Woodward 2301E-ST, Инструкция по установке и эксплуатации

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Manual 26694 2301E-ST
Woodward 86
Droop/Isochronous
Load Sharing on an
Isolated Bus
Droop/isochronous load sharing combines the first two modes. All
generator sets in the system, except one, are operated in the droop mode.
The one unit not in droop is operated in the isochronous mode. It is known
as the swing machine. In this mode, the droop machines will run at the
frequency of the isochronous unit. The droop and speed settings of each
droop unit are adjusted so that each generates a fixed amount of power
(see Figure 4-9). The output power of the swing machine will change to
follow changes in the load demand. Maximum load for this type of system
is limited to the combined output of the swing machine and the total set
power of the droop machines. The minimum system load cannot be
allowed to decrease below the output set for the droop machines. If it
does, the system frequency will change and the swing machine can be
motored. The machine with the highest output capacity should be operated
as the swing machine, so that the system will accept the largest load
changes within its capacity.
Isochronous Load
Sharing on an Isolated
Bus
Isochronous load sharing operates all generator sets in a system in the
isochronous mode. Load sharing is accomplished by adding a load sensor
to each electric isochronous control system. The load sensors are
interconnected by the load sharing lines. Any imbalance in load between
units will cause a change to the regulating circuit in each control system.
While each unit continues to run at isochronous speed, these changes
force each machine to supply a proportional share of power to meet the
total load demand on the system (see Figure 4-10).
Released