Good Day,

I wish to make an ac to dc converter circuit.

Input: AC 230 Volts, 50 Hz
Output: DC 50 to 60 Volts
Power Dissipation: 500 Watts

Is it possible to make it without transformer. I have seen circuits online without transformers but not sure if it will be applicable for higher power handling of 500 Watts.

So what circuit and components should I be using for this.

Thanks.

 

Is it possible to make it without transformer.

Yes and no. It can be done but there will be on isolation from the power line. It is very dangerous.
That is way too much power for a "capacitor" dropping supply design.
AC230V, rectified and filtered gives you 325Vdc. That could be bucked down to 50 to 60V. No isolation.
They make transformers for a reason. They protect people.
What are you going to do with 50V at 10A?

 

Good Day,

I wish to make an ac to dc converter circuit.

Input: AC 230 Volts, 50 Hz
Output: DC 50 to 60 Volts
Power Dissipation: 500 Watts

Is it possible to make it without transformer. I have seen circuits online without transformers but not sure if it will be applicable for higher power handling of 500 Watts.

So what circuit and components should I be using for this.

Thanks.

You want 50V @ 10A. 10A is the important figure. Any resistive or capacitive dropper still takes 10A from the mains, In the resistive circuit, the remainder (180V) is lost as heat. 180V x 10A = 1800W. That's warm.
If you use capacitors. you would need 200uF and that would be almost as big as a 500W transformer and it still takes 10A from the mains.
The only method is with some type of high-frequency converter circuit and designing one above 100W is not trivial.

 

What are you going to do with 50V at 10A?

I want to pass a maximum 5 Ampere constant current through a ceramic Infrared Heater coil that I will add in series to an existing circuit.

I am using a 230 Volts AC to 36 Volts DC, 180 Watts Adapter, that powers a constant current buck converter which gives an constant current output of 5 Amperes at 18 Volts in the existing circuit to an inductive load.

But when I add the heating coil in series to the circuit, the current drops to 2 Amperes. The buck converter's voltage output is 30 Volts. That is the maximum constant current the buck converter can supply to this load at the Main DC input voltage of 36 Volts DC, though the buck converter can supply a max 10 Amps, it requires a higher DC mains voltage to do that.

Now I want to pass 5 A current through the circuit that includes the heating coil. That is why I thought of increasing the main input DC voltage to 50 Volts at a higher power rating of maximum 500 Watts.

AC to DC Adapters with more than 36 Volts DC output is not available in my place and also transformers of such voltage is not easily available and they are too expensive.

If There is any other way to do this please suggest.

 

I want to pass a maximum 5 Ampere constant current through a ceramic Infrared Heater coil that I will add in series to an existing circuit.

I am using a 230 Volts AC to 36 Volts DC, 180 Watts Adapter, that powers a constant current buck converter which gives an constant current output of 5 Amperes at 31 Volts in the existing circuit to an inductive load.

But when I add the heating coil in series to the circuit, the current drops to 2 Amperes. The buck converter's voltage output is 30 Volts. That is the maximum constant current the buck converter can supply to this load at the Main DC input voltage of 36 Volts DC, though the buck converter can supply a max 10 Amps, it requires a higher DC mains voltage to do that.

Now I want to pass 5 A current through the circuit that includes the heating coil. That is why I thought of increasing the main input DC voltage to 50 Volts at a higher power rating of maximum 500 Watts.

AC to DC Adapters with more than 36 Volts DC output is not available in my place and also transformers of such voltage is not easily available and they are too expensive.

If There is any other way to do this please suggest.

How about a diagram showing how you want to wire it.

 

How about a diagram showing how you want to wire it.

Yeah I know it is confusing...

I will make a diagram and post.

 

Ok I made two circuits. One without the heating element (Circuit 1) and the next which is the same circuit with heating element added in series with the load.

I cannot get the current above 2 Amperes, the buck converter reached its max value because the mains voltage is 36 Volts. In order to increase the current to 5 Amperes, I need to increase the main DC supply Voltage from 36 Volts DC to 50 Volts DC.


50 Volts to 60 Volts DC power source is not available, I wish to make one or find another method.

 

what is this inductive load? DC motor?
why would you power it and heater from same circuit? why not just get heater that operates on 230V?

 

36V @ 2A suggests you have an 18 ohm load when the electromagnet and heater are in series. Even if you supply it with 100 amps - the circuit will still draw only 2 amps. Ohms law.

 

what is this inductive load? DC motor?

No. Electromagnet.

