Two-wire System Research Articles

Equivalent Measurement Method for High-Field-Intensity Radiation Sensitivity of Two-Wire Interconnection System

Equivalent Measurement Method for High-Field-Intensity Radiation Sensitivity of Two-Wire Interconnection System

Transradial/brachial carotid artery stenting with proximal protection: technical instructions, acute results and long-term outcomes

The aim of this study was to evaluate the feasibility, safety and efficacy of transradial/brachial (TR/TB) carotid artery stenting (CAS) with proximal cerebral protection (PCP) as a first line of treatment of carotid artery stenosis. Among 556 patients with significant (>50% if symptomatic or >70% if asymptomatic by Doppler US) unilateral, lipid-rich carotid artery stenosis undergoing TR/TB CAS, 137 (24.5%) deemed at high-risk for periprocedural cerebral embolization were scheduled for PCP with Mo.MA Ultra or Mo.MA mono-balloon. In patients with very complex anatomy the standard technique was modified loading the Mo.MA catheter without mandrel on two-wire system (so called 'No MAndrel 2 wire' technique, No.MA2) to increase support and deliverability. Device, technical and procedural successes both acute and at follow-up were the main outcomes. Mean patients' age was 74±7 years (93% male), 15% were symptomatic and 59.6% owned 'high-surgical-risk' features. Stenosis degree was 85±7% with soft composition in all (by CT-angiography). TR and TB approach were selected in 92 (67%) and 45 (33%) patients, respectively. Target carotid axes were right, left bovine and left non bovine in 55%, 38% and 7% of patients. Procedures were successfully completed in all patients (intention-to-treat basis) with the standard Mo.MA Ultra system in 129 patients and the Mo.MA mono-balloon in 8 patients. No.MA2 technique was succesfully used in 16 patients as 'bailout' and in 27 patients as 'first line'). Device and technical success was 97% (133/137 patients) due to crossover to femoral access in 3 cases, and Mo.MA too short to engage the ECA in 1 patient. The procedural success was 96.7% (131/137, two minor strokes). Procedural time and fluoroscopy time were increased with No.MA2 technique. One major vascular complication occurred, in the TB group, while chronic radial occlusion was detected by Doppler ultrasound in 7/92 patients (7.1%) at 372±163 days of follow-up. The event-free survival was 91% and the stroke rate was 0%. TR/TB CAS with proximal protection is a feasible, safe and effective strategy and may be considered a first line strategy in all comer patients.

Continuous-Control-Set Model Predictive Control for Three-Level DC–DC Converter with Unbalanced Loads in Bipolar Electric Vehicle Charging Stations

Zero-emission transportation is currently a public priority, especially in big cities. For this reason, the use of electric vehicles (EVs) is receiving much attention. To facilitate the adoption of EVs, a proper charging infrastructure together with energy management is essential. This article proposes a design guideline for a direct current (DC) charging station with bipolar properties. A bipolar system can convert a two-wire system into three wires in a microgrid system with a neutral line. The configuration of the bipolar system supports different loads; therefore, the unbalanced operation is inherent to the system. The proposed bipolar DC charging station (CS) has a three-level balancing converter that reduces the step-down effort chargers. Moreover, this paper proposes the continuous-control-set model predictive control (CCS-MPC)-based balancing strategy that allows the handling of different output loads while keeping the neutral-line voltage efficiently regulated with improved dynamic performance compared to a traditional controller. Stability and parameter robustness analyses are also performed for the control parameter selection. To ensure the performance of the proposed method, both simulation and experimental results are presented and compared with those obtained from the traditional methods.

