[Date Prev][Date Next]
[Chronological]
[Thread]
[Top]
[PSUBS-MAILIST] Electric engine control
I was gathering ideas about controlling the RPMs of a DC engine. So far I
found two ideas:
1. Controlling the voltage
2. Including a rheostat in the engine circuit (controlling current)
Method #1 is having a system of switches and several batteries. For example,
you have 3 of 12 volt batteries and your main DC engine is 36 volts. You can
change the voltage from 12 to 24 or 36 volts.
It's a good system, but I have a question for people who know more about
electricity and batteries more than I do:
If you drive for a long time on "1-st gear", that would deplete battery #1,
leaving 2 others fully charged. Then when you turn on "3-rd gear", won't it
hurt the depleted battery to be hooked up into the same circuit? Somehow I
feel that the battery will start to charge and you will waste energy. Am I
correct?
Method #2 will give you a much smoother control over the RPMs, but I think I
see two problems with it:
1. Rheostat will become extremely hot
2. You waste energy in the rheostat
Once again: am I correct on this one?
I was also thinking of other probable methods and that's what I came up
with:
For example, you have 12v battery and a 12v DC motor. From battery power can
go to an inverter. Inverter is an opposite of a rectifier — it converts DC
to AC. Then this AC current goes to a transformer with multiple secondary
coils. This way you can have (for example) 4.5v AC, 9v AC and 12v AC outputs
from the transformer. Then it goes to a simple diod rectifier and then to
the motor. This way all of your batteries (if you have several) are used
uniformly and stuff doesn't get so hot as in case with rheostat. The
question is, can you find an inverter that can handle 100+A current loads
and would the energy loss in the inverter and the transformer be less than
in case with a rheostat?
Sincerely, Paul.
_________________________________________________________________
Send and receive Hotmail on your mobile device: http://mobile.msn.com