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2014-11-11
Technical Paper
2014-32-0071
Christian Schweikert, David Witt, Dirk Schweitzer, Marco Nicolo, Liu Chen
Abstract The market potential for products such as scooters and small motorcycles is already self-sustaining. However, other applications for small engines can be more fragmented with a wide variety of requirements for the engine control unit. Consequently, the engine control unit can be designed to accommodate more features than are necessary for a given application to cover a broader market. The flip side of this approach is to design the engine control unit for a limited application reducing the market size. Neither approach creates a cost efficient product for the producer. It either supplies the market with an electronic control unit that has features not being utilized (wasted costs) or a unit that has limited capabilities reducing the economies of scale (higher costs). When these designs are developed using discrete components these inefficiencies are exacerbated. Integration of these functions at the semiconductor level can mitigate these costs, improve the thermal performance and expand the functional capabilities to include additional vehicular control aspects in the electronic control unit.
2014-10-13
Technical Paper
2014-01-2590
Yuanzhe Zhong, Sahil Sane
Abstract Electronic controls in internal combustion engines require an in-cylinder combustion sensor to produce a feedback signal to the ECU (Engine Control Unit). Recent research indicated that the ion current sensor has many advantages over the pressure transducer, related mainly to lower cost. Modified glow plugs in diesel engines, and fuel injectors in both gasoline and diesel engines can be utilized as ion current sensors without the addition any part or drilling holes in the cylinder head needed for the pressure transducer. Multi sensing fuel injector (MSFI) system is a new technique which instruments the fuel injector with an electric circuit to perform multiple sensing tasks including functioning as an ion sensor in addition to its primary task of delivering the fuel into the cylinder. It is necessary to fundamentally understand MSFI system. In this study the author will firstly explore the influence of piston motion (as one side of variable capacitance) on the ion sensor signal through modeling and simulation, and then look into the origin of the MSFI signal of fuel injection; and finally the author will look at how to analyze MSFI signal to duplicate the injection command profile for on-board diagnostics (OBD).
2014-10-13
Technical Paper
2014-01-2584
Krisada Wannatong, Sompach Kongviwattanakul, Thananchai Tepimonrat, Thanadech Priroon
Abstract End of line test (EOL) of Engine Control Units (ECU) is the process of ECU functions validation before releasing ECUs to the car assembly process. Examples of ECU function that need to be validated are idle control, air path control and faults manager function. To perform EOL, a vehicle and a chassis dynamometer are used to enable control functions validation inside the ECU. However, this poses high operating cost and long setup time. This paper presents the development of Hardware-in-the-Loop (HiL) system, which imitates real vehicle behavior on a chassis dynamometer. The diesel high pressure pump model was developed using an empirical dynamic modeling approach. The engine model was developed using AVL BOOST RT software, an engine cycle simulation modeling approach. The vehicle model was developed using AVL CRUISE software. In order to interface the engine and vehicle models with the ECU, HiL system was implemented. In the new EOL process, the vehicle was operated following the Extra Urban Driving Cycle (EUDC) including short engine idling time.
2014-10-13
Technical Paper
2014-01-2707
Brian C. Kaul, Benjamin J. Lawler, Charles E.A. Finney, Michelle L. Edwards, Robert M. Wagner
Abstract Advances in engine controls and sensor technology are making advanced, direct, high-speed control of engine combustion more feasible. Control of combustion rate and phasing in low-temperature combustion regimes and active control of cyclic variability in dilute SI combustion are being pursued in laboratory environments with high-quality data acquisition systems, using metrics calculated from in-cylinder pressure. In order to implement these advanced combustion controls in production, lower-quality data will need to be tolerated even if indicated pressure sensors become available. This paper examines the effects of several data quality issues, including phase shifting (incorrect TDC location), reduced data resolution, pressure pegging errors, and random noise on calculated combustion metrics that are used for control feedback. Symbolic data analysis is an effective technique for identifying underlying patterns in noisy data, and has been applied to cyclic variability of dilute SI combustion, identifying deterministic effects that underlie the stochastic variations that are present.
