White Papers

As a leading authority on ultracapacitor technology, Maxwell Technologies offers a full library of whitepapers, authored or developed by our industry experts.

Voltage Sag

Utility power in the U.S. is very reliable; we count on it to be there, expect it to be there, and it usually is. Barring natural disasters and the rare systemwide blackout, the U.S. has a continuous supply of electrical power. But what is the quality of that power? Voltage sags are the most common power disturbance experienced by factory equipment. Read how ultracapacitors are used as a storage solution for hardening sensitive equipment against voltage sag and ensuring productivity.
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Bridge Power

Bridge power describes the short-term power necessary to “bridge” from one long-term power source to another. Bridge power is needed because typical standby power generation equipment is not instantly available, and takes time to be brought online. The combination of both bridge and long term power generation is necessary because the cost associated with extending bridge power beyond a few minutes is high, and maintenance and reliability issues where batteries are employed may make a single “long-term bridge” prohibitive. Learn more about how ultracapacitors are used in bridge power applications.
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Ultracapacitor Power for a Drag Racecar

A student team from Brigham Young University (BYU) set a new record for the world's fastest electric drag racecar. The team modified a production EV1 donated to the university by the General Motors Corporation and installed a bank of 160 Maxwell Technologies BOOSTCAP® Ultracapacitors rated at 2700 farads each. This paper describes the design of the capacitor pack, the car’s drive train, the charging method and other modifications of the vehicle. Also discussed are the performance and race data from an official quarter-mile drag race sanctioned by the National Electric Drag Racing Association as well as a simulation model for vehicle performance was also developed and is presented here.
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Ultracapacitors Improve Reliability for Wind Turbine Pitch Systems

Today's advanced wind turbines use pitch control systems to adjust the blade angles for optimal performance. Traditionally, these systems have been powered by batteries but the long life, reliability and maintenance-free characteristics of BOOSTCAP® ultracapacitors make them a better solution for this application.
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A Purely Ultracapacitor Energy Storage System for Hybrid Electric Vehicles Utilizing a Microcontroller- Based dc-dc Boost Converter

The design and testing of a purely ultracapacitor energy storage system for the improvement of hybrid electric vehicles is presented. The system utilizes two large ultracapacitor banks for energy storage and a dc-dc boost converter that is capable of supplying 8kW for voltage regulation. The system provides greater roundtrip efficiency over batteries, improves a vehicle’s ability to recapture energy from regenerative braking, and is controlled and protected by a microcontroller. The paper presents design considerations, simulation, and hardware results of the system.
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A Supercapacitor-Based Energy-Storage Substation for Voltage-Compensation in Weak Transportation

A supercapacitive-storage based substation for the compensation of resistive voltage-drops in transportation networks is proposed. It allows to feed as a current-source in any voltage conditions of the line. The system has been designed as a compensation-substation to be placed at weak points like end-of-line stations, instead of additional feeding substations. A dedicated power-electronic converter with an associated control system for the stabilization of the voltage level at the point of coupling in case of strong perturbations is proposed. Practical results are also presented, which have been recorded from a reduced-size prototype.
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Susceptibility of “Ultracapacitors” to Proton and Gamma Irradiation

Ultracapacitors are promising components for energy storage, power backup and delivery systems. This study examines the possible effects associated with gamma and proton irradiation in selected samples up to 1200 Farad.
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Ultracapacitors as Energy Buffers in a Multiple Zone Electrical Distribution System

A multiple zone electrical distribution system architecture augmented with local energy buffers is one method of addressing the need for redundancy that safety critical and security systems require. New introductions of x-by-wire functionality, idle-stop power trains, and electrified engine functions such as electro-mechanical engine valve actuation also benefit from modular and distributed local energy buffering offered by ultracapacitors. Ultracapacitors are non-Faradic surface effect storage devices that offer pulse power and power cycling capability far in excess of Faradic, bulk storage, electrochemical cells. Power management for safety critical systems such as steer, brake and drive by wire benefit from distributed energy modules that are positioned locally, are lower in mass, and are more energetic than batteries. Ultracapacitors have already found application in the propulsion system of conventional gasoline and diesel hybrid as well as fuel cell hybrid vehicles. The reason for the acceptance of ultracapacitors in vehicle propulsion systems is their high pulse power capability, fast transient response, and high efficiency during discharge and re-charging plus full charge cycling in excess of 100k cycles. The ultracapacitor is now proven to be an able augmentation to hybrid power trains as an electrical peaking unit. In this paper the application of ultracapacitors as distributed energy storage buffers in the vehicles electrical system is investigated.
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Ultracapacitor Assisted Electric Drives for Transportation

