The Research And Design Of High Frequency Switching Power

In all sorts of power electronic equipment, Switching Power Supply as its power supply units plays an important role. A complete Switching Power Supply System is mainly by the input circuit, switching converters, transformers, output circuit, control circuit composed of several parts, the AC input into DC power required for electronic equipment. At present the Switching Power Supply to high frequency, integration, intelligence, and other direction development, it's played an important role on the power electronic equipment performance improvement.With the development of computer technology, the modeling and simulation of Switching Power Supply have assistant effects on power design and study; it can not only shorten the researching and development cycle but also reduce the design cost. The modeling and simulation research of power supply have become the essential part for Switching Power Supply researching and developing, and as simulation software improved, the simulation of Switching Power Supply is simpler, the part and function of Switching Power Supply can be simulation also more and more.This paper studies the System Power Supply in Sophisticated System, analysis the present situation and development of High-frequency Switching Power Supply domestically and overseas, analysis the common DC-DC converter's topologist's structures and elements'characteristics, point out each converter's advantages and disadvantages, and the principles of choosing the right topology for the different Switching Power Supply, study the main part of the Switching Power Supply and the design method, select a reasonable design and set design on this basis. The design process includes the following sections:the main circuit and control circuit design, design of the various parts of the circuit diagram and analysis, the Pulse Width Modulation COMS circuit SG3525's structure, working principles, driving circuits, High-frequency Transformer's design and calculated the parameters in the circuit, which focuses on the various calculated parameters of High-frequency Transformer, select the appropriate device on this basis. The paper has found the main circuit's and control circuit's models by using the simulation software, simulated and investigated these models' performances under the case of different parameter's changing, the calculating parameters and the device was verified, then pick out the right parameters according to the practical performances. The whole system design was perfected, the over-all model has been formed by the assistant models mentioned above, and the feasibility of the power supply is demonstrated.Due to the design of Switch Power Supply in strong electromagnetic interference environment, vulnerable to outside interference, in order to enhance the dependability and reduce Electromagnetic Interference (EMI), switching power supply must have protection circuit with complete performance and the ways and means that can reduce EMI, this paper concludes with the measures to solve EMI and experimental methods.