Transformer for vehicle-mounted charger of electric vehicle

Abstract

The present invention relates to a transformer for an on-board charger of an electric vehicle, comprising: a flat primary coil for receiving a current of a charger of an electric vehicle; a lower secondary coil element which is provided in close contact with the lower surface of the primary coil (110, 120, 130, 140) below the primary coil (110, 120, 130, 140), generates an induced current by the current flowing through the primary coil (110, 120, 130, 140), and outputs the induced current to a high-voltage battery; and an upper secondary coil element (220) which is provided in close contact with the upper surface of the primary coils (110, 120, 130, 140) above the primary coils (110, 120, 130, 140), generates an induced current by means of the current flowing through the primary coils (110, 120, 130, 140), and outputs the induced current to the high-voltage battery, whereby the size and height can be reduced.

Description

Technical Field

[0001] The invention relates to an on-board charger (On Board Charger) of an electric vehicle. Background Art

[0002] Plug in Hybrid electric vehicle (PHEV) and electric vehicle (EV) (hereinafter collectively referred to as electric vehicles) require a charging device that can charge the high voltage battery that drives the vehicle motor with 200V alternating current (AC). This charging device is called an on-board charger.

[0003] An electric vehicle includes an on-board charger for charging a high-voltage battery that drives a vehicle motor with common electricity (200V AC) supplied by the charger; a high-voltage battery for charging the electricity converted by the on-board charger; and a low-voltage DC-DC converter (LDC) that supplies power to the electrical components of the vehicle by converting the high voltage of the high-voltage battery into a low voltage of 12V.

[0004] Furthermore, the on-board charger built into the electric vehicle includes: a first converter, which performs full-wave rectification on the 220V AC power supplied from the charger through a bridge diode, and boosts the full-wave rectified voltage through a boost converter circuit; a second converter, which converts the rectified voltage output from the first converter into a high-frequency AC voltage through a full-bridge circuit; a transformer, which is used to convert the high-frequency AC voltage output from the second converter into a higher voltage and physically insulate the 220V AC power from the high-voltage battery; a rectifier, which rectifies and filters the high-frequency high-voltage AC voltage converted by the transformer, and converts it into a direct current (DC) voltage and supplies it to the high-voltage battery.

[0005] Here, the structure of a conventional on-vehicle charger transformer will be described.

[0006] In a conventional on-vehicle charger transformer, a primary coil is wound around a special bobbin, and an insulating tape is wound around the wound primary coil for insulation.

[0007] Then, after the insulating tape is wound around the primary coil, the secondary coil is wound around it.

[0008] Then, after the secondary coil is wound, an insulating tape is wound again for insulation.

[0009] Furthermore, when the secondary coil is wound three times, an insulating tape is wound in the middle of the secondary coil each time the secondary coil is wound to insulate it.

[0010] However, the on-board charger transformer for electric vehicles according to the above-mentioned prior art has the following problems.

[0011] First, the transformer product size is very large. Since the secondary coil is wound coaxially with the primary coil wound on the bobbin, there is a problem that the product size becomes larger, which leads to the problem that the overall size of the car charger becomes larger.

[0012] Secondly, since the assembly process of winding the primary coil, winding the insulating tape to insulate it, and then winding the secondary coil on the insulating tape and winding the insulating tape again is repeated, the number of assembly processes increases, which leads to a problem of reduced productivity.

[0013] Third, since the winding of the primary coil and the secondary coil is performed manually, the coil windings are not aligned, resulting in increased loss and deterioration of anti-electromagnetic interference (EMI) performance. Summary of the invention

[0014] Technical problem to be solved by the invention

[0015] The present invention is proposed to solve the above-mentioned problems of the prior art. The object of the present invention is to provide a transformer for an on-board charger of an electric vehicle as follows:

[0016] First, the transformer for the on-board charger can maintain insulation even at high voltages from several kV to tens of kV.

[0017] Second, ensure the winding uniformity and alignment between the primary and secondary coils to improve efficiency and anti-electromagnetic interference characteristics.

[0018] Third, by increasing the cross-sectional area and surface area to improve the epidermal effect, heat generation can be reduced.

[0019] Fourth, by simplifying the operation process, processing costs can be reduced.

[0020] Fifth, the height can be lowered and the size can be reduced, which can reduce the occupied space in electric vehicles and improve product competitiveness,

[0021] Sixth, the loss between the primary and secondary coils can be reduced, thereby improving efficiency.

[0022] Seventh, even with a small size, it can supply large current and high voltage.

[0023] Eighth, it can improve the adhesion of the primary coil.

[0024] Ninth, the number of coil assembly processes can be reduced, thereby improving productivity and price competitiveness.

[0025] Tenth, the primary coil and secondary coil components can be assembled easily, conveniently and accurately, and there is no need to perform terminal alignment (wiring) work (wiring work) for the primary side coil and the secondary side coil separately.

[0026] Eleventh, the wiring between the transformer and other components in the on-board charger can be easily and conveniently performed.

[0027] Twelfth, by using flat copper wire to standardize the alignment of the coils, uniformity of quality can be achieved.

[0028] Thirteenth, even unskilled workers can quickly and accurately perform wiring work on the transformer for the on-board charger without making wiring errors.

[0029] Technical solutions to the problem

[0030] In order to achieve the above object, the on-board charger transformer of the electric vehicle of the present invention is used as a common AC power (220V) supplied from the charger of the electric vehicle. An on-board charger for an electric vehicle for charging a high-voltage battery of the electric vehicle using an AC power supply, characterized in that it comprises: a flat primary coil for receiving current from a charger of the electric vehicle; a lower secondary coil element, which is arranged below the primary coil in close contact with the lower surface of the primary coil, and generates an induced current from the current flowing in the primary coil and outputs it to the high-voltage battery; and an upper secondary coil element, which is arranged above the primary coil in close contact with the upper surface of the primary coil, and generates an induced current from the current flowing in the primary coil and outputs it to the high-voltage battery, wherein the primary coil is composed of an adhesive-type coated conductor, in which a conductive wire is coated with an insulating tape, an adhesive layer is formed by coating an adhesive on the outer peripheral surface of the coated insulating tape, and after the adhesive-type coated conductor is wound multiple times to form a first central hole in the center, the coated adhesive layer is melted and solidified, so that the adhesive-type coated conductors that are wound in close contact with each other are joined to each other by welding and formed in a coil form.

