Abstract:
AT the morden days with the electrinic technology fast development , it is strict to power Supply in the many equipment’ using This paper analyzes the mechanism of electromagnetic disturbance in switching-mode power supply from the three aspects such as the component, the structure of circuit, the topology destruct of circuit according to the theory of electromagnetic and deduces the used of Classed D and power amplifiers of the switching mode power supply. And we analyze the reason that the two kinds of noise interfere to the electric network and discuss the harm of the disturbance to the electric network from the point of the theory of the switching mode power supply. After the discussion of the electronic and component cause of switching mode power supply we supply with some corresponding depressed methods such as the electrical isolation technology, grounding technology, filtering technology, the PCB technology, the method of placing line and so on. At last we discuss the soft switch technology and the frequency-modulation technology that are controversial now. In addition, the computation method about inducer, and capacitance, the design of department about the high frequency capacitance, the choice and setting principle about filters have been introduced detailed in the design of amplifiers filters and so on .
