Browse Topic: Hybrid electric vehicles

Items (3,167)

Methodology for Developing a Learning-Based Energy Management Strategy for Hybrid Electric Vehicles via Soft Actor-Critic (SAC) Deep Reinforcement Learning Algorithm

2026-01-0774To be published on 07/01/2026

The optimization of energy management strategies for hybrid electric vehicles is crucial for minimizing fuel and electrical energy consumption while maintaining the energetic stability of the electrical system. Conventional heuristic, rule-based approaches typically rely on classical optimization techniques and manual calibration by experienced engineers. These methods often suffer from simplified assumptions, sub-optimality, and are increasingly time-consuming given the growing complexity of modern hybrid powertrain architectures. This research proposes a novel methodology for the development of a learning energy management strategy based on deep reinforcement learning (DRL) to transition toward highly automated, data-based, and optimization-based development approaches. The methodology utilizes the Soft Actor-Critic (SAC) algorithm, an off-policy actor-critic method, to train an agent through experiences by interacting with an environment. The environment consists of a backward

Metzler, Sebastian, Winke, Florian, Jungen, Mario, Schmiedler, Stefan, Hofmann, Peter, Geringer, Bernhard

Synergistic Integration of Advanced Combustion and Air-Path Technologies to Maximize ICE Efficiency in Hybrid Applications

2026-01-0733To be published on 07/01/2026

This work investigates the efficiency potential of reciprocating internal combustion engines (ICE) for light-duty vehicle propulsion within the current state of the art and a five-year technological horizon. A validated one-dimensional engine model was extended to integrate multiple advanced technologies, including active prechambers for ultra-lean gasoline combustion, thermal coating, an electric turbocharger capable of supplementary turbine work recovery, variable compression ratio, and variable valve timing implementing a Miller cycle. These enhancements are systematically evaluated to explore their individual and combined effects on engine performance and efficiency. Parametric studies quantify the influence of heat transfer, air–fuel ratio, compression ratio, and other key variables on engine output, enabling the generation of enhanced engine performance maps. These maps reflect synergistic interactions between parameter sets and serve as predictive tools for assessing optimized

Pla, Benjamin, Dolz, Vicente, Serrano, Jose R., Gómez-Vilanova, Alejandro, Oliva, Fermin, Cardenas, Maria, Ariztegui, Javier

Multi-Scale Modelling of Localized Battery Degradation in Heavy-Duty Series Hybrids: From Electrochemical Impedance Spectroscopy to Powertrain and Battery Pack Performance

2026-01-0747To be published on 07/01/2026

The operational efficiency of heavy-duty hybrid electric vehicles (HEVs) is intrinsically linked to the health and power capability of the battery pack. Traditional battery management systems often rely on bulk State-of-Health (SOH) metrics, failing to account for localized degradation and the resulting current imbalances within parallel-connected modules. Recent literature emphasizes that cell-to-cell variations and thermal gradients can lead to a 6% reduction in accessible energy and a 5.2% acceleration in degradation rates due to heterogeneous current distribution. This study addresses these gaps by presenting a multi-scale modelling framework that translates cell-level electrochemical degradation features into system-level powertrain optimization. Initially, a thorough experimental campaign was conducted on LFP cells, using accelerated cyclic and thermal aging at 25°C and 60°C. High-fidelity battery parameters were extracted from EIS data using fractional-order equivalent circuit

Safavi, Seyed Reza, Homayouni, Hooman, Shoa, Tina, Wang, Jason, McTaggart-Cowan, Gordon

NVH Design and Refinement of Dedicated Hybrid Engine on Range-Extended Electric Vehicle

2026-01-0688

To be published on 06/20/2026

Simplicity and electrification of the propulsion system are one of the most important trends in vehicle development and integration process. The complexity of NVH (Noise, Vibration and Harshness) design and refinement is the core challenge to this process. Customers’ expectations of an unnoticeable engine during driving make this challenge more critical [1]. Apart from the overall sound pressure level, the sound quality is even more important due to the lack of noise masking effects [2]. Therefore, the development team has reached an internal consensus that NVH attributes are the top priority in engine development. This paper describes the NVH development process of a dedicated hybrid engine for the range extender electric vehicle (REEV) application, beginning with an introduction to REEV system as well as the operating condition data of long-distance road tests. Based on the road test data, the engine technical specification is defined accordingly and broken down into design targets

Wang, Hao, Zhang, Guiqiang

Potential of ORC-Based Waste Heat Recovery in Conventional and Hybrid Heavy-Duty Powertrains

2026-37-0018

6/9/2026

Heavy-duty vehicles significantly contribute to greenhouse gas emissions and urban air pollution, especially during cold-starts and transients when engine and aftertreatment efficiencies drop. Waste heat recovery (WHR) via Organic Rankine Cycle (ORC) systems offers a practical solution to improve fuel efficiency and cut CO₂ in real-world heavy-duty operations. This study examines ORC-based WHR integration into conventional and hybrid powertrains of an Isuzu FTR850 truck, analyzing four configurations: Shell-and-Tube or Plate heat exchangers with simple or regenerative ORC layouts. For hybrids, it compares two engine sizes and energy management strategies: an optimized fuzzy logic approach versus constant-power operation to enhance exhaust heat recovery. A validated quasi-static simulation framework is used to predict fuel consumption and exhaust properties over representative duty cycles. 2D performance maps using exhaust temperature and mass flow as inputs are used to model the WHR

Donateo, Teresa, Morrone, Pietropaolo

Heavy-Duty Nonroad Material Handler Electrification Part 2: Energy Efficiency and Performance Evaluation

02-19-03-0016

6/2/2026

Decarbonization efforts achieved through electrification in nonroad mobile machinery can realize a reduction in fuel consumption of more than 20%, thanks to concepts familiar to light-duty passenger vehicles. This case study compares the results of a hybrid-electric material handler to its conventional counterpart, utilizing machine-specific drive cycles presented in part one of this paper series. The hybrid prototype features an extended-range electric vehicle (EREV) powertrain that demonstrated substantial energy efficiency improvements. Specifically, there was a reduction in equivalent fuel consumption of 75% when operating in electric-only mode, and 33% when maintaining the battery by charging with an on-board generator. Together, the efficiency improvements can be extrapolated over a low-intensity, 8-h shift characterized by significant idle time and highly dynamic engine load for a 47% reduction in net energy consumption. Key technologies that led to this improvement included

