Power output of a theoretical generator

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To determine the power output of a theoretical generator, the basic equation is Power equals Voltage times Amperes. Voltage can be calculated using the back EMF constant, which is the product of the field flux and generator speed. The current output is influenced by the load connected to the generator and the armature's ability to dissipate heat, which is determined by the armature resistance. Efficiency plays a crucial role, with most generators operating at about 90-95%. Understanding these principles allows for the estimation of both voltage and current in a theoretical context.
topcatthomas
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so, assuming that you know all of the aspects of your theoretical generator, apart from the voltage and current, how would you work it out. I know that it is possible, but i can't find anything that I understand, or is even valid online. There should be some equations i can use to work it all out, so what are those?
Thanks.
please could you use word equations as I may not know what the symbols mean.
 
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The power output of a generator, in a "wordy equation" would simply be:
Power equals Voltage times Amperes.

Or are you asking what the maximum power output would be?
 
OmCheeto said:
The power output of a generator, in a "wordy equation" would simply be:
Power equals Voltage times Amperes.

Or are you asking what the maximum power output would be?
Yes, but how do you work out the voltage and current? I can't measure it if it isn't real.
 
topcatthomas said:
Yes, but how do you work out the voltage and current? I can't measure it if it isn't real.
I don’t understand, why isn’t voltage and current real.
 
topcatthomas said:
Yes, but how do you work out the voltage and current? ...
Voltage is equal to the rate of change of a magnetic field. Typically in the presence of a conductor, from what I hear.
 
topcatthomas said:
so, assuming that you know all of the aspects of your theoretical generator, apart from the voltage and current, how would you work it out. I know that it is possible, but i can't find anything that I understand, or is even valid online. There should be some equations i can use to work it all out, so what are those?
Thanks.
please could you use word equations as I may not know what the symbols mean.
Welcome to the PF. :smile:

Can you say what your application is? It's a bit hard to help you without knowing more. Especially if you want the description without any equations -- that is especially challenging, but we will try out best if you can tell us more about what you are trying to do.
 
Even without your background, I can tell you that the current depends on the load, not the generator. Zero load zero current.
 
topcatthomas said:
please could you use word equations as I may not know what the symbols mean.
Also, are you comfortable with basic equations like Ohm's law: V = I * R and the definition of electrical power, P = V * I ? That would be a big help if you are okay with those basic equations. :smile:
 
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Don’t know if this helps you, but 1 Horsepower is about 746 Watts, and most generators are about 90-95% efficient. So, a 10 HP generator will probably give you about 7 KW. Is that what you were asking?
 
  • #10
The output voltage depends on the type and design of the generator. Things like the number of turns in the windings, the flux density and the rpm.

The current drawn depends on the load connected to the generator. What you probably want to know is the maximum current that the load can be allowed to draw. Fundamentally that is limited by the power input to the generator, the voltage and the efficiency of the generator. Practically it depends on the design of the generator.

What type of generator are you talking about?
 
  • #11
CWatters said:
What type of generator are you talking about?
a fictitious one

topcatthomas said:
so, assuming that you know all of the aspects of your theoretical generator,
 
  • #12
topcatthomas said:
...assuming that you know all of the aspects of your theoretical generator, apart from the voltage and current, how would you work it out?
You would calculate the back EMF constant (Kω) of the generator. The no-load output voltage is then equal to x field flux x generator speed.
 
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  • #13
The current capacity of a generator depends on how quickly the armature can dissipate heat. The rate at which heat is produced = current2 x armature resistance. The maximum current output that still permits reasonable lifespan is estimated by the design engineer based on experience and then verified with lab testing.
 
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