ANALISA JARINGAN DISTRIBUSI TEGANGAN MENENGAH DENGAN SISTEM SINGLE WIRE EARTH RETURN UNTUK WILAYAH TERTINGGAL, TERDEPAN DAN TERLUAR

Indonesia's rural electrification rate (RER) is still low. This is due to the high cost of installing a conventional three-phase or single-phase power supply in distributed rural loads. However, the Rural Energy Agency and the National Utility have made many efforts to address this issue. To this end, this document proposes a Single Wire Earth Return (SWER) electrification scheme for the electrification of a selected village, namely Serang, Banten. Field data were collected and used to design a potential SWER distribution network. A mathematical model representing SWER for Serang, Banten was developed and simulations were performed to determine soil potential and soil resistance. These two are important every time you install a HEAVY line. In addition, a technical and economic comparison was made in order to determine the short-term costs of the proposed SWER with the existing single-phase two-wire (SPTW) system. The technical and economic analysis shows that the proposed SWER system will achieve a cost saving of 50% compared to the installation of the SPTW system for Serang Banten electrification.

Вибір системи живлення низьковольтних однофазних електроприймачів повітряних ліній напругою 220/380 В

Two-phase three-wire and single-phase two-wire branches from main three-phase lines are integral components of three-phase four-wire systems. Therefore, the aim of this work is to choose the optimal power supply system for single-phase electrical receivers depending on their power and branch length. The comparison of single-, two- and three-phase power supply systems of single-phase electric receivers is carried out and analytical expressions are obtained to determine power losses, phase voltage loss and wire cross section for allowable voltage loss at the same total active load power and its equal distribution between phases. Based on the obtained expressions, the total power losses, voltage loss in phase and neutral wires for different power supply systems are analyzed. In the transition from a three-phase four-wire power supply system of single-phase electric receivers to a single-phase two-wire or two-phase three-wire system with the same total load power and equal load phases with wire cross sections selected for allowable voltage loss, power loss and phase voltage with a corresponding decrease in their active resistance. It is shown that in some cases the use of single-phase and two-phase branches saves conductive materials in comparison with the three-phase linear branch, the cross section of which is inflated due to the need to ensure the condition of mechanical strength. The dependences of the limiting length of three-phase and single-phase overhead insulated lines, which corresponds to the allowable voltage loss, on the active load power are calculated. It is shown that the limiting length of three-phase linear branches significantly exceeds the limiting lengths of single-phase and two-phase branches at the same load power. The optimal version of the power supply system should be selected on the basis of technical and economic calculation depending on the load capacity, line length and allowable voltage loss.

Adaptive Linear Neural Network Approach for Three-Phase Four-Wire Active Power Filtering under Non-Ideal Grid and Unbalanced Load Scenarios

This paper presents the enhancements performed on the adaptive linear neuron (ADALINE) technique so that it can be applied for active power filtering purposes in a three-phase four-wire system. In the context of active power filtering, the ADALINE technique which was initially developed for a single-phase two-wire system has been further expanded to suit three-phase three-wire system. For both systems, ADALINE techniques have been reported to be effective even when the grid voltage is distorted and/or unbalanced. However, further works that study the possibility to apply ADALINE technique in a three-phase four-wire system which invariably carries unbalanced loads, are rather limited. Hence, in this work, a control algorithm (named as enhanced-ADALINE) which combines the strength of highly selective filter (HSF), ADALINE concept and averaging function is proposed, to manage harmonics mitigation by shunt active power filter (SAPF) under non-ideal grid and unbalanced load scenarios. MATLAB-Simulink software is utilized to conduct an exhaustive simulation study which includes circuit connection of SAPF in a three-phase four-wire system, design of control algorithms, and performance assessments. Benchmarking with the existing algorithm is performed to examine the benefits of using the proposed algorithm. From the analysis, simulation findings are presented and thoroughly discussed to verify design concept, capability, and relevance of the proposed algorithm.

