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I am trying to simulate the following case: A three-phase source in a Matlab is connected to a Vienna Rectifier which is supposed to supply power to a resistive load of 50KW. Output DC voltage to be 800V DC and the input voltage is 400V AC. Technically a Vienna rectifier after rectification also improves power factor, that is, reduces the input current distortion to be less than 5%. I have designed almost everything correctly still neither the Vienna rectifier is reducing the input current distortion nor it is boosting the output voltage at the DC link to be 800V. I cannot figure out what is wrong. I am trying to solve this problem for the past 2 weeks still no solution.

enter image description here

Please guide me with any resource or any advice or suggestion.

Thank you

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The problem seems to be with the drive to the MOSFETs. You have connected the PWM signals S1, S2 and S3 to the gates of the MOSFETs, but with respect to what? You can drive your MOSFETs if you apply a PWM signal to the gate with respect to the source, but not with respect to ground.

Take a look at the LTspice simulation below:

enter image description here

The PWM is applied to the gate with respect to the source.

In case of your circuit, you would need to add an isolated gate drive.

Here are the waveforms of the input voltage and current (just to show you that it works):

enter image description here

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  • \$\begingroup\$ I could not understand the point when you are saying applying PWM with respect to the source. If I am not wrong, you can see the PWM block is generating a PWM signal with respect to the input voltage and input current. Can I contact you for discussing this? \$\endgroup\$ – Arkadeep Deb Jun 3 at 10:41

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