Browse Topic: Off-board energy sources

Items (3,013)
This paper proposes a theoretical drive cycle for the competition, considering the battery pack project under design. The vehicle has a non-reversible, double-stage gear train, created without a dynamic investigation. To evaluate the effect on performance, several ratios were analyzed. Dynamic model uses Eksergian’s Equation of Motion to evaluate car equivalent mass (generalized inertia), and external forces acting on the vehicle. The circuit is divided into key locations where the driver is likely to accelerate or brake, based on a predicted behavior. MATLAB ODE Solver executed the numerical integration, evaluating time forward coordinates, creating the drive cycle. Linear gear train results provided data as boundary conditions for a second round of simulations performed with epicyclic gear trains. Model is updated to include their nonlinearity by differential algebraic equation employment with Lagrange multipliers. All data undergoes evaluation to ascertain the mechanical and
Rodrigues, Patrícia Mainardi TortorelliSilveira, Henrique Leandro
Nestled in the Himalayas, the Kingdom of Bhutan demonstrates a strong commitment to sustainability and environmental conservation, guided by its constitution and the philosophy of Gross National Happiness (GNH). This commitment is underpinned by policies in conservation, waste management, and energy practices. Despite efforts to promote clean energy, Bhutan relies heavily on non-renewable sources—coal, biomass, and petroleum—accounting for 62.4% of its energy mix, while hydropower, wind, and solar contribute 37.6%. The government has introduced initiatives like the “Low Emission Development Strategy” and the “EV Roadmap 2035” to encourage electric vehicle (EV) adoption. However, the transport sector consumes over 108,768.10 KTOE (14.4% of total energy use), with vehicle sales rising at a CAGR of 6.7% from 75,190 in 2014 to 126,650 in 2023. Yet, only 0.36% of these vehicles are electric, while others contributing to 60.01% of the country's carbon dioxide emissions. By referencing
Wangchuk, SingyeDema, Dorji
Adoption of Electric Vehicles (EVs) reduces air pollution by reducing harmful gas emissions. Such adoption, however, needs a reliable and convenient charging infrastructure, including smart EV charging. Renewable energy sources such as solar photovoltaic cells, battery and wind energy systems can address these infrastructural gaps which work in conjunction with main grid power supply thereby providing low-cost electricity. This paper introduces an energy management algorithm for integrated renewable and grid power sources available at charging stations across India that considers techno-economic and environmental factors. The current work proposes a supervisory controller model that manages the load power demand of the charging station. The controller effectively deploys low cost energy sources based on the status of all available power supplies and reduces the overall charging costs in real time. The energy management algorithm ensures adequate stand-alone energy generation and
Shukla, AnkitKushwah, Yogendra SinghSuman, Saurabh
ABSTRACT The electrical power demands of military ground vehicles have grown rapidly over the years. New sensors, computers, communications equipment, and weapon systems demand increased levels of electrical power to employ their capabilities. To provide our War-fighters access to these new technologies, vehicle power initiatives are keeping pace by exploring efficient integrated next-generation mobile power solutions. TARDEC’s Advanced Propulsion with Onboard Vehicle Power (APOP) program and explorations into on-platform Directed Energy based systems demonstrate an ideal coupling of compliment technologies. The advanced warfare capabilities of the future can be brought to our Warfighters through purposeful research and investment to ensure timely readiness. The TARDEC/GDLS APOP power generation effort is one such collaborative effort, and represents a potential breakthrough in next-generation power for military ground vehicles
Pesch, Kurt I.Boice, Kevin J.