A Layered Pork Model for Subdermal Antenna Tests at 433 MHz

Clinical or Biological Impact: Antennas for next generation implantable medical devices are likely to be distributed throughout the body, particularly in the near-surface subdermal regions, rather than tethered to the surface of the implantable device. A simple test bed for evaluating subdermal antennas during the design phase is needed. Objectives: The objectives of this paper are to create a simple biological test bed for subdermal implantable antennas that includes the normal expected variation of the tissues. Technology or Method: A layered model using pork products with skin, pork fat or lard, and pork loin or ground pork is used. Results: The ex vivo porcine tissues are similar to in vivo human tissues. Pork fat and loin have more variability than lard and ground pork but are more difficult in which to imbed subdermal antennas. This model provides an easy to use platform for testing subdermal antennas in the lab. This test bed was developed for 433 MHz: the industrial–scientific–medical band closest to the MedRadio band (402–405 MHz). Initial tests are demonstrated on a two-wire passive system for focusing power within the muscle region.

Numerical study of boiling around wires and influence of active or passive neighbours on vapour film dynamics

In the present study pool boiling around a heated wire has been simulated at atmospheric pressure, considering the wire to be at the constant temperature heat source. Film dynamics, bubble nucleation, growth, merging and pinch off has been observed in with perfectly smooth and uniform horizontal wire without any nucleation site. Effect of increase of the degree of superheat on boiling rate, measured in terms of vapour generation and bubble population has been studied next. Similar studies have been done by inclining the wire at different angles (10°, 45°, 60° and vertical), where axial and azimuthal bubble sliding and more efficient bubble merging have been observed. Bubble size and population distribution have been investigated along the length of the inclined wire to link up with corresponding enhancement in boiling rate. For understanding the effect of active and passive neighbour, horizontal boiling around two-wire system has been studied. First horizontal wires have been stacked at the same vertical plane and different active and passive combination have been simulated. Also boiling from two active wires placed at same horizontal plane has been studied for different wire spacings. For all these cases bubble life cycle has been investigated to understand the role of neighbouring wire. Effect of these neighbouring wires on boiling heat transfer and vapour generation rate has been reported.

Thermalization dynamics of two correlated bosonic quantum wires after a split

Coherently splitting a one-dimensional Bose gas provides an attractive, experimentally estab- lished platform to investigate many-body quantum dynamics. At short enough times, the dynamics is dominated by the dephasing of single quasi-particles, and well described by the relaxation to- wards a generalized Gibbs ensemble corresponding to the free Luttinger theory. At later times on the other hand, the approach to a thermal Gibbs ensemble is expected for a generic, interacting quantum system. Here, we go one step beyond the quadratic Luttinger theory and include the lead- ing phonon-phonon interactions. By applying kinetic theory and non-equilibrium Dyson-Schwinger equations, we analyze the full relaxation dynamics beyond dephasing and determine the asymptotic thermalization process in the two-wire system for a symmetric splitting protocol. The major ob- servables are the different phonon occupation functions and the experimentally accessible coherence factor, as well as the phase correlations between the two wires. We demonstrate that, depending on the splitting protocol, the presence of phonon collisions can have significant influence on the asymptotic evolution of these observables, which makes the corresponding thermalization dynamics experimentally accessible.

Двухпроводная система электропередачи трёхфазного тока

The considered two-wire three-phase current power transmission system contains two phase number transformer converters (PNTC). The first converter (PNTC-1) converts the symmetrical system of three-phase currents of the power supply source into a single-phase current with concurrently increasing the voltage of the two-wire line via which the electric power is transmitted over a significant distance to the second converter (PNTC-2). The second converter reduces the voltage and converts the single-phase current into a symmetrical system of three-phase currents. Currents are converted in each transformer converter by means of a three-phase transformer having a special winding connection diagram and two capacitor banks (phase converting elements). The article presents the PNTC-1 analysis results based on which mathematical expressions have been obtained for the impedances of the phase converting elements and for the voltage, current and power capacity of these elements, transformer, and load. The phasor diagram for the PNTC-1 has been drawn along with graphic dependences of the converter currents and reactive power values of the phase converting elements as a function of load cosjL,and the dependences of capacitor bank capacitances on the load current. Mathematical expressions for all parameters of the PNTC-2 are given.

