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Off-Road Fuel Cell Vehicle Analysis and Development with a Model-Based Design Approach

AVL Powertrain UK-Tom Kigezi, Bill Insup Kim, Tommi Jokela, Bo Gao
  • Technical Paper
  • 2020-01-1170
To be published on 2020-04-14 by SAE International in United States
Fuel cell and battery electric powertrains are maturing zero-emission technologies expected to complement each other in the future. At present, battery electric powertrains have emerged competitive for urban light-duty transportation while fuel cell powertrains have emerged competitive in heavy-duty commercial transportation, alongside conventional internal combustion engine propulsion. This paper assesses the benefit for fuel cell powertrains in off-road vehicles, taking into account current and target industry data for the various powertrain components. Specific emphasis is placed on three important aspects, namely driving range, vehicle weight, and vehicle cost. Additionally, owing to the increased performance demands of off-road vehicles such as high gradeability and payload capacity, the paper evaluates the merits of a two-speed transmission in comparison to a single speed transmission under drive cycle and performance testing scenarios. A detailed fuel cell model is adopted and validated with real vehicle test data, also from which a highly scalable energy management system is systematically developed. This work adds to a growing industry effort towards zero-emission electrification of off-road vehicles.
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Combined Sizing and EMS Optimization of Fuel-Cell Hybrid Powertrains for Commercial Vehicles

AVL Powertrain UK Ltd.-Tommi Jokela, Athanasios Iraklis, Bill Kim, Bo Gao
Published 2019-04-02 by SAE International in United States
During the last years, fuel-cell-based powertrains have been attracting a lot of attention from commercial vehicle manufacturers for reducing vehicle-related Greenhouse Gas (GHG) emissions. Compared to Battery-Electric Vehicles (BEV), fuel-cell-based powertrains has the strong advantage of dealing with range-anxiety, which is crucial for commercial vehicle with high duty-cycle energy requirements. Amongst the different fuel-cell types, Proton Exchange Membrane Fuel-Cells (PEMFC) have the greatest potential for utilization in automotive applications, due to their relatively high technical readiness, market availability and utilization of hydrogen (H2) fuel. In addition, Solid Oxide Fuel-Cells (SOFC) show good potential due to existing re-fueling infrastructure for light hydrocarbon fuels or heavier hydrocarbon fuels (e.g. diesel). This study focuses on the application of both PEMFCs and diesel-fueled SOFCs in Fuel-Cell Hybrid Electric Vehicle (FCHEV) architectures for commercial vehicles. Delivery vans in the 2.5 t-3.5 t weight range, coach buses and 3-axle tractor-type long-haul trucks are considered energy-driven types and highly suitable for fuel-cell systems, which offer high energy density values. Due to the high number of vehicle application types and system configurations, and…
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Virtual Test Design and Automated Analysis of Lane Keeping Assistance Systems in Accordance with Euro NCAP Test Protocols

AVL Powertrain UK-Jonathan Gibb, Kacper Bierzanowski, Stuart Rowell, Bo Gao
Cranfield University-Michael Holland, Chen Lv, Dongpu Cao
Published 2017-03-28 by SAE International in United States
This paper outlines the procedure used to assess the performance of a Lane Keeping Assistance System (LKAS) in a virtual test environment using the newly developed Euro NCAP Lane Support Systems (LSS) Test Protocol, version 1.0, November 2015 [1]. A tool has also been developed to automate the testing and analysis of this test. The Euro NCAP LSS Test defines ten test paths for left lane departures and ten for right lane departures that must be followed by the vehicle before the LKAS activates. Each path must be followed to within a specific tolerance. The vehicle control inputs required to follow the test path are calculated. These tests are then run concurrently in the virtual environment by combining two different software packages. Important vehicle variables are recorded and processed, and a pass/fail status is assigned to each test based on these values automatically. Any vehicle with a LKAS, and a validated parameter set can therefore be tested and analysed automatically using this testing tool. Automated testing and analysis of a LKAS ensures reduced testing time,…
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Driving Style Identification Algorithm with Real-World Data Based on Statistical Approach

AVL Powertrain-Tarek Ouali, Nirav Shah, Bill Kim, David Fuente, Bo Gao
Published 2016-04-05 by SAE International in United States
This paper introduces a new method for driving style identification based on vehicle communication signals. The purpose of this method is to classify a trip, driven in a vehicle, into three driving style categories: calm, normal or aggressive. The trip is classified based on the vehicle class, the type of road it was driven on (urban, rural or motorway) and different types of driving events (launch, accelerating and braking). A representative set of parameters, selected to take into consideration every part of the driver-vehicle interaction, is associated to each of these events. Due to the usage of communication signals, influence factors, other than vehicle speed and acceleration (e.g. steering angle or pedals position), can be considered to determine the level of aggressiveness on the trip. The conversion of the parameters from physical values to dimensionless score is based on conversion maps that consider the road and vehicle types. These maps have been defined from a representative set of subjectively-rated test trips. The method used to define these maps is described as well. The correlation between…
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Black Box Dynamic Modeling of a Gasoline Engine for Constrained Model-Based Fuel Economy Optimization

