Your Selections

Hybrid electric vehicles
Show Only


File Formats

Content Types











NVH benefit of the Frunk

Autoneum Management AG-Federico Di Marco, Flavio Pezzani, Andreas Daving, Luca Mazzarella
  • Technical Paper
  • 2019-01-1456
To be published on 2019-06-05 by SAE International in United States
Due to the increasing number of battery electric vehicles (BEVs), the engineering fields regarding driving comfort and NVH issues are becoming more and more challenging: many new factors affect the development of BEVs NVH package. The noise sources related to the powertrain are different from the traditional ones of internal combustion engines, for instance due to the presence of tonal components, strong harmonics and potential whining noise. To satisfy NVH specifications and the need for lightweight solutions to increase driving range, it is important to mask as much as possible the noise coming from the engine bay with materials both lightweight and acoustically performing. Moreover, for electric vehicles new interesting solutions are possible with the introduction of new components, that do not find room under the hood of ICE or hybrid vehicles. These components, if properly designed, could lead to non-negligible NVH benefits. The present paper reports the NVH effects of one of these new components, the frunk, a small compartment inside the engine bay, functionally similar to the trunk. In this paper, the design-by-simulation…

Target Setting Process for Hybrid Electric Drives Using TPA, Jury Studies, and Torque Management

FCA US LLC-Vinod Singh, Anil Charan
  • Technical Paper
  • 2019-01-1453
To be published on 2019-06-05 by SAE International in United States
The idea of improved efficiency without compromising the “fun to drive” aspect has renewed the auto industry’s interest toward electrification and hybridization. Electric drives benefit from having multiple gear ratios which can use advantageous operating set points thus increasing range. Hybrid vehicles benefit significantly from frequent decelerations and stopping as is experienced in city driving conditions. To recuperate as much energy as possible, deceleration is done at high torque. This presents an interesting but serious sound quality issue in the form of highly tonal whine harmonics of rapidly changing gears that do not track with vehicle speed thus being objectionable to the vehicle occupants. This paper presents an NVH target setting process for a hybrid electric transmission being integrated into two existing vehicles, one belonging to the premium segment and another aimed at enthusiasts with off-road applications. The demand for power has shifted from mechanical domain into electrical domain, and as such, the solution to electric drive NVH issues also lies partly, in the way these drive systems are calibrated. A time-domain Transfer Path Analysis…

Integrated Multi-Physics Simulation for Full-Vehicle Low Frequency NVH Optimization in HEVs

Ford Motor Co., Ltd.-Jack S.P. Liu
Gamma Technologies LLC-Llorenc Gomez, Jonathan Zeman
  • Technical Paper
  • 2019-01-1455
To be published on 2019-06-05 by SAE International in United States
The recent automotive industry trend towards electrification has created new challenges for NVH engineers. These challenges stem from new powertrain architectures and their complex interactions, the governing control strategies which attempt to optimize energy management, and new unmasked sources of excitation. Additionally, vehicle manufacturers are attempting to reduce hardware testing in order to rapidly satisfy increasing production demand and to minimize its costs. Hence, to meet the above mentioned challenges up front in the development process of Hybrid Electrical Vehicles (HEVs) while balancing competing design objectives of drivability, durability and NVH, a simulation-led design and optimization is required. NVH problems are often the result of mechanisms that originate through complex interactions between different physical domains (flow, electromagnetic, structural/mechanical, control logic, etc.) and the assembly of individual components into a complete system. Therefore, accurate system-level integrated models are becoming a requirement to solve modern NVH problems. Combining the optimal balance between simulation and experimental data, this article describes a joint effort between Ford and Gamma Technologies to develop a general methodology to perform full-vehicle low frequency…

Open-access experimental data for NVH benchmarking of e-machines under electromagnetic excitations

