CLASS D GROUNDED AMPLFIIER

[navnee4]

HI ALL

Can the use the attached toplogy for grounded amplifiers

thanks in advance

Naveen Kumar P

[baga]

Yes, because the transformer isolates the output stage from the mains. You can put that ground anywhere in the output stage. BUT , if you don-t isolate the input from inverter or the driver, you must not ground the input from the inverter or any device connected to the input.

[navnee4]

Originally Posted by baga

Yes, because the transformer isolates the output stage from the mains. You can put that ground anywhere in the output stage. BUT , if you don-t isolate the input from inverter or the driver, you must not ground the input from the inverter or any device connected to the input.

hi
thanks for ur reply
i am experimenting now of power level 40kva

regards
naveen

[Pafi]

Interesting. Somebody who wants to build such a huge device asks such a basic question?

(And with a conventional transformer, instead of SMPS?)

BTW: why is that stage called "unipolar"?

[navnee4]

Originally Posted by Pafi

Interesting. Somebody who wants to build such a huge device asks such a basic question?

(And with a conventional transformer, instead of SMPS?)

BTW: why is that stage called "unipolar"?

' i have already build class D for BTL upto 70KVA
now my requirement of class D is grounded shaker i thought i can use the same by isolating
since my input is 415V,3Ph (india) i have to step down my voltage for the selection of MOSFETs @ that particular current rating.
UNIPOLAR is a type of PWM technique used for BTL type Class D PAs

[prem]

this circuit at times gives shock

[baga]

Pafi is right, if you work with that voltage and power, you must know that things, otherwise you can take an electrical shock or that thing can explode in your face.. TAKE CARE.
What mosfets are you using for that power ?

[fredos]

I use this topology for over 10 years in my D-Amp HVI series. Work well and stable, but you need to use post filter feedback. No need for the 2 cap and resistor that go to V-. Just make sure that you add voltage divider from PSU to front stage to keep each leg of bridge at 1/2 Vcc.

[navnee4]

Originally Posted by fredos

I use this topology for over 10 years in my D-Amp HVI series. Work well and stable, but you need to use post filter feedback. No need for the 2 cap and resistor that go to V-. Just make sure that you add voltage divider from PSU to front stage to keep each leg of bridge at 1/2 Vcc.

THANKS fredos for your suggestion
i appreciate your point of voltage divider technique which is impressive and i will implement it.
I am taking feedback before filter but it is not effective for compensating dead time so i have added cap and resistor to V-. My PWM is uniplor PWM

please suggest for dead time compensation and feddback technique

[navnee4]

Originally Posted by baga

Pafi is right, if you work with that voltage and power, you must know that things, otherwise you can take an electrical shock or that thing can explode in your face.. TAKE CARE.
What mosfets are you using for that power ?

HI BAGA

I am using 48Amps 500V MOSFETs which are paralleled for required power