Conductive path with noise filter

A conductive path with noise filter that enables an efficient reduction in a surge noise in a specific frequency band is provided. A conductive path with noise filter includes a conductive path main body, V-phase wire, W-phase wire, a coil-shaped inductor, V-phase inductor, W-phase inductor surrounding the conductive path main body, V-phase wire, W-phase wire, and a capacitor, V-phase capacitor, W-phase capacitor arranged between the conductive path main body, V-phase wire, W-phase wire and the inductor, V-phase inductor, W-phase inductor.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the priority of Japanese patent application JP2015-137832 filed on Jul. 9, 2015, the entire contents of which are incorporated herein.

TECHNICAL FIELD

The present invention relates to a conductive path with noise filter.

BACKGROUND ART

Patent Document 1 (JP2010-126043A) discloses a technique in which a wire harness including three-phase AC wires is arranged between a motor and an inverter device in an electric vehicle, the wire harness is surrounded by a braided wire in order to take a measure against noise produced by the wire harness, and both ends of the braided wire are connected to a shielding case of the motor and a shielding case of the inverter device. Using the braided wire to shield the wire harness in this manner makes it possible to prevent noise produced by the motor, the inverter device, and the wire harness from affecting surrounding devices or circuits.

SUMMARY

However, it is difficult to efficiently reduce a surge noise in a specific frequency band produced by the inverter device by using a method of surrounding a wire harness using a braided wire.

The present design was accomplished based on the above-mentioned circumstances, and it is an object thereof to provide a conductive path with noise filter that enables an efficient reduction in a surge noise in a specific frequency band.

Solution to Problem

A conductive path with noise filter of the present design includes:

a conductive path main body;

a coil-shaped inductor surrounding the conductive path main body; and

a capacitor arranged between the conductive path main body and the inductor.

Setting the electrostatic capacitance of a capacitor, and setting the inductance of an inductor by varying the winding number, the length or the like of a coil make it possible to efficiently reduce a surge noise in a specific frequency band due to an LC resonance.

DESCRIPTION OF EMBODIMENTS

The conductive path with noise filter of the present design may also have a configuration in which a plurality of the conductive path main bodies are arranged in parallel, the plurality of the conductive path main bodies are each provided with the inductor, and the inductor is a conductive wire coated with an insulating layer. With this configuration, it is possible to prevent the inductors from coming into contact with each other without using dedicated insulating members.

The conductive path with noise filter of the present design may also have a configuration in which the conductive wire according to item (a) is a metal single-core wire. With this configuration, it is possible to keep the inductor in a predetermined coil shape without using other members due to an ability of the metal single-core wire to retain its shape by itself.

The conductive path with noise filter of the present design may also have a configuration in which a plurality of the conductive path main bodies are arranged in parallel, the plurality of the conductive path main bodies are respectively provided with a plurality of the capacitors connected in parallel, and the single inductor surrounds the plurality of the conductive path main bodies all together, and is connected to the plurality of the capacitors.

With this configuration, it is sufficient that only one inductor is used for a plurality of conductive path main bodies, thus making it possible to reduce the number of components.

The conductive path with noise filter of the present design may also include three of the conductive path main bodies constituting a three-phase AC circuit, three of the inductors respectively surrounding the three conductive path main bodies, and three of the capacitors respectively connected to the three inductors, and have a configuration in which the three capacitors are mutually connected via the inductors, the three capacitors are connected to only the inductors, and each of the inductors is connected to only one of the three capacitors and one of the remaining two inductors.

With this configuration, a surge current in each of the conductive path main bodies can be attenuated by the capacitor and the inductor and discharged to another capacitor, thus making it possible to reduce a common mode noise, which is of concern when the capacitor and the inductor are connected to a housing ground such as a motor case.

The conductive path with noise filter of the present design may also have a configuration in which a tubular shielding layer surrounds a plurality of the conductive path main bodies and the inductors all together, and the capacitor is arranged inside a shielded space surrounded by the shielding layer.

