Some Aspects of Digital I

1
International Conference, Bled, Slovenia, 5-8
September 2005 Nuclear Energy for New Europe 2005
Some Aspects of Digital IC and Digital
Human-System Interface (HSI) Upgrades in Nuclear
Power Plants Proposal for the MCR/MCB HSI
Endpoint Vision and the Migration Path
for NUCLEAR POWER PLANT KRKO - NEK
Damir Mandic Nuclear Power Plant Krko - NEK,
Slovenia (Conference paper No. 001)
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Some Aspects of Digital IC and Digital
Human-System Interface (HSI) Upgrades in Nuclear
Power Plants
The Conference Paper Content

• 1. Introduction
• 2. Migration from the original NEK design to the
  AS-BUILT 2005
• 2.1 The original NEK MCR/MCB HSI design
• 2.2 Migration from the original MCR/MCB HSI
  design to the 2005 AS-BUILT
• 2.3 Common basic characteristics of all HSI
  upgrades up to the 2005 AS-BUILT
• 3. IC upgrades and MCR modernization planning
• Management Considerations
• MCR/MCB Endpoint Definition
• Migration Strategy
• Human Factors Program Planning
• Planning for Regulatory and Licensing Activities
• 4. NEK MCR/MCB Endpoint Vision and Migration Path
• 4.1 NEK MCR/MCB Endpoint Vision
• 4.2 NEK Migration Path to the MCR/MCB Endpoint
  Vision
• 5. Risks of Implementing NPP MCR/MCB Digital HSI
  Upgrades
• 6. Conclusion

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INTRODUCTION
The current focus of all operating NPPs is SAFE
OPERATION ECONOMIC SURVIVAL. While producing
electricity in a productive and efficient manner,
operating NPPs strictly follow safety and
reliability requirements. In order to continue
meeting safety and reliability requirements and
at the same time to optimize nuclear power plant
operating costs, NPP licensees must be able to
replace and upgrade equipment in a cost effective
manner using approaches that reduce licensing and
technology risks. In-depth upgrade planning
ensures such approach. In the last thirty years
no other NPP technology has passed through so
spectacular development process as programmable
digital upgrades of Instrumentation and Control
(IC) systems and HSI (Human System Interface). A
design of a new plant and a new main control room
is not so challenging from the HSI point of view
as a modernization of the existing MCR in the
operating NPP. This presentation shall deal with
planning aspects of digital IC and HSI upgrades
in NPPs.
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PRESENTATION GOALS

• Rather than establishing the repetitive summary
  of facts already presented by the paper, the
  presentation shall utilize advantages of visual
  communication in order to
• Remind what is so special in digital IC
  upgrades.
• Explain objectives of the up-front planning
  efforts for IC upgrades and MCR modernization.
• Identify disadvantages (if any) and benefits for
  the early planning of the IC upgrades and MCR
  modernization.
• Visualize NEK MCR/MCB HSI migration 1978-2005.
• Visualize MCR/MCB HSI solutions of some other
  operating NPPs and plans for some future NPPs.
• Provide proposal for NEK MCR/MCB endpoint vision,
  migration path and short term plan for NEK.

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WHY DO WE SPEAK ABOUT SPECIFICS OF DIGITAL IC
USAGE IN NPP?
There is more than one answer !

• Because in any significant or larger project
  and/or investment we cannot void implementation
  of the programmable digital IC systems and
  software development. We always start to think
  "digital" when we speak about
• Equipment/Component obsolescence
• Increasing maintenance costs with old systems
• Reliability of old systems
• Limited upgrade/expansion options of old systems
• More effective HSI (Human System Interface) that
  is easier to use and flexible in application
• Enhancement of IC system functionality and
  performance (Digital IC systems have no drift,
  better accuracy, increased computational
  capabilities, remote data transfer capabilities,
  increased data storage capabilities)

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WHY DO WE SPEAK ABOUT SPECIFICS OF DIGITAL IC
USAGE IN NPP? (...CONTINUED)
There are few more answers !

