FR2554272A1 - Self-inductance coil for protecting delicate electrical and electronic installations. - Google Patents

Abstract

The invention proposes a device for protection against the effects of lightning. Such a device, which incorporates a self-inductance coil for each phase, is characterised mainly in that the self-inductance coils 10', 11' and 12' are immersed in a strongly dielectric medium 16' contained in a non-magnetic non-conducting metal tank 1' which is insulated from the ground by means of rollers made of material with a high insulating capability. Application to the protection of delicate electrical or electronic installations.

Description

 The present invention is in the field of electrical techniques and it relates to a protection device incorporating a self-inductance coil, called self, intended in particular for the protection of fragile electrical and electronic installations with regard to the effects lightning in particular.

 We know that lightning, as well as the effects it induces in conductors, in particular overhead conductors, takes the form of a wave of very short period and of fairly large amplitude, in particular of voltage, we also know that a very short period electric wave is stopped by the windings due to their self-inductance property; However, although knowing this property of the coils, we have never systematically sought, to the knowledge of the Applicant, to use it as a means of protecting electrical installations against the direct or indirect effects of lightning.

 The present invention aims to provide an appropriate device for the isolation or protection of fragile electrical and electronic or electronic installations, such as telephone installations, wireless telephone or television installations, and in general of all installations making use of electronics.

 According to the present invention a protective device incorporating a self-inductance coil intended for the protection of fragile electrical and electronic installations is generally characterized in that the coils are immersed in a highly dielectric medium contained in an enclosure said tank electrically isolated from the ground; preferably said medium consists of transformer oil; more preferably said tank is made of a good conductive metal; more preferably said metal is non-magnetic metal.

 According to a first embodiment, the coils of said plurality consist of concentrated plies. According to a second embodiment the coils are formed by co-axial windings arranged side by side.

 Preferably and generally still said windings are supported in said tank by insulating pads. Each winding passes through the wall of the tank, through standardized porcelain terminals of the transformer type. Preferably said tank comprises a terminal for earthing its wall. More preferably, the isolation of the tank from the ground is ensured by rollers-rollers made of insulating material with high insulation power. Finally, preferably each winding is surrounded by a carcass made of a material with a high dielectric coefficient.

 The triple coil cancels the overvoltage (s) in a balanced manner on all the phases and reciprocally between them, and thanks to its non-magnetic metal tank of shape close to the cube, strongly isolated from the ground this tank working in equipotential volume protection of all of the coils it contains; it should be noted that such a shape of the tank is of great importance for the proper functioning of the device.

The present invention will be better understood and details thereof will appear in the description.
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which will be made of two preferred embodiments in relation to the figures of the attached single plate, in which
Fig.l is an illustration in perspective of the device of the present invention seen from the outside,
Fig.2 is a schematic sectional illustration of a first embodiment of the device of Fig.l, and
Fige3 is a schematic sectional illustration of a second embodiment of the device in fig.l.

 In fig.l the device of the invention comprises a tank 1 made of a non-magnetic non-conductive metal; the tank has an earthing terminal for its wall and a filling orifice 3; the upper wall 4 of the tank has standardized porcelain terminals, such as 5 for the input and 6 for the output, these terminals being of the type used - for transformers.

The isolation of the tank 1 from the ground is ensured by rollers-rollers such as 7 with high insulation power the parts of these rollers which should be metallic are made of a non-magnetic metal.

 In fig.2 the terminals of each pair such as terminals 5 and 6 of the previous figure, are connected inside the tank 1 by means of a terminal such as the terminal or winding 10; three coils are therefore arranged inside the tank and in accordance with this first variant the coils are superimposed in concentric layers; each winding 10, 11, 12 is surrounded by a carcass made of a material with a high electrical coefficient, thus the carcass 13 superimposed on the winding 10, thus the carcass 14 comprised between the winding 10 and the rolling 11, etc. .. The coils and their carcass are immersed in transformer oil 16 constituting the highly dielectric medium.

In fig. 3 elements similar to those in fig. 1 are represented with the same references, these being primary; *
Finally, it is noted in the two figures of the plate that the entire carcass of one and the other variant is supported in the tank by means of insulating pads 20 or 20 '.

 It will be noted that in general the device of the invention does not comprise any element made of magnetic metal, and that all the elements which must be metallic are constituted by non-magnetic metals.

 Although we have described and shown particular embodiments, it should be understood that the scope of the present invention is not reduced to these forms but that it extends to any protection device comprising the characteristics terms indicated above.

Claims (14)

1.- Protection device incorporating a self coil  inductor, intended for the protection of electrical installations  triques and fragile electronics, characterized  in that coils are bathed  in a strongly dielectric medium contained in a  enclosure called tank electrically isolated from the ground. 2. Protection device according to claim 1, charac  terrified:  in that said medium is  consisting of transformer oil. 3.- protective device according to claim 1, charac terized  in that said tank is  made of a good conductive metal. 4.- protective device according to claim 3, charac terized  in that said metal is a  non-magnetic metal. 5. Protective device according to claim 1, charac terized  in that the coils of said  plurality consist of concentric layers. 6. Protective device according to claim 1, charac terized  in that the coils are  formed by co-axial windings arranged side by side  beside. 7. Protective device according to claim 1, charac terized  in that said windings  are supported in said tank by insulating pads.  8.- Protection device according to claim L, charac  terrified  in that each winding  passes through the wall of the tank, through terminals  in standard porcelain of the transformer type.  9. Protective device according to claim 1, charac  terrified  in that said tank comprises  a grounding terminal on its wall. 10.- Protection device according to claim 1, charac terized  in that the insulation of the  tank opposite. floor is provided by rollers  made of insulating material with high insulation power. 11. Protective device according to claim 1, charac  terrified  in that each winding  is surrounded by a carcass of material with coefficient di  high electric. 12. Protective device according to claim 1, charac terized  in that said tank has a  shape close to the cube. 13.- protective device according to claim 3, charac  terrified  in that the constituent metal  of the tank is also a non-magnetic metal. 14.- protective device according to claim 10, charac  terrified  in that the metal parts of the roller rollers are made of a non-magnetic metal.