With this configuration, the size can be reduced compared with a case where the capacitor is provided on the outside of the shielding layer.

The conductive path with noise filter of the present design may also have a configuration in which the capacitor includes the conductive path main body, an insulating layer surrounding the conductive path main body, and a conductive layer provided to correspond to the conductive path main body with the insulating layer being sandwiched between the conductive layer and the conductive path main body.

With this configuration, a lead wire becomes unnecessary, thus making it unnecessary to connect the conductive path main body and a lead wire.

Hereinafter, Embodiment 1 will be described with reference toFIGS. 1 to 3. A conductive path A with noise filter of Embodiment 1 is arranged between a motor30and an inverter device34mounted in an electric vehicle (not shown) such as an electric car or a hybrid car. In this electric vehicle, a housing ground40is constituted by a motor case31that is a housing of the motor30, an inverter case35that is a housing of the inverter device34, and a shielding layer23that connects the cases31and35. The conductive path A with noise filter includes a U-phase wire11u(“conductive path main body” in the claims), a V-phase wire11v(“conductive path main body” in the claims) and a W-phase wire11w(“conductive path main body” in the claims) that constitute a three-phase AC circuit10, and a surge reducing filter15and the shielding layer23.

The U-phase wire11u, the V-phase wire11v, and the W-phase wire11ware each constituted by a stranded wire or a single-core wire made of metal (e.g., copper, a copper alloy, aluminum, or an aluminum alloy). The outer circumference of the U-phase wire flu is surrounded by a U-phase insulating coating12u(“insulating layer” in the claims) made of a synthetic resin. The outer circumference of the V-phase wire11vis surrounded by a V-phase insulating coating12v(“insulating layer” in the claims) made of a synthetic resin. The outer circumference of the W-phase wire11wis surrounded by a W-phase insulating coating12w(“insulating layer” in the claims) made of a synthetic resin. Specifically, the U-phase wire11uand the U-phase insulating coating12umake up one coated electric wire. The V-phase wire11vand the V-phase insulating coating12vmake up one coated electric wire. The W-phase wire11wand the W-phase insulating coating12wmake up one coated electric wire.

The U-phase wire11u, the V-phase wire11v, and the W-phase wire11ware arranged in parallel. One end of each of the U-phase wire11u, the V-phase wire11v, and the W-phase wire11wis connected to an inverter circuit (not shown) of the inverter device34. The inverter circuit is accommodated inside the conductive inverter case35having a shielding function. The other end of each of the U-phase wire11u, the V-phase wire11v, and the W-phase wire11wis connected to the winding wires of the motor30. The winding wires are accommodated inside the conductive motor case31having a shielding function.

The surge reducing filter15includes a tubular U-phase conductive layer16u(“first conductive layer” in the claims), a tubular V-phase conductive layer16v, and a tubular W-phase conductive layer16w. Each of the U-phase conductive layer16u, the V-phase conductive layer16v, and the W-phase conductive layer16wis made of metal (e.g., copper, a copper alloy, aluminum, or an aluminum alloy) and is not directly connected to the housing ground40. The outer circumference of each of the U-phase conductive layer16u, V-phase conductive layer16v, and the W-phase conductive layer16wis coated with an insulating coating, an insulating film, or the like.

The U-phase wire11uand the U-phase insulating coating12uare surrounded by the U-phase conductive layer16uin a state of being in proximity to each other. In other words, their positional relationship is such that the U-phase conductive layer16uand the U-phase wire11uare in proximity to each other and face each other with the U-phase insulating coating12ubeing sandwiched therebetween. Accordingly, the U-phase wire11u, the U-phase insulating coating12u, and the U-phase conductive layer16uconstitute a U-phase capacitor17u(“capacitor” in the claims), and the U-phase wire11uand the U-phase conductive layer16userve as electrodes.

