wide – wp5 achievementscse.lab.imtlucca.it/hybrid/wide/documents/im2011_07.pdf · wide...
TRANSCRIPT
WIDE – WP5 Achievements
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Agenda
• Introduction• Overview• Concluding Remarks• Discussion
WP5 Introduction
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WP5 Overview
• Proof of concept: water network
• Objectives– The role of WP5 is to validate the
concepts developed in WP2, WP3 and WP4 on a large-scale water distribution system.
– It will also serve to motivate and circumscribe the class of large-scale systems WP2, WP3 and WP4 will focus on, providing useful engineering inputs to the theoretical developments.
– The concepts will be demonstrated in a software demonstration of the entire water network using a simulation environment based on MATLAB/SIMULINK and an experimental demonstration of part of the water network.
• Tasks– T5.1 Definition of the water network
demonstration – T5.2 Dynamical model of the water network
and model decomposition– T5.3 Control design for the water network– T5.4 Development of the water demo
demonstrator – T5.4 Testing and evaluation of the solution
T5.1 Definition of the Water Network Demonstration
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Pilot Definition
• Definition of Pilot 1: DMPC of the Barcelona Water Transprot Network
– Definition of the part of Barcelona water network used to illustrate DMPC
– Definition of the control problem
• Definition of Pilot 2: Wireless Control of Valve in Barcelona Water Network
– Definition of the part of Barcelona water network used to illustrate wireless control
– Definition of the control problem
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Test Pilot 1: Demo of DMPC in the Barcelona Network
c70PAL
c125PAL
CPIV_1
d110PAP_2
C110 PAP
CPII_2
d54REL_8
d100FCE_9 c100FCE
VSJD_29C100 LLO
d80GAVi80CAS_6 i 85CRO
c80GAVi 80CAS85CRO
c70LLO
VCA_28
CRE_8
CGIV
CCA_3
d115CAST
C115 CAST VCR_27
CB_4
dPLANTA_7
ApotLL 1
CPLANTA70_6
CPLANTA50_7
d10COR_10
c10COR
PLANTA10_10
CC50_9
CC70_12c70FLL
VZF_33
VCT_34
VT_35
c100 BLLsud
VRM_32
VCO_37
CCO_16
VS_36
CE_13
VE_31 c130BAR
CF200_14CF176_15
d200BLL_11c200BLL
VF_30
d176 BARsud_13
C176BARsud
c200 BARs-c
VB_38
VP_39
VMC_44d200ALT _15
c200ALT
VBSLL _43 d200 BARnord_17c200BAR
nordd101 MIR_18
c101MIR
CA_17
c100BLLcentre
VPSJ _41
d100BLLnord _16
c100BLLnord
VCOA_40
d70BBE
c70BBE
CC100_11CC130_19
CRO_20
aMS bMS_21
aPou CAST1, 5 , 6 i 7
bPou CAST1, 5, 6 i 7
aPousB
aPousE
bPousB _26
bPousE _23
d130BAR
c140 LLO
d125PAL_1
nAportA1_19
nAportA2_21
n70PAL_20
n100LLO_22
n70LLO_23
n140LLO_24
n100BLLsud_25
n70FLL_26
n200BARs-c
n100BLLcentre_29
AportT
vAdd_45
vAdd
vAdd_47
vAdd_48
vAdd_53
vAdd _54
vAdd_55vAdd_56
vAdd_57
nAportT_32
ApotLL2
c176BARcentre
n176BARcentre
ApotA
vAdd_60
vAdd_61
VBMC_42
vAdd_64
vAdd_50
vAdd _55
vAdd_309vAdd_308
d205FON d320FON
CPI CPII CPIII
c205 FON c320FON
c356 FON
d175PAP
C175PAP i 135PAP
CP_ATLL
d82PAL_1
c82PAL
d130LSE C LSE
cLSE
A CAST 8 b CAST 8
d145 MMA
C MJ
c145MMA
C175 BVI
C MMA II
C SB C VIL 1 C SC 1 C BEG 1
d150 SBO
d175LOR
C LOR
d184ESP
d255 BEG 2
C BEG 2
d114 SCL 1
d190 SCL 2
C SCL 2
d135 VIL
d185 VIL
C VIL 2
d369BEG 3
C BEG 3
d450 BEG 4
C BEG 4
c175LOR
c185VIL
c190 SCL2
c255BEG
c150SBO
c135VIL
c114SCL
C184 ESP
C369 BEG3
C450 BEG4
d195TOR
C CRc195TOR
d147SCC
C SCC
c147SCC
d205 CES
C CES 1
