A rotary transformer

Abstract

A rotary transformer (100a-b) for the transfer of electrical signals to a rotor (802) of an electric rotating machine (800). The rotary transformer (100a-b) comprises a stationary unit (102) and a rotatable unit (104) rotatable about an axis of rotation (105) in relation to the stationary unit (102). The stationary unit (102) comprises a first core part (106a- b) comprising a first compartment (130) holding one or more primary windings (108) of the rotary transformer (100a-b). The rotatable unit (104) comprises a second core part (110a-b) comprising a second compartment (118) holding one or more secondary windings (112). The rotary transformer (100a-b) comprises an inlet (142), for a cooling fluid to cool one or more of the stationary unit (102) and rotatable unit (104), and an outlet (144) for the cooling fluid. One of the first and second core parts (106a-b, 110a- b) comprises a first conduit (146) for guiding the cooling fluid to one of the first and second compartments (130, 118). The first conduit (146) is connected to the inlet (142) of the rotary transformer (100a-b).

Description

[0001] A ROTARY TRANSFORMER

[0002] Technical field

[0003] Aspects of the present invention relate to a rotary transformer for the transfer of electrical signals to a rotor of an electric rotating machine.

[0004] Background

[0005] In general, an electric rotating machine comprises a stator and a rotor rotatable about an axis of rotation in relation to the stator. In general, at least one of the rotor and stator may be provided with one or more windings, one or more permanent magnets, or one or more other elements interacting with the stator or rotor. Some electric rotating machines are equipped with a fluid system for cooling one or more of the rotor and stator, since during operation of the electric rotating machine one or more of the rotor and stator may be heated to such a degree that cooling is advisable. Some electric rotating machines may be provided with a rotary transformer to transfer electrical signals to the rotor of the electric rotating machine. Some rotary transformers may be equipped with a fluid system for cooling the rotary transformer.

[0006] Summary

[0007] The inventors of the present invention have found drawbacks in conventional rotary transformers for the transfer of electrical signals to the rotor of an electric rotating machine. For example, the cooling of some conventional rotary transformers is not efficient enough.

[0008] An object of the invention is to provide a solution which mitigates or solves the drawbacks and problems of conventional solutions.

[0009] The above and further objects are solved by the subject matter of the independent claims. Further advantageous embodiments of the invention can be found in the dependent claims. According to a first aspect of the invention, the above mentioned and other objects are achieved with a rotary transformer for the transfer of electrical signals to a rotor of an electric rotating machine, wherein the rotary transformer comprises a stationary unit, and a rotatable unit rotatable about an axis of rotation in relation to the stationary unit, wherein the stationary unit comprises a first core part comprising a first compartment holding one or more primary windings of the rotary transformer, wherein the rotatable unit comprises a second core part comprising a second compartment holding one or more secondary windings of the rotary transformer, wherein the first core part is annular and configured to surround the axis of rotation, wherein the second core part is annular and configured to surround and to rotate about the axis of rotation, wherein the first core part and the second core part form a gap between one another, wherein the rotary transformer comprises an inlet for a cooling fluid so as to cool one or more of the stationary unit and rotatable unit, wherein the rotary transformer comprises an outlet for the cooling fluid, wherein one of the first and second core parts comprises a first conduit for guiding the cooling fluid to one of the first and second compartments, and wherein the first conduit is connected to the inlet of the rotary transformer.

[0010] An advantage of the rotary transformer according to the first aspect is an improved cooling of the rotary transformer, since by way of the first conduit, cooling fluid is more efficiently guided to and / or from the first or second compartment and the windings located therein. An advantage of the rotary transformer according to the first aspect is an improved cooling of one or more of the stationary and rotatable units of the rotary transformer, since by way of the first conduit, cooling fluid is more efficiently guided to and / or from the first or second compartment and the windings located therein. An advantage of the rotary transformer according to the first aspect is an improved transfer of electrical signals to and / or from the rotor of an electric rotating machine, for example because of the improved cooling. An advantage of the rotary transformer according to the first aspect is that an improved rotary transformer is provided, for example because of the improved cooling. An advantage of the rotary transformer according to the first aspect is an improved electric rotating machine by providing the electric rotating machine with the innovative rotary transformer, for example because of the improved cooling.

[0011] The electrical signals transferred by the rotary transformer may comprise electrical energy, electric current, and / or electric signals including data or information.

[0012] According to an advantageous embodiment of the rotary transformer according to the first aspect, the first core part comprises the first conduit for guiding the cooling fluid to the first compartment. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of one or more of the stationary and rotatable units of the rotary transformer. However, for other embodiments, the second core part may comprise the first conduit for guiding the cooling fluid to the second compartment.

[0013] According to a further advantageous embodiment of the rotary transformer according to the first aspect, the first conduit is configured to guide the cooling fluid to the first compartment for cooling one or more of the first core part and primary winding. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of the stationary unit of the rotary transformer.

[0014] According to another advantageous embodiment of the rotary transformer according to the first aspect, the first conduit is connected to the outlet of the rotary transformer. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of one or more of the stationary and rotatable units of the rotary transformer. According to yet another advantageous embodiment of the rotary transformer according to the first aspect, the first conduit is further configured to guide one or more electrical connections for one or more of the primary and secondary windings. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of one or more of the stationary and rotatable units of the rotary transformer. An advantage of this embodiment is a less complex rotary transformer since fewer conduits are needed.

[0015] According to still another advantageous embodiment of the rotary transformer according to the first aspect, the rotary transformer comprises one or more electrical connections for one or more of the primary and secondary windings, wherein at least one or more portions of the one or more electrical connections is / are positioned in the first conduit. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of one or more of the stationary and rotatable units of the rotary transformer. An advantage of this embodiment is a less complex rotary transformer since fewer conduits are needed. Further, space is saved by using the first conduit for both cooling fluid and electrical connections.

[0016] According to an advantageous embodiment of the rotary transformer according to the first aspect, the first conduit has a first mouth opening to one of the first and second compartments, wherein in one of the first and second compartments a first space is formed between one or more conductors of one or more of the primary and secondary windings at the first mouth of the first conduit so as to let in cooling fluid into one of the first and second compartments from the first conduit via the first mouth of the first conduit. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of one or more of the stationary and rotatable units of the rotary transformer. According to a further advantageous embodiment of the rotary transformer according to the first aspect, in one of the first and second compartments one or more second spaces is / are formed between one or more conductors of one or more of the primary and secondary windings for the guidance of the cooling fluid in one or more of the first and second compartments. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of one or more of the stationary and rotatable units of the rotary transformer.

[0017] According to another advantageous embodiment of the rotary transformer according to the first aspect, one of the first and second core parts comprises a second conduit for guiding the cooling fluid away from one of the first and second compartments, wherein the second conduit is connected to the outlet of the rotary transformer. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer, since by way of the second conduit, cooling fluid is more efficiently guided away from the first or second compartment and the windings located therein. An advantage of this embodiment is a further improved cooling of one or more of the stationary and rotatable units of the rotary transformer, since by way of the second conduit, cooling fluid is more efficiently guided away from the first or second compartment and the windings located therein.

