Coupled indutor boost converter

[sabu31]

Hi

I wanted to know if there is any relation between the Gain factor of coupled inductor boost converter, Coupling coefficient(K), Loading and Magnetising inductance values.
ie

The gain of coupled inductor boost converter is given as Gv=1+N*D/(1-D) . N being turns ratio.(Here coupling factor is missing)

Now if assume N=4,D=0.5,and K=0.95. I am supposed to get a gain around 6. However when i simulate the circuit in PSIM, depending upon the load and also self inductance, the Gain factor varies drastically and it behaves almost like a simple boost converter.

Is there any upper limit to loading and self inductance in coupled inductor boost converter.?

 

[FvM]

The simple gain formula is only valid for ideal boost converters with k=1. I assume that you you can neglect a leakage inductance that's small compared to V*T/I, where T is the switching period.

 

[sabu31]

The simple gain formula is only valid for ideal boost converters with k=1. I assume that you you can neglect a leakage inductance that's small compared to V*T/I, where T is the switching period.

Hi FvM
Thanks for the reply. I wanted to know if boosting factor is depended on load and self inductance if k=0.9. .Assuming continuous conduction mode.

 

[FvM]

I presume, the "boosting factor" (Vout/Vin ratio) will depend on both in a real boost converter.