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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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351 records · Page 20

Operation and Control of Electric Vehicle Charger with Enhanced Dynamic Performance Under Non-Ideal Grid Voltage Condition

This paper presents a three-phase electric vehicle charger connected to the grid, featuring multiple boost converters on the DC side, specifically designed to ensure smooth, oscillation-free power transfer during unsymmetrical voltage sags. Precise control mechanisms are implemented on the boost converter side to regulate both voltage and current on the electric vehicle side, thereby maintaining optimal charging conditions. The control architecture for both the grid-connected and boost converter components is based on the Lyapunov energy function, which is employed to achieve superior dynamic performance and stability. The system's robustness and reliability are demonstrated through its ability to maintain stable operation and efficient power transfer despite fluctuations in grid conditions. Furthermore, the implementation of Lyapunov-based control ensures rapid response and minimal energy loss, enhancing the overall efficiency of the system. To validate the effectiveness of this approach, a comprehensive model of the system was developed and tested using MATLAB/Simulink, with detailed computer simulations conducted across various significant case studies.

DC-DC boost converter↗

Low-Field-Orientation Effect on REBCO Tape Performance and Its Power Cable Application

In this work, low field characteristics, including field orientation dependence relations for four different commercially available REBCO tapes, were investigated in an external field of up to 0.3 T at 77 K. A design method of the performance of a twisted stacked-tape conductor (TSTC) has been developed for a power transmission line. Cable critical current is obtained from an averaged self-field distributed over the cable cross section and the minimum critical current obtained from the field orientation dependence in transverse fields experimentally measured for the single tapes. The performance of three types of TSTCs, i.e., single-, double-, and triple-channel configurations, has been assessed for the four REBCO tapes.

2G tape↗

Rapid and semi-analytical design and simulation of a toroidal magnet made with YBCO and MgB 2 superconductors

Recent advances in second-generation (YBCO) high-temperature superconducting wire could potentially enable the design of super high performance energy storage devices that combine the high energy density of chemical storage with the high power of superconducting magnetic storage. However, the high aspect ratio and the considerable filament size of these wires require the concomitant development of dedicated optimization methods that account for the critical current density in type-II superconductors. In this study, we report on the novel application and results of a CPU-efficient semianalytical computer code based on the Radia 3-D magnetostatics software package. Our algorithm is used to simulate and optimize the energy density of a superconducting magnetic energy storage device model, based on design constraints, such as overall size and number of coils. The rapid performance of the code is pivoted on analytical calculations of the magnetic field based on an efficient implementation of the Biot-Savart law for a large variety of 3-D “base” geometries in the Radia package. The significantly reduced CPU time and simple data input in conjunction with the consideration of realistic input variables, such as material-specific, temperature, and magnetic-field-dependent critical current densities, have enabled the Radia -based algorithm to outperform finite-element approaches in CPU time at the same accuracy levels. Comparative simulations of MgB 2 and YBCO-based devices are performed at 4.2 K, in order to ascertain the realistic efficiency of the design configurations.

2G↗

Present Status and Recent Developments of the Twisted Stacked-Tape Cable Conductor

Here we discuss how the high magnetic field performance of a 40-tape twisted stacked-tape cable (TSTC) conductor made of 4-mm-width 0.1-mm-thick REBCO tapes was successfully tested. The critical current was 6.0 kA, with the n-value of 35, at 4.2 K with a background field of 17 T. No cyclic load effect was observed between 10 and 17 T with the maximum Lorentz load of 102 kN/m. Various issues, such as sample length, nonuniformity of termination resistances, and soldered joint of a coated tape cable, with regard to a TSTC conductor are discussed. Large-scale conductor designs of various scalable TSTC conductors are discussed, taking into account current densities and stabilizers.

2G cable↗

Correlation Between Microstructure and In-Field Performance of Zr-Added REBCO Coated Conductors Made by Advanced MOCVD

In this paper, we present correlation features between critical current density (J c ) and microstructural characteristics of Zr-added (0, 5, and 15 mol.%) REBa 2 Cu 3 O 7-x (REBCO and RE = rare earth) coated conductors fabricated by the novel advanced metal organic chemical vapor deposition technique. The J c along the tape normal (~ B || c-axis) measured by a vibrating sample magnetometer at 30 and 65 K and magnetic flux density range of 0-14 T was used for qualitative comparison of different Zr-added REBCO tapes. It is found that tapes with enhanced in-field J c exhibit a rise of critical current (plateau or fishtail effect) at magnetic flux density 1-8 T and temperatures 65 K. The TEM microstructure analysis indicates that the plateau effect is not the intrinsic property of REBCO matrix but depends on size distribution and density of BaZrO 3 (BZO) self-assembled nanocolumns. Two types of BZO microstructures have been identified: one with uniform BZO diameter 4-7 nm, whereas some films exhibit bottle-shaped BZO nanocolumns with alternating wide and narrow sections, 7-13 and 4-6 nm, respectively. The non-uniform shape and broad size distribution of BZO nanocolumns are correlated to more vortex pinning strength and matching field.