[0018] According to yet another advantageous embodiment of the rotary transformer according to the first aspect, the first core part comprises the second conduit for guiding the cooling fluid away from the first compartment. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of the stationary unit of the rotary transformer.

[0019] According to still another advantageous embodiment of the rotary transformer according to the first aspect, the second conduit is further configured to guide one or more electrical connections for one or more of the primary and secondary windings. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of one or more of the stationary and rotatable units of the rotary transformer. An advantage of this embodiment is a less complex rotary transformer since fewer conduits are needed.

[0020] According to an advantageous embodiment of the rotary transformer according to the first aspect, the rotary transformer comprises one or more electrical connections for one or more of the primary and secondary windings, wherein at least one or more portions of the one or more electrical connections is / are positioned in the second conduit. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of one or more of the stationary and rotatable units of the rotary transformer. An advantage of this embodiment is a less complex rotary transformer since fewer conduits are needed.

[0021] According to a further advantageous embodiment of the rotary transformer according to the first aspect, the second conduit has a first mouth opening to one of the first and second compartments, wherein in one of the first and second compartments a third space is formed between one or more conductors of one or more of the primary and secondary windings at the first mouth of the second conduit so as to let out cooling fluid from one of the first and second compartments to the second conduit via the first mouth of the second conduit. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of the stationary unit of the rotary transformer.

[0022] According to another advantageous embodiment of the rotary transformer according to the first aspect, the first compartment is annular, wherein the second compartment is annular, wherein the first conduit has a first mouth opening to one of the first and second compartments, wherein one of the stationary unit and rotatable unit comprises a curved partition positioned in one of the first and second compartments, and wherein the curved partition and walls of one of the first and second compartments form a curved channel for guiding the cooling fluid from the first mouth of the first conduit and about the axis of rotation.

[0023] An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of the stationary unit of the rotary transformer. An advantage of this embodiment is an improved guidance of the cooling fluid in the first or second compartment, and thus an improved cooling of one or more of the rotary transformer, stationary unit, rotary unit, primary winding and secondary winding.

[0024] According to yet another advantageous embodiment of the rotary transformer according to the first aspect, the curved channel comprises two or more annular paths for the cooling fluid, wherein the two or more annular paths extend around the axis of rotation, wherein one of the two or more annular paths is radially inside another one of the two or more annular paths, and wherein the curved channel is configured to guide the cooling fluid from said one of the two or more annular paths being radially inside another one of the two or more annular paths to said other one of the two or more annular paths being radially outside one of the two or more annular paths.

[0025] An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of the stationary unit of the rotary transformer. An advantage of this embodiment is an improved guidance of the cooling fluid in the first or second compartment, and thus an improved cooling of one or more of the rotary transformer, stationary unit, rotary unit, primary winding and secondary winding.

[0026] According to still another advantageous embodiment of the rotary transformer according to the first aspect, said one of the two or more annular paths being radially inside another one of the two or more annular paths comprises the first mouth of the first conduit. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of the stationary unit of the rotary transformer. An advantage of this embodiment is an improved guidance of the cooling fluid in the first or second compartment, and thus an improved cooling of one or more of the rotary transformer, stationary unit, rotary unit, primary winding and secondary winding.

[0027] According to an advantageous embodiment of the rotary transformer according to the first aspect, wherein the second conduit has a first mouth opening to one of the first and second compartments, wherein said other one of the two or more annular paths being radially outside one of the two or more annular paths comprises the first mouth of the second conduit, and wherein the curved channel is configured to guide the cooling fluid from the first mouth of the first conduit to the first mouth of the second conduit.

[0028] An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of the stationary unit of the rotary transformer. An advantage of this embodiment is an improved guidance of the cooling fluid in the first or second compartment, and thus an improved cooling of one or more of the rotary transformer, stationary unit, rotary unit, primary winding and secondary winding.

[0029] According to a further advantageous embodiment of the rotary transformer according to the first aspect, the curved channel comprises a first end region and a second end region, wherein the curved channel has an elongated extension extending around the axis of rotation from the first end region of the curved channel to the second end region of the curved channel, wherein the first end region of the curved channel comprises the first mouth of the first conduit, and wherein the curved channel is configured to guide the cooling fluid from the first end region of the curved channel to the second end region of the curved channel. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of the stationary unit of the rotary transformer. An advantage of this embodiment is an improved guidance of the cooling fluid in the first or second compartment, and thus an improved cooling of one or more of the rotary transformer, stationary unit, rotary unit, primary winding and secondary winding.

[0030] According to another advantageous embodiment of the rotary transformer according to the first aspect, the second end region of the curved channel comprises the first mouth of the second conduit. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of the stationary unit of the rotary transformer. An advantage of this embodiment is an improved guidance of the cooling fluid in the first or second compartment, and thus an improved cooling of one or more of the rotary transformer, stationary unit, rotary unit, primary winding and secondary winding.

[0031] According to still another advantageous embodiment of the rotary transformer according to the first aspect, said one of the two or more annular paths being radially inside another one of the two or more annular paths comprises the first end region of the curved channel. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of the stationary unit of the rotary transformer. An advantage of this embodiment is an improved guidance of the cooling fluid in the first or second compartment, and thus an improved cooling of one or more of the rotary transformer, stationary unit, rotary unit, primary winding and secondary winding.

[0032] According to yet another advantageous embodiment of the rotary transformer according to the first aspect, said other one of the two or more annular paths being radially outside one of the two or more annular paths comprises the second end region of the curved channel. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of the stationary unit of the rotary transformer. An advantage of this embodiment is an improved guidance of the cooling fluid in the first or second compartment, and thus an improved cooling of one or more of the rotary transformer, stationary unit, rotary unit, primary winding and secondary winding.

[0033] According to an advantageous embodiment of the rotary transformer according to the first aspect, one of the stationary unit and rotatable unit comprises a cover covering one of the first and second compartments, wherein one or more of the primary and secondary windings is enclosed by the cover and one of the first and second core parts. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a further improved cooling of the stationary unit of the rotary transformer. An advantage of this embodiment is an improved guidance of the cooling fluid in the first or second compartment, and thus an improved cooling of one or more of the rotary transformer, stationary unit, rotary unit, primary winding and secondary winding.

[0034] According to a further advantageous embodiment of the rotary transformer according to the first aspect, the curved partition is attached to the cover. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a facilitated assembly of the rotary transformer.

[0035] According to another advantageous embodiment of the rotary transformer according to the first aspect, the curved partition is integrally formed with the cover. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a facilitated manufacture and assembly of the rotary transformer.

[0036] According to yet another advantageous embodiment of the rotary transformer according to the first aspect, one or more of the cover and curved partition is / are made of a material comprising or consisting of a polymer or a polymer composite. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is a facilitated manufacture and assembly of the rotary transformer.

