Westinghouse Non-Proprietary Class 3© 2015 Westinghouse Electric Company LLC. All Rights Reserved....

Westinghouse Non-Proprietary Class 3 © 2015 Westinghouse Electric Company LLC. All Rights Reserved.

1

FSRUG Conference/Workshop

January 26-29, 2015

Embassy Suites, San Antonio, TX

Panfilo FedericoWestinghouse Automation and Field

Services

Recent OE for Upgrades & Support of Existing Westinghouse Feedwater Control Systems

2


Recent OE for Upgrades & Support of Existing Westinghouse Feedwater Control Systems

• OE Considerations Relative to All Phases of Upgrade Project

– OE: Design

– OE: Implementation/Test

– OE: Commissioning

– OE: Specific Examples

– OE: General Lessons Learned

from Project Experiences

59.0 PC T

100

80

20

40

60

0

A

SP PV OUT

0

20

40

60

80

100

M L

Rejectto Local

3


OE: Design

• Properly designed digital controls that integrate feed water and steam driven feed pump governor provide efficiencies that translate into additional power production revenue. This helps the business case for justifying the upgrade investment.

• Must have “experienced” personnel from vendor and utility that work as a team – include key stakeholders from day 1

Utilize personnel that know the plant design, problems, interfaces and processes

Get assigned a plant operations representative from the start to the end of the project.

This Operations Focal Point “speaks” for Operations Department.

• Early Engagement of OPS Operational needs & expectations (buy-in on features, functionality) Training constraints HFE Evaluations of MCR Layout and operational tasks

4


OE: Design (continued)

• Need to have a good understanding of plant/operations vs “build to spec”

• Carefully evaluate SPVs for cost to improvement benefits Deploy some level of input/output redundancy for functions that immediately impact

the plant in a negative way (trip, transient…) Helps with FMEA and SHA

• Consider scenario of controller redundancy failure – human error or power failures

What happens to the plant if control processing stops What happens to the plant if control processing gets restarted online – human error,

power fluctuations, or cyber attack Is there a backup layer of redundancy

• Review existing procedures for workarounds which impact control system operation

Evaluate for impacts to new control system functional design

5


OE: Design (continued)

• Consider use of dual redundant positioners on key control valves to improve system reliability and plant automation

• The pressure switches, trip solenoids, linkages and feed pump mechanical over speed are challenging to maintain – consider upgrading to improve reliability and allow on line testability

• Control valve trim should be designed/sized properly and there should be no valve sticking or binding

New digital control system will not fix valve design issues or operational problems

• Air Supply system to main feed water and bypass valves should be sized properly with enough volume so valves stroke smoothly in required time less than 20-30 secs

Air Booster/Accumulator – stroking of any one valve should not affect other valves Check Pre-load on Bypass & Main Valve actuators to ensure spring constants have

not changed from original design Check condition of diaphragms on Bypass & Main Valve actuators

6


Example GE Feedpump Project Installation

Turbine Front Standard - Before

Turbine Front Standard - After

New TDM and Trip Handle Installed

7


OE: Implementation/Test

• Ensure that digital upgrade system design meets current dynamic regulatory environment and requirements

Software Hazards Failure Modes and Effects Requirements Traceability Matrix System Security & Cyber Security

• Appropriate use of tools Plant Representative Engineering model for dynamic testing, verification

• High fidelity models focused on normal range of operation• Use as part of the factory acceptance process

Simulator for operator training With use of high-fidelity engineering models in support of

design/implementation/test, it may be likely that the plant simulator models will need to be revised

Use of Simulator or MCR for HFE Evaluation

8


OE: Implementation/Test (continued)

• Digital systems provide Configuration Management challenges

Platform configuration tools should provide levels of self documentation

Device manager software provide configuration capture features

• Review and challenge scope of modification Will modification scope fit in outage window with minimal risk Perform work that can be done pre-outage (on-line) to reduce risk Upgrade solutions should be designed to maximize installation

efficiency Use phased upgrade approach

– Allows operations “kicking of tires” & OE of first upgrade

9


OE: Commissioning

• Proven designs minimize project and outage risks – do in advance benchmarking at other sites

• Utilize a robust testing & validation plan that incorporates closed loop engineering models to ensure startup tuning is not required

• Valve and feed pump internals work during same outage as Control System Upgrade can impact control system

Valve or pump characteristics may change and impact the system expected/programmed response

• Plant operation procedures should be updated, approved and used during the initial plant commissioning and startup

10


OE: Commissioning (continued)

