the Current-Bus unstable, this is the first bottleneck problem of the project; the increase of SPS power level makes the design of High-Voltage Isolation(20kV) Transformer(HVIT) hard, this is the second bottleneck problem of the project; working of Switching Second-Side Power Systems(SSPS) will bring "series-wound problem", which is a common problem of out-phased Current-Bus, and it makes the third bottleneck problem of the project; the increase of SSPS power level makes it's thermal design hard, this is the fourth bottleneck problem of the project. According to the problems above, this paper analyzes how to design current filter under the situation of Linear Second-Side Power System(LSPS) and SSPS; how to use Amorphous Cores in the design of HVIT and the advantages it brings; why "series-wound problem" happens and the relationship with SSPS switching frequency; how to improve power losses of LSPS and how to use PCB for the thermal design of SSPS.Further more, this paper also introduces two kinds of small-signal models of PFC, working roles of current source, how to use double-loop feedback loop in current bus and how to use optocoupler in the design of assistant power systems.In the last, by solving the problems mentioned above and adopting of other amendatory methods, this paper finished the research work of this project. The power level of whole system reaches 1200W and the power level of each SPS reaches 100W. At the end of this project, first-Side of this power system using two stage CL filter combining with LSPS and First-Side of this power system using single stage CL filter combining with SSPS have been finished.