Risks when using only frequency for running detection
It is possible to only use frequency for running detection. However, using only frequency for running detection increases the risk of
not detecting that the genset is running.
The software only uses the frequency measurements when the voltage is at least 10 % of the nominal voltage. This could cause
trouble, since the voltage does not necessarily increase linearly with speed (this depends on the AVR).
If the frequency curve for the genset start up has a dip around the detection set point, the controller can interpret the dip as no
running detection, and stop the genset. Increasing or decreasing the set point away from the dip would solve this problem.
Frequency running detection example
A genset start up frequency curve is given below.
50
10
30
0
20
40
Frequency
[Hz]
Time
[s]
2
1
1
2
3
4
4
3
1. Crank begins.
2. Fuel in.
3. If the running detection set point is 30 Hz, running detection is ON.
4. If the running detection set point is 30 Hz, the frequency drops 2 Hz below the set point, and running detection from
frequency is OFF.
•
If there are no other running detection inputs, the controller immediately deactivates the run coil and/or activates the
stop coil.
8.2.5 Regulation
The GENSET controller can regulate both a governor (GOV) and an AVR.
More information
See
Regulation
for more information.
8.2.6 Power management
The GENSET controller works together with the other controllers in the system to provide efficient power management. This includes
blackout prevention and blackout recovery.
More information
See
Power management
for more information.
DESIGNER'S HANDBOOK 4189340911K UK
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