Designing an Optimal Lightning Protection Scheme for Substations Using Shielding Wires

An optimal lightning protection scheme for a substation using shielding wires is investigated in this paper through computer software analysis. An economic approach is utilized by choosing a reasonable trade-off between protection, the number of shielding wires and the heights of them from the ground. This study is initially applied to a simple two-wire system and then extended to a sample substation. The solution for each problem is executed in MATLAB and 3-D realization is shown.

無瞬断給電や他電源との並列運転に適した単相三線系統向け仮想同期発電機制御

In Japan, commercial grid for ordinary residential houses consists of a single-phase three-wire system. In general, unbalanced load power is supplied by the commercial grid. Recently, there have been an increasing number of houses equipped with the emergency power units in preparation for possible power outages. However, because most of the conventional power inverters in these units cannot supply unbalanced power, home appliances must be reconnected to dedicated outlets when they are used in the grid-disconnected operation. To solve such an inconvenient situation, we propose a method that enables the uninterruptible power supply between the grid-connected and grid-disconnected operations for single-phase three-wire systems. This control method is mounted on the power inverters and is called the virtual synchronous generator (VSG) control. The method is developed expanding the previous method for a single-phase two-wire system.

The Influence of Series and Parallel Current Flowing Through Two Paralleled Co-based Amorphous Wires on Giant Magneto Impedance Effect

Background: Giant Magneto Impedance (GMI) is effectively enhanced by the mutual magnetic interaction between two wires arranged in parallel setup. The direction of current flowing through two wires (series or parallel current mode) has a key role in this change. Methods: The aim of this research is to study the GMI properties of series and parallel current flowing through two amorphous Co-based wires in parallel setup and compare it to a single wire. Therefore, the wires with stoichiometric formula Co 68.15 Fe 4.35 Si 12.5 B 15 were prepared by in-rotating water spinning method with diameter about 125 μm. Findings: The best GMI response measured in series current mode and 8 mm distance between two wires. The GMI ratio increases from 300% of single wire to 480% of two wires in series current mode. However when the current flowing through two wires is in parallel mode, the GMI ratio decreases to 180% which is due to reduction of effective magnetic field. For two-wire system in series current mode, the magnetic interaction is stronger than parallel current configuration. Application: These results demonstrate that the GMI response could be effectively improved in two-wire series current system, which is useful for the application of low dimension and high sensitive GMI sensors.

Interaction effects on proximity-induced superconductivity in semiconducting nanowires

We investigate the effect of electron-electron interactions on proximity-induced $s$-wave superconductivity in one-dimensional nanowires. We treat the interactions on a self-consistent mean-field level, and find an analytic expression for the effective pairing potential in the presence of interactions, valid for a weakly tunnel coupled wire. We show that for a set of two nanowires placed in parallel on a superconducting substrate, the interaction-induced reduction of the pairing energy could result in the effective interwire pairing potential exceeding the intrawire potential, which is one of the requirements for creating a time-reversal symmetric topological superconducting state in such a two-wire system.

Two-Wire Distribution System for Power Supply to Three-Phase Rural Facilities

Nowadays, the electric power supply to rural facilities is commonly composed by single-phase medium voltage grids. Eventually, some of these rural facilities require the use of more significant driving loads, making necessary the replacing of the single-phase networks by a new medium voltage three-phase network. Thus, despite the fact it is a new or an existing facility, the construction costs related to a new medium voltage three-phase grid, which may have some miles long, could cripple investment to be made by the farmer as well as increase utility tariffs due to higher costs of the three-phase distribution networks in rural areas. In this context, this paper presents an innovative and low cost power supply to attend three-phase rural facilities through a new two-wire distribution system.