[0031] Effects of the Invention

[0032] The on-board charger transformer for electric vehicles of the present invention having the above-mentioned structure has the following effects:

[0033] First, the transformer for the on-board charger can maintain insulation even at high voltages ranging from several kV to tens of kV (enhanced insulation resistance under high voltage).

[0034] Secondly, the winding uniformity and the alignment between the primary coil and the secondary coil can be ensured, thereby improving the efficiency and anti-electromagnetic interference characteristics (compared with the prior art, the characteristics are improved by more than 3 to 4 dB).

[0035] Third, the flat surface shape increases the cross-sectional area and surface area, thereby improving the epidermal effect and reducing heat generation.

[0036] Fourth, by simplifying the operation process, processing costs can be reduced.

[0037] Fifth, the height can be lowered and the size can be reduced, which can reduce the occupied space within the electric vehicle and improve product competitiveness.

[0038] Sixth, the loss between the primary side coil and the secondary side coil is reduced, thereby improving efficiency.

[0039] Seventh, even with a small size, it can supply large current and high voltage.

[0040] Eighth, the adhesion of the primary coil can be improved.

[0041] Ninth, the assembly process of the primary coil can be reduced (compared with the production process of the existing vehicle charger transformer, the assembly process is reduced by 50%), thereby improving productivity and price competitiveness.

[0042] Tenth, the assembly work of the primary coil and the secondary coil components can be performed easily, conveniently and accurately, and there is no need to perform terminal alignment (wiring) work (wiring work) for the primary side coil and the secondary side coil separately.

[0043] Eleventh, the wiring operation between the transformer and other components in the vehicle charger can be carried out easily and conveniently.

[0044] Twelfth, by standardizing the alignment of the coils using flat copper wire, uniformity of quality can be achieved.

[0045] Thirteenth, even unskilled workers can quickly and accurately perform wiring work on the transformer for the on-board charger without making wiring errors. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 FIG. 1 is a perspective view of a transformer A for an on-board charger of an electric vehicle according to an embodiment of the present invention.

[0047] Figure 2 for Figure 1 Plane exploded stereogram.

[0048] Figure 3 for Figure 1 Exploded bottom perspective view.

[0049] Figure 4 for Figure 1 A cross-sectional view and an enlarged view of the main parts are shown in the state where the mounting member 400 and the upper and lower magnetic cores 320 and 310 are removed.

[0050] Figure 5 This is a conceptual diagram of the structure of the primary coil 120 of another embodiment. Figure 5 Part (a) is a three-dimensional view and an enlarged view of the main part of the primary coil 120 of another embodiment. Figure 5 Part (b) of Figure 5 Cross-sectional view of part (a).

[0051] Figure 6 This is a conceptual diagram of the structure of the primary coil 130 of another embodiment. Figure 6 Part (a) is a three-dimensional view of the primary coil 130 of another embodiment. Figure 6 Part (b) represents Figure 6 FIG. 1 is a diagram for explaining the concept of winding of the primary coil 130 shown in part (a).

[0052] Figure 7 It is a perspective view of the primary coil 140 according to still another embodiment.

[0053] Figure 8 It is an exploded perspective view of the upper copper plate coil 221 and the lower copper plate coil 211 provided in the upper secondary coil element 220 and the lower secondary coil element 210 .

[0054] Fig. 9 It is a conceptual diagram of the cross-sectional structure of the adhesive-type covered conductive wires 110 ′, 120 ′, 130 ′ used to form the primary coils 110 , 120 , 130 .

[0055] Fig.10 FIG. 1 is a conceptual diagram of the structure of an adhesive coated conductor 140 ′ for forming a primary coil 140 of another embodiment. Fig.10 Part (a) is a schematic diagram of the appearance structure of the thin copper wire 140-1 when the conductive wire is composed of the thin copper wire 140-1. Fig.10 Part (b) is a conceptual diagram of the cross-sectional structure of the adhesive coated conductor 140'. Fig.10 Part (c) is a conceptual diagram of the appearance of an adhesive-type covered conductor 140 ′ showing a plurality of exposed thin copper wires Li.

[0056] Description of Reference Numerals

[0057] A: Transformer for an on-board charger of an electric vehicle according to an embodiment of the present invention

[0058] 110, 120, 130, 140: primary coil C1, C2, C3, C4: first central hole of primary coil

[0059] 110a, 120a, 130a: flat upper surface 110b, 120b, 130b: flat lower surface

[0060] 110', 120', 130', 140': Bonded coated conductor

[0061] 110': first adhesive coated wire 120': second adhesive coated wire

[0062] 130': 3rd adhesive coated wire 140': 4th adhesive coated wire

[0063] 110-1, 120-1, 130-1, 140-1: Conductive wire

[0064] 110-2, 120-2, 130-2, 140-2: Insulation tape

[0065] 110-3, 120-3, 130-3, 140-3: Adhesive layer

[0066] 110c: Flat left surface 110d: Flat right surface

[0067] 130L: Primary side lower coil 130H: Primary side upper coil

[0068] 141: 1st input wire section 142: 1st side winding section

[0069] 143: First output wire portion 144: First input terminal

[0070] 144a: Second input terminal fixing hole 145: First output terminal

[0071] 145a: 1st output terminal fixing hole

[0072] 210: Lower secondary coil element 210a: Lower center hole

[0073] 210b: lower surface of the lower secondary coil element 210c: upper surface of the lower secondary coil element

