CN214626715U - Motor inverter - Google Patents

Abstract

The utility model discloses a motor inverter, include: the first busbar and the second busbar as well as a first copper sheet and a second copper sheet which are led out from a shell of the motor inverter; the first busbar and the second busbar are arranged in a laminated manner; the first copper sheet is arranged on one side of the first busbar away from the second busbar; in a plane parallel to the first plane, the first copper sheet is at least partially overlapped with the first busbar; the second copper sheet is arranged on one side of the second busbar away from the first busbar; and in a second plane parallel to the first plane, the first copper sheet is at least partially overlapped with the first busbar. The utility model provides a technical scheme adopts the electromagnetic compatibility forward design, through the copper sheet of the female certain distance of arranging of drawing forth distance on motor inverter's casing, constructs the distribution electric capacity of arranging between female row and the copper sheet, realizes common mode filtering effect, improves electromagnetic interference EMI's grade, when saving installation space, still not receive parasitic inductance's restriction, and applicable frequency range is wider.

Description

Motor inverter

Technical Field

The utility model relates to a new energy automobile technical field especially relates to a motor inverter.

Background

Compared with the traditional fuel oil automobile, the new energy automobile has the advantages of energy conservation and environmental protection, the development of the new energy automobile is valued and welcomed by all communities, and then faces some new challenges, and Electromagnetic Compatibility (EMC) is one of the new challenges. As a vehicle-mounted high-power component, a motor inverter is continuously developed in a direction of light weight, small size and high efficiency, wherein a switching speed of a power module is also higher, and further, an Electromagnetic Interference (EMI) generated is larger and wider in energy and frequency band, and the Electromagnetic Interference becomes a main Interference source in a new energy vehicle. The electromagnetic interference generated by the motor inverter is not only related to the reliability of the work of the motor inverter, but also can affect the safe operation capacity of the whole automobile and adjacent automobiles, and is the biggest obstacle for the automobile to meet relevant electromagnetic compatibility standards. The research on the generation mechanism and the suppression method of the electromagnetic interference of the motor inverter has important significance on the development of new energy automobiles.

In the industry, the optimization of electromagnetic compatibility of automobiles is mostly focused on the research of the whole automobile level, or the optimization design of the electromagnetic compatibility of a motor inverter is mostly designed in a reverse direction, and a mode of additionally increasing a direct-current bus filter inductor on the manufactured finished motor inverter is mostly adopted, for example, a magnetic ring is sleeved at a high-voltage wire inlet end of the motor inverter, so that the required installation space is large, the filtering effect on common-mode interference is limited, and the improvement of the electromagnetic interference EMI level is limited.

SUMMERY OF THE UTILITY MODEL

The embodiment of the utility model provides a motor inverter adopts the electromagnetic compatibility forward design, through draw forth the copper sheet of female certain distance of arranging of distance on motor inverter's casing, constructs the distributed capacitance who arranges between female row and the copper sheet, realizes common mode filtering effect, improves electromagnetic interference EMI's grade, when saving installation space, still not receive parasitic inductance's restriction, and applicable frequency range is wider.

The embodiment of the utility model provides a motor inverter, including first female arranging and second female arranging to and follow first copper sheet and the second copper sheet that draws forth on motor inverter's the casing;

the first busbar and the second busbar are arranged in a laminated manner;

the first copper sheet is arranged on one side of the first busbar, which is far away from the second busbar; in a first plane, the first copper sheet is at least partially overlapped with the first busbar;

the second copper sheet is arranged on one side of the second busbar, which is far away from the first busbar; and in a second plane parallel to the first plane, the first copper sheet is at least partially overlapped with the first busbar.

Optionally, in a plane parallel to the first plane, the first copper sheet is completely overlapped with the first busbar; and in a plane parallel to the second plane, the second copper sheet is completely overlapped with the second busbar.

Optionally, the first copper sheet is a first distance away from the first busbar; the second copper sheet is away from the second busbar by a second distance; the first distance and the second distance are greater than zero.

Optionally, the first distance is D1, the second distance is D2, wherein D1 is greater than or equal to 0.8mm and less than or equal to 1.2 mm; d2 is not less than 0.8mm and not more than 1.2 mm.