Also, the V-phase wire11vand the V-phase insulating coating12vare surrounded by the V-phase conductive layer16vin a state of being in proximity to each other. In other words, their positional relationship is such that the V-phase conductive layer16vand the V-phase wire11vare in proximity to each other and face each other with the V-phase insulating coating12vbeing sandwiched therebetween. Accordingly, the V-phase wire11v, the V-phase insulating coating12v, and the V-phase conductive layer16vconstitute a V-phase capacitor17v(“capacitor” in the claims), and the V-phase wire11vand the V-phase conductive layer16vserve as electrodes.

Similarly, the W-phase wire11wand the W-phase insulating coating12ware surrounded by the W-phase conductive layer16win a state of being in proximity to each other. In other words, their positional relationship is such that the W-phase conductive layer16wand the W-phase wire11ware in proximity to each other and face each other with the W-phase insulating coating12wbeing sandwiched therebetween. Accordingly, the W-phase wire11w, the W-phase insulating coating12w, and the W-phase conductive layer16wconstitute a W-phase capacitor17w(“capacitor” in the claims), and the W-phase wire11wand the W-phase conductive layer16wserve as electrodes.

The U-phase conductive layer16u, the V-phase conductive layer16v, and the W-phase conductive layer16ware connected to the motor case31via a housing connection wire18. The housing connection wire18includes a U-phase branch wire19uconnected to the U-phase conductive layer16u, a V-phase branch wire19vconnected to the V-phase conductive layer16v, and a W-phase branch wire19wconnected to the W-phase conductive layer16w.

An intermediate portion of the U-phase branch wire19uis provided with a coil-shaped U-phase inductor20uincluded in the surge reducing filter15. An intermediate portion of the V-phase branch wire19vis provided with a coil-shaped V-phase inductor20vincluded in the surge reducing filter15. An intermediate portion of the W-phase branch wire19wis provided with a coil-shaped W-phase inductor20wincluded in the surge reducing filter15. These three inductors20u,20vand20ware star-connected by the three branch wires19u,19vand19w, and connected to the housing ground40(motor case31) via the housing connection wire18.

Each of the inductors20u,20vand20wis obtained by coating a conductive wire21constituted by a metal single-core wire with an insulating layer22. The conductive wire21coated with the insulating layer22is shaped into a spiral shape, and surrounds the end portion on the motor30side of each of the U-phase wire11u, the V-phase wire11v, and the W-phase wire11w. The conductive wire21shaped into a spiral shape retains its coil shape without using other members because it is constituted by a metal single-core wire.

The shielding layer23is a tubular metal member constituted by a braided wire or the like, for example. One end of the shielding layer23is located near the motor30, and connected to the motor case31such that electrical conduction can be established. The other end of the shielding layer23is located near the inverter device34, and connected to the inverter case35such that electrical conduction can be established. A space surrounded by the shielding layer23serves as a shielded space24. The shielding layer23surrounds the U-phase wire11u, the V-phase wire11v, the W-phase wire11w, the U-phase conductive layer16u, the V-phase conductive layer16v, and the W-phase conductive layer16wall together.

Accordingly, the U-phase wire11u, the V-phase wire11v, the W-phase wire11w, the U-phase inductor20u, the V-phase inductor20v, the W-phase inductor20w, the U-phase capacitor17u, the V-phase capacitor17v, and the W-phase capacitor17w(the U-phase conductive layer16u, the V-phase conductive layer16vand the W-phase conductive layer16w) are accommodated in the shielded space24. The motor case31and the inverter case35are connected to each other by the shielding layer23. It should be noted that a conductive means for connecting the motor case31and the inverter case35is not limited to the shielding layer23, and a stranded wire, a single-core wire, a vehicle body, or the like may also be used.

