ML14058A173
| ML14058A173 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 02/19/2014 |
| From: | Xcel Energy |
| To: | Division of Operating Reactor Licensing |
| Wall S | |
| Shared Package | |
| ML14057A374 | List: |
| References | |
| TAC MF3275, TAC MF3276 | |
| Download: ML14058A173 (30) | |
Text
Prairie Island Nuclear Generating Plant Meeting February 19, 2014 Diesel Generator Steady State Voltage and Frequency Limits Diesel Generator Steady State Voltage and Frequency Limits
2 Agenda
Introductions Vincent
Meeting purpose Davison
Background Vincent
Applicability of industry initiatives Mathew
LAR scope Vincent
Proposed TS and Bases changes Vincent
Technical basis for changes Zamarripa
Schedule Mathew
Conclusion Davison
3 Xcel participants
Kevin Davison - Site Vice President
Marty Murphy - Director Regulatory Affairs
Joe Mathew - Design Engineering Manager
Paul Zamarripa - Engineering Supervisor
Dale Vincent - Regulatory Affairs Project Manager
4 Meeting Purpose
Establish dialog on this LAR
Applicability of industry initiative (WCAP-17308)
Proposed EDG SR changes
Basis for changes
5 Background
EDG Frequency identified in CAP - 2006
AL 98-10 compensatory measures
EDG Voltage identified in IN - 2007-09
AL 98-10 compensatory measures
Meeting with NRC - June 2008
PWROG adopt issue - 2009
PWROG meeting with NRC - 2010
6 Background
(continued)
EDG Exigent LAR - October 2010
PWROG meeting with NRC - 2011
NRC Frequency submittal finding - 2011
EDG Voltage limits revised - 2013
AL 98-10 compensatory measures revised
7 Applicability of Industry Initiatives
WCAP-17308 methodology
SRs verify EDG operate at nominal voltage and frequency
Variation from nominal treated as uncertainty
Minimal impact on supplied loads and EDGs
8 Applicability of Industry Initiatives (continued)
Assumes EDG operates at range extremes
Significant impact on supplied loads
Significant impact on EDGs
PINGP LAR will not incorporate WCAP-17308
9 LAR Scope
EDG operating voltage
EDG operating frequency
Impact on supplied loads
Impact on EDGs
AL 98-10 submittal
10 Proposed TS and Bases Changes
SS Voltage lower and upper limits
SS Frequency lower and upper limits
TS Bases changes
11 Proposed TS and Bases Changes (continued)
Current TS
SS Voltage lower voltage: 3740 VAC
SS Voltage upper voltage: 4580 VAC
SS Frequency lower limit: 58.8 Hz
SS Frequency upper limit: 61.2 Hz
12 Proposed TS and Bases Changes (continued)
Proposed TS
SS Voltage lower voltage: 4084 VAC
SS Voltage upper voltage: 4400 VAC
SS Frequency lower limit: 59.5 Hz
SS Frequency upper limit: 60.5 Hz
Proposed TS and Bases Changes (continued)
TS Revisions:
SR 3.8.1.2 - monthly test
SR 3.8.1.6 month fast start test
SR 3.8.1.9 year 24-hour run test 13
Proposed TS and Bases Changes (continued)
TS Bases Revisions:
Define steady state
Clarify purpose of steady state voltage requirement 14
15 Technical Bases for Changes
Lower voltage limit
4084 VAC
Within nominal rating of equipment
Protective relaying calculations
16 Technical Bases for Changes
Lower voltage limit (continued)
Degraded voltage setpoint basis
Ready to load relay @ V-Hz permissive bkr closure
PLC sequencing requires bus voltage > DV R/S [4027]
Lower limit > DVR setting + error + R/S > 96.8% [4027]
DV LL >94.5% used in DV calculation
Exceeds the region of degraded voltage
17 Technical Bases for Changes (continued)
Upper voltage limit
4400 VAC
Equipment ratings within nominal
Protective relaying
18 Technical Bases for Changes (continued)
ESF pump motor performance with proposed V&F limits
Motor terminal voltage affected
With 4084 VAC pumps operate within specification
Bus voltage remains above degraded voltage setpoint
19 Technical Bases for Changes (continued)
ESF pump motor performance with proposed V&F limits (continued)
Frequency affects governed by affinity laws
Pump speed (S) proportional to frequency (F)
Discharge pressure proportional to pump speed squared (S2)
Re-performed thermal hydraulic analyses
+0.5 Hz - pumps not in run-out, flow rate not excessive
-0.5 Hz - Necessary flow rates attained
20 Technical Bases for Changes (continued)
ESF Ventilation performance with proposed V&F limits
Evaluations performed
Auxiliary Building Special Ventilation (ABSVS)
Shield Building Ventilation (SBVS)
Containment ventilation
EDG Rooms
Control Room Ventilation
Safeguards Screenhouse Ventilation
21 Technical Bases for Changes (continued)
MOV performance with proposed V&F limits
MOV motor terminal voltage affected
Apply degraded voltage
Adequate torque
MOVs will operate at lower voltage limit
22 Technical Bases for Changes (continued)
MOV performance with proposed V&F limits (continued)
MOV frequency effects (continued)
Analyses assumption +1.2 Hz
Upper frequency
Increase dP 4%
Acceptable results
Lower frequency
Travel speed
Actuation time
Adequate margin
23 Technical Bases for Changes (continued)
Relay coordination and interface with TS 3.3.4 with proposed V&F limits
Calculations performed across 75% - 110% of nominal 4kV motor rating
Modeled in ETAP
Coordination acceptable
24 Technical Bases for Changes (continued)
EDG loading with proposed V&F limits
Unit 1 EDG Design Loading
Licensed under AEC SG 9 paragraph C2 guidance
2000 Hr rating or 90% of 30 Min rating (3250 kW)
Limit of 2750 kW
Unit 2 EDG Design Loading
Licensed under RG 1.9 Rev 2 paragraph C2 guidance
Predicted load < short-time rating
Limit of 5400 kW
25 Technical Bases for Changes (continued)
EDG loading with proposed V&F limits
Evaluated loads for LOOP+SI
Frequency 60.5 Hz
Applied affinity laws to inductive loads
All EDG adequately sized
D2 (Unit 1 Train B) least margin
2335 kW load vs. 2750 kW rating
26 Technical Bases for Changes (continued)
EDG loading with proposed V&F limits
Evaluated loads for SBO
10CFR 50.63 and RG 1.155
Frequency 60.5 Hz
Applied affinity laws
All EDG adequately sized
D1 (Unit 1 Train A) least margin
2560 kW load vs. 2750 kW rating
Unit 2 EDGs much more margin
Rated 5400 kW
27 Technical Bases for Changes (continued)
EDG loading with proposed V&F limits (continued)
Minimum fuel oil capacity evaluated
Calculations revised
Values in TS Bases per LA
28 Schedule
LAR drafted
Validation in progress
Adjust for meeting input
Plan to submit soon after addressing meeting input
29 Conclusion
Discussion
Questions
Closing statements