Objective: Design an isolated DC-to-DC flyback converter Flyback Design A 100W notebook power adaptor that can be used in North America and Europe accepts a universal input of 100-250Vrms AC at 50/60Hz and provides a fixed DC output of 20V at up to 5A. The notebook power adaptor is low cost, inefficient, and operates with poor power factor. Its power architecture consists of a full-wave rectifier providing a rectified average DC voltage ranging from 90-225VDC followed by an isolated flyback converter. Your task is to design a flyback converter for the notebook power adaptor to meet the design criteria that follow. You may assume that all components are ideal and the flyback converter operates at a switching frequency of 100kHz. (1) your design should accept an input voltage range of 90-225Vdc and provide an output of 20Vpc at up to 5A full load. (2) your design should operate with a continuous magnetizing inductor current down to half load. (3) the peak-to-peak output voltage ripple should not exceed 2% of the average output voltage. (4) the flyback transformer should have a minimum number of turns on the primary and secondary in order to minimize conduction loss (e.g. instead of selecting a turns ratio of 16:4, you should select 4:1; note that these numbers are arbitrary and not necessarily what you should actually have). Your task is to select a transformer turns ratio, magnetizing inductance and output capacitance to meet the required specifications and determine the worst case voltage stress for the diode and switch used in your flyback design. In addition, you must check the diode current stress (peak and average) and MOSFET current stress (peak and RMS). Finally, you should select an appropriate MOSFET and diode to meet your specifications. To do so, you will need to search for appropriate devices from semiconductor manufacturers. Possible manufacturers include, Vishay, International Rectifier, Fairchild Semiconductor, and NXP. You will need to adjust your duty cycle to meet the design requirements. You may use the space that follows to complete your design (neatly). Ns:Np= Lm= MOSFET Vsw pk= Isw_pk Isw_rms MOSFET manufacturer & part # Diode Vd_pk= Id pk= Id avg Diode manufacturer & part # (2) Comment on which input/load combination(s) determine your design constraints and stresses. Objective: Design an isolated DC-to-DC flyback converter Flyback Design A 100W notebook power adaptor that can be used in North America and Europe accepts a universal input of 100-250Vrms AC at 50/60Hz and provides a fixed DC output of 20V at up to 5A. The notebook power adaptor is low cost, inefficient, and operates with poor power factor. Its power architecture consists of a full-wave rectifier providing a rectified average DC voltage ranging from 90-225VDC followed by an isolated flyback converter. Your task is to design a flyback converter for the notebook power adaptor to meet the design criteria that follow. You may assume that all components are ideal and the flyback converter operates at a switching frequency of 100kHz. (1) your design should accept an input voltage range of 90-225Vdc and provide an output of 20Vpc at up to 5A full load. (2) your design should operate with a continuous magnetizing inductor current down to half load. (3) the peak-to-peak output voltage ripple should not exceed 2% of the average output voltage. (4) the flyback transformer should have a minimum number of turns on the primary and secondary in order to minimize conduction loss (e.g. instead of selecting a turns ratio of 16:4, you should select 4:1; note that these numbers are arbitrary and not necessarily what you should actually have). Your task is to select a transformer turns ratio, magnetizing inductance and output capacitance to meet the required specifications and determine the worst case voltage stress for the diode and switch used in your flyback design. In addition, you must check the diode current stress (peak and average) and MOSFET current stress (peak and RMS). Finally, you should select an appropriate MOSFET and diode to meet your specifications. To do so, you will need to search for appropriate devices from semiconductor manufacturers. Possible manufacturers include, Vishay, International Rectifier, Fairchild Semiconductor, and NXP. You will need to adjust your duty cycle to meet the design requirements. You may use the space that follows to complete your design (neatly). Ns:Np= Lm= MOSFET Vsw pk= Isw_pk Isw_rms MOSFET manufacturer & part # Diode Vd_pk= Id pk= Id avg Diode manufacturer & part # (2) Comment on which input/load combination(s) determine your design constraints and stresses
