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# How can i increase amperes ? Answered

I am making a college project for science fair, and i have made a generator with DC motor of 24v, 0.33 amp and 7.92 watt. When i rotate the motor it gives 24-27 volt of dc voltage. Now i want to convert that DC voltage into AC by connecting a converter of 12 volt, 7 amp. I have made i rectifier which converts the 24 dc into 12 dc voltage, but when  the converter does not start. Can you please tell me what may be the faults? If the apms  are less, can i increase the amps? If the amps are 0.33 can i increase them to 7 amps?

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Well you just can't convert 24 volts, 0.33 amps, 7.92 watts, to 12 volts, 7 amps, 84 watts, no mater what you do.

24 x 0.33 = 7.92

12 x 7 = 84

Even at 100% the best you can do is 12 volts 0.66 amps.

To get 7 amps you need to reduce the voltage to 1.13 volts.

If i reduce the voltage, the converter which needs 12 volts and 7 amps to run will not function.

Now what about if i uses a dc motor of 24 volts, 200 watts which will be of 8.33 amps, will it be possible that the converter can convert the DC voltage of around 24-27 volt into AC voltage.

That might work.

At 50% efficiency you get 100 watts and that should be plenty to run a 84 watt circuit.

Remember since you are using a motor as a generator at best you can produce 50% of the motors capacity.

"Remember since you are using a motor as a generator at best you can produce 50% of the motors capacity."

I don't disagree, but why is that? What losses are present inside a motor being used as a generator? Is it because the output mechanical power is 80%ish less than the input electrical power due to losses and running it the other way (maximum nominal speed and mechanical power) and that 20%ish loss goes the other way?

Sorry for taking so long I was on the road.

Car alternators are only 50 to 60% and they are made for generating electricity, most high efficiency generators only produce 80%.

Without knowing the motor or conducting tests on the motor 50% is giving it some benefit of the doubt.