2014-10-13
Technical Paper
2014-01-2613
Mario Farrugia, Andrew Briffa, Michael Farrugia
Abstract A conversion to LPG of a SI engine that was originally carbureted gasoline is reported in this work. The conversion was implemented on a 1988 Skoda 120L with a 1174cc rear engine. The conversion to run on Liquefied Petroleum Gas (LPG) was carried out using a programmable Engine Control Unit (ECU) that operated a single point fuel injection system. The LPG used was a commercially available mixture of butane and propane. The fuel injection system was designed to operate with the LPG in the liquid state. A circulating pump was used to maintain availability of LPG in liquid state at the inlet to the fuel injector. This made possible the use of similar fuel injection parts as in a gasoline system. Injection of the fuel in the liquid state provided cooling to the intake air as measured during driving of the vehicle and also on chassis dynamometer runs. Engine power output measured on the chassis dynamometer showed equal power between gasoline and LPG around mid RPM of 2500 RPM with a slight decline (4%) in power of the LPG system at 5000 RPM.
2014-10-13
Technical Paper
2014-01-2894
Boru Jia, Zhengxing Zuo, Huihua Feng, Guohong Tian, A. P. Roskilly
Abstract The free-piston engine generator (FPEG) is a novel type of energy conversion device; it integrates a two stroke combustion engine and a linear electric machine into a single unit. As an alternative to conventional engines, the FPEG is a promising power generation system due to its simplicity and high thermal efficiency and has attracted considerable research interests recently. This paper presents the development for a spark-ignited free-piston engine generator prototype, and the design of major sub-systems is introduced. The electrical linear machine is operated as a motor to start the engine and switched to a generator after successful ignition. Ignition is one of the most crucial problems for the generating process, thus a unique control sub-system to generate ignition signals at the correct ignition timing based on the piston position was completed. Then experiments of the starting process were carried out with the prototype. The results indicate that with a fixed motor force of 110N, the maximum in-cylinder gas pressure can reach 12 bar and the compression ratio can reach 8:1.
2014-09-30
Technical Paper
2014-01-2421
Massimiliano Ruggeri, Carlo Ferraresi, Luca Dariz, Giorgio Malaguti
Abstract Functional safety requirements and solutions are more expensive when it comes to lower cost machines with less power but same functionalities with respect to big machines. The paper will show a real Electronic Control Unit (ECU) design of a machine controller, controlling both engine working point, transmission, and other utilities like PTO, 4WD, brakes and Differential Lock; the ECU was designed in accordance to ISO 25119 regulation, to meet AgPL = C or even D for some functionalities. The unit is a fully redundant electronic control unit with two CAN networks and some special safe state oriented mechanism, that allow the Performance Level C with less software analysis requirements compared with traditional solutions. All safety critical sensors are redounded and singularly diagnosable, all command effects are directly observable and most of commands are directly diagnosable. With a minimum extra-cost the hardware category for the most critical controls was brought to the category 4, thus theoretically allowing the Performance Level D achievement.
2014-09-30
Technical Paper
2014-01-2399
Michael Sprengel, Monika Ivantysynova
Abstract A novel Blended Hydraulic Hybrid transmission architecture is presented in this paper with benefits over conventional designs. This novel configuration combines elements of a hydrostatic transmission, a parallel hybrid, and a selectively connectable high pressure accumulator using passive and actively controlled logic elements. Losses are reduced compared to existing series hybrid transmissions by enabling the units to operate efficiently at pressures below the current high pressure accumulator's pressure. A selective connection to the high pressure accumulator also allows for higher system precharge which increases regenerative braking torque and energy capture with little determent to system efficiency. Finally operating as a hydrostatic transmission increases transmission stiffness (i.e. driver response) and may improve driver feel in certain situations when compared to a conventional series hybrid transmission. To explore the novel blended hybrid architecture six transmissions were modeled and simulated.
