DCL-11-104, Attachment 9: Revision 1 to 10115-J-NPG, Diablo Canyon Power Plant Units 1 & 2 Process Protection System Replacement Controller Transfer Function Specification.
Text
Enclosure Aftachment 9 PG&E Letter DCL-1 1-104 10115-J-NPG Revision 1, "DCPP Units I & 2 Process Protection System Replacement Controller Transfer Function Specification" (LAR Reference 120)
Specification No.: 10115-J-NPG, Rev. 1 Title, Process Protection System Controller Transfer.Functions Design Input Specification Project: Diablo Canyon Power Plant, Units 1 & 2 Date 03/09/2011 Departmcnt/Group:
Engineering Projects/lnstrumentation and Controls Structure, System or Component:
Process Protection.System (System 38)Type or Purpose of Specification:
Design of Controller Transfer Functions for the Process Protection System (PPS)No. of Sheets: PREPARER: VERIFIER: COORD SECT: ,31 (inc. cover)Signature R Lint J Hefler.JReinholdt Nuclear Safety Related: Yes X No I0CFR2l Applies: Yes X No Graded Quality: Yes _ No X Section Date PSSA 03/08/2011 PSSA 03/08/2.0 i PSSA 03/08/2011 N/A N/A N/A N/A DE 03/09/2011 SEISMIC APPROVAL:
N/A ENVIRON. APPROVAL:
N/A LEAD MGR APPROVAL:
R Klimczak Enter the professional engineer's (PE) full name and registration number, or stamp, or seal and expiration date in this space.RECORDS OF REVISIONS Revision Revised Verified Coord APPROVAL Number Date Reasons for Revision By By BQ E.PE G 0 Initial Iss c for Use .R.L m -_ N/A N/A JA ,L I I .o / lt Sec Rcvision Summary 6,11'14-1,,i
ýA I..,ft,,Y I,. -
Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page ii of iii Revision Number Affected Pages Reason for Revision 0 All Initial issue Section 2.4.1 Revised to clarify Lead/Lag Filter equation.Section 2.6.1 Revised to clarify Rate/Lag Filter equation.Added new section to define Thot Estimate Compensation Section 2.14.2 Algorithm.
i PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page iii of iii CONTENTS I INTRO DUCTION ...................................................................................................................................
1 1 .1 P U R P O S E .........................................................................................................................................
1 1 .2 S C O P E .............................................................................................................................................
1 1 .3 A C R O N Y M S .......................................................................................................................................
1 1 .4 R E F E R E N C E S ....................................................................................................................................
2 2 CONTROLLER TRANSFER FUNCTION REQUIREMENTS
...........................................
...... 3 2 .1 O V E R V IE W ........................................................................................................................................
3 2.2 TRANSFER FUNCTION:
INPUT SCALING .........................................................................................
3 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.10 2.11 2.12 2.13 2.14 2.15 2.16 TRANSFER FUNCTION:
RTD RESISTANCE TO TEMPERATURE CONVERSION
.....................................
4 TRANSFER FUNCTION:
LEAD/LAG FILTER .......................................................................................
4 T RANSFER FUNCTIO N : LAG FILTER ....................................................................................................
5 TRANSFER FUNCTION:
RATE/LAG FILTER ..........................................................................................
6 TRANSFER FUNCTION:
DTTA TAVG CALCULATION
.........................................................................
7 TRANSFER FUNCTION:
NORMALIZED POWER (PB) CALCULATION
....................................................
7 TRANSFER FUNCTION:
DTTA DELTA-T CALCULATION
.....................................................................
8 TRANSFER FUNCTION:
OVERTEMPERATURE DELTA-T (OTDT) SETPOINT CALCULATION
......................
8 TRANSFER FUNCTION:
OVERPOWER DELTA-T (OPDT) SETPOINT CALCULATION
...........................
10 TRANSFER FUNCTION:
SENSOR QUALITY ALGORITHM 2 (SQA2) ..................................................
12 TRANSFER FUNCTION:
SENSOR QUALITY ALGORITHM 3A AND 3B (SQA3A/SQA3B)
....................
14 TRANSFER FUNCTION:
THOT STREAMING FACTOR CALCULATION
........................................................
26 TRANSFER FUNCTION:
STEAMFLOW COMPENSATION
.......................................................................
27 TRANSFER FUNCTION:
STEAM GENERATOR LOW-LOW LEVEL TRIP TIME DELAY ................................
