An automated and versatile ultra-low temperature SQUID magnetometer

We present the design and construction of a SQUID-based magnetometer for operation down to temperatures T = 10 mK, while retaining the compatibility with the sample holders typically used in commercial SQUID magnetometers. The system is based on a dc-SQUID coupled to a second-order gradiometer. The sample is placed inside the plastic mixing chamber of a dilution refrigerator and is thermalized directly by the 3He flow. The movement though the pickup coils is obtained by lifting the whole dilution refrigerator insert. A home-developed software provides full automation and an easy user interface.Comment: RevTex, 10 pages, 10 eps figures. High-resolution figures available upon reques

European White Book on Real-Time Power Hardware in the Loop Testing : DERlab Report No. R- 005.0

The European White Book on Real-Time-Powerhardware-in-the-Loop testing is intended to serve as a reference document on the future of testing of electrical power equipment, with specifi c focus on the emerging hardware-in-the-loop activities and application thereof within testing facilities and procedures. It will provide an outlook of how this powerful tool can be utilised to support the development, testing and validation of specifi cally DER equipment. It aims to report on international experience gained thus far and provides case studies on developments and specifi c technical issues, such as the hardware/software interface. This white book compliments the already existing series of DERlab European white books, covering topics such as grid-inverters and grid-connected storag

Development of the Beam Position Monitors for the Diagnostics of the Test Beam Line in the CTF3 at CERN

The work for this thesis is in line with the field of Instrumentation for Particle Accelerators, so called Beam Diagnostics. It is presented the development of a series of electro-mechanical devices called Inductive Pick-Ups (IPU) for Beam Position Monitoring (BPM). A full set of 17 BPM units (16 + 1 spare), named BPS units, were built and installed into the Test Beam Line (TBL), an electron beam decelerator, of the 3rd CLIC Test Facility (CTF3) at CERN ¿European Organization for the Nuclear Research¿. The CTF3, built at CERN by an international collaboration, was meant to demonstrate the technical feasibility of the key concepts for CLIC ¿Compact Linear Collider¿ as a future linear collider based on the novel two-beam acceleration scheme, and in order to achieve the next energy frontier for a lepton collider in theMulti-TeV scale. Modern particle accelerators and in particular future colliders like CLIC requires an extreme alignment and stabilization of the beam in order to enhance its quality, which rely heavily on a beam based alignment techniques. Here the BPMs, like the BPS-IPU, play an important role providing the beam position with precision and high resolution, besides a beam current measurement in the case of the BPS, along the beam lines. The BPS project carried out at IFIC was mainly developed in two phases: prototyping and series production and test for the TBL. In the first project phase two fully functional BPS prototypes were constructed, focusing in this thesis work on the electronic design of the BPS on-board PCBs (Printed Circuit Boards) which are based on transformers for the current sensing and beam position measurement. Furthermore, it is described the monitor mechanical design with emphasis on all the parts directly involved in its electromagnetic functioning, as a result of the coupling of the EM fields generated by the beam with those parts. For that, it was studied its operational parameters, according the TBL specifications, and it was also simulated a new circuital model reproducing the BPS monitor frequency response for its operational bandwidth (1kHz-100MHz). These prototypes were initially tested in the laboratories of the BI-PI section¿Beam Instrumentation - Position and Intensity¿ at CERN. In the second project phase the BPS monitor series, which were built based on the experience acquired during the prototyping phase, the work was focused on the realization of the characterization tests to measure the main operational parameters of each series monitor, for which it was designed and constructed two test benches with different purposes and frequency regions. The first one is designed to work in the low frequency region, between 1kHz-100MHz, in the time scale of the electron beam pulse with a repetition period of 1s and an approximate duration of 140ns. This kind of test setups called Wire Test-bench are commonly used in the accelerators instrumentation field in order to determine the characteristic parameters of a BPM (or pick-up) like its linearity and precision in the position measurement, and also its frequency response (bandwidth). This is done by emulating a low current intensity beam with a stretched wire carrying a current signals which can be precisely positioned with respect the device under test. This test bench was specifically made for the BPS monitor and conceived to perform the measurement data acquisition in an automated way, managing the measurement equipment and the wire positioning motors controller from a PC workstation. Each one of the BPS monitors series were characterized by using this system at the IFIC labs, and the test results and analysis are presented in this work. On the other hand, the high frequency tests, above the X band in the microwave spectrum and at the time scale of the micro-bunch pulses with a bunching period of 83ps (12GHz) inside a long 140ns pulse, were performed in order to measure the longitudinal impedance of the BPS monitor. This must be low enough in order to minimize the perturbations on the beam produced at crossing the monitor, which affects to its stability during the propagation along the line. For that, it was built the high frequency test bench as a coaxial waveguide structure of 24mm diameter matched at 50¿ and with a bandwidth from 18MHz to 30GHz, which was previously simulated, and having room in the middle to place the BPS as the device under test. This high frequency test bench is able to reproduce the TEM (Transversal Electro-Magnetic) propagative modes corresponding to an ultra-relativistic electron beam of 12GHz bunching frequency, so that the Scattering parameters can be measured to obtain the longitudinal impedance of the BPS in the frequency range of interest. Finally, it is also presented the results of the beam test made in the TBL line, with beam currents from 3.5A to 13A (max. available at the moment of the test). In order to determine the minimum resolution attainable by a BPS monitor in the measurement of the beam position, being the device figure of merit, with a resolution goal of 5¿m at maximum beam current of 28A according to the TBL specifications.García Garrigós, JJ. (2013). Development of the Beam Position Monitors for the Diagnostics of the Test Beam Line in the CTF3 at CERN [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/34327TESI

