Advanced flywheel technology for space applications

Flywheel energy storage systems (FESSs) improve the quality of the electric power delivered by wind generators, and help these generators contributing to the ancillary services. Presently, FESSs containing a flux-oriented controlled induction machine (IM) are mainly considered for this kind of application. The paper proposes the direct torque control (DTC) for an IM-based FESS associated to a variable-speed wind generator, and proves through simulation and experimental results that it could be a better alternative. This DTC application entails two specific aspects: 1) the IM must operate in the flux-weakening region, and 2) it must shift quickly and repeatedly between motoring and generating operation modes. DTC improvement for increasing the FESS efficiency, when it operates at small power values, is discussed. Some aspects concerning the flywheel design and the choice of the filter used in the FESS supervisor are also addressed. Index Terms-DC-linkvoltage regulation, direct torque control (DTC), flywheel energy storage, flux-oriented controlled (FOC), induction machine (IM), power flow supervision, variable-speed wind generator (VSWG).

show abstract

“…9), and the rotor-flux position results from the rotor speed ω m and slip frequency ω sl θ r = (ω m + ω sl ) dt (16) and…”

Section: B Foc Principlementioning

confidence: 99%

Design and Control Strategies of an Induction-Machine-Based Flywheel Energy Storage System Associated to a Variable-Speed Wind Generator

Cimuca

Breban

Radulescu

et al. 2010

IEEE Trans. Energy Convers.

129

View full text Add to dashboard Cite

show abstract

“…where _ R R is the reaction rate, N is the atomic density, is the neutron flux, and is a proportionality constant that will vary for different interactions and neutron energies and will be unique for targets of different isotopes. N is typically expressed in atoms per cm 3 , is expressed as neutrons per cm 2 per second, and the proportionality constant, , is expressed in cm 2 . is commonly referred to as the microscopic interaction cross section and can also be expressed in units of barns (b), where 1 b ¼ 10 À24 cm 2 .…”

Section: Cold Neutron Prompt Gamma Activation Analysismentioning

confidence: 99%

“…Achieving maximum energy density typically depends on achieving predictable high strength in the manufactured components. While rapid prototyping approaches have been developed to permit the design of components with predictable mechanical properties [2], manufacturing defects can compromise these properties. Consequently, non-destructive evaluation is required to certify fabricated components for each application.…”

Section: Introductionmentioning

confidence: 99%

Non-Destructive Evaluation of Carbon Fiber Composite Reinforcement Content

Dorsey

Hebner

Charlton

2004

Journal of Composite Materials

View full text Add to dashboard Cite

The use of light-weight, high-strength composite materials in motors, generators, and energy storage devices has become common as a means to maximize energy density. To ensure reliability, non-destructive and destructive evaluation techniques have been employed to measure the mechanical properties of fabricated components. In carbon fiber-reinforced, polymer matrix composites, mechanical strength is primarily derived from the fiber volume fraction. Due to the lack of a nondestructive method, common techniques for fiber volume determination are currently destructive. In this investigation, a non-destructive method for the measurement of the fiber volume fraction of carbon fiber-reinforced, polymer matrix composites has been developed using cold neutron prompt gamma activation analysis (PGAA). Fiber volume determination is accomplished in this technique by measuring and comparing the carbon and hydrogen content in a given sample (or samples). PGAA is a nuclear analytical technique performed by exposing a sample to neutron radiation. PGAA measurements are non-destructive and can be performed without chemical preparation of the sample. Fiber volumes of several composite coupons have been determined relative to standard samples of known fiber volume and measurements are in good agreement with values predicted by acid digestion tests. Fiber volume measurement using PGAA can potentially be applied to any composite material where the contents of the matrix and reinforcement differ. The technique can also be spatially sensitive, with resolution limited by the dimensions of the neutron beam that is used.

show abstract

“…As for power system applications, the FES can be used for power regulation between utilities in the power grid [12][13][14][15][16]. For space applications, the FES can supply energy storage with the smallest mass and also can be used for attitude control for guidance of the craft [17][18][19]. For UPS applications, the FES system can serve as an UPS to supply energy for vital loads, such as hospitals, central computer rooms, government agencies, etc.…”

Section: Introductionmentioning

confidence: 99%

Research on the Torque and Back EMF Performance of a High Speed PMSM Used for Flywheel Energy Storage

Zhao

et al. 2015

Energies

View full text Add to dashboard Cite

Abstract:Due to advantages such as high energy density, high power density, rapid charge and discharge, high cyclic-life, and environmentally friendly, flywheel energy storage systems (FESs) are widely used in various fields. However, the performance of FES systems depends on the performance of a high speed machine, therefore, the design and optimization of a high efficiency and high power density machine are very crucial to improve the performance of the whole FES system. In this paper, a high speed permanent-magnet synchronous machine (PMSM) is researched. Considering the requirement of low torque ripple in low speed and loss caused by back electromotive force (EMF) harmonics, the electromagnetic performance is improved from points of view of slot/pole matching, magnetic-pole embrace with the finite element method (FEM). Furthermore, the magnetic-pole eccentricity, the slot opening, the thickness of PM and air-gap length are also optimized with Taguchi method. The electromagnetic performance, such as torque ripple, cogging torque, average torque and back EMF wave are much improved after optimization. Finally, experiments are carried out to verify the calculated results.

show abstract

Advanced flywheel technology for space applications

Cited by 5 publications

References 2 publications

Design and Control Strategies of an Induction-Machine-Based Flywheel Energy Storage System Associated to a Variable-Speed Wind Generator

Design and Control Strategies of an Induction-Machine-Based Flywheel Energy Storage System Associated to a Variable-Speed Wind Generator

Non-Destructive Evaluation of Carbon Fiber Composite Reinforcement Content

Research on the Torque and Back EMF Performance of a High Speed PMSM Used for Flywheel Energy Storage

Contact Info

Product

Resources

About