Browse Topic: Electric power

Items (2,095)
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 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 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
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 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 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 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 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 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 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 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 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 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
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
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
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
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
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
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
The automotive PowerNet is in the middle of a major transformation. The main drivers are steadily increasing power demand, availability requirements, and complexity and cost. These factors result in a wide variety of possible future PowerNet topologies. The increasing power demand is, among other factors, caused by the progressive electrification of formerly mechanical components and a constantly increasing number of comfort and safety loads. This leads to a steady increase in installed electrical power. X-by-wire systems1 and autonomous driving functions result in higher availability requirements. As a result, the power supply of all safety-critical loads must always be kept sufficiently stable. To reduce costs and increase reliability, the car manufacturers aim to reduce the complexity of the PowerNet system, including the wiring harness and the controller network. The wiring harness e.g., is currently one of the most expensive parts of modern cars. These challenges are met with a
Jagfeld, Sebastian Michael PeterWeldle, RichardKnorr, RainerFill, AlexanderBirke, Kai Peter
With the COP28 decisions the world is thriving for a future net-zero-CO2 society and the and current regulation acts, the energy infrastructure is changing in direction of renewables in energy production. All industry sectors will extend their share of direct or indirect electrification. The question might arise if the build-up of the renewables in energy production is fast enough. Demand and supply might not match in the short- and mid-term. The paper will discuss the roadmaps, directions and legislative boundary parameter in the regenerative energy landscape and their regional differences. National funding on renewables will gain an increasing importance to accelerate the energy transformation. The are often competing in attracting the same know-how on a global scale. In addition the paper includes details about energy conversion, efficiency as well as potential transport scenarios from production to the end consumer. Technologies are compared in respect of their TLR level and
Rothbart, Martin
Dynamic wireless charging (DWC) systems can make up electrified roads (eRoads) on which electricity from the grid is supplied to electric vehicles (EVs) wirelessly while the EVs travel along the roads. Electrification of roads contributes to decarbonizing the transport sector and offers a strong solution to high battery cost, range anxiety, and long charging times of EVs. However, the DWC eRoads infrastructure is costly. This article presents a model to minimize the infrastructure cost so that the deployment of eRoads can be economically more feasible. The investment for eRoad infrastructure consists of the costs of various components including inverters, road-embedded power transmitter devices, controllers, and grid connections. These costs depend on the traffic flow of EVs. The configuration and deployment strategy of the proposed eRoads in Southeastern Canada are designed with optimized charging power and DWC coverage ratio to attain the best cost-effectiveness. Well-designed
Qiu, KuanrongRibberink, HajoEntchev, Evgueniy
A new electrical power converter design achieves a much higher efficiency at lower cost and maintenance than before. The direct current voltage boost converter is poised to be a significant contribution to the further development of improved electric and electronic components for healthcare devices
The purpose of the Air Generation System is to provide a constant supply of conditioned fresh air to meet the necessary oxygen availability and to prevent CO2 concentrations for the occupants in an aircraft. The engine bleed energy or electrical load energy consumed towards this circumstance accounts to be approximately 5% of total fuel burn and in turn, contributes to the global emissions of greenhouse gases. This paper studies the improvement areas of the present conventional system such as fuel burn consumption associated with an aircraft ECS depending on the amount of bleed, ram air usage and electric power consumption. Improved systems for sustainability and hybridization in environmental control systems are desirable in aircraft. This paper explains how a new design of the sustainable hybrid module assists the conventional system, by using a proposed modular MPBR. The MPBR system generates oxygen-enriched air, which is mixed with the traditional fresh air generated from
Subrahmanya, ShreeshaKumar, NaveenRanjan, JayantKotnadh, Shivaprasad
The present study was motivated by a need to expand information for consumers offered through the FuelEconomy.Gov website. To that end, a power-based modeling approach has been used to examine the effect of steady-speed driving on estimated range for model year 2020 – 2023 battery electric vehicles (BEVs). This approach allowed rapid study of a broader range of BEV models than could be accomplished through vehicle tests. Publicly accessible certification test results and other data were used to perform a regression between cycle-average tractive power requirements and the resulting electrical power. This regression enabled estimation of electric power and energy use over a range of steady highway speeds. These analyses in turn allowed projection of vehicle range at differing speeds. The projections agree within 6% with available 65 MPH manufacturer test data. Analyses of vehicles from model years 2020 – 2023 show that the 5-cycle range and energy use values from the window stickers of
Sluder, C. ScottDavis, Stacy C.Boundy, Robert G.