2014-09-30
Technical Paper
2014-01-2324
Antoine Delorme, Jason L. Robert, William Eli Hollowell, Andre M. Strobel, Jason T. Krajewski
Abstract In the recent years, Automated Manual Transmissions have become more popular for class 8 heavy trucks. Besides the benefits of smoother gear changes and reduced driver fatigue, AMTs can also greatly reduce fuel consumption by using optimized shifting strategies and advanced controls. The Detroit DT12 AMT demonstrated its ability to save fuel over a standard AMT, due in part to its eCoast feature. eCoast relies on intelligent and advanced electronic controls to safely allow the vehicle to coast on downgrades. While the engine is idling, the drag parasitic energy losses are decreased and the vehicle can fully use its momentum to travel further up and down hill. As one could expect, the type of route profile can greatly affect the fuel savings due to eCoast, since more hilly terrains might offer more opportunities to activate eCoast than flatter roads. In addition, when combined with different vehicle and driving parameters such as vehicle weight and driver desired cruise set speed, the fuel consumption reduction of eCoast is always there, but becomes a more complicated function.
2014-09-28
Technical Paper
2014-01-2527
Gunn Hwang, Axel Freiwald, Hyun-Sik Ahn
Abstract Currently major investments by Tier1 and vehicle manufacturers are made to implement and optimize safety critical automotive systems according to the ISO standard 26262 “Road vehicles functional safety”. The ISO 26262 standard describes methods to detect the safety critical faults of a system designed according to the rules of functional safety, but it does not describe how an actual implementation shall look like. Development of ISO 26262 standard compliant systems concentrates on optimizing and improving cost and performance in a competitive environment. More competitive and practical implementations use fewer additional hardware and software resources for safety control and error detection and have higher performance with less overhead. Microcontrollers already have implemented many safety related hardware functions, so called safety mechanisms to mitigate safety critical risks. Depending on how these safety mechanisms are used, functional safety compliant system can get optimized for cost and performance.
2014-09-28
Technical Paper
2014-01-2524
Chendi Sun, Xiaofei Pei
Abstract This paper presents how hardware-in-the-loop (HIL) simulations have been used for testing during the development of ABS (Anti-lock Braking System). The Labcar system of ETAS is a popular tool for HIL tests. The vehicle model which is built in Matlab/Simulink is downloaded to run in RTPC (Real-time PC). The Labcar software, Integration Platform (IP), can configure boards which is a link between the model and ABS ECU. In this paper, a classical logic threshold control algorithm is adopted in ABS ECU. Through Labcar Experiment Environment (EE) various parameters can be monitored and modified conveniently. The HIL test of ABS ECU is implemented on high or low - adhesion road respectively. The results show that, although response lag exists in the hydraulic braking system, the curves of velocity and pressure in wheel cylinders can be close to those on real road with proper adjustment of control parameters. So HIL simulations are invaluable, when considering the short development time required in the automotive industry.
2014-09-25
Standard
J2399_201409
Adaptive cruise control (ACC) is an enhancement of conventional cruise control systems that allows the ACC-equipped vehicle to follow a forward vehicle at a pre-selected time gap, up to a driver selected speed, by controlling the engine, power train, and/or service brakes. This SAE Standard focuses on specifying the minimum requirements for ACC system operating characteristics and elements of the user interface. This document applies to original equipment and aftermarket ACC systems for passenger vehicles (including motorcycles). This document does not apply to heavy vehicles (GVWR > 10,000 lbs. or 4,536 kg). Furthermore, this document does not address other variations on ACC, such as "stop & go" ACC, that can bring the equipped vehicle to a stop and reaccelerate. Future revisions of this document should consider enhanced versions of ACC, as well as the integration of ACC with Forward Vehicle Collision Warning Systems (FVCWS).
