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EP-4736201-A1 - STANDARDIZED SEGMENTED LARGE-DIAMETER ROTARY TRANSFORMER

EP4736201A1EP 4736201 A1EP4736201 A1EP 4736201A1EP-4736201-A1

Abstract

Disclosed is a rotary transformer intended to be installed around a rotatable shaft, the rotary transformer consisting of a plurality of annular stator sectors (22) and of a plurality of annular rotor sectors (24), the juxtaposition of said annular sectors forming a stator ring and a rotor ring which consist of elementary magnetic stator and rotor circuits comprising outer (40) and inner (48) magnetic cores as well as a first electrical winding (50) and a second electrical winding (52) to allow electrical energy to be transferred by electromagnetic induction between the stator and rotor rings, the inner and outer magnetic cores being separated by two air gaps e1 and e2 located on either side of the inner magnetic core, wherein the outer magnetic cores (40) are each in the form of a C-shaped claw and the inner magnetic cores (48) are each in the form of an I-shaped bar, and the outer magnetic cores (40) and/or the inner magnetic cores (48) have, at each of the air gaps, annular flared portions (44) produced by cutting into adjacent sectors a magnetic circular ring (46) formed of a radial stack of circular metal sheets advantageously provided with notches to facilitate their assembly on the outer and inner magnetic cores.

Inventors

  • HADJIDJ, DJEMOUAI
  • BELFKIRA, Rachid

Assignees

  • Safran Electrical & Power

Dates

Publication Date
20260506
Application Date
20240619

Claims (10)

  1. [Claim 1] A rotating transformer (10) intended to be installed around a rotating movable shaft (12), the rotating transformer consisting of a plurality of external stator annular sectors (22) and a plurality of internal rotor annular sectors (24), the juxtaposition over 360° of these external stator and internal rotor annular sectors forming an external stator ring and an internal rotor ring consisting of elementary stator and rotor magnetic circuits, the internal rotor annular sectors being inserted axially into the external stator annular sectors, each of the elementary stator magnetic circuits comprising an external magnetic core (30; 40) and a first electrical winding (32; 50, 54) and each of the elementary rotor magnetic circuits comprising an internal magnetic core (34; 48) and a second electrical winding (36; 52, 56) to allow a transfer of electrical energy by electromagnetic induction between the external stator and internal rotor rings. rotor, the internal and external magnetic cores being mounted concentrically and separated by two axial air gaps e1 and e2 present on either side of the internal magnetic core (48), characterized in that the external magnetic cores (40) each have a C-claw shape and the internal magnetic cores (48) each have an I-bar shape and in that the external magnetic cores (40) and/or the internal magnetic cores (48) have at each of the air gaps annular expansions (44) produced by cutting into adjacent sectors a circular magnetic ring (46) formed from a radial stack of circular sheets.
  2. [Claim 2] A rotating transformer according to claim 1, wherein the inner and outer magnetic cores (30, 40; 34, 48) are formed from a radial stack of wound sheets of a magnetic material. of amorphous or nanocrystalline type or of a block of magnetic powder made of amorphous powder.
  3. [Claim 3] A rotating transformer according to claim 1 or claim 2, wherein to enable the insertion of the internal magnetic core into the external magnetic core and the creation of the air gaps on either side of the internal magnetic core, the C-shaped external magnetic core (40) is produced by cutting to the size of the internal magnetic core, the annular expansions and the air gaps, a standard oblong-shaped magnetic element (42) consisting of a radial stack of wound sheets.
  4. [Claim 4] A rotating transformer according to any one of claims 1 to 3, wherein the number of annular sectors on the stator is or is not the same as the number of annular sectors on the rotor.
  5. [Claim 5] A rotating transformer according to any one of claims 1 to 4, wherein the number of external magnetic cores per external stator annular sector is or is not the same as the number of internal magnetic cores per internal rotor annular sector.
  6. [Claim 6] A rotating transformer according to any one of claims 1 to 5, wherein the annular expansions comprise notches (44a, 44b, 44c, 44d) to facilitate their assembly on the internal or external magnetic cores.
  7. [Claim 7] A rotating transformer according to any one of claims 1 to 6, wherein the stator winding which may be wire or ribbon winding is either a concentric winding around each external magnetic core or a single winding (54) surrounding all the external magnetic cores of a given annular sector and the rotor winding which may be wire or ribbon winding is either a concentric winding around each internal magnetic core or a single winding (56) surrounding all the internal magnetic cores of a given annular sector.
  8. [Claim 8] A rotating transformer according to any one of claims 1 to 7, wherein the outer stator annular sectors are identical and interchangeable with each other and/or the inner rotor annular sectors are identical and interchangeable with each other.
  9. [Claim 9] A rotating transformer according to any one of claims 1 to 8, wherein the external annular stator sectors are electrically interconnected with each other by flexible interconnection parts accessible for assembly/disassembly through circumferential access hatches (14A) and/or the internal annular rotor sectors are electrically interconnected with each other by flexible interconnection parts accessible for assembly/disassembly through circumferential access hatches (14A).
  10. [Claim 10] Use of a rotating transformer according to any one of claims 1 to 9 for the electrical de-icing of the propeller blades of an aircraft turbomachine.

