Applications Using a Ramp Generator
The Ramp Generator slows the speed change between idle and rated speeds. It
has no effect on steady-state speeds. Once set it provides a constant speed
change per second by biasing the speed reference when changing from idle to
rated and vice versa. The accel and decel pots control the rate of change.
Acceleration and deceleration times depend on accel and decel pot settings and
the difference between idle and rated speeds.
Paralleled Generator Applications
A Load Sensor is used with the EPG for isochronous or droop paralleling.
With an isolated bus, isochronous load sharing is usually chosen. In an
isochronous load sharing system, the load gain signal voltage is shared with all
other controls through paralleling lines, and provides an average load gain signal
used by the controller circuits.
EPG Electrically Powered Governor Manual 82493
22 Woodward
By comparing the paralleling line voltage to its own load gain voltage, the
controller calculates an output to raise or lower, as necessary, the generator
output to make the load gain voltage of its unit equal to the paralleling line. Load
Sensor output directly biases the speed loop controller circuit of the speed
control to affect the actuator fuel level setting and precisely maintain its
proportional share of system load while maintaining a fixed frequency. See
Figure 2-8, Additional Wiring to Install the EPG Load Sensor.
Droop operation is required when paralleling with an infinite bus or units not
having compatible electric governors. The Load Sensor and Speed Control can
be in isochronous when used against an infinite bus with a Generator Loading
Control or Import/Export Control. The Droop signal then comes from either the
Generator Loading Control or the Import/Export Control.
