Synchronizing Two Generators of 1800RPM Speed and 1200RPM Speed


Thread Starter


Hello, I am new to this forum.

On the platform where i work we have a caterpillar diesel generator that runs at 1800rpm, 60Hz, 480VAC and 3 waukesha gas engine that runs at 1200rpm, 60Hz, 480VAC. The waukesha engines can all be synchronized together. I want to know if it is possible to synchronize the caterpillar engine of 1800rpm into the bus bar of the waukesha gas generators.

Your help is highly appreciated to giving me a clue on the possibility of solving this problem. I can also give more information if needed.

Rukevwe, Nigeria.

The simple answer is yes. But, first insure that the existing switch-gear fault-duty (especially ground-fault) is not exceeded with the CAT gen-set connected to it, while the others are operating.

Phil Corso
Thanks Phil,

i would look into it. Is there any synchronisation unit you can recommend for me?

I am so grateful for your help Phil but i still have some questions. The harmonics, how harmful can they be? I guess they would increase the kVar and also cause the heating up of the windings. Is there a way of reducing it?

All generators are rated at 800kW.
Rukevwe... I purposely omitted detail regarding the effect of paralleled alternators having dissimilar design features, winding-pitch being just one.

I thought you should first deal with the most costly factor; i.e., Switch-gear Fault-Duty. The information to answer this concern is more readily attainable than that needed for the effect of winding-pitch. Secondly, there are techniques to ameliorate such effects.

If other Forum posters are interested, I can present a stand-alone thread, entitled, "The Physics of... Circulating-Current Between Paralleled Alternators."