Non-Faradic surface effect storage devices such as ultracapacitors offer pulse power and power cycling capability far in excess of Faradic, bulk storage, electrochemical cells for vehicular use. Vehicle applications for electric drives have been delayed due to technical inadequacy in these fiercely cost sensitive systems. Particularly in safety critical systems such as steer, brake and drive by wire where the cost of redundant systems would be prohibitive. Similarly for the vehicle power train where the demands for idle-stop and electrification of key functions such as engine cranking, electromechanical valve actuation and hybridization are concerned. In this paper both safety critical and power train systems are re-assessed within the context of distributed energy storage modules in the vehicle electrical distribution system to satisfy the requirements for power supply redundancy.
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Ultracapacitor Applications in the Power Electronic World

There has been a lot of progress in control and motor design, due to the increasing power demand in electric applications, as well as ongoing pressures for more environmentally friendly and high efficiency solutions. However, designers and engineers have not been successful with regard to the electric power storage systems. This is due primarily to the fact that batteries are used to provide the power peaks in most of the currently developed solutions relying on a power storage system. The deficiencies of battery storage systems are many and they create a variety of design challenges for engineers. Batteries have a poor low-temperature performance, a very limited lifetime under extreme conditions - resulting in repeated replacement throughout the life of the system - and they are not designed to satisfy the most important requirements of power sources: To provide bursts of power in the seconds range over many hundreds of thousands of cycles.
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Evaluation of Maxwell Technologies PC5 Ultracapacitor

The Parts Analysis and Assurance (PA&A) group at the Johnson Space Center (JSC) evaluated the PC5 Ultracapacitor from Maxwell Technologies and this evaluation reports on the results of the tests done. The PC5 is used in the International Space Station PEEK (Portable Electrical Equipment Kit). The PEEK hardware provides electrical power extension cables and outlets as well as 120 to 28Vdc converter units to power portable electrical hardware on the ISS.
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Ultracapacitors, the New Thinking in the Automotive World

Due to the increasing power demand in future vehicles for comfort improvement, as well as ongoing pressures for more environmentally friendly means of transportation, automotive manufacturers are developing alternatives to existing fossil fuel-driven vehicles. Perhaps the most promising near-term alternative to fuel-cell vehicles, which will not be ready for volume production for at least a decade, is hybrid electric vehicle (HEV) technology. While progress has been made in control, engine and motor design, there has not been much success with regard to the electric power storage systems. This is due primarily to the fact that batteries are used to provide the power peaks in most of the currently developed hybrid electric vehicles. But the deficiencies of battery storage systems are multiple and they create many design challenges for automotive engineers.
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Power Modules Enable Electric Drive Systems

Automotive technology is on the brink of a three-pronged revolution; the transition from heat engine propulsion to electric drive; 12 volts to 42 volts; and distributed electrical power. This free white paper explores how drivetrain and distributed power concepts will satisfy the two converging demands of environment and consumer which are driving this revolution.
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Top 10 Reasons for Using Ultracapacitors in Your System Design

Discover 10 ways that Maxwell's ultracapacitors give system designers more freedom by allowing hybrid power system solutions that cost less and perform better than non-hybrid solutions.
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Ultracapacitors and the Hybrid Electric Vehicle

Read about current Hybrid Electric Vehicle power solutions to learn how Maxwell's ultracapacitors can be used to improve vehicle performance and safety, while reducing costs, in this exciting new industry sector.
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Ultracapacitor System Design: Optimizing Hybrid Electric Vehicles with Fuel Cell Power

The automotive industry's recent push towards developing electric and hybrid electric vehicles (EV and HEVs) is a direct response to the growing global pressure to improve the environment and has resulted in a search for significantly cleaner and more efficient vehicles.
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