Research Of Passive Lossless Snubber Boost Converter Based On One Cycle Control

For AC/DC power supply, in order to meet demand of harmonic regulation andrealize low-cost, high-performance, the single-stage power factor correction(PFC)techniques have gained much attention these years, especially in low powerapplication. Single phase boost converter has been applied widely because of itsmerits, such as simple circuit, high efficiency and low cost, et al.In the PFC converter, conventional circuit control methods conclude Peak-currentcontrol mode, Average-current control mode, et al. Peak-current control mode needadd the slope compensator, and it is realized easily; Average-current control modeovercomes the shortages of Peak-current control mode, can control inductancecurrent accurately, is insensitive to the noise and it's following error is small.One-cycle control(OCC) mode PWM is adopted in this circuit. The instantaneouserror in every one cycle can be eliminated automatically and the error belonging tothe former cycle can't be brought to next cycle. The control method overcomes thedefects of traditional PWM control methods, and have the advantages of rapidresponse, easy to realization and simple control circuit.Passive lossless snubber circuit is used in the traditional boost converter. Thecircuit adds no auxiliary switch, no extra drive circuit, and the operation principle isalso no change. In the passive lossless snubber boost converter, dv/dt and di/dt isdecreased, diode reverse recovery current is suppressed, and the efficiency of thecircuit is improved.Principles of the power stage, control system and protection circuits were discussedin detail, and the design procedure together with methods for choosing parameterswere introduced at the same time. In this paper, A 1kW power experiment prototypehas been designed. As proved by experimental results, the advantages of OCC control method are verified and the passive lossless snubber boost converter was provedsatisfied.