# PSpice boost converter output voltage problem

Discussion in 'Power Electronics' started by orcuns91, Aug 31, 2020.

1. ### orcuns91

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Aug 31, 2020
Hi everybody,
I'm trying to evalute the performance of SiC mosfet in boost converter. After importing the model of the device to pspice, I simulated it in a basic boost converter circuit. However, the output voltage of the circuit is higher than the theoretically expected 800 volts. My values are f=50k Hz Duty=0,75 Vin=200 L=150uH C=10uF. Could you tell where the wrong is by looking at the pictures I uploaded? Thanks in advance

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2. ### WHONOES

1,190
322
May 20, 2017
Tried it on my simulator and am getting about 740V. What sim are you using?

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3. ### orcuns91

3
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Aug 31, 2020
Thanks for your answer. I'm using OrCAD capture pspice simulation. In my simulation , the input current is higher than expected. How can I limit the input current? Also, could there be a problem in driving the mosfet?
The model of mosfet is https://www.rohm.com/products/sic-power-devices/sic-mosfet/sct3022klhr-product.

4. ### WHONOES

1,190
322
May 20, 2017
I use a simulator called SIMETRIX, have done for many years in my professional life and now in retirement. I think it is the best of the bunch.
One thing to remember when doing this sort of simulation is that the inductor will need some dc resistance. I generally include it as a small value resistor either before or after the inductor.
Another is that when using a voltage multiplying circuit such as yours, the input current will increase by the same ratio as the voltage multiplication factor plus a bit to account for losses. Thus if the input is 200V and the output is 800V which is a factor of X4 then with a load of 160R resulting in a current of 5A at the output then, the input current will be 20A.
You don't get something for nothing.

See attachments for my schematic and performance graphs

#### Attached Files:

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• ###### SCT3022 GRAPH.pdf
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5. ### orcuns91

3
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Aug 31, 2020
Thank you very much for your advice. I will simulate again after reviewing the files.