Woodward 2301E-ST, Инструкция по установке и эксплуатации

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Manual 26694 2301E-ST
Woodward 83
INLET
SPEED
REFERENCE
kW SENSOR
CIRCUIT
LOAD
MATCHING
CIRCUIT
CB AUX CONTACTS
LOAD SHARING LINE
LOAD SIGNAL
2301D-ST
VALVE DEM AND
Generator Turbine
STEAM
TURBINE
EXHAUST
A
B
C
Figure 4-6. Paralleling System
An auxiliary contact on the generator breaker connected to the discrete
input is used to select speed and load control operation. When the input to
the 52G BREAKER contact is open, the control is in droop speed control.
When the 52G BREAKER contact is closed, the control is in isochronous
load control or droop control.
The Load sensor computes the load carried by each phase of the
generator. The current load on each phase is multiplied by the cosine of
the phase difference between the current and the voltage and the three
phases are added to determine the total load.
The output of the load amplifier is adjusted by the load gain set point. By
setting the load gain voltage on each unit to the same level at full load,
proportional load sharing is achieved. Regardless of differences in
generator set capacities in the system, each generator set is loaded to the
same percentage of its capacity. A final adjustment of the individual load
gain adjustment will compensate for minor differences in the generator
sets.
Droop mode allows operation of a generator on an infinite bus or in parallel
with other turbine generator units using hydro mechanical governors. In
droop, speed changes as the load on the generator changes. An increase
in load results in a decrease in speed. The amount of speed change or
droop is expressed in percent (of rated speed) and is set by the load droop
set point.
Droop Mode Droop is a decrease in speed or frequency, proportional to load. That is, as
the load increases, the speed or frequency decreases, as illustrated in
Figure 4-7. This reduction in speed is accomplished with negative
feedback. The feedback increases as the system is loaded.
Released