Woodward UG-10 Dial, Инструкция по установке и эксплуатации

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Manual 03040 UG Dial Governor
Woodward 15
Too little droop can cause instability in the form of hunting, surging, or difficulty in
response to a load change. Too much droop can result in slow governor
response in picking up or dropping off a load.
Using an example where the governor speed is 1500 rpm at no load and 1450
rpm at full load, droop can be calculated with the formula:
%Droop =
No load speed – full load speed
full load speed
x 100
%Droop =
1500 rpm – 1450 rpm
1450 rpm
x 100 = 3.5%
If the decrease in speed is greater than 50 rpm when the governor output shaft
moves from the minimum to the maximum fuel position, droop greater that 3.5%
is shown by the governor. If the decrease in speed is less than 50 rpm, droop
less than 3.5% is shown by the governor.
If the governor output shaft does not use the full 30° of available
travel from “NO LOAD” to “FULL LOAD”, droop will also be reduced
proportionately.
Marks on the droop adjustment scale on the dial panel are reference numbers
only, and do not represent droop percentages. Thus the 100 mark does not
represent 100% droop. It represents the maximum droop percentage available
on that particular UG governor model.
Speed droop consists of a control knob, cam, and linkage, which when preset,
varies the compression of the speeder spring as the output shaft rotates.
Increasing the fuel reduces speeder spring compression and, in turn, the
governor speed setting. The unit gradually reduces its speed as load is applied.
This relationship between load and speed acts as a resistance to load changes
when the unit is interconnected with other units either mechanically or
electrically.
Reducing droop to zero allows the unit to change load without changing speed.
Normally, set zero droop on units running alone. On interconnected units, set the
least amount of droop possible to provide satisfactory load division.
For ac generating units tied in with other units, set droop sufficiently high
(reference numbers 30 to 50 on the dial) to prevent interchange of load between
units. If one unit in the system has enough capacity, set its governor on zero
droop, and it will regulate the frequency of the prime mover system. If its capacity
is not exceeded, this unit will handle all load changes.
Operate the SYNCHRONIZER knob of the governor with zero droop to adjust the
system’s frequency. Operate the SYNCHRONIZER knobs of the governors that
have speed droop to distribute load between units.
Operation of the UG Dial Governor
General Information
Refer to Figure 3-1 with the text to better understand the operation of the UG Dial
governor. This schematic diagram is of a basic design and does not include any
auxiliary equipment.