[0074] 211: Lower copper coil 211a, 211c: Lower terminals

[0075] 211a': lower terminal hole 211b: lower spiral part

[0076] 211d: Lower bridge 211e: Bridge groove

[0077] 212: Lower insulating portion 213: Inner protruding frame

[0078] 214: Outer protruding frame 215: Lower quasi-protruding portion

[0079] 216: Insertion plate 217: Primary terminal block

[0080] 220: Upper secondary coil element 220a: Upper center hole

[0081] 220b: lower surface of the upper secondary coil element 220c: upper surface of the upper secondary coil element

[0082] 221: Upper copper coil 221a, 221c: Upper terminal

[0083] 221a': upper terminal hole 221b: upper spiral part

[0084] 221d: Upper bridge 221e: Bridge protrusion

[0085] 222: Upper insulating portion 225: Upper quasi-protrusion

[0086] 310: Lower core 311: Midfoot of the lower core

[0087] 313: Lower placement slot 320: Upper magnetic core

[0088] 321: middle foot of upper magnetic core 323: upper placement groove

[0089] 400: Mounting part Sa: Placement space

[0090] 411: base 412: peripheral part

[0091] 412a: left side of the outer periphery 412b: right side of the outer periphery

[0092] 413: 1st pass slot 414: 2nd pass slot

[0093] 416: Insertion gap 417: Reinforcement plate

[0094] 417a: Primary terminal hole

[0095] P1: Primary side connection pin P2: Secondary side connection pin DETAILED DESCRIPTION

[0096] The preferred embodiments of the transformer for an on-board charger of an electric vehicle of the present invention will be described in detail below with reference to the accompanying drawings.

[0097] The on-board charger transformer 100 of an electric vehicle according to an embodiment of the present invention is used to convert the common AC power (220V An on-board charger for an electric vehicle for charging a high-voltage battery of the electric vehicle by AC) is characterized by comprising: a flat primary coil 110, 120, 130, 140 for receiving current from a charger of the electric vehicle; a lower secondary coil element 210, which is arranged below the primary coil 110, 120, 130, 140 and in close contact with the lower surface of the primary coil 110, 120, 130, 140, and generates an induced current through the current flowing in the primary coil 110, 120, 130, 140 and outputs it to a high-voltage battery; an upper secondary coil element 220, which is arranged above the primary coil 110, 120, 130, 140 and in close contact with the upper surface of the primary coil 110, 120, 130, 140, and generates an induced current through the current flowing in the primary coil 110, 120, 130, 140 and outputs it to a high-voltage battery.

[0098] In this case, the primary coils 110, 120, 130, 140 are composed of adhesive coated wires 110', 120', 130', 140', in which conductive wires 110-1, 120-1, 130-1, 140-1 are coated with insulating tapes 110-2, 120-2, 130-2, 140-2, and adhesive layers 110-3, 120-3, 130-3, 140-3 are formed by applying an adhesive to the outer peripheral surfaces of the coated insulating tapes 110-2, 120-2, 130-2, 140-2.

[0099] Furthermore, the primary coils 110, 120, 130, 140 are characterized in that after the adhesive coated wires 110', 120', 130', 140' are wound multiple times using a winding member (not shown) to form the first central holes C1, C2, C3, C4 in the center, the coated adhesive layers 110-3, 120-3, 130-3, 140-3 are melted using, for example, a solvent (e.g., ethanol) or are melted by heating (or hot air) and then solidified, so that the adhesive coated wires 110', 120', 130', 140' that are tightly wound together are joined to each other by welding and formed into a hard state that is aligned (there are no unevenness on the outer surface) and formed in a coil shape.

[0100] Thus, even at a high voltage of several kV to several tens of kV, the efficiency between the primary side coil and the secondary side coil can be maintained without causing insulation breakdown.

[0101] The wire winding member may utilize a winding jig or a winder.

[0102] The adhesive may consist of an adhesive coating.

[0103] The insulating tapes 110 - 2 , 120 - 2 , 130 - 2 , and 140 - 2 may be made of polyimide tapes.

[0104] Since the conductive wires 110 - 1 , 120 - 1 , 130 - 1 , and 140 - 1 are located inside the insulating tapes 110 - 2 , 120 - 2 , 130 - 2 , and 140 - 2 that function as outer skins, they can also be referred to as “conductive cores”.

[0105] As described above, the on-board charger transformer 100 of the electric vehicle according to one embodiment of the present invention is used to convert the high-frequency AC voltage output from the second converter of the on-board charger into a high voltage and to physically insulate the 220V AC power from the high-voltage battery.

[0106] The primary coils 110, 120, 130, 140 include: input wire portions 111, 121, 131, 141 connected to the charger side of the electric vehicle (specifically, the second converter of the on-board charger), formed of linear adhesive coated wires 110', 120', 130', 140'; and primary winding portions 112, 122, 132, 142 extending from the input wire portions 111 to the secondary winding portions 112. , 121, 131, 141, and the adhesive coated wires 110', 120', 130', 140' are wound in a flat shape for many times to form the first central holes C1, C2, C3, C4 in the center; the output wire parts 113, 123, 133, 143 are formed by the linear adhesive coated wires 110', 120', 130', 140', so as to be wound on the primary side wire parts 112, 123 The terminals 2, 132, and 142 are connected to the charger side of the electric vehicle, and in the primary side winding parts 112, 122, 132, and 142, the winding parts are automatically wound in a flat plate shape so that the adhesive coated wires 110', 120', 130', and 140' are closely attached to each other and aligned in the horizontal direction and / or vertical direction (that is, this is a concept including the horizontal direction and the vertical direction, or any direction in the vertical direction or the vertical direction), and then the applied adhesive layers 110-3, 120-3, 130-3, and 140-3 are melted using a solvent (for example, ethanol) or melted by heating (or hot air) and then solidified, so that the adhesive coated wires 110', 120', 130', and 140' are bonded to each other by welding and formed into a hard state in which they are aligned (there are no unevenness on the outer surface).

