Functional Analysis and Control System for the Thermosiphon Chiller Lukasz Zwalinski PH/DT/PO - Cooling
Introduction Cascade refrigeration system with R23 as low temperature refrigerant and R404a as high temperature refrigerant liquid tank C6F14 brine circuit Normal operation -64.93C to -70.25C Warm operation -14.85C to -20.81C Surface Normal operation evap. R23 Cascade condenser R404a Water condenser USA15 cavern Warm operation evap. Air condenser UX15 cavern ATLAS ID Detector Main control actions for R23 circuit: Flow control threw normal operation evap. => to ensure SH vapour condition Compressor speed control => to mach required load Hot gas injection control => if required capacity is less then capacity of the compressor Economizer control => high pressure liquid refrigerant sub cooling Main control actions for R404 circuit: Flow control threw cascade condenser => to ensure SH vapour condition (Normal operation) Compressor speed control => to mach required load Hot gas injection control => if required capacity is less then capacity of the compressor (Warm operation) Economizer control => high pressure liquid refrigerant sub cooling (Normal operation) Air cooled condenser fan control in case of water failure
Introduction Schneider Premium PLC based control system UNICOS framework System size (I/O number) Chiller Supplier requirements channel number J&E Hall Selected card number CERN 48 AI 3x16AI 4 AO 1x8AO 128 DI 2x64DI 64 DO 1x64DO Brine + Water (Stephane s talk) Selected card I/O number number CERN 32 AI 3x16AI 8 AO 1x8AO 64 DI 1x64DI 32 DO 1x32DO EN-CV-DC hardware standard Detector control system integration: same solution as already introduced by EN-ICE for Detector Gas Group
Control system architecture V1 DIP OWS OWS OWS Brine Thermosiphon CERN GPN Brine Chiller 1 Chiller 2 Water M340 with Multi-Port Module CPU + I/O cards I/O cards I/O cards I/O cards back plane extension back plane extension back plane extension ETHERNET IP surface Ring topology Distributed I/ O
Control system architecture V2 DIP OWS OWS OWS Brine Thermosiphon CERN GPN integration Brine + Water Chiller 1 Chiller 2 Water M340 with Multi-Port Module CPU + I/O cards I/O cards I/O cards I/O cards back plane extension back plane extension back plane extension ETHERNET IP surface Ring topology Distributed I/ O
Split of responsibilities Supplier Control & electrical & pneumatic cabinets cabled up to the terminal blocks All sensors and actuators respecting CERN standards Documents to be filled by supplier: 1. 2. Functional Analysis with P&ID 3. Instrument List Schneider 7.5 or equivalent touch panel General Control System Requirement CERN Schneider PLC and IO cards PLC and PVSS software Terminal blocks (to be installed by supplier) Templates for the documents to be delivered by the supplier Integration in CERN control systems, connection to DCS UNICOS Object List UNICOS Logic Design CERN limit Terminal block Limit of the supplier Collaboration of Supplier and CERN Software production Instance Generator Logic Generator
Status Supplier Electrical design for compressor panel CERN (Chiller) Task Status Task Status Delivered Electrical design for control cabinet Unknown? Templates for the documents to be delivered by supplier Accepted Electrical design for compressor panel (verification) Electrical design for control cabinet (verification) Templates for the documents to be delivered by supplier Accepted Functional analysis (preparation) Delivered Functional analysis (verification) Accepted Instrumentation list (preparation) Delivered Instrumentation list (verification) Accepted? Send Schneider I/O cards and terminal blocks selection (providing all details to J&E Hall) Completed Schneider I/O cards and terminal blocks order Completed Schneider I/O cards and terminal blocks installation Currently impossible Schneider I/O cards and terminal blocks shipping to J&E Hall Should be done this week UNICOS object list UNICOS object design Should start soon PLC software production PVSS software production Should start soon Mirror software tests Not started
