innovative electronic systems for vehicular and nautical applications roberto saletti, sergio...
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Innovative Electronic Systems for Vehicular and Nautical Applications
Roberto Saletti, Sergio Saponara, Luca Fanucci, Federico Baronti, Roberto Roncella, Pierangelo Terreni
Dipartimento Ingegneria dell’Informazione
University of Pisa, Italy
E-mail: [email protected]
APPLEPIES Roma June 11, 2012
APPLEPIES – Roma – June 11, 2012 Roberto Saletti 2
Outline
• Motivations• Electronics for vehicle applications
Embedded systems for automotive applications• Electric and/or hybrid vehicles
– Energy Storage Systems– Battery Management Systems
• Electronic replacement of mechanical subsystems– AMDS (Advanced Mechatronic Door System)
• Electronics for nautical applications Superyacht market segment (Luxury yacht with LOA > 24m)
• Integrated data acquisition systems Innovative sensors for boat and seawater parameter
measurement• Freeboard measurements• Seawater density measurement
APPLEPIES – Roma – June 11, 2012 Roberto Saletti 3
Motivations
• Conference aim and scope “defining the activities, topics, objectives and research areas
of the applications of electronics” “the application domain – which was once considered as a
separate level over the technology – is now a part of the technology itself”
• Show on-going activities in the electronic applications’ research field at the University of Pisa
• Show application systems where “hardware and software are the different faces of the same coin”
• Show examples of applications where electronics is the key factor for progress and improvement
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Vehicular applications
• The most significant improvements in last years vehicular market come from electronics Control
• Combustion control, Emission control, Traction control, Stability control, Drive-by-wire, steer-by-wire, X-by-wire
Safety• Active safety, Multiple Air-bags, Assisted braking systems,
Intelligent seat belts, Parking aid and collision avoidance systems
Info-tainments• Vehicle-infrastructure communication, Traffic info, Navigational
aids and info, Kids and passengers entertainment
• Vehicles contains hundreds of ECUs, communication systems and multiple computer networks
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Trends for present/future vehicles
• Increased environmental sensibility
• More stringent rules and laws for polluting emissions
Electric and/or hybrid vehicles
ZEV (Zero-Emission Vehicle)
• Replacement of mechanical systems with mixed (mechanical/electronics) ones that give unexpected performance with affordable costs
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Electric/hybrid vehicles
• An energy storage systems is mandatory Proper storage of energy Allows energy recovery during braking
• Rechargeable batteries are the solution
• Common rechargeable battery chemistries: Lead acid NiCd NiMH Li-ion Li-polymer Li-Iron-Phosphate (LiFePO4)
…
battery of choice for portable applications:mobile phones, laptops, ecc.
dominant in automotive (engine starter) and industrial applications (power backup and grid-load leveling systems)
current choice for hybrid vehicles
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Comparison of battery energy densities
Source: www.mpoweruk.com
Due to the excellent performance in energy density and power density Lithium chemistry is emerging also in high power applications
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Lithium chemistry
• Very high energy density, no memory effect,very low self-discharge, very high efficiency, etc.
• Very sensitive to overcharge and deep discharge and to exceeding specific temperature range Cell life shortening, …, risk of explosion
• Different technologies: Different choices for electrodes and insulator materials Lots of ongoing researches …
• Battery cells safety is mandatory Here comes Electronics Safety is increased by an electronic management system
(Battery Management System – BMS)
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Battery Management System (BMS)
• Low-level functions: Cell voltage and temperature monitoring Current monitoring Cell balancing Communication with a host device
• High-level functions: Maintain each cell of the battery pack within its safe
operating range Estimate SoC (State-of-Charge) and SoH (State-of-Health) Increase the battery pack lifetime Manage thermal aspects
…and of course very little power consumption(al least when the battery current is zero)
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BMS: hierarchical platform
• Electric vehicle battery (300-400 V) up to 1 kV for distributed energy storage in smart-grids Roughly 100 or more series-connected high-capacity
elementary cells
• Battery pack usually partitioned in modules From 4 to 14 cells per module
• BMS architecture reflects thephysical structure of the battery
Cell
Module
Pack
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BMS: hierarchical platform (cont.)
• PMU (Pack Management Unit)• MMU (Module Management Unit)• CMU (CellMonitoringUnit)• PPS (Pack ProtectionSwitch) • MBS (Module Bypass Switch)
......CMU
MMU
CMU
PMU
...CMU
MMU
CMU
Vehicle Management System• High flexibility and scalability• Redundancy support• Dynamic pack reconfiguration
through the MBS• Module-level active balancing
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BMS: Cell Monitoring Unit
• Benefits of an intelligent cell: Local voltage and temperature measurement Cell identification Cell history (lifetime, cycle number, etc) Second market application
• Very simple design A small 8-bit µC w/ 10-bit ADC Few external components to provide isolated communication with the MMU
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BMS: CMU design example
• CMU implementation with discrete off-the-shelf components
CMU prototype applied to a 31 Ah LiPo cell
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BMS: MMU design example
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MMU: board prototype
AuxCell
Connectorsto the CMUs
Active charge equalizer based on a Buck-Boost Converter with super-capacitor
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BMS: MBS design example
• Isolated gate driving• Very low dead-time• Liquid cooled heatsink
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BMS: MBS design example (cont.)