EOMYS Engineering-Karine Degrendele, Jean Le Besnerais
L2EP-Emile Devillers, Michel Hecquet
  • Technical Paper
  • 2019-01-1459
To be published on 2019-06-05 by SAE International in United States
This paper presents an experimental setup dedicated to the analysis of acoustic noise and vibrations due to Maxwell magnetic forces in electrical machines, a significant NVH source in hybrid and electric vehicles traction motors. Both electromagnetic excitations and structural response of the electrical machine are simplified to provide the first public benchmark of e-NVH phenomenon (electromagnetic Noise, Vibration, Harshness). The paper first describes how the testbench is designed and tested to reduce as much as possible modelling and experimental uncertainties. A Permanent Magnet Synchronous Machine topology from EV/HEV application is used to illustrate tooth modulation effect and interaction between radial and tangential force-induced vibrations, and designed to generate the resonance of several stator structural modes with simplified electromagnetic loading (open-circuit case). A larger air gap allows the insertion of a fine search-coil network to measure time and space distribution of the air-gap flux density and resulting Maxwell stress harmonics. Accelerometers are placed on stator tooth tips to capture tooth bending motion, as well as on the outer yoke of the stator. Besides vibration measurements, sound…

Machine Learning Based Technology for Reducing Engine Starting Vibration of Hybrid Vehicles

Toyota Motor Corp.-Kento Shimode, keisuke ishizaki, Masashi Komada
  • Technical Paper
  • 2019-01-1450
To be published on 2019-06-05 by SAE International in United States
Engine starting vibration of hybrid vehicle with Toyota hybrid system has variations even in the same vehicle, and a large vibration that occurs rarely may cause stress to the passengers. The phenomenon analysis based on the vibration theory and statistical analysis has been done to clarify, but the primary factor of the rare large vibration has not been clarified because the number of factors is enormous. From this background, we apply machine learning that can reproduce multivariate and complicated relationships to analysis of variation factors of engine starting vibration. Variations in magnitude of the compelling force such as motor torque for starting the engine and in-cylinder pressure of the engine and timing of these forces are considered as factors of the variations. In addition, there are also nonlinear factors such as backlash of gears as a factor of variation. For the variation factor analysis, it is difficult to measure the physical quantities mentioned above from experiments, because of the high time load of installing measuring sensors and lack of measurement technology for some factors. On…

Highly decorative, lightweight flexible solar cells for automotive applications

Ritsumeikan University-Mikiya Inoue, Jakapan Chantana, Takashi Minemoto
Toyota Motor Corporation-Taizo Masuda, Yuki Kudo
  • Technical Paper
  • 2019-01-0863
To be published on 2019-04-02 by SAE International in United States
In 2012, the U.S. Environmental Protection Agency and National Highway Traffic Safety Administration laid down strict standards for CO2 emissions and improved fuel economy for light-duty vehicles covering the model years 2017 to 2025. In order to meet the requirement, it is essential to develop an alternative power source for the future cars. Power generation by solar cells/modules is a promising renewable energy candidate because the most environmentally friendly vehicles such as electric vehicles and plug-in hybrid vehicles are equipped with large-capacity batteries that can be charged with electricity generated by solar cells/modules. In this study, we developed a simple lift-off process for producing colorful, light-weight, and flexible Cu(In,Ga)Se2 (CIGS) solar cells for automotive application. The developed lift-off process consists of three steps: first, attaching a plastic film on CIGS/glass solar cell at temperature of around 100 °C; second, scribing the cell to the desired area/shape after cooling down; and finally, a back contact is deposited on detached layers. Our measurements show that the fabricated lift-off cells have nearly identical performance compared to that of…

Design of electric motor using coupled electromagnetic and structural analysis and optimization

Altair Engineering-Numair Mazgaonkar, Linus Francis Fernandes
Automotive Accessories-Mazharul Chowdhury
  • Technical Paper
  • 2019-01-0937
To be published on 2019-04-02 by SAE International in United States
Vehicle architecture in existing vehicles is changing continuously due to the need for increasing vehicle electrification. Electric motors have helped sustain this requirement. Traditional internal combustion engines are being replaced or coupled with traction motors or in-wheel motor systems in the full or hybrid electric vehicles. With the use of electric motor in a vehicle, several parts can be reduced. This leads to reduced packaging size and complexity. Also, CO2 emissions are reduced, and overall efficiency is increased. But the task of designing an electric motor which is which assembled in a vehicle could be quite complex. The design of an electric motor can affect the durability, and noise and vibration characteristic of the vehicle structure to which it is connected. The design of the vehicle structure to which the motor attaches should be able sustain the magnetic torque generated by the motor. Electromagnetic forces generated on the stator of an electric motor affect the vibration characteristic of the motor casings and structure to which it connects. In an internal combustion powered vehicle, engines contribute…