• Because the current focus of all operating NPPs
  is
• Safe Operation Economic Survival, they all
  speak about
• Use of approaches that reduce licensing
  requirements and technology risks (sophisticated
  digital IC and HSI,
• ITS - Important To Safety Information Systems,
• COSS - Computerized Operator Support Software,
  Equipment Condition Monitoring)
• Reduction in staff and capital budgets
• Emphasis on cost-effective decisions
• Maintain versus modernize
• Various levels of modernization
• Replacement versus upgrade
• System versus component upgrade
• Greater use of off-the-shelf, rather than custom
  equipment

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WHY DO WE SPEAK ABOUT SPECIFICS OF DIGITAL IC
USAGE IN NPP? (...CONTINUED)
There is the last set of answers !

• Because programmable digital systems introduce
  new functionality and new advantages!

• Because programmable digital systems introduce
  new specific issues and new problems to be solved!

• Because regulatory standpoint regarding usage of
  programmable digital systems in Safety Systems of
  NPP has been clarified very late!

• Because problem solving approach in different
  plants and at different vendors is still not
  consistent and it is still beating its track.

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Objectives of the up-front planning effort for
IC Upgrades and MCR Modernization (EPRI 1008122)

• Define key operational, economic and human
  performance objectives and ground rules for the
  modernization, consistent with the overall goals
  of plant Management. Planning should ensure
  (that)
• Changes fit the Operations groups overall
  concept of operation.
• Changes fit a common vision for the MCR and plant
  operation.
• Licensing risk is minimized.
• Each of the steps taken to achieve modernization
  is consistent with the resources available.
• Consistency and Integration of the modifications
  that may be made over many years.
• Existing human factors/human performance problems
  are addressed and resolved by modifications.
• (continued on next slide...)

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Objectives of the up-front planning effort for
IC Upgrades and MCR Modernization (...CONTINUED)
Planning should ensure (that)

• Completion of HFE planning process definition
  once up-front, consistent with good practice and
  regulatory body expectations, and then use and
  re-use this as each modification is made.
• Definition of graded approach to application of
  HFE.
• HSI improvement through appropriate use of
  technology.
• Hybrid HSI is adequately addressed within the
  migration strategy.
• Interim configurations along the migration path
  meet the regulatory requirements and are
  self-consistent (can stay as they are in interim
  configuration as long as needed).
• Changes to the simulator, training and operator
  procedures are properly addressed.

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ARGUMENTS THAT COULD BE HEARD AGAINST EARLY,
UP-FRONT PLANNING EFFORTS FOR DIGITAL IC
UPGRADES AND MCR MODERNIZATION

• (Digital IC Upgrades and MCR Modernization
  projects in
• an operating NPP are referred to as UPGRADE on
  this slide)
• UPGRADE is challenging task associated with many
  risks.
• UPGRADE usually lasts very long (10-15 years
  minimum).
• UPGRADE is very expensive, in early planning
  phase cost is unknown.
• If not implemented correctly, UPGRADE could have
  negative impact on plant availability,
  productivity, reliability, and plant safety.
• Not so many successful operating references for
  an UPGRADE.
• NPPs that operate more than 25 years are facing
  serious problems with personnel turnover. Mandate
  of the existing human resources (on all levels,
  from team members to the management) involved in
  UPGRADE is several times shorter than the project
  duration.
• There are not so many vendors on the world
  digital IC market with consistent, integrated
  solutions that include qualified IC platform and
  long-term compatibility commitments. The
  situation shall not improve before opening of a
  new NPP construction cycle in the U.S.A.