Next, the functions of this embodiment will be described. After the frequency of a surge voltage produced by the inverter device34has been determined, the lengths of the conductive layers16u,16vand16w, the corresponding areas of the conductive layers16u,16vand16wand the conductive path main body (the U-phase wire11u, the V-phase wire11v, the W-phase wire11w), the distances between the conductive layers16u,16vand16wand the conductive path main body (the U-phase wire11u, the V-phase wire11v, the W-phase wire11w), the materials for the U-phase insulating coating12u, the V-phase insulating coating12vand the W-phase insulating coating12w, and the like are selected as appropriate, setting the electrostatic capacitances of the U-phase capacitor17u, the V-phase capacitor17vand the W-phase capacitor17wsuitable for reducing a surge noise at the determined frequency. Regarding the U-phase inductor20u, the V-phase inductor20v, and the W-phase inductor20w, the materials for and cross-sectional areas of the wires used therein, the winding numbers of the coils, and the like are selected as appropriate, setting their inductances suitable for reducing a surge noise at the determined frequency.

When the electrostatic capacitances of the three capacitors17u,17vand17w, and the inductances of the three inductors20u,20vand20ware set in this manner, a surge current at a specific frequency flows into the motor case31via the inductors20u,20vand20wand the housing connection wire18, and returns to the inverter device34via the shielding layer23, resulting in a reduction of the surge noise.

The conductive path A with noise filter of Embodiment 1 includes the U-phase wire11u, the V-phase wire11vand the W-phase wire11w, which serve as the conductive path main body, and the U-phase inductor20u, the V-phase inductor20vand the W-phase inductor20w, which have a coil shape and are surrounding the U-phase wire11u, the V-phase wire11vand the W-phase wire11w, respectively. The conductive path A with noise filter further includes the U-phase capacitor17uarranged between the U-phase wire flu and the U-phase inductor20u, the V-phase capacitor17varranged between the V-phase wire11vand the V-phase inductor20v, and the W-phase capacitor17warranged between the W-phase wire11wand the W-phase inductor20w. Setting the electrostatic capacitances of the capacitors17u,17vand17w, and setting the inductances of the inductors20u,20vand20was described above make it possible to effectively reduce the surge noise in a specific frequency band due to an LC resonance.

The three wires, namely the U-phase wire11u, the V-phase wire11vand the W-phase wire11w, are arranged in parallel and provided with the U-phase inductor20u, the V-phase inductor20vand the W-phase inductor20w, respectively. In this case, there is a concern that the inductors20u,20vand20ware short-circuited with one another, but, in Embodiment 1, each of the inductors20u,20vand20wis obtained by coating the conductive wire21with the insulating layer22, thus making it possible to prevent the inductors20u,20vand20wfrom coming into contact with one another without using dedicated insulating members. Furthermore, the conductive wire21is a metal single-core wire having an ability to retain its shape by itself, thus making it possible to keep the inductors20u,20vand20win a predetermined coil shape without using other members.

The conductive path A with noise filter of Embodiment 1 includes the housing connection wire18for connecting the conductive layers16u,16vand16wto the housing ground40(motor case31), and this housing connection wire18is provided with the three inductors20u,20vand20w. With this configuration, a surge current flows into the housing40(motor case31) via the housing connection wire18, and returns to the inverter device34via the shielding layer23, resulting in an effective reduction of the surge noise.

The capacitors17u,17vand17wand the inductors20u,20vand20ware arranged inside the shielded space24, which is a dead space inside the shielding layer23. Accordingly, the size can be reduced compared with a case where the capacitors17u,17vand17wand the inductors20u,20vand20ware provided on the outside of the shielding layer23.

