Alternating current generator from 50 Hz to 60 Hz 2

[21121956]

Hello everybody:

Even when I am a Mechanical Engineer, here it goes my query:

There is a Diesel Generator genset, driven by a reciprocating turbocharged engine, Vee and 16 cylinders, delivering 13.000 kW and running at 500 RPM. This engine drives an alternating current generator, which supply an electrical net in 11 kV, 16.421 kVA, power factor of 0,8 at 50 Hz.

It is planned to put into operation this genset working in parallel with others that run at 514 RPM and are engaged to the grid delivering 17.000 kW, at 13,8 kV, 22.500 kVA at 60 Hz.

The questions are:

1. Is it possible that this genset (just as it is now) can work properly in the grid of 60 Hz without any change and or modification, either in the engine, or the generator?

2. If the answer to question 1 above were yes, is it possible to expect that the generation of the same 13.000 kW can occur at a voltage of 13,8 kV and 60 Hz, or is it necessary to install a transformer bank?

3. Is there any problem with the speed of rotation of the genset, 500 RPM, in order to achieve this task in the grid of 60 Hz?

Any suggestion, comments, an address of a site on the web will be highly appreciated.


Thanks in advance

 

[electricpete]

3. Is there any problem with the speed of rotation of the genset, 500 RPM, in order to achieve this task in the grid of 60 Hz?

Not sure if I understand your question. I should be obvious that you will need to increase speed of a sync generator from 500rpm to 600rpm in order to increase the frequency from 50hz to 60hz.

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[slavag]

Hi.
If your's generator voltage is 11kV "IS NOT POSSIBLE"
connect it to 13.8 grid, you must step up trafo.
for the other issues please see attached
thread238-205627
thread237-213507
Regards.
Slava

 

[21121956]

Hello everybody:

Thanks electricpete for your quick response.

In the beginning I tought it would be necessary to increase (i.e. via gear box) the RPM from 500 to, let us say, 514 or even 600 RPM but, for this change it would be imperative at the same time to perform modifications in the number of poles of the generator.

The medular point of this query is to get to know what modifications/equipment addendum are required to put this genset into operation in the grid at 60 Hz. Or maybe, the answer is NO, it is not possible and it would be necessary to ghange the generator in order to use that recip engine.

Once again, thanks

 

[waross]

Check with the engine manufacturer as to whether the engine will operate at the higher RPM.
Check with the manufacturer as to to rated power output of the engine at the new speed.
I am not sure of the turbo performance at the increased speed. Hopefully someone else will comment.
Investigate as to whether the 11 kV windings will sustain 13.8 kV.
The rated voltage at 60 Hz, based on the V/H ratio will be 13.2 You will be about 4.5% above rated voltage. This increase is within the allowable tolerance of most generators.
The kW output will depend on the available power from the engine.
The simple answer is that a 13,000 kW machine at 50 Hz. will upgrade to 15,600 kW at 60 Hz. but it is not quite that simple.
There are several questions and answers based on factors that you haven't mentioned.
Search eng-Tips.com
This subject has been discussed.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[davidbeach]

You'll either run the engine at 600 rpm or it won't be "this genset". You won't be changing the number of poles in the generator, that will require a different generator.

It is always easier to go from 60Hz to 50Hz at 5/6 the voltage than to go the other direction. If you're lucky the set has both 50Hz and 60Hz ratings, but at that size I doubt it.

 

[21121956]

Hello everybody:

Thanks for all your comments on this subject. The links submitted in this thread have been of paramount value.

slavag and waross, stars for you.