Siemens SINAMICS G130 Engineering Manual page 164

General Engineering Information for SINAMICS
Engineering Information
Replacement of SIMOVERT P converters by SINAMICS
As SIMOVERT P converters and SINAMICS converters are both designed as voltage-source, DC link converters and
the matching motors feature relatively high-leakage models of rotor, it is generally easy to replace a SIMOVERT P
with a SINAMICS unit. However, the following aspects need to be taken into account:
•
SIMOVERT P converters are existing as a standard version for 1Q operation and as an NGP version for
4Q operation (line-side converter for rectifier/regenerative operation). This must be taken into account to
ensure correct selection of the SINAMICS unit for 1Q or 4Q operation.
•
For the output power range of 1LA1 motors typically parallel connections of converters are used.
However, 1LA1 motors for operation on SIMOVERT P converters do not have electrically isolated winding
systems and this must be taken into account in the selection of the appropriate parallel connections of
SINAMICS converters. For further details, e.g. minimum cable lengths to the motor or maximum attainable
output voltage without pulse-edge modulation, please refer to the section "Parallel connections of
converters" of the chapter "Fundamental Principles and System Description".
•
SIMOVERT P converters operate on lower pulse frequencies than the newer SINAMICS devices. When a
SIMOVERT P unit is replaced by a SINAMICS, therefore, the stray losses in the motor and the motor
noise caused by the converter supply are slightly lower.
It is also important to note the potential problems affecting the motors:
•
Voltage stress on the motor winding
•
Bearing currents in the motor bearings.
Solutions to counter these problems are available. For example, motor reactors or motor filters can be installed at the
SINAMICS converter output, or the motor can be retrofitted with an insulated bearing in an approved service
workshop.
1. Measures recommended when replacing a 6SE35/36 transistorized frequency converter for a line supply voltage of
≤ 500 V
1.1 Operation with 1LA6 motors:
•
Use a motor reactor on the SINAMICS converter to reduce the voltage rate of rise dv/dt and retrofit an
insulated bearing to the non-drive end of the motor
or
•
Use a dv/dt filter plus VPL on the SINAMICS converter, but do not modify the motor
1.2 Operation with 1LA1 motors:
•
No measures required
2. Measures recommended when replacing a 6SC36/37 GTO converter for a line supply voltage of 600 V to 690 V
2.1 Operation with 1LA6 motors:
•
Use a dv/dt filter plus VPL on the SINAMICS converter, but do not modify the motor
2.2 Operation with 1LA1 motors:
•
No measures required
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Notice! If the motor is retrofitted with an insulated non-drive end bearing and also has a speed encoder, the
encoder must also be insulated or replaced by an encoder with insulated bearings.
SINAMICS Engineering Manual – May 2008
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© Siemens AG
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