2014-09-16
Technical Paper
2014-01-2213
Noriko Morioka, Hidefumi Saito, Norio Takahashi, Manabu Seta, Hitoshi Oyori
Abstract Electrical power management is a key technology in the AEA (All-Electric Aircraft) system, which manages the supply and demand of the electrical power in the entire aircraft system. However, the AEA system requires more than electrical power management alone. Adequate thermal management is also required, because the heat generated by aircraft systems and components increases with progressive system electrification, despite limited heat-sink capability in the aircraft. Since heat dissipation from power electronics such as electric motors, motor controllers and rectifiers, which are widely introduced into the AEA, becomes a key issue, an efficient cooling system architecture should be considered along with the AEA system concept. The more-electric architecture for the aircraft has been developed; mainly targeting reduced fuel burn and CO2 emissions from the aircraft, as well as leveraging ease of maintenance with electric/electronic components. The AEA should pursue more efficient and eco-friendlier systems, which are easier to maintain than those of conventional aircraft/MEA (More-Electric Aircraft), to enhance benefits for passengers and operators.
2014-09-16
Technical Paper
2014-01-2156
Arthur V. Radun
Abstract There is a continuing need to simulate power electronic circuits that include magnetic components. It is necessary to determine the interaction of the magnetic component with the rest of the power electronic system so that a dynamic circuit model of the magnetic components including material saturation and iron losses is required. Also, the magnetic component model must be valid when the magnetic component's excitation is not sinusoidal. A dynamic magnetic circuit model derived from Maxwell's equations along with useful theorems for building circuit models from the structure of the magnetic device is reviewed. The developed circuit models are general including magnetic saturation and iron losses. Simulation results for a DC/DC converter employing a conventional gapped inductor and a gapped coupled inductor are presented.
2014-09-16
Technical Paper
2014-01-2181
Christopher Ian Hill, Chris Gerada, Paolo Giangrande, Serhiy Bozhko
Abstract This paper presents the initial development of a Modelica Library for Electro-Mechanical Actuator system analysis. At present two main system components are described, these are the Power Electronic Converter and Electric Machine, although further components will be added. These models provide the user with the ability to simulate Electric Machine and Power Electronic Converter systems including physical effects, losses and fault conditions. Established modelling programs such as Saber and MATLAB SimPowerSytems are often unable to provide all the aspects required to accurately simulate real systems in an easy to use, flexible manner. Therefore this paper shows how Modelica has been used to create versatile models able to simulate many practical aspects such as Power Electronic Converter losses and Power Electronic Converter faults, Electric Machine losses and Electric Machine faults. Examples are included in order to demonstrate the use of these models within a variety of systems including an Electro-Mechanical Actuator.
2014-09-16
Technical Paper
2014-01-2186
Neno Novakovic
Abstract Since the early 1970s, when microprocessors became commercially available, they quickly became a common part of all aircraft control and indication systems. With an ever-increasing number of microprocessor-based airborne applications, safety regulations and software standards like RTCA DO-178 evolved, demanding rigorous requirements and processes for software development, testing, life cycle, and certification. Over the years, as development of aerospace software applications increased, engineering costs of development and product certification costs exponentially increased, having a significant impact on the market. Landing Gear Actuation system is one of many aircraft systems whose control functions are based on microprocessors and software application. Considering that Landing Gear Actuation control algorithm can be defined in a form of the State Machine, this article intends to demonstrate that such controller can be realized as wired logic hardware, without software implementation.
2014-09-16
Technical Paper
2014-01-2176
Niloofar Rashidi Mehrabadi, Bo Wen, Rolando Burgos, Dushan Boroyevich, Chris Roy
Abstract The development of the concepts, terminology and methodology of verification and validation is based on practical issues, not the philosophy of science. Different communities have tried to improve the existing terminology to one which is more comprehensible in their own field of study. All definitions follow the same concept, but they have been defined in a way to be most applicable to a specific field of study. This paper proposes the Verification, Validation, and Uncertainty Quantification (VV&UQ) framework applicable to power electronic systems. Although the steps are similar to the VV&UQ frameworks' steps from other societies, this framework is more efficient as a result of the new arrangement of the steps which makes this procedure more comprehensible. This new arrangement gives this procedure the capability of improving the model in the most efficient way. Since the main goal of the VV&UQ process is to quantitatively assess the confidence in modeling and simulation, the second part of this paper focuses on uncertainty quantification.
