Upgrading Controls to
Maximize Performance,
Availability
Reprint from Combined Cycle Journal
2Q/2006
Author:
Bob Schwieger
Power Generation
Instrumentation & Controls
Upgrading controls to maximize
performance, availability
Editor’s note: Planned obsolescence is a
6B GTs to the same control system installed
vital component of almost every OEM’s
on its new 7FA addition. Drivers for this
(original equipment manufacturer)
decision included (1) increasing difficulty
business strategy—or so it seems.
in obtaining adequate service/parts for
Nowhere is this more evident than in the
the legacy systems, and (2) the need to
I&C sector where hardware and software
focus staff I&C technical resources on one
often are not supported by vendors beyond
platform to maximize both equipment and
about 10 years—unless a special long-
personnel performance.
term maintenance agreement is in force.
Generally speaking, owners want their
Clearly, there are many decades-old GTs
Web-based T3000’s simplified
powerplant controls to last forever. Most
still producing power for which a new
architecture, expanded capabilities
often, this is impractical thinking, given
controls system makes no economic sense.
benefit users
demanding duty cycles and operational
Most of these units either are relegated
goals; however, there are instances where
to peaker duty (operating a few hundred
band-aids make perfect sense.
hours per year at most) or are in baseload
the supply of powerplant control systems.
cogeneration service at industrial plants
It presented the following facts, among
The article that opens this section profiles
with marginally profitable product streams
others, at a recent industry forum: (1) 2700
the experience of two power producers
that cannot afford “new.”
I&C installations worldwide, (2) 700 GW
that are among the first to embrace
Siemens always has been able to support its
claim that the company is a global leader in
of installed capacity, (3) at the forefront
migration to Siemens’ new SPPA-T3000
Serving the legacy community are
of automation technology, (4) a solutions
controls for their gas turbines (GTs); one
small solutions providers with in-
provider with original process know-how.
installed it plant-wide. Both users had the
house troubleshooting and repair/
OEM’s TXP controls on their respective
refurbishment expertise. Companies
However, the OEM has not been nearly
501FD2 engines and wanted to take
that come to mind include Pond &
as successful in the US as it has been in
advantage of GT upgrades to improve
Lucier LLC (www. pondlucier.com) and
performance and profitability. The T3000
Process Control Solutions LLC (www.
facilitated this effort.
processcontrolsolutionsllc.com), which are
visible at many user-group meetings.
While it was possible, in both cases, to
other countries. One reason the controls
market here has been difficult for Siemens
is that it sold relatively few gas and steam
turbines (ST) in America before buying
Westinghouse Electric Corp’s fossil power
generation business unit eight years ago.
expand and enhance the existing controls
Such service organizations have access
systems to achieve operating goals,
to affordable replacement components
economics dictated a switch to the T3000.
made by the OEM and purchased new
An announcement by Siemens—rumored
on closeouts, or new or used parts from
for some time and made official early this
plants that have upgraded machines and
huge aftermarket services business receptive
year—that it would no longer support on
no longer need their original equipment or
to turbine/generator and controls upgrades.
a standard business basis TXP and earlier
the spares for it. Third-party alternatives
controls platforms made the decision
to OEM parts also may be available. Users
But that was not enough to ensure success;
relatively easy.
without access to a network of parts
the product had to be right. US powerplant
providers might start their search with a
owner/operators did not embrace the
Second article describes the experience
warehouse such as Gas Turbine Controls
of a major chemical/refining facility in
Corp (www.gasturbinecontrols.com).
upgrading three 1980s-vintage GE Frame
2
That acquisition, together with the purchase
of A-C [Allis Chalmers] Equipment Services
seven years earlier, gave the company a large
“installed base” and opened the door to a
Teleperm ME control systems installed
on the first GTs Siemens sold here in the
early 1990s. Operators questioned its
Thin clients
Thin clients
Operator terminals
Operation
Web
server
(Java)
1. Three-tier architecture of the Webbased T3000 (right) mirrors the structure
of the Internet and is less complex than a
traditional distributed control system (left).