Czarnecki, Alexander, Goodenough, Bryant, Worm, Jeremy, Robinette, Darrell, LaTendresse, Phil, Westman, John, Subert, David, Heath, Matthew, Kiefer, Dylan, Black, Andrew

A Study on the Future of Battery Based Electric Aircraft Propulsion

2026-26-0782

6/1/2026

Today the aviation industry is witnessing a paradigm shift in the propulsion technology which has been unseen since the 1930s, when the gas turbine took over from the more established piston engines. For the emerging electric propulsion to survive and flourish, it must demonstrate clear superiority over the mature baseline technology of the gas turbine. It is a fact that the current battery technology is a limiting factor as it is not competitive compared to a gas turbine that is 30-50 times more energy dense. Naturally, the present electric propulsion developments concentrate on smaller aircraft applications and use on a large aircraft is possibly decades away. Apart from the energy density, from a thermal perspective the architectures are vastly different from each other. A conventional aircraft fitted with a gas turbine has readily available heat sinks in fuel and air that aids in heat transfer. Compressed air bleeds from the engine manage the thermal demands of the engine itself

Arun, K P, Srinivas, Varsha, Joshi, Jayanth, Suresh, Chandini, Naskar, Proloy Jyoti

Design and Performance Research of an Integrated Thermal Management System for Hybrid Electric Light Trucks

2026-99-0735

5/15/2026

Addressing issues in traditional hybrid light trucks—such as low overall energy utilization efficiency and performance degradation of key components under extreme operating conditions—this study presents a novel, high-efficiency, integrated vehicle thermal management system. By coupling various subsystems, the system achieves efficient and rational utilization of the vehicle’s overall energy consumption. Comparative simulation analyses were conducted under different ambient temperatures and initial state-of-charge (SOC) levels to verify the reliability of the designed integrated thermal management system. Results show the system can meet the temperature requirements of all components under both high and low-temperature conditions. Meanwhile, findings indicate that ambient temperature and power modes have a substantial impact on the temperature of each component, and there is potential for utilizing motor waste heat. These outcomes provide a reference for the subsequent optimization of

Meng, Shun, Zhang, Chunyu, Zhang, Yu, Zhang, Dong, Yao, Mingyao, Qiu, Liang, Wu, Yadong, Qian, Yejian

Research on Waste Heat Recovery Characteristics of Electric Drive System in Hybrid Electric Light-Duty Trucks

2026-99-0722

5/15/2026

Aimed at the high energy consumption for battery heating of a light hybrid truck in low-temperature winter, this paper proposes an optimized battery thermal management scheme based on motor waste heat and PTC cooperation. Then it verifies its energy-saving performance based on multi-condition simulation and testing. Taking the constant-speed condition at -5°C as an example, firstly, the accuracy of the battery thermal management model is verified by comparative simulation and test. Then, based on the verified model, the battery thermal management model is simulated under typical winter conditions at 0°C and 5°C. The analysis results show that, when the battery temperature is raised from the initial state to a certain target, the energy consumption of the motor waste heat-assisted PTC heating scheme is obviously less than that of PTC heating. The energy saving rates are 33.137% at -5°C, 32.45% at 0°C, and 32.56% at 5°C, respectively. The research results have proved that the effective

Meng, Shun, Zhang, Dong, Zhang, Yu, Zhang, Chunyu, Yao, Mingyao, Qiu, Liang, Qian, Yejian

Engine Park Angle Control via Electric Machine under Varying Deceleration Limits

2026-01-0445

4/7/2026

Accurate control of the engine park angle during Autostop in hybrid vehicles is critical for enabling rapid and smooth Autostarts, reducing start-up vibrations, and enhancing overall driving comfort. However, in real-world scenarios, the available torque for engine positioning is often limited by competing driver torque demands, battery discharge constraints, and the state of charge (SoC). Under these conditions, conventional position-speed control strategies frequently fail to achieve the desired precision. This paper introduces an adaptive control strategy for the electric machine (EM) that drives the internal combustion engine, ensuring precise alignment of the crankshaft at a predefined angle to optimize restart conditions. Upon receiving an engine shutdown request, the proposed controller computes an adaptive deceleration profile that respects the EM’s torque and deceleration limits while guiding the crankshaft toward the target park position. The core of the approach lies in

Purohit, Punit, Achir, Ali, Bhakare, Allwyn

Development of a Model-Aware Data-Driven Control Algorithm for a Drive-by-Wire System for a Level 4 Automated Vehicle

2026-01-0043

4/7/2026

Precision control in Level 4 Automated Vehicles is essential for enhancing operational efficiency, accuracy, and safety. This work, conducted as part of ARPA-E’s NEXTCAR program, focuses on developing a robust hardware and software control solution to enable drive-by-wire functionality. A previous publication by the authors presented the hardware solutions for overtaking stock vehicle controls. This paper focuses on a model-based and data-driven control algorithm to enable drive-by-wire functionality for longitudinal and lateral motion control for a 2021 Honda Clarity Plug-In Hybrid Electric Vehicle. This vehicle was equipped with a set of sensors and an onboard processing unit to enable Level 4 automation. For lateral controls, an algorithm was developed to command steering torque to the electronic power steering module, ensuring the vehicle could attain the desired steering angle position at varying speeds. The system leveraged feedforward and feedback mechanisms. Feedback controller

Adsule, Kartik, Bhagdikar, Piyush, Drallmeier, Joseph, Alden, Joshua, Gankov, Stanislav

A Novel Power-Split Hybrid Electric Architecture for Off-Road Tracked Vehicles: Design and Performance Evaluation

2026-01-0258

4/7/2026

Tracked off-road vehicles operate at low speeds with high tractive effort and frequent skid-steer maneuvers, conditions that push torque and power demand to extremes and exacerbate powertrain efficiency losses. Electrification can improve energy conversion and mobility for such duty cycles. This paper introduces a novel power-split hybrid electric architecture for a tracked vehicle and benchmarks it against three designs: a conventional mechanical driveline, a series hybrid, and a P2 parallel hybrid. To enable fair, architecture-agnostic comparisons, a supervisory controller based on Stochastic Dynamic Programming (SDP) schedules engine operation and power flow across all layouts under representative off-road scenarios, including skid-steer events, with varying terrain and power-demand profiles. Results show higher energy conversion efficiency (lower fuel use) for the proposed power-split architecture, followed by the parallel, then series, and lastly conventional configuration across

Ghate, Atharva, Sundar, Anirudh, Zhu, Qilun, Prucka, Robert, Figueroa-Santos, Miriam, Barron, Morgan, Castanier, Matthew P.