Description

Description Title of the invention: Large diameter standardized segmented rotating transformer Technical Domain The present invention relates to the field of power transfer between a fixed reference point and a rotating reference point for the electrical (electrothermal) defrosting of the propeller blades of an aircraft turbomachine and relates to a single-phase rotating transformer used in a harsh environment for the contactless transmission of electrical energy by electromagnetic induction between first and second electrical windings of this transformer. Previous technique On electric or hybrid aircraft as on conventional aircraft, there are several surfaces to be protected against frost on the fixed and rotating parts of the turbomachine. The protection envisaged for the rotating parts is generally exclusively electrothermal based on electric heating mats formed of resistance layers covering the surfaces to be protected. To ensure the transfer of power and therefore to convey the electrical energy from the fixed part to the rotating part where the electric heating mats are installed, it is known to use a device called a "slip ring" whose principle consists in rubbing several fixed conductive rings secured to the fixed part on circular conductive tracks secured to the rotating part, in order to create an electrical connection between the fixed part and the rotating part of the turbomachine. However, the major drawback of this solution lies in its very limited service life due to the wear of the parts in continuous friction, which therefore generates unacceptable operating costs on a single-aisle commercial aircraft of the A320 or B737 type where the rotating part endures multiple rotations. Furthermore, it is known that due to the harsh environment (thermal, electromagnetic and vibration) existing in hybrid aircraft with numerous electrified engine loads, the integration of electrical equipment is a major challenge and must meet multiple constraints linked both to accessibility for assembly/disassembly and to the routing of power cables with large bending radii and servitudes such as cooling. There is therefore a current need for a reliable and long-life solution for transferring power from a fixed reference to a rotating reference applicable to large diameter rotation shafts and in compliance with the constraints of under-wing line replaceable equipment (LRU: Line Replaceable Unit). Disclosure of the invention The main purpose of the present invention is therefore a large diameter rotating transformer, segmented into quarters, whose maintenance is facilitated and does not interfere with the other systems and modules of the aircraft turbomachine, despite its installation in a confined, constrained and difficult to access area. Another purpose is to propose a transformer allowing simplified but robust control. Yet another purpose is to allow industrialization of this rotating transformer at a lower cost, while limiting material waste during manufacturing. These aims are achieved by a rotating transformer intended to be installed around a rotating movable shaft, the rotating transformer being made up of a plurality of external annular stator sectors and a plurality of internal annular rotor sectors, the juxtaposition over 360° of these external annular stator and internal rotor sectors forming an external stator ring and an internal rotor ring made up of a set of elementary stator and rotor magnetic circuits, each of the elementary stator magnetic circuits comprising an external magnetic core and a first electrical winding and each of the elementary rotor magnetic circuits comprising an internal magnetic core and a second electrical winding to allow a transfer of electrical energy by electromagnetic induction between the outer stator and inner rotor rings, the inner and outer magnetic cores being mounted concentrically and separated by two air gaps present on either side of the inner magnetic core, the outer magnetic cores each have a C-claw shape and the inner magnetic cores each have an I-bar shape and in that the outer magnetic cores and/or the inner magnetic cores have at each of the air gaps annular expansions produced by cutting into adjacent sectors a circular magnetic ring formed from a radial stack of circular sheets. Thus, with this contactless power transfer, an improvement in the reliability, lifetime and operating cost of the transformer is obtained. In addition, better accessibility to the transformer is possible facilitating its integration into the systems and modules of the aircraft turbomachine. Such a rotating transformer is advantageously used for the electrical de-icing of the propeller blades of an aircraft turbomachine. Preferably, the internal and external magnetic cores are formed from a radial stack of wound sheets of a magnetic material of the amorphous or nanocrystalline type or from a block of magnetic powder made from amorphous powder. According to the embodiment envisaged, t