Successful Digital Upgrades:

Lessons Learned

February 2015

Ryan Marcum, Technical Sales Consultant

Invensys Nuclear Group

Digital controls upgrades increase asset reliability and reduce operating costs.

Upgrading with advanced digital-based controls is the obvious solution, but that’s

not always a straightforward exercise for many stations because of the complexity

and regulatory oversight. This presentation will discuss Invensys experience and

lessons learned in such projects, looking at the drivers for upgrade, the preparation

of the specification, and the issues to tackle: system selection, project, HMI, cyber

security, simulators.

Agenda

• Reasons for Digital• The Control System Specification• FW Problems Resolved by Digital Upgrades• Digital Upgrade Project Issues• Cyber Security Issues• Plant Wide Challenges• Celebrity Cameos

Reasons for Digital

• Obsolescence• Increase reliability / decrease maintenance &

surveillance• Automated plant startups• Precise control = fewer plant disturbances• Commonality between digital platforms• Reduce single points of vulnerability (SPV)• These advantages ultimately mean less outages

Advantage: 1E to 3E Transition

• During change in requested power output the feed water system transitions from one element control to three element control using split range of the bypass and main valves.

• The old way: switching to manual controls the operators bump the bypass and main valves by hand.

• Requires experience to execute correctly.

• High chance of causing a fault in the process.

• The digital way: Set it and forget it. Automatic transition function of the feed water digital controller. Seamless split range follows a nice control curve.

Advantage: Redundancy

• Not only applied to the field instruments

• I/O at the controller

• Firmware

• Communications

Problem: Instrument Precision

• Example: Feed water Heater system digital upgrade

• Replaced Digital Level Measurement Devices & Digital Valve Controllers

• Old pneumatic system fluctuated levels as much as 30%

• Forced to divert flow for maintenance costing lower output and downtime

• New digital system

• Easy to demonstrate in the field

• Accurate levels within ½ inch

• Direct feedback between DLMD & DVC

• Less maintenance required

Source: http://www.documentation.emersonprocess.com/groups/public/documents/articles_articlesreprints/

feedwater_heater_systems_updat.pdf

Problem: Equipment Failures / Reliability

• Example: Air operated valve positioner failed

• Retaining clip vibrated loose

• False High-High Level alarm

• Level in steam shifted followed by slight reactor power transient

• New digital system

• Performs automated advanced diagnostics

• Historical data collection and retrieval

• Maintenance time greatly reduced

Source: http://www.tj88.cn/down/down/fisher/upgrading_to_digital_position

The Control System Specification

• Educate and understand what is possible for digital• Other Industries have been using digital systems for many years

• Define the functionality you will require in your system and ask for it – be very clear

• Develop a well defined I/O list to include in the specification. This will result in more accurate proposals from the vendors to start the project off right

• Work with the vendor up front to develop a Software Requirement Specification rather than a bid spec

• Not every requirement in the spec is attainable. Be open to compliance negotiation and alternative engineered solutions.

The Specification (cont’d)• Decide upfront what documentation the vendor will be responsible

to supply and clearly identify this in the specification

• Determine the level of SQA that will be required. Make sure you understand your requirements so you can explain it to the vendor

• Example: applying 1E requirements to Turbine Controls

• Do not take the “Kitchen Sink” approach when listing Codes and Standards that the vendor is required to meet

• Increases the risk factor to the vendor

• Increases cost

• Penalized by Purchasing

• Create a Dedicated Specification Team

• Focus and be educated – digital issues and products

• The more the spec is defined and accurate the better vendor design and pricing will be

The Specification (cont’d)

• Give yourself enough time to write a good specification and have it reviewed. This effort is normally underestimated.• Common case - spec is issued late, but vendor

expected to meet original schedule

• Make sure the schedule is realistic• Un-realistic schedules increase pricing

• Don’t forget about the Simulator Upgrade• Should have a stronger focus since it is usually the

first to be implemented

Cultural Issues of Upgrading• Site engineering experience with digital technology is historically very

limited and plant procedures initially will not be in-place to evaluate digital modifications.

• Operations personal initially will have very little or no experience with the digital hardware or the associated software.

• Training and experience will be needed for everyone. Experienced on-site staff will require the appropriate level of knowledge for digital positioners.

• Culturally there was concern about Digital ‘bugs’ heard in the industry historically and the possibility of malfunctions during the life cycle use in the plant.

Upgrade Project Lessons Learned• Create a Modernization Team - Assign the proper digital-savy

personnel for the project• Design • System Engineering• Operations• Simulator• Maintenance• IT

• Understand and control design freeze

• Contract and sub-supplier management

• Localize as much as possible – not only project staffing, include material supply, qualification, testing and commercial grade dedication

Lessons Learned (cont’d)

• Early mobilization of core engineering and program management teams to establish effective processes– Introduce rigorous monthly reporting

– Effective and empowered steering committee

• Your vendor must be flexible to well-defined small additions that surface during the project but must resist scope creep unless schedule and cost impacts are taken into account

• Train key project personnel early in the project so they have better input during the project

Lessons Learned (cont’d)Upgrade the Simulator

• Should be an integral part throughout the project life cycle

• Look for a simulator solution that gives a benefit to the project.

– Run the exact control code from the controller against the process model in the plant simulator

• Use the plant simulator to do a thorough dynamic test on the system

• Utilize the simulator to streamline the alarm management

Human Machine Interface

• Determine MCR/HMI design as soon as possible

• Perform HFE early – changes can cause significant impacts

• Ensure platform ability to meet all control room requirements

• Eliminate hard panels whenever possible

•Involve Operations throughout the HMI design. Their acceptance is of absolute importance.

Cyber Security Issues

• Minimize connections between the control network and corporate networks and only then through firewalls and buffers

• Do not connect the control network to the internet

• If possible limit communications to a unidirectional output from the safety system to the plant computer and plant historian

Plant Wide Challenges - Global

• Digital systems significant challenge in all new builds globally today• Staff that truly understands the design, design change impacts in digital

space, required documentation and maintenance, IV&V

• Regulatory challenges – not harmonized globally

• Need a focused design team to develop architecture from asset management down to control system components

• Need to challenge the regulating body to reduce surveillance and testing due to more reliable and available technology

• Complexities of digital still not fully understood by industry

• Required to meet multiple global standards and Regulatory positions • IEEE, IEC, RCC etc… all similar but different

Lungmen Advanced Control Room

Fuqing Unit 1,2 Simulator

Major Control Systems:

Parting Takeaways

• Work with the digital vendor in a culture of shared responsibility. These partnered relationships lead to best understandings and results. 

• Avoid adversarial situations driven by cost or schedule pressure.  Everyone wants the project to succeed and the plant to be happy.

Questions?

Thank You for your attention

Successful Digital Upgrades:Lessons Learned