Magneti Marelli Introduces New ECU for MultiAir System

opening management. In this way, itbecomes possible to increase thetorque at partial loads, namely byreducing the gas reflow from the in-take valve, typically found in multi-valve engines.This produces a minimum of 10 per-cent more power, 15 percent moretorque – especially at low enginespeed – and a minimum of 10 percentreduction in fuel consumption.

ECU – new functionality for MultiAirFor the MultiAir system, MagnetiMarelli Powertrain has designed anddeveloped a new ECU based on a32-bit Freescale microcontroller of theMPC5500 family. The ECU managesall engine functions and system com-ponents (including valves), resultingin optimized efficiency, power, andemissions. The ECU is equipped withseveral power drivers and customized

components designed to MagnetiMarelli technical specifications. Magneti Marelli has developed andintegrated a dedicated softwarearchitecture by partitioning the soft-ware into different layers (from HALto application software). This makesthe software components easy tointegrate, test, and calibrate, whileoffering ready reusability.

Most segments of the software com-ponents have been implemented bymeans of model-based technology.The program code has been directlygenerated on the basis of MATLAB®/Simulink® models, resulting in dra-matically reduced software develop-ment times, immediate adaptation ofcontrol strategies, and a robust code.

The ECUs used in development werebased on the aforementioned Free-

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By Alessandro Palazzi and Roberto Valacca, Magneti Marelli S.p.A., and Arnold Mayr, ETAS

ETAS supports ECU software development process

Engine cylinders are traditionally charged through the intake valves, with work cycles controlled by the

rotating camshaft. The main drawbacks of this system are loss of energy as well as restricted options

for adapting to changing driving conditions. “MultiAir”, patented by Fiat Powertrain Technologies

(FPT), is the new technology of dynamic air and combustion control, independent for each cylinder as

well as for each stroke, resulting in more power, reduced fuel consumption, and reduced emissions.

MultiAir defines a new, integratedair intake management system thatuses electrohydraulic actuators. Thelift of the mechanical intake valveis controlled by a high-pressure oilchamber. An electronic control unit(ECU) regulates the oil volume in thechamber by means of a solenoidvalve. With this technology, the en-gine can be adapted very flexiblyto changing requirements.

A real innovationThe solenoid valve loosely “connects”to the intake valve profile of the cam.Upon closing the solenoid valve, theintake valve follows the cam profile.When opening the solenoid valvecompletely, the oil flows out into asecondary chamber. The intake valvecloses completely. In this way, an infinite number ofvalve diagram states may be realized

independently for each cylinder, with-out pressure regulation in the intakesystem.

In the MultiAir engine, every singlecylinder is regulated directly by theVariable Valve Actuator (VVA). Never-theless, the intake pressure is con-trolled by the throttle body to man-age some dedicated functions thatrequire a defined pressure drop (i.e.,through the canister purge valve).The main goal of the engine controlstrategy is to maximize efficiency,minimize pumping losses, and toprovide a more efficient combustion.These objectives are achieved bytaking advantage of different valveopenings:One, early control of valve closingwith respect to the mechanical meansprovided by the cam profile. In thismode, the partial air flow into the

cylinder minimizes the fluid-dynamiclosses compared to an intake mani-fold with a throttle body, as in tra-ditional engines. This mode is usedat medium and low torques.Two, late control of valve opening re-duces the valve lift in order to producea strong turbulence inside the cylinderto optimize the mixture of air andgasoline. This so-called “MultiLift”mode is used at engine startup forcombustion control optimization.

Multiple advantagesThe MultiAir technology facilitatescharging each cylinder individually.The cam profiles can be designedwithout any compromises. The in-take system of the engine can bemaximized towards a power increase. The VVA allows the definition, bymeans of electronics, of different camprofiles with the appropriate valve

High pressure oil chamber

CamPiston

Intake Valve

Solenoid Valve

Modified Marelli MultiAir system.

Marelli MultiAir ECU.

control system development, and willalso serve as a facility for customertraining seminars and workshops re-lated to the same area of endeavor.

The facility features the ETAS auto-motive ECU development environ-ment: Function development – usingrapid prototyping, automatic targetcode generation; testing and valida-tion – using high-performance real-time simulation of vehicle and en-vironment; as well as calibration.Equipped with a complete set of ETASfunction modules, the joint lab willbe recognized as the most completeECU software development environ-ment in China.

47U N I V E R S I T Y C O O P E R AT I O N

Joint Lab

By Jasmine Zhang, ETAS

ETAS China joins hands with Shanghai Jiao Tong University

In November 2009, ETAS China was awarded a million Yuan cooperation contract with Shanghai

Jiao Tong University (SJTU). Under the agreement, ETAS will provide its entire product portfolio

with a view to establishing a comprehensive tool chain that encompasses the entire Lifecycle Process

Model (V-Model), including function development, software development, testing, validation, ECU

calibration, and diagnostics.