28 PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 1 of 28 1 Introduction
1.1 Purpose
The purpose of this Specification is to provide vendors with details necessary to develop the appropriate algorithms to implement the Controller Transfer Functions specified in the Process Protection System (PPS)Functional Requirements Specification (FRS) [Reference 1.4.1.1].1.2 Scope The PPS FRS [Reference 1.4.1.1] identifies the requirements that must be implemented by the PPS and is written in terms that are hardware independent.
This specification supplements the PPS FRS by providing details for developing algorithms for use by a digital system to implement the PPS FRS specified controller transfer functions.
All transfer functions specified in the PPS FRS (with the exception of bistable comparators) are included in this specification with the appropriate PPS FRS requirement section identified for traceability purposes.1.3 Acronyms 1.3.1 Acronyms ACRONYM DEFINITION CFR Code of Federal Regulations DCPP Diablo Canyon Power Plant DTTA Delta-T / Tavg FRS Functional Requirements Specification OPDT Overpower Delta-T OPSP Overpower Setpoint OPTR Overpower Turbine Runback OTDT Overtemperature Delta-T OTTR Overtemperature Turbine Runback PG&E (PGE) Pacific Gas & Electric Company PLS Precautions, Limitations, and Setpoints (document)
PPS Process Protection System RCS Reactor Coolant System PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 2 of 28 ACRONYM. DEFINITION RTD Resistance Temperature Detector RTP Rated Thermal Power SQA Sensor Quality Algorithm 1.4 References
1.4.1 Implementing
Documents (Use Latest Revision)1.4.1.1 DC 663195-44-1, DCPP Units 1 & 2, Process Protection System Functional Requirements Specification (Altran Solutions Corporation Document 08-0015-SP-001) 1.4.1.2 Technical Specifications, DCPP Units 1 and 2, Appendix A to License Nos. DPR-80 and DPR-82, as amended 1.4.1.3 DC 663229 -47, Precautions Limits and Setpoints Document (PLS)1.4.1.4 PG&E IDAP CF2.1D9, Software Quality Assurance Plan, Software Development 1.4.1.5 DCPP Maintenance Scaling Calculation (Unit 1) SC-I-36-M.2 1.4.1.6 DCPP Maintenance Scaling Calculation (Unit 2) SC-I-36-M.2 1.4.1.7 DCPP Maintenance Scaling Calculation (Unit 1) SC-I-36-M.5 1.4.1.8 DCPP Maintenance Scaling Calculation (Unit2) SC-I-36-M.5 PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 3 of 28 2 Controller Transfer Function Requirements
2.1 Overview
The PPS FRS [Reference 1.4.1.1] specifies that controller transfer functions be provided to handle various control actions necessary to implement protection channel functions.
The methods to be utilized to implement the specified controller transfer functions are included in this specification.
The methods defined in this section are acceptable.
Any alternate method proposed by a particular vendor must be presented with proof of equivalence for acceptance for use by PG&E. Any such acceptance by PG&E will result in a revision to this specification to document the acceptability for use of the methodology proposed by the vendor.Certain controller transfer functions that satisfy Technical Specification
[Reference 1.4.1.2] requirements must/shall be implemented as shown in this specification.
This requirement will be specifically identified where that function is described in this specification.