C205 CES
d263CES
C CES 2
C263 CES
d252 CGL
d313 CGL
C CGLL2 (D3)
d246CGYd200 CGY
d268 CGY
c200CGY
c246CGY C252
CGL
C CGY1 (D2)
C CGY1 (D5)
C CGLL1
C CGY2
c268CGY
d361 CGY
c361CGY
C CGY3
d374 CGL
C CGLL2 (D5)
C374CGL
C313CGL
d200BSO
C BSO
c200BSO
d300 BAR
d437 VVI
C300BAR
C F300
d320 MGB
C PAP1
c320MGB c437
VVI
C MG1 C TIB
d400 MGB
C MG2
c400MGB
C MG3
c475MGB
C VVI
c541 TIB
d255CAR
C CAR
c255 CAR
d260 SGE
d328SGE
c260SGE
c328 SGE
C SG1
C SG2
d250 TBA
C250 TBA
C TBA 2
C C UAB C CS C CM
d197 BET
C UAB
d215VALL d184SMM
C SMM
d132 CMF
d200 FDM
C FDM
c238UAB
c200 FDM
c255BEG
c150SBO
c132CMF
c215 VALL
c250 VASAB
C VALL 1
C VALL2
c260VALL
c275BEV
C BEV
d169CMECTBA1
c169 CME
aPous G 3 i 4 bPou s G 3 i 4
c55BAR
d120POMC_MO
C_TP
C_SA
d171SAM
d144TPI
d190TCA
c144TPI
c144TPI c190TCA
V a 55BAR
c120POM
d117MTG
c117MTG
v117MTG
n135SCGc135SCG
d151 BON d197GUI
c151BON
c197GUI
d225GUI
c225GUI
C_BONC_GUI
1
C_GUI2
c70CFE
V_70CFE
n100BESV_BSC
c100BES
V_FoAl
C_SA
C_SCM
C-PR
VFIN176 A 140
V 200a150 AL
T
d150ALT _15
c150ALT
V -Hc176 BARn
d202CRUc202CRU
CCRU
Transport Water Network
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Test Pilot 1: Demo of DMPC in the Barcelona Network
Supervisory MPC Control Architecture
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Interface Simulator/DMPC Controller
Test Pilot 1: Demo of DMPC in the Barcelona Network
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Test Pilot 2: Demo of Wireless Control Functionalities
CABLE CONNECTION
WIRELESS CONNECTION
• The overall idea is to check the use of wireless connection between the sensors and the remote station.
• Each signal will be doubled (cable connection and wireless connection) as a protection to the overall control system. Both sets of data will be compared and contrasted afterwards.
• Double aim: a) Transference of information through wireless. b) Operational feasibility/constraints regarding the overall valve control (delays,
etc.)
Closed-loop Control of a Valve at the Regulatory Level
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Phase 1: Lab Test
Test Pilot 2: Demo of Wireless Control Functionalities
AGBAR Labs UPC Labs
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Valve and Servomotor
Flow / pressure meters
Remote stationCurrent working situation
• Pressure and flow data are stored every 0.4 s in the remote station.• Input data + desired pressure downstream the PID controller in the remote station changes valve position.• The remote station sends flow and pressure data every 4-5 s to the Control Centre.• Set points of pressure or flow can be sent from the Control Centre to the remote station when necessary.• Alarms due to values out of the acceptable range also pop up at the alarms panel in the Control Centre.
Phase 2: Real Test
Test Pilot 2: Demo of Wireless Control Functionalities
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Demonstration Objectives
• Demonstrate the benefits of distributed MPC by comparing overall costs for legacy and distributed MPC control strategies.
• Demonstrate the ability of the proposed distributed MPC solution to replace the legacy control in multiple steps.
– In each step, the APC will be implemented on a selected network part only.
– Important for practical application and advanced process control life cycle; standard requirement by process operators.
