Reactive power ramp down
This parameter defines the speed of the ramp down of the genset active power when the fixed power set point changes or when the
genset disconnects from the busbar. This reduces the mechanical strain on the genset and breaker when the breaker opens and the
genset stops supplying power to the system. Limiting the power ramp down speed also increases the system stability.
The parameter consists of one curve. The curve can consist of 2 to 10 coordinates for the time and the percentage of the genset
nominal reactive power.
Parameter Range
Default ramp 1 Notes
[s]
0 to 3600 s 0 s; 20 s
The time coordinate for the reactive power ramp down curve.
[%]
0 to 100 % 100 s; 0 %
The percentage of nominal reactive power of the genset coordinate for the reactive
power ramp down curve.
Reactive power ramp down example
You want a 100 kvar genset to ramp down to 50 % of its nominal reactive power at 10 %/s, and 5 %/s between 50 % and a
0 % of its nominal reactive power. This means that it will take at least 15 seconds to ramp down the genset reactive power
from 100 kvar to 0 kvar.
The coordinates for the power ramp up curve are: (0 s; 100 %), (5 s; 50 %) and (15 s; 0 %).
This means that the controller regulates the genset to ensure that the reactive power ramp down does not exceed 10
kvar/s between 100 % and 50 % of the genset's nominal reactive power. And the controller regulates the genset to ensure
that the reactive power ramp down does not exceed 5 kvar/s between 50 % and a 0 % of the genset's nominal reactive
power.
If the genset reactive power is 50 kvar, and 0 kvar is required from the genset, it takes at least 10 seconds to ramp down
the genset reactive power.
If the genset reactive power is 70 kvar, and 0 kvar is required from the genset, it takes at least 12 seconds to ramp down
the genset reactive power.
6.6.2 AVR analogue regulation function
You can configure an analogue output on the controller to regulate the AVR. You can also set a number of parameters for the AVR
analogue regulation function.
Wiring example
Figure 6.6
Example of analogue output wiring for AVR regulation
Regulators > AVR > AVR output [%]
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