AVL Powertrain UK, Ltd.-Ke Fang, David Fuente, Bo Gao
Univ of Liverpool-Andrew Shenton
Published 2015-04-14 by SAE International in United States
New environmental legislation on emission and fuel efficiency targets increasingly requires good transient engine performance and this in turn means that the previously acceptable static engine calibration and control methodologies based on steady-state testing must be re-placed by dynamical optimization using dynamical models. Although many advances have been made in predictive models for internal combustion engines, the phenomena involved are so many, complex and nonlinear that dynamical black-box models typically employing neural network structures must be determined from system identification through experimental testing. Such identified dynamical models are required to provide high accuracy multiple step-ahead predictions of emissions but must accordingly also be compactly implementable for speed and memory to allow for the required large scale optimization involving possibly many thousands of iterations.This paper presents a novel methodology of using black box modeling techniques to build compact efficiently implementable nonlinear dynamic engine models with high predictive accuracy in the form of Neural Network and polynomial equations. The black box models obtained are shown to be efficient for state-of-the-art model-based fuel economy dynamical optimization with emission…
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Analysis of Diesel Engine In-Cylinder Air-Fuel Mixing with Homogeneity Factor: Combined Effects of Pilot Injection Strategies and Air Motion

SAE International Journal of Engines

AVL Powertrain Ltd-Matthias Wellers
AVL Powertrain UK Ltd-Bo Gao
  • Journal Article
  • 2014-01-9052
Published 2014-10-01 by SAE International in United States
With a view to understanding the air-fuel mixing behavior and the effects of the mixture quality on the emissions formation and engine performance, a new quantitative factor of the in-cylinder air-fuel homogeneity named Homogeneity Factor (HF) has been developed. Its characteristics under various injection conditions and air swirl motions within the cylinder have been investigated with CFD simulation. The results have shown that air-fuel homogeneity is essentially affected by the spatial and temporal fuel distribution within the combustion chamber. Higher injection pressure, longer dwell time and increased pilot fuel quantities can contribute to better mixing quality resulting in increased HF and optimum engine performance with low fuel consumption and soot emissions. With regard to the in-cylinder air motion, increasing swirl ratio enhances the air-fuel mixing quality which has been reflected in the variation of the HF. As a result, increased in-cylinder pressure and temperature caused by the optimized air-fuel mixing improved the combustion efficiency.
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Diesel Engine Combustion Optimization for Bio-Diesel Blends Using Taguchi and ANOVA Statistical Methods

AVL Powertrain UK Ltd-Bo Gao, Michail Soumelidis
David Lemon Consultants-David Lemon
Published 2013-09-08 by SAE International in United States
Diesel engine emissions are directly influenced by the air fuel mixture within the cylinder chamber. Increasing concern over the environment impacts of the exhaust pollutants has enforced the setting of emissions legislation since the 1960s. In the last decades emissions legislations have become stricter which resulted to the introduction of multiple injection strategies and exhaust gas recirculation (EGR) in the cylinder in order to abate emissions produced. In this study, the effect of injection rate for double in-cylinder injection in combination with various EGR and bio-diesel fuel rates has been studied using CFD simulations. Taguchi orthogonal arrays have been used for reducing the number of simulations for possible combinations of different rates of injection quantities, EGR composition and bio-diesel quantities. Oneway analysis of variance technique (ANOVA) has been used to estimate the importance of the above factors to the emissions output and performance of the engine. Results showed that using statistical methods, the optimum parameters can be found for reducing the emissions output of the engine without reducing the IMEP. NOx and soot emissions for…
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Approach of Debugging Control Laws of ABS Combined with Hardware-in-the-Loop Simulation and Road Experiment

State Key Laboratory of Automotive Safety and Energy, Tsinghua University-Huiyi Wang, Bo Gao, Jian Song
Published 2001-11-12 by SAE International in United States
Anti-lock Braking System (ABS) is an important control system that can improve the automotive performance, reliability and safety obviously. Hardware-in-the-loop Simulation (HILS) testing is a promising method to assistant design automotive electronics system. In the State Key Laboratory of Automotive Safety and Energy, a HILS system was established to assistant design ABS. The HILS system is composed of a hydraulic control unit of ABS, a normal brake system, a commercial personal computer, a data acquisition card, and several signal-conditioning modules. Powerful software was programmed to perform managing input and output signals, solving 7-freedom and 15-freedom vehicle models, and acquiring response signals of the brake system.Based on the simulations of HILS system, the road experiments with the same conditions of ABS are very necessary and important. In this method, the combination of HILS and road experiment rapidly reduce the cycle of design and debugging the control laws of ABS in automobile.
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