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Transformer less AC -DC CONVERTER

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STHOTA

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Hi, i am working on a circuit to build transformer less power supply to convert universal input to constant 240 V DC. Below i attached a design in proteus. It worked in the simulation, but not sure about the real time. Does the circuit seems reasonable and can I proceed with the hardware part?

Thank you
ac-dc final.JPG
 

What's your output current requirment? You're not going to get much with those HUGE 10K resistors.
 

It should give 2 amps at least. But do you think this circuit works?
 

TWO AMPS??!!! That means you've got to dissipate 40000 watts across those 10K resistors.
 

sorry , I was wrong. My total circuit is an AC-AC Converter. This is just the first part taking the universal input and regulating it to 240 V constant DC.
The other part of the circuit converts this fixed DC to 120 V AC, with 2 amps. My load is of 240 W LED driver. Below i attached the complete circuit. My simulation is showing some eroors for the full circuit.

Capture10.JPG
 

You still keep ignoring the fact that you are expecting to push 2 amps through a 10K resistor. I don't think using zeners the way you are showing is a very good idea.
 

A few things to get before proceeding with this project:
1. A couple good fire extinguishers
2. A first aid kit
3. Excellent home insurance
 

Okay. If I don't use 10K resistor, I'm afraid that the time constant for filtering ac to dc might get affected, which may in turn cause ripples in output DC.
Could you suggest any other value to the resistor? And, would there be any serious issue with zeners? They are the key components which are regulating the output to 239 VDC.
Upper one is a 200 V regulator and the down one is 39 V regulator.
 

You've got a source of 100V and a 39V zener. That means you need to drop 36 Volts (at 2 Amps) across your resistor. As I said, this is not a really good way to use zeners. Furthermore, if you've got a 100V Pk AC source, you're going to get 100V out of your FW rectifier, not 200 V.
 
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    STHOTA

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Okay. If I don't use 10K resistor, I'm afraid that the time constant for filtering ac to dc might get affected, which may in turn cause ripples in output DC.
Could you suggest any other value to the resistor? And, would there be any serious issue with zeners? They are the key components which are regulating the output to 239 VDC.
Upper one is a 200 V regulator and the down one is 39 V regulator.
We get transformerless AC-DC threads somewhat regularly, and the bottom line is that they're so inefficient that they end up being bigger and more expensive than a transformer, in addition to the safety hazards. And that's the case at power levels of just 10W. For 240W, it's a truly absurd approach.
 
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    STHOTA

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@mtwieg

Hi, Could you please explain, which of them would cause fire? I have got all the components and got ready to work on the hardware part, since the simulation worked perfectly well.
Please explain what changes I can make to the circuit to work under safe circumstances. Any help is appreciated.

Thank you
 

STHOTA, a quick refresher course on Ohms law might help you. No offense meant but you are asking for something completely impractical and extremely dangerous.

Re-run your simulation and place an 2A load (500W @ 240V) across the output and see what happens.

Brian.
 

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