Functional analysis organization In accordance with EN-ICE template functional analysis contains: 1. General process description 2. Process decomposition 3. UNIT A 3.1 UNITA controlled devices description: type + parameters 3.2 Operational states description a) Definition b) Transition condition c) Logical sequences d) Sub unit and actuators logic 3.3 User command definition 3.4 Computed variables 3.5 UNIT / PCO Alarms a) Hardware b) Software 3.6 Actuator alarms a) Hardware b) Software 3.7 Actuator alarms parameters recipes parameters 3.8 Limiting conditions 4. UNIT B
Process decomposition Chiller System Chiller 1 Chiller 2 Brine Water R404 EV53003 EV53007 R23 To be defined To be defined Economizer High temperature Warm Operation Evaporator Cascade Condenser Air Cooled Condenser CV59235 CV59240 EV59246 CV59232 CV59233 F59505A F59505B F59505C F59505D Economizer Low Temperature Normal Evaporation Evaporator COMP59112 CV59301 CV59302 GT59364 CV59326 CV59330 CV59331 CV59332 CV59333 CV59318 CV59314 Has to be defined in next 2 weeks maximum COMP59502 CV59201 CV59202 CV59213 GT59263
P&ID vs process decomposition Air Cooled Condenser Economizer HT Economizer LT CV59235 Cascade Condenser Normal operation evaporator W arm operation evaporator R404 R23
Chiller 1 Option modes and operation states Option modes: MAINTANACE: In this state, all equipment is stopped and there is no way to re-activate actuators from the program. All interlocks related to this unit are disabled. OPERATION: nominal state in which Chiller is operated States: [0] Stopped: Both compressors are switched off all outputs are off except either EV53003DO or EV53007DO [1] Available for Warm Operation (WCC): The R404a compressor is not running, but is available to start, EV-53003 is confirmed open, EV-53007 is closed. The chiller is using the Water Cooled Condenser and the manual changeover valves have been set for this condenser. A C 6 F 14 pump is confirmed as running. [2] Available for Warm Operation (ACC): The R404a compressor is not running, but is available to start. EV-53003 is confirmed open, EV-53007 is closed. The chiller is using the Air Cooled Condenser and the manual changeover valves have been set for this condenser. Condenser fans are healthy and switched to auto. A C 6 F 14 pump is confirmed as running. [3] Available for Normal Operation: Both compressors are available to start. A C 6 F 14 pump is confirmed as running and either EV-53003 or EV-53007 is open. [4] Warm Operation with Air Cooled Condenser ACC: The R404a compressor is running. EV-53003 is open,ev-53007 is closed. The R23 compressor is not required, so its status is ignored. Air Cooled condenser is running. [5] Normal Operation: Both compressors are running. EV-53003 is closed, EV-53007 is open. [6] Warm Operation with Water Cooled Condenser WCC: The R404a compressor is running. EV-53003 is open, EV-53007 is closed. The R23 compressor is not required, so its status is ignored. Water Cooled Condenser is running.
Chiller 1 Transition conditions T0 = Transition from any state to STOP A C 6 F 14 pump running = 0 EV-53003 AND EV-53007 = closed EMSDI = 0 PSU1DI AND PSU2DI = 0 The R404a compressor {COMP-59502} is tripped Chiller.RunOrder falling edge T1 = Transition from STOP to Available Air Cooled Condenser A C 6 F 14 pump must be confirmed as running Either EV-53003 or EV-53007 must be open Master Emergency Stop healthy [EMSDI = 1] Either PSU1 or PSU2 healthy [PSU1DI = 1 or PSU2DI = 1] The R404a compressor is available or running The manual changeover valves have been set for air cooled condenser operation. At least three of the four air