Identifying Patterns of Real-World Charging Frequency for a Sample of Plug-In Hybrid Electric Vehicles in North America

2026-01-0429

4/7/2026

Plug-in Hybrid Electric vehicles (PHEVs) have the capability to effectively utilize electricity from the grid as an energy source for powering an appreciable portion of the total vehicle miles travelled (VMT), thereby reducing greenhouse gas (GHG) emissions, since the Carbon Intensity (CI) of electricity is often less than that of liquid fuels in many parts of the world. Several real-world usage factors can affect the fraction of VMT electrified, with the frequency of charging being one of the most influential factors. Studies in recent years have attempted to characterize the real-world performance of PHEVs based on long-term average fuel consumption and/or other data flags in the readout from vehicle On-Board Diagnostics (OBD), but such approaches are unable to infer accurate estimates for the occurrence of charging events. This paper adopts an approach that relies on analysis of highly granular (trip by trip) information obtained from vehicles equipped with a data communication

Hamza, Karim, Laberteaux, Kenneth

A Study on Fail-Safe and Limp-Home Strategies for Electric Drive Failures in P1-P2 (P)HEVs

2026-01-0427

4/7/2026

Hyundai Motor Company’s TMED-II hybrid system adopts a P1–P2 parallel motor layout, which improves power distribution flexibility but increases reliance on electric drive components. Failures in motors, inverters, or other power electronics can critically affect drivability and safety, making robust Fail-Safe strategies essential. This study proposes a three-stage, sequential Limp-Home strategy for P1–P2 HEVs under P2 motor system failure. Unlike conventional methods that open the main relay and rely solely on the engine, the proposed approach keeps the high-voltage (HV) system active whenever possible to maintain performance, safety, and comfort. Stage 1 – P1 motor-based State of Charge (SOC) control: Keeps the main relay closed and uses the P1 motor to maintain SOC within set limits. Overcharge is mitigated by operating the motor in discharge mode, and overdischarge is mitigated through regenerative operation. Engine torque is adjusted to match motor torque demand, preserving launch

Rho, Jeongwon, Park, Sangcheol, Oh, Sung Hwan

Electrified Propulsion System Balancing for Light Duty Full Size Truck and Sport Utility Vehicles: A 2026 North American Market Perspective

2026-01-0412

4/7/2026

Achieving the stringent EPA CAFE 2032 standards for light-duty full-size trucks and sport-utility vehicles (SUVs) in North American poses significant challenges. While Battery Electric Vehicles (BEVs) offer a clear path to zero tailpipe emissions, their widespread adoption in this segment faces hurdles including range anxiety, payload/towing capabilities, and traditional truck/SUV use cases. This paper investigates a balanced approach, focusing on optimizing propulsion system design with appropriate hardware content, can effectively meet future fuel economy and emissions standards. This investigation examines advanced BEVs and hybrid electric vehicle architectures, including full hybrids (HEVs), and plug-in hybrids (PHEVs) tailored for full-size trucks and SUVs. Considerations include the optimal sizing of internal combustion engines, electric motors, and battery packs to deliver robust performance while maximizing energy efficiency. This paper analyzes the integration of technologies

Babcock, Dillon, Robinette, Darrell

A Latent Space Framework for Modeling Transient Engine Emissions Using Joint Embedding Predictive Architectures

2026-01-0423

4/7/2026

Accurately modeling and controlling vehicle exhaust emissions, particularly during highly transient events such as rapid acceleration, is crucial for meeting stringent environmental regulations and optimizing modern powertrain systems. While conventional data-driven modeling methods, such as Multilayer Perceptrons (MLPs) and Long Short-Term Memory (LSTM) networks, have improved upon earlier phenomenological or physics-based models, they often struggle to capture the complex nonlinear dynamics of emission formation. These monolithic architectures attempt to learn from all available data, which increases their sensitivity to dataset variability. They often require increasingly deep and complex architectures to improve performance, thereby limiting their practical utility. This paper introduces a novel approach that overcomes these limitations by modeling emission dynamics in a structured latent space. Using a rich dataset combining real-world driving data from a Portable Emission

Sundaram, Ganesh, Gehra, Tobias, Ulmen, Jonas, Heubaum, Mirjan, Görges, Daniel, Günthner, Michael

The Impact of Mid-Level Ethanol Blends on Reliability, Performance and Emissions in Gasoline Engine

2026-01-0302

4/7/2026

To reduce CO₂ emissions from automobiles, it is essential to improve system efficiency through the electrification of vehicles with internal combustion engines (ICEs), such as hybrid electric vehicles (HEVs) and plug-in hybrid electric vehicles (PHEVs), as well as through enhancements in ICE thermal efficiency. Additionally, biofuels and synthetic fuels are gaining attention as promising options to reduce CO₂ emissions from existing vehicles. Among these alternative fuels, ethanol, a bio-derived fuel, is already used at varying concentrations in many countries, and its further adoption is expected. Expanding the fleet of flex-fuel vehicles (FFVs) capable of running on high ethanol blends is one approach; however, increasing ethanol content in conventional gasoline, which is more widely used, is considered to have a greater impact on CO₂ reduction. A key issue is how existing vehicles adapt to increased ethanol concentrations such as E20, E30, and E40. This study focuses on turbocharged

Matsubara, Naoyoshi, Sugata, Kenji, Koyama, Takashi, Ochi, Yuta, Aoki, Mizuki, Hashima, Takashi, Kodama, Kohei, Tomoda, Keiju, Kojima, Masakiyo

The Effects of Ethanol on Combustion in a Super-Lean-Burn Engine

2026-01-0303

4/7/2026

To mitigate global warming, many countries are working toward carbon neutrality. Reducing CO₂ emissions from vehicles requires electrification technologies in hybrid and plug-in hybrid electric vehicles (HEVs, PHEVs) and improving thermal efficiency of internal combustion engines (ICEs). Lean-burn combustion is one approach to improving ICE thermal efficiency. Biofuels and synthetic fuels can also reduce CO₂ emissions in existing vehicles. Ethanol, a bio-derived fuel, is widely used in varying contents worldwide, and its further utilization is anticipated. This study examines the effects of ethanol blending on emissions, thermal efficiency, knocking, and combustion speed in a super-lean-burn engine. Gasoline surrogates with varying ethanol contents were tested at an excess air ratio (λ) of 2.5. Higher ethanol content reduced nitrogen oxides (NOx) emissions due to lower adiabatic flame temperature. Total hydrocarbon (THC) emissions measured by a Flame Ionization Detector (FID) showed a

