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Reverse Power
During the testing of reverse power relays (RPR) on board of a tanker was observed that the reading of the reverse power on the kilowatt meter is very small.

Three phase power generation, 440 V AC at 60 Hz. The reading of kilowatt meter was so small that the reverse power relay is not tripping the air circuit breaker(ACB). One generator speed was increased, and another was decreased, expecting the reverse power to reach - 10%.

There were three generators, and this happens only for one generator which does not get the reverse power. Note that the generator alone on the bus bar or in parallel performs well, when in parallel in auto-sharing the power correctly with one or two other generators.
The method to check reverse power is - one generator on bus bar - bring one more generator (tested one) on bus bar through synchronisation - after both generators on bus bar put load sharing control in manual - then decrease the speed of the tested generator, keeping an eye kilowatt meter - expect 100 kW reverse power - achieved only 30 kW - help to the processes by increasing the speed to the second generator - not increase on reverse power - proceed manually for ACB open, with the eyes on the generator engine frequency (speed) - when ACB open the frequency drop at 55 Hz.

Decrease the RPR setpoint and found working accordingly with the kilowatt meter indicator. Please note that the voltage was checked and found satisfactory, mean no problems with the automatic voltage regulator (AVR).

Why the reverse power is absorbed? In the fuel rack of the generator engine? If yes how this perform well when parallel or alone?

Any ideas?

Without thinking too hard wouldn't the reverse power only be what it takes to keep the generator spinning, i.e. like an auto coasting down a hill?

I totally agreed if the engine generator was weak. But it performs well alone and in parallel. If at suddenly high load (like an air compressor, bow thruster, etc) will drop his power, will be maybe turned by reverse power; but I think is not the case.

>Without thinking too hard wouldn't the reverse power only
>be what it takes to keep the generator spinning, i.e. like
>an auto coasting down a hill?