I made a dc boost converter that takes in 5 V DC and gives out from 8 to 30 V DC depending on the duty cycle . But as soon as I attach a load like an LED the volage drops to 4.3 volts instantly . What can cause such a problem I know that an LED can draw much current but I added an 1kOhm resistor to reduce the drop . Spoiler alert it didnt work , I still get 4.3 V even when I put it on the 30V mode . Any ideas ?

Schematic included at this link : http://tinyurl.com/y9jnnc29

PS : the simulation is not displaying the actual voltage values but every other value is as used in my circuit (inductor capacitor frequency) . The link is just here for the schematic diagram

MOD: Added the clip from the link.E

 

hi 79,
This is what your circuit shows in LTSpice simulation.
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So there is some kind of oscillation ? Can I get rid of it and keep the 11V DC stable ?

 

hi,
Try 10KHz instead of 1K, you could also increase the 1uF to say 10u
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It is 1mF not 1uF check my schematic please . Can you try it with this value ? Also Can you attach an LED between the resistor and ground ?

 

hi,
Is the 1mF label actually a 1000uF.??
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Yes it is never mind I fixed it now 10Khz gives 15V DC and 100kHz gives 60V DC , By the way my multimeter also measures 90V ac . Is this even posible?

 

hi,
So 10kHz drive fixes the problem, thats good.
The DVM will be measuring the average of the switching spikes.
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okay thanks for helping me with the project <3

 

The simulator circuit has no feedback and thus it has no way of responding to the increased load. Use a real world circuit with feedback and it will work correctly.