– Demonstrating the ability of APC to work with some controllers switched to a backup strategy based on the legacy control
• Demonstrate control over wireless network on the lowest control level.
– Robust algorithms assuming communication delays, packet dropouts, etc. will be demonstrated on flow or tank level control with wireless sensors and actuators.
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Benefit Demonstration
• As a baseline, the price of the current PID-based control strategy will be evaluated from 3 days historical process data.
• Two distributed advanced control strategies will be evaluated:
– Distributed MPC with the central coordinator
– Distributed MPC without the central coordinator
– In either case, local MPC controllers will control groups of tanks.
• All strategies will use identical initial tank level settings and demand data.
• Demonstration Scale:– Full model of the Barcelona Water
network• Demonstration Platform
– MATLAB/Simulink
1
2 5
3 4 6
7
1
2 5
3 4 6
7
Coordinated Distributed MPCControllers communicate with coordinator only
+ low number of iterations
Distributed MPCControllers communicate with neighbors only.
+ modularity, robustness
1
2 5
3 4 6
7
1
2 5
3 4 6
7
C12 C345 C67C12 C345 C67 C12 C345 C67
COORDINATOR
1
2 5
3 4 6
7
11
22 55
33 44 66
77
Water network for the demonstration of the different distributedcontrol strategies
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Sequential Replacement of Legacy Control• Replacement of legacy control in
successive steps.• Demonstration will be done on a part
of the network model.• The part of the network is divided
into 3 groups of tanks– At the beginning, the network section
under consideration is controlled by the PID-based legacy control.
– Nominal trajectories are pre-computed for all flows.
• Group #1 is switched to advanced control while the rest is controlled by the legacy control strategy.
• Groups #2 and #3 are sequentially switched from the legacy to the advanced control.
• Simulated communication failures can test switching from the advanced to legacy control used as a back-up.
• Demonstration scale– Part of the network
• Demonstration platforms– Model – Simulink– Backup control and backup/APC switching:
Simulink, using blocks emulating Honeywell Experion DCS
– Advanced Control – Honeywell URT platform communicating with Simulink over the OPC bridge
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Wireless Control
• Applied to the base control layer with fast sampling (1 second)
– Network effects will not show up at the advanced control layer with sampling interval 1 hour.
• Demonstrating Integration of WSN and DCS.
• PID controller will be given, in place of raw measurement, a process value estimated by a network-aware Kalman filter.
– Kalman filter will receive measurement data from the network with time stamps provided by the sensor.
– Kalman filter will further receive time stamps of manipulated variables provided by the actuator, to account for network delays in the MV channel.
• Network delays and data losses will be simulated using network models developed in WP2.
• Demonstration scale– Single flow/tank level controller
• Demonstration platform– Simulink– Real Site
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Distributed MPC
• Local controller controls water level for a group of tanks by defining set-points of internal flows
– Internal flows – between tanks of the same group, controlled by PID controllers at the DCS level
– External flows – between tanks of different groups. Determined by a consensus negotiated between neighboring controllers.
– Set-point for an external flows is imposed by the predefined controller
• The implementation of the local controller allows its use in 2 strategies
– With a global coordinator defining shadow prices of external flows
– Without a global coordinator: shadow prices are defined locally by one of the neighboring controllers
Distributed MPC Controller
Distributed MPC Controller
Demands (DV)Internal Flows (MV)
External Flows (MV)
(Controlled) External Flows Set Points
Communication Network
Tank Levels
Internal Flows Set Points
Global Coordinator
Interface
Neighboring Controllers Interface
External Flows Coordinator Local Optimizer
Local Demands Predictor
Constraints and Prices
coordinated / non-coordinated
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Backup Strategy
• Legacy PID-based solution guarantees operational safety, and a baseline operation.
• Required as a back-up control strategy with advanced control
• Back-up control uses pre-computed nominal flow/level trajectories.
• Flow controllers either– follow nominal flow trajectories– track flow trajectories of the master level
controller.
• Master level controller (one per tank)– Tracks the nominal level trajectory– Typically controls the inflow with largest
capacity for the tank.