The capacitors17u,17vand17weach include the conductive path main body (the U-phase wire11u, the V-phase wire11v, the W-phase wire11w), the insulating layer (the U-phase insulating coating12u, the V-phase insulating coating12v, the W-phase insulating coating12w) that surrounds the conductive path main body (the U-phase wire11u, the V-phase wire11v, the W-phase wire11w), and the conductive layer (the U-phase conductive layer16u, the V-phase conductive layer16v, the W-phase conductive layer16w) that is provided to correspond to the conductive path main body (the U-phase wire11u, the V-phase wire11v, the W-phase wire11w) with the the insulating layer (U-phase insulating coating12u, the V-phase insulating coating12v, the W-phase insulating coating12w) being sandwiched therebetween. With this configuration, the capacitors17u,17vand17winclude no lead wires, thus making it unnecessary to connect lead wires to the U-phase wire11u, the V-phase wire11vand the W-phase wire11w.

Next, Embodiment 2 will be described with reference toFIG. 4. A conductive path B with noise filter of Embodiment 2 has a configuration in which the three inductors20u,20vand20ware connected in a way different from that in Embodiment 1 above. Other structural aspects are identical to those of Embodiment 1 above. Therefore, identical structural aspects are denoted by identical reference numerals, and descriptions of the structures, functions, and effects are omitted.

In Embodiment 1 above, the housing connection wire18for connecting the U-phase capacitor17u(U-phase conductive layer16u), the V-phase capacitor17v(V-phase conductive layer16v) and the W-phase capacitor17w(W-phase conductive layer16w) to the motor case31is provided, and the three branch wires19u,19vand19wof this housing connection wire18are provided with the U-phase inductor20u, the V-phase inductor20v, and the W-phase inductor20w, respectively.

In contrast, in Embodiment 2, the housing connection wire18is not provided, the U-phase capacitor17uand the V-phase capacitor17vare connected via the U-phase inductor20u, the V-phase capacitor17vand the W-phase capacitor17ware connected via the V-phase inductor20v, and the W-phase capacitor17wand the U-phase capacitor17uare connected via the W-phase inductor20w. That is, the three inductors20u,20vand20ware delta-connected. At the end portions on the motor30side of the U-phase wire11u, the V-phase wire11vand the W-phase wire11w, neither the three capacitors17u,17vand17w(conductive layers16u,16vand16w) nor the three inductors20u,20vand20ware connected to the housing ground40.

The conductive path B with noise filter of Embodiment 2 includes the U-phase wire11u, the V-phase wire11vand the W-phase wire11w, which constitute the three-phase AC circuit10; the U-phase inductor20u, the V-phase inductor20vand the W-phase inductor20w, which respectively surround the U-phase wire11u, the V-phase wire11vand the W-phase wire11w; and the three capacitors17u,17vand17w, which are respectively connected to the three inductors20u,20vand20w. The three capacitors17u,17vand17w(conductive layers16u,16vand16w) are mutually connected via the inductors20u,20vand20w.

The conductive layers16u,16vand16wincluded in the three capacitors17u,17vand17ware connected to only the inductors20u,20vand20w. Each of the three inductors20u,20vand20wis connected to only one of the three capacitors17u,17vand17w(conductive layers16u,16vand16w) and one of the remaining two inductors. With this configuration, a surge current in each of the wires11u,11vand11wcan be attenuated by the capacitors17u,17vand17wand the inductors20u,20vand20w, and discharged to the other conductive layers16u,16vand16w, thus making it possible to reduce a common mode noise, which is of concern when the conductive layers16u,16vand16wand the inductors20u,20vand20ware connected to the housing ground40(motor case31).

Next, Embodiment 3 will be described with reference toFIG. 5. A conductive path with noise filter C of Embodiment 3 has a configuration that differs from that of Embodiment 1 above in that an inductor25is used. Other structural aspects are identical to those of Embodiment 1 above. Therefore, identical structural aspects are denoted by identical reference numerals, and descriptions of the structures, functions, and effects are omitted.