2.2 Transfer
Function:
Input Scaling 2.2.1 Input Scaling Implementation Scaling shall be implemented as follows: N= m*X+b Where: N = input scaling value (engineering units)M = gain (constant)
X = transmitter input (engineering units)b = offset (constant)
2.2.2 Input
Scaling capability shall be provided for the following PPS functions:
a) All analog inputs [PPS FRS 3.2.1.13.2]
- i. m (gain) shall be set to one (1) unless specific scaling requirements are specified in the PPS FRS ii. b (offset) shall be set to zero (0) unless specific scaling requirements are specified in the PPS FRS b) Reactor Coolant Flow [PPS FRS 3.2.2.13.1]
- i. Tuning constant ranges: [PPS FRS 3.2.1.14.3]
ii. Information:
gain (m) and offset (b) values are determined per Scaling Calc SC-I-36-M.2
[1.4.1.5, 1.4.1.6]c) Steamflow
[PPS FRS 3.2.9.13.2]
- i. Tuning constant ranges: [PPS FRS 3.2.1.14.3]
ii. Information:
gain (m) and offset (b) values are determined per Scaling Calc SC-I-36-M.5
[1.4.1.7, 1.4.1.8]PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 4 of 28 2.3 Transfer Function:
RTD Resistance to Temperature Conversion 2.3.1 RTD Resistance to Temperature Conversion Implementation Resistance to temperature conversion shall be implemented as follows: RS(T)= a + bT + cT 2 Where: RS(T) = resistance in ohms (actual measured reading)T = temperature in degrees F a, b, c = RTD constants from the RTD calibration curve (manually input for each RTD)Hence: T -b+ -v/b 2 -4c(a -RS(T))2c 2.3.2 Resistance to temperature conversion shall be provided for the following PPS functions:
a) Wide Range Reactor Coolant Temperature
[PPS FRS 3.2.3.13.1]
- i. Tuning constant ranges: a, b, c values per individual RTD calibration curve.b) DTTA (Narrow Range Hot and Cold Leg Temperatures)
[PPS FRS 3.2.5.13.5]
- i. Tuning constant ranges: a, b, c values per individual RTD calibration curve.c) Pressurizer Vapor Temperature
[PPS FRS 3.2.8.13.1]
- i. Tuning constant ranges: a, b, c values per individual RTD calibration curve.2.4 Transfer Function:
Lead/Lag Filter 2.4.1 Lead/Lag Filter Implementation Lead/Lag filters shall be implemented as follows: Reference equation: Y(n) = C1
- X(n) + C2
- X(n- 1) + C3
- Y(n- 1)Where: Y(n) = present output value (engineering units)X(n) = present input value (engineering units)PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 5 of 28 X(n-1) = previous cycle input value (engineering units)Y(n-1) = previous cycle ouput value (engineering units)Coefficient C1 *2*td +T Coefficient 02= G*d2*t n- T Coefficient 03- (2*TT)~2*Td + T Where: G = Gain (equal to 1 unless otherwise specified)-In = user entered lead time constant (seconds)Td = user entered lag time constant (seconds)T = cycle time in seconds To provide a unity transfer function (output = input), set lead time constant (Tn) and lag time constant (Td) equal to 0.0.2.4.2 Lead/Lag Filters shall be provided for the following functions:
a) DTTA Tavg [PPS FRS 3.2.5.13.2]
- i. TaVgLEAD/LAG
= Y (Lead/Lag filter output value per Section 2.4.1)ii. (Tavg -Toavg) = X (Lead/Lag filter input per Section 2.4.1)iii. Tuning constant ranges: [PPS FRS 3.2.5.14.7].
b) DTTA Delta-T [PPS FRS 3.2.5.13.2]
- i. ATLEAD/LAG
= Y (Lead/Lag filter output value per Section 2.4.1)ii. Calculated AT = X (Lead/Lag filter input value per Section 2.4.1)iii. Tuning constant ranges: [PPS FRS 3.2.5.14.7].
c) Pressurizer Pressure reactor trip compensation
[PPS FRS 3.2.7.13.1]
- i. Tuning constant ranges: [PPS FRS 3.2.7.14.6].
d) Steamline Pressure [PPS FRS 3.2.10.13.1]
- i. Tuning constant ranges: [PPS FRS 3.2.10.14.4]
2.5 Transfer
Function:
Lag Filter 2.5.1 Lag Filter Implementation PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 6 of 28 N The Lag Filter shall be implemented using the same format as the Lead/Lag Filter described in Section 2.4 with the lead time constant (T) set to 0.0.2.5.2 Lag filters shall be provided for the following PPS functions:
The following functions require Lag Filters for other than process noise filtering purposes: a) Low pass (Lag) filtering capability shall be provided for all analog inputs [PPS FRS 3.2.1.12.2]
- i. Lag time constant shall be tunable as specified in the referenced PPS FRS section.ii. Lag filter (time constant) shall be adjusted as necessary to provide attenuation of process noise.iii. Lag time constant shall be set to 0.0 if not required for process noise attenuation.
iv. Adjustment of the Lag time time constant will be per administrative procedure.