This Electric Road System was devised that would provide electric power to EVs directly from the infrastructure so that EVs could undergo intermittent charging while driving. This system is a conductive dynamic charging system that operates from the side of the vehicle (roadside), and research has been underway on the application of this approach to passenger cars and race cars. This paper focused on resolving issues with freight vehicles, which account for most of the CO2 emissions in the transportation sector. This Electric Road System that operates by contact from the roadside was applied to heavy-duty trucks, which have been considered a challenge to convert to EVs, and at the same time the infrastructure technology was also expanded and evolved. And verification tests using actual vehicles were conducted for regenerative energy absorption control of a charging vehicle while driving. The results confirmed that this control system appropriately controls the distribution of power
Tajima, TakamitsuAbe, Hiroyuki
Opposed piston two-stroke (OP2S) diesel engines have demonstrated a reduction in engine-out emissions and increased efficiency compared to conventional four-stroke diesel engines. Due to the higher stroke-to-bore ratio and the absence of a cylinder head, the heat transfer loss to the coolant is lower near ‘Top Dead Center.’ The selection and design of the air path is critical to realizing the benefits of the OP2S engine architecture. Like any two-stroke diesel engine, the scavenging process and the composition of the internal residuals are predominantly governed by the pressure differential between the intake and the exhaust ports. Without dedicated pumping strokes, the two-stroke engine architecture requires external devices to breathe. In the unique OP2S engine architecture studied in this work, the external pumping devices present in the air path include an electrically assisted turbocharger (EAT), an electrified EGR pump, and a back-pressure valve (BPv) located downstream of the
Bhatt, AnkurGandolfo, JohnHuo, MingGainey, BrianLawler, Benjamin
Toyota has developed a new 2.4L L4 turbo (2.4L-T) engine with 8AT and 1-motor hybrid electric powertrains for midsize pickup trucks. The aim of these powertrains is to fulfill both strict fuel economy and emission regulations toward “Carbon Neutrality”, while exceeding customer expectations. The new 2.4L L4 turbocharged gasoline engine complies with severe Tier3 Bin30/LEVIII SULEV30 emission regulations for body-on-frame midsize pickup trucks improving both thermal efficiency and maximum torque. This engine is matched with a newly developed 8-speed automatic transmission with wide range and close step gear ratios and extended lock-up range to fulfill three trade-off performances: powerful driving, NVH and fuel economy. In addition, a 1-motor hybrid electric version is developed with a motor generator and disconnect clutch between the engine and transmission. This hybrid architecture provides EV driving, which enhances the NVH and fuel economy, and provides additional acceleration with
Endo, MotoshiroBridge, AlistairIkeda, AkihiroMiyamoto, KoichiMiyazaki, TerufumiHosoda, FuminoriHerring, CraigWallace, James J.Hu, Mu
The 2023 FISITA White Paper (for which the author was a contributor) on managing in-service emissions and transportation options, to reduce CO2 (CO2-e or carbon footprint) from the existing vehicle fleet, proposed 6 levers which could be activated to complement the rapid transition to vehicles using only renewable energy sources. Another management opportunity reported here is optimizing the vehicle’s life in-service to minimize the life-cycle CO2 impact of a range of present and upcoming vehicles. This study of the US vehicle fleet has quite different travel and composition characteristics to European (EU27) vehicles. In addition, the embodied CO2 is based on ANL’s GREET data rather than EU27 SimaPro methodology. It is demonstrated that in-service, whole-of-life mileage has a significant influence on the optimum life cycle CO2 for BEVs and H2 fuelled FCEVs, as well as ICEs and PHEVs. Thus, the object is to show how much present, typical in-service life-mileage differs from the
Watson, Harry C.
