Siemens SINAMICS S120 System Manual page 76

Commissioning
7.4 Commissioning example for an infeed with voltage and frequency control for an island grid.
Parameter Value
p5401[1] e.g. 1
p5403[0, 1] e.g.:
p5403[0] = r5497[0]
p5403[1] = r5497[1]
p5404[0, 1] e.g.
p5404[0] = r5488[0]
p5404[1] = r5488[1]
p5405 e.g. 100 %
p5406[0] e.g. 0
1)
p5407 e.g. 4 %
1)
p5409 e.g. 150 ms
p5413 e.g. 50 %
p5415 e.g. 100 %
76
Comment
BI: Grid droop control activation - static setpoint activation
For p5401[1] = 1, droop characteristics p5405ff and p5415ff are active. For stable
generator operation, the setting for the no-load points for voltage and frequency
must match the actual operating point of the island grid (especially the load distri-
bution between several power generating units).
For p5401[1] = 0, the no-load points of the voltage and frequency droops must be
internally corrected, so that on the average an apparent power of zero is obtained
at the Active Line Module (parameters p5405/p5406 and p5415/p5416 are deac-
tivated for the no load points).
CI: Line droop control current signal source
If the droop is not to be active for the connection point directly at the Active Inter-
face module, then observe the notes provided in the parameter descriptions.
CI: Line droop control voltage signal source
If the droop is not to be active for the connection point directly at the Active Inter-
face module, then observe the notes provided in the parameter descriptions.
Line droop control frequency droop no load frequency
A suitable value is obtained from the corresponding no load frequencies of the
other power generating units in the island grid as well as from the required load
distribution.
Line droop control frequency droop supplementary setpoint
In island grids with several power generating units, the no-load frequency is dy-
namically adapted to the instantaneous load and power generating conditions
using a higher level island grid control.
Grid droop control frequency droop gradient
A suitable value is obtained from the corresponding gradient values of the other
power generating units in the island grid as well as from the required load distri-
bution.
In the example, the following procedure provides a practical value to be set:
Measure the gradient of the diesel generator characteristic, and set p5407 to the
same value.
Line droop control frequency droop smoothing time
Other power generating units in the island grid must also manifest a frequency
droop, however they respond to load changes with a specific "inertia". In order to
avoid load peaks in individual power generating units for load steps in an island
grid, at least power generating units with similar power ratings must manifest a
comparable dynamic response. This dynamic response for active power changes
is set using p5409.
Line droop control additional frequency droop gradient
The additional droop offers a fundamental emulation of the dynamic speed dip or
overshoots of generators when load steps occur. Easing the output frequency as
a result of the additional droop avoids load peaks in the Active Line module, and
also helps dampen power oscillations in the island grid.
Grid droop control voltage droop no load voltage
1)
A suitable value is obtained from the corresponding no load voltages of the other
power generating units in the island grid as well as from the required load distri-
bution.
In the example, the following procedure provides a practical value to be set:
Measure the no load voltage of the diesel generator, and in test operation 2, set
the output voltage to the same value.
System Manual, 04/2015, A5E03347436A
Grid infeed