[0107] This has the advantage of preventing insulation breakdown even at a high voltage of several kV to several tens of kV, reducing the distance between the primary coil and the secondary coil, improving the close contact, thereby reducing losses and further improving efficiency.

[0108] On the other hand, the conductive wires 110 - 1 , 120 - 1 , 130 - 1 , and 140 - 1 may include any known conductive wires as the coating objects of the insulating tapes 110 - 2 , 120 - 2 , 130 - 2 , and 140 - 2 .

[0109] Next, the structure of the primary coils 110 , 120 , 130 , and 140 of the transformer A for the on-board charger of the electric vehicle according to an embodiment of the present invention will be described in detail.

[0110] According to an embodiment, the primary coils 110, 120, 130, 140 may be formed in a square or circular shape, for example, Figures 1 to 5 As shown, it can be formed in a square shape with square first central holes C1 and C2, as shown in FIG. Figure 6 and Figure 7 As shown, the circular shape may be formed with circular first central holes C3 and C4, and any case falls within the technical scope of the present invention.

[0111] The conductive wires 110-1, 120-1, and 130-1 of the primary coils 110, 120, and 130 are formed of flat copper wires (flat thin copper wires), and the flat copper wires (flat thin copper wires) are composed of a flat upper surface formed as a flat surface along the length direction, a flat lower surface formed as a flat surface, and a side portion between the flat upper surface and the flat lower surface.

[0112] In this case, in the primary coils 110, 120, 130, when the conductive wires 110-1, 120-1, 130-1 formed by the flat upper surface, the flat lower surface, and the side portions are covered with insulating tapes 110-2, 120-2, 130-2, and adhesive layers 110-3, 120-3, 130-3, 140-3 are formed on the outer peripheral surfaces of the covered insulating tapes 110-2, 120-2, 130-2, the conductive wires 110-1, 120-1, 130-1 are covered with insulating tapes 110-2, 120-2, 130-2, and the adhesive layers 110-3, 120-3, 130-3, 140-3 are formed on the outer peripheral surfaces of the covered insulating tapes 110-2, 120-2, 130-2. Flat surface adhesive coated conductors 110', 120', 130' are formed on the upper and lower surfaces respectively with flat upper surfaces 110a, 120a, 130a and flat lower surfaces 110b, 120b, 130b, and the flat surface primary coils 110, 120, 130 are configured to be wound multiple times using the flat adhesive coated conductors 110', 120', 130' to form first central holes C1, C2, C3 in the center.

[0113] As shown in the attached figure Figures 1 to 4As shown, the side portions 110c and 110d of the adhesive coated conductor 110' of the primary coil 110 are composed of a flat left surface 110c and a flat right surface 110d formed as flat surfaces, and the primary coil 110 is formed by winding the adhesive coated conductor 110' into a spiral shape in the horizontal direction in a manner such that the flat left surface 110c and the flat right surface 110d face each other.

[0114] That is, the primary coil 110 is wound in a spiral shape in the horizontal direction so that the left surface 110 c which is one surface of the flat side portion faces the right surface 110 d of the adjacent flat side portion.

[0115] Among them, Figures 1 to 4 As shown in FIG. 1 , the primary coil 110 in which the flat surface adhesive-type covered conductive wire 110 ′ is extended and wound in the horizontal direction is referred to as a horizontally extended flat surface primary coil 110 .

[0116] The primary coil 110 is characterized in that the flat left surface 110 c and the flat right surface 110 d are in close contact with each other and are wound in a spiral shape in the horizontal direction.

[0117] Next, still another embodiment of the primary coil will be described.

[0118] First, refer to Figure 5 An example in which the primary coil 120 is stacked in the vertical direction will be described.

[0119] like Figure 5 As shown, the width w1 of the flat surface bonding type coated conductor 120' forming the primary coil 120 is greater than its thickness t1. The primary coil 120 is characterized in that the flat surface bonding type coated conductor 120' is stacked in a vertical direction as the up-down direction so that the flat upper surface 120a and the flat lower surface 120b face each other and are formed into a spiral shape.

[0120] That is, the primary coil 120 is characterized in that the flat lower surface 120 b is located directly above the flat upper surface 120 a , and the flat lower surface 120 b is located on the flat upper surface 120 a thereon, and the flat lower surface 120 b is sequentially spirally formed in a vertical direction in this manner.

[0121] like Figure 5 The primary coil 120 in which the flat surface bonding type covered conductive wire 120 ′ is spirally shaped in the vertical direction is referred to as a vertically extended flat surface primary coil 120 .

[0122] The primary coil 120 is characterized in that the flat upper surface 120 a and the flat lower surface 120 b are in close contact with each other and are formed in a spiral shape in the up-down direction.

[0123] According to an embodiment, the primary coil 120 may be formed in a spiral shape in the up-down direction while a gap is formed between the flat upper surface 120 a and the flat lower surface 120 b .

[0124] Next, embodiments of vertical and horizontal expansion will be described.

[0125] like Figure 6 As shown, the width w of the flat surface bonding type covered conductor 130' forming the primary coil 130 is greater than its thickness t, and the primary coil 130 is characterized in that the flat surface bonding type covered conductor 130' is erected and wound in a horizontal direction (left-right direction) in a manner such that the flat upper surface 130a and the flat lower surface 130b face each other, so that the flat upper surface 130a and the flat lower surface 130b are perpendicular to the lower secondary coil element 210, specifically, perpendicular to the lower insulating portion 212.

