A Simple Formula for the Calculation of Peak Values of Currents Induced in Overhead Lines by Indirect Lightning Strokes. Theory and Experimental Validation

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The evaluation and the analysis of the lightning electromagnetic pulse (LEMP) response of distribution networks require the availability of accurate models of LEMP-illuminated lines and their implementation into software tools able to calculate lightning-induced electromagnetic transients in distribution systems having complex configuration. This paper deals indeed with a computer code, LIOV (lightning induced overvoltage code), and with two interfaces recently realized between it and (a) the DCG/EPRI EMTP9

Neoclassical tearing modes are driven by the reduction of bootstrap current inside the island due to the flattening of the pressure profile. This current perturbation enhances the magnetic perturbation responsible for the island formation. Therefore it is well known that local current drive (CD) can be used to compensate this perturbation and stabilize the mode. Several forms of the current drive contribution to the modified Rutherford equation have been proposed. Analytical fits of these contributions are

The development of linear model of the present JET (Joint European Torus) electromagnetic system has allowed the design of an optimized Plasma Shape Controller. Quite extreme plasma boundaries (elongation k = 1.9 and triangularity = 0.6) are shown to be controllable also in the presence of large variations of the values of poloidal beta (0.1 < beta(p) < 0.6) and/or internal magnetic inductance (0.8 < l(i) < 1.4). The developed model gives also an excellent simulation of the growth rate of the experi

The CONDOPT (CONDuctor OPTimization) experiment has been recently completed in SULTAN. The current sharing behavior of Nb-3 Sn samples was assessed as a function of the number of cyclic loads experienced during current sweeps in a 10 T background field. We present here results of a computer analysis performed with the code THEA(TM) (for consistent Thermal, Hydraulic and Electric Analysis) in support of the interpretation of the experimental results. We focus in particular on the critical current and current

Feasibility studies performed in the last years have shown that the use of the low voltage distribution network can be used for data transmission. The main problem is the possible radiation of electromagnetic field and the disturbances which can affect radio transmission in the 1 to 30 MHz frequency band. The paper presents the difficulties to choose a limit for the field radiated by this technology and also to find a suitable method for checking that the limit is respected in case of conflict. It presents

Ion cyclotron heating and current drive at omega approximate to 2omega(cH) in JET deuterium plasmas with a hydrogen concentration n(H)/(n(D)+n(H)) in the range of 5-15% are analysed, comparing results of numerical computer modelling with experiments. Second harmonic hydrogen damping is found to be maximized by placing the resonance on the, low-field side (LFS) of the torus, which minimizes competing direct electron damping and parasitic high-harmonic D damping in the presence of D beams. The shape of the ca

The Laboratory of Electrical Machines of the Swiss Federal Institute of Technology (Lausanne) has developed a software (TLSim) for the simulation of electrical urban transportation systems. This program can simulate the behaviour of the power supply network (current and voltage level at any point of the topology) comprising uni- and bi- directionnal sub-stations. In the network the vehicules (trolleybus) may run along any defined path through different electrical supply sectors. Several models of trolleybus

We propose in this paper new expressions relating lightning return stroke currents and far radiated electric and magnetic fields, taking into account the presence of an elevated strike object. The derived expressions show that the presence of an elevated strike object enhances the radiated electromagnetic field. The enhancement with respect to a return stroke initiated at ground level is expressed simply through a factor equal to (1+c/v), where v and c are the return stroke speed and the speed of light, res

Besides the option of HTS cables as retrofit elements in densely populated areas, the technically most attractive aspect of HTS is the possibility of high power transmission at reduced voltage. In this paper we concentrate on this second aspect. High power/low voltage HTS lines are analysed from the technical and economical point of view in two case studies: (i) a 110 kV/1 GVA transalpine line replacing a 380 kV overhead line and (ii) a 30 km/600 MVA line connecting a nuclear power plant with a densely popu

Flexible AC Transmission Systems (FACTS) are systems based on power electronics using GTO or IGCT semiconductors [1] that allow a better use of the transfer capacities of the transmission lines and permit to satisfy the requirements due to the liberalization of the electrical energy market. The Unified Power Flow Controller (UPFC) is one of the most versatile topologies of the FACTS family. The UPFC can be decomposed in two different power circuits: the parallel one maintaining the network bus voltage by co

A review with 348 refs. In 1985, Car and Parrinello published a seminal article on an "Unified approach for mol. dynamics and d. functional theory". This paper established a basis for parameter-free mol. dynamics simulations in which all the interactions are calcd. on the fly via a first-principles quantum mech. method. In the 15 yr of its existence, the Car-Parrinello method has found widespread applications that expanded rapidly from physics to chem. and, most recently, even into biol. In this article, th

Superconductors of type-II are partially penetrated by magnetic flux, where the pinning of flux tubes constitutes a memory that gives rise to a hysteresis. However, the hysteresis gradually disappears when a transport current approaches the critical current. This paper investigates what possibilities and limitations the Preisach model has to describe this hysteresis. Previous results are complimented by demonstrating the limitation to higher harmonics, the computation of an inverse model including an induct

A Simple Formula for the Calculation of Peak Values of Currents Induced in Overhead Lines by Indirect Lightning Strokes. Theory and Experimental Validation

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Lightning-induced voltages on complex distribution systems: models, advanced software tools and experimental validation

On the contribution of local current density to neoclassical tearing mode stabilization

Upgrade of the present JET shape and vertical stability controller

Application of the code THEA to the CONDOPT experiment in SULTAN

Problems related to the definition of appropriate limits for radiated emissions due to power line communications

Analysis of ion cyclotron heating and current drive at omega approximate to 2 omega(cH) for sawtooth control in JET plasmas

TLSim: A software for Electrical Public Transportation Systems

On the enhancement of radiated electric and magnetic fields associated with lightning return strokes to tall structures

Technical and Economical Assessment of HTS Cables

Investigation of the 3-Level Unified Power Flow Controller (UPFC)

15 years of Car-Parrinello simulations in physics, chemistry and biology

Possibilities and limitations of using Preisach model for hysteresis in superconductors