Design Of 200W LED Driver With Style Of Active-Clamp Forward Switching Power Supply

LED lighting becomes more and more popular in factory , infrastructure and homes as a new lighting for its characters such as the energy conservation, the invironment protection,the security , the rich color , the longevity , the small volume ,bears the twinkle , the high reliability ,the regulation is convenient. LED will perform better with proper driver,so the dissertation is about how to design a driver matches LED lighting.In the paper we firstly introduce the advantages of LED lighting and application status, as well as the broad prospects of LED. Secondly, we introduce the basic principles of LED's light-emitting , analysis the relations during voltage, current and LED light-emitting efficient and.By analyzing several styles of LED driver,proposed forward-type active-clamp converter circuit structure.Switching power supply have become the mainstream form of power supply industry for its own advantages,for the power becomes smaller, lighter, higher efficiency and better performance.We carry out a detailed calculation for the key parameters in the main cirduit. A specific design is completed for the transformer.The specific parameters of the transformer was amended depend on the practical applications in the special circumstances. Then we pointed out the key factors and solutions that affect the performance of the transformer in the manufacturing process .We choose NCP1280 as the central control device in the power driver. In the dissertation we tested and analisised the circuit based on the NCP1280. The power is designed with over current protection and over voltage protection circuit based on feedback loops.More attention is focused on the common problems in the middle-power switching mode power supply(SMPS). We make more measures to deal with the EMC problems and finally the SMPS meets EMC standards GB17743; We make measures to solute the heat dissipation problem;And take the soft switching technology as zero-current switch and zero-voltage switch to resolve the serious problem of switch dissipation .We optimized the structure of the circuit system according to the observed waveform and revised data , parameter selection is instructive.Finally the paper describes the sample of the power with output of 200W36V, analysis the test results and made recommendations for improvement. Give the prospect of its application and practical significance. For a long time observation, it is proved to be a stable power supply.