How to Model Real-World Driving Behavior? Probability-Based Driver Model for Energy Analyses

Daimler AG-Tobias Schuermann, Tobias Goedecke, Stefan Schmiedler, Daniel Goerke
University of Applied Sciences Esslingen-Kai André Boehm
  • Technical Paper
  • 2019-01-0511
To be published on 2019-04-02 by SAE International in United States
A wide variety of applications such as driver assistant and energy management systems are researched and developed in virtual test environments. The safe testing of the applications in early stages is based on parameterizable and reproducible simulations of different driving scenarios. One possibility is modeling the microscopic driving behavior to simulate the longitudinal vehicle dynamics of individual vehicles. The currently used driver models are characterized by a conflict regarding comprehensibility, accuracy and calibration effort. Due to the importance for further analyses this conflict of interests is addressed by the presentation of a new microscopic driver model in this paper. The proposed driver model stores measured driving behaviors with its statistical distributions in maps. Thereby, the driving task is divided into free flow, braking in front of stops and following vehicles ahead. This makes it possible to display the driving behavior in its entirety. The comprehensibility of this driver model is given by its simplicity and the calibration effort is low with existing measurement data. These data are recorded with a testing vehicle by a map-…
Datasets icon
Annotation icon

Real-World Emission Modeling and Validations using PEMS and GPS Vehicle Data

US Environmental Protection Agency-SoDuk Lee, Carl Fulper, Joseph McDonald, Michael Olechiw
  • Technical Paper
  • 2019-01-0757
To be published on 2019-04-02 by SAE International in United States
Portable Emission Measurement Systems (PEMS) are used by the US Environmental Protection Agency (EPA) to measure emissions from vehicles in normal, in-use, on-the-road operation to support many of its program, including emissions compliance assessment from on-road vehicles, emissions factor assessment for in-use fleet modeling, and collection of in-use vehicle operation data to support vehicle simulation modeling programs. This paper discusses EPA’s use of GPS measured altitude and vehicle speedometer data to provide real-world road grade data for a GT-DRIVE+ vehicle model. The GPS measured altitudes and vehicle speeds were filtered and smoothed by an open-source, Python-based Savitzky Golay filter to estimate the road grades. Ambient temperature, ambient pressure, humidity, wind direction and speeds were used to simulate actual driving environment conditions. Complete engine maps, transmission efficiencies and vehicle data were used as inputs into the GT-DRIVE+ vehicle model to estimate fuel economy, greenhouse (GHG) CO2 and NOx emissions of a hybrid electric vehicle and a vehicle equipped with a 12-volt start/stop system. The model-simulated fuel economy, GHG and NOx emissions, engine torque/speed, and vehicle speeds…

Features of modeling of processes of thermal preparation of the transport engine on the basis of thermal accumulators of a phase transition

Belarusian National Technical University-Heorgi Kukharonak
Donbas National Academy of Civil Engineering & Architecture-Valery Aleksandrov
  • Technical Paper
  • 2019-01-0906
To be published on 2019-04-02 by SAE International in United States
The utilization of different types of energy in phase-transitional thermal accumulators and its further use for thermal development of different subsystems of hybrid vehicles enables to significantly increase their operational efficiency. The system of the combined utilization of thermal and electrical energy in phase-transitional thermal accumulators (TA) is offered. To charge TA, it uses thermal energy of exhaust gas, a coolant and motor oil of the internal combustion engine and electrical energy which is utilized by energy recovery system when braking the vehicle. It consists of consecutive stages of heat accumulation when charging TA from different energy sources of the hybrid vehicle, its storage and use for rapid heating of vehicle separate subsystems. The main heat and power characteristics of system components and heat accumulating materials used in phase-transitional TA have been justified. Schemes and designs of a physical model to utilize electrical energy using high-capacity condensers for charging phase-transitional TA have been offered. The results of experimental and computational studies show theoretical comparison of the main indicators of the developed system in charging phase…