Giant magneto-impedance effect of two paralleled amorphous microwires

Giant magneto-impedance (GMI) is effectively enhanced by the mutual magnetic interaction between two amorphous microwires. A comparative study on GMI properties of a single wire and two wires arranged in parallel mode was reported in this work. Two-peak (TP) of impedance characteristic is presented when the dc external field changed from 0 to 320 A·m−1 in two-wire system, which is attributed to successive magnetization process in two wires induced by their magnetic interaction. And the evolution of single peak to TP phenomenon, when the distance between two wires is upto 8 mm, evidences a distance dependence of transformation from successive magnetization to simultaneous via a corresponding distance dependence of magnetostatic interactions. It is proposed that the recombination of magnetic interaction and the shielding effect results in a distance dependency of GMI response. When the distance is 8 mm, the magnetization process is close to synchronous between two wires, which give rises to higher circular permeability and better GMI response. The impedance ratio ΔZ/Z increases from 74.5 % of single wire to 172.4 % at 10 MHz. However, when the distance is upto 12 mm, the magnetic interaction is weak and magnetization process is completely independent, and GMI response decreases, relatively. This indicates that the GMI response could be effectively improved in a two-wire connection with an optical distance, which is promising and useful for the application of high-performance GMI sensors.

Dispersion relation, propagation length and mode conversion of surface plasmon polaritons in silver double-nanowire systems

We study the surface plasmon modes in a silver double-nanowire system by employing the eigenmode analysis approach based on the finite element method. Calculated dispersion relations, surface charge distributions, field patterns and propagation lengths of ten lowest energy plasmon modes in the system are presented. These ten modes are categorized into three groups because they are found to originate from the monopole-monopole, dipole-dipole and quadrupole-quadrupole hybridizations between the two wires, respectively. Interestingly, in addition to the well studied gap mode (mode 1), the other mode from group 1 which is a symmetrically coupled charge mode (mode 2) is found to have a larger group velocity and a longer propagation length than mode 1, suggesting mode 2 to be another potential signal transporter for plasmonic circuits. Scenarios to efficiently excite (inject) group 1 modes in the two-wire system and also to convert mode 2 (mode 1) to mode 1 (mode 2) are demonstrated by numerical simulations.

Two-Wire Distribution System for Supplying Three-Phase Rural Loads

Currently, the supply of electricity to rural districts is realized, in almost all cases, through single-phase medium-voltage overhead distribution lines. However, some of these installations will eventually demand the use of more expressive electrical loads, which makes the use of three-phase distribution systems a necessity, thus bringing about the substitution of the existing single-phase network. Some of the more usual techniques, based on power electronics, make the supply of three-phase loads possible from converters especially developed for single- to three-phase transformation. In this context, this article presents a new and innovative low-cost methodology, based on electromagnetic arrangements, without the use of power electronics, for attending to rural three-phase supply needs through the use of a new overhead two-wire distribution system.

1P1-D12 パラレルワイヤ駆動メカニズムと繰返し学習制御を用いた脚トルク推定システムの開発(リハビリテーションロボティクス・メカトロニクス)

Estimation of joint torque is one of motion analysis of humans; it has been applied to virtual reality, sports training and so on. This paper presents a torque estimation system for the human leg in passive motion. In this system, two wires are used to drive the human's leg in 2-DOF motion. The work space of two-wire system is analyzed, then the estimation of joint torque is demonstrated through an experiment.

A Single-Phase Inverter System for PV Power Injection and Active Power Filtering With Nonlinear Inductor Consideration

This paper proposes a single-phase two-wire inverter system for photovoltaic (PV) power injection and active power filtering (APF) with nonlinear inductor consideration. The proposed system can fully or partially perform APF, process PV power, eliminate harmonic currents, improve power factor, and take into account the nonlinear effect of its output filter inductor. In the system, even though only the utility current is sensed, both APF and maximum power point tracking features can be still achieved, reducing the number of current sensors and cost significantly. To prevent output current from exceeding switch ratings, inverter current is properly controlled through a current estimator and a defined limit circle. A self-learning algorithm is also proposed to determine nonlinear inductance, which can increase the accuracy of the estimated current. Simulations and experimental results have verified the feasibility of the proposed PV inverter system and the algorithm.