• Battery pack for a fuel-cell hybrid small van(steady state current up to 160 A)
• ΔT=70 °C &PD
MBS=66W@ Ibattery=160 A
• Little efficiencydegradation
• e.g. N=11Vcell=3.7 V %1
cellcell
2
cell
NV
Ir
INV
Ir
INV
P MBSon
MBSon
MBSD
At maximum load!
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BMS: hierarchical platform prototype
• Hydrogen Fuel Cell Hybrid Electric Vehicle (H2FC-HEV) which is being developed at University of Pisa 14.4 kW hydrogen fuel cell 155 V - 40 Ah LiPo battery pack
M. Ceraolo et al., “Experiences of realisation and test of a fuel-cell based vehicle,” SPEEDAM 2010
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BMS: hierarchical platform prototype
• Module implementation: 11 40 Ah LiPo cells FC-HEV battery built up of 4 modules 11 CMUs 1 MMU 1 MBS
• Electronic system with: Hardware
• 14 microcontrollers• FPGA• Power devices• Hall sensors• Temperature sensors
Software/firmware• 3 level hierarchical applications
– Low level micro firmware– Medium level micro firmware– High level Labview application
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BMS: hierarchical platform prototype
• Module implementation: MMU connected to a PC
by CAN bus LabVIEW app emulates
the PMU Testing of BMS
functionalities Screenshot refers to an
on-going balancing cycle (see the differences in cell voltages)
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Electronic replacement of mechanical parts
• Advanced Mechatronics Door System E-Latch
• Fully electronic vehicle latch• Existing sensors• Electrical motor drive for actuation
Cinched door• Electrically activated door closure
Electrical crystal glass control with anti-pinch control
• A challenge for the stringent automotive specs
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Superyacht nautical market
• Italy is by far the world largest producer of superyachts
• Nautical market has collapsed because of the global financial crisis
• New impulse is expected after the crisis
• New products and applications are expected to come
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Electronics application to Superyacht test
• Superyachts are complex systems embedding hundreds of heterogeneous electronic controlled systems
• Lack of integration and standardization
• Extensive Test & Correction procedure before final delivery to customers
• So far, manual registration of the data displayed on the dashboard, combined with feelings of expert drivers
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Dedicated acquisition system for Ferretti
• Multi-sensor, multi-protocol acquisition system
• Integrated and synchronous acquisition @1 Hz from: Engine subsystems
(CAN SAE-J1939, CANOpen) Navigation subsystem
(Raymarine SeaTalk, NMEA-0183)
Flap and Trim subsystems (Analog, CANOpen, MODBUS TCP/IP)
Custom two-axis wireless inclinometer
• Automatic configuration for hundreds of yacht models
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DAQ features
• Unified user interface for data visualization• System guided automatic test procedure• Test results are stored and compared with references• Remote analysis of the test results
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Useful data
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Innovative sensors for nautical applications
• Freeboards measurements to provide information about the yacht weight and trim Wireless sensor network of magnetostrictive linear
displacement sensors
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Freeboards measurements
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Freeboards measurement results I
Data acquired from different nodes are strictly related
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Freeboards measurement results II
The operator’s weight (90 kg) causes a not negligible error!
≈ 20 mm
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Electronic seawater density meter
• Magnetostrictive displacement sensors to read the immersion of a structure semifloating in seawater
• Immersion depends on seawater density
ρ0
ΔL hs h
wf
ρ>ρ0
Surfacespherical probe
Weighted float
1000 1010 1020995
1000
1005
1010
1015
1020
1025
Glass hydrometer readings (and linear fit )Electronic density meter readings (and linear fit )
Wat
er d
ensi
ty (
g/dm
3 )
Theorical water density at 25°C
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Conclusions
• Overview of research activities at the University of Pisa on the application of Electronics
• Main research fields are Vehicular electronics Nautical applications
• All the examples show a deep interaction between Hardware
• Sensors and data conditioning and conversion• Controllers• Power devices
Software• Microcontroller firmware• Higher level software (C++, Labview, Web applications)
• Knowledge of the application domain is mandatory Electronic engineers are ever more often asked to tackle and solve
multidisciplinary (mechanical, thermal, etc.) issues