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GOOD NEWS ABOUT EARLY, UP-FRONT PLANNING
EFFORTS FOR DIGITAL IC UPGRADES AND MCR
MODERNIZATION

• (Digital IC Upgrades and MCR Modernization
  projects in
• an operating NPP are referred to as UPGRADE on
  this slide)
• The first two steps of UPGRADE planning
  (definition of the MCR Endpoint Vision and the
  Migration Path) cost almost nothing (several
  man/months).
• Planning efforts (MCR Endpoint Vision, Migration
  Path, HFE Program) ensure guidance and
  consistency for all future modifications thus
  minimizing possible reworks during the migration
  path, until full UPGRADE is implemented.
• Outputs of UPGRADE planning can be revised when
  and if needed, ensuring compliance of the revised
  planning outputs with AS-BUILT status of the
  plant.
• Up-front planning efforts for UPGRADE do not
  require commitment to any long term budget
  resources as a prerequisite.
• Up-front planning efforts for UPGRADE do not
  require commitment to any long term fixed
  schedule terms as a prerequisite.
• Early management attention may ensure long-term
  availability of key people needed for project and
  minimize UPGRADE project personnel turnover.

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Implementation of HSI Changes With Without HSI
Modernization Planning Process
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Defining a MCR Endpoint Vision
MCR Endpoint Vision is the MCR VISION as it is
planned to be at the plant decommissioning time
!!!
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Defining a MCR HSI Changes Migration Plan
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Approaches to the IC and MCR HSI Modernization
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WHAT ABOUT NEK MCR/MCB HSI CHANGES THAT WERE
IMPLEMENTED IN THE PERIOD 1981 - 2005?
Details of major NEK modifications implemented
since 1983 that included digital IC and HSI is
provided in the Table 1 of conference paper.
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NEK MCR/MCB HSI Changes
NEK MCR/MCB during construction year 1978
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NEK MCR/MCB HSI Changes
NEK MCR/MCB during early start-up years
1980-1981
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NEK MCR/MCB HSI Changes
NEK MCR/MCB during early operation year
1983-1990
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NEK MCR/MCB HSI Changes Major NEK
modifications implemented since 1983 that
included digital IC and HSI
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NEK MCR/MCB HSI Changes
NEK MCR/MCB after PIS upgrade years 1992-2002
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NEK MCR/MCB HSI Changes
NEK MCR with new furniture new PIS monitors
year 2004
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NEK MCR/MCB HSI Changes
NEK MCR/MCB nowadays Sept. 6, 2005
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NEK MCR/MCB HSI Changes
NEK MCR/MCB Digital HSI Details, nowadays
Sept. 6, 2005
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COMMON BASIC HSI CHARACTERISTICS OF ALL NEK
MCR/MCB HSI UPGRADES 1983 - 2005

• The new HSI equipment of digital IC and HSI
  upgrades that is installed on the MCB is used for
  monitoring only with no control functions.
• The operators workplaces/desks are still used
  for the technological process monitoring only.
• All MCR controls are still performed from the MCB
  (with auxiliary boards panels) only.
• Auxiliary systems and systems used for equipment
  monitoring have their HSI outside the MCR, while
  at the same time they provide essential
  information to operators through the annunciator
  system and/or PIS.
• Future modifications can change the above listed
  common basic HSI characteristics, but only if the
  proposed changes are in compliance with defined
  and approved NEK MCR/MCB endpoint vision and NEK
  migration path.

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HOW DOES MCR/MCB HSI OF OTHER OPERATING PLANTS
LOOK LIKE AND WHAT ARE THE IDEAS FOR NEW
CONSTRUCTIONS?
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MCR/MCB HSI of some other NPPs
Photo of an Existing U.S. NPP MCR (from
EPRI-1008122)
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MCR/MCB HSI of some other NPPs
Hybrid Control Room in Beznau NPP in Switzerland
(from EPRI-1008122)
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MCR/MCB HSI of some other NPPs
Existing MCR at TXU Comanche Peak NPP
MCR vision at TXU Comanche Peak NPP after
modernization
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MCR/MCB HSI of some other NPPs
Vision of future MCR - TXU Comanche Peak after
modernization
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MCR/MCB HSI of some other NPPs
Photo of a Modern French NPP MCR (from
EPRI-1008122)
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MCR/MCB HSI of some other NPPs
Design of a Modern Korean NPP MCR Shin Kori 34,
APR 1400 IC systems based on Westinghouse Common
Q (Advant) and Ovation platform
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MCR/MCB HSI of some other NPPs
Artists Rendition of Advanced Control Room for
ALWR (Advanced Light Water Reactor) NPP designed
by Westinghouse Electric Company
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MCR/MCB HSI of some other NPPs
Compact control room development and test
facility for ALWR (Advanced Light Water Reactor)
NPP - Westinghouse Electric Company
35
MCR/MCB HSI of some other NPPs
Full Scope Simulator room of Chinese TIANWAN NPP
(VVER-1000 type) IC systems based on SIEMENS
XP/XS platform
36
MCR/MCB HSI of some other NPPs
Artists Rendition of a Modern MCR for Japanese
Plants (from EPRI-1008122)
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PROPOSAL OF KEY NEK MCR ENDPOINT VISION ASPECTS

