Special DC/DC Converter Research And Application

Based on the principle of DC/DC converter technology, the characteristics of the public bus voltage of the pumping frequency group control system, and the demands for power rating and the number of loops from the whole system, a kind of switching power supply special for this occasion is researched and designed.Firstly, the research is launched on the topological structure of the Flyback converter, and power supply suitable for this occasion is designed using this kind of structure. It determines the compensation network parameters to achieve optimal by analyzing the transfer function of each loop, considering the accurate model of the peak current control and light-coupler small signal, and using MATLAB, thus getting fast dynamic response. The design of the Flyback converter and the selection process of the RCD ground-clamp circuit parameters is given, as well as it gives the specific measures to reduce of the peripheral circuits electromagnetic interference from the power in the PCB layout.Secondly, a kind of power supply, which has a mixed cascade topological structure and can realize multi-way voltage output is designed, whose basic thought is to convert the voltage after stabling it. The former level converter uses Buck TL circuit, which has many advantages comparing to the ordinary Buck circuit, for example, it can reduce filtering inductances and the capacitors'volume, and has small ripple voltage, etc. In order to achieve a better result, state space model is built and MATLAB is used to determine the outer circuit compensation network parameters. The later level circuit uses a forward converter structure, which adopts an active ground-clamp strategy, thus saving the third forward-type transformer windings. The whole system start circuit takes advantage of the DC circuit control relay contacts with the start circuit of the switching power supply, which is simple and feasible.Finally, it study the isolated power supply for the special high-voltage system——based on public high-frequency alternating current bus program. The main circuit constants current source generating circuit which is a dual-Buck circuit, through the full-bridge inverter and the CL filter network, the high-frequency sinusoidal current, signal is got. The high-frequency current bus loops through the high magnetic ring through the secondary side rectification and filter the output voltage can be got, and through double-loop control strategy for the output voltage stability, in order to prevent high-voltage it designs the over-voltage protection circuit.This study develops the switching power for the public bus voltage of the pumping frequency group control system and carries out a large number of experiments. Experimental results show that the prototype is running stable & reliable and the test targets meet the requirements to prove the correctness and feasibility of the formula.