[0126] The primary coil 130 includes: a primary side lower layer coil 130L, which is formed by standing the adhesive coated wire 130' and winding it in a spiral shape in the horizontal direction in a manner that the flat upper surface 130a and the flat lower surface 130b face each other, so that the flat upper surface 130a and the flat lower surface 130b are perpendicular to the lower secondary coil element 210, specifically, perpendicular to the lower insulating portion 212; a primary side upper layer coil 130H, which extends upward from the primary side lower layer coil 130L, and is formed by standing the adhesive coated wire 130' and winding it in a spiral shape in the horizontal direction in a manner that the flat upper surface 130a and the flat lower surface 130b face each other, so that it is closely attached to the side of the primary side lower layer coil 130L, and the flat upper surface 130a and the flat lower surface 130b are perpendicular to the lower secondary coil element 210 corresponding to the primary side lower layer coil 130L.

[0127] The primary coil 130 is wound such that the flat upper surface 130 a and the flat lower surface 130 b are in close contact with each other and extend in the horizontal direction.

[0128] Specifically, the primary side lower coil 130L is wound into a spiral shape so that the flat upper surface 130a and the flat lower surface 130b are closely attached to each other and extend in the horizontal direction, and the primary side upper coil 130H is wound into a spiral shape so that the flat upper surface 130a and the flat lower surface 130b are closely attached to each other and extend in the horizontal direction.

[0129] Among them, Figure 6 As shown in part (a) of FIG. 1 , the primary coil 130 in which the flat surface adhesive coated conductive wire 130 ′ is extended in the horizontal direction and wound is referred to as a horizontally extended flat surface primary coil 130 .

[0130] On the other hand, according to the embodiment, the primary side upper layer coil and lower layer coil 130H, 130L may be formed into a spiral shape in the horizontal direction while a gap is formed between the flat upper surface 130a and the flat lower surface 130b.

[0131] Here, a winding method of the horizontally extended flat surface primary coil 130 will be briefly described.

[0132] like Figure 6 As shown in part (b), the primary side upper layer coil 130H is formed by winding it in a counterclockwise direction as one direction R with the center P of the flat surface adhesive coated conductor 130' as a reference, and the primary side lower layer coil 130L is formed by winding it in a counterclockwise direction as one direction L with the center P as a reference.

[0133] As described above, since the primary coils 110, 120, 130 of the vehicle charger transformer are formed in a manner facing each other and in close contact, the close contact between the primary coils 110, 120, 130 of the vehicle charger transformer is increased, and the close contact between the primary coils 110, 120, 130 and the secondary coil is also increased, thereby reducing losses, thereby further improving efficiency, and further reducing the product height, while the product size can be further miniaturized.

[0134] Furthermore, since the height of the transformer for the on-board charger is reduced and the size of the product is reduced, the size of the on-board charger itself can be reduced, thereby reducing the occupied space and weight in the electric vehicle, thereby improving the product competitiveness of the on-board charger in the electric vehicle.

[0135] The thickness t of the primary coils 120 and 130 is 0.1 to 1.0 mm, and the width w thereof is 2.0 to 10.0 mm.

[0136] Preferably, the thickness t of the primary coils 120 and 130 is 0.3 to 0.8 mm, and the width w thereof is 3.0 to 8.0 mm.

[0137] More preferably, the thickness t of the primary coils 120 and 130 is 0.4 to 0.7 mm, and the width w is 4.0 to 7.0 mm.

[0138] Figure 6 The primary coil 130 and Figure 7 The primary coil 140 shown in the figure is an example in which circular first central holes C3 and C4 are formed and wound into a circular shape, but this is only an example for convenience of explanation, and of course, it can also be Figure 6 The primary coil 130 and Figure 7 The primary coil 140 shown in FIG. Figures 1 to 5 The primary coils 110 and 120 shown are similarly arranged so as to be formed with square first center holes C1 and C2 and to be wound in a square shape, and this also belongs to the technical scope of the present invention.

[0139] Next, based on Figure 7 The other primary coil 140 is described.

[0140] like Figure 7 As shown, the conductive wire 140 - 1 of the adhesive-type covered conductor 140 ′ of the primary coil 140 is composed of a thin copper wire 140 - 1 obtained by twisting a plurality of thin copper wires Li.

[0141] The primary coil 140 further includes: a first input terminal 144, which is conductively connected to the end of the input wire portion 141 and forms a first input terminal fixing hole 144a; and a first output terminal 145, which is conductively connected to the end of the output wire portion 143 and forms a first output terminal fixing hole 145a.

[0142] As a result, the wiring work of the transformer A in the vehicle charger can be performed more easily and conveniently.

[0143] The primary coil 140 is wound such that the input wire portion 141 and the output wire portion 143 are arranged to face the charger side of the electric vehicle in the same direction.

[0144] Next, the structure of the secondary coil will be described.

[0145] The lower secondary coil element 210 includes: a plate-shaped lower copper plate coil 211, which is formed by winding a thin copper plate into a spiral shape; a lower insulating portion 212 made of synthetic resin, which is formed with a lower central hole 210a, and contains the lower copper plate coil 211 except the lower terminals 211a and 211c of the lower copper plate coil 211. The upper secondary coil element 220 includes: a plate-shaped upper copper plate coil 221, which is formed by winding a thin copper plate into a spiral shape; an upper insulating portion 222 made of synthetic resin, which is formed with an upper central hole 220a, and contains the upper terminals 221 except the upper copper plate coil 221. a, 221c, the upper copper plate coil 221, the primary coil 110, 120, 130, 140 is characterized in that the lower surface is in close contact with the upper surface 210b of the lower secondary coil element 210 (that is, it is also the upper surface of the lower insulating portion 212), and the upper surface of the primary coil 110, 120, 130, 140 is in close contact with the lower surface 220b of the upper secondary coil element 220 (that is, it is also the lower surface of the upper insulating portion 222), so that the primary coil 110, 120, 130, 140 is closely arranged between the lower secondary coil element 210 and the upper secondary coil element 220.

[0146] Thus, by configuring the primary coil (110, 120, 130, 140) of the on-board charger transformer to be flat, the height can be reduced by 60% compared to the existing on-board charger transformer, and the product size can be further miniaturized (can be reduced by 55% compared to the existing on-board charger transformer).