• Advanced control (MPC), if available, provides set-points for flow controllers
pump or valve
PID
PID
Level controller
Nominal level trajectory
Flow controller
Tank water level
SP from Distributed MPC Remote CAS
Master Level Controller
CAS
Flow Controller
Nominal flow trajectory
CommunicationNetwork
SW1
SW2
• In the case of a level control on a tank being in the back-up mode due to the communication failure, MPC can still control other tanks
– Manipulated variable in the back-up mode can be treated as a disturbance by MPC
T5.2 Dynamical model of the water network and model decomposition
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Network Model
121 control variables
67 system states (tank volumes)
88 perturbations (water demands)
15 additional constrains (related to the nodes equalities)
Matlab implementation
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Graph Analysis
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Subsystem Decomposition using Graph PartitioningPROPOSED SOLUTION – Graph Partitioning Algorithm
• Novel algorithm for automatic LSS subsytem decomposition based on a graph partitioning approach
• Step 0: Graph representation of the LSS system
• Step 1: Subsystem decompostion based on identifyng loosely coupled subsystems using graph theory
• Step 2: Solution refinement using some auxiliary criteria
PUBLICATIONSPaper submitted to IFAC World Congress 2011 and Journal of Process Control
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Daily forecast
Hourly forecast
Demand Forecast Time Series Model
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Electricity Cost Model
- An electricity cost model that takes into account the price of electricity depending on the day, hour and period of the year has been developed and taken into account in the MPC formulation.
T5.3 Control design for the water network
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1. Energy/Production Costs
2. Operation-safety Costs
3. Stability Costs
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MPC Objective Function Formulation
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Distributed MPC
SOLVED PROBLEM• Design of Distributed MPC for truly large scale
systems
• Class of target systems (Barcelona WN):• Centralized optimization problem impossible to
solve due to high number of variables (~5000) and constraints (~10000)
• Long sampling period (1 hrs) iterative solution with nearly optimal performance
• Two controller types:• WITH Central Coordination – fast coordination,
useful also for large scale optimization on a single computer
• WITHOUT Central Coordination – local controllers coordinate flows between neighbors only (modular architecture)STATE OF THE ART
• Well known methods based on dual decompositions; however, with problematic speed of convergence
• No application of MPC to full-scale water distribution network
• LS system partitioning algorithms for DMPC are missing
Distributed MPC
Coordinated Distributed MPC
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Hierachical Decentralized MPC PROPOSED SOLUTION - Decentralized MPC
• A hierarchy of a local MPC controllers (one per each subsystem) is designed.
• Only one optimization per MPC controller is necessary. Coordination is established thanks to the unidirectional flow of shared variables.
PUBLICATIONSPapers presented at ACC’10, LSS’10 and submitted to IEEE Journal
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Wireless PID Control in Lab Environment (1)
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Wireless PID Control in Lab Environment (2)
0 2 0 0 4 0 0 6 0 0 8 0 0 1 0 0 0 1 2 0 0 1 4 0 00
0 . 2
0 . 4
0 . 6
0 . 8
1
1 . 2
1 . 4T a n k L e v e l
T i m e ( s )
Lev
el (
mm
)
S e t P o i n t
L e v e l
0 1 0 0 2 0 0 3 0 0 4 0 0 5 0 0 6 0 0 7 0 0 8 0 0 9 0 0 1 0 0 00
2
4
6
8
1 0
1 2S a m p l i n g T i m e E S e n z a
S a m p l e s ( s )
Tim
e (s
)
S a m p l i n g T i m e E S e n z a
0 1 0 0 2 0 0 3 0 0 4 0 0 5 0 0 6 0 0 7 0 0 8 0 0 9 0 0 1 0 0 00
5
1 0
1 5
2 0
2 5T i m e R e c e p t i o n M a t l a b
S a m p l e s ( s )
Tim
e (s
)
T i m e R e c e p t i o n M a t l a b
0 1 0 0 2 0 0 3 0 0 4 0 0 5 0 0 6 0 0 7 0 0 8 0 0 9 0 0 1 0 0 00
