Fixed Power; Frequency Droop - Deif GPC-3 Designers Reference Handbook

GPC-3 DRH 4189340587 UK

3.4 Fixed power

This regulation mode is typically used when the generator is running parallel to the mains. During fixed power
operation, the genset cannot change the frequency because it is maintained by the grid. If the fuel supply to
the engine is increased or decreased, the frequency of the genset does not change – only the load will in-
crease or decrease as a result of changed fuel supply.
Dependency
Fixed power mode is active when:
Control inputs Start sync./control
De-load
Breaker feedbacks GB open
GB closed
Mode inputs Fixed P
To activate the use of "Start sync./control" from M-Logic or external communication (for exam-
ple Modbus), the M-Logic command "Start sync./ctrl enable" must be activated. Alternatively,
you can use the functions "Remote GB ON" and "Remote GB OFF".
Never mix the two control methods! If "Remote GB ON/OFF" control is used, you must uncon-
figure "Start sync./control", and vice versa.
Regulator
The power regulator is active in this mode. During fixed power operation, the set point is typically adjusted in
the display (menu 7051).

3.5 Frequency droop

This regulation mode can be used on various occasions where it is required that the generator frequency
drops with increasing load.
The governor droop has the purpose of applying stability in the regulation of the engine and
does not give an actual droop if a controller (GPC-3) is installed.
The GPC-3 droop has the purpose of causing an actual speed droop. With this droop activated,
the frequency will actually change with changing load.
DEIF A/S
Input
25
43
26
27
User def.
Active mode
Fixed power (w/sync.)
ON
OFF
OFF
ON
ON
Functional descriptions
Fixed power (de-load)
ON
ON
OFF
ON
ON
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