cooled condenser fans {F-59506A F-59506D} are healthy [F59506A_TDI - F59506D_TDI = 1] and switched to Auto [F59506A_A - F59506D_A = 1] T2 = Transition from STOP to Available Water Cooled Condenser: A C 6 F 14 pump must be confirmed as running Either EV-53003 or EV-53007 must be open Master Emergency Stop healthy [EMSDI = 1] Either PSU1 or PSU2 healthy [PSU1DI = 1 or PSU2DI = 1] The R404a compressor is available or running The manual changeover valves have been set for water cooled condenser operation. T3 = Transition from STOP to Available Normal Operation: A C 6 F 14 pump must be confirmed as running Either EV-53003 or EV-53007 must be open Master Emergency Stop healthy [EMSDI = 1] Either PSU1 or PSU2 healthy [PSU1DI = 1 or PSU2DI = 1] The R404a compressor is available or running The R23 compressor is available or running The manual changeover valves have been set for water cooled condenser operation. T4 = Transition from Normal Operation to Warm Operation: Whilst running in Normal Operation, The R23 compressor has either been commanded off by the operator, or switched off at the compressor starter panel [R23 Compressor AUTODI = 0], or has tripped, or is not available, AND the C 6 F 14 brine temperature TT53101< -21.0 o C. T5 = Transition from Warm Operation Water Cooled Condenser to Normal Operation: R23 compressor unit is Available AND Manual Operator transition request from Warm Operation to Normal Operation
R404 - compressor PCO operation states and transitions STOP [0][1] T0 T1 Waiting [2] T2 T0 T0 T0 Avlb. [3] T3 Run[4][5] T4 NOT T4 Run Non Eco.[6] T0 = R404.RunOrder falling edge OR the switch on the compressor starter control panel (AUTODI = 0, DI = 1 OffSt). T1 = Starts per Hour timer is running OR Stop to Start timer is running T2 = Starts per Hour timer is NOT running AND Stop to Start timer is NOT running AND starter control panel switch is in the ON position (AUTODI = 1, DI = 0 OnSt) AND (EV-53007 or EV-53003 is open) AND C 6 F 14 Pump running. T3 = Chiller start command = Chiller.RunOrder T4 = PT-59207 {R404a Compressor Discharge Pressure} <11.77 bara AND Economiser is switched off (NOT EHT.RunOrder) [0] Tripped: A Full Stop Interlock has been implemented. The compressor is not running; one or more of the compressor operating parameters has reached a software trip threshold and stopped the compressor, or a hard wired protection device has stopped the compressor. [1] Stopped: The compressor is not running, it is not tripped. The compressor has been commanded to stop either by the operator or by the switch on the compressor starter control panel (AUTODI = 0, DI = 1). [2] Waiting: The compressor is not running. It is not tripped. The starts per hour timer is running, or (EV-53007 and EV-53003 is not open), or C 6 F 14 Pump not running. [3] Available: The compressor is not running, it is not tripped, it is not waiting, the starter control panel switch is in the ON position (AUTODI = 1 DI = 0). The compressor is waiting for a command to start [4] Running Auto: The compressor has been selected to Auto on the local HMI and has been commanded to start and is running normally within the designed operating envelope and can vary its speed according to the R404a Compressor Speed Controller. [5] Running Manual: The compressor has been selected to Manual on the local HMI and has been commanded to start by the manual soft key start button on the HMI and can vary its speed according to the local soft keys Manual Speed Increase & Manual Speed Decrease. [6] Running non economised: The compressor has been commanded to start and is running normally within the designed operating envelope and can vary its speed according to the R404a Compressor Speed Controller if selected to auto, or by the local soft buttons on the HMI if selected to manual, but PT-59207 {R404a Compressor Discharge Pressure} <11.77 bara and the economiser is switched off