Sugata, Kenji, Matsubara, Naoyoshi, Yamada, Ryota, Kitano, Koji

Methods of Highly Repeatable Lubricant Testing for Electrified Vehicles: Universal Motor Control and Statistical Test-Variation Analysis

2026-01-0421

4/7/2026

This paper describes a systematic approach to evaluate lubricants for hybrid and electric vehicles (xEVs) that can detect impacts on efficiency as low as 0.1 percentage points. Two testing methods were developed to evaluate lubricants’ efficiency effects: (1) on a complete vehicle (using the manufacturer’s hardware and motor control) and (2) on a standalone drive unit (using custom power electronics and control). A Monte Carlo simulation was used to analyze the resulting data to determine the detection limits of the vehicle test method. To evaluate the effectiveness of the test stands and the data-analysis method, a Tesla Model 3 electric drive unit and a Chevrolet Bolt battery electric vehicle (BEV) were characterized for system efficiency. For the Bolt mounted on a hub driven chassis dynamometer, this method is capable of detecting a change in the drive unit’s electromechanical efficiency between baseline and candidate fluids of <0.4 percentage point (pp) with 95% confidence at most

Luo, Yilun, Gross, Michael, Kostan, Travis

Propulsion System Design Considerations for HEV Versus EV Applications

2026-01-0641

4/7/2026

The design and development of EVs and HEVs has become a growing issue recently due to concerns about pollution and dependence on non-renewable fossil fuels. Accordingly, General Motors (GM) has an evolving vehicle electrification plan over the past several decades and into the future to deliver low-cost and efficient EVs and HEVs. Propulsion system requirements for the applications of EV and HEVs are quite different and therefore, the design principles and directions are also distinct between these cases. From micro-hybrid and full plug-in hybrid applications to full EV applications, design requirements, strategies and outcomes can widely vary. Continuous and peak duty are substantially different depending on the application of the vehicle. Motor operational duty is significantly higher for EV compared to the electric motor of a hybrid electric vehicle. Motor torque, power and efficiency requirements are also higher for EV motors, which greatly influences the choice of motor type and

Momen, Faizul, Jensen, William, Das, Shuvajit, Chowdhury, Mazharul, Alam, Khorshed, Anwar, Mohammad, Reinhart, Timothy

In-Use Life Digital Twin (Redundant Storage) and Swappable Use Case for Battery Durability

2026-01-0397

4/7/2026

As regulatory frameworks for zero-emission vehicles (ZEVs) and battery electric vehicles (BEVs) continue to evolve, there is growing emphasis on monitoring battery durability and usage throughout the vehicle lifecycle. These regulations increasingly specify the use of data monitors and tracking mechanisms to assess battery health and performance. In addition, regulations require anti tampering mechanisms especially for monitors that have external write access. Historically, regulations focused primarily on vehicle warranty; however, with the introduction of battery durability monitors, clarity is needed for the new battery durability monitors. More specifically if the battery durability monitors track with the lifetime of the vehicle or if they follow the lifetime of the battery. Furthermore, current regulations provide no guidance on high-voltage (HV) traction battery service strategies or methods to protect monitors from tampering by external customers. This paper will classify

Laskowsky, Patricia, Bunnell, Justin, Zettel, Andrew, Albarran, Josue

Comparison of Ammonia Emission Characteristics Between Different Gasoline Vehicles Equipped with Three-Way Catalysts

2026-01-0374

4/7/2026

In recent years, the tightening of vehicle emission regulations has led to a decreasing trend in regulated pollutants such as NOₓ and CO. However, the emission of ammonia (NH₃), which is unintentionally generated during the purification process in three-way catalyst of gasoline vehicles, has become a growing concern. NH₃ emissions from vehicles can serve as a precursor to PM2.5 and have been reported to cause local roadside pollution. Therefore, there is a growing need for on-road testing to identify conditions under which NH₃ is likely to be emitted. Furthermore, since engine control strategies vary among vehicle types, it is desirable to consider differences in emission behavior across different models. In this study, on-road NH₃ emissions were measured for multiple vehicle models with different powertrains, and the effects of engine behaviors and engine operating duration across vehicles on NH₃ emissions were investigated. To analyze differences in NH₃ emission behavior among

Ashizawa, Keigo, Fukunaga, Chisato, Gao, Tianyi, Sato, Susumu

Establishing a Standard S-Factor: Improving Accuracy and Flexibility in SOC Corrections for HEV Testing

2026-01-0422

4/7/2026

Hybrid-electric vehicle (HEV) fuel economy test procedures require that the net energy change (NEC) of the battery not interfere with measuring accurate fuel consumption results. SAE J1711-2010 required the NEC to stay within 1% of fuel energy consumption, assuming that residual changes in state of charge (SOC) would have negligible impact. In practice, however, the asymmetry between fuel and electricity conversion efficiencies means that an imbalance of one unit of battery energy can translate into a likely fuel consumption error of roughly three units. A standard S-Factor, a dimensionless ratio of marginal fuel change to marginal NEC change, was introduced in J1711-2023 to improve SOC correction procedures. The method improves upon the previous J1711 (2010) accuracy by correcting all results for NEC changes and expands the NEC-to-fuel ratio (NECFR) window, enabling HEVs to use electric propulsion more aggressively and potentially achieve higher fuel economy in testing and real-world

Duoba, Michael

Multi-Body Dynamics Control Integration Tool Application in Hybrid Vehicle System Identification

2026-01-0417

4/7/2026

The multi-body dynamics (MBD) model and the MATLAB Simulink model can be integrated to create a control-integration model. Using a high-fidelity MBD model to represent the vehicle as the plant, this integrated model can be used to analyze vehicle system physics and develop control strategies. For hybrid vehicles, this process is more complex because the powertrain and other vehicle systems are often built as separate MBD models. This paper describes a method for integrating a powertrain model developed in AMESIM, a vehicle model developed in SIMPACK, and a control model developed in MATLAB Simulink. The resulting integrated model was then used to perform frequency sweep analysis to identify driveline system properties. In particular, the driveline frequency and the amplitude of the transfer function between motor speed and motor torque are critical parameters. By applying active damping control to the driveline system, the peak amplitude and driveline vibrations can be reduced. The