• Recognize that replacement Digital Positioners have internal PID control and form an outer control loop Positioner acts as a small control system Positioner/valve sub-loop has effective closed-loop

response Overall response of outer flow/level controller is

dependent upon the sub-loop response Digital positioners have capability to significantly

alter gain and/or time response for the positioner/valve combination

Do not set the tuning parameters where the positioner is very responsive

Ensure that positioner model elastomers are specified for high temperature applications

In redundant positioner schemes – disable “pressure control” mode

11


Dual Positioner Redundancy Scheme

• SLIM can maintain manual control in event there is catastrophic controller failure

• High availability: 0.99999

• Main FW hValves

12



• Ensure stakeholders and operations staff are fully trained on the system and have confidence to take the appropriate action– If in doubt leave the system in “Automatic”

• Often technicians field troubleshooting can cause system issues without realizing it – especially with redundant output circuits

• Flexible commissioning procedures need to be put in place to allow “straightforward” software or system changes (5 minute change should not take a work day to get written and approved)

• Digital systems allow the users to see things in the plant that they were not aware off – often end up chasing ghosts

• When reusing a suite of cabinets consider using a “mockup” to validate fit of new equipment, determine interferences, signal cable lengths & routing and allow training of the installation crews

13



• When reusing a suite of cabinets use a “mockup” to validate fit of new equipment, determine interferences, signal cable lengths/routing and allow training of the installation crews• When reusing a suite of cabinets use a “mockup”

to validate fit of new equipment, determine interferences, signal cable lengths/routing and allow training of the installation crews

14


Retrofitted Cabinet with DCS Equipment

15


OE: Specific Examples

• Example 1: Clinton B Feed Pump

– HP Control Valve Leakage

Caused non-responsive control when transitioning from HP to LP Valve

Currently monitor and avoid area; keep recirculation valves open until High Power mode

Plans to fix leakage in next outage Strong technical team onsite identified problem early but

customer was convinced it was control system

New digital control system will not fix inherent feed pump or valve design issues or operational problems

16


OE: Specific Examples (continued)

• Example 2: Vogtle

– Water Leakage into DVC6200 Valve Positioner

Water Caused it to fail over a long period of time where positioner switched from “travel mode” to “pressure control mode” – feedback matched demand (acted like an I/P)

Control system sees nothing is wrong Positioner should have been configured to disallow “pressure

control mode which is a health degradation which DCS acts upon Speed pump caused valve to maintain level until valve closed

New digital control system will not fix inherent feed pump or valve design issues or operational problems

17



• Example 3: Wolf Creek

– Testable Dump Manifold (TDM) Clogged

Issue found during outage testing Existing filter housing selector switch for the duplex filter was not

replaced during installation; it was re-oriented and reused. The orifices in the TDM were clogged due to particulate

dislodged from the re-used filter housing Any particulate or scaling on pressure tubing can be loosened

during trip testing due to the shock/vibration as well

When re-using equipment, verify status of equipment and downstream equipment requirements

18



19


OE: General Lessons Learned from Project Experiences

• Clear project definition Address constraints (Org/Op)

• Project Cost/Risk Drivers Identify & Manage “First-Time” elements You cannot please everyone – tradeoff functional enhancements vs

costs to implement

• Stakeholder involvement throughout Early recognition of schedule demands, implications

• Application of the “right”, proven technology

• Disciplined design process – control scope creep

• Thorough system testing and validation

20


OE: General Lessons Learned from Project Experiences

• Project management and control Effective risk management Focus teams, strong relationships

• Monitor industry events (INPO, EPRI, etc) and evaluate their applicability and impact

• Perform Installation readiness reviews involving all stakeholders to identify risks and minimize “surprises”

• In a multi-unit design, take lessons from the lead unit and fold back into the follow on units

Successful Digital Upgrades can be achieved when the right technology & personnel are applied and the scope is clear

21


OE: Utilizing Experienced Personnel

• Even with product standardization, few upgrade projects are “cookie cutter” and use of experienced personnel avoid unnecessary and non-productive activities– Utilize vendor and utility personnel that know the plant, interfaces

and processes

• Involve plant operations personnel from the beginning to the end of project and identify an operations contact that “speaks” for Operation Department.

• Issues cannot be totally eliminated, project challenges will come when least expected – Murphy is always lurking around the corner

• Actively utilize Human Performance tools for continuous quality improvement and anticipation of problems

• A strong technical team can overcome most issues thrown at them

22


Utilizing Experienced Personnel

Almaraz Feed Pump Junction Box

23


Questions?

Westinghouse Non-Proprietary Class 3© 2015 Westinghouse Electric Company LLC. All Rights Reserved....

Documents

Transcript of Westinghouse Non-Proprietary Class 3© 2015 Westinghouse Electric Company LLC. All Rights Reserved....