ABSTRACT Non-thermal plasma-assisted partial oxidation of hydrocarbon fuels (including military logistic fuels) is considered with the intent to rapidly produce hydrogen-rich syngas with the least amount of electrical power. The syngas produced can be used to fuel quiet solid oxide fuel cell (SOFC) auxiliary generators, be added to engines or combustors to extend lean operation (decrease NOx and increase efficiency) or be further reformed to increase hydrogen yield (via water-gas shift and gas cleanup) for low-temperature fuel cells. Unlike catalytic fuel reformers that suffer from adverse issues involving catalyst deactivation (coking and tolerance to sulfur) and require a warmup period dependent on the thermal mass of the catalyst, plasma reforming offers a non-catalytic approach for rapid “on-demand” hydrogen-rich syngas production (quick startup). Plasma fuel reforming is also fuel flexible and can be applied to applications needing dynamic control of a varying amount of syngas
Pearlman, HowardSchwartz, BrianDemydovych, MaxChen, Chien-HuaRabinovich, AlexanderShenoy, ShridharFridman, Alexander
ABSTRACT An efficient and collaborative process for the realization and implementation of an electrical power management strategy for a modern military vehicle is demonstrated. Power, software and hardware engineers working together and using simulation and emulation tools are able to develop, simulate and validate a power strategy before prototype vehicle integration, reducing integration cost and time. For demonstration, an intelligent electrical power management strategy is developed for a generic military vehicle with conventional engine/transmission propulsion and an inline generator. The challenge of this architecture is maintaining electrical bus stability/regulation at low engine speed given that electrical power demands may exceed power supplied. The intelligent electrical power management strategy presented limits the total power demand to power available by overriding the demands of the individual loads. Based on load prioritization and vehicle system dynamics, power limits
Kelly, John W.Sadler, RyanHaynes, AricRose, Gary
ABSTRACT Situations exist that require the ability to preposition a basic level of energy infrastructure. Exploring and developing the arctic’s oil potential, providing power to areas damaged by natural or man-made disasters, and deploying forward operating bases are some examples. This project will develop and create a proof-of-concept electric power prepositioning system using small autonomous swarm robots each containing a power electronic building block. Given a high-level power delivery requirement, the robots will self-organize and physically link with each other to connect power sources to storage and end loads. Each robot mobile agent will need to determine both its positioning and energy conversion strategy that will deliver energy generated at one voltage and frequency to an end load requiring a different voltage and frequency. Although small-scale robots will be used to develop the negotiation strategies, scalability to existing, large-scale robotic vehicles will be
Weaver, Wayne W.Mahmoudian, NinaParker, Gordon G.
ABSTRACT The M109A7 Self-Propelled Howitzer (SPH) developed by BAE Systems is groundbreaking for its utilization of 610 Vdc high-voltage (HV) electrical power generation and distribution. When the vehicle entered development ten years ago, silicon based power conversion devices were a proven and effective technology to provide the demanding power needs of the new military platform. Since then, technological advances in Silicon Carbide (SiC) semiconductors have shown great promise in providing significant improvements to power density, efficiency, and operating temperature. When GE Aviation developed a prototype Silicon Carbide power converter which debuted at the 2014 GVSET Symposium, both TARDEC and BAE Systems, P&S recognized the benefit to evaluating and demonstrating the technology on the M109A7. In August 2016, the plan came to fruition when the joint TARDEC, BAE Systems P&S, and GE Aviation team successfully completed a series of demonstration tests showing that the technology
Miller, Mark R.Brinton, GordonRoden, GareyHamilton, GeorgeJochum, EricEddins, RichardMilford, ChristineShiver, Richard
ABSTRACT This paper explores the effect dispatchable loads have on microgrids with a high penetration of renewable sources. For this study, the dispatchable loads are electric vehicles whose state of charge must be maintained on a 24 hour cycle. Simulation and optimization tools are utilized in MATLAB to optimize a grid design with 50% renewable energy sources in the form of a photovoltaic solar array. The findings of this study are that the electric vehicle dispatchable loads can be used to stabilize a microgrid against unpredictable losses in renewable generation
Bordeau, KyleParker, GordonVosters, GregoryWeaver, WayneWilson, DavidRobinett, Rush D.