• The main MCB annunciator stays as it is now, or
  until sophisticated expert alarming software is
  developed, tested and ready to be implemented in
  NEK.
• MCB vertical portion (below annunciators)
  accommodates three or four large screens for
  monitoring purposes only.
• MCB control portion (almost horizontal MCB part -
  control desk with controls) accommodates only
  those controls that are used as 3D
  (Defense-in-Depth and Diversity) and/or manual
  backup functions for a reactor trip and selected
  engineered safety features controls (needed to
  establish and maintain safe shutdown). All other
  controls are moved from the MCB and their
  function is replaced by soft-controls available
  through operator workstations.
• The operators workplaces / desks accommodate
  computerized Operator Workstations (OWS) used for
  soft control and monitoring of the whole plant.

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PROPOSAL OF NEK MIGRATION PATH TO THE MCR/MCB
ENDPOINT VISION

• Among three approaches listed below, the first
  approach (Single Outage Approach) is not
  applicable for an operating plant that wants to
  minimize its outage duration and maintain the
  achieved level of plant availability,
  productivity and reliability.
• Most likely, some combination of the Phased
  Endpoint Vision (e.g. 35) and Phased
  Behind-the-Board (e.g. 65) would be the most
  appropriate solution for the NEK MCR/MCB upgrade
  migration path.
• Single Outage Approach
• Phased Endpoint Vision Approach (e.g. 35)
• Phased behind-the-Board Approach (e.g. 65)
• (For risks associated with each type of
  approaches see conference paper)

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IMPLEMENTATION RISKS GOOD PRACTICES OF NPP
MCR/MCB DIGITAL HSI UPGRADES

• There are many risks as well as good practices
  associated with the digital IC plant upgrade
  that implements the digital MCR/MCB HSI in an
  operating NPP. The most outstanding
  implementation risks are
• The NPP MCR/MCB HSI should not become the testing
  field or exhibit show of the contemporary digital
  IC and HSI technology.
• It is always better to follow good operating
  references, than to be the first one doing that.
  The NPP MCR/MCB HSI upgrade is not a "nice to
  have" feature.
• Bad planning and scheduling of the digital IC
  and MCR/MCB HSI upgrades can unnecessarily extend
  outage duration, that introduces significant cost
  increase to the project of MCR/MCB upgrade.
• Phased approach to the MCR/MCB digital HSI
  upgrade with installation of the dedicated
  computerized OWS that are designed to monitor and
  to control only one system or portion of the
  plant systems is a very bad solution. It is even
  worse if we speak about different digital IC and
  HSI systems of different vendors.
• In cases of hierarchical connection of two or
  more IC/HSI systems it is good that the control
  is hierarchically organized, too.
• (continued on next slide...)

