Siemens SINAMICS S120 System Manual page 126

Commissioning
7.8 Commissioning of dynamic grid support
Example for frequency-time monitoring
In the following example, the parameterization of a monitoring characteristic is shown for the
grid frequency according to the following diagram.
The individual characteristics required depend on the country-specific grid codes and the
specifications of the individual power utility company:
● A grid fault involving a frequency increase (HFRT) should be detected as soon as the
frequency exceeds the threshold of p5555[0] = 0.5 Hz.
● A grid fault involving a frequency decrease (LFRT) should be detected as soon as the
frequency exceeds the threshold of p5555[1] = -0.7 Hz.
● After the start of a grid fault, the frequency characteristics should be monitored as shown
in the following diagram.
● The system is immediately shut down when the upper curve is exceeded or the lower
curve is fallen below.
Figure 7-9
The settings for the frequency-time monitoring are described in the following table.
Table 7- 17
Times in s
Frequency increase (HFRT)
p5556[0] = 0.00
p5556[1] = 0.50
p5556[2] = 0.50
p5556[3] = 1.00
p5556[4] = 1.00
p5556[5] = 2.20
p5556[6] = 2.20
p5556[7] = 2.98
p5556[8] = 2.99
p5556[9] = 3.00
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Example for frequency-time monitoring
Settings for the frequency monitoring characteristics
Frequency values in Hz
p5557[0] = 0.6
p5557[1] = 0.6
p5557[2] = 0.5
p5557[3] = 0.5
p5557[4] = 0.4
p5557[5] = 0.4
p5557[6] = 0.3
p5557[7] = 0.3
p5557[8] = 0.3
p5557[9] = 0.3
System Manual, 04/2015, A5E03347436A
Grid infeed