Interconnection among all T3000 components
is achieved by a standard Ethernet network
with TCP/IP. Access to the process is provided
by Profibus DP field bus
Engineering
Historian
HMI
Diagnostics
Data
Engineering
Diagnostics
Built-in Web
server (Java/xml)
Archive
System SW
Embedded
Component
Services
Data
Alarm
Field
I/O modules
Spare parts
Spare parts
flexibility, technicians noted its difficulty
control-system software and test them prior
engineer, and output and forecasting
to troubleshoot and reprogram—at
to field implementation. If the changes
information for the production planner. It
least compared to traditional offerings.
prove problematic, the initial version of the
also informs the power broker about reserve
Operability and maintainability were
software can be restored. This approach is
load, the plant manager and operations
enhanced with the Windows-based Teleperm
not used in Europe.
personnel about plant status, etc.
shortcomings, according to at least some
The T3000 was first announced in June
Filtering out the relevant information to
users.
2005 as favorable test data and operating
meet the specific needs of each job function
experience rolled in from a couple of
improves productivity. In brief, the right
Next, the TCS7 debuted. It was promoted
beta sites. It was formally introduced for
information is made available to the right
as the user-friendly flexible and scalable
global commercial application by Speh last
people at the right time. One advantage
controls solution particularly well suited
December.
of his approach is that it enables fleetwide
XP (TXP) that followed. But it also had
administration, maintenance planning, etc,
for GT and ST retrofit applications in North
America. But the TCS7, it turns out, was an
System details
from a central location.
interim solution.
At that time, he elaborated on the simplicity
A lower total cost of ownership is an
Listening to customers. Siemens had
of the T3000’s architecture and on some of
advantage of the T3000 over a traditional
made the decision about five years ago to
the ways the system benefits users. Speh
distributed control system, claimed Speh.
develop a control system especially for the
said the new controls platform is supported
The DCS typically requires a wide range of
US and the national markets this country
by these three pillars:
software applications, as Fig 1 illustrates,
each demanding specific expertise for
influences—such as Australia. In a recent
presentation to the industry, Dr Rainer M
Three-tier architecture.
handling, updating, and maintenance.
Speh, CTO of Siemens Power Generation’s
Hardware design without subsystems.
The T3000 approach eliminates the need
Embedded component services.
for subsystems, thereby greatly simplifying
I&C Div, explained the differences in controls
philosophy between Europe and America.
European powerplant operators, he said,
system architecture. For example, the
The T3000 is completely Web-based and the
system’s application server is used for non-
three-tier architecture mirrors the structure
critical services—such as data archiving—
of the Internet, Speh noted (Fig 1). The
and the automation server to handle the
With object-oriented navigation, Speh
data tier is where process information is
real-time automation function. A benefit
continued, you activate, a “pump” or
received. Data processing is next, followed
of architectural simplicity: Any task can be
a “drive,” for example. Signal-oriented
by the presentation tier. Last consists of
accomplished at a single workstation. All
navigation, by contrast, relies on the “on”
standard browser-equipped data terminals.
information required is only a click away.
feedback from that pump or drive. He
The system is seamlessly integrated into the
assured the audience that while designing
customer’s IT landscape.
favor object-oriented navigation; those in
the US, signal-oriented navigation.
Use of Java and xml promises to simplify
adaptation of applications to possible
for either is not a problem in terms of
automation engineering, both require
Information is the key to success, Speh
future platforms. Java makes the T3000
completely different human/ machine
reminded attendees. While the T3000 makes
independent of the software and of the
interfaces (HMIs).
all the data it processes available throughout
operating system; xml is the solution
the enterprise, specific information can be
technology for data storage. The hierarchical
An example of another difference is the
accessed only by those authorized to have
file structure facilitates data exchange with
“rollback function.” In the US, owner/
it. For example, the processing tier compiles
other systems, such as the computerized
operators routinely make changes to
operational statistics for the maintenance
maintenance management system.