[0037] According to still another advantageous embodiment of the rotary transformer according to the first aspect, the first compartment opens in a direction toward the second core part while the second compartment opens in a direction toward the first core part.

[0038] According to an advantageous embodiment of the rotary transformer according to the first aspect, the first core part has a first side facing the second core part, wherein the first core part has a second side facing away from the second core part, wherein at the first side of the first core part the first core part comprises the first compartment, wherein the second core part has a first side facing the first core part, wherein the second core part has a second side facing away from the first core part, and wherein at the first side of the second core part the second core part comprises the second compartment.

[0039] According to a further advantageous embodiment of the rotary transformer according to the first aspect, the first conduit has a first mouth opening to one of the first and second compartments, wherein the first conduit has a second mouth at the second side of one of the first and second core part. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer.

[0040] According to another advantageous embodiment of the rotary transformer according to the first aspect, the second conduit has a first mouth opening to one of the first and second compartments, wherein the second conduit has a second mouth at the second side of one of the first and second core part. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer.

[0041] According to still another advantageous embodiment of the rotary transformer according to the first aspect, the rotary transformer comprises a casing housing the stationary unit and the rotatable unit. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer. An advantage of this embodiment is an improved guidance of the cooling fluid, and thus an improved cooling of the rotary transformer.

[0042] According to yet another advantageous embodiment of the rotary transformer according to the first aspect, the rotary transformer comprises a cooling fluid system for the cooling of one or more of the stationary unit and rotatable unit, wherein the cooling fluid system comprises one or more of the group of:

[0043] • the first chamber;

[0044] • the second chamber;

[0045] • the inlet;

[0046] • the outlet;

[0047] • the first conduit;

[0048] • the second conduit;

[0049] • the first space;

[0050] • the second space;

[0051] • the third space;

[0052] • the curved channel;

[0053] • the two or more annular paths; and

[0054] • the casing.

[0055] According to an advantageous embodiment of the rotary transformer according to the first aspect, one or more of the first and second core parts is / are made of a ferromagnetic or ferrimagnetic material. An advantage of this embodiment is a further improved rotary transformer. According to a further advantageous embodiment of the rotary transformer according to the first aspect, the outer radius of the second core part is equal to the outer radius of the first core part. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer.

[0056] According to another advantageous embodiment of the rotary transformer according to the first aspect, the inner radius of the second core part is equal to the inner radius of the first core part. An advantage of this embodiment is a further improved rotary transformer. An advantage of this embodiment is a further improved cooling of the rotary transformer.

[0057] According to a second aspect of the invention, the above mentioned and other objects are achieved with an electric rotating machine comprising a stator, a rotor rotatable about an axis of rotation in relation to the stator, and a rotary transformer according to any one of the embodiments disclosed above or below.

[0058] Advantages of the electric rotating machine according to the second aspect and its embodiments correspond to the above- or below-mentioned advantages of the rotary transformer according to the first aspect and its embodiments.

[0059] According to a third aspect of the invention, the above mentioned and other objects are achieved with a vehicle comprising one or more of the group of:

[0060] • a rotary transformer according to any one of the embodiments disclosed above or below; and

[0061] • an electric rotating machine according to any one of the embodiments disclosed above or below. Advantages of the vehicle according to the third aspect and its embodiments correspond to the above- or below-mentioned advantages of the rotary transformer according to the first aspect and its embodiments.

[0062] The vehicle may be a wheeled vehicle, i.e. a vehicle having wheels. The vehicle may for example be a bus, a tractor vehicle, a heavy vehicle, a truck, or a car. The tractor vehicle, and / or the truck, may, or may be configured to, haul, or pull, a trailer. However, other types of vehicles are possible. The vehicle may be referred to as a motor vehicle. The vehicle may be an electric vehicle, EV, for example a hybrid vehicle or a hybrid electric vehicle, HEV, or a battery electric vehicle, BEV. Thus, a hybrid electric vehicle, HEV, and a battery electric vehicle, BEV, are versions, or examples, of an electric vehicle, EV. The EV may comprise one or more electric rotating machines or electric motors. The vehicle may comprise a combustion engine. For some embodiments, the vehicle may include only a combustion engine for the propulsion of the vehicle.

[0063] The vehicle may comprise a powertrain. The powertrain may be configured in accordance with any one of the embodiments disclosed above or below. The powertrain of the vehicle may comprise one or more of the group of: a combustion engine; an electric battery cell unit; an electric battery arrangement; and an electric battery pack.

[0064] The above-mentioned features and embodiments of the rotary transformer, the electric rotating machine and the vehicle, respectively, may be combined in various possible ways providing further advantageous embodiments.

[0065] Further advantageous embodiments of the rotary transformer, the electric rotating machine and the vehicle according to the present invention and further advantages with the embodiments of the present invention emerge from the detailed description of embodiments. Brief Description of the Drawings

[0066] Embodiments of the invention will now be illustrated, for exemplary purposes, in more detail by way of embodiments and with reference to the enclosed drawings, where similar references are used for similar parts, in which:

[0067] Figure 1 is a schematic circuit diagram illustrating aspects of embodiments of the rotary transformer according to the first aspect of the invention and of the of the electric rotating machine according to the second aspect of the invention;

[0068] Figure 2 is a schematic sectional side view of an embodiment of the rotary transformer according to the first aspect of the invention;

[0069] Figure 3 is a schematic sectional side view of another embodiment of the rotary transformer according to the first aspect of the invention;

[0070] Figure 4 schematically illustrates cross-section views of alternative structures of the stationary and rotatable units of embodiments of the rotary transformer according to the first aspect of the invention;

[0071] Figure 5 is a schematic sectional perspective view of the stationary and rotatable units of an embodiment of the rotary transformer according to the first aspect of the invention;

[0072] Figure 6A is a schematic perspective view of an embodiment of the first core part or the second core part of an embodiment of the rotary transformer according to the first aspect of the invention;

[0073] Figure 6B is a schematic side view of the first or second core part of figure 6A;

[0074] Figure 6C is a schematic bottom view of the first or second core part of figure 6A;

[0075] Figure 7 is a schematic sectional view of an embodiment of the rotary transformer according to the first aspect of the invention;

[0076] Figure 8 is a schematic bottom view of an embodiment of the stationary unit of an embodiment of the rotary transformer according to the first aspect of the invention;

[0077] Figure 9A is a schematic sectional bottom view of an embodiment of the one or more primary or secondary windings of an embodiment of the rotary transformer according to the first aspect of the invention; Figure 9B is a schematic sectional bottom view of the one or more primary or secondary windings of a conventional rotary transformer according to conventional technology;

[0078] Figure 10 is a schematic sectional bottom view of an embodiment of the stationary unit of an embodiment of the rotary transformer according to the first aspect of the invention, including the one or more primary windings of figure 9A;

[0079] Figure 1 1 is a schematic end view of an embodiment of the electric rotating machine according to the second aspect of the invention;

[0080] Figure 12 schematically illustrates a cross-section of the electric rotating machine along D-D in figure 1 1 ;

[0081] Figure 13 is a schematic diagram illustrating an embodiment of a fluid system for cooling one or more of the rotor and stator of an embodiment of the electric rotating machine according to the second aspect of the invention; and

[0082] Figure 14 is a schematic side view of an embodiment of the vehicle according to the third aspect.

