Commissioning Of Dynamic Grid Support; Commissioning The Anti-Islanding Function; Commissioning Voltage-Time Monitoring - Siemens SINAMICS S120 System Manual

7.8

Commissioning of dynamic grid support

For commissioning the dynamic grid support, reference is made to Chapter Commissioning
example of an infeed with dynamic grid support for a power grid (Page 86) and the general
function chapter (Function module, dynamic grid support (Page 40)).
7.8.1

Commissioning the anti-islanding function

Anti-islanding function is activated by setting parameter p5541 and configuration with
p5540.1. The setting of the permissible limit values for frequency and voltage is realized
using p5543 and p5544. If the limit values are exceeded, then this is signaled in status word
r5542. If the limit values are still exceeded during the wait time p5545[0], then fault F6851 is
output.
7.8.2

Commissioning voltage-time monitoring

Activating
The voltage-time monitoring is activated using p5540.4 = 1. The simple threshold monitoring
that is otherwise active is deactivated using p5543.
Response when grid faults occur
● The start of a grid fault is identified as soon as one phase of the grid voltage lies above
the threshold p5550[0] or below threshold p5550[1].
● The grid fault has ended as soon as all phases of the grid voltage lie below threshold
(p5550[0] - p5550[2]) or above threshold (p5550[1] + p5550[2]).
● Both voltage characteristics are monitored during a grid fault.
– When the HVRT curve is exceeded (voltage increases), then the system is shut down
– When the LVRT curve is fallen below (voltage dip), then the system is shut down
● If the grid voltage does not return within the parameterized fault duration p5551[9] or
p5553[9], then the system is shut down and fault F6851 is output. Taking into account the
selected hysteresis p5550[2], the lower limit of the tolerance range is (p5550[0] -
p5550[2]), the upper threshold is obtained according to the sum p5550[1] + p5550[2].
Grid infeed
System Manual, 04/2015, A5E03347436A
without delay and fault F6851 is output.
without delay and fault F6851 is output.
In the case of p5540.5 = 1, the shutdown is only realized after delay time p5545[2] has
expired.
This means that other brief voltage dips can, where necessary, be tolerated when the
grid returns.
7.8 Commissioning of dynamic grid support
Commissioning
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