3
Success at High Desert
Integrated
engineering for
fast configuration
and modification
Andrew D Stevens, PE, O&M manager for
operations, explained to the editors of
the COMBINED CYCLE Journal during a
Information to facilitate
plant operation
plant visit that High Desert dispatches into
Operation
the competitive power market and that
high reliability is key to financial success.
Engineering
Diagnostics
Philosophy is to continually upgrade
Embedded
Component
Services
Diagnostics for optimizing
maintenance strategies
Archive
equipment to improve availability.
Alarm
Field
Trip reports, alarm
summary displays, and
event reports to facilitate
troubleshooting
Siemens’ decision to reduce its level of
support for the TXP controls originally
installed on the facility’s three GTs (see
editor’s note above) certainly is not
conducive to availability improvement.
In addition, the existing controls were
Secure lifetime archiving
Integrated process interface
for field-device communication
“maxed out” and High Desert couldn’t
take advantage of some desired product
modifications (ProdMods) without upgrading
2. T3000 allows users to call up, from a single workstation, diagnostics, engineering, operation,
and other screens (views). Information is accessed to the depth required; navigation among the
various views is simple and fast. Just a standard browser is required to view the status of the
entire plant and to perform all automation activities
the TXP. The plant had no issues with the
TXP, but simple economics dictated the
switch to T3000.
Siemens calls the heart of its new control
First T3000 installed on a commercial basis
Control systems for other major equipment
system— the software—Embedded
was at the TE-TO district heating plant
were not involved in the upgrade project:
Component Services ™. It is based on object
in Zagreb, Croatia, owned by Hrvatska
Toshiba International Corp’s steam turbine/
oriented data storage. All information
Elektroprivreda dd (HEP). Boiler and turbine
generator has the OEM’s standard offering,
associated with a component—such as a
controls were retrofitted on Unit 3 in
PLCs (programmable logic controllers)
pump—is complied in a single software
November 2003. General Manager A Rundek
operate water treatment equipment,
module. Benefit here is that pump data
is quoted as saying, “It’s flexible, it’s easy to
and BOP control is by Emerson Process
are processed only once and consistent
use and maintain, and fits our needs.”
Management s Ovation®.
Siemens also reports extremely high
Stevens explained that the T3000 upgrade
reliability with the first replacement of a
was scheduled as an add-on to a 24,000-hr
DCS in Germany by the T3000. That project
hot-gas-path overhaul, which by itself would
information is made available for operation,
engineering, alarming, etc (Fig 2).
Applications, experience
was for coal-fired Unit 7 at Rheinhafen
have had a nominal timeline of about three
The T3000 is designed to perform all
Dampf-Kraftwerk, owned by Energie Baden-
weeks. He added that the upgrade plan
powerplant automation tasks: turbine
Wuerttemberg AG (EnBW).
developed last fall relied on plant staff doing
control, boiler control, balance of plant
a significant part of the work with OEM
(BOP), and integration of third-party
Here in the US, the first two large
systems. Several dozen orders have been
combinedcycle projects to complete T3000
received by the OEM for both new and
upgrades are Constellation Energy Inc’s
retrofit applications involving turbine
High Desert Power Project and Seminole
and/or total plant control. Most are for
Electric Co-op Inc’s Payne Creek Generating
gas-turbine-based plants, but there are a
Station. The 830-MW 3 ° 1 High Desert plant
Last December there was a one-day project
couple of replacement control systems for
upgraded the control systems on its three
overview in the OEM’s Orlando facility.
coalfired units as well. Buyers include power
GTs as part of a wider plant improvement
Constellation personnel reviewed the
producers in the Americas, Europe, Asia, and
program while the 500-MW 2 ° 1 Payne
upgrade process, spent some time operating
the Middle East.
Creek replaced both GT and plant controls.
a T3000 mockup, and discussed with
4
oversight. To ensure excellent collaboration
between Siemens and Constellation
personnel, Stevens scheduled appropriate
training.