2014-09-16
Technical Paper
2014-01-2117
Michael L. Zierolf, Thomas Brinson, Andrew Fleming
Abstract Recent emphasis on optimization of engine technologies with ancillary subsystems such as power and thermal management has created a need for integrated system modeling. These systems are coupled such that federated design methods may not lead to the most synergetic solution. Obtaining an optimal design is often contingent on developing an integrated model. Integrated models, however, can involve combining complex simulation platforms into a single system of systems, which can present many challenges. Model organization and configuration control become increasingly important when orchestrating various models into a single simulation. Additionally, it is important to understand such details as the interface between models and signal routing to ensure the integrated behavior is not contaminated or biased. This paper will present some key learnings for model integration to help alleviate some of the challenges with system-based modeling.
2014-09-16
Technical Paper
2014-01-2139
Serhiy Bozhko, Seang Shen Yeoh, Fei Gao, Tao Yang, Christopher Hill
Abstract The paper reports the control design for an aircraft electric starter-generator system based-on high-speed permanent magnet machine operated in a flux-weakening mode and controlled by an active front-end rectifier. The proposed system utilizes advances of modern power electronics allowing the use of novel machine types and the introduction of controlled power electronics into the main path of energy flow. The paper focuses on control design for such system and includes development of flux weakening control of high-speed permanent magnet machine and droop control of the system output dc-link current. The achieved analytical design results and the expected system performance are confirmed by time-domain simulations.
2014-09-16
Technical Paper
2014-01-2113
Fei Gao, Serhiy Bozhko, Greg Asher
Abstract Stability is a great concern for the Electrical Power System (EPS) in the More Electric Aircraft (MEA). It is known that tightly controlled power electronic converters and motor drives may behave as constant power loads (CPLs) which may produce oscillations and cause instability. The paper investigates the stability boundaries for dc multi-source EPS under different power sharing strategies. For each possible strategy the corresponding reduced-order models are derived. The impedance criterion is then applied to study the EPS stability margins and investigates how these margins are influenced by different parameters, such as main bus capacitance, generator/converter control dynamics, cabling arrangements etc. These results are also illustrated by the root contours of reduced-order EPS models. Theoretical results achieved in the paper are confirmed by the time-domain simulations.
2014-09-16
Technical Paper
2014-01-2115
Brian C. Raczkowski, Benjamin Loop, Jason Wells, Eric Walters, Oleg Wasynczuk, Sean Field, Jason Gousy
Abstract Future more electric aircraft (MEA) architectures that improve electrical power system's (EPS's) source and load utilization will require advance stability analysis capabilities. Systems are becoming more complex with bidirectional flows from power regeneration, multiple sources per channel and higher peak to average power ratios. Unknown load profiles with large transients complicate common stability analysis techniques. Advancements in analysis are critical for providing useful feedback to the system integrator and designers of multi-source, multi-load power systems. Overall, a framework for evaluating stability with large displacement events has been developed. Within this framework, voltage transient bounds are obtained by identifying the worst case load profile. The results can be used by system designers or integrators to provide specifications or limits to suppliers. Subsystem suppliers can test and evaluate their design prior to integration and hardware development. By identifying concerns during the design phase, a more streamlined approach to hardware development can save on rework, integration delays and cost.
2014-09-16
Technical Paper
2014-01-2111
Shweta Sanjeev, Goutham Selvaraj, Patrick Franks, Kaushik Rajashekara
Abstract The transition towards More Electric Aircraft (MEA) architectures has challenges relating to integration of power electronics with the starter generator system for on-engine application. To efficiently operate the power electronics in the hostile engine environment at high switching frequency and for better thermal management, use of silicon carbide (SiC) power devices for a bi-directional power converter is examined. In this paper, development of a 50 kVA bi-directional converter operating at an ambient temperature of about 2000C is presented. The design and operation of the converter with details of control algorithm implementation and cooling chamber design are also discussed.
