Actually the other day i started concidering the alternator as a more plausible solution. The only problem is then my motors will be under driven at 14v instead of 18v. Is there any way to use an alternator but jump up the voltage to 18v rather than the 13.5-15 that usually come from them?
Also i dont quite understand the field current stuff. Like i have to supply field current to it, then the current/ voltage output depend on my supply?
Thanks so much everyone for your help.
Its really appreciated
Oh and about my checking efficiency. Im almost certain my method is flawed, It doesnt seem right at all. All ive done is run one motor into the other and check the input voltage against the output voltage with the motor acting as a generator running a halogen lamp.
I got output voltages from the generator motor that were 90% of the feed voltage running into the first motor.
I know i know. Its not that easy.
But i was just mostly trying to get an idea of rpm needed to produce certain voltages. And this was just making sure i could produce a good voltage before i ordered the engine. (which i now have in my possession)
Thanks again
Craig