Siemens the plant’s requirements regarding
than a day. Field I/O (input/output) devices
screen arrangements. Goal was to keep the
were not disturbed.
new screens looking essentially like the old
The OTC upgrade package, which
required new field sensors to measure
exhaust temperature and barometric
Some technicians moved over to Unit 2 to
pressure. By way of background, OTC
do the same work just completed on Unit
(for outlet-temperature corrected) is a
In January, key personnel went to Siemens’
3 while others remained at Unit 3 to install
control process that manages operation
Alpharetta (Ga) facility for a one-week
software and begin system checkout tests.
in a closed loop to a corrected exhaust
general training program on the T3000.
One of the many things that had to be
temperature based on variations in
Plant-specific functionality was not included.
confirmed: Could the thin-client displays see
ambient conditions and engine speed.
A half-day session on how to navigate the
the necessary information from the I/Os?
ones to facilitate operations.
T3000 was conducted for all operations
personnel when Siemens was onsite to
At the end of the first week of nominal 12-hr
guide the upgrade project.
days, modifications to the three GT control
systems were complete, the HMI screens
O&M Techs Devin Quantz and Bryan Johnson
generally showed the information expected,
were deeply involved in the upgrade project,
and communications among the various
gaining the experience necessary to keep the
T3000 components were verified.
system operating reliably after Siemens left
the site. They outlined the following steps as
Some of the Siemens technical advisors
critical to the High Desert conversion, which
left High Desert before the beginning of
began the first week of February:
Week 2 when plant personnel started loop
checks to verify that the data received was
Step 1 (Day 1). Download data on
the information expected. Next, work was
operating starts and hours, as well as on gas
initiated on integrating the T3000 with
composition, from the TXP for uploading to
Ovation, which involved primarily the
the T3000 when installed.
transfer of information on the new turbine
controls to the existing BOP system.
Step 2 (Day 1). Decommission and
powerdown the TXP controls, field
During the loop checks, Quantz, Johnson,
processors, and HMI after turbine and
and their colleagues ran through several
lube-oil cool-down. Note that turning-gear
hundred “forced actions” to verify such
operation is monitored, but not controlled,
things as valves opening and closing when
by either the TXP or T3000.
they were supposed to. This activity was
particularly time-consuming at High Desert
Step 3 (Day 1). Begin gutting the existing
because ProdMods were being implemented
control cabinets.
in parallel with the controls retrofit and they
Siemens had a team of five onsite, and
with the help of plant personnel, removed
the Unit 3 TXP and installed the T3000—
including all rack-mounted processors and
equipment (computers, etc)—in little more
required additional loop checks as those
Compressor enhancements to improve
performance.
Addition of a BOP optimizer that helps
balance load among the three GTs.
Installation of General Physics Corp’s
EtaPRO product for performance
monitoring, modeling, problem
diagnosis, etc.
Quantz and Johnson said much of the work
just prior to commissioning had to do with
verifying screens and labeling—check and
re-check. An example they gave as typical
of a change: Lubeoil pump “on” should be
red; was gray. One of the actions that helped
to resolve several issues was upgrading of
signal quality from the I/Os.
Stevens said that the outage was planned
for 31 days—including commissioning of
the new controls and ProdMods. Quantz
and Johnson proudly related that the
controls work didn’t take all that time;
they completed their tasks ahead of the
mechanical work. Siemens did its part,
Stevens added, in meeting the schedule
established for its work.
upgrades were completed. They included,
for example:
Commissioning is a challenging activity for a
new control system. Reason is that you have
to accomplish it within established emissions
5
constraints. For new plants, there’s flexibility
Stevens made one observation that
Giddings suggested having adequate
on emissions during the commissioning
might be of concern at some plants:
onsite representation by the OEM during
phase, no so for an existing facility.
Information on the optical disks used to
commissioning to identify and solve
Minimizing emissions required that Siemens
archive operating data with TXP can’t be
problems quickly. During the Payne Creek
have its experts—particularly those with
readily transferred to the new system.
restart there were a half-dozen or more
in-depth knowledge of startup logic—on
So remnants of the TXP remain in the
Siemens troubleshooters at the plant. One
hand, as well as close coordination between
control room to access these data if
GT and the ST were recommissioned in four
OEM and plant personnel. Stevens stressed
need be.
days, the second GT in two.
that it wasn’t the T3000 that demanded
Payne Creek experience positive
Thinking about a controls upgrade?
