Woodward DSLC, Инструкция по установке и эксплуатации

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DSLC Digital Synchronizer and Load Control Manual 02007
52 Woodward
7. Close the Load/Unload switch. Load should increase smoothly to the Base
Load setting. Load will normally lag slightly behind the reference during
ramping. If the lag is excessive, increase Load Control Gain by a factor of
two. If a slow hunt is observed during the ramp, or if overshoot of the Base
Load setting occurs, increase the Load Stability by a factor of two.
8. Ramp the load up and down by alternately opening and closing the
Load/Unload switch. Be sure to reclose the switch before load drops to the
Unload Trip level or the DSLC control will issue a command to open the
circuit breaker. Adjust Load Control Gain and Load Stability to get the
desired performance.
NOTE
Correct dynamic adjustment may be more easily observed if the Load Ramp
Time set point is set somewhat faster than will be used in service.
9. In power systems experiencing rapid fluctuations in power (such as digester
gas fuel systems), reducing the Load Control Filter set point will reduce
control sensitivity to the fluctuations. Slower, but more stable, performance
can be obtained.
10. In most systems it will not be necessary to change Load Derivative from the
default value of 0.0 seconds or Load Control Filter from the default value. In
higher performance systems, the filter frequency may be increased for
greater control bandwidth, and Load Derivative may be increased to
increase the rate of change in Speed Bias Output during a transient.
This completes the integrating load control setup. Continue with Isochronous
Load Sharing Adjustments or Final Load Control Setup if Base Load is the only
operating mode to be used.
Isochronous Load Sharing Adjustment
This procedure sets up and verifies the isochronous load sharing mode of
operation. In Isochronous Load Sharing, the unit load is compared to the system
load to generate a proportional error signal to safely operate in parallel with
another system. An isolated load sharing bus may be used to do this setup for
simple load sharing systems.
This mode is also selected when operating as a slave, when another DSLC
control, operating in the process control master mode, is used to set the system
load level. The unit may be paralleled against a utility bus to do this slave setup,
as long as a master DSLC control is paralleled to the utility bus with the slave
unit.
1. Verify the Menu 2 Rated Load set point is set to the desired 100% load
rating of the machine. Load sharing is on a per-unit basis to allow for
differences in the kW rating of various machines in the system. For
example, assume system load demand is 50% of the capacity of the units
operating in the load sharing mode. If one unit's Rated Load is 100 kW, that
unit will be operating at 50 kW. If another unit's Rated Load is 500 kW, that
unit will be operating at 250 kW, etc.
2. Select the Menu 0 Active DSLCs set point. Verify that the number displayed
corresponds to the number of DSLC controls currently installed and
powered up.