ABSTRACT This paper describes next generation modeling tools to solve a basic problem of concept analysis, which is the lack of component models that realistically estimate the performance of technology that has yet to be fully reduced to specific products. Three important classes of electric power components essential to future Army vehicles are addressed: integrated electric machines, battery energy storage, and traction motor drives. Behavior models are delivered in a common software simulation “wrapper” with a limited number of user settings that allow the ratings of the component to be scaled to the performance required by the vehicle concept represented in a larger simulation. This approach captures expert knowledge about components so the systems engineer managing the concept analysis can create reliable simulations quickly
Mazzola, Michael S.Molen, G. MarshallPhillips, StephenYoung, MatthewBillberry, CharlesCard, AngelaGafford, JamesKramer, DenisePozolo, Michael
ABSTRACT With the development of the next generation of military vehicles, the demand for significant amounts of electrical power is increasing, making the design of electrical machines, such as the vehicle alternator, integral to the powertrain design. This shows the importance of the machines’ size and efficiency, and the great influence they will have on the vehicle powertrain design process. In this paper, a finite-element-based scaling technique, capable of quickly generating torque-speed curves and efficiency maps for new machine designs, is improved to have two dimensional scaling factors instead of scaling the dimensions uniformly, thus increasing the flexibility of the tool. First, a magnetostatic finite-element-analysis (FEA) is conducted on a base machine, producing data such as torque, flux linkage, and demagnetizing field intensity in the permanent magnets, over a wide range of current magnitudes and phase angles. Then, based on the dimensional and winding scaling factors
Wang, YuanyingHofmann, HeathIvanco, AndrejRizzo, Denise
ABSTRACT As new subsystems are integrated onto existing ground combat vehicle platforms for capability enhancement purposes, the demand for electrical power output increases. In many cases these enhancements exhaust the available output power reserves and leads to performance capability plateau for some of the existing power systems. This increased power demand may sometimes cause the vehicle’s generator to become fully loaded, causing any energy shortfalls to be covered by the battery storage system. When a high percentage of system power is routinely provided by the battery system without optimized battery management, the result is degraded battery capacity that leads to frequent battery replacement. This paper addresses specific limitations of ground combat vehicle power systems related to insufficient power output capacity and deficient battery management practices. Additionally, the paper will discuss concepts that enhance battery management capability and extend the operational
Palmer, JasonHamilton, GeorgeSmith, MichaelWright, Ronnie L.
ABSTRACT A sudden increase in microgrid electrical power consumption requires the fast supply of energy from different generating sources to guarantee microgrid voltage stability. This paper presents the results of simulations investigating the integration of an electric supercharger into a Heavy Duty Diesel (HDD) genset connected to a microgrid for reducing engine speed droop in response to an abrupt power demand requested from the grid. First, a mean value model for the 13 L HDD engine is used to study the response of the baseline turbocharged engine during a fast load increase at low engine speed. The limited air mass in the cylinder during the transient results in engine lugging and ultimately engine stall. Then, an electrical supercharger is integrated before the turbocharger compressor to increase the engine air charge. During steady state operation, the simulation results indicate that the supercharger is able to increase the air-charge by approximately 50% over the lower half
Salehi, RasoulMartz, JasonStefanopoulou, AnnaRizzo, DeniseMcGrew, DeanHansen, Taylor
ABSTRACT With the increase in electric power on military ground vehicle platforms, electrically driven accessories are replacing existing hydraulic, belt, and gear-driven loads. Permanent Magnet Synchronous Machines (PMSM) are often selected to drive these accessories, and are under consideration for the main engine generator, due to their torque density and efficiency being among the highest available. To maximize the efficiency of a PMSM, accurate knowledge of its parameters is required across the entire operating range. Efficient control of the onboard electric drives will help reduce fuel consumption in the ground vehicle fleet. This paper presents the effects of iron saturation on the performance of a PMSM drive. Iron saturation depends on the amount of current injected into the motor and it restricts the amount of flux linkage that can be generated. PMSMs are controlled using a two axis space vector representation. Ideally, the control is decoupled, such that the flux linkage
Cintron-Rivera, Jorge G.Foster, Shanelle N.Zanardelli, Wesley G.Strangas, Elias G.