In Embodiment 1 above, the three inductors, namely the U-phase inductor20u, the V-phase inductor20vand the W-phase inductor20w, are provided, and the U-phase inductor20u, the V-phase inductor20vand the W-phase inductor20wsurround the U-phase wire11u, the V-phase wire11vand the W-phase wire11w, respectively. In contrast, in Embodiment 3, the number of the inductor25is set to one, and this one inductor25surrounds the three wires, namely the U-phase wire11u, the V-phase wire11vand the W-phase wire11w, all together in a spiral manner. One end of this coil-shaped inductor25is connected to the motor case31. The other end of the inductor25is connected to the end on the motor30side of the U-phase conductive layer16uof the U-phase capacitor17u.

The end on the motor30side of the U-phase conductive layer16uof the U-phase capacitor17uand the end on the motor30side of the V-phase conductive layer16vof the V-phase capacitor17vare connected via an inter-phase connection wire26uv. The end on the motor30side of the V-phase conductive layer16vof the V-phase capacitor17vand the end on the motor30side of the W-phase conductive layer16wof the W-phase capacitor17ware connected via an inter-phase connection wire26vw.

In the conductive path with noise filter C of Embodiment 3, the three wires, namely the U-phase wire11u, the V-phase wire11vand the W-phase wire11w, are arranged in parallel, and the three capacitors, namely the U-phase capacitor17u, the V-phase capacitor17vand the W-phase capacitor17w, which are connected in parallel, are provided on the three wires, namely the U-phase wire11u, the V-phase wire11vand the W-phase wire11w, respectively. One inductor25surrounds the three wires, namely the U-phase wire11u, the V-phase wire11vand the W-phase wire11w, all together, and is connected to the three capacitors, namely the U-phase capacitor17u, the V-phase capacitor17vand the W-phase capacitor17w. With this configuration, it is sufficient that only one inductor25is used for the three conductive path main bodies (i.e., the U-phase wire11u, the V-phase wire11vand the W-phase wire11w), thus making it possible to reduce the number of components.

Next, Embodiment 4 will be described with reference toFIG. 6. A conductive path with noise filter D of Embodiment 4 has a configuration that differs from that of Embodiment 1 above in that a surge reducing filter36is used. Other structural aspects are identical to those of Embodiment 1 above. Therefore, identical structural aspects are denoted by identical reference numerals, and descriptions of the structures, functions, and effects are omitted.

The surge reducing filter36of Embodiment 4 includes two separate U-phase conductive layers16u, one of which is located on the motor30side and the other of which is located on the inverter device34side, two separate V-phase conductive layers16v, one of which is located on the motor30side and the other of which is located on the inverter device34side, and two separate W-phase conductive layers16w, one of which is located on the motor30side and the other of which is located on the inverter device34side. The U-phase conductive layer16u, the V-phase conductive layer16vand the W-phase conductive layer16wlocated on the motor30side are not directly connected to the U-phase conductive layer16u, the V-phase conductive layer16vand the W-phase conductive layer16wlocated on the inverter device34side, respectively. The U-phase wire11u, the V-phase wire11vand the W-phase wire11wrespectively include two separate U-phase capacitors17u, one of which is located on the motor30side and the other of which is located on the inverter device34side, two separate V-phase capacitors17v, one of which is located on the motor30side and the other of which is located on the inverter device34side, and two separate W-phase capacitors17w, one of which is located on the motor30side and the other of which is located on the inverter device34side.

Furthermore, the surge reducing filter36of Embodiment 4 also includes three inductors20u,20vand20wthat are respectively connected to the U-phase conductive layer16u, the V-phase conductive layer16vand the W-phase conductive layer16wlocated on the motor30side, and three inductors20u,20vand20wthat are respectively connected to the U-phase conductive layer16u, the V-phase conductive layer16vand the W-phase conductive layer16wlocated on the inverter device34side. The three inductors20u,20vand20wlocated on the motor30side are star-connected, and are connected to the housing ground40(motor case31) via a housing connection wire18. The three inductors20u,20vand20wlocated on the inverter device34side are star-connected, and are connected to the housing ground40(inverter case35) via a housing connection wire18.

