220AC to 220DC converter

[nadre25]

Hi, can anyone give me a schematic or suggest a way of how to convert 220AC to 220DC. We will use the 220DC as a supply for a motor in our project.

Is it possible not to use a transformer?

Help is very much appreciated!

 

[betwixt]

Probably. What power/current is needed to operate your motor and how critical is the voltage stability?

Brian.

 

[nadre25]

for the motor, the current needs 2A. With respect to voltage stability... well.. i have to get back at you..

 

[betwixt]

i can't help you with a schematic but my approach would be a bridge rectifier to convert the AC to DC, followed by a phase controlled SCR to regulate the voltage. That would happily supply 2A and should be good for a brief burst at much higher current as the motor starts up. Depending on the motor characteristics, you may need to use a capacitor across the DC to reduce voltage ripple.

Brian.

 

[mishra12]

a bridge rectifier will convert from ac to dc and what type of motor you are using that is not clear

 

[DeepOne]

may be do like that

however for usual engine single bridge rectifier will be enough.

 

[kak111]

For general dc-motor you can use only diode bridge
without filter condensator.
For control use normal triac controller ( light dimmer or motor controller )

Look picture.....................

View attachment 220ac_dc.pdf

 

[nadre25]

Thanks for the tip, um what do you mean by "Phase Controlled SCR" do you have a schematic for that? Thanks!

---------- Post added at 14:06 ---------- Previous post was at 13:56 ----------

Hi Guys, i tried a circuit. the problem is it reaches 310VDC how can i reduce that

 

[DeepOne]

Yes, the unchancy design. But it works with some improvement.

However obtain good functioning of this scheme by way of the increase capacity is a dead-end way.

 

[Syncopator]

Hi Guys, i tried a circuit. the problem is it reaches 310VDC

Of course it will. The capacitor charges to the peak value of the a.c.

how can i reduce that

Remove the capacitor.

 

[kak111]

Like Syncopator said : remove the capacitor.

Then you can count the value Vrms = Vin (bridge)
Irms = Ipeak * 0.707

Look my picture 220ac_dc

Regards KAK

 

[nadre25]

Hi guys, we used a 1n4007 diode and they burned out... a friend told me to use a "Power Diode", is there a particular diode that i should use for this application? Thanks!

 

[kak111]

Diode 1N4007 is only for current smaller than 1Amp.

Normally starting motor well need current like 5...10 times Inom.
(= current value in motor data plate )
This starting current varies for different motor types .

I suggest you to use 25A 600V diode bridge ( or even 35A 600V)
They have relatively low price.
Ask your dealer general diode bridge for those values ,
price should be about 5$.

Without knowing your motor type, it is wise to connect
one diode parallel to motor anode to bridge plus and cathode to
bridge minus for killing voltage spikes from motor. ( 3A 600...800V)
( must, if your motor have brushed type.)
(Or use so called spark killer RC circuit for 600 volts )
And dont forget put the fuse before your diode bridge.

Regards KAK