Xing, Xing, Mathew, Vino

Real-Time Observations of the Effect of Fuel Dilution in an Engine Transient Friction Rig. Along with Real-Time Observations of Fuel Entering and Leaving Internal Combustion Engine Oil, over Both Standard Engine, ICE and Plug-In Hybrid, PHEV Dynamic Drive Cycles

2026-01-0351

4/7/2026

Hybrid electric vehicles (HEVs) with an increasing level of electrification, are becoming a major part of the global energy transition. To achieve lower engine tailpipe exhaust emissions and improve total fuel consumption, typically the HEV control system expertly and frequently switches between the internal combustion engine and electric motor drive, with multiple stops and restarts of the internal combustion engine (ICE). As a consequential result of this switching, are typically slower or even incomplete engine warm-up times, depending on the engine speed, load pattern and run time of the vehicle drive cycle. Along with the speed and load transient control, the engine stop and start processes are also challenging to control, with respect to cold start fuel and combustion by-products entering the oil. Consequently, contamination enters the engine oil but may not completely leave. These effects are highly transient over the drive cycle. Contaminants and in particular, fuel dilution

Butcher, Richard, Bradley, Nathan, Thedering, Dennis

Development of Honda S+ Shift Utilizing e:HEV System

2026-01-0418

4/7/2026

Honda is promoting mobility electrification to realize a carbon-neutral society by 2050. Hybrid vehicles will remain advantageous over electric vehicles in terms of manufacturing cost and driving range until renewable energy usage increases, charging infrastructure is sufficiently developed, and battery costs are reduced. In response to this situation, Honda has developed a new control system, “Honda S+ Shift”, which further enhances the “emotional value of driving pleasure” inherent to the e:HEV system and creates new value for hybrid vehicles. Honda S+ Shift synchronizes the engine and vehicle speed and selects a virtual gear position according to the driver's operation such as acceleration, cornering, and deceleration. Subsequently, the system achieves the required system output in cooperation with a dedicated energy management system. It also works with each vehicle system, such as drive force control, sound control, and meter cluster, to stimulate all five senses of the driver

Murata, Naoya, Narimoto, Ryosuke, Saito, Masatoshi, Ishida, Daichi, Gunji, Hiroki, Mitogawa, Terumasa, Ukai, Yohei, Kurachi, Shinobu, Nagakura, Akari, Shiki, Kazuki, Maeda, Sadaharu

Meeting the Challenges of PHEVs/REEVs Lubrication: Insights from Comprehensive On-Road Fleet Tests

2026-01-0354

4/7/2026

Driven by increasingly stringent emissions regulations, rapid advancements in electrification technologies, and rising consumer demand for fuel-efficient and environmentally sustainable mobility, Plug-in Hybrid Electric Vehicles (PHEVs) and Range-Extended Electric Vehicles (REEVs) have seen substantial growth in the global automotive market. These hybrid architectures integrate electric propulsion with Internal Combustion Engines (ICEs), offering extended driving range and operational flexibility. However, the evolution of hybrid powertrain systems introduces distinct operating characteristics—such as frequent engine start-stop events, reduced average engine loads, and extended oil drain intervals—that diverge significantly from conventional ICE vehicle usage profiles. These changes present new challenges for engine lubricants, which must maintain performance under intermittent engine operation, increased exposure to water and fuel, and fluctuating thermal and environmental conditions

Zhang, Ruifeng, Andrew, Rhiann, Hu, Gang, Lim, Pei Yi, Lu, Hongjie, Moizan, Simon

Development of a Zeolite-Based (HC/NOx Trap Type) Cold-Start Catalyst (CSC) for Meeting Tier4/LEV IV Tailpipe Emission Standards, Part IV

2026-01-0364

4/7/2026

This paper is a follow-up study to three preceding reports [1,2,3] that focus on the development of a β-zeolite-based hydrocarbon/nitrogen oxide (HC/NOₓ) trap-type cold-start catalyst (CSC) — a cost-efficient technical strategy for meeting the increasingly stringent vehicle tailpipe emission standards for automotive exhaust systems, including Tier 4 and LEV IV, which are to be enforced in the near future. A core challenge in meeting Tier 4 and LEV IV exhaust emission standards lies in the fact that both the SC03 and US06 test cycles commence from ambient (cold) temperatures, as opposed to the elevated (hot) starting temperatures mandated for the preceding Tier 3 and LEV III standards. In the present study, a hybrid electric vehicle (HEV) fitted with two distinct Tier 3-certified exhaust aftertreatment systems—one officially certified to Bin 30 standards and the other a Bin 20-equivalent system (non-officially certified)—was subjected to testing under the cold SC03, cold US06, hot SC03

Xu, Lifeng, Wei, Hong, Zhao, Pengfei, Ma, Ruibo, Wang, Lin, Qian, Wangmu, Qian, Menghan

BEV Incremental CO ₂ Emissions in a Ranked Order Electric Grid

2026-01-0424

4/7/2026

Battery Electric Vehicles (BEV) have been sold as ‘Zero Emissions Vehicles’ (ZEV) by governments to reduce transportation CO2. While they are not ZEV because they run on grid electricity, they could be ‘effectively ZEV’ if the incremental CO2 is ‘very small’. At the national level, this is estimated using following metrics: (1) Internal Combustion Engine Vehicle (ICEV) fuel consumption, from the total US gasoline consumption divided by the total fleet miles driven, 25 mpg or 350 g CO2/mi, (2) Strong Hybrid Electric Vehicles (HEV) about one third less, 240 g CO2/mi. (3) BEV energy consumption, using data from systematic on-road testing of a wide range of vehicles, estimated at 40 kWh/100 mi for a US sales mix. (4) Electricity marginal CO2: in a ranked order grid, zero-CO2 sources are prioritized and supplemented by fossil sources. IEA hourly data show that the US 48 contiguous states are self-contained, with zero-CO2 sources providing a third of total demand. The response to hourly

