Woodward DSLC, Installation And Operation Manual, Page: 64 / 114

DSLC Digital Synchronizer and Load Control Manual 02007
58 Woodward
10. Alternately disable the VAR/PF Control by selecting “Manual” and raising or
lowering voltage to shift the power factor away from the PF Reference, and
then switch the mode back to “Auto”. This switching will cause a disturbance
to aid in doing the following dynamic adjustments.
An alternate, but less convenient, method of creating a reactive power
disturbance is to switch VAR/PF Control Mode to Disabled, manually
change voltage to get an offset in power factor or kVAR load, and then set
VAR/PF Control Mode to the desired operating mode of PF Control or VAR
Control.
11. If the control action is too slow to bring the PF or kVAR load into control,
increase the VAR/PF Gain. If increasing the gain results in instability,
decrease the VAR/PF Stability. If the control action is too fast, reduce the
VAR/PF Gain. If overshoot of the set point occurs, increase VAR/PF
Stability.
Repeat adjustments of VAR/PF Gain and Stability until satisfactory control
of the reactive load during transients is obtained.
12. Select the desired operating mode, either PF Control or VAR Control. Set
the appropriate reference for the desired operating point.
13. Ramp load up and down throughout the expected normal load operating
range. The power factor or kVAR load should smoothly control with only a
small time delay.
14. Set the PF Deadband set point to minimize control response to small
variations in power factor. This is especially important in systems where a
MOP is used for voltage adjustment, to prevent excessive wear of MOP
components.
15. If desired, set the voltage trim function to enabled. Set the voltage regulation
to the desired percentage. If enabled, the DSLC controls operating in
isochronous automatic power factor sharing mode will adjust the bus
voltage to the voltage reference (within the voltage regulation percentage)
before making corrections to share power factor.
16. When you have obtained satisfactory performance of the VAR/PF Control,
press the “SAVE” key on the Hand Held Programmer.
17. Record values of set points in Appendix A for future reference.
When the VAR/PF Control is enabled for either PF Control or VAR Control,
power factor sharing will be done automatically when in isochronous load sharing
mode.
This completes VAR/PF Control adjustments.