ABSTRACT Military ground vehicles need greater electrical power generation to address continually increasing power demands due to various loads, e.g. advanced communications equipment, jamming equipment, electronic armor, and electronic weapons system. More electrical power is also required for electrification of auxiliary systems (steering, cooling fans, HVAC, and pumps) to improve system efficiency - currently driven mechanically. Electrical equipment can be powered from the 600 volt DC bus power supply or from the conventional 28 volt DC bus depending on size, cost, weight, cooling, performance, and cooling impact. Appropriate power electronics converters (dc to dc, ac to dc, dc to ac) are used to manipulate the DC source to drive equipment on the Stryker APOP electrical system. These devices are highly efficient and should lead to the reduction of parasitic losses. With the above in perspective, the US Army RDECOM-TARDEC, GVPM (Ground Vehicle Power and Mobility) has been pursuing
Masrur, M. AbulBoice, Kevin J.Rizzo, Denise M.Monroe, John W.Tylenda, Joshua S.McGrew, Dean Z.
ABSTRACT Military Ground Vehicle electric power demands continue to grow as new mission equipment is added. Using an Auxiliary Power Unit (APU) consumes less fuel than restarting the main engine frequently to charge batteries. To meet the rising demand for powerful, L-3 Combat Propulsion Systems is developing a family of heavy-fuel rotary engines. Rotary engines offer superior power density making them a good choice for applications that require high power in a limited space. Heavy fuel capability simplifies logistical challenges in the field. However, rotary engines have unique cooling challenges. Unlike a piston engine, the intake, compression, expansion, and exhaust events all take place at their respective fixed positions around the circumference of the rotor housing, leading to large temperature differences around the housing. The cooling system must be carefully developed to minimize these temperature differences in an effort to control thermal deformation, minimize thermal
Lee, KevinOehlerking, DaleRoodvoets, Levi
ABSTRACT Electrical power system upgrades needed to fulfill mission objectives for next generation vehicles will require technology advances such as greater power density, increased functionality, and higher operating temperature. To meet these requirements, electrical power demands will exceed the capabilities of currently available low voltage power systems. High Voltage DC (HVDC) systems, e.g., 270 – 800 VDC, are being considered to meet next generation vehicle requirements, but these electrical power systems have the potential for extremely large fault currents in case of electrical equipment failure. Improved battery safety and intelligent Solid State Circuit Breakers (SSCB) and Solid State Power Controllers (SSPC) are needed to improve mission effectiveness, reliability, and personnel safety of next generation military and commercial ground, air, and sea vehicle electrical power systems. In this paper we present three enabling technologies developed by Creare: (1) an intelligent
Pilvelait, BruceCameron, BenRentel, CarlosFogg, DavidFinger, Bill
It’s common knowledge that a major challenge for solar energy is how to store excess energy produced when conditions are right, like noon-time sun, so that it can be used later. The usual answer is batteries. But renewable energy resources are causing problems for the electricity grid in other ways as well. In a warm, sunny location like California, mid-afternoon had been a time of peak demand for the electric utility, but with solar it’s now a time of peak output
The Korea Research Institute of Standards and Science (KRISS) has developed a metamaterial that traps and amplifies micro-vibrations in small areas. This innovation is expected to increase the power output of energy harvesting, which converts wasted vibration energy into electricity, and accelerate its commercialization
In the future, power sockets used to recharge smartphones, tablets, and laptops could become obsolete. The electricity would then come from our own clothes. By means of a new polymer that is applied on textile fibers, clothing could soon function as solar collectors and thus as a mobile energy supply
This document provides recommended best practice methods and processes for the in-service inspection, evaluation and cleaning of all physical contact (PC) fiber optic interconnect components (termini, alignment sleeves and connectors), test equipment and test leads for maintainers qualified to the approved aerospace fiber optic training courses developed in accordance with ARP5602 or ARINC807. This document also provides a decision-making disposition flowchart to determine whether the fiber optic components are acceptable for operation. For definitions of individual component parts refer to ARP5061
