buck boost converter

Thread Starter

lapputappu

Joined Nov 25, 2009
16
Hiiiiii frnds i hav simulated a buck-boost converter in matlab simulink for 24v iinput to 160 v output . basically it is only using the topology of boost converter . i m attaching the design of boost concerter. and also the output after getting boosted .
The problem is the output contains too much ripples and harmonics and variation in output dc voltage .
so can anyone help me in this topic how to control this .....
 

SgtWookie

Joined Jul 17, 2007
22,201
You may have tried to attach a file that was too large, or not in an acceptable format.

The best way is to make a screen print using Ctrl+PrintScreen or Alt+PrintScreen, and paste the image into MS Paint. Save it as a .png file. .png format files are compact and are not "lossy" like .jpg files are.

Then use the "Go Advanced" button below the text box, and on the next screen click the "Manage Attachments" to select your image files to upload.
 

Thread Starter

lapputappu

Joined Nov 25, 2009
16
sorry frnd i hav reloaded the picture if u can den plz thanx in advance
here u can see that the output is across the parellel resisitance and capacitor which is about 340v . this can be minimised by reducing the inductor value
 

Attachments

SgtWookie

Joined Jul 17, 2007
22,201
Your values for R1 and C1 are not very realistic.
R1 is 50 Ohms. Increase it.
C1 is 2.5uF. Increase it.
It is not surprising that you have a huge amount of noise at your output.

You could add an inductor just after the diode to remove some of the noise.
 

Thread Starter

lapputappu

Joined Nov 25, 2009
16
as per u i increased the value of res nd cap
as r1 =8e3
c1=50e-5
and the obtained output is i m attaching .

After applying inductor nxt to the diode it reduces the output value and also produces interruption in output like slow increment in output
 

Attachments

SgtWookie

Joined Jul 17, 2007
22,201
Reduced the output voltage? All you had before was noise spikes! Now you have something that you can work with.

It looks like you did not allow as much time for the simulation to run as you did in the previous simulation that was all noise.

You did not post an image of your modified circuit.

The added inductor needs to be between the diode and the load.

It will help to reduce the noise more if there is another capacitor, perhaps 33uF, from the junction of the diode and new inductor, and ground.
 

Thread Starter

lapputappu

Joined Nov 25, 2009
16
thanx yaar but plz dis tym my system is out of order
so i will post the new circuit after sum days
 

Thread Starter

lapputappu

Joined Nov 25, 2009
16
now my simulation work is over .
this time i hav to implement this topology to make a hardware of dis system so can anybody plz help me to make hardware of this project
like the components used
circuit diagram implemented
 
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