25 MW motor fed by off grid diesel plant

[ters]

A 140 MW diesel plant will consist of 14 units, 10 MW each (or a similar combination). It will operate off grid and will be feeding a large industrial facility. Among many problems still be solved, one of them appear to be very severe – the load will mainly consist of various large motors, whereas one of them will be in the range of 25 MW, which approximately corresponds to the size of 2.5 diesel units, while two other motors are in the range of 15 MW, which approximately corresponds to the size of 1.5 diesel unit.

Assuming that all units and the entire load will be (one way or the other) on the same bus, and that diesel units are equipped with very responsive AVRs and governors, the load sharing is optimized, etc, how likely is that such configuration can function at all and still maintain voltage and frequency at tolerable levels (whereas the “tolerable” is still to be defined)?

It is assumed that the mechanical load of each large motor can be applied reasonably gradually, however, in case that a breaker feeding any of such large motors trips, loosing something like 20% of the load (in case of largest motor) will obviously have a large impact on the frequency and voltage stability.

We have not done any modeling yet. The maximum load is in the range of 80% of the total installed generating capacity.

 

[davidbeach]

80% load sounds high, but with an appropriate definition of "acceptable tolerance" on voltage and frequency you should be able to make this work.