2 0 0
4 0 0
6 0 0
8 0 0
1 0 0 0T i m e D e l a y
T i m e ( s )
Del
ay (
s)
E S e n z a s a m p l i n g t i m e
M a t l a b r e c e p t i o n T i m e
0 1 0 0 2 0 0 3 0 0 4 0 0 5 0 0 6 0 0 7 0 0 8 0 0 9 0 0 1 0 0 0- 5
0
5
1 0
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2 0T i m e D e l a y d i f e r e n c e
T i m e ( s )
Del
ay d
ifer
ence
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D i f e r e n c e b e t w e e n E S e n z a a n d M a t l a b t i m e s
T5.4 Development of the water demo demonstrator
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Network Simulator
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Simulated volume (blue) compared to real volume (red) for some tanks
2 0 4 0 6 0 8 0 1 0 0 1 2 0
2
3
4
5
6
7x 1 0
4 d 1 0 0 C F E
t i m e ( h )
m3
2 0 4 0 6 0 8 0 1 0 0 1 2 0
2 0 0
3 0 0
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5 0 0
d 1 1 4 S C L
t i m e ( h )
m3
2 0 4 0 6 0 8 0 1 0 0 1 2 0
1 0 0 0
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d 1 1 5 C A S T
t i m e ( h )
m3
2 0 4 0 6 0 8 0 1 0 0 1 2 0
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1 . 5
x 1 04 d 1 3 0 B A R
t i m e ( h )
m3
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2 5 0 0
3 0 0 0
d 1 3 2 C M F
t i m e ( h )
m3
2 0 4 0 6 0 8 0 1 0 0 1 2 0
4 0 0
6 0 0
8 0 0
1 0 0 0d 1 3 5 V I L
t i m e ( h )
m3
2 0 4 0 6 0 8 0 1 0 0 1 2 02 0 0
4 0 0
6 0 0
8 0 0
1 0 0 0
d 1 7 6 B A R s u d
t i m e ( h )
m3
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5 0 0
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2 0 0 0
2 5 0 0
3 0 0 0
d 4 5 0 B E G
t i m e ( h )
m3
2 0 4 0 6 0 8 0 1 0 0 1 2 0
1 0 0 0
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t i m e ( h )m
3
S i m u l a t o r
R e a l d a t aU p p e r l i m i t
S a f e t y l e v e l
Network Simulator Validation
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Interface Simulator/DMPC Controller
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Electrical and Software Interfaces for Wireless Test
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MATLAB Toolbox for E-Senza Wireless Devices
Gra
phica
l Reu
lts
C
ontro
l Pro
cess
Dat
a Ac
quis
ition
Con
figur
atio
n
Port Set-Up
Network
Module
Variables Declaration
Is data OK?
Read Port
no
Check module data source
yes
Store data
PID
Write Port
Plot Data
Acquisition Time end?
END
yes
no
Network Management
Process Controller
Matlab
Real Tank System
Sensor Environment
Data
Esenza Coordinator
SC130
Esenza BlockSB130
AO AI
T5.5 Testing and evaluation
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Centralized MPC Results
• Centralized MPC Control of Barcelona water network has been implemented by means of PLIO tool.
• To test and adjust the MPC controller some different scenarios have been studied. Parameters to take into account in the calibration of the model are:
– Initial and security levels in tanks– Objective function weights: economical, safety and maintenance factors. – Working with different sources operation:
• Llobregat source set at constant flow (Scenario 1)• Fixed sources at real flow (Scenario 2)• Source optimization. The optimizer calculates the flow for each time step
inside the operational limits of each source (Scenario 3)
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Centralized MPC: Scenario 1 (1)
Flow(m3/s)
Case 1 Case 2
Llobregat surface source 3 0
Llobregat underground source 2 2
• Barcelona’s average input flow is about 7.5 m3/s.• In case 1 an important part of the total demand is taken from Llobregat. • In case 2 only a 25% of the total demand is taken from Llobregat. It is expected that
an important part of the network consumption is going to be taken from Ter.• These two scenarios are interesting from the point of view of the behaviour of the
economical cost.
Scenario 1: Llobregat source set at constant flow
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Centralized MPC: Scenario 1 (2)
• Conclusions• It exists a strong and linear dependency between economical cost and the
operation of this two sources.• In order to reduce the total cost it is necessary to maximise the quantity of
water taken from Llobregat.
