Without having further context at hand, I assume that the "tore" is a toroidal transformer, perhaps used as instrument transformer.

Toroidal transformers are built around a ring-shaped core, which, depending on operating frequency, is made from a long strip of silicon steel or permalloy wound into a coil, powdered iron, or ferrite.[61][62] A strip construction ensures that the grain boundaries are optimally aligned, improving the transformer's efficiency by reducing the core's reluctance. The closed ring shape eliminates air gaps inherent in the construction of an E-I core.[21] The cross-section of the ring is usually square or rectangular, but more expensive cores with circular cross-sections are also available. The primary and secondary coils are often wound concentrically to cover the entire surface of the core. This minimizes the length of wire needed and provides screening to minimize the core's magnetic field from generating electromagnetic interference.
https://en.m.wikipedia.org/wiki/Transformer

Toroidal inductors and transformers are used in a wide range of electronic circuits: power supplies, inverters, and amplifiers, which in turn are used in the vast majority of electrical equipment: TVs, radios, computers, and audio systems.
https://en.m.wikipedia.org/wiki/Toroidal_inductors_and_trans...

Using a toroidal, or donut-shaped core allows a reduction in the size and weight of a transformer by 20% to 50% compared with conventional cores with-out sacrificing performance.This is possible because core losses in toroids are typically 10% to 20% of the total power loss, with the balance being lost in the windings. Toroids are commonly used for current and instrument transformers, where low losses are extremely important. 
https://www.amgistoroids.com/Toroidal_technology

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Note added at 1 day 1 hr (2019-02-05 17:32:45 GMT)
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If you cannot determine the purpose or application of the "tore" you may translate literally as "torus" or "toroid", referring to the shape.

L'invention concerne un tore de ferrite amélioré notamment destiné à des translateurs.
The invention relates to an improved ferrite core, which is suitable in particular for transformers.

L'interface patient comprend également un cadre présentant une portion en forme de tore formant une ouverture.
The patient interface further includes a frame having a torus shaped portion defining an opening.

Chaque tore comprend une pluralité de nœuds.
Each torus includes a plurality of nodes.

Un fil conducteur est acheminé à travers le tore bobiné du transformateur de courant différentiel.
A wire conductor is routed through the toroid of the differential current transformer.
https://context.reverso.net/traduction/francais-anglais/tore