Bhutan is a small nation in the eastern Himalayas, between two of the world's largest neighbors and fastest-growing economies; China, and India. The GDP of the country is $2.707 Billion as of 2022. Bhutan’s largest renewable source is hydropower, which has a known potential of 30,000 MW. However, it has only been able to harvest only 1,480 MW (5% of the potential). The current overall electrification rate is 99% overall with 98.4% in rural areas. It exports 75.5% of total electricity generated in the country to India. However, the reliable supply of electricity remains a big challenge. The government is also pushing the use of renewable energy sources like solar and wind to diversify the energy mix and enhance the power security of the country. The share of renewable energy is very minimal at present amounting to 723 kW Solar PV and 600 kW Wind power. Bioenergy in the form of fuel wood, energy crops & crop residues, and cattle dung has great potential in the country as the country’s
Wangchuk, SingyeKumar, Naveen
Researchers at the U.S. Department of Energy’s (DOE) Argonne National Laboratory have invented and patented a new cathode material that replaces lithium ions with sodium and would be significantly cheaper. The cathode is one of the main parts of any battery. It is the site of the chemical reaction that creates the flow of electricity that propels a vehicle
The electric power sector accounts for about 30 percent of U.S. emissions of carbon dioxide
Airborne compression-ignition engine operations differ significantly from those in ground vehicles, both in mission requirements and in operating conditions. Unique challenges exist in the aviation space, and electrification technologies originally developed for ground applications may be leveraged to address these considerations. One such technology, electrically assisted turbochargers (EATs), have the potential to address the following: increase the maximum system power output, directly control intake manifold air pressure, and reignite the engine at altitude conditions in the event of an engine flame-out. Sea-level experiments were carried out on a two-liter, four-cylinder compression-ignition engine with a commercial-off-the-shelf EAT that replaced the original turbocharger. The objective of these experiments was to demonstrate the technology, assess the performance, and evaluate control methods at sea level prior to altitude experimentation. This work covers the baseline
Pope, AaronKim, KennethSchroen, ErikClerkin, PeterMusser, MarshallMattson, JonathanMeininger, RikGibson, JosephKang, Sang-GukKruger, KurtHepp, KyleKweon, Chol-Bum
Since the early days of aviation, when an AC-type generator became a primary source of electrical power for all aircraft systems, the demand for electrical power has steadily grown. Following rapid technology and scientific advancements in the aerospace industry, the complexity and criticality of all aircraft systems have increased to the point where multiple independent and isolated electrical power sources are required. In such an environment, with two or more variable-frequency AC-type generators that can be simultaneously activated to provide electrical power to the aircraft power distribution system, a safe power transfer process becomes a major priority. This means that any two independent aircraft AC power sources with different frequencies or phase angles cannot be connected simultaneously to a common power bus. For this purpose, a power transfer protocol has been developed to prevent any aircraft parallel power sourcing and to provide a reliable AC generator connection to
Novakovic, Neno
Researchers have created electrostatic materials that function even with extremely weak ultrasound, heralding the era of permanent implantable electronic devices in biomedicine. Recent research explores implantable medical devices that operate wirelessly, yet finding a safe energy source and protective materials remains challenging. Presently, titanium (Ti) is used due to its biocompatibility and durability. However, radio waves cannot pass through this metal, necessitating a separate antenna for wireless power transmission. Consequently, this enlarges the device size, creating more discomfort for patients
Storing energy is one of the key challenges for implementing sustainable but intermittent electricity sources like solar and wind. Engineers at Sandia National Laboratories are collaborating with New Mexico-based CSolPower LLC to develop a very affordable method of accomplishing that storage
Electrification of road transport is a critical step towards establishment of a sustainable transport ecosystem. However, a major hindrance to electric mobility is the high cost and weight of the battery pack. Downsizing the battery pack will not only address these issues, but will also reduce embedded emissions due to battery manufacturing. One approach towards reducing battery pack size and still offering the user of electric vehicles similar mobility experiences as in case of conventional vehicles is to set up extensive network of charging or battery swapping stations. Another approach is to provide the vehicle with required energy while it is on the move. However, conventional systems such as overhead line or conducting rails have several disadvantages in the urban environment. One solution that has come up in this regard in recent times is the concept of Electric Roads System (ERS), which involves dynamic wireless power transfer (DWPT) to the vehicles from power transmitters