Methods for Determining Blood Flow Through Intact Vessels of Experimental Animals Under Conditions of Gravitational Stress and in Extra-terrestrial Space Capsules Final Report, 1 Nov. 1960 - 31 Dec. 1964

Electromagnetic blood flow meter to determine blood flow through intact vessels of test animals in gravitational stress and in extraterrestrial space capsule

Distribution Line Multi-tool

Power companies are always interested in the best possible monitoring equipment for their grid. The power line multi-tool developed would aid in the monitoring of the power system’s distribution network. This device assesses the current conditions of distribution power lines. The device is able to measure current, detect downed power lines, as well as recognize fire starting conditions, and have wireless communication for ease of access and installation. Overall this device greatly aids in helping utilities monitor their grid in more detail. With the increase of dry climates yearly, several utility companies are taking measures to aid in the prevention of power line based fires. The use of the distribution line multi-tool gives power companies an additional resource in fire prevention. With accurate data received, power companies can take the necessary precautions to prevent power line based fires. One of the deadliest and most destructive fires of recent history in Paradise California has put power companies on high alert and motivated the state to provide funding to utilities to harden their infrastructure and a product like this fits perfectly into this agenda of fire mitigation. With hundreds of thousands of distribution lines throughout California’s vast terrain, monitoring them has become a cumbersome task yet more necessary in recent years. With a drier than usual climate, the environment has become more prone to fire, especially with areas with distribution lines running through them. With high distribution voltages used and the occurrence of large short circuits on these systems, downed power lines can create fire hazards. A number of factors can cause downed power lines, which includes galloping from winds, impact based falls, and excessive tension on distribution cables or poles. When these poles fall, they have the potential to not only cause a short circuit, which can damage nearby equipment or turn off the power for customers but also cause fires. These high voltages and extreme transient currents mixed in a dry, wilted environment increases the opportunity for a fire to be started but for it to also spread with ease

Power system applications of fiber optics

Power system applications of optical systems, primarily using fiber optics, are reviewed. The first section reviews fibers as components of communication systems. The second section deals with fiber sensors for power systems, reviewing the many ways light sources and fibers can be combined to make measurements. Methods of measuring electric field gradient are discussed. Optical data processing is the subject of the third section, which begins by reviewing some widely different examples and concludes by outlining some potential applications in power systems: fault location in transformers, optical switching for light fired thyristors and fault detection based on the inherent symmetry of most power apparatus. The fourth and final section is concerned with using optical fibers to transmit power to electric equipment in a high voltage situation, potentially replacing expensive high voltage low power transformers. JPL has designed small photodiodes specifically for this purpose, and fabricated and tested several samples. This work is described

Connection of renewable energy sources to the power grid

Diplomová práce se zabývá obnovitelnými zdroji energie a druhy, které se nejvíce využívají. Teoretická část je věnována obecným informacím o obnovitelných zdrojích energie, typech elektráren a v další části se zaměřuje na fotovoltaické elektrárny. Praktická část ilustruje připojení fotovoltaické elektrárny do sítě vysokého napětí (22kV) ve Středočeském kraji. Dále jsou v práci uvedena pravidla pro připojení rozptýlených výroben elektřiny z obnovitelných zdrojů energie do distribuční sítě, napěťový profil podél vedení před a po připojení FVE do distribuční sítě.This thesis deals with the renewable energy and its main types. The theoretical part is about the general information on renewable energy sources, types of power plants, focusing on photovoltaic power plants. The practical part illustrates the connection of photovoltaic power plant to a medium voltage network (22kV) in Central Bohemia region. The following part is devoted to the rules for connecting dispersed energy sources to the distribution network, voltage profile along the lines before and after connecting the PVPP's into the distribution network

Modelling the Interoperability and the Use of Control Equipment in Electrical Substations

Simulators can be defined as information systems which reliably reproduce specific phenomena and they are mainly used in training, although their field of application has grown to include manufacturing and medicine among others. In electrical engineering, simulation is an indispensable tool when working with complex systems due to the fact that it enables engineers to understand how systems work without actually needing to see them. They can learn how they work in different circumstances and optimize their design with considerably less cost in terms of time and money than if they had to carry out tests on a physical system. By using computer simulation, not only can an electrical system be designed, but it can also be optimized and its behavior examined in-depth more quickly and cheaply than by using prototypes, tests or analytical studies. Therefore, by being able to see the responses produced as the different parameters are varied, a much deeper understanding of the system under study is reached. In order to properly simulate a virtual world, technologies such as realistic graphics and dynamic simulation with real-time calculations must be used. Peripherals must be used for the system to interact with the user and the immersion comes as a result of stimuli to sight, hearing and touch. A critical factor is the possibility to solve the equations in real-time; that is, there should be no delay compared to the normal environment’s response. There is an important amount of effort being directed towards these objectives. This paragraphs deals with the development of an operation simulator for training and the fundamental objective is to develop a simulator for electrical substations. It will present the methodology to model, simulate and optimize the interoperability and the use of control equipment in electrical an substation to train operators by means of a virtual reality environment