Alteration of MV Generator to LV Generator

Anything is possible.

I agree with SE, just run the generator at a slower speed, 1500 RPM for 4 pole or 3000 RPM for 2 pole and then feed the generator output through a 4KV to 415V three phase transformer. Here 3.3KV transformers are around and on the top tap they may go high enough to accept 4KV

I have built motor generator sets to change the frequency from 60 to 50 Hz and at the same time using a 600V 60 Hz motor through a stepdown pulley system to obtain 415v 50 Hz. A 1.6MVA belt drive may be pushing it but a large gearbox will do it easily

I also rewound an alternator to step from 50 Hz to 150Hz, again with a pulley stepup, for the excitation of 11000 to 415V transformers with a higher frequency to show up interwinding faults.

That will change the voltage,but not the frequency.

That would require a huge VFD or a rotary phase converter.$$$

In a generator the frequency is determined by the pole arraignment and the RPM..for a 4-post generator, an engine speed of 1,800 rpm produces 60 Hz., and an engine speed of 1,500 rpm yields a frequency of 50 Hz.

To change the frequency of the existing alternator would require changing the number of fields in the stator.

If the slots are arranged appropriately,it can be accomplished by having the alternator rewound to generate 60 Hz by changing the slot pitch,for instance.

This is usually about 60% of the new price,based on a simple rewind price.

That's only if you have no throttle control...

https://www.generatorsource.com/Generator_Frequency_Conversion.aspx

True...True...

Of course it is possible. However, unless this generator was designed to produce different output voltages by switching windings from serial to parallel the redesign and fabrication costs will likely quickly exceed the cost of adding a suitable transformer.

...or even that of purchasing the correct equipment for the job in the first place.

The cost of a total rewind is usually about 2/3 the cost of a new motor/alternator.

This will require a complete rewind,with a different slot spacing.

Of course,there is the possibility of increasing the motor speed by 20% to get 60 cycles, then use a transformer,but the speed regulator would need to be modified,and the motor reliability and lifetime will decrease,as well as vibrations and harmonics,and the voltage will also increase by the same amount.

Give these people a call,they can help you decide the best route:

http://www.gohz.com/use-50hz-alternator-in-60hz-system

Good luck!

At a constant <...16kVA...> the current in the windings goes up by a factor of nearly 10 as a result of the proposed change, so the existing windings may prove unsuitable.

However, the required duty of the alternator at <...415V...> has been withheld from the forum.

So, the best solution is to contact the original manufacturer for advice and, if necessary following the discussions, present the equipment for rewinding.

you still need 1600KVA?Theoretically possible but practically a difficult job.U have to handle higher current for same 1600 kva out put so need larger conductor and so on.with existing slot size and combination one has to re design but for same out power difficult.

I agree the best option may be to sell your existing generator and purchase one suited to your purpose by design.

Anything else is going to be expensive and probably a headache to maintain.

When something goes wrong,everyone involved will form a circle and start pointing to the guy next to them.

A genuine round table of blame.

Do you really want a piece of equipment that will haunt you,with no factory support or parts?

Here is a link to a site that buys and sells generators,so it may be possible to work out a deal with them.

The actual cost may surprise you when considering the alternatives of a hack-job.

http://csdieselgenerators.com/Used_Generators.html?sortby=kW-desc