 

if the inductive load draws 5A its DC resistance is 18V/5A=3.6 Ohm (first circuit). power draw is 18V*5A=90W

the second circuit says that combined resistance of heater and inductive load is 18 Ohm. so in that case heater is 13.4 Ohm.

you were looking for PSU of some 500W suggesting that heater is meant to draw up to some 400W. the bet solution is to power ist separately. if you insist in powering it from same source, then connect it in parallel with inductive load. in that case heater will draw some 22A and will need to have resistance of 0.82 Ohm.

to use same heater but in series with inductive load, 5A current, your DC supply would need to be 18V + 5A*13.4Ohm = 85V.
in this case heater will dissipate 335W

 

to use same heater but in series with inductive load, 5A current, your DC supply would need to be 18V + 5A*13.4Ohm = 85V.
in this case heater will dissipate 335W

I am just having a doubt on this. Because we are setting the constant current by adjusting the potentiometer on the buck converter, it reduces the voltage and supplies a higher current at that voltage.

Initially I used a 13.6 volts mains DC supply, the maximum current that I can set on the buck converter was 1.4 Amperes and the voltage was at 12 Volts.

Then I used a 36 Volts mains DC supply I can increase the current (by adjusting the potentiometer) to 2 Amperes. The buck converter can supply current of maximum 10 Ampere at maximum 30 Volts output (because the input is 36 Volts) above which it cannot give higher current output unless the main DC supply is increased to a higher level. If the buck converter input is 50 volts, it can supply 5 Amperes current on the same load (That is what I have my doubt on).

So I was calculating if I raise the input mains dc voltage to the buck converter, it could deliver a higher set constant current to the load. (Both the electromagnet and the heater coil)

 

I know this is not what you want but.... Think about Constant Current LED drivers.
Do you need CC or Constant Voltage? I don't see your need for CC.
Some of the LED drivers are Constant Voltage and some are Constant Current. Watch out! Some are adjustable and some are not.
There are some 100Watt 110 / 240V AC to DC constant current power supply for LED lighting.

 

I am just having a doubt on this.

you still have not told us anything, including what is the actual load is.
you mentioned it is inductive in nature but do you have part number, picture, specs, datasheet etc?

you mentioned to have ceramic Infrared Heater. fine but what are the specs? where is datasheet, nameplate info etc?

then you wanted to connect the two things in series - WHY? what is the reason to connect the two into same circuit? what are you trying to accomplish?

if the first one ("inductive load") can work with your buck converter, then that part is SOLVED! don't touch it... you only need to see how to power the heater.

if the two NEED to somehow relate to each other - explain THAT!

 

heaters are typically large loads. also they can be powered by either AC or DC. so simple dimmer circuit may do. by increasing value of R1 you can limit max power. no transformer needed.


and here is whole page dedicated to the same, including synchronous switching:
https://www.nutsvolts.com/magazine/article/triac_principles_and_circuits_part_1

 

then you wanted to connect the two things in series - WHY? what is the reason to connect the two into same circuit? what are you trying to accomplish?
.
.
.
if the two NEED to somehow relate to each other - explain THAT!

I dont have specs because I made the electromagnet myself.

The heater coil I got it online its rated for 230 Volt. Its a coil wound around a rod that is used in Infrared room heating. However, since it is rated for 230 Volts AC, I cut about 25 percent of it (the rod and the coil) and modified it for use at a lower DC voltage, it works fine, it heats up but I want to test it at different current settings.

I am trying to experiment on electromagnets and infrared heaters to learn and research about their healing potential. So trial and error comes to play.

Also I want to try something new because that could lead to something new. Anyways thats just my viewpoint.

 

There are some 100Watt 110 / 240V AC to DC constant current power supply for LED lighting.

I need constant current only. I test the magnetic patterns when current is constant at different set values of current.

Yeah those parts are available also those transformers are available in the US, but not in my place.

And getting those would be way too expensive.

I wanted to look for a simpler alternative which is possible for trying out with a 50 to 60 Volts DC power supply source that could power the buck converter.

 

i hear you but it would be easier if you would be more direct instead of tiptoing around the issues. for example you mention "US" and everyone knows where that is but you avoid stating what "my place" is. this prevents us from helping you.

MeanWell products are solid and low cost, for example LRS-450-48 would nicely do what you want. or try Amazon, Temu, AliExpress etc. they all ship everywhere.

 

I am trying to experiment on electromagnets and infrared heaters to learn and research about their healing potential. So trial and error comes to play.

Experimentation requires controlled variables. You'll get farther faster if the heater and magnet are completely independently controlled. This can be achieved if they are powered in parallel, just as if they were separately plugged into the wall, and so you will know the precise conditions being seen by each load. The supplied power may sag under load, unlike the wall plug, but you'll be able to monitor this. You could also gather data with the loads in series, but in that case you'll need to collect more data and you'll lose independent control.

 

i hear you but it would be easier if you would be more direct instead of tiptoing around the issues. for example you mention "US" and everyone knows where that is but you avoid stating what "my place" is. this prevents us from helping you.

I'm not tiptoing any technical issues I want to keep it simple so it does not create confusion.

I'm located in India. Yeah those ship everywhere actually its not the cost of the component itself but it is the shipping cost, customs and taxes that makes them expensive.

So I wanted to make them if possible with easily available components.