Payne Creek’s T3000 upgrade was more
Among the more than three dozen GTs
To ensure that commissioning would
extensive than High Desert’s. Like the
already slated for T3000 upgrades over the
not exceed the five days allocated, plant
California plant, however, Payne Creek
next six to nine months or so, there are
operators simulated the startup logic to
required an increase in both control capacity
several projects that might help guide when
eliminate as many bugs as possible before
and functionality and opted for conversion
and how to replace the control systems at
going live. Quantz and Johnson said that
rather than expansion of the existing system.
your facility—that is, should you consider
they were surprised to find anomalies at this
Gary Giddings, O&M superintendent, said
the Siemens offering a viable alternative.
stage given all the verification before hand.
the T3000 installed just before mid-year
But they did.
performs turbine governor control functions
In particular, following the upgrades at
for the GTs and steam turbine (ST), plus
four power stations in Saudi Arabia and
Many controls-related issues identified
plant control functions for the heat recovery
Korea may help those operating equipment
during startup, they continued, had to do
steam generators. It also supervises auxiliary
installed more than 10 years ago that still
with communication between the T3000
control systems.
have the original control systems. The
special attention, rather it was total package
of upgrades.
COMBINED CYCLE Journal will publish
and Ovation; most were corrected with
relatively simple logic changes. Work
on the T3000 typically was related to
display cleanup. Operators were relatively
pleased, Stevens said, because the
screens had a familiar look and feel. Alarm
acknowledgement was one area that was
different, but it presented no difficulty.
Experience since the completion of
When the editors spoke with Giddings,
progress reports; an alternative is to attend
commissioning essentially was complete
user-group meetings—such as the W501D5/
and checkout on dual-fuel operation was
D5A— for details direct from owner/
about to begin. To that point, he said, the
operators.
project had gone smoothly. Any difficulties
encountered were addressed with relatively
Saudi Electricity Co will upgrade the
minor logic changes and tuning. Conversion
I&C systems on 16 GE Frame 7 and five
was done during a major overhaul with no
Westinghouse W501D GTs at its Shedgum
schedule impact.
and Faras plants. Total output from those
commissioning in March has been generally
Giddings sent eight technicians to Siemens
good:
for a week-long training program and
Operators have had few complaints.
There has not been a GT trip attributed
to a T3000 malfunction.
Quantz and Johnson say that a
significant benefit of the new control
they did virtually all the work required in
removing the TXP and installing the T3000;
technical oversight was provided by two
OEM engineers. Hardware installation took
five days after both the GTs and ST were cool
and off turning gear.
the original Mark II controls on the Frame 7s
and WDPF systems on the W501Ds.
Existing field devices will remain, except
where they are not compatible with the
new control systems. For example, vibration
instrumentation will be replaced on all
machines as will the automatic voltage
system is that it is easier to troubleshoot
Giddings attributed project success in large
regulators on the generator exciters. In
from one location than TXP. Both
part to the training program, as well as to
some cases, fuel-system instrumentation
technicians say they continue to deal
careful review of hardware in the factory.
and control valves will be replaced on the
with display-related issues and they are
The latter benefited both the vendor and
W501Ds.
resolved one at a time.
utility, he said, because inspection revealed
the need for a few changes that were made
prior to shipment.
6
facilities is 1650 MW. The T3000 will replace
3. WDPF at left is relatively easy to upgrade to
the T3000 (right). Essentially, the original “A”
cabinet goes away and the T3000 installed in
the original footprint. Field devices terminate
in the “B” cabinet and, via special connector,
mate up with the I/O cards in the “A” cabinet.