2G high-temperature superconductor (2GHTS)↗

High Temperature Superconducting Quadrupole Magnets With Circular Coils

Particle accelerators used various rather low field mag-nets. In the paper described recently proposed the novel concept of using circular superconducting coils for multipole iron-dominated magnets. This type of magnet design is most suitable for using high temperature superconductors (HTS), and react and wind technol-ogy. The HTS quadrupole magnet with 45 mm aperture, and 100 mm diameter coils was designed, fabricated, and tested. The magnet design includes: the choice of superconductor, 3D magnetic field op-timization, and mechanical design. Furthermore, the magnet models were tested at the liquid nitrogen temperature. The test results are presented and discussed.

2G conductors, coils↗

INL WTB Overview Capabilities Future v14_040419

INL Wireless Test Bed Mission Provide highly-regarded cellular, wireless and communications technical expertise, systems and environment to enable: Test & Demonstrate full scale wireless systems and equipment With and without controlled interference Terrestrial, Subterranean and Airborne Demonstrate new & emerging wireless technologies Develop and Train to Tactics, Techniques and Procedures (TTPs) for wireless systems In a real world environment and configurations at real frequencies and real power levels to make informed decision State-of-the-Art INL WTB Assets and Capabilities Instrumentation: RF waveform analyzers, generators Protocol analyzers Noise generators for controlled interference Established Services & Processes: Spectrum approval & monitoring Safety, Medical, Fire, Security (physical) Resource management - personnel, networks, configuration control Secure, IP protected multi-user facility Broadband data access – entire INL Range Hardware prototyping, scientific labs Visitor – US citizen & foreign national

2G↗

2019 Wireless Test Bed Range Manual

Idaho National Laboratory (INL), Next Generation Wireless Test Bed (NGWTB) program, is part of the Critical Infrastructure Protection (CIP) initiative. Our nation’s reliance on wireless and Internet technology is rapidly evolving as more corporations and government agencies, employees, and handheld devices include mobile connectivity for both voice and data. The competitive advantage offered by a mobile workforce is leading many corporations to make wireless integration and convergence a top business priority. Similarly, military systems worldwide are rapidly embracing next-generation commercial technologies to accelerate network-centric capabilities and provide enhanced situational awareness. While handheld devices such as laptops, BlackBerrys, and cell phones once had limited mobility and range, they are rapidly incorporating new and multiple protocols such as Bluetooth, Wi-Fi, Satellite, and broadband cellular (3G/4G) on a single platform to increase their effectiveness and agility. Worldwide there is exponential growth in public Wi-Fi and/or Satellite connectivity access nodes, and 3G/4G cellular continues to evolve and expand the range and speed of these devices. Additionally, critical infrastructure networks, previously isolated or connected with dedicated wireline circuits, are incorporating Zigbee for wireless sensor networks, wireless LANs for maintenance functions, and cellular or Internet based backhaul to manage control centers. Yet with all the build-up surrounding wireless technology, few understand the complexities surrounding wireless protocols and security, the risks of converged network infrastructures, need for interoperability of communication systems, or mitigation measures to safely use and improve new technologies in both commercial and military environments. With no single vendor source for all the telecommunications equipment needed for wireless infrastructure upgrades, and no one entity providing end-to-end testing or independent validation, the INL's NGWTB program fulfills a niche for facilitating integrated testing of multiple technologies, across multiple wireless domains, of next generation wireless telecommunications systems. NGWTB engineers and technicians have constructed and operate domain infrastructure in the Wireless Personal Area Network (WPAN), Wireless Local Area Network (WLAN), Wireless Metropolitan Area Networks (WMAN), and Wireless Wide Area Networks (WWAN). Advantages that make the INL's NGWTB the place to conduct project and programmatic testing include: • NTIA Experimental Station authority • Geographically isolated and low-noise radio frequency (RF) test areas located on a 890 sm DOE reservation • Access to isolated high-speed LAN and FOT networks The rollout of next-generation networks will involve deploying new technologies at every level including new: handsets, frequencies, antenna arrays, cell configurations that are optimized for both data and voice, massive upgrade of cell controllers’ “land-line” phone links from low bandwidth connections to higher capacity fiber or wireless backhaul, and integration of voice switching and Internet/data network protocols (Voice-Over-IP, Web phones). These systems are expected to greatly transform our nation's communications infrastructure and the types of services it provides.

2G↗