Siemens SINAMICS S120 System Manual page 41

Example of a characteristic curve for dynamic grid support in accordance with German
BDEW Guidelines for connection to medium-voltage grids
Figure 5-4
Explanations for voltage control:
● Voltage deadband:
In the range between 0.9 x U
support.
● The rise time is < 20 ms (typical ∼10 ms).
● Voltage control after returning to the voltage deadband is maintained for a further 500 ms
(p5507[0], parameterizable).
● Reactive current: I
● The default setting of the characteristic curve parameter corresponds to the characteristic
in accordance with the previous diagram.
● The magnitude and symmetry of the active and reactive current can be defined during a
fault ride through. This means that adaptations can be made to address grid codes as
well as special applications.
ΔI
B
ΔU = U - U
k:
U :
n
U :
0
U:
Grid infeed
System Manual, 04/2015, A5E03347436A
Dynamic grid support with voltage control in accordance with German BDEW Guidelines
= k x ((U - U
B
= I - I
B B0
0
Gradient of the characteristic
Rated voltage
Voltage before the fault
Instantaneous voltage
(during the fault)
5.3 Description of the function modules
≤ 1.1 x U , there is no requirement for dynamic grid
n n
)/U ) x I
0 n n
I : Rated current
n
I : Reactive current before the fault
B0
I : Reactive current
B
Function modules
41