what is a difference between low forward power and reverse power in generator?

Here is some background on reverse power...forward power should be the opposite

Reverse kVAR- Reverse kVAR can happen when the gen set has lost excitation and the system returns vars to the gen. If the load has a leading power factor the gen set will also see a reverse power factor.

Reverse power - watts and vars well reverse power combined with power factor. watts don't eqaul vars

When will it happen? - Leading Power Factor can be a cause. Very low loaded UPS with power factor correction that serves pdu's with power factor correction built into, combined with all the induction motors having vfd's will have a leading power factor. the common one is loss of excitation

how will it affect the alternator? - it will induce currents in the rotor at 120hz or 100hz if your in Europe. also the impedance of the rotor sturcture is so high that when you have you I^2R the heat build up can start to weld.

What should be done during reverse...? - When that happens the gen set should be disconnected from the system.

thanks.

Can we trip steam turbine also? At present we are not tripping turbine during reverse power only gen.breaker is tripping.