[0147] Furthermore, since the height of the transformer for the on-board charger is reduced and the size of the product is reduced, the size of the on-board charger itself can be reduced, thereby reducing the occupied space and weight in the electric vehicle, thereby improving the product competitiveness of the on-board charger in the electric vehicle.

[0148] Furthermore, by configuring the coil using a flat copper wire whose upper and lower surfaces are formed into flat surfaces, it is advantageous to transform a large current and can reduce electrical loss and heat generation.

[0149] In addition, the efficiency can be improved by reducing the loss between the primary coil and the secondary coil elements in the on-board charger of electric vehicles.

[0150] Furthermore, by configuring the coil using a flat copper wire whose upper and lower surfaces are formed into flat surfaces, it is advantageous to transform a large current and can reduce electrical loss and heat generation.

[0151] According to the specific structures of the primary coils 110, 120, 130, 140 and the secondary coil elements 210, 220 as described above, a large current and a high voltage can be supplied even if the size is small.

[0152] Furthermore, since there is no need to use a separate bobbin or double shell for fixing the primary coil, the heat generation characteristics are excellent and the electromagnetic interference resistance performance is improved.

[0153] The structures of the upper secondary coil element 220 and the lower secondary coil element 210 will be described in detail below.

[0154] The lower secondary coil element 210 is formed of an inflexible copper plate having a thickness greater than a standard thickness and a cross-sectional area greater than a standard thickness, and the upper secondary coil element 220 is formed of an inflexible copper plate having a thickness greater than a standard cross-sectional area greater than a standard thickness.

[0155] As described above, configuring a non-flexible thick copper plate as a secondary coil element is advantageous for converting large currents and high voltages.

[0156] The lower copper plate coil 211 includes: a lower first terminal 211a, which is formed with a terminal hole 211a'; a lower spiral portion 211b, which is formed with a gap to prevent the copper plates from contacting the lower first terminal 211a and winding multiple times in a spiral shape; a lower second terminal 211c, which is bent downward from the lower spiral portion 211b and then crosses the lower spiral portion 211b in the direction of the lower first terminal 211a. The upper copper plate coil 221 includes: an upper first terminal 221a, which is formed with a terminal hole 221a'; an upper spiral portion 221b, which is formed with a gap to prevent the copper plates from contacting the upper first terminal 221a and winding multiple times in a spiral shape; an upper second terminal 221c, which is bent downward from the upper spiral portion 221b and then crosses the upper spiral portion 221b in the direction of the upper first terminal 221a.

[0157] The transformer A for an on-board charger of an electric vehicle according to an embodiment of the present invention is characterized in that it also includes: a lower bridge portion 211d, which is bent vertically upward from the end of the lower second terminal 211c; an upper bridge portion 221d, which is bent vertically downward from the end of the upper second terminal 221c to contact and electrically connect with the lower bridge portion 211d, and through the connection between the lower bridge portion 211d and the upper bridge portion 221d, the lower secondary coil element 210 and the upper secondary coil element 220 are connected in series.

[0158] The transformer A for an on-board charger of an electric vehicle according to an embodiment of the present invention is characterized in that it also includes: a bridge groove 211e, which is formed by being recessed downward at the end of the lower bridge portion 211d; a bridge protrusion 221e, which is formed by protruding downward at the end of the upper bridge portion 221d, and the bridge protrusion 221e and the bridge groove 211e are inserted and matched with each other, so that the lower bridge portion 211d and the upper bridge portion 221d are in contact and electrically connected.

[0159] The transformer A for an on-board charger of an electric vehicle according to an embodiment of the present invention is characterized in that it further includes: an upper magnetic core 320, which wraps the outer surface of the upper secondary coil element 220 from the upper side of the upper secondary coil element 220; a lower magnetic core 310, which wraps the lower secondary coil element 210 from the lower surface of the lower secondary coil element 210, and in the lower secondary coil element 210, a lower side quasi-coil is formed on one side of the lower surface 210b of the lower secondary coil element (in the figure, the left side where the terminal is located) protruding downward. The protrusion 215, in the upper secondary coil element 220, has an upper quasi-protrusion 225 protruding downward on one side of the upper surface 220c of the upper secondary coil element (in the accompanying drawing, the left side where the terminal is located), and also includes: a lower placement groove 313, which is formed by being recessed downward toward the outside at the middle foot 311 of the lower magnetic core 310 to cooperate with the lower quasi-protrusion 215; an upper placement groove 323, which is recessed upward toward the outside from the middle foot 321 of the upper magnetic core 320 to cooperate with the upper quasi-protrusion 225.

[0160] Therefore, by forming placement grooves 313 and 323 from the mid-foots 311 and 321 toward the outside as a structure that cooperates with the quasi-protrusions 215 and 225, it has the benefit of being able to easily, accurately and quickly align the upper magnetic core and the lower magnetic core 320 and 310 in the assembly of the primary coil 110, 120, 130, 140, the upper secondary coil element and the lower secondary coil element 210.

[0161] The transformer A for an on-board charger of an electric vehicle according to an embodiment of the present invention is characterized in that the upper surface 210c of the lower secondary coil element and the lower surface 220b of the upper secondary coil element are flat surfaces. In order to be able to fix the outer periphery of the primary coil 110, 120, 130, 140 tightly interposed between the upper surface 210c of the lower secondary coil element and the lower surface 220b of the upper secondary coil element, the outer portion of the upper surface 210c of the lower secondary coil element further includes: an outer protruding frame 214, which is formed by protruding upward from the lower insulating portion 212; and an inner protruding frame 213, which is in contact with the inner periphery of the first central holes C1, C2, C3, C4 of the primary coils 110, 120, 130, 140 and is used to fix the inner periphery of the first central holes C1, C2, C3, C4 of the primary coils 110, 120, 130, 140.

