Browse Topic: Capacitors
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
The portable and electric energy storage market has long been dominated by lithium-ion batteries and supercapacitors, surpassing other energy storage systems in their ability to provide higher energy and power. However, in critical applications such as electric vehicles, there is a growing demand for a device that can efficiently produce both high power and high energy over a significant number of cycles. Meeting these rigorous standards presents new challenges for existing technologies, prompting researchers to explore alternative technologies for energy storage devices
Researchers at Drexel University are one step closer to making wearable textile technology a reality. Recently published in the Royal Society of Chemistry’s Journal of Material’s Chemistry A, materials scientists from Drexel’s College of Engineering, in partnership with a team at Accenture Labs, have reported a new design of a flexible wearable supercapacitor patch. It uses MXene, a material discovered at Drexel University in 2011, to create a textile-based supercapacitor that can charge in minutes and power an Arduino microcontroller temperature sensor and radio communication of data for almost two hours
Researchers have developed a low-cost device that can selectively capture carbon dioxide gas while it charges. Then, when it discharges, the carbon dioxide (CO2) can be released in a controlled way and collected to be reused or disposed of responsibly
Micro-supercapacitors could revolutionize the way we use batteries by increasing their lifespan and enabling extremely fast charging. Now, researchers at Chalmers University of Technology have developed a method that represents a breakthrough for how such supercapacitors can be produced
As the electrification of automobiles continues to accelerate, the need for a safe, reliable, high-power energy-storage technology is greater than ever. Ultracapacitors already have an established place in Voltage Stabilization Systems (VSS) for internal-combustion engine (ICE) stop-start applications. By providing additional voltage support during a high-current cranking event, voltage levels are maintained to allow proper operation of accessories without interruption and enable proper operation as battery state-of-health declines
A new bendable supercapacitor made from graphene has been developed that charges quickly and safely stores a record-high level of energy for use over a long period. The technology overcomes the issue faced by high-powered, fast-charging supercapacitors: they usually cannot hold a large amount of energy in a small space
This research aims at developing the suboptimal energy management strategy by using artificial neural network (ANN) for a triple-electrical-energy electric vehicle (EV). The controller hardware designs will be implemented in the future. Firstly, we constructed a low-order dynamic equations that abstracted the characteristics of the vehicle, including energy sources (the fuel cell, lithium battery, and supercapacitor), driver’s model, traction motor, transmission, and longitudinal vehicle dynamics, etc.. The key parameters were mostly retrieved from the commercialization software-Advanced Vehicle Simulator (ADVISOR). Base on the vehicle structure of the Toyota Mirai, we built the range-extended EV. The powertrain system included an 110kW fuel cell set, a 40Ah lithium-ion battery set, and a 165F/48V supercapacitor and a 150kW AC motor. The ECMS control strategy included a six-layer for-loop: the battery state-of-health (SOH), power demand, the battery state-of-charge (SOC??), the
This SAE Recommended Practice is intended as a guide toward standard practice and is subject to change to keep pace with experience and technical advances. It describes a body of tests which may be used as needed for abuse testing of electric or hybrid electric vehicle rechargeable energy storage systems (RESS) to determine the response of such electrical energy storage and control systems to conditions or events which are beyond their normal operating range. This document does not establish pass/fail criteria. However, SAE J2929 does define pass/fail criteria for automotive RESS safety testing. Abuse test procedures in this document are intended to cover a broad range of vehicle applications as well as a broad range of electrical energy storage devices, including individual RESS cells (batteries or capacitors), modules, and packs. RESS includes any type of rechargeable electrical energy storage device, such as batteries and capacitors. This document does not apply to RESS that uses
Capacitors that rapidly store and release electric energy are key components in modern electronics and power systems; however, the most commonly used ones have low energy densities compared to other storage systems like batteries or fuel cells, which in turn cannot discharge and recharge rapidly without sustaining damage. By introducing isolated defects to a type of commercially available thin film in a straightforward post-processing step, a team has demonstrated that a common material can be processed into a top-performing energy storage material
This article presents a two-stage Dynamic Programming (DP)-based approach to solving the problem of Hybrid Energy Storage System (HESS) component sizing, specifically, the lithium-ion (Li-ion) battery and ultracapacitor (UC) for a mild hybrid electric powertrain. In the first stage, optimal sizing of the battery for the powertrain without a UC is solved for a specified drive cycle, which is used in the reported literature. In the second stage, the battery is complemented with a UC cascaded through a direct current-to-direct current (DC/DC) converter in a semi-active configuration. A DP-based formulation is then constructed and solved for the hybrid energy storage subsystem. While the first-stage DP problem has an objective function to minimize the fuel consumption while sustaining the battery charge at the end of the drive cycle, the second-stage DP problem is solved for minimization of the battery capacity loss (i.e., maximization of battery life and better utilization of the battery
Today, magnetic resonance imaging (MRI) technology is widely used by healthcare professionals to examine soft tissues and organs in the body. MRI is an excellent diagnostic tool because it can be used to detect a variety of potentially life-threatening issues ranging from degenerative diseases to tumors in a noninvasive manner. To understand the design challenges involved in developing MRI equipment, specifically when it comes to the selection of radio-frequency (RF) and electrical components such as capacitors, it’s first important to understand the basic physics behind the way MRI machines operate
Supercapacitors are devices that store a dense electrical charge in an electrical field that provides electronics or a power grid with a quick jolt of power on demand. They have a capacitance value far higher than typical capacitors but at the cost of lower voltage limits. Unlike typical capacitors, supercapacitors don’t use conventional solid dielectric (insulator) — they utilize electrostatic double-layer capacitance (typically made of carbon) and electromechanical pseudo-capacitance (metal oxide or conducting polymer). Both contribute to the capacitor’s total capacitance and are designed for many rapid charge/discharge cycles over long-term energy storage. Hybrid supercapacitors boost that capacitance, energy density, and operating voltage (3.8 V maximum) up to 10X over symmetric supercapacitors
