Drift in Synchro
Drift in Synchro
(OP)
Hello,
I have 2 generators running in parallel. I was doing an off load test+synchro. The gensets entered in parallel on the busbar with no problem.
However, after a few minutes, i started reading the power on the circuit breaker digital trip unit: one generator was producing positive power while the other was receiving the same amount but in negative.
There is a return power protection realy set at 10% of full rated kW.
With time, the active power produced by one of the generator kept increasing while the other was decreasing at the same rate. I expected the automatic synchro system to do something about this, but instead it let the system drift until after 19 minutes the system triped because of excess return.
My question is what could be the problem in this case? is it the controller in the synchro panel? or just a bad setting somewhere?
I have 2 generators running in parallel. I was doing an off load test+synchro. The gensets entered in parallel on the busbar with no problem.
However, after a few minutes, i started reading the power on the circuit breaker digital trip unit: one generator was producing positive power while the other was receiving the same amount but in negative.
There is a return power protection realy set at 10% of full rated kW.
With time, the active power produced by one of the generator kept increasing while the other was decreasing at the same rate. I expected the automatic synchro system to do something about this, but instead it let the system drift until after 19 minutes the system triped because of excess return.
My question is what could be the problem in this case? is it the controller in the synchro panel? or just a bad setting somewhere?






RE: Drift in Synchro
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I don't suffer from insanity. I enjoy it...
RE: Drift in Synchro
RE: Drift in Synchro
What type of governors and load control do you have?
respectfully
RE: Drift in Synchro
Actually the isochronous speed control requires the activation of a PI regulator. So two PI regulators working indipendently on the same system bring it exactly to the unstable condition you described.
The off-load test makes the system much more unstable because no damping element (=resistive load) is connected.