# About With a transformer, 220Vac to 24VDC Design / 50A Output Current

#### doompeac3

Joined Apr 25, 2019
7
Hello, I need to design a circuit which is about battery separator. There are two sides of the projects. A circuit will be supplied with battery or 220Vac. Our Battery voltage is 24Vdc and it can provide approximately 50A continous current. The other side of the circuit is 220Vac. I have to decrease the 220Vac to 24Vac (battery voltage) and I have to rectify that circuit. According to system request, I must switch the supply voltage from 220V to battery or from battery to 220V. However, I need to provide 50A current from transformer side. Because of this situation, I need to use bridge rectifier which is capable of providing 50A continous current or mucher than that value.

Or, I can design a SMPS to provide this current and to supply the circuit with that. Yet, I know that the design process will be very difficult if I choose this design process.

Do you have any suggestions for me? I really need your suggestions for the design process about project. Thanks in advance.

#### drc_567

Joined Dec 29, 2008
1,088
... Just to clarify the problem, you are not necessarily trying to recharge a 24 volt battery. The objective is to devise a DC supply circuit that will provide 24 VDC and 50 amps DC.
... If that is correct, then a transformer with a winding ratio of 220:18 VAC and a volt*amp rating of 2 KVA (or larger) should be sufficient to handle that specification.
... If recharging a 24 V battery is required, then something different is necessary.
... suggest using 5 KVA or 10 KVA transformer for extra capacity . Overheating should be avoided.
... The 18 VAC transformer secondary output will be converted to 24 VDC after it is rectified and sees filter capacitors ... can't provide a numerical estimate of the capacitor magnitude that would be required by a 50 amp load.

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#### doompeac3

Joined Apr 25, 2019
7
If your question is whether you can avoid needing a 50A rectifier, the answer is yes.

https://en.wikipedia.org/wiki/Active_rectification

Bob
Yes. Thank you for your answering. The situation is to avoid needing 50A rectifier. Choosing of capacitors is another problem for me. Because I need the capacitor bank which is capable of providing 50A continous current. My area is restricted by previous design.