Other Embodiments

The present invention is not limited to the embodiments that have been described above with reference to the drawings, and embodiments such as those described below are also included in the technical scope of the present invention, for example.

Although, in Embodiments 1 to 4 above, the capacitors each include the conductive path main body, the insulating layer surrounding the conductive path main body, and the conductive layer provided to correspond to the conductive path main body with the insulating layer being sandwiched therebetween, each of the capacitors may also include a lead wire that is to be connected to the conductive path main body.

Although, in Embodiments 1 to 4 above, the shielding layer surrounds the plurality of conductive path main bodies all together, a configuration in which such a shielding layer is not provided may also be possible.

Although, in Embodiments 1, 3 and 4 above, the three conductive path main bodies constituting the three-phase AC circuit are star-connected, the present invention can also be applied to a case where three conductive path main bodies constituting a three-phase AC circuit are delta-connected. The present invention can also be applied to a case where the delta-connection is changed to star-connection in Embodiment 2.

Although, in Embodiments 1 to 4 above, the three conductive path main bodies constitute the three-phase AC circuit, the present invention can also be applied to a case where the conductive path main bodies do not constitute a three-phase AC circuit.

Although, in Embodiments 1 to 4 above, the number of the conductive path main bodies is three, the present invention can also be applied to a case where the number of the conductive path main bodies is one, two, or four or more.

Although, in Embodiments 1 to 4 above, the flexible stranded wires or single-core wires having a circular cross section are used as the conductive path main bodies, busbars that are not deformed easily, flat cables in which a plurality of electric wires are arranged in parallel, or the like may also be used.

Although, in Embodiments 1 to 4 above, each of the insulating layers are integrated with the outer circumference of the conductive path main body and included in the coated wire, each of the insulating layers may also be integrated with the inner circumference of the conductive layer, or arranged between the outer circumference of the conductive path main body and the inner circumference of the conductive layer so as to be capable of being displaced relatively.

Although, in Embodiments 1 to 4 above, the conductive path with noise filter is arranged between the motor and the inverter device, the present invention can also be applied to a case where the conductive path with noise filter is to be connected to devices other than the motor and the inverter device.

Although, in Embodiments 1, 3 and 4 above, the housing connection wire is connected to the motor case, the housing connection wire may also be connected to not the motor case but the vehicle body (ground) directly.

Although, in Embodiments 1 to 4 above, the inductors have a configuration in which the conductive wire is coated with the insulating layer, the inductors may also have a configuration in which the conductive wire is exposed. In this case, it is necessary to provide insulating members for preventing the inductors from coming into contact with each other and preventing the inductors from coming into contact with the shielding layer.

Although, in Embodiments 1 to 4 above, the single-core wires are used as the conductive wires of the inductors, stranded wires may also be used as the conductive wires.

Although, in Embodiments 1 to 4 above, each of the conductive layers corresponds to the conductive path main body and surrounds the entire circumference thereof, each of the conductive layers may be configured to correspond to only a partial region of the conductive path main body in a circumferential direction.

Although, in Embodiments 1 to 3 above, the inductors are arranged on only the motor side and connected to only the motor case, inductors may also be provided on the inverter device side in addition to the inductors on the motor side, and connected to the inverter case.

Although, in Embodiments 1 to 4 above, the conductive layers are made of metal having a tubular shape, sheet-like or tape-like metal foils, braided wires, metal busbars, metal stranded wires, metal single-core wires, core materials with a plated surface, conductive resins, conductive rubbers, or the like may also be used.

Although, in Embodiments 1 to 4 above, the metal single-core wires are used as the inductors, metal stranded wires may also be used as the inductors.

Although, in Embodiments 1 to 4 above, the conductive layers are directly connected to only the inductors, there is no limitation thereto. Components such as resistances that independently exhibit a noise filtering function, components that exhibit a noise filtering function together with the conductive layers and the inductors, or the like may also be connected to the conductive layers in parallel with the inductors.

LIST OF REFERENCE NUMERALS