[0083] Detailed Description

[0084] Figure 1 shows a schematic circuit diagram illustrating general aspects of embodiments of the rotary transformer 10Oa-b for the transfer of electrical signals to a rotor 810 of an electric rotating machine 800 according to the first aspect of the invention. The electrical signals transferred by the rotary transformer 100a-b may comprise electrical energy, electric current, and / or electric signals including data or information. The circuit diagram also illustrates general aspects of embodiments of the electric rotating machine 800 according to the second aspect of the invention. A stator 806 of the electric rotating machine 800 may be provided with electrical energy from an electric battery arrangement 906 via a first power converter 702. The first power converter 702 is configured to convert DC power from the electric battery arrangement 906 to AC power to be provided to the stator 806 of the electric rotating machine 800 and / or configured to convert AC power from the stator 806 of the electric rotating machine 800 to DC power to be provided to the electric battery arrangement 906. For some embodiments, the first power converter 702 may be referred to as an inverter. The rotary transformer 100a-b may be connectable, or connected, more specifically electrically connected, to the electric battery arrangement 906 via a second power converter 704, which may be referred to as a rotor current controller and / or an inverter. The rotary transformer 100a-b may be connectable, or connected, more specifically electrically connected, to the rotor 810 of an electric rotating machine 800 via a third power converter 706, which may be referred to as a rotating rectifier. The second power converter 704 may be configured to convert DC power from the electric battery arrangement 906 to AC power to be provided to rotary transformer 100a-b and / or configured to convert AC power from the rotary transformer 10Oa-b to DC power to be provided to the electric battery arrangement 906. The third power converter 706 may be configured to convert AC power from the rotary transformer 10Oa-b to DC power to be provided to the rotor 810 of an electric rotating machine 800 and / or configured to convert DC power from the rotor 810 of an electric rotating machine 800 to AC power to be provided to rotary transformer 10Oa-b. For some embodiments, it may be defined that the rotary transformer 100a-b additionally is configured to transfer electrical signals from the rotor 810 of the electric rotating machine 800. As illustrated in figure 1 , the rotary transformer 10Oa-b may be connectable, or connected, to the AC sides of the second and third second power converters 704, 706.

[0085] With reference to figure 2, aspects of embodiments of the rotary transformer 100a for the transfer of electrical signals to a rotor 810 of an electric rotating machine 800 according to the first aspect of the invention are schematically illustrated. The rotary transformer 100a may also be referred to as a rotatory, rotating, or rotatable transformer. The rotary transformer 100a includes a stationary unit 102 and a rotatable unit 104. The rotatable unit 104 is rotatable about an axis of rotation 105 in relation to the stationary unit 102. For some embodiments, the stationary unit 102 may be referred to as a stationary part, or a stator part. For some embodiments, the rotatable unit 104 may be referred to as a rotatable part, or rotor part.

[0086] With reference to figures 2, 5, 6A-C, 7 and 8, the stationary unit 102 includes a first core part 106a. The first core part 106a includes, or forms, a first compartment 130 holding one or more primary windings 108 of the rotary transformer 100a. The rotatable unit 104 includes a second core part 1 10a. The second core part 1 10a includes, or forms, a second compartment 1 18 holding one or more secondary windings 1 12 of the rotary transformer 100a. The first core part 106a is annular and configured to surround the axis of rotation 105. It may be defined that the first core part 106a is circular. The second core part 1 10a is annular and configured to surround and to rotate about the axis of rotation 105. It may be defined that the second core part 1 10a is circular. For some embodiments, it may be defined that that the stationary unit 102 comprises the one or more primary windings 108 of the rotary transformer 100a. For some embodiments, it may be defined that the rotatable unit 104 comprises the one or more secondary windings 1 12 of the rotary transformer 100a.

[0087] With reference to figures and 2 and 7, the first core part 106a and the second core part 1 10a form, or have, a gap 140, such as an air gap, between one another. For some embodiments, it may be defined that the first core part 106a is spaced (apart) from the second core part 1 10a to form a gap 140, such as an air gap, between the first core part 106a and the second core part 1 10a. For some embodiments, it may be defined that the stationary unit 102 is spaced (apart) from the rotatable unit 104 to form a gap 140, such as an air gap, between the stationary unit 102 and the rotatable unit 104.

[0088] For some embodiments, it may be defined that the rotatable unit 104 is attachable, directly or indirectly, to the rotor 810 of the electric rotating machine 800 (see figure 12). With reference to figures 2 and 5 to 7, for some embodiments, the first core part 106a may comprise, or be referred to as, a first core half, or a first half of a cup core. For some embodiments, the second core part 1 10a may comprise, or be referred to as, a second core half, or a second half of a cup core.

[0089] With reference to figures 2, 6A-C and 7, for some embodiments, it may be defined that the second core part 1 10a has a first side 114 facing the first core part 106a and that the second core part 110a has one or more second sides 116 facing away from the first core part 106a. For some embodiments, at the first side 114 of the second core part 1 10a, the second core part 1 10a may comprise, or form, the compartment 1 18 holding one or more secondary windings 1 12.

[0090] With reference to figures 2, 6A-C and 7, for some embodiments, it may be defined that the first core part 106a has a first side 132 facing the second core part 1 10a and that the first core part 106a has one or more second sides 134 facing away from the second core part 110a. For some embodiments, at the first side 132 of the first core part 106a, the first core part 106a may comprise, or form, the compartment 130 holding one or more primary windings 108.

[0091] With reference to figures 6C and 8, for some embodiments, the compartment 1 18 of the second core part 110a may be annular. For some embodiments, the compartment 130 of the first core part 106a may be annular.

[0092] With reference to figures 2 to 8, one or more of the first and second core parts 106a, 1 10a may be made of a ferromagnetic or ferrimagnetic material, for example of any sort mentioned above. However, other materials are possible. For some embodiments, one or more of the first and second core parts 106a, 1 10a may be made of a material comprising or consisting of a ferromagnetic metal or a ferromagnetic metal alloy, for example of any sort mentioned above. However, other materials are possible.

[0093] With refence to figures 6A, for some embodiments, the outer radius r1 of the second core part 110a may be equal to the outer radius r1 of the first core part 106a. For some embodiments, the inner radius r2 of the second core part 110a may be equal to the inner radius r2 of the first core part 106a. Although figures 6A-C illustrate first second core parts 106a, 1 10a substantially having the same shape, it is to be understood that for some embodiments, the shape of the first core part 106a may differ from the shape of the second core part 1 10a.