AS-3 Fiber Optics and Applied Photonics Committee
As the U.S. military embraces vehicle electrification, high-reliability components are rising to the occasion to support their advanced electrical power systems. In recent years, electronic device designers have started using wide band-gap (WBG) materials like silicon carbide (SiC) and gallium nitride (GaN) to develop the semiconductors required for military device power supplies. These materials can operate at much higher voltages, perform switching at higher frequencies, and feature better thermal characteristics. Compared to silicon, SiC-based semiconductors provide superior performance. The growing availability of these materials, in terms of access and cost, continues to encourage electrification. With the ever-present pressure of size, weight, and power (SWaP) optimization in military applications, and a desire to keep up with the pace of innovation, there's a need for capacitors that can deliver higher power efficiency, switching frequency, and temperature resistance under harsh
Mitigating environmental impacts is ever more crucial as wind energy technology expands to help meet the Nation’s goal of achieving a carbon pollution-free power sector by 2035 and net zero emissions economy by no later than 2050
Transportation contributes 27% of the greenhouse gas emissions in the US. Governments worldwide are developing new programs to hasten the adoption of electric vehicles (EVs) in the transition to zero-emission vehicles. However, the success of EV adoption generally depends on user preferences. This study explores what we can find out about consumer preferences while accounting for unobserved heterogeneity. Consumer choices for EVs, including plug-in EVs (PEVs) and fuel-cell EVs (FCEVs), are analyzed using the California Vehicle Survey (2019) data. Several factors are examined, including the availability of clean source energy (installed solar panels) at home, preferable location for recharging PEVs, past driving experience with EVs, availability of public charging infrastructure, and sociodemographic factors. A mixed multinomial (random parameter) logit model is estimated, exploring the associations between the selected variables and EV consumer preferences while accounting for
Moradloo, NastaranMahdinia, ImanKhattak, Asad
Sustainable mobility is a pressing challenge for modern society. Electrification of transportation is a key step towards decarbonization, and hydrogen Fuel Cell Hybrid Electric Vehicles (FCHEVs) offer a promising alternative to Battery Electric Vehicles (BEVs), especially for long-range applications: they combine a battery system with a fuel cell, which provides onboard electric power through the conversion of hydrogen. Paramount importance is then given to the design and sizing of the hybrid powertrain for achieving a compromise between high performance, efficiency, and low cost. This work presents a Hardware-in-the-Loop (HIL) platform developed for designing and testing the powertrain layout of an FCHEV. The platform comprises two systems: a simulation model reproducing the dynamics of a microcar and a hardware system for the fuel cell hybrid electric powertrain. The former simulates the vehicle's behavior, while the latter is composed of a 2kW real fuel cell stack and a 100Ah Li-ion
Bartolucci, LorenzoCennamo, EdoardoCordiner, StefanoDonnini, MarcoGrattarola, FedericoMulone, Vincenzo
The aim of paper is to present the workflow of battery sizing for electric L7e-CU type vehicle. The intention is to use it as last-mile delivery multi-purpose vehicle. Based on legislation limits and pursuing the real-world driving cycle, major vehicle characteristics as total vehicle mass including payload and wheel size are determined. Vehicle total energy consumption is calculated knowing vehicle power in time. Accordingly, to selected gearbox ratio the electric motor nominal power-speed curve is defined as well as the nominal torque-speed curve. Applying vehicle acceleration dynamics involving limits considering resistive forces, acting on the vehicle, e.g. slope, friction, air drag, and total inertia, referred to the electric motor through the gearbox the electric motor over-load-ability characteristics are calculated. Next, the motor design is defined and optimized. Defining required vehicle range at given driving cycle and knowing the vehicle and all powertrain characteristics
Rupnik, UrbanVukotić, MarioManko, RomanAlić, AlenČorović, SelmaMiljavec, Damijan