Circuit designs exploiting the increased energy storage provided by supercapacitors require more careful consideration of the increased power handling than that of batteries when charging these devices. The unique composition of electrochemical double-layer capacitors (EDLC) inherently allows them to withstand large currents. Table 1 is a brief list of AVX cylindrical (SCC) and series-connected module (SCM) SuperCapacitors, displaying peak current supply and sink current capability. These maximum specifications will typically exceed current capability of charge sources and lead to failures within the power supply system
This paper presents a compact thermal management solution for a high-power traction inverter. The proposed design utilizes a stacked cooling system that enables heat extraction from two of the largest heat sources in a power inverter: the power module and the DC-link capacitor. The base plate of the power module has circular pin fins while the capacitor comes with a flat surface which must be placed on a cold plate to provide the adequate heat dissipation. Incorporating individual cooling mechanisms for the DC-link capacitor and the power module would increase the weight, complexity and overall volume of the inverter housing. The proposed cooling system mitigates these problems by integrating the cooling mechanisms of the power module and the DC-link capacitor within a single cooling system. The cooling mechanism is designed to provide a uniform coolant flow with minimal pressure drop across the heat sink of the power module and DC-link capacitor. The uniform coolant flow also ensures
With recent advances in electric vehicles, there is a plethora of powertrain topologies and components available in the market. Thus, the performance of electric vehicles is highly sensitive to the choice of various powertrain components. This paper presents a multi-objective optimization model that can optimally select component sizes for batteries, supercapacitors, and motors in regular passenger battery-electric vehicles (BEVs). The BEV topology presented here is a hybrid BEV which consists of both a battery pack and a supercapacitor bank. Focus is placed on optimal selection of the battery pack, motor, and supercapacitor combination, from a set of commercially available options, that minimizes the capital cost of the selected power components, the fuel cost over the vehicle lifespan, and the 0-60 mph acceleration time. Available batteries, supercapacitors, and motors are from a market survey. The considered lifespan is taken as 10 years, and the traveling distance is estimated at
We propose low inductance batteries and enhance power density for a inverter. Conventionally, the capacitors are used for smoothing ripple of the inverter. The low inductance battery which responds at carrier frequency of inverter can reduce the capacity of the smoothing capacitors and enable to enhance power density for the inverter. For reducing the inductance, it is necessary to separately understand the impact of electrochemical reaction under wide range of assumed conditions and structural reaction on frequency characteristics. Furthermore, it is also necessary to design the low inductance batteries based on combining the both of characteristics. However, there are no study focusing on modeling by combining such different domains. Therefore, we made original inductance model inside battery considering frequency characteristics among all materials and structural influence with electromagnetic field analysis simulator. Then, we compared obtained simulated values with actual battery
Researchers have created a flexible, lightweight, cost-effective plant-based energy storage device that in the near future could charge devices — even electric cars — within a few minutes
Researchers have engineered a novel type of supercapacitor that remains fully functional even when stretched to eight times its original size. It does not exhibit any wear and tear from being stretched repeatedly and loses only a few percentage points of energy performance after 10,000 cycles of charging and discharging. The supercapacitor could be part of a power-independent, stretchable, flexible electronic system for applications such as wearable electronics or biomedical devices
A new supercapacitor based on manganese oxide could combine the storage capacity of batteries with the high power and fast charging of other supercapacitors. By combining manganese oxide with cobalt manganese oxide, a heterostructure is formed in which interfacial properties can be tuned
As technology advances in the medical device space, electronics design engineers are constantly adapting to meet industry requirements for increased functionality, reduced component size, and absolute reliability. For medical implantables, technological innovations are driven by the ability for electronic components manufacturers to superminiaturize electronic circuits and create advancements in the materials and designs available
Selection of the DC-link capacitance value in an HEV/EV e-Drive power electronic system depends on numerous factors including required voltage/current ratings of the capacitor, power dissipation, thermal limitation, energy storage capacity and impact on system stability. A challenge arises from the capacitance value selection based on DC-link stability due to the influence of multiple hardware parameters, control parameters, operating conditions and cross-coupling effects among them. This paper discusses an impedance-based methodology to determine the minimum required DC-link capacitance value that can enable stable operation of the system in this multi-dimensional variable space. A broad landscape of the minimum capacitance values is also presented to provide insights on the sensitivity of system stability to operating conditions. The target example considered is an HEV e-Drive power electronic system consisting of one bidirectional dc/dc converter and two three-phase electric machine
A new power control unit (PCU) has been developed for a Honda small hybrid vehicle with a two-motor hybrid system launched in 2020. For small hybrid vehicles, downsizing and reducing costs of hybrid systems are major challenges. As such, there were emphatic requirements for the newly developed PCU to be small and affordable. To satisfy these requirements for the PCU, new technologies and components have been introduced such as an all-in-one type intelligent power module (IPM) with integrated functions and reverse conducting IGBT (RC-IGBT), a new control sequence for voltage control unit (VCU), and revised PCU packaging to improve cooling performance. The new IPM has a printed-circuit board (PCB) equipped with an electric control unit (ECU) and gate drive circuits, 7 current sensors, and a power module with RC-IGBTs. This functional integration led to a reduction in the number of main electrical PCU assembly components from 9 in the previous PCU to 2 in the new PCU. In addition, the
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