[0162] Preferably, as shown in the figure, the inner protruding frame 213 is formed to protrude along the first central holes C1, C2, C3, and C4.

[0163] Furthermore, the present invention is characterized in that in order to make the primary coil 110 be located at the same position as the upper copper plate coil 221 and the lower copper plate coil 211 in the up and down direction (that is, at a position aligned with the center in the up and down direction), the primary coils 110, 120, 130, 140 are fixed so as to be aligned with the center and not eccentric relative to the upper copper plate coil 221 and the lower copper plate coil 211.

[0164] Preferably, the upper secondary coil element 220 prevents gaps or movement of the primary coils 110 , 120 , 130 , and 140 by pressing the primary coils 110 , 120 , and 130 .

[0165] The lower insulating portion 212 is formed by insert molding through resin injection after the lower copper plate coil 211 is embedded in an injection mold, and the upper insulating portion 222 is formed by insert molding through resin injection after the upper copper plate coil 221 is embedded in an injection mold.

[0166] The lower insulating portion 212 and the upper insulating portion 222 are formed by insert molding by resin injection after the lower copper plate coil 211 and the second flat coil 211 are embedded in an injection mold.

[0167] Preferably, the present invention is characterized in that the inner protruding frame 213 and the outer protrusion 124 are formed integrally with the lower insulating portion 212 by insert molding.

[0168] Thus, there is an advantage that the inner protruding frame 213 , the outer protrusion 124 , and the lower insulating portion 212 can be simultaneously formed by a single injection molding process.

[0169] Preferably, the lower copper plate coil 211 and the upper copper plate coil 221 are formed to have a thickness of 1.8 to 2.2 mm.

[0170] More preferably, the lower copper plate coil 211 and the upper copper plate coil 221 are formed to have a thickness of 2.0 mm.

[0171] The transformer A for an on-board charger of an electric vehicle according to an embodiment of the present invention is characterized in that it also includes: a flat base 411; a mounting member 400, which includes an outer portion 412 formed upward from the edge of the base 411, and a placement space Sa is formed inside, for mounting the lower magnetic core 310, the lower secondary coil element 210, the primary coils 110, 120, 130, 140, the upper secondary coil element 220 and the upper magnetic core 320 in the placement space Sa without movement or gap.

[0172] Furthermore, a transformer A for an on-board charger of an electric vehicle according to an embodiment of the present invention is characterized in that an outer portion 412 of the mounting member 400 is formed in a square shape, a second through groove 414 is formed on a left side 412a of the outer portion 412 where the terminals 211a and 221a of the secondary coil elements 210 and 220 are located, so that multiple terminals of the secondary coil elements can pass through to be connected to the secondary side connection pin P2, a first through groove 413 is formed on a right side 412b of the outer portion 412 where the terminals of the primary coils 110, 120, 130, and 140 are located, so that the primary side terminal block 127 fastened with the primary side terminal pin P1 can pass through, and further includes: an insertion plate 216, which is formed to protrude downward from the left end of the lower surface 210b of the lower secondary coil element 210; and an insertion slit 416, which is formed to be recessed downward at the upper end of the left side surface 413 where the second through groove 414 is located, so as to be inserted and fastened to the insertion plate 216.

[0173] A transformer A for an on-board charger of an electric vehicle according to an embodiment of the present invention is characterized in that a primary side terminal block 217 is formed extending from the right side of the lower insulating portion 212 of the lower secondary coil element 210 and fastened with a primary side terminal pin P1, and a reinforcing plate 417 is formed protruding from the edge of a base 411 at the position where the first through groove 413 is located so as to extend horizontally from the base 411 directly below the primary side terminal block 127, and a pair of primary side terminal holes 417 are formed on the reinforcing plate 417 for fixing the lower portion of a pair of primary side terminal pins P1 fastened to the primary side terminal block 217.

[0174] With a simple structure, the secondary terminal pin P2 can be supported from below and above at the same time and firmly fixed.

[0175] The preferred embodiments of the present invention have been observed above. In addition to the above embodiments, it is obvious that a person skilled in the art of the present invention can implement the present invention in other specific embodiments without changing the technical ideas or essential features of the present invention. Therefore, the above embodiments should be understood as exemplary rather than restrictive.

[0176] The scope of the present invention is embodied by the appended claims rather than the above detailed description, and all changes or modifications derived from the meaning, scope and equivalent concepts of the claims should be interpreted as being included in the scope of the present invention.

Claims

1. A transformer for an on-board charger of an electric vehicle, which is used as an on-board charger of an electric vehicle for charging a high-voltage battery of the electric vehicle with a common AC power (220V AC) supplied from a charger of the electric vehicle, characterized in that: include: A flat primary coil (110, 120, 130, 140) for receiving current from a charger of an electric vehicle; a lower secondary coil element (210) which is disposed below the primary coil (110, 120, 130, 140) and is closely attached to the lower surface of the primary coil (110, 120, 130, 140), and generates an induced current through the current flowing in the primary coil (110, 120, 130, 140) and outputs the induced current to a high voltage battery; as well as An upper secondary coil element (220) is disposed above the primary coil (110, 120, 130, 140) and in close contact with the upper surface of the primary coil (110, 120, 130, 140), and generates an induced current through the current flowing in the primary coil (110, 120, 130, 140) and outputs the induced current to the high voltage battery. The primary coil (110, 120, 130, 140) is composed of an adhesive coated conductor (110', 120', 130', 140'), in which a conductive wire (110-1, 120-1, 130-1, 140-1) is coated with an insulating tape (110-2, 120-2, 130-2, 140-2), and an adhesive layer (110-3, 120-3, 130-3, 140-3) is formed by applying an adhesive to the outer peripheral surface of the coated insulating tape (110-2, 120-2, 130-2, 140-2), After the adhesive coated wires (110', 120', 130', 140') are wound multiple times to form a first central hole (C1, C2, C3, C4) in the center, the coated adhesive layer (110-3, 120-3, 130-3, 140-3) is melted and solidified, so that the adhesive coated wires (110', 120', 130', 140') wound closely to each other are joined to each other by welding and formed into a coil shape.

