Siemens SINAMICS S120 System Manual page 103

pulse inhibit for the ALM). After the debounce time has elapsed, then controlled ALM
operation is automatically assumed.
Note
If, already in the synchronous state, the application requires a long wait time for the circuit
breaker to close, then the feedback signal of the switch can be used for the enable
p5483.
Parameter r0863.1 (control external line contactor) is used as output to control the circuit
breaker. If the function "Grid transformer" is activated (magnetization mode p5480 > 0), the
command to close is issued via r0863.1 after the expiry of the premagnetizing ramp and
when synchronization is achieved.
Identification of the transformer data
The correct compensation of the voltage drop at the transformer and the optimum control of
the voltage at the grid connection point of the island grid by the Active Line Module requires
that the magnetizing inductance, leakage inductance and the phase shift of the transformer
are taken into account. This transformer-specific data is either provided by the transformer
manufacturer, and must be manually entered in the adjusting parameters of the expert list of
the Active Line Module of the island grid, or determined using the following measuring
routines in the sequence described below.
In the following, the DC link capacitance and, in the case of a connection to a power grid, the
grid inductance are identified.
Please note, to measure the phase shift, the leakage inductance and the grid inductance of
the connection to the power grid with closed circuit breaker must be known. To manually
change the parameters described in the following, using parameter p0010 (infeed
commissioning), "quick commissioning" must be selected; whereby this parameter must then
be set back to a value of 0 ("Ready").
Circuits and vector groups
The circuit configurations of three-phase transformers are the connections of the winding
phases of the input or output side to create star, delta or zigzag connections.
These circuit diagrams and the corresponding vector diagrams are shown in the following
diagram. The vector group specifies the connection of the phases of two windings of a
transformer, as well as the characteristic number for the phase position of the voltage vector.
These connection types are identified by the letters specified below:
● Star connection: Y, y
● Delta connection: D, d
● Zigzag connection: Z, z
The uppercase letters designate the connection of the primary winding; the lower case
letters, the secondary winding. The upper case letters come first in the vector groups. If the
neutral point of a winding is brought out into a star or zigzag connection, then the marking is
YN or ZN – or, yn or zn.
Grid infeed
System Manual, 04/2015, A5E03347436A
7.6 Commissioning the grid transformer
Commissioning
103