High Efficiency AC/DC Switching Power Supply Design

Due to the continuous development of economy,people life level unceasing enhancement,all electrical equipment and appliances to work without power supply,power supply,because the switching power supply has high reliability,low energy consumption,light weight,small volume and easy to use,and a series of advantages,so in the military,aerospace,post and telecommunications,medical equipment,instrument and meter,and household electrical appliances and other fields has been widely applied.The brief analysis of this article without the source power factor and the advantages and disadvantages of active power factor,illustrates the necessity and the importance of power factor,and the basic principle of active power factor correction are analyzed in detail and the control method.Through the comparison of the main circuit topology and control method,choose the boost converter circuit as the main circuit topology,based on average current control UC2854BDW controller,calculated the control chip peripheral circuit,and the input filter design,electromagnetic interference,the output inductor,components of the parameters,such as reducing the application of power electronic devices harmonic pollution to power network,improve the input power factor and power efficiency,accord with the requirement of green development.Dc transform part with MOSFET as power switching tube,a booster of the whole bridge switch converter,using pulse width modulation technology,the control signal is produced by the integrated controller UC2825ADW,from real-time sampling output voltage feedback signal,to control the change of the voltage.Between the control circuit and main circuit through the transformer isolation,and over-current and over-voltage protection circuit design,has realized the reliable switching power supply,light weight,small volume,high efficiency and safety,etc.Design and manufacture a new AC/DC2500W prototype,after the prototype test,input voltage and input current in phase,and the current waveform is close to sine wave,the output voltage stability in 28 v,output efficiency is as high as 90%above,achieve the expected effect,realized the high efficiency of switch power supply,power factor correction circuit is adopted in the prototype,significantly improve the power factor of the circuit,reached the design requirements,at the same time,the total harmonic distortion factor of circuit control in a certain range,reduce the pollution to the grid.Through prototype testing and simulation,the experimental results meet the design requirements,but also proved the correctness of the design and accuracy.