Even if huge efforts are made to push alternative mobility concepts, such as, electric cars (BEV) and fuel cell powered cars, the importance and use of liquid fuels is anticipated to stay high during the 2030s. The biomethane and synthetic natural gas (SNG) might play a major role in this context as they are raw material for chemical industry, easy to be stored via existing infrastructure, easy to distribute via existing infrastructure, and versatile energy carrier for power generation and mobile applications. Hence, biomethane and synthetic natural gas might play a major role as they are suitable for power generation as well as for mobile applications and can replace natural gas without any infrastructure changes. In this paper, we aim to understand the direct production of synthetic natural gas from CO2 and H2 in a Sabatier process based on a thermodynamic analysis as well as a multi-step kinetic approach. For this purpose, we thoroughly discuss CO2 methanation to control emission in
Mauss, Fabian
The U.S. Army initiated a shift towards electrifying and hybridizing its tactical vehicle fleet in alignment with its Climate Strategy and global automotive trends. Survey findings indicate a general desire by soldiers for the ability to opportunity charge electrified tactical vehicles, especially in austere locations, with a focus on solar recharging. This study extracts, cleans, and analyzes geo-location data from a training exercise at the National Training Center at Fort Irwin, CA to identify the drive cycles for over 400 tactical vehicles. These drive cycles were then used to estimate the energy consumption per vehicle. The analysis then identifies how much energy can be provided by a 300 W solar blanket, deployed when a vehicle is stationary. The study found that the 300 W solar blanket under ideal conditions could offset approximately 10 percent of the energy required by the average vehicle. As such, solar energy has the potential to be useful for providing small amounts of
Mittal, VikramMuraco, JohnKonopa, BridgetMayfield, LoganCrocker, MatthewRevnew, LukeMiller, Mark
Rolling bearings play a critical role in rotating machinery, with their fatigue life directly impacting equipment’s operational reliability. This underscores the significant engineering application value of “fault diagnosis” (FD) technology for rolling bearings in mechanical, automation, and aerospace domains. Literature reviews highlight that a substantial portion of failures in machinery such as jet turbine engines, wind turbines, gear reducers, and induction machines are attributable to bearing issues. Early fault detection and preventive maintenance are therefore imperative for ensuring the smooth operation of rotating machinery. This paper focuses on rolling bearings, delving deep into FD technology using machine learning principles. It analyses the structure and common failure modes of rolling bearings, discussing an FD method based on machine learning. Specifically, the SE-DRN (“squeeze-exclusion deep residual network”) approach is employed, leveraging “variational modal
Muin, Abdullah-AlKhan, ShahrukhMiah, Md Helal
Penn Engineers have developed a new chip that uses light waves, rather than electricity, to perform the complex math essential to training AI. The chip has the potential to radically accelerate the processing speed of computers while also reducing their energy consumption
To expand the availability of electricity generated from nuclear power, several countries have started developing designs for small modular reactors (SMRs), which could take less time and money to construct compared to existing reactors
The ongoing transition from fossil fuels to renewable energy sources has never been more important as climate change and sustainability awareness continue to rise
Solar panels are an increasingly popular way to generate electricity from the sun’s energy. Although humans are still figuring out how to reliably turn that energy into fuel, plants have been doing it for eons through photosynthesis. Now, a team reporting in ACS Engineering Au has mimicked the process to produce methane, an energy-dense fuel, from carbon dioxide, water and sunlight. Their prototype system could help pave the way toward replacing nonrenewable fossil fuels
Reducing dust accumulation on any surface is key for lunar missions as dust can damage or impair the performance of everything from deployable systems to solar cells on the Moon’s surface. Electrodynamic dust shields (EDSs) are a key method to actively clean surfaces by running high voltages (but low currents) through electrodes on the surface. The forces generated by the voltage efficiently remove built up, electrically charged dust particles. Innovators at the NASA Kennedy Space Center have developed a new transparent EDS for removing dust from space and lunar solar cells among other transparent surfaces
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