[0094] With reference to figure 3, another embodiment of the rotary transformer 100b for the transfer of electrical signals to a rotor 810 of an electric rotating machine 800 according to the first aspect of the invention is schematically illustrated. The stationary unit 102 of the rotary transformer 100b may be described to be positioned between the rotatable unit 104 and the axis of rotation 105. The stationary unit 102 of the rotary transformer 100b may be described to be positioned inside the rotatable unit 104. For some embodiments, the first core part 106b of the stationary unit 102 may be described to be positioned between the second core part 110b of the rotatable unit 104 and the axis of rotation 105. The first core part 106b of the stationary unit 102 may be described to be positioned inside the second core part 1 10b of the rotatable unit 104. The rotary transformer 100b in figure 3 may be described to be located inside a rotor shaft 840 of the rotor 810 of an electric rotating machine 800. The rotary transformer 100a in figure 2 may be described to be located outside the rotor shaft 840 of the rotor 810 of an electric rotating machine 800.

[0095] With reference to figure 5, schematic cross-section views of alternative structures of the stationary unit 102 (and / or of the first core part 106a) and the rotatable unit 104 (and / or of the second core part 110a) of embodiments of the rotary transformer according to the first aspect of the invention are illustrated in the illustrations a), b), c), d), e) and f). Each one of the stationary unit 102 and rotatable unit 104 may have windings and / or copper areas 108, 1 12, 1 13. Some embodiments may be provided with one or more polymer layers / coatings 1 15 or polymer composite layers / coatings 1 15. For additional embodiments, the core parts of the stationary unit 102 and of the rotatable unit 104 of each one of the illustrations a), b), c), d), e) and f) may interchanged.

[0096] With reference to figure 7, the rotary transformer 100a includes an inlet 142 for a cooling fluid so as to cool one or more of the stationary unit 102 and rotatable unit 104. The cooling fluid may comprise or consist of one or more of the group of: a liquid; a gas; and a gas mixture. The liquid may comprise or consist of an oil or an oil mixture. Thus, the cooling fluid may be an oil or an oil mixture. The rotary transformer 100a includes an outlet 144 for the cooling fluid.

[0097] With reference to figures 6A, 6C and 7, one 106a of the first and second core parts 106a, 1 10a comprises a first conduit 146 for guiding the cooling fluid to one 130 of the first and second compartments 130, 1 18. The first conduit 146 is connected, such as fluidly connected, to the inlet 142 of the rotary transformer 100a. For some embodiments, the first conduit 146 may be in the form of a through-hole, a hollow, such as a longitudinal hollow, formed by the one 106a of the first and second core parts 106a, 1 10a. With reference to figure 6A, 6C and 7, for some embodiments, the first core part 106a may include the first conduit 146 for guiding the cooling fluid to the first compartment 130. However, for other embodiments, the second core part 1 10a may include the first conduit 146 for guiding the cooling fluid to the second compartment 1 18. For some embodiments, the first conduit 146 may be configured to guide the cooling fluid to the first compartment 130 for cooling one or more of the first core part 106a and primary winding 108. However, for other embodiments, the first conduit 146 may be configured to guide the cooling fluid to the second compartment 1 18 for cooling one or more of the second core part 110a and secondary winding 108.

[0098] With reference to figure 7, for alternative embodiments, the first conduit 146 may also be connected to the outlet 144 of the rotary transformer 100a.

[0099] With reference to figures 7 to 10, for some embodiments, the first conduit 146 may be configured to guide, or route, one or more electrical connections 148 (see figure 10) for one or more of the primary and secondary windings 108, 1 12. The electrical connection 148 may comprise a conductor, a cable, a wire, and / or a winding end. For some embodiments, it may be defined that the rotary transformer 100a comprises one or more electrical connections 148 for one or more of the primary and secondary windings 108, 1 12 and that at least one or more portions of the one or more electrical connections 148 is / are positioned in the first conduit 146.

[0100] With reference to figures 6C to 10, for some embodiments, it may be defined that the first conduit 146 has a first mouth 154 opening to one of the first and second compartments 130, 1 18. In one 130 of the first and second compartments 130, 1 18, a first space 156 (see figures 9A and 10) may be formed between one or more conductors 160, 162 of one or more of the primary and secondary windings 108, 1 12 at the first mouth 154 of the first conduit 146 so as to let in (and / or provide an inlet path for) cooling fluid into one of the first and second compartments 130, 1 18 from the first conduit 146 via the first mouth 154 of the first conduit 146.

[0101] With reference to figures 9A and 10, for some embodiments, in one 130 of the first and second compartments 130, 1 18, one or more second spaces 158 may be formed between one or more conductors 160, 162 of one or more of the primary and secondary windings 108, 112 for the guidance of the cooling fluid in one 130 or more of the first and second compartments 130, 1 18.

[0102] With reference to figures 6A, 6C and 7, for some embodiments, one of the first and second core parts 106a, 110a may include a second conduit 150 for guiding the cooling fluid away from one 130 of the first and second compartments 130, 1 18. The second conduit 150 is connected to the outlet 144 of the rotary transformer 100a.

[0103] With reference to figures 6A, 6C and 7, for some embodiments, the first core part 106a may include the second conduit 150 for guiding the cooling fluid away from the first compartment 130. However, for other embodiments, the second core part 1 10a may include the second conduit 150 for guiding the cooling fluid away from the second compartment 1 18. For some embodiments, the first conduit 146 and the second conduit 150 may be located on opposite sides, for example on diametrically opposite sides, of the first core part 106a, or on opposite sides, for example on diametrically opposite sides, of the second core part 110a. Thus, the first conduit 146 may be remote from the second conduit 150. For some embodiments, the second conduit 150 may be adjacent to, or in the proximity of, the first conduit 146.

[0104] With reference to figures 9A and 10, for some embodiments, the second conduit 150 may be configured to guide, or route, one or more electrical connections 152 (see figure 10) for one or more of the primary and secondary windings 108, 1 12. For some embodiments, it may be defined that the rotary transformer 100a includes one or more electrical connections 152 for one or more of the primary and secondary windings 108, 1 12 and that at least one or more portions of the one or more electrical connections 152 is / are positioned in the second conduit 150.

[0105] With reference to figures 6C to 10, for some embodiments, it may be defined that the second conduit 150 has a first mouth 164 opening to one of the first and second compartments 130, 1 18. In one 130 of the first and second compartments 130, 1 18 a third space 166 (see figures 9A and 10) may be formed between one or more conductors 160, 162 of one or more of the primary and secondary windings 108, 1 12 at the first mouth 164 of the second conduit 150 so as to let out (and / or provide an outlet path for) cooling fluid from one of the first and second compartments 130, 1 18 to the second conduit 150 via the first mouth 164 of the second conduit 150.

[0106] With reference to figures 6A, 6C and 7, for some embodiments, when the first conduit 146 has a first mouth 154 opening to one 130 of the first and second compartments 130, 1 18, the first conduit 146 may have a second mouth 192 at the second side 134, 1 16 of one 106a of the first and second core part 106a, 1 10a. For some embodiments, when the second conduit 150 has a first mouth 164 opening to one 130 of the first and second compartments 130, 1 18, the second conduit 150 may have a second mouth 194 at the second side 134, 116 of one 106a of the first and second core part 106a, 1 10a.