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IMPLEMENTATION RISKS GOOD PRACTICES OF NPP
MCR/MCB DIGITAL HSI UPGRADES (continued from
previous slide)

• The use of diverse backup digital IC and HSI
  systems can be implemented to address software
  common mode failure concerns in the MCR/MCB HSI
  and plant IC, but only for those applications
  for which this is required either by the
  regulatory requirements or by the system design
  failure mode analysis.
• In the early stages of the MCR/MCB modernization
  with phased approach, the spacing requirements
  can be challenging.
• The phased approach to the MCR/MCB digital HSI
  upgrade hides risk associated with operator's
  performance during the period in which operators
  will have to learn and to exercise on simulator a
  new concept of MCR operation before each plant
  outage startup.
• Availability of the qualified or even expert
  personnel to perform the early stages of needed
  analysis, to design, develop, evaluate and
  implement modernization can be the limiting
  factor.
• The turnover of personnel on the project team
  should be considered.
• (continued on next slide...)

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IMPLEMENTATION RISKS GOOD PRACTICES OF NPP
MCR/MCB DIGITAL HSI UPGRADES (continued from
previous slide)

• The digital upgrades of the MCR/MCB HSI can give
  pure results if not associated with the design
  review and modification (if necessary) of the MCR
  lighting.
• Capacity of the existing IC inverters used for
  power supply, capacity of the existing batteries
  that supply DC input to the IC inverters in the
  case of plant blackout, and HVAC capabilities
  should be seriously reconsidered before new
  digital IC and HSI equipment is installed in MCR
  and other electrical equipment rooms.
• Requirements for the new I/O signals have to be
  appropriately limited. The number of field
  signals connected to the digital IC platform in
  the upgraded plant is usually much smaller than
  it would be in the new designed plant.
• We must accept the fact that for some auxiliary
  systems it is more appropriate to have local
  digital HSI used for control and supervision,
  while the system status and the most important
  signals are transferred to the MCR via MCB
  annunciator system and/or MCR main digital HSI
  platform.

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CONCLUSION

• It is not appropriate to proceed with digital IC
  and MCR/MCB HSI-upgrades before two initial key
  aspects of the long-term modernization planning
  are defined and approved
• NEK MCR/MCB endpoint vision
• NEK migration path to the MCR/MCB endpoint vision
• After that, the implementation of smaller digital
  IC upgrades along with the activities related to
  the MCR modernization planning and HFE (Human
  Factors Engineering) program development
  implementation can be continued.
• Before any large digital IC upgrade with
  significant impact to the MCR/MCB HSI is
  implemented, the technology and architecture for
  an integrated plant digital IC and MCR/MCB HSI
  platform should be selected.
• Until replaced with the new integrated IC and
  MCR/MCB HSI platform, existing NEK PIS (Process
  Information System) stays as the only digital
  process supervision HSI installed at MCR
  operators workplaces - desks.

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SHORT TERM NEK PLAN PROPOSAL

• Found new project (ADP-1.2.601) and form a
  project team for the planning and HFE program
  development (composed in accordance with the
  recommendations of NUREG-711, Appendix A).
  Responsibility of HFE team is to prepare and
  propose for management approval several papers
  related to the digital IC upgrades and MCR
  modernization.

• DEFINITION OF HSI CHANGES Based on HFE team
  proposal of the planning outputs NEK management
  decides about NEK MCR/MCB endpoint vision and the
  migration path (guidance in EPRI - 1008122).

• HFE PROGRAM PLAN HFE team starts development of
  HFE Plan and Program (HFE Program Goals Scope
  first - guidance EPRI - 1008122).

• HFE LICENSING PLAN HFE team identifies critical
  issues and starts developing plan related to the
  licensing activities (EPRI - 1008122).

• At appropriate time, but not before HFE Plan and
  General HFE Program Goals and Scope are developed
  and approved, the technology and architecture for
  an integrated plant IC and MCR/MCB HSI platform
  should be selected.

• As a large digital IC upgrade with significant
  impact to the MCR/MCB HSI, the DEH (Digital
  Turbine Control) replacement project shall not be
  implemented before the technology and
  architecture for an integrated plant IC and
  MCR/MCB HSI platform is selected.

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END SLIDE THANK YOU FOR YOUR ATTENTION
Extended presentation of the conference paper
that was presented on the international
conference NENE 2005 - Bled was prepared for NEK
internal use only