b) DTTA Narrow Range Tcold [PPS FRS 3.2.5.13.1]
- i. Each DTTA Tcold input shall be provided with a Lag Filter.ii. Tuning constant ranges: [PPS FRS 3.2.5.14.7]
c) DTTA Narrow Range Thot [PPS FRS 3.2.5.13.1]
- i. Each DTTA Thot input shall be provided with a Lag Filter.ii. Tuning constant ranges: [PPS FRS 3.2.5.14.7]
d) Calculated Thot Streaming Factor [PPS FRS 3.2.5.13.1]
- i. Each calculated Thot streaming factor output shall be provided with a Lag Filter.ii. Tuning constant ranges: [PPS FRS 3.2.5.14.7]
2.6 Transfer
Function:
Rate/Lag Filter 2.6.1 Rate/Lag Filter shall be implemented as follows: Reference equation: Y(n) = C1 * (X(n)- X(n -1)) + C2
- Y(n -1)Where: Y(n)X(n)X(n-1)Y(n-1)-present output value (engineering units)= present input value (engineering units)= previous cycle input value (engineering units)= previous cycle output value (engineering units)PG&E Spec. No.10115-J-NPG Rev. 1I PPS Controller Transfer Functions Design Input Specification Page 7 of 28 Coefficient C1 G*2*" 1 , t2*-d + T)Coefficient C2 (2* T .d T-~2* d +T)Where: G = Gain (equal to 1 unless otherwise specified)"In = user entered rate time constant (seconds)= user entered lag time constant (seconds)T = cycle time in seconds 2.6.2 Rate/Lag filters shall be provided for the following functions:
a) Tavg input to DTTA OPSP calculation
[PPS FRS 3.2.5.13.3]
- i. Calculated Tavg = X (Rate/Lag filter input value per Section 2.6.1).ii. Tuning constant ranges: [PPS FRS 3.2.5.14.7]
b) Steamline Pressure [PPS FRS 3.2.10.13.2]
- i. Gain for steamline pressure Rate/Lag shall be = -1 ii. Tuning constant ranges: [PPS FRS 3.2.10.14.4]
2.7 Transfer
Function:
DTTA Tavg Calculation 2.7.1 DTTA Tavg Calculation Algorithm
[PPS FRS 3.2.5.13.4]
DTTA Tavg shall be calculated as follows: mfhavg + Tfcavg Tavg = 2.0 Where: Tavg = calculated loop average temperature (OF)Tfhavg = calculated loop average hot leg temperature (OF)Tfcavg = calculated loop average cold leg temperature (OF)Note: Tfhavg and Tfcavg values are determined by the SQA3A(B) [Section 2.13] and SQA2[Section 2.12] algorithms.
2.8 Transfer
Function:
Normalized Power (PB) Calculation PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 8 of 28 2.8.1 Normalized Power calculation algorithm
[PPS FRS 3.2.5.13.11]:
Normalized Power shall be calculated as follows: PB -Tfhavg -Tfcavg ATo Where: PB = normalized power (unitless)
Tfhavg = calculated loop average hot leg temperature
(°F)Tfcavg = calculated loop average cold leg temperature (OF)AT° = user entered tuning constant representing the loop specific DT at rated thermal power (OF)PB = 0.0 when calculated PB < 0.0 PB = 1.5 when calculated PB > 1.5 Note: Tfhavg and Tfcavg values are determined by the SQA3A(B) [Section 2.13] and SQA2[Section 2.12] algorithms.
2.9 Transfer
Function:
DTTA Delta-T Calculation 2.9.1 DTTA Delta-T Calculation Algorithm
[PPS FRS 3.2.5.13.4]
DTTA Delta-T shall be calculated as follows: AT= PB*100 Where: AT = reactor power equivalent of loop differential temperature (equivalent reactor power units)PB = normalized power (unitless) 2.10 Transfer Function:
Overtemperature Delta-T (OTDT) Setpoint Calculation 2.10.1 DTTA OTDT Setpoint Calculation Algorithm
[PPS FRS 3.2.5.13.6]
Note: Tech Spec requirement
-no change to algorithm allowed.DTTA OTDT Setpoint shall be calculated as follows: OTDTsetpoint
= AT° * [Ki -K2* TaVgLEAD/LAO
+ K3* (P -p-) -fi(Al)]Where: AT 0 = loop specific indicated AT at rated thermal power (expressed in equivalent reactor power units)Tavg = measured Tavg signal (OF)T~avg = nominal Tavg at rated thermal power (OF)PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 9 of 28 P = pressurizer pressure (psig)P° = nominal RCS operating pressure (psig)s = Laplace transform operator (sec-')K 1 = user entered tuning constant (unitless)
K 2 = user entered tuning constant (/OF)K 3 = user entered tuning constant (/psig)f,(AI) = flux imbalance as shown below (% of rated thermal power)TaVgLEAD/LAG
= see Section 2.4.2 Ranges for tuning constants:
[PPS FRS 3.2.5.14.7].
PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 10 of 28 fi(Al)0Q N ly No A[Where: Al = the difference between the upper and lower calibrated ion chamber current readings A = breakpoint (user entered tuning constant)B = slope (user entered tuning constant)Q = limit (user entered tuning constant)D = breakpoint (user entered tuning constant)N = slope (user entered tuning constant)C = limit (user entered tuning constant)Ranges for tuning constants:
[PPS FRS 3.2.5.14.7].
2.10.2 The input to the OTDT temperature comparator shall be: ATLEAD/LAG
-OTDTsetpoint ATLEAD/LAG
= see Section 2.4.2 Ranges for tuning constants:
[PPS FRS 3.2.5.14.7].
2.10.3 An OTDT Reactor Trip shall occur when: ATLEAD/LAG
>- OTDTsetpoint ATLEAD/LAG
= see Section 2.4.2 Ranges for tuning constants:
[PPS FRS 3.2.5.14.7].
2.10.4 An OTDT Turbine Runback shall occur when: ATLEAD/LAG
-OTDTsetpoint
>- OTTRsetpoint ATLEAD/LAG
= see Section 2.4.2 Ranges for tuning constants:
[PPS FRS 3.2.5.14.7].
2.11 Transfer Function:
Overpower Delta-T (OPDT) Setpoint Calculation 2.11.1 DTTA OPDT Setpoint Calculation Algorithm
[PPS FRS 3.2.5.13.7]
PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 11 of 28 Note: Tech Spec requirement
-no change to algorithm allowed.DTTA OPDT Setpoint shall be calculated as follows: OPDTsetpoint
= AT 0 * [K4- K5* TavgRATE.AAG-K6 * (Tavg- T'avg)- f2(AI)]Where: AT = loop specific indicated AT at rated thermal power (expressed in equivalent reactor power units)Tavg = measured Tavg signal ('F)T/avg = nominal loop specific indicated Tavg at rated thermal power ('F)s = Laplace transform operator (sec-1)K 4 = user entered tuning constant (unitless)
K 5 = user entered tuning constant (/°F)K 6 = user entered tuning constant (/°F)f 2 (AI) = flux imbalance as shown below (% of rated thermal power)TavgRATE/LAG
= see Section 2.6.2 Note: f 2 (AI) shall be 0% of rated thermal power for all Al at DCPP.Ranges for tuning constants:
[PPS FRS 3.2.5.14.7].
f2(AI)-N-Al Where: Al = the difference between the upper and lower calibrated ion chamber current readings F = breakpoint (user entered tuning constant)V = slope (user entered tuning constant)W = limit (user entered tuning constant)I = breakpoint (user entered tuning constant)J = slope (user entered tuning constant)H = limit (user entered tuning constant)Ranges for tuning constants:
[PPS FRS 3.2.5.14.7].
2.11.2 The input to the OPDT temperature comparator shall be: ATLEAD/LAG
-OPDmsetpoint PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 12 of 28 ATLEAD/LAG
see Section 2.4.2 Ranges for tuning constants:
[PPS FRS 3.2.5.14.7].
2.11.3 An OPDT Reactor Trip shall occur when: ATLEAD/LAG
>- OPDTsetpoint ATLEAD/LAG
= see Section 2.4.2 Ranges for tuning constants:
[PPS FRS 3.2.5.14.7].
2.11.4 An OPDT Turbine Runback shall occur when: ATLEAD/LAG
-OPDT setpoint >- OPTIRsetpoint ATLEAD/LAG
= see Section 2.4.2 Ranges for tuning constants:
[PPS FRS 3.2.5.14.7].