2. The transformer for an on-board charger of an electric vehicle according to claim 1, characterized in that: The primary coil (110, 120, 130, 140) includes: An input wire section (111, 121, 131, 141) connected to the charger side of the electric vehicle and formed of a linear adhesive coated wire (110', 120', 130', 140'); A primary winding portion (112, 122, 132, 142) extending from the input wire portion (111, 121, 131, 141) and used to wind the adhesive-type coated wire (110', 120', 130', 140') in a flat plate shape multiple times to form a first central hole (C1, C2, C3, C4) in the center; The output wire section (113, 123, 133, 143) is formed of a linear adhesive coated wire (110', 120', 130', 140') and is connected to the charger side of the electric vehicle at the terminal of the primary winding section (112, 122, 132, 142). The primary side winding portion (112, 122, 132, 142) is automatically wound in a flat plate shape using a winding member so that the adhesive coated wires (110', 120', 130', 140') are closely attached to each other and aligned in the horizontal direction and / or vertical direction, and then the applied adhesive layer (110-3, 120-3, 130-3, 140-3) is melted and solidified, so that the adhesive coated wires (110', 120', 130', 140') are joined to each other by welding and formed into an aligned and solid state.

3. The transformer for the on-board charger of the electric vehicle according to claim 2, characterized in that: The side portions (110c, 110d) of the adhesive coated conductor (110') of the primary coil (110) are composed of a flat left surface (110c) and a flat right surface (110d) formed as flat surfaces. The primary coil (110) is formed by winding an adhesive coated conductor (110') in a spiral shape in a horizontal direction in such a manner that the flat left surface (110c) and the flat right surface (110d) are in close contact with each other.

4. The transformer for an on-board charger of an electric vehicle according to claim 2, characterized in that: The width (w1) of the adhesive coated conductor (120') forming the primary coil (120) is greater than its thickness (t1), The primary coil (120) is formed by spirally forming the adhesive coated conductor (120') along a vertical direction, which is an up-down direction, in such a manner that a flat upper surface (120a) and a flat lower surface (120b) face each other.

5. The transformer for an on-board charger of an electric vehicle according to claim 2, characterized in that: The width (w) of the adhesive coated conductor (130') forming the primary coil (130) is greater than its thickness (t). The primary coil (130) is formed by standing the adhesive coated conductor (130') upright and winding it in a horizontal direction in a manner such that a flat upper surface (130a) and a flat lower surface (130b) face each other, and the flat upper surface (130a) and the flat lower surface (130b) are perpendicular to the lower secondary coil element (210).

6. The transformer for an on-board charger of an electric vehicle according to claim 5, characterized in that: The primary coil (130) comprises: A primary side lower layer coil (130L) formed by standing the adhesive coated conductor (130') upright and winding it into a spiral shape in a horizontal direction in such a way that the flat upper surface (130a) and the flat lower surface (130b) face each other, so that the flat upper surface (130a) and the flat lower surface (130b) are perpendicular to the lower secondary coil element (210); The primary side upper coil (130H) extends upward from the primary side lower coil (130L), and is formed by standing the adhesive coated conductor (130') upright and winding it into a spiral shape in the horizontal direction in a manner such that the flat upper surface (130a) and the flat lower surface (130b) face each other, so as to be closely attached to the side of the primary side lower coil (130L), and the flat upper surface (130a) and the flat lower surface (130b) are perpendicular to the lower secondary coil element (210) corresponding to the primary side lower coil (130L).

7. The transformer for an on-board charger of an electric vehicle according to claim 2, characterized in that: The conductive wire (140-1) of the adhesive-type covered conductor (140') of the primary coil (140) is composed of a thin copper wire (140-1) made by twisting a plurality of thin copper wires (Li).

8. The transformer for an on-board charger of an electric vehicle according to claim 2, characterized in that: The primary coil (140) further includes: a first input terminal (144) which is conductively connected to the end of the input wire portion (141) and is formed with a first input terminal fixing hole (144a); A first output terminal (145) is conductively connected to the end of the output wire portion (143) and is formed with a first output terminal fixing hole (145a). The primary coil (140) is wound so that the input wire portion (141) and the output wire portion (143) are both arranged toward the charger side of the electric vehicle in the same direction.

9. The transformer for an on-board charger of an electric vehicle according to claim 1, characterized in that: The lower secondary coil element (210) comprises: a plate-shaped lower copper plate coil (211) formed by winding a thin copper plate into a spiral shape; and A lower insulating portion (212) made of synthetic resin is formed with a lower central hole (210a) and contains the lower copper plate coil (211) except for the lower terminals (211a, 211c) of the lower copper plate coil (211). The upper secondary coil element (220) includes: A plate-shaped upper copper plate coil (221) formed by winding a thin copper plate into a spiral shape; An upper insulating portion (222) made of synthetic resin is formed with an upper central hole (220a) and contains the upper copper plate coil (221) except for the upper terminals (221a, 221c) of the upper copper plate coil (221). The lower surface of the primary coil (110, 120, 130, 140) is in close contact with the upper surface (210b) of the lower secondary coil element (210), and the upper surface of the primary coil (110, 120, 130, 140) is in close contact with the lower surface (220b) of the upper secondary coil element (220), so that the primary coil (110, 120, 130, 140) is in close contact with the lower secondary coil element (210) and the upper secondary coil element (220).

10. The transformer for an on-board charger of an electric vehicle according to claim 9, characterized in that: The lower secondary coil element (210) is formed of a non-flexible copper plate having a thickness and a cross-sectional area greater than a standard thickness. The upper secondary coil element (220) is formed of a non-flexible copper plate having a thickness greater than a standard thickness and a cross-sectional area greater than a standard thickness.

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