Precharging Of The Dc Link And Precharging Currents; Basic Infeed - Siemens SINAMICS G130 Engineering Manual

6.5 Precharging of the DC link and precharging currents

6.5.1

Basic Infeed

Basic Line Modules with thyristors
In the case of SINAMICS S120 thyristor-based Basic Line Modules in frame sizes FB, FBL, GB and GBL, which are
available as S120 Chassis (air-cooled and liquid-cooled) and S120 Cabinet Modules, the DC link is precharged by
varying the firing angle of the rectifier thyristors (phase angle control). The firing angle is increased continuously for 1
second until it reaches the full firing angle setting. These modules do not feature a separate precharging circuit.
SINAMICS S120 thyristor-based Basic Line Modules: Precharging by phase angle control of the thyristor firing angle
The following table specifies the rms values of the line currents which occur at the beginning of the precharging
process in the case of line supply voltages 400 V or 690 V. These values are based on the assumption that the
maximum possible DC link capacitance must be precharged. The maximum possible capacitance values for the
relevant Basic Line Modules can be found in the next section. Where other line voltage values and / or other DC link
capacitance values apply, the precharging current values must be converted in proportion to the line voltage and / or
DC link capacitance.
The specified precharging currents decay during precharging until the process is completed after a period of typically
1 to 2 s. The precharging principle based on phase angle control means that precharging is a virtually loss-free
process which means that there are no mandatory minimum intervals between precharging operations (in contrast to
resistor-based precharging circuits).
S120 BLM output
at 400 V or 690 V
Frame size Output
380 V – 480 V 3AC
FB 200 kW
FB 250 kW
FBL 360 kW
FB 400 kW
GB 560 kW
FBL 600 kW
GB 710 kW
GBL 830 kW
500 V – 690 V 3AC
FB 250 kW
FB / FBL 355 kW
FB 560 kW
FBL 630 kW
GB 900 kW
GB / GBL 1100 kW
GBL 1370 kW
S120 thyristor-based Basic Line Modules: Line currents at the beginning of precharging (initial rms values)
Input current Precharging
at 400 V or 690 V
365 A Phasenanschnitt
460 A Phasenanschnitt
610 A Phase angle control
710 A Phasenanschnitt
1010 A Phasenanschnitt
1000 A Phase angle control
1265 A Phasenanschnitt
1420 A Phase angle control
260 A Phasenanschnitt
375 A / 340 A Phase angle control
575 A Phasenanschnitt
600 A Phase angle control
925 A Phasenanschnitt
1180 A / 1070 A Phase angle control
1350 A Phase angle control
Line current at the beginning of DC link
principle precharging (initial rms value)
SINAMICS Engineering Manual – November 2015
SINAMICS S120
Engineering Information
at 400 V or 690 V
146 A
184 A
244 A
284 A
404 A
400 A
506 A
568 A
130 A
188 A
288 A
300 A
463 A
590 A
675 A
357/528
Ó Siemens AG