2.12 Transfer Function:
Sensor Quality Algorithm 2 (SQA2)2.12.1 SQA2 Algorithm
[PPS FRS 3.2.5.13.8]
The SQA2 algorithm is performed to determine the average temperature of a DTTA loop cold leg channel (Tfcavg).The SQA2 Algorithm shall be implemented per Steps "a" and "b" as follows: a) Determine the SQA2 Case and perform the associated "Action" per the following Truth Table: SQA2 Algorithm Case Determination Truth Table Case Input Diag -Diag -RFS -RFS -[Action Pass Fail Yes No _2 Good Inputs (pass diagnostics and not RFS)1 TC X X Perform Consistency Check 1-Tc2 X x 1 Good Input (pass diagnostics and not RFS)2 TC1 X X Tcavg = Tt cl T2c2 X X 3 VC X X T cavg =VC xTc- X X Alarms =TRBL 4 VT, X X Tcavg =TV PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 13 of 28 T'cavg = T'c, or T', 2 (see Note 1 at end of Table)Alarms = RTD FAILURE (no Tc available)
T'cavg = TVc, or T'c 2 (see Note 1 at end of Table)Alarms = RTD FAILURE (no Tc available)
Ttcavg = T cl or Ttc 2 (see Note 1 at end of 1 Alarms = RTD FAILURE (no Tc available)
PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 14 of 28 Case Input Diag -Diag -RFS -RFS -Action Pass Fail Yes No 15 Tc X X T T cavg = V2 T'12 X X Alarms = RTD FAILURE (no Tc available) 16 T, X X T t cavg = T t c 1 or T T c 2 (see Note 1 at end of Table)V12 X X Alarms = RTD FAILURE (no Tc available)
Where: T'cavg = average cold leg temp (OF)Tfcl = filtered cold leg temperature from thermowell RTD "1" (OF)Tf.2 = filtered cold leg temperature from thermowell RTD "2" (OF)Note 1: When administratively removed from service, Tfcl or TfC 2 shall retain its last value while in service. The value of Tfcavg will be from the last Tfc (1 or 2)removed from service when both are RFS.b) Perform the following SQA2 DELTAC Consistency Checks as directed by SQA2 Case Determination Truth Table: Consistency Check 1 Truth Table Condition
< DELTAC > DELTAC Action IT'cl-m'X21 X T'cavg = (T T 1 c + T T c 2)/2 IT 21 X T-cavg = (Trc, + Tc 2)/2, Alarms = RTD FAILURE Where: DELTAC = user entered tuning constant (OF)Ranges for tuning constants:
[PPS FRS 3.2.5.14.7].
2.13 Transfer Function:
Sensor Quality Algorithm 3A and 3B (SQA3AISQA3B) 2.13.1 SQA3A/SQA3B Algorithms
[PPS FRS 3.2.5.13.9]
The SQA3A and SQA3B algorithms are performed to determine the average temperature of a DTTA loop hot leg channel (Tfhavg).
Each determines a value and the two values (TfhavgA and TfhavgB) are combined to determine theTfhavg for the DTTA channel.The SQA3A algorithm shall be used to determine the average hot leg temperature for the DTTA channel as developed from the three (3) "A" Thot RTDS (one per thermowell).
The SQA3B algorithm shall be used to determine the average hot leg temperature for the DTTA channel as developed from the three (3) "B" Thot RTDS (one per thermowell).
The SQA3 and SQA3B Algorithms shall be implemented per Steps "a" thru "e" as follows: a) Determine the SQA3 Case and perform the associated "Action" per the following PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 15 of 28 Truth Table: SQA3 Algorithm Case Determination Truth Table (Typical of SQA3A or.SQA3B)PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 16 of 28 PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 17 of 28 PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 18 of 28 PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 19 of 28 PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 20 of 28 PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 21 of 28 PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 22 of 28= (Thlest + Th2est)/2 Alarms = TRBL (<2 Good inputs this SQA3)PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 23 of 28 Case Input Diag -Diag -RFS -RFS -Action Pass Fail Yes No Th2est X X Alarms = TRBL (<2 Good inputs this SQA3)Th3est X X Where: Tfhavg = average hot leg temp for SQA3 (A or B) (OF)Thlest = filtered Thot (T-hl) corrected for hot leg streaming (OF)Th2est = filtered Thot (Tfh 2) corrected for hot leg streaming (OF)Th3est = filtered Thot (Tfh 3) corrected for hot leg streaming (OF)Note 1: These values are representative of SQA3A or SQA3B and tagnames would have"A" or "B" appended.Note 2: When administratively removed from service, Thlest, Th2est, or Th3est shall retain its last value while in service. The value of Tfhavg will be from the last Thest (1, 2, or 3) removed from service when all are RFS.b) Perform the following SQA3 DELTAH Consistency Checks as directed by SQA3 Case Determination Truth Table: Consistency Check 1 Truth Table Condition Al A2 A3 None Action> DELTAH X T t havg = (Thlest + Th2est + Th3est)/3> DELTAH X Perform Consistency Check 2 (Case 1)> DELTAH X Perform Consistency Check 2 (Case2)> DELTAH X Perform Consistency Check 2 (Case 3)> DELTAH X X Perform Delta Comparison Check 1> DELTAH X X Perform Delta Comparison Check 2> DELTAH X X Perform Delta Comparison Check 3> DELTAH X X X Perform Delta Comparison Check 4 Where: DELTAH = user entered tuning constant (OF)Thestavg = (Th lest + Th2est + Th3est)/3 (OF)Al = IThestavg
-Thlestj (OF)A2 = IThestavg
-Th2estj (OF)A3 = IThestavg
-Th3estl (OF)Ranges for tuning constants:
[PPS FRS 3.2.5.14.7].
PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 24 of 28 c) Perform the following SQA3 DELTAH Consistency Checks as directed by the SQA3 Case Determination Truth Table or the Delta Comparison Check Truth Tables: Consistency Check 2 Truth Table Case Condition
< DELTAH > DELTAH Action 1 IThlest- Th2estl X T'havg = (Thlest + Th2est)/2 IThl est -Th2estl X T'havg = (Thlest + Th2est)/2, Alarms = TRBL 2 IThlest -Th3estl X T havg = (Thlest + Th3est)/2 IThlest -Th3estl X T T havg = (Thlest + Th3est)/2, Alarms = TRBL 3 ITh2est -Th3estl X T t havg = (Th2est + Th3est)/2 ITh2est -Th3estl x T'havg = (Th2est + Th3est)/2, Alarms = TRBL Where: DELTAH = user entered tuning constant (OF)Ranges for tuning constants:
[PPS FRS 3.2.5.14.7].
d) Perform the following SQA3 Delta Comparison Checks as directed by the SQA3 Consistency Check 1 Truth Table: Delta Comparison Check 1 Truth Table Condition A2 > A3 A3 > A2 A2 = A3 Action Compare: A2, A3 X Perform Consistency Check 2 (Case 2)Compare: A2, A3 X Perform Consistency Check 2 (Case 1)Compare: A2, A3 X Perform Consistency Check 2 (Case 3)Delta Comparison Check 2 Truth Table Condition Al > A3 A3 > Al Al = A3 Action Compare: Al, A3 X Perform Consistency Check 2 (Case 3)Compare: Al, A3 X Perform Consistency Check 2 (Case 1)Compare: Al, A3 X Perform Consistency Check 2 (Case 2)Delta Comparison Check 3 Truth Table Condition Al > A2 A2 > Al Al = A2 Action Compare: Al, A2 X Perform Consistency Check 2 (Case 3)PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 25 of 28 Delta Comparison Check 4 Truth Table Condition Al > A2 > A3 > Al = A2 = A3 Action A2,A3 A1,A3 A1,A2 Compare: Al, A2, X Perform Consistency Check 2 (Case 3)A3 Compare: Al, A2, X Perform Consistency Check 2 (Case 2)A3 Compare: Al, A2, X Perform Consistency Check 2 (Case 1)A3 Compare: Al, A2, X Tfhavg = (Thlest + Th2est + Th3est)/3, A3 Alarms = TRBL e) Determine the Loop Tfhavg (from SQA3A and SQA3B results) by performing the following Truth Table (applicable)
Actions after completion of Steps "a" thru "d" above for each SQA3: Tfhavg Calculation Truth Table (from SQA3A and SQA3B results)Condition TrhavgA TthavgB Neither TRBL TRBL Action SQA3A SQA3B Alarm Alarm (1 Bad (1 Bad Input) Input)SQA3A SQA3B TRBL Alarm (< 2 X T t havg (T t havgA + mThavgB)/2 Good Inputs)TRBL Alarm (< 2 X X T t havg = (T T havgA + T'havgB)/2 Good Inputs)TRBL Alarm (< 2 X X T t havg = (T t havgA + TfhavgB)/2 Good Inputs)TRBL Alarm (< 2 X X X T T havg -(TthavgA + T'havgB)/2 Good Inputs)TRBL Alarm (< 2 X T t havg = T t havgA Good Inputs)TRBL Alarm (< 2 X X T T havg= T T havgA Good Inputs)PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 26 of 28 Condition TthavgA TthavgB Neither TRBL TRBL Action SQA3A SQA3B Alarm Alarm (1 Bad (1 Bad Input) Input)SQA3A SQA3B TRBL Alarm (< 2 X T t havg = T t havgB Good Inputs)TRBL Alarm (< 2 X X Thavg = T t havgB Good Inputs)TRBL Alarm (< 2 X X T t havg = (T T havgA + T t havgB)/2 Good inputs) Alarms = RTD FAILURE (< 2 Good Inputs SQA3A & SQA3B)2.14 Transfer Function:
Thot Streaming Factor Calculation 2.14.1 Thot Streaming Factor Calculation Algorithm
[PPS FRS 3.2.5.13.10]
The Thot streaming factor shall be determined per the following truth table: Th Streaming Factor Determination Truth Table Condition TthjA Good TrhjB Good Action (Pass Diagnostics (Pass Diagnostics and Not RFS) and Not RFS)PB -PLOW X X Sj = [((T t hjA + TrhjB) / 2) -T t havg) / PB]PB> PLOW X Sj = [(TfhjA -T-hag) / PB]PB > PLOW X Sj = [(TfhjB -T t hav) / PB]PB -PLOW Sj = Value from previous scan PB < PLOW X X Sj = Value from previous scan PB < PLOW X Sj = Value from previous scan PB < PLOW X Sj = Value from previous scan PB < PLOW Sj = Value from previous scan Where: PB = normalized power (unitless)
PLOW = lower threshold value for PB (user entered tuning constant)PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 27 of 28 Tfhavg = calculated average Thot in the DTTA loop (OF)TrhjA = value of the "A" RTD in the jt thermowell (OF)TfhjB = value of the "B" RTD in the jth thermowell (OF)j = loop Th thermowell (1, 2, or 3)Si = calculated streaming factor value for the jth thermowell RTDs (°F)Ranges for tuning constants:
[PPS FRS 3.2.5.14.7].