Phlips, Patrick

Development of BYD Flat Engine for Luxury Hybrid Vehicles

03-19-02-0007

2/24/2026

To meet the requirements of luxury hybrid vehicles regarding engine power, torque, size, and NVH performance, BYD independently developed a 2.0 T flat engine. Designs such as increased intake valve lift, widened intake valve profile, swept piston bowl, and extended exhaust backflow region optimized in-cylinder airflow, enabling the BYD flat engine to achieve a maximum power of 180 kW and a peak torque of 380 N·m. This engine is 820 mm in length, 430 mm in width, and 420 mm in height, saving approximately 45% in volume compared to a competitor engine. The lubrication challenges of the flat engine were addressed through the coordinated implementation of a dry sump system, a multifunctional oil pump, and piston ring orientation design. A novel parameterized modal analysis methodology (considering phase and amplitude) was used for optimizing NVH performance. In synergy with the sandwich-type soundproof plates and four-sided acoustic encapsulation, the noise level (1-m sound pressure level

Pan, Shiyi, Zhang, Nan, Wang, Qiang, Liu, Jun, Liu, Jing, Xu, Zhiqin, Zheng, Junli, Li , Cunshuo

Development of Plug-In Hybrid Motorbike and Analysis towards Sustainable Urban Mobility

2026-28-0111

2/12/2026

The transportation system is one major catalyst to urban ecological imbalance. In developing countries, two-wheelers are considered a major mode of urban personal transportation because of their compactness, easy maneuver in heavy traffic and good fuel efficiency. In India, middle and lower middle-class people prefer to choose two wheelers, and these vehicles are dominantly fuelled by gasoline. Although, the energy consumption by a two-wheeler is comparatively less than that of a four-wheeler, they use about 60% of the nation’s petroleum for on-road vehicles and the impact on urban air quality and climatic change is significantly high. This high proportion of gasoline utilization and emission contribution by two wheelers in cities demand greater attention to improve urban air quality and near-term energy sustainability. Electrification of two-wheelers through the application of a plug-in hybrid idea is a promising solution. A plug-in hybrid motorbike was developed by putting forth a

Kannan, Prashanth, Shaik, Amjad, Talluri, Srinivasa Rao

TOC

99-08-01-0TOC

2/11/2026

TOC

Tobolski, Sue

PRODUCT BRIEFS

26AUTP02_17

2/1/2026

Hybrid Topology Selection & Optimization of a Compact SUV to Meet Future CO ₂ Norms – an Indian Case Study

2026-26-0077

1/16/2026

Rising environmental concerns and stringent emissions norms are pushing automakers to adopt more sustainable technologies. There is no single perfect solution for any market and there are solutions ranging from biofuels, green hydrogen to electric vehicles. For Indian market, especially in the passenger car segment, hybrid vehicles are favoured when it comes to manufacturers as well as with consumer because of multiple reasons such as reliability, performance, fuel efficiency and lower long-term cost of ownership. For automakers planning to upgrade their fleets in the context of upcoming CAFE III (91.7 g CO2 / km) & CAFE IV (70 g CO2/km) norms, hybridization emerges as the next natural step for passenger cars. Lately, various state governments have also promoted hybrid vehicle sales by offering certain targeted tax breaks which were previously reserved for EVs exclusively. Current study focuses on various parallel hybrid topologies for an Indian compact SUV, which is the highest

Warkhede, Pawan, Keizer, Ruben, Sandhu, Rouble, Emran, Ashraf

Development and Validation of a 1D Model for Evaluating Transmission Efficiency in Vehicles

2026-26-0066

1/16/2026

This study develops a one-dimensional (1D) model to enhance transmission efficiency by evaluating power losses within a transmission system. The model simulates power flow and identifies losses at various stages such as gear mesh, bearing, churning, and windage losses. Using ISO/TR 14179, which provides a method for calculating the thermal transmittable power of gear drives with an analytical heat balance model, the 1D model ensures accurate thermal capacity evaluation under standard conditions. A key advantage of this 1D model is its efficiency in saving time compared to more complex 3D modelling, making it particularly useful during the conceptual stage of transmission system development. This allows engineers to quickly assess and optimize transmission efficiency before committing to more detailed and time-consuming 3D simulations. To validate the model, experimental tests were conducted at various motor speeds (RPM) and torque values, using high-precision sensors and dynamometers

Bandi, Nagendra Reddy, Kolla, Kalyan, P, Selvandran, Pulugundla, Krishna Chaitanya, M A, Naveen Kumar

Prediction of REESS Factor for SOC Correction in Hybrid Vehicles

2026-26-0471

1/16/2026

The regulatory mechanisms to measure emissions from automobiles have evolved drastically over the years. Certification of CO2 emissions is one of them. It is not only critical for environmental protection but can also invite heavy fines to OEMs, if not complied with. In homologation test of a Hybrid Vehicle, it is necessary to correct the measured CO2 to account for deviations in measurement from failed Start-Stop phase and difference between start and end State of Charge (SOC) of battery. The correction methodology is also applicable for vehicle simulation in Software-in-Loop environment and for analyzing vehicle test data for CO2 emissions with programmed digital tools. The focus of this paper is on the correction of CO2 derived from SOC delta in the WLTP homologation drive cycle. The battery energy delta due to difference in SOC between start and end of drive cycle should be converted to corresponding CO2 expended from Internal Combustion Engine. The resulting correction factor is

Gopinath, Shravanthi Poorigali, Khatod, Krishna

E-Drive System Selection Criterion for Hybrid Electric Heavy Commercial Vehicles Segments

2026-26-0467

1/16/2026

The automotive industry has been expediting progress toward electrification since climate change driven by global warming represents a significant environmental challenge with far-reaching implications. While electric vehicles offer considerable potential for mitigating CO₂ emissions, their elevated upfront costs pose a notable challenge to large-scale market penetration. Hybrid electric vehicles can serve as an effective intermediary solution, bridging the gap between conventional internal combustion engine vehicles and fully electric vehicles, owing to their comparatively lower initial costs. Hybrid electric vehicle component selection is a complex process that must fulfill multiple requirements: fuel economy, performance, drivability, packaging, total cost of ownership and comfort. Additionally, the selection of hybrid configuration also plays a vital role in determining the cost of the hybrid electric vehicle. Hence, it is a great challenge to select the right powertrain

Shendge, Raman, Jadhav, Vaibhav, Wani, Kalpesh, Warule, Prasad

Simulation Research on Torque Vectoring, Braking, Chassis Control Strategies for Electric & Hybrid Vehicles using System Simulation

