June 17, 2006 Nuclear I&C and Information Engineering Laboratory Dept. of Nuclear and Quantum Engineering KAIST Jong Joo Sohn 증기발생기 시스템 식별 (II) (Identification of KSNP-Type Steam Generator for Control)

1 I.Introduction II.Identification of Steam Generator III.Summary IV.Future Works Contents

2 I. Introduction Previous work (IV. Future Works ) Model Identification of Primary & Feedwater temperature Structure (System Order) Selection Parameter Estimation

3 Steam Generator & FW Control Components ♦ Two(2) Control Valves : Economizer, Downcomer ♦ Two(2) Main Feedwater Pumps I. Introduction

4 Model Identification Procedure II. System Identification of SG 1. Thermal-Hydraulic Model 2. Plant Experimentation 3. Model Structure Selection 4. Model(Parameter) Estimation 5. Validation Complete If not appropriate

5 1. Thermal-Hydraulic Model : RELAP II. System Identification of SG

6 Reactor Power Steam Flowrate(kg/s) Feedwater Flowrate FW Temp. (Deg. K) Rx Power(%) WfWf △Wf△Wf WsWs △Ws△Ws TfTf △Tf△Tf ф pф p △фp△фp 5% % % % % % % % % Plant Experimentation ♦ Initial Test Conditions & amount of Step Change

7 II. System Identification of SG 2. Plant Experimentation ♦ Test on Reactor power instead of Primary temperature was performed. Because; - Simulation of Primary temperature Step changes can not be easily performed with the closed RCS loop in the current RELAP model. - Step changes of Primary temperature are rarely occurred in the operating NPPs.

8 II. System Identification of SG 2. Plant Experimentation & Model Validation (5%, 15%) ♦ Step increase in feedwater temperature step change (10 deg. K)

9 II. System Identification of SG 2. Plant Experimentation & Model Validation( 20%, 50%) ♦ Step increase in feedwater temperature step change (10 deg. K)

10 II. System Identification of SG 2. Plant Experimentation& Model Validation( 80 %) ♦ Step increase in feedwater temperature step change (10 deg. K)

11 II. System Identification of SG 2. Plant Experimentation & Model Validation (10%, 30%) ♦ Step increase in Reactor Power (1 % )

12 II. System Identification of SG 2. Plant Experimentation & Model Validation (80 %) ♦ Step increase in Reactor Power (1 % )

13 II. System Identification of SG At 5 % K = 3.23*10^(-9); Tp1 = Tp2 = Td = Tz=17800 At 10% K = 1.7*10^(-7); Tp1 = Tp2 = Td = Tz=500 ; At 15% K = 4.58*10^(-9); Tp1 = Tp2 = Td = Tz=17000 At 19% At 20% K = 8.38*10^(-9); Tp1 = Tp2 = Td = Tz=18500 At 30% K = 8.78*10^(-9); Tp1 = Tp2 = Td = Tz=18500 At 50% K = -2.18*10^(-7); Tp1 =0 Tp2 = Td = Tz=-1000 ♦ Transfer function G tf (s) from feedwater temperature to Level At 80% K = -4.30*10^(-5) Tp1 = 4.2 Tz = At 100 % 1+Tz*s G tf (s) = K * * exp(-Td*s) s(1+Tp1*s)(1+Tp2*s)

14 II. System Identification of SG ♦ Transfer function G p (s) from Reactor Power to Level At 5% At 10% K = 2.8*10^(-6); Tp1 = Tp2 = Td = Tz=500 At 15% At 19 % At 20 % At 30% K = 1.98e-005 Tp1 = 8.5 Tp2 = Td = 2 Tz = 2.0 At 50% At 80% K = *10^(-5); Tp1 =0 Tp2 = Td = Tz=-80 At Tz*s Gp(s) = K * * exp(-Td*s) s(1+Tp1*s)(1+Tp2*s)

15 III. Summary Model Tests ♦ Tests on feedwater, steam flow, feedwater temperature, and Reactor power were performed and completed ♦ Test on Reactor power instead of Primary temperature was performed Development of Transfer Function (Structures & Parameters) ♦ TFs from Steam & Feedwater to Level were successfully validated ♦ TFs from feedwater temperatre and Reactor power to Level were partly completed and validated KSNP SG System Identification for Control

16 III. Summary Identified Model will be in a form of Linear Parameter Varying Model ♦ Linear Transfer Function (MISO) : 4 Inputs, 1 Output ♦ △ L = G f (s) △ W f (s) + G s (s) △ W s (s) + G p (s) △ T p (s) + G tf (s) △ T f (s) Where G f (s) : Transfer Function bet. Feedwater Flow and Level G s (s) : Transfer Function bet. Steam Flow and Level G tp (s) : Transfer Function bet. Primary Temperature and Level G tf (s) : Transfer Function bet. Feedwater Temperature and Level

17 IV. Future Works Completion of Model Identification of Primary & Feedwater temperature Development of H  Optimal Controller (Loop-Shaping Techniques)

18 END

19 II. System Identification of SG 3. Model Structure Selection ♦ Structure of transfer function G tf (s) from FW Temperatre to Level ♦ Structure of transfer function G p (s) from Feedwater Flow to Level 1+Tz*s G p (s) = K * * exp(-Td*s) s(1+Tp1*s)(1+Tp2*s) 1+Tz*s G tf (s) = K * * exp(-Td*s) s(1+Tp1*s)(1+Tp2*s)

20 II. System Identification of SG 4. Model(Parameter) Estimation ♦ Parameters Estimation using MATLAB System Identification Toolbox - Process Model

21 II. System Identification of SG 5. Model Validation ♦ Identified Models were validated using SIMLINK & MATLAB

22 II. System Identification of SG 5. Model Validation