Sardar, ArghyaPrasad, Mukti
In a rush to move towards a sustainable future, the number of electric vehicles has risen significantly in recent years. With this, the need for power to charge those vehicles has also increased. In any electric vehicle fleet location, there could be many vehicles with different arrival and departure times and energy requirements, which might vary every day. Depending on the geographical location, the available solar energy might differ. The electricity costs might change on an hourly basis. This in total can affect the charging costs. In addition, a non-optimal sizing of the energy components could result in an under-sized system, where the energy demands are not met, or it could result in an over-sized system, where the owner must invest more than required. Based on all the information related to vehicle charging load, electricity charges, energy intensity profile of renewable energy generation like solar and wind, an optimal size of components, operational cost, and investment
Munirajappa, ChandrashekaraShrivastava, HimanshuPrasad P, Shilpa
While many consider electricity a basic human right, there are places where people have never had access to it. Among the United Nations’ Sustainable Development Goals is global access to affordable, reliable, and sustainable energy by 2030. Recently, the U.N. reported that progress in global electrification had slowed due to the challenge of reaching those hardest to reach
Exhaust gas emissions from compression ignition engines are the most hazardous contaminants to human beings as well as the atmosphere. This research work contributes to develop a combined technology that targets the reduction in HC, CO, smoke and NOx emissions collectively without any modification in engine fuel or injection strategy. Slight changes in the exhaust after- treatment system will help in meeting the goal of reduced standards. DOC and SCR devices fitted at the exhaust gas pipe reduces CO, HC, smoke, and NOx emissions produced by the CI engine. A combination of aluminum oxide- cerium oxide and iron oxide are used as SCR and DOC catalysts, whose preparation is done by impregnation method and their performance is tested on a SCR+DOC bed. The injection of aqueous urea solution is varied from 200 ml to 600 ml by intervals of 200 ml at different load conditions. Response parameters for various experiments are predicted using response surface methodology. Utilizing this novel
V, PraveenaR, RajarajeswariStephen, Deborah
Scientists have developed a flexible battery as thin as a human cornea, which stores electricity when it is immersed in saline solution, and which could one day power smart contact lenses. Smart contact lenses are high-tech contact lenses capable of displaying visible information on our corneas and can be used to access augmented reality
To turn an ultra-small component on and off, one requires an actuator — a device that transmits an input, such as electricity, into physical motion. Actuators in small-scale technologies to date have critical limitations; for example, if it's difficult to integrate the actuator into semiconductor electronics, real-world applications of the technology will be limited. An actuator design that operates quickly, has precise on/off control, and is compatible with modern electronics would be immensely useful
Most space satellites are powered by photovoltaic cells that convert sunlight to electricity. Exposure to certain orbit radiation can damage the devices, degrading their performance and limiting their lifetime. University of Cambridge scientists have proposed a radiation-tolerant photovoltaic cell design that features an ultrathin layer of light-absorbing material
Electrification of off-road vehicle powertrains can increase mobility, improve energy efficiency, and enable new utility by providing high amounts of electrical power for auxiliary devices. These vehicles often operate in extreme temperature conditions at low ground speeds and high power levels while also having significant cooling airpath restrictions. The restrictions are a consequence of having grilles and/or louvers in the airpath to prevent damage from the operating environment. Moreover, the maximum operating temperatures for high voltage electrical components, like batteries, motors, and power-electronics, can be significantly lower than those of the internal combustion engine. Rejecting heat at a lower temperature gradient requires higher flow rates of air for effective heat exchange to the operating environment at extreme temperature conditions. High airflow rates, coupled with significant airpath restrictions, result in significant cooling power requirements and increased
Sundar, AnirudhVannarath, AshwinPrucka, RobertZhu, QilunKorivi, VamshiRuan, Yeefeng
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