Load-Side Components And Cables; Motor Reactor; Dv/Dt Filter Plus Vpl; Sine-Wave Filter - Siemens SINAMICS G130 Engineering Manual

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Load-side components and cables

Motor reactor

The fast switching of the IGBTs in the inverter causes high voltage rate of rise dv/dt at the inverter output. If long
motor cables are used, these voltage gradients increase the current load on the converter output due to capacitive
charge/discharge currents. The length of cable which may be connected is therefore limited.
The high voltage rate of rise and the resulting voltage spikes at the motor terminals, increase the voltage stress at the
motor winding in comparison to direct line operation. In conjunction with the connected cable capacitances, the motor
reactors reduce the capacitive charge/discharge currents in the motor cables and, as a function of the motor cable
length, limit the voltage rate of rise dv/dt and the voltage spikes V
For a more detailed description, please refer to the section "Motor reactors" of the chapter "Fundamental Principles
and System Description".

dv/dt filter plus VPL

The dv/dt filter plus VPL consists of two components, the dv/dt reactor and the voltage limiting network (Voltage Peak
Limiter), which limits voltage spikes and returns the energy back to the DC link.
The dv/dt filter plus VPL must be used for motors for which the withstand voltage of the insulation system is unknown
or insufficient. Motors in the 1LA and 1LG ranges require this type of filter only when they are connected to a supply
voltage exceeding 500 V +10 % and no special insulation is used on the motor.
The dv/dt filter plus VPL limits the voltage rate of rise to values < 500 V/µs and the typical voltage spikes at the motor
to the values below:
•
V (typically) < 1000 V
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•
V (typically) < 1250 V
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For a more detailed description, please refer to the section "dv/dt filters plus VPL" of the chapter "Fundamental
Principles and System Description".

Sine-wave filter

Sine-wave filters are LC low-pass filters and constitute the most sophisticated filter solution. They are significantly
more effective than dv/dt filters plus VPL in reducing the voltage rate of rise dv/dt and peak voltages V
operation with sine-wave filters imposes substantial restrictions in terms of the possible pulse frequency settings and
voltage and current utilization of the motor-side inverter (voltage and current derating).
For a more detailed description and for the derating data, please refer to the section "Sine-wave filters" of the chapter
"Fundamental Principles and System Description".

Maximum connectable motor cable lengths

The table shows the maximum connectable motor cable lengths. The values apply to the motor cable types
recommended in the table as well as to other types of cable.
Line supply voltage Output power at
400 V / 500 V / 690 V
Without reactor or filter
380 V – 480 V 3AC
500 V – 600 V 3AC
660 V – 690 V 3AC
With one motor reactor
380 V – 480 V 3AC
500 V – 600 V 3AC
660 V – 690 V 3AC
Permissible motor cable lengths for SINAMICS G130
for V
Line
for 660 V < V
Line
e.g. Protodur NYCWY
110 kW - 560 kW
110 kW - 560 kW
75 kW - 800 kW
110 kW - 560 kW
110 kW - 560 kW
75 kW - 800 kW
at the motor terminals.
PP
< 575 V
< 690 V
Maximum permissible motor cable length
Shielded cable
300 m
300 m
300 m
300 m
300 m
300 m
SINAMICS Engineering Manual - May 2008
SINAMICS G130
Engineering Information
Unshielded cable
e.g. Protodur NYY
450 m
450 m
450 m
450 m
450 m
450 m
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© Siemens AG
, but
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