[0107] With reference to figures 6C, 8, 9A and 10, for some embodiments, the first compartment 130 may be annular, and the second compartment 1 18 may be annular. It may be defined that the first conduit 146 has a first mouth 154 opening to one of the first and second compartments 130, 1 18. With reference to figures 8 and 10, one 102 of the stationary unit 102 and rotatable unit 104 may include a curved partition 168 (or a guide, or a wall) positioned in one 130 of the first and second compartments 130, 1 18. The curved partition 168 and walls 172, 174 of one 130 of the first and second compartments 130, 1 18 may form a curved channel 176 for guiding the cooling fluid from the first mouth 154 of the first conduit 146 and about the axis of rotation 105.

[0108] With reference to figures 8 and 10, for some embodiments, the curved channel 176 may include two or more annular paths 178, 180 for the cooling fluid. For some embodiments, it may be defined that the curved partition 168 and walls 172, 174 of one of the first and second compartments 130, 118 form two or more annular paths 178, 180 of the curved channel 176. Two or more annular paths 178, 180 extend around the axis of rotation 105. One 178 of the two or more annular paths 178, 180 is radially inside another one 180 of the two or more annular paths 178, 180. The curved channel 176 may be configured to guide the cooling fluid from said one 178 of the two or more annular paths 178, 180 being radially inside another one 180 of the two or more annular paths 178, 180 to said other one 180 of the two or more annular paths 178, 180 being radially outside one 178 of the two or more annular paths 178, 180, for example upon rotation of the rotatable unit 104. For some embodiments, the curved channel 176 may be described, or defined, as a semi-spiral-formed channel.

[0109] With reference to figures 8 and 10, for some embodiments, said one 178 of the two or more annular paths 178, 180 being radially inside another one 180 of the two or more annular paths 178, 180 may include the first mouth 154 of the first conduit 146.

[0110] With reference to figures 7, 8, 9A and 10, for some embodiments, it may be defined that the second conduit 150 has a first mouth 164 opening to one of the first and second compartments 130, 1 18. For some embodiments said other one 180 of the two or more annular paths 178, 180 being radially outside one 178 of the two or more annular paths 178, 180 may include the first mouth 164 of the second conduit 150. The curved channel 176 may be configured to guide the cooling fluid from the first mouth 154 of the first conduit 146 to the first mouth 164 of the second conduit 150, for example upon rotation of the rotatable unit 104.

[0111] With reference to figure 8, for some embodiments, it may be defined that the curved channel 176 has a first end region 182 and a second end region 184. It may be defined that the curved channel 176 has an elongated extension extending around the axis of rotation 105 from the first end region 182 of the curved channel 176 to the second end region 184 of the curved channel 176. The first end region 182 of the curved channel 176 may include the first mouth 154 of the first conduit 146. The curved channel 176 may be configured to guide the cooling fluid from the first end region 182 of the curved channel 176 to the second end region 184 of the curved channel 176, for example upon rotation of the rotatable unit 104. For some embodiments, the second end region 184 of the curved channel 176 may include the first mouth 164 of the second conduit 150. For some embodiments, said one 178 of the two or more annular paths 178, 180 being radially inside another one 180 of the two or more annular paths 178, 180 may include the first end region 182 of the curved channel 176. For some embodiments, said other one 180 of the two or more annular paths 178, 180 being radially outside one 178 of the two or more annular paths 178, 180 may include the second end region 184 of the curved channel 176. In figure 8, two annular paths 178, 180 are illustrated. However, for other embodiments, the curved channel 176 may include three or more annular paths for the cooling fluid.

[0112] With reference to figure 7, for some embodiments, the rotary transformer 100a may include a casing 196 housing the stationary unit 102 and the rotatable unit 104.

[0113] With reference to figure 7, for some embodiments, the rotary transformer 100a may include a cooling fluid system 224 for the cooling of one or more of the stationary unit 102 and rotatable unit 104. The cooling fluid system 224 may comprise one or more of the group of:

[0114] • the first chamber 130;

[0115] • the second chamber 1 18;

[0116] • the inlet 142;

[0117] • the outlet 144;

[0118] • the first conduit 146;

[0119] • the second conduit 150;

[0120] • the first space 156;

[0121] • the second space 158;

[0122] • the third space 166;

[0123] • the curved channel 176;

[0124] • the two or more annular paths 178, 180; and

[0125] • the casing 196.

[0126] It is to be understood that for some embodiments, the cooling fluid system 224 may include additional equipment, features and / or apparatuses. Another embodiment of the cooling fluid system 824 is discloses in connection with figures 12 and 13 hereinbelow. The two cooling fluid systems 224, 824 may be combined with one another.

[0127] With reference to figure 7, for some embodiments, one 102 of the stationary unit 102 and rotatable unit 104 may include a cover 186 covering one 130 of the first and second compartments 130, 1 18. One 108 or more of the primary and secondary windings 108, 1 12 may be enclosed by the cover 186 and by one of the first and second core parts 106a, 1 10a. For some embodiments, the curved partition 168 may be attached to the cover 186.

[0128] With reference to figure 7, for some embodiments, the curved partition 168 may be integrally formed with the cover 186. However, for other embodiments, the curved partition 168 may be attached to the cover 186 by way of other means of attachment. The fact that the curved partition 168 is integrally formed with the cover 186 implies, or means, that curved partition 168 and the cover 186 are formed into a single piece and / or are formed from a single piece. For example a piece of material may be formed into the cover 186 and the curved partition 168 integrally formed therewith, for example by way moulding, or casting. Expressed alternatively, the fact that the curved partition 168 is integrally formed with the cover 186 may imply, or may mean, that the curved partition 168 and the cover 186 are made of a single piece.

[0129] With reference to figure 7, for some embodiments, one or more of the cover 186 and curved partition 168 may be made of a material comprising or consisting of a polymer or a polymer composite. For some embodiments, the first compartment 130 may open in a direction toward the second core part 1 10a while the second compartment 118 may open in a direction toward the first core part 106a.

[0130] With reference to figures 1 1 to 13, an embodiment of the electric rotating machine 800 according to the second aspect of the invention is schematically illustrated. The electric rotating machine 800 may act, or function, as an electric motor 804, for example for propelling a vehicle 900 (for example, see figure 14), such as an electric vehicle, EV, and / or as an electric generator 804, for example, for charging one or more electric battery arrangements 906 (see figure 14) and / or one or more electric battery packs.

[0131] With reference to figure 12, the electric rotating machine 800 includes a stator 806 and a rotor 810 rotatable about an axis of rotation 812 in relation to the stator 806. The electric rotating machine 800 includes a rotary transformer 100a according to any one of the embodiments disclosed above or below. The stator 806 may include one or more stator windings 808. It may be defined that the stator 806 is spaced from the rotor 810 to form a gap 814 between the stator 806 and the rotor 810, such as an annular gap 814. The rotor 810 may include one or more rotor windings (not shown in figure 12). However, for alternative embodiments, the electric rotating machine 800 may be configured for and operate according to other electrical operation schemes for electric rotating machines. For example, for alternative embodiments, the rotor may include one or more permanent magnets. Thus, the electric rotating machine may be a permanent magnet, PM, machine. Various conventional electric rotating machines and various conventional electrical operation schemes for conventional electric rotating machines are known to the skilled person and are thus not discussed herein in further detail.