Electrical cost Water cost Total cost
Day 1 52,42 47,58 100,00
Day 2 46,65 53,35 100,00
Day 3 48,10 51,90 100,00
Day 4 47,57 52,43 100,00
Electrical cost Water cost Total cost
Day 1 -50,27 +91,34 +17,11
Day 2 -47,94 +72,77 +16,47
Day 3 -48,37 +78,27 +17,36
Day 4 -47,67 +71,06 +14,58
Case 1
Case 2
Increase/decrease % in comparison to case 1
2 2.5 3 3.5 4 4.5 5 5.520
30
40
50
60
70
80
Llobregat flow (m3/s)
Elec
tric
al/w
ater
cos
t (%
)
2 2.5 3 3.5 4 4.5 520
30
40
50
60
70
80
Ter flow (m3/s)
Elec
tric
al/w
ater
Cos
t (%
)
Electrical cost regressionWater cost regressionqLl=4qLl=3
Optimised sources case
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Centralized MPC: Scenario 2
Sources flow is imposed by using real data obtained from AGBAR historical database.
It is an interesting case study in order to compare centralised MPC control and current control applied regarding to transportation cost.
It is a previous step before comparing centralised and decentralised MPC control.
Important improvement in electrical cost, which represents between 10% and the 25 % of the real operation cost.
Total cost using MPC control is between 4 and 8 % lower than the real one.
Scenario 2: Sources set at real flow
Current control
MPC
Increase/decrease % in comparison to current control
Electrical cost Water cost Total cost
23/07/2007 33,13 66,87 100,00
24/07/2007 34,66 65,34 100,00
25/07/2007 32,00 68,00 100,00
26/07/2007 31,29 68,71 100,00
Electrical cost Water cost Total cost
23/07/2007 -23,27 +0,00 -7,71
24/07/2007 -10,56 +0,00 -3,66
25/07/2007 -20,61 +0,00 -6,59
26/07/2007 -18,58 +0,00 -5,81
0 2 0 4 0 6 0 8 0 1 0 00
0 . 5
1
1 . 5
2U n d e r g r o u n d s o u r c e s f l o w
t i m e ( h )
flow
(m
3/s)
i S J D S u bi P o u s C a s t
i C a s t e l l d e f e l s 8
i M i n a S e i x
i E s t r e l l a 1 2
i E s t r e l l a 3 4 5 6i E t a p B e s o s
0 2 0 4 0 6 0 8 0 1 0 00
1
2
3
4
5
6S u r f a c e s o u r c e s f l o w
t i m e ( h )
flow
(m
3/s)
i S J D S p f
v A b r e r a
v T e r
0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 9 0 1 0 05
6
7
8
9
1 0
1 1T o t a l i n p u t f l o w
t i m e ( h )
flow
(m
3/s)
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Centralized MPC: Scenario 3 (1)
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In this case electrical and water costs are minimised, so it is expected a higher improvement in the total cost referring to the scenario with fixed sources.
Taking into account results obtained in the first case study (constant fixed flow in Llobregat source) a solution with maximum average flow from Llobregat source is expected.
In the optimization results shown the term that guarantees stability in control elements (pumps and valves) is on.
Underground sources’ water cost is penalized to avoid its over-exploitation.
Scenario 3: Flow optimization
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Centralized MPC: Scenario 3 (2)
Electrical cost Water cost Total cost
23/07/2007 33,13 66,87 100,00
24/07/2007 34,66 65,34 100,00
25/07/2007 32,00 68,00 100,00
26/07/2007 31,29 68,71 100,00
Current control
Electrical cost Water cost Total cost
23/07/2007 18,92 -50,70 -27,63
24/07/2007 14,04 -32,56 -16,41
25/07/2007 26,29 -43,91 -21,45
26/07/2007 26,09 -44,43 -22,36
MPC improvement in comparison to current control case
MPC improvement in comparison to fixed sources to real flow case (Scenario 2)
Electrical cost Water cost Total cost
23/07/2007 54,99 -50,70 -21,59
24/07/2007 27,51 -32,56 -13,23
25/07/2007 59,08 -43,91 -15,91
26/07/2007 54,86 -44,43 -17,57
– Big water cost savings, between 30% and 50 %.– Electrical cost has increased regarding to
current control case ([+18,+27]%) and MPC case with fixed sources ([+27,+60]%).
– Total cost has decreased between 13% and 22 % regarding to MPC results obtained with fixed sources.
– Sources flow distribution is the expected one. Llobregat’s source flow is maximized.