A saturable reactor in electrical engineering is a special form of inductor where the magnetic core can be deliberately saturated by a direct electric current in a control winding. Once saturated, the inductance of the saturable reactor drops dramatically. This decreases inductive reactance and allows increased flow of the alternating current (AC).
Saturable reactors provide a very simple means to remotely and proportionally control the AC through a load such as an incandescent lamp; the AC current is roughly proportional to the direct current (DC) through the control winding.
The power windings, the control winding, and the core are arranged so that the control winding is well isolated from the AC power. The AC power windings are also usually configured so that they self-cancel any AC voltage that might otherwise be induced in the control winding.
Because the required inductance to achieve dimming varies with the size of the load, saturable reactors often have multiple taps, allowing a small inductance to be used with a large load or a larger inductance to be used with a smaller load. In this way, the required magnitude of the control current can be kept roughly constant, no matter what the load.
Saturable reactors designed for mains (power-line) frequency are larger, heavier, and more expensive than electronic power controllers developed after the introduction of semiconductor electronic components, and have largely been replaced by thyristor dimmers using triacs or SCRs.
However, as of 2015, there has been renewed interest in using these devices for control of "smart grids" with multiple current tested installations in California, as well as the United Kingdom.
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This class adresses scaling laws in MEMS/NEMS. The dominant physical effects and scaling effects when downsizing sensors and actuators in microsystems are discussed, across a broad range of actuation
Le terme tôles feuilletées est employé en électrotechnique et en électronique pour désigner l'assemblage de fines tôles de fer doux ou d'acier utilisé pour la fabrication du circuit magnétique d'un certain nombre de bobines, tel que les électroaimants, les transformateurs de toutes puissances, ainsi que les pièces magnétiques de certaines machines électriques tournantes. thumb|Le feuilletage permet de réduire les pertes par courants de Foucault. Le feuilletage de tôles est fait de l'empilement de tôles d'acier, de même dimension, les unes sur les autres.
Un composant électronique est un élément destiné à être assemblé avec d'autres afin de réaliser une ou plusieurs fonctions électroniques. Les composants forment de très nombreux types et catégories, ils répondent à divers standards de l'industrie aussi bien pour leurs caractéristiques électriques que pour leurs caractéristiques géométriques. Leur assemblage est préalablement défini par un schéma d'implantation d'un circuit électronique. alt=Un transistor, composant actif, boîtier ouvert.
Seen in some magnetic materials, saturation is the state reached when an increase in applied external magnetic field H cannot increase the magnetization of the material further, so the total magnetic flux density B more or less levels off. (Though, magnetization continues to increase very slowly with the field due to paramagnetism.) Saturation is a characteristic of ferromagnetic and ferrimagnetic materials, such as iron, nickel, cobalt and their alloys. Different ferromagnetic materials have different saturation levels.
Couvre les équations, les inductances et la magnétodynamique de Maxwell, y compris les concepts d'inductance auto et mutuelle et les calculs pratiques.
Printed electronics has promised to deliver low-cost, large-area and flexible electronics for mass-market applications for some time; however, so far one limiting factor has been device performance. Over the last decade, great progress has been made in ter ...
IOP PUBLISHING LTD2020
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The invention relates to a method and a device for determining plasma characteristics, the method comprising the steps of: - arranging a measurement probe (2) having a self-inductance in proximity to a plasma (3) to establish inductive coupling between the ...
2016
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Inductive magnetic sensors are needed for tokamak operation to provide the low-frequency (LF) measurements leading to the equilibrium reconstruction and to monitor the higher frequency (HF) instabilities; the HF magnetic sensors are often also used as a ba ...