[0132] With reference to figure 12, the electric rotating machine 800 may include a rotor compartment 816 holding the rotor 810. The electric rotating machine 800 may include a housing 818 which houses the stator 806 and the rotor 810. The housing 818 may define, or form, the rotor compartment 816. For some embodiments, the electric rotating machine 800 includes one or more gable units 820, 822 immovable in relation to the stator 806. For example, the rotor 810 may be connected, or attached, to the one or more gable units 820, 822 via one or more bearings 823.

[0133] With reference to figure 12, and as stated above, the electric rotating machine 800 includes a rotary transformer 100a according to any one of the embodiments disclosed above or below. The rotatable unit 104 of the rotary transformer 100a is positioned between the stationary unit 102 and the gable unit 820 to the right in figure 12. The stationary unit 102 of the rotary transformer 100a is positioned between the rotatable unit 104 and the gable unit 822 to the left in figure 1 2. However, it is to be understood that different embodiments of the rotary transformer may applied to the electric rotating machine 800 in several other ways and at other positions than what is illustrated in figure 12.

[0134] With reference to figure 13, for some embodiments, the electric rotating machine 800 may include a cooling fluid system 824 for cooling one or more of the rotor 810 and stator 806. For some embodiments, the rotary transformer 100a may comprise, or be equipped with, a cooling fluid system 824 for cooling one or more of one or more of the stationary unit 102 and rotatable unit 104 of the rotary transformer 100a. As also stated above, the cooling fluid of the cooling fluid system 824 may comprise or consist of one or more of the group of: a liquid; a gas; and a gas mixture. The liquid may comprise or consist of an oil or an oil mixture. Thus, a cooling fluid of the cooling fluid system 824 may be an oil or an oil mixture. The cooling fluid system 824 may be configured to cool one or more of the rotor 810, stator 806, stationary unit 102 and rotatable unit 104.

[0135] With reference to figure 12, for some embodiments, the cooling fluid system 824 may include one or more channels 826 for guiding a cooling fluid, for example to and from the stator 806 and / or the rotor 810. The housing 818 may include, or form, the one or more channels 826. The cooling fluid system 824 may include an inlet 828 for the inlet of cooling fluid and an outlet 830 for the outlet of cooling fluid. The inlet 828 and the outlet 830 may be an inlet 828 and outlet 830 of the housing 818. The inlet 828 may be an inlet 828 for the inlet of cooling fluid to the one or more channels 826. The outlet 830 may be an outlet 830 for the outlet of cooling fluid from the one or more channels 826.

[0136] With reference to figure 13, the cooling fluid system 824 may include one or more conduits 832, or lines, for guiding a cooling fluid, for example to or from the one or more channels 826 and / or the housing 818 of the electric rotating machine 800. The cooling fluid system 824 may include a cooling fluid collector and provider 834, for example a fluid-collecting tray or vessel, or a fluid sump. For some embodiments, the cooling fluid collector and provider 834 may be fluidly connected to the one or more channels 826 via a heat exchanger 836.

[0137] With reference to figure 14, an embodiment of the vehicle 900 according to the third aspect of the invention is schematically illustrated. The vehicle 900 includes one or more of the group of: a rotary transformer 100a-b according to any one of the embodiments disclosed above or below; and an electric rotating machine 800 according to any one of the embodiments disclosed above or below. The one or more electric rotating machines 800 may comprise one or more electric motors 802 and / or one or more electric generators 802. For example, the one or more electric rotating machines 800 may be configured for the propulsion of the vehicle 900. For example, one or more electric rotating machines 800 may be configured for charging one or more electrical battery arrangements 906 and / or one or more electric battery packs 910 of the vehicle 900. However, the electric rotating machine 800 may be used for other applications.

[0138] With reference to figure 14, the vehicle 900 is illustrated as a tractor vehicle. However, in other embodiments, the vehicle 900 may, for example, be a bus, a truck, a heavy truck or a car. Other types of vehicles are also possible. The vehicle 900 may be an electric vehicle, EV, for example a hybrid vehicle or a hybrid electric vehicle, HEV, or a battery electric vehicle, BEV.

[0139] With reference to figure 14, the vehicle 900 may be a wheeled vehicle, i.e. a vehicle 900 having wheels 902. Only the wheels 902 on the left-hand side of the vehicle 900 are visible in figure 14. It is to be understood that the vehicle 900 may have fewer or more wheels than what is shown in figure 14. The vehicle 900 may comprise a powertrain 904, for example configured for one of an EV, HEV and BEV. The vehicle 900 may be configured to hold or carry, or may include, one or more electrical battery arrangements 906 including two or more electric battery cells 908. The vehicle 900 may be configured to hold or carry, or may include, one or more electric battery packs 910 including two or more electric battery cells 908 and / or including two or more electrical battery arrangements 906, which may be referred to as modules. The electrical battery arrangement 906 and / or the electric battery pack 910 may, for example, be attachable to a chassis 912 of the vehicle 900. It is to be understood that the vehicle 900 may include further unites, components, such as electrical and / or mechanical components, a combustion engine 914 and other devices required for a vehicle 900, such as for an EV, HEV or BEV.

[0140] With reference to figure 14, it may be defined that the powertrain 904 and / or the one or more electric rotating machines 800 is / are configured to propel, or drive, the vehicle 900. It may be defined that the powertrain 904 includes the electrical battery arrangement 906 and / or the electric battery pack 910. The one or more electric rotating machines 800 may be located at locations different from what is illustrated in figure 14, for example in connection with the combustion engine 914, for example acting as an electric generator. With reference to figure 14, the vehicle 900 may include a vehicle electrical system 916. It may be defined that the vehicle electrical system 916 is configured for direct current. It may be defined that vehicle electrical system 916 is a vehicle high voltage system 916. It may be defined that the vehicle high voltage system 916 is configured for a high voltage, such as a voltage above 60 V, for example above 400 V, or above 450 V, such as above 650 V. For example, the vehicle high voltage system 916 may be configured for a voltage up to 1500 V and / or for a voltage above 1500 V. The electric power, or the electric current, for example the direct current, of the vehicle electrical system 916 may be transferred at a high voltage, for example at one or more of the voltages levels mentioned above. The vehicle electrical system 916 may be configured to transfer the electric power, or the electric current, at a high voltage, for example at one or more of the voltages levels mentioned above. The vehicle electrical system 916 may be configured to transfer direct current.

