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What happens when a generator is overloaded?

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What happens when a generator is overloaded?

My understanding is a generator produces a voltage and a current.
Voltage is related to the number of windings and the rpm.  Current is related to the resistance of the windings.

I like to know when a generator sees a load exceeding its specs, what happens.


Let's say a generator is designed to produce 100volts at 10amps (1000 watts) at 5000 rpm driven by a 2hp gas engine.

If it is charging a bank of 7 lead acid batteries (84 volts) that wants to draw 15 amps (arbitrarily chosen) at 100 volts. 
a) Will the generator output voltage drop to, say 84 volts and 11.9 amps (still 1000 watts), and the windings eventually get too hot and burn out?  To have lower voltage, rpm drops, right?
b) Will the generator output voltage stay at 100 volts, but current stay at 10 amps (still 1000 watts) because the generator windings is limited at 10 amps?

I think I'm beginning to realize the answer depends on what type of generator is used.  It's like motors being series wound versus shunt wound, or pm, etc.
Can someone explain what are the different types of generators and how they behave?  a) is bad because it burns out.  b) seems

But lets continue with the above example in 3 scenarios:

1) Say the batteries become fully charged and will take only 1 amps at 100volts.
1a) Does the generator output stay at 100volts and 1 amp.  I think so, because when I disconnect the load, I know I will have 0 amps, but I can measre 100volts.

2) Say I connect a second bank identical batteries in parallel to the first bank.
So at 100 volts, they will draw 30 amps.
2a) Will the generator output voltage drop to, say 84 volts and 11.9 amps (still 1000 watts), and the windings eventually get too hot and burn out?
The generator output will not go lower than 84 beause that is the voltage of the battery bank.  But this is exactly the same as case a) at the beginning...so what is the meaning of more load?
b) Will the generator output voltage stay at 100 volts, but current stay at 10 amps (still 1000 watts) because the generator windings is limited at 10 amps?
Again, the load doesn't seem to matter once they exceed the max output of the generator... someone pls help.

3) A different bank of 6 batteries (72volts) that will draw much more current at 100 volts (quick charge).
3a) Will the generator voltage drop to 72 volts and 13.9 amps and burn up much quicker?
3b) Will the generator stay at 100 volts but deliver only 10 amps, which is a slow charge rather than a quick charge.  If 3b) is true, then the generator does not need any regulation circuitry...everything just works out.

Sorry for the lengthy post...as you can see I'm trying hard, but I don't get it.

Danny

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If you are using an alternator or a generator you must have some form of regulator to adapt the energy available to the batterys state of charge. If you do not use any form of regulator there will be damages to the batterys, alternator or both.

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