Original field terminals and cables remain in
place, loop checks confirm software functions
120
V dc
120
V dc
“B” cabinet “A” cabinet
terminations with DPU
and I/O
“B” cabinet New T3000
terminations controls
with I/O
Install T3000 cabinet with new
East-West Power Co’s Ilsan Power Plant,
processors and I/O modules.
located just outside Seoul in South Korea,
will begin converting its six W501D5
Connect new I/O via the existing WDPF
engines from WDPF to T3000 in August.
plug.
The machines are arranged in combined-
Install new application software for
cycle power blocks of 4 ° 1 and 2 ° 1 that
processors.
produce a total of 830 MW. This work will be
Install new operator stations.
conducted in three phases and completed
by fall 2007. One reason for the controls
Most plants choose to do their own
upgrade is to support the installation of
installation work, Hitzel continues, and rely
advanced dry low-NOx (DLN) systems on all
on Siemens for onsite technical advisors. It
engines.
takes about six months, he says, to plan and
order the hardware for a typical upgrade.
A similar project is underway at GS Power
Co’s 473-MW Buchon Power Plant where
What’s involved, what does it cost?
three W501D5s will convert from WDPF
Regarding cost for replacing the WDPF on
one GT with T3000, he offers the following
as a guide for preliminary budgeting:
to T3000 with the combustor dynamics
Ron Hitzel, Siemens’ global I&C marketing
protection system option. The CDPS is a step
integration manager, offers some general
up from the more common CDMS, which
comments on what plants should consider
monitors engine pressure fluctuations.
control upgrades and on the costs involved.
Former is connected directly to the T3000
By way of background, he said that the WDPF
to tune the DLN system. One of its functions
was the turbine control system installed
about 3.5X if customer provides labor;
is pilot-gas modulation to ensure flame
on Westinghouse GTs from the mid 1980s
about 4X if Siemens uses its technicians.
stability and tightly control emissions. Note
to 2001. The 8 Level system, he continued
Dual-fuel engines are slightly more
that both Ilsan and Buchon operate primarily
is the only WDPF still “active” for OEM
expensive to upgrade; figure about 4.5X
on liquefied natural gas. Backup fuel is
support; however, it may not accommodate
for a 501F with the owner doing the
distillate oil.
the implementation of certain Prod- Mods
installation.
that owners would consider for plant
AES Corp’s Uruguaiana Power Plant, a
improvement.
600- MW, 2 ° 1 combined cycle near the
Add capacity to the existing WDPF,
about $100,000 (X).
Replace existing WDPF with T3000,
Upgrading the company’s TCS7 to
T3000 is somewhat easier, Hitzel says.
Software changes and installation of
Argentina border, also will convert to the
Conversion from WDPF to the T3000
T3000 and install a CDPS. Major difference
is relatively simple, Hitzel assures. He
between the projects is that Uruguaiana’s
recommends this implementation strategy
GTs are W501FCs.
(Fig 3):
Reuse the existing I/O cabinet. Field
devices generally are fine, Hitzel says,
a fault-tolerant server (the application
server) is all that’s usually required;
hardware is the same. Driver for this
conversion generally is a desire to have
all equipment on one controls platform.
ccj
and often require no special work.
7
This article appeared in:
Combined Cycle Journal, pages 111 - 118
2Q/2006
Copyright © 2006 by
PSI Media Inc
This reprint is published by:
Siemens AG
Power Generation
Freyeslebenstraße 1
91058 Erlangen, Germany
Siemens Power Generation, Inc.
Instrumentation & Controls
1345 Ridgeland Parkway, Suite 116
Alpharetta, GA 30004, USA
e-mail: sppa-t3000.pg@siemens.com
www.siemens.com/powergeneration
Order No. A96001-S90-A565-X-4A00
Printed in USA
1342 1107541B SD 11061.5
All rights reserved.
Subject to change without prior notice.
Trademarks mentioned in this document are
the property of Siemens AG, its affiliates, or
their respective owners.
The information in this document contains
general descriptions of the technical options
available which do not always have to be
present in individual cases. The required features
should therefore be specified in each individual
case at the time of closing the contract.
siemens.com/powergeneration