Summary logic description table example Actuator Stopped [1] Tripped [0] Waiting [2] Available [3] Run [4] Run Non Economized [5] Comp59502 ON ON ON MS5926 CV59201 CV59202 CV59213 AuPosR= from commisioning: 100* R404_CV59201_pl /2 AuPosR= from commisioning: 100* R404_CV59201_pl /2 AuPosR= from commisioning: 100* R404_CV59201_pl /2 IF (LS1=0 AND LS2=0) THEN (IF (ACC OR WCC) THEN Regulation ON AuPosR=TSC59263.Out O ELSE_IF Normal THEN Regulation ON AuPosR=PSC59321) ELSE_IF LS1=1 THEN IncSpd NOT permitted ELSE_IF LS2=1 THEN Decreas AuPosR by _R404_MS59263_sr every 30s (step change!) IF MC2=0 THEN AuPosR= from commisioning:100* R404_CV59201_pl /2 every 30s for Time=2s* R404_CV59201_pn pulse number until MC2=1 IF MC1=1 AND MC2=1 AND CV59201.PosSt=0.0 THEN AuPosR= from commisioning ELSE IF TT59211 > R404_CV59213_tTStart THEN SET:Regulation ON AuPosR= TC59213.OutO IF TT59211< R404_CV59213_tTStop THEN RESET: Regulation IF (LS1=0 AND LS2=0) THEN (IF (ACC OR WCC) THEN Regulation ON AuPosR=TSC59263.OutO ELSE_IF Normal THEN Regulation ON AuPosR=PSC59321) ELSE_IF LS1=1 THEN IncSpd NOT permitted ELSE_IF LS2=1 THEN Decreas AuPosR by R404_MS59263_sr every 30s (step change!) IF MC2=0 THEN AuPosR= from commisioning:100* R404_CV59201_pl /2 every 30s for Time=2s* R404_CV59201_pn pulse number until MC2=1 IF MC1=1 AND MC2=1 AND CV59201.PosSt=0.0 THEN AuPosR= from commisioning ELSE IF TT59211 > R404_CV59213_tTStart THEN SET:Regulation ON AuPosR= TC59213.OutO IF TT59211< R404_CV59213_tTStop THEN RESET: Regulation
Alarm parameters and recipes parameters Name Description Min Value Max Value Default Value Units Access Level R404_CV59202_pl R404_CV59201_pl R404_CV59213_pp R404_CV59213_mpl R404_CV59213_tTStart R404_CV59213_tTStop R404_Spare01 R404_MS59263_sr Loading Solenoid Pulse Length Unloading Solenoid Pulse Length Liquid Injection Solenoid Pulse Period Liquid Injection Solenoid Minimum Pulse Length Discharge Temperature to Start Liquid Injection Control Discharge Temperature to Stop Liquid Injection Control Not Used Speed Reduction every 30s when System Limiting 0.05 1.0 0.1 Sec Commissioning 0.05 1.0 0.1 Sec Commissioning 3.0 6.0 3.0 Sec Commissioning 0.2 1.0 0.2 Sec Commissioning 50 90 75 o C Technician 50 90 65 o C Technician 1 20 5 % Commissioning R404_CV59201_pn Number of pulses every 30s when Motor Current Limiting 1 15 5 - Commissioning
Computed variables Definition: Name Description Unit Calculation Range R404-ODP Oil Differential Pressure bar PT-59204 PT-59242 0.0-20.0 R404-OFPD Oil Filter Pressure Drop bar PT-59207 PT-59204 0.0-10.0 R404- DSH Discharge Superheat K See notes below 0.0-100.0 R404_LS1 Limit System R404_LP_LS1 OR BOOL Condition Level 1 R404_HP_LS1 OR R404_LS2 Limit System R404_LP_LS2 OR BOOL Condition Level 2 R404_HP_LS2 OR Description: Discharge Temperature (Saturated)(K) (T s at ) is calculated from this equation: T s at = A + (B x (LnP)) + (C x ((LnP)^2)) + (D x ((LnP)^3)) Discharge Superheat = Discharge Temperature (Actual)(K) Discharge Temperature (Saturated)(K) Range <-35.0,60.0> Dead band 0.085K Tsat is available and archived in PVSS Where A = 226.9570901 B = 20.82789774 C = 2.485671782 D = 0.208949075 P = PT-59207 {R404a Compressor Discharge Pressure} (bara) T s at = Tsat59207 Then: R404-DSH = TT-59211 + 273.15 - T s at
Summary and what s next? Chiller Functional Analysis and I/O List accepted on 12.10.2011 Hardware Ethernet IP tests in progress. In 2 weeks time I ll start preparation of UNICOS object list UNICOS project preparation: Excel specification PLC hardware configuration PLC & PVSS instance generation Specification SCADA server PVSS panel preparation Instance Generator MS Acsses DB Process logic programation Logic Generator SCHNEIDER Premium PLC Code compilation Commisionig & operation All generated files will be kept in SVN service.