3 phase generators 1

[Dials]

I have an engine drive 22kw induction 3 phase generator, commercially made, which will not generate any voltage. It has been flashed while turning at rated speed and above with 12 and 24 vdc without results. The generator has been removed for the engine and been flashed with the 12 vdc which has pulled the rotor to the field coils. After assembly the unit still does not produce voltage. All help is appreciated.
Thanks
Dials

 

[BJC]

Yellow Pages - Generator Repairs.

 

[DRWeig]

Dials,

If it's an induction generator, it needs to be connected to an active voltage source, it cannot produce voltage on its own like a synchronous machine...

Is this a possibility? You used the word "Induction" in your post...

Old Dave

 

[Dials]

Old Dave,
I have been lead to believe that with a capacitor bank it will generate it’s own voltage?
Dials

 

[ccjersey]

Possibly it might generate some voltage, but you are trying to do something which like you, I have heard about being possible, but isn't supposed to be easy or a certain thing. Maybe it needs a different capacitor bank. If you get it to develop voltage, that may be the easy part. Loading it will tend to drop the voltage back down.

Where did you get this thing? Why do you have it instead of the more common AC generator if you don't have it connected to the grid. What type of capacitance do you have on it?

Can you try it paralleled to the grid and see if it works like that.

Jim

 

[aolalde]

A capacitor will never make an induction generator to operate.

You need three phases AC matched to the generator voltage to generate the magnetic rotating field that will interact with the rotor winding cage only when the rotor speed is above the field synchronous speed.

 

[mc5w]

Actually, a single phase AC voltage applied to a 3-phase induction generator will make it act as a combination generator and phase converter. However, all of the magnetizing current will be coming through 2 of the 3 wires which will impair capacity.

Power companies are not really keen about induction generators even though the voltage automatically collapses during a power failure which makes electrical safety easy. Induction generators draw heavy amounts of magnetizing current - wind farms have to be equipped with rapid response reactive compensation capacitors for this purpose.