Microturbine Generators - Fault Current

[tonycatterall]

We are proposing to install MTG's on an offshore platform. The units will be Capstone C60. The only drawback seems to be the low level of fault current available. The generator output is via an inverter and this limits the fault current to 200% Ifl, in this case about 145Amps. We are proposing running three units and this should provide around 435A. Even so, this still limits the max downstream circuit fuse to 50A (to ensure fault clearance <1sec). This obviously imposes limits on equipment loads.

My question is, has anyone out there had similar problems, and if so is there another solution for increasing the fault current level?

 

[davidbeach]

Fuses are probably not the best choice for this application. Relays will give better detection of low level fault currents. On the other hand, won't the micro turbine shut down when the output of the inverter is shorted?

 

[cranky108]

You also need to consiter what happens if one or two of these are out of service before a fault occures. This will lesson your fault current even more.

Usually we are trying to lower fault current, not rase it.