2026-26-0423

1/16/2026

Electric Vehicles and Plug-in Hybrids alleviate the energy crisis but pose a unique challenge for vehicle dynamics. Though significant developments in motor control strategy and energy density management are evolving, we face significant challenges in torque management, with several ADAS features being an integral part of the EVs/xHEVs. It demands high-fidelity physical and control model exchanges between electric chassis, ride-handling, tire modelling, steering assist, powertrain, and validation using a 0D–1D platform. This paper explicates a unified strategy for improving overall vehicle performance by intelligently distributing and coordinating drive torque to enhance traction, stability, and drivability across diverse operating conditions through co-simulation. The co-simulation platform includes physical models in AMESIM, and control strategies integrated in MATLAB/Simulink. The platform features comprehensive representations of digital vehicles that require detailed modelling of

Eruva, Patrickxavier, Sarapalli Ramachandran, Raghuveeran, Chougule, Sourabh, Natanamani-Pillai, Siva Subramanian, Scheider, Clement, Leclerc, Cedric, Natarajasundaram, Balasubramanian

Multiphysics Analysis of Heat Sink Designs for Efficient Thermal Performance in Power Electronics Systems

2026-26-0446

1/16/2026

The thermal management capability of power electronic (PE) systems has a critical impact on the performance and efficiency of electric, fuel cell, or hybrid vehicles. Bus bars, high resistance sensor devices, semiconductor switches, power capacitors are the primary components, which make a major contribution in total heat generation in electrical drive unit. As PE packaging sizes are projected to become smaller, the challenge of managing increased heat dissipation becomes more critical. This paper numerically compares six different cooling strategies to determine the best possible thermal management scenario. A coupled physics co-simulation framework is used to analyze a 35W motor inverter integrated with water cooled heat sink. A multi-physics finite element model, integrating fluid, electrical, and thermal fields, is employed to analyze heat generation within the PE system and the associated cooling mechanisms. The power losses from the inverter system are dynamically computed in 1-D

Singh, Praveen Kumar, Natarajan, Nesamani, Murali, Sariki

HIL Simulation of Power Electronics Switching Circuit for Automotive Software Application

2026-26-0516

1/16/2026

Power electronics switching applications are essential for energy management and conversion in automotive electric vehicles (EVs). This paper focuses on DC-DC converters, particularly the integration of 48V DC-DC converters in modern automotive systems. These converters are crucial for efficient power delivery to auxiliary systems such as infotainment, lighting, safety electronics, and thermal management units. In mild hybrid electric vehicles (MHEVs), 48V systems support advanced features like regenerative braking, electric turbocharging, and start-stop functionality. To ensure the reliability, safety, and performance of these converters, Hardware-in-the-Loop (HIL) testing has emerged as a powerful validation technique. HIL enables real-time simulation of the converter’s electrical environment and load conditions, allowing comprehensive testing of the control system without high-level voltage, significantly reducing development time, cost, and risk. The methodology involves utilizing

Yadav, Vikaskumar, Wakure, Vinod

Validation of 0D-1D Co-Simulation Strategies in Cold Conditions for ‘Full EV Digital Vehicle’

2026-26-0448

1/16/2026

Electric Vehicles (EV) are embedded with increased software algorithms coupled with several physical systems. It demands the efficacy of components which are linked together to build a system. The digital models reviewed in this paper are at system-level and full vehicle-level, comprising many components and control design, analysis, and optimization. Systems pertaining to each functionality such as, A/C (Air Conditioning) loop, E-Powertrain (Electric Powertrain), HEVC (Hybrid Electric Vehicle Controller), Cooling system, Battery Management System (BMS), Vehicle control system etc. together make an ‘Integrated Digital Vehicle.’ Fidelity of Intersystem co-simulation [AMESIM + SIMULINK] is key to validating thermal and energy strategies. This paper elucidates the correlation of Digital Vehicle compared to Test for Thermal Strategy in different driving scenarios and Energy management. Validation of Digital vehicle with 52kWh, 40kWh High Voltage Battery for Intercity Travel of Customer

Sarapalli Ramachandran, Raghuveeran, Srinivasan, Rangarajan, Saravanan, Vivek, Dutta, Souham, Pichon, Martin, Leclerc, Cedric, Guemene, Alexis-Scott

Thermal Management Control Strategy for Primary & Secondary Drive Cooling Hybrid Electric Tractor

2026-26-0069

1/16/2026

Global emission norms are getting very strict due to combat the harmful pollutants from internal combustion engine. Hence internal combustion engine (ICE)-based agricultural tractors need to introduce complex after-treatment systems and fuel optimization to provide same or higher value to farmers as cost of these systems drive the overall cost of the product. Engineers around the world are building Electric vehicles to combat the problem and has range issues due to design constraints & Hybrid tractors have emerged as a promising intermittent solution. It helps in combining the advantages of respective ICE and electrification solutions while reducing overall vehicle emissions and enhances operational flexibility. This paper presents a modular thermal modes system developed for a hybrid electric tractor platform where a downsized diesel engine operates at optimal efficiency DC generator used to charge the battery & DC converter is used to charge the auxiliary battery. Battery which is

K, Sunil, D, Mari, Natarajan, Saravanan, Kumawat, Deepak, rojamanikandan, Arumugham, K, Mala, V, Sridharan, Muniappan, Balakrishnan, Makana, Mohan

Scalable and Modular Data-Driven Hybrid Chassis Dynamometer Framework for EV Powertrain Evaluation

2026-26-0363

1/16/2026

In its conventional form, dynamometers typically provide a fixed architecture for measuring torque, speed, and power, with their scope primarily centered on these parameters and only limited emphasis on capturing aggregated real-time performance factors such as battery load and energy flow across the diverse range of emerging electric vehicle (EV) powertrain architectures. The objective of this work is to develop a valid, appropriate, scalable modular test framework that combines a real-time virtual twin of a compact physical dynamometer with world leading real-time mechanical and energy parameters/attributes useful for its virtual validation, as well as the evaluation of other unknown parameters that respectively span iterations of hybrid and electric vehicle configurations, ultimately allowing the assessment of multiple chassis without having to modify the physical testing facility's test bench. This integration enables a blended approach, using a live data source for now, providing

