Hello everyone. I am designing a boost converter. It has 12 A (avg) current and 200-600 V input voltage range. Output voltage range beetween 600-850 V. I couldn't make a decision about the inductor. I would like to use standard E70 core. I wanted to use 400uH as inductance value however I exceed the current value that the inductor can handle at the discontinuous conduction mode. Inductor can only handle maximum 21 A . I thought increasing inductance would be good but I am not sure that would be alright with that standard core. Calculations say it is possible however I can have more resistive losses. Can anyone give me an advice about that?

 

Your choices are to increase the switching frequency or increase the inductance.

If increased number of turns gives too much resistance loss then you will need to go with a larger core that has room for larger gauge wire.

 

What if I use the boost in the discontinuous conduction mode and have higher peak for the current. Do you think that E70 can handle peak current such as 26 A?

 

The amount of peak current an inductor can tolerate depends upon the saturation characteristics of the core material and the number of turns. You have to calculate the peak magnetic flux and see if it exceeds the core rating.