[0141] With reference to Figure 14, the vehicle electrical system 916 may be electrically connected, or connectable, to one or more electrical battery arrangements 906 and / or one or more electric battery packs 910. It may be defined that the electrical battery arrangement 906 and / or the electric battery pack 910 is / are configured for high voltage, for example for one or more of the voltages levels mentioned above. The vehicle electrical system 916 may be configured to electrically connect the electrical battery arrangement 906 and / or the electric battery pack 910 to the powertrain 904 of the vehicle 900. The vehicle electrical system 916 may be configured to electrically connect the electrical battery arrangement 906 and / or the electric battery pack 910 to the one or more electric rotating machines 800 of the vehicle 900. It may be defined that the vehicle electrical system 916 is configured to transfer the electric power, or the electric current, for example between the one or more electric rotating machines 800 (and / or the powertrain 904) and the electrical battery arrangement 906 and / or the electric battery pack 910.

[0142] It is to be understood that embodiments of the rotary transformer 100a-b and the electric rotating machine 800 may be applied to configurations, structures, or apparatuses different from a vehicle 900, for example for charging electric batteries not located in a vehicle, or for a wind turbine generator (WTG) including an electric generator etc. When an item is disclosed to be connected to another item in this disclosure, in general it implies that the two items are fluidly, electrically and / or mechanically connected to one another.

[0143] The present invention is not limited to the above-described embodiments. Instead, the present invention relates to, and encompasses all different embodiments being included within the scope of the independent claims.

Claims

Claims1. A rotary transformer (100a-b) for the transfer of electrical signals to a rotor (802) of an electric rotating machine (800), wherein the rotary transformer (100a-b) comprises a stationary unit (102), and a rotatable unit (104) rotatable about an axis of rotation (105) in relation to the stationary unit (102), wherein the stationary unit (102) comprises a first core part (106a-b) comprising a first compartment (130) holding one or more primary windings (108) of the rotary transformer (100a-b), wherein the rotatable unit (104) comprises a second core part (1 10a-b) comprising a second compartment (1 18) holding one or more secondary windings (1 12) of the rotary transformer (1 OOa-b), wherein the first core part (106a-b) is annular and configured to surround the axis of rotation (105), wherein the second core part (1 10a-b) is annular and configured to surround and to rotate about the axis of rotation (105), wherein the first core part (106a-b) and the second core part (1 10a-b) form a gap (140) between one another, wherein the rotary transformer (1 OOa-b) comprises an inlet (142) for a cooling fluid so as to cool one or more of the stationary unit (102) and rotatable unit (104), wherein the rotary transformer (1 OOa-b) comprises an outlet (144) for the cooling fluid, wherein one of the first and second core parts (106a-b, 1 10a-b) comprises a first conduit (146) for guiding the cooling fluid to one of the first and second compartments (130, 1 18), and wherein the first conduit (146) is connected to the inlet (142) of the rotary transformer (1 OOa-b).

2. A rotary transformer (1 OOa-b) according to claim 1 , wherein the first core part (106a-b) comprises the first conduit (146) for guiding the cooling fluid to the first compartment (130).

3. A rotary transformer (100a-b) according to claim 2, wherein the first conduit (146) is configured to guide the cooling fluid to the first compartment (130) for cooling one or more of the first core part (106a-b) and primary winding (108).

4. A rotary transformer (100a-b) according to any one of the claims 1 to 3, wherein the first conduit (146) is connected to the outlet (144) of the rotary transformer (100a-b).

5. A rotary transformer (100a-b) according to any one of the claims 1 to 4, wherein the first conduit (146) is further configured to guide one or more electrical connections (148) for one or more of the primary and secondary windings (108, 1 12).

6. A rotary transformer (100a-b) according to any one of the claims 1 to 5, wherein the rotary transformer (100a-b) comprises one or more electrical connections (148) for one or more of the primary and secondary windings (108, 1 12), and wherein at least one or more portions of the one or more electrical connections (148) is / are positioned in the first conduit (146).

7. A rotary transformer (100a-b) according to any one of the claims 1 to 6, wherein one of the first and second core parts (106a-b, 1 10a-b) comprises a second conduit (150) for guiding the cooling fluid away from one of the first and second compartments (130, 1 18), and wherein the second conduit (150) is connected to the outlet (144) of the rotary transformer (100a-b).

8. A rotary transformer (100a-b) according to any one of the claims 1 to 7, wherein the first compartment (130) is annular, wherein the second compartment (1 18) is annular, wherein the first conduit (146) has a first mouth (154) opening to one of the first and second compartments (130, 1 18),wherein one of the stationary unit (102) and rotatable unit (104) comprises a curved partition (168) positioned in one of the first and second compartments (130, 1 18), and wherein the curved partition (168) and walls (172, 174) of one of the first and second compartments (130, 1 18) form a curved channel (176) for guiding the cooling fluid from the first mouth (154) of the first conduit (146) and about the axis of rotation (105).

9. A rotary transformer (1 OOa-b) according to claim 8, wherein the curved channel (176) comprises two or more annular paths (178, 180) for the cooling fluid, wherein the two or more annular paths (178, 180) extend around the axis of rotation (105), wherein one (178) of the two or more annular paths (178, 180) is radially inside another one (180) of the two or more annular paths (178, 180), and wherein the curved channel (176) is configured to guide the cooling fluid from said one (178) of the two or more annular paths (178, 180) being radially inside another one (180) of the two or more annular paths (178, 180) to said other one (180) of the two or more annular paths (178, 180) being radially outside one (178) of the two or more annular paths (178, 180).

10. A rotary transformer (1 OOa-b) according to any one of the claims 1 to 9, wherein one of the stationary unit (102) and rotatable unit (104) comprises a cover (186) covering one of the first and second compartments (130, 1 18), and wherein one or more of the primary and secondary windings (108, 1 12) is enclosed by the cover (186) and one of the first and second core parts (106a-b, 1 10a- b).1 1. A rotary transformer (1 OOa-b) according to claim 10, wherein the curved partition (168) is attached to the cover (186).

12. A rotary transformer (1 OOa-b) according to claim 10 or 1 1 , wherein one or more of the cover (186) and curved partition (168) is / are made of a material comprising or consisting of a polymer or a polymer composite.

13. A rotary transformer (100a-b) according to any one of the claims 1 to 12, wherein the rotary transformer (100a-b) comprises a cooling fluid system (200) for the cooling of one or more of the stationary unit (102) and rotatable unit (104), and wherein the cooling fluid system (200) comprises one or more of the group of:• the first chamber (130);• the second chamber (118);• the inlet (142);• the outlet (144);• the first conduit (146);• the second conduit (150);• the first space (156);• the second space (158);• the third space (166);• the curved channel (176);• the two or more annular paths (178, 180); and• the casing (196).

14. An electric rotating machine (800) comprising a stator (), a rotor () rotatable about an axis of rotation () in relation to the stator (), and a rotary transformer (1 OOa-b) according to any one of the claims 1 to 13.

15. A vehicle (900) comprising one or more of the group of:• a rotary transformer (1 OOa-b) according to any one of the claims 1 to 13; and• an electric rotating machine (800) according to claim 14.

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