Kumar, Akhilesh, V, Yashvati

Preventing Thermal Run-Away using Shape Memory Alloy

2026-26-0009

1/16/2026

The present disclosure is about combating Thermal runaway in Electric, Plug-in Hybrids and mild hybrid vehicles. This paper comprises of high-Voltage Battery pack containing Battery cells electrically coupled with Shape Memory Alloy along with Busbars. These connectors (Shape Memory Alloy) are programmed to operate in two states: First to electrically connect the cells with the busbars, second to disconnect the individual cells from electric connection beyond the threshold temperature. This mechanism enables the Battery cells to rapidly prevent the Battery from the Thermal runaway event which is caused from the cell level ensuring the Battery safety mechanically. Additionally, the Battery pack includes the cell monitoring system and Battery Monitoring System to enhance the above invention with regards to the safety of the vehicle. This configuration is implementable and retrofittable into existing battery systems, offering a robust solution to the challenges posed by prolonged vehicle

Reginald, Rini, Rout, Saswat, VENKATESH, Muthukrishnan, Chauhan, Ashish Jitendra, Selvaraj, Elayanila

Integrated Cooling/HVAC System Design and Control Strategy for Light Fuel Cell Electric Vehicle

14-15-01-0002

1/14/2026

In the recent years, the use of conventional passenger vehicles has been increasingly discouraged, from European-level policies to local municipal regulations, due to the urgent need to reduce greenhouse gas emissions and urban pollution. In response to these challenges, the PRIN2020 project HySUM (Hybrid SUstainable Mobility platform) explores innovative hybrid powertrain solutions for light and heavy quadricycles to achieve near-zero pollutant emissions, focusing on internal combustion engine hybrid electric vehicles and fuel cell hybrid electric vehicles. Taking all these aspects into consideration, this article proposes an integrated solution for cooling/HVAC circuits, to improve energy efficiency and occupants’ comfort, while focusing on proper battery operation, with a recuperator heat exchanger used to recover the available heat at the powertrain output, in order to reduce the HVAC heater energy consumption. The complexity of the circuit requires a specific control logic to be

Lombardi, Simone, Putano Bisti, Chiara, Federici, Leonardo, Pistritto, Antonino, Chiappini, Daniele, Tribioli, Laura

On Optima Selection Strategies of Adversarial Swarm Learning for Energy Management of PHEVs

2025-01-7320

12/31/2025

Developing robust optimization and learning methods is necessary for intelligent vehicles since an increasing number of critical control functions will be handled by artificial intelligence. This paper proposes an adversary swarm learning (ASL) system and an optima selection strategy for robust energy management of plug-in hybrid electric vehicles (PHEVs). The proposed ASL system comprises an attacking swarm and a defending swarm, which compete against each other iteratively to derive the most robust equivalent consumption minimization strategy (ECMS) for PHEV energy management. During the attacking rounds, the ECMS settings are fixed by the defender. Meanwhile, the attacker generates worst-case driving conditions by training a model in order to Maximize the equivalent energy consumption. During the defending rounds, the ECMS settings are optimized by the defender based on the driving scenarios generated by the attacker. The settings of robust ECMS are derived by introducing the

Zhong, Danyang, Yu, Zhuoping, Xiong, Lu, Zhou, Quan

Electrification: Vol. 3

EPRCOMPV042025

12/29/2025

Muelaner, Jody Emlyn, Adas, Camilo Abduch, Xu, Min, Zhang, Yijia

A Comparative Lifecycle Assessment Framework for Automotive Battery Storage Systems

13-07-01-0001

12/19/2025

The transportation sector faces heightened scrutiny to implement sustainable technologies due to market trends, escalating climate change and dwindling fossil fuel reserves. Given the decarbonization efforts underway in the sector, there are now rising concerns over the sustainability challenges in electric vehicle (EV) adoption. This study leverages ISO 14040 Lifecycle Assessment methodology to evaluate EVs, internal combustion engine vehicles (ICEVs), and hybrid electric vehicles (HEVs) spanning cradle-to-grave lifecycle phases. To accomplish this an enhanced triadic sustainability metric (TSM) is introduced that integrates greenhouse gas emissions (GHG), energy consumption, and resource depletion. Results indicate EVs emit approximately 29% fewer GHG emissions than ICEVs but about 4% more than HEVs on the current the US grid, with breakeven sustainability achieved within a moderate mileage range compared to ICEVs. Renewable energy integration on the grid significantly enhances EV

Koech, Mercy Chelangat, Fahimi, Babak, Balsara, Poras T., Miller, John

Optimizing Automotive Software Development for Hybrids through the V-Model Integrated with Functional Design and In-the-Loop Validation (SiL/HiL)

2025-36-0249

12/18/2025

This paper presents a comprehensive analysis of advanced methods for optimizing software development in hybrid vehicles, focusing on the V-Model methodology integrated with Model-Based Systems Engineering (MBSE), functional design techniques and In-the-Loop validation processes, and the incorporation of agile methodologies such as SAFe (Scaled Agile Framework). The increasing complexity of embedded systems in hybrid vehicles, driven by electrification and the introduction of autonomous and connected systems, demands systematic and rigorous approaches to ensure reliability, safety, and energy efficiency. Over the next sections, we will explore the fundamental principles of the V-Model, its adaptations to the context of hybrid vehicles, the implementation of functional design processes supported by MBSE, the application of Software-in-the-Loop (SiL) and Hardware-in-the-Loop (HiL) methodologies for system validation, and finally the integration of agile SAFe principles to manage

Gomes, Cleber Willian, Natal, Icarus Lima

Braking systems for electrified vehicles in national market

2025-36-0077

12/18/2025

The demand for electrified vehicles has been increasing over the last few years, near to 180 thousand units were sold only in 2024, which represented around 7% of total sales of this type of vehicle in Brazil. By the year 2030, it is expected that at least 40% of sales volume will be electrified vehicles, considering mild hybrids. These results show that vehicle manufacturers are moving towards electrification and reducing carbon emission rates. Different levels of electrification are applied in their portfolio: from mild hybrid or rechargeable vehicles to fully electric vehicles. When analyzing the number of components in each automotive system, it is possible to notice a huge reduction. Electric vehicles have 90% fewer moving parts in the engine than combustion vehicles. In brake systems, the reduction can be up to 20% in hybrid and electric vehicles, which can use the same solutions. This paper aims to present the changes in the sets of braking components from combustion vehicles to

Romão, Bruno, Batagini, Emerson, Horschutz, Everton

Items per page:

1 – 50 of 3167