Range Relay position Notes
the deadband value. The [Regulator] increase* and [Regulator] decrease* relays remain
deactivated continuously.
See point 6 on the figures below.
*Note: [Regulator] is either GOV, or AVR.
If the output is in either the constant or the variable range, the controller activates the configured relay (governor increase or
decrease, or AVR increase or decrease) for the required time. The figures below show how the time decreases from the value set for
Period time to the value set for Minimum ON time as the measured value gets closer to the set point for high Kp values and low Kp
values. The Maximum ON time parameter is set to 100 %.
Figure 6.2
Up and down relay on time for different deviations from the set point
Frequency [Hz]
Relay up
on time [%]
Relay down
on time [%]
100
50
100
50
75
25
25
75
High Kp
Low Kp
1
2
3
4
5
6
Figure 6.3 Relay action based on measurements at the end of the period time
min
min
min
min
Period [ms]OFF
ON
min
Relay
status
1 2 3 4 5 6
Period time
Pulse properties
A relay control pulse has three main properties:
• Period time
• Minimum ON time
• Maximum ON time
The Period time is measured from the start time of one pulse to the start time of the next pulse.
DESIGNER'S HANDBOOK 4189340911K UK Page 172 of 521
To Next Page
Loading...