Si shall be available for updating SO) tuning constant.
SOj tuning constant is used to adjust the Thest value to be used in the SQA3a or SQA3B algorithm for the jth thermowell RTDs.2.14.2 Thot Estimate Compensation Algorithm
[PPS FRS 3.2.5.13.10]
The Thot streaming factor calculated for each Thot input shall be applied as a compensation factor in determining the Thot Estimate value for each Thot input as follows: Thjest = Thjf -PB
- Sj Where: Thjest = the jth filtered Th signal compensated for Thot streaming Thjf = the jth filtered Th signal (j = 1 to 6)P 8 = normalized power Sj = calculated streaming factor for the jth filtered Th signal The Thot streaming factors shall be calculated in each loop cycle but shall require user action to update the streaming factors used by the Thot Estimate algorithms.
2.15 Transfer Function:
Steamflow Compensation 2.15.1 Steam Density Calculation Algorithm:
SteamDensity
= A * (Steam Pressure in psig) + B Note: The steam density calculation is a best fit linearization of the steam density vs. pressure function.Where: A = steamflow tuning constant (user entered)B = steamflow tuning constant (user entered)Ranges for tuning constants:
[PPS FRS 3.2.9.14.1].
2.15.2 Non-compensated Steamflow Calculation Algorithm:
SF= (SteamDensity)* (SFDP -SFDPmin) for SF > SFmin (SteamDensityref)
- (SFDPmax
-SFDP min)Where: PG&E Spec. No.10115-J-NPG Rev. 1 PPS Controller Transfer Functions Design Input Specification Page 28 of 28 SF = non-compensated steamflow SF = 0 for SF < SFmin SFmin = user entered tuning constant SFDP = steamflow transmitter DP signal (% of full load DP)max = operator adjustable maximum value of SFC and SFDP signal ranges min = operator adjustable minimum value of SFC and SFDP signal ranges SteamDensityref
= user entered tuning constant derived from: "A * (Rated Steam Pressure @ Full Load) + B" (A and B from Section 2.15.1)Ranges for tuning constants:
[PPS FRS 3.2.9.14.1].
2.15.3 Steamflow Compensation Algorithm
[PPS FRS 3.2.9.13.1]
The Steamflow Compensation Algorithm shall be implemented as follows: SFC = (SFCmax -SFCmin) * (SF)1 2 + SFCmin Where: SFC = compensated steamflow (million pounds per hour)2.16 Transfer Function:
Steam Generator Low-Low Level Trip Time Delay 2.16.1 Steam Generator Low-Low Level Trip Time Delay Algorithm
[PPS FRS 3.2.11.13.3]
Note: Tech Spec requirement
-no change to algorithm allowed.The Steam Generator Low-Low Level Trip Time Delay Algorithm shall be implemented as follows: TD = A(PL) 3+ B(PL)2 + C(PL) + D Where: TD = allowable time delay (seconds) with PL _< 50% RTP TD = 0 with PL > 50% RTP PL = RCS Loop AT Equivalent to power (% RTP)A = constant (unitless)
B = constant (unitless)
C = constant (unitless)
D = constant (unitless)
Ranges for tuning constants:
[PPS FRS 3.2.11.14.3].
Note: the formula shown is functionally equivalent to the format as presented in the Technical specification.