Hi Azril,
Base on my own working experience,the causes of reverse power in turbine generator can be attributed to:
1. improper position / incorrect polarity wiring of C.T
in the generator or generator sychronization
panel to reverse power relay( it happen in a
newly install generator or panel)
2.it can been experience if one of generator in
synchrization have a decrease voltage and frequency
discrepancy, which will resulted to the generator to
work like motor, also affect direction of flow
current in primary and secondary side of c.t and it
resulted to reverse power fault.
Rgd
DAPOTITI