Moreover, as part of the recentlyawarded State Engineering Labora-tory of Automotive Electronics atSJTU, a joint laboratory for auto-motive control system engineeringwill be set up in the near future byboth parties. ETAS is thus makinganother powerful contribution to theeducation and development of theautomotive industry in China.

The National Engineering Laboratoryfor Automotive Electronic ControlTechnology is a key industrializationproject approved by the NationalDevelopment and Reform Commis-sion in September 2008. As a newlyestablished scientific and technolog-ical innovation platform and highon the list of the long-term plan ofthe national science and technologyinnovation system, the National En-gineering Laboratory for AutomotiveElectronic Control Technology is the

only domestic laboratory for theautomotive electronics industry witha new, 45 million Yuan Research &Development department and anarea of 10,000 square meters. The labwill become the R&D and techno-logy transfer center for China’s auto-motive electronics industry core tech-nologies, general key technologies,and engineering applications, and animportant base for personnel trainingand international exchanges.

The ETAS-SJTU Joint AutomotiveControl System Engineering Labora-tory established by both parties is anorganization dedicated to researchwork for projects of mutual interest.It also serves as a dedicated facility forconducting customer events relatedto automotive control systems. Thejoint lab will mainly focus on inves-tigating and promoting advancedtechnologies related to automotive

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scale microcontroller, mounted inthe “Chip Scale Package“ with the“VertiCal Base Board“. These ECUswere fitted with a parallel ETKV1.0 tointerface with a variety of ETAS tools.

Tools used in the processThe development of software com-ponents was supported by theINTECRIO rapid prototyping soft-ware, together with the ES1000 andES910 rapid prototyping hardware,which facilitated the execution andtesting of software models beforetheir integration into the real ECUsoftware.INCA has mainly been used to de-velop and manage calibration data ofall software components. Thanks tothe wide range of INCA function-alities, its versatility and simplicity ofuse, the ECU development wascarried out quickly and successfullyin all of its phases. Considering the huge number of vari-ables measurable through the ETK,and the efficient calibration datamanagement provided by INCA, eachof the development phases wasaccelerated enormously.

INCA was deployed in all typical areaswhere calibration data needed to beadapted or modified. For example, on the bench with theECU connected to the HiL system, withan engine model running, along withall system loads; or at the engine testbed, connected to the ECU throughINCA’s standard ASAP3 interface. Inthis application, measured variablesand calibration data were transferredby INCA to perform automated cali-bration of control strategies as wellas the verification of ECU behavior inconjunction with a real engine. Another application for INCA wasdirectly in the vehicle, together withmeasurement modules – ES610,ES620, ES650 among them – for theacquisition and measurement ofanalog signals and temperatures. Fordedicated tasks, e.g., the calibrationof the air pressure predictor model,INCA’s powerful MATLAB® interface(INCA-MIP) was the ideal choice. Inthese special use cases, some repeat-able calibration time histories werecreated in MATLAB® and executedrepeatedly while simultaneouslymeasuring a large number of vari-

ables. INCA was fundamental notonly for calibration activities but alsoduring many phases of softwarecomponent validation. Several INCAexperiments were used in conjunctionwith the ETAS ES715 Drive Recorder.Thanks to its large memory capacityand its automated acquisition func-tionalities, the ES715 permitted theexecution of measurements of ex-treme duration directly onboard thetest vehicles.

MultiAir vehiclesThe 4-cylinder MultiAir system, con-sidered by the Fiat Group as the newreference system for gasoline engines,is already in production on the AlfaMiTo and the new Fiat Punto Evo.It will be used with a wide number ofother vehicles of the Fiat Group, suchas Fiat Bravo, Lancia Delta, and thenew Alfa Giulietta. MultiAir is alsoslated for use in the 2-cylinder ver-sions of the upcoming Fiat 500 aswell as in the new Panda and LanciaYpsilon. The MultiAir 2-cylinder engineis intended to be introduced to allremaining small cars of the FiatGroup.

THE CHALLENGEEngine cylinders are traditionally charged through the intakevalves, with work cycles controlled by camshaft rotation. The main drawbacks of this system are loss of energy as well as restricted options for adapting to changing driving con-ditions.

THE SOLUTIONMultiAir is the designation for the new technology of dynamicair and combustion control. Magneti Marelli has developed a new ECU for the MultiAir system. ETAS supported the ECUsoftware development process by providing its tools, e.g., ETK, ES1000, ES910, ES715, INCA, and INTECRIO, along withvarious measurement modules.

THE BENEF ITThe use of the MultiAir system produces a minimum of 10 percent power increase, 15 percent more torque – espe-cially at low engine speed – and a minimum of 10 percentreduction in fuel consumption.

Alfa MiTo.