2014-09-16
Technical Paper
2014-01-2104
Jon Zumberge, John Mersch
Cost and performance requirements are driving military and commercial systems to highly integrated, optimized systems which require more sophisticated, highly complex controls. To realize benefits and make confident decisions, the validation of both plant and control models becomes critical. To quickly develop controls for these systems, it is beneficial to develop models and determine the uncertainty of those models so as to predict performance and stability. A process of model validation for a boost circuit based on acceptance sampling is presented here. The validation process described in this paper includes the steps of defining requirements, performing a screening and exploration of the system, completing a system and parameter identification, and finally executing a validation test. To minimize the cost of experimentation and simulation, design of experiments is used extensively to limit the amount of data taken without losing information. One key contribution in this paper is the use of tolerance intervals as an estimation of model accuracy.
2014-09-16
Technical Paper
2014-01-2120
Jennifer C. Shaw, Patrick Norman, Stuart Galloway, Graeme Burt
Abstract Radical new electrically propelled aircraft are being considered to meet strict future performance goals. One concept design proposed is a Turboelectric Distributed Propulsion (TeDP) aircraft that utilises a number of electrically driven propulsors. Such concepts place a new and significant reliance on an aircraft's electrical system for safe and efficient flight. Accordingly, in addition to providing certainty that supply reliability targets are being met, a contingency analysis, evaluating the probability of component failure within the electrical network and the impact of that failure upon the available thrust must also be undertaken for architecture designs. Solutions that meet specified thrust requirements at a minimum associated weight are desired as these will likely achieve the greatest performance against the proposed emissions targets. This paper presents a Fault Tree Analysis (FTA) based design approach for the electrical system and thrust reliability analysis of TeDP aircraft architectures.
2014-09-16
Technical Paper
2014-01-2141
Christine Ross, Michael Armstrong, Mark Blackwelder, Catherine Jones, Patrick Norman, Steven Fletcher
Abstract The Turboelectric Distributed Propulsion (TeDP) concept uses gas turbine engines as prime movers for generators whose electrical power is used to drive motors and propulsors. For this NASA N3-X study, the motors, generators, and DC transmission lines are superconducting, and the power electronics and circuit breakers are cryogenic to maximize efficiency and increase power density of all associated components. Some of the protection challenges of a superconducting DC network are discussed such as low natural damping, superconducting and quenched states, and fast fault response time. For a given TeDP electrical system architecture with fixed power ratings, solid-state circuit breakers combined with superconducting fault-current limiters are examined with current-source control to limit and interrupt the fault current. To estimate the protection system weight and losses, scalable models of cryogenic bidirectional current-source converters, cryogenic bidirectional IGBT solid-state circuit breakers (CBs), and resistive-type superconducting fault current limiters (SFCLs) are developed to assess how the weight and losses of these components vary as a function of nominal voltage and current and fault current ratings.
2014-09-16
Technical Paper
2014-01-2194
Ralf Cremer, Alfred Engler
Abstract The application of power electronics in aircraft is increasing in the latest aircraft developments. This contribution focuses on the recent advances of activities at Liebherr-Elektronik GmbH linked to power electronics: active power filter based on fast silicon carbide switches, open box design for unpressurized area, light weight housing, EMC management, partial discharge detection and mitigation, arc-fault detection and standardized innovative power cores with optimized sensors. These topics are derived from a roadmap based on beforehand identified key drivers. These key drivers will enable the future More Electric Aircraft (MEA) by focusing on weight, reliability and cost. New technologies as Silicon Carbide (SiC) and advanced integration will support this strategy.
2014-09-09
Standard
J917_201409
This SAE Standard covers dimensions, performance parameters and nomenclature of a push-pull control cable used in inboard marine throttle and shift applications.
2014-08-21
WIP Standard
AS24000A
No scope available.
2014-08-21
Standard
J1222_201408
This SAE Recommended Practice provides minimum requirements and performance criteria for devices to prevent runaway snowmobiles due to malfunction of the speed control system.
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