How Max. Load Current change the desgin? in the boost converter

[ahmed osama]

Dear all

kindly if i want the max. output current 1 A or I want it 50 Adc what things will be changed in my desgin for the boost converter

i all read in the net relates the output voltage with the duty cycle no one speak about the output currnet

i have test many circuit , it works so fine when there is a load ( in range of 10 mA ) but if less than the output voltage keep growing and if more than than say 2 or 4A and output voltage decreased alot

thanks for any tips

 

[keith1200rs]

I would expect to see a diode in a boost converter. Have you built something or just simulated it? If you want a high output current you will also need a high input current so RL cannot be high. You need a feedback circuit to adjust the duty cycle depending on the output voltage. That would stop your output voltage from rising under light loads. There are other parameters to adjust - inductance and frequency for example.

Keith.

 

[FvM]

Nothing changes in a principle circuit like you presented. But there would be no RL in the ideal boost converter.

A real converter in contrast has series resistances respectively forward voltages of the switches, finite switching time, an inductor series resistance and core losses.