More power reliably into the grid
thanks to adapted electrical systems
at Niederaussem
Electrical Solutions Reference
Instrumentation, Controls & Electrical
SPPA-E3000 Power Upgrade Package
optimally aids to adapt the electrical
components and systems during the turbine
upgrade at the Niederaussem power plant.
The Plant
The first unit of a new lignite-fired base-load
power plant went into operation in 1963 at the
RWE Power AG site in Niederaussem. The plant
has undergone continual expansion ever since.
It currently comprises nine units and with a total
net capacity of 3680 MW it is one of the largest
lignite-fired power plants in Europe.
The Result
■ Reliable transmission of the
increased power into the
grid
■ High planning and
scheduling reliability thanks
to trouble-free project
execution with Siemens as
the central partner
protection made the medium-voltage system
to be able to cope with the extended lifetime.
The entire MV protection system was replaced
and integrated in the new I&C via IEC 61850.
This direct integration of the electrical
components into SPPA-T3000 produces a
uniform and innovative operation and
monitoring system with increased diagnostic
and analysis capabilities.
With Siemens as a central partner for all the
issues relating to modernization of the electrical
systems, it was possible to complete the on-site
changeout, including dismantling, installation
and commissioning, in only 10 weeks.
The Task
The "MOD 600" retrofit program for lifetime
extension and for more profitable operation of
the two 600-MW units G and H at the
Niederaussem power plant also included the
uprating of the turbine. To cope with this
increased power output, the electrical systems
in the plant had to be adapted.
Our Solution
An I&C modernization based on SPPA-T3000
and an uprating of the LP turbine were required
in order to achieve the objectives of the retrofit
program. As far as the necessary modernization
of electrical systems was concerned, Siemens
had the competitive edge over the competitors
in all the sub-packages of the contract.
Price, competence and a comprehensive and
economically sound solution won us the tender.
The turnkey SPPA-E3000 Power Upgrade
Package, which is customized for use with each
individual plant, included an upgrade of the
generator bus ducting to enable the increased
generator current to be reliably transferred to the
grid. The LV switchgear was also replaced while
using the existing power and control cables.
Modernization of the unit auxiliary supply
“We are totally satisfied both
with the result and with the
execution of the electrical
project. The close cooperation
between our personnel and the
on-site Siemens project team
made it possible to adhere to
the tight time schedule and the
equally tight budget.”
Tilman Bechthold
Power Plant Manager at Niederaussem
RWE Power AG
Answers for energy.
Retrofit of generator bus ducting
A core component of the overall project
was the uprating of the turbine.
The generator had the necessary reserves,
but the bus ducting had come up against
its performance limits. This was confirmed
by thermographic testing of the generator
bus ducting.
For this reason RWE opted for complete
servicing and modernization of the
generator bus ducting. Silver-plated
flexible connectors were installed in the
generator connection to reduce losses.
Because the existing current transformers
were no longer able to accurately convert
the increased current subsequent to the
uprating, they were replaced with transformers with a higher primary current. The
voltage transformers were also replaced,
as these were close to the end of their
service life.
New insulators and seals were fitted
throughout, in addition to a number of
other internal components.
Connection of generator bus ducting
Replacement of low-voltage switchgear
The low-voltage switchgear no longer
satisfied current standards and was also
replaced as part of the project.
The new switchgear with a total of 150
panels and over 1000 load feeders had
to be reinstalled in the same place.
Extensive preparatory measures, both at
the Siemens factory and on site, were
necessary in order to reliably complete
the work within the scheduled changeout
time. The new switchgear was assembled
at the factory in a full-scale simulation
and tested prior to acceptance by the
customer. This included wiring of the
cross-panel inter-locks, connection of the
automatic transfer gear and assembly of
the I&C equipment.
All the interlocks and automatic transfer
gear and the interaction with the I&C were
tested bit for bit in this configuration.
The switchgear panels were then
delivered directly to Niederaussem for
installation and connection. This ensured
that commissioning could be carried out in
the shortest possible time.
SIVACON encapsulated low-voltage
switchgear
Retrofit for medium-voltage switchgear
and integration in the process I&C based
on IEC 61850
The upcoming inspection and overhaul of
the switchgear panels and circuit breakers
in the medium-voltage switchgear was
performed in the course of the project.
However, the replacement of the
protection system was the main focus of
the medium-voltage retrofit. Protection
devices from the Siemens SIPROTEC family
were used. These devices are equipped
with IEC 61850 interfaces and could
therefore be integrated directly in
SPPA-T3000 without the need for any
further modification.
Further information from the unit auxiliary
supply systems, e. g. the low-voltage
switchgear, the automatic transfer gear
and many other components, was
acquired using system components from
the SICAM 1703 range and transferred to
the I&C by means of an Ethernet link and
IEC 61850.
The direct integration of the electrical
components in the process I&C permits
extensive analysis in the event of a fault.
When SIPROTEC devices are used, this is
further enhanced by a time resolution of
1 ms and, more importantly, by a high
time accuracy of < 1 ms between the
individual field devices.
Published by and copyright © 2012:
Siemens AG, Energy Sector
Freyeslebenstrasse 1
91058 Erlangen, Germany
E304_FR_PUP_Niederaussem_e_V2-0
Order no. E50001-G230-A284-X-4A00
For more information contact
sppa-e3000.energy@siemens.com
www.siemens.com/energy/sppa-e3000
Siemens AG
Fossil Power Generation
Instrumentation, Controls & Electrical
Siemensallee 84
76187 Karlsruhe, Germany
Printed in Germany
Dispo 05401, c4bs-Nr. 7465
Printed on elementary chlorine-free
bleached paper.
Extract from an overview diagram from
SPPA-T3000
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the property of Siemens AG, its affiliates, or
their respective owners.
Subject to change without prior notice.
The information in this document contains
general descriptions of the technical options
available, which may not apply in all cases.
The required technical options should therefore
be specified in the contract.