Optionally, an overlapping portion of the first copper sheet and the first busbar is filled with a first medium with a first dielectric constant; and the overlapping part of the second copper sheet and the second busbar is filled with a second medium with a second dielectric constant.

Optionally, the first medium and the second medium include an insulating glue;

the first and second dielectric constants are 10.

Optionally, the system further comprises a direct current bus capacitor;

the first busbar is provided with a first connecting point; the second busbar is provided with a second connecting point; the first connection point and the second connection point are used for connecting the direct current bus capacitor.

Optionally, the first busbar is provided with a first via hole; the second busbar is provided with a second through hole; the first via hole and the second via hole are used for connecting a direct current input power supply.

Optionally, the system further comprises a power module; the power module includes a switching device;

the first busbar is provided with a third connecting point; the second busbar is provided with a fourth connecting point; the third connection point and the fourth connection point are used for connecting the switching device.

Optionally, the switching device includes an insulated gate bipolar transistor, or a metal-oxide semiconductor field effect transistor, or an integrated gate commutated thyristor.

The utility model discloses in, through drawing forth first copper sheet and second copper sheet from motor inverter's casing, set up first copper sheet in the first mother row and keep away from one side of second mother row, the second copper sheet sets up in the second mother row and keeps away from one side of first mother row, and set up first copper sheet and the at least partial overlap of first mother row, the second copper sheet overlaps with the at least partial overlap of second mother row, the technical scheme that the embodiment of the utility model provides, adopt the electromagnetic compatibility forward design, set up first copper sheet and second copper sheet that draw forth from inverter casing in first mother row and second mother row both sides, construct the distributed capacitance between first mother row and the first copper sheet, and the distributed capacitance between second mother row and the second copper sheet, realize common mode filtering's effect, when improving the electromagnetic interference EMI grade, still saved installation space; in addition, the constructed distributed capacitance is almost pure capacitive and is not limited by parasitic inductance, so that the applicable frequency range is wider.

Drawings

Fig. 1 is a schematic structural diagram of a motor inverter according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a portion of the motor inverter provided in FIG. 1;

fig. 3 is a schematic diagram of the distribution of electric field lines of a parallel plate capacitor according to an embodiment of the present invention;

fig. 4 is an effect diagram of implementing common mode filtering by using distributed capacitors according to an embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

Fig. 1 is a schematic structural diagram of a motor inverter provided in an embodiment of the present invention, and fig. 2 is a schematic structural diagram of a part of the motor inverter provided in fig. 1. Referring to fig. 1 and 2, the motor inverter 1 includes: the motor inverter comprises a first busbar 10, a second busbar 20, a first copper sheet 30 and a second copper sheet 40, wherein the first copper sheet and the second copper sheet are led out from a shell of the motor inverter 1; the first busbar 10 and the second busbar 20 are arranged in a laminated manner; the first copper sheets 30 are arranged on one side of the first busbar 10 away from the second busbar 20; in a first plane, the first copper sheet 30 is at least partially overlapped with the first busbar 10; the second copper sheets 40 are arranged on one side of the second busbar 20 far away from the first busbar 10; in a second plane parallel to the first plane, the first copper sheet 40 at least partially overlaps the first busbar 20.

With the development of motor inverters towards light, small and high efficiency, the switching speed of the switching devices of the power modules is higher and higher, and the generated electromagnetic interference is larger and larger. The electromagnetic interference signal with large energy and wide frequency band generated by the switching device is generally output through a busbar of the motor inverter, and influences the electromagnetic compatibility of the motor inverter. In the prior art, the technical scheme for realizing common-mode filtering is to take remedial measures when electromagnetic interference occurs after a motor inverter is manufactured, namely, a magnetic ring sleeve is additionally arranged outside a high-voltage wire inlet end, so that the problem of large occupied installation space exists. The embodiment of the utility model provides a through the first both sides of arranging 10 and the female row 20 of second that set up at the stromatolite, draw forth from motor inverter 1's casing with the first copper sheet 30 of arranging 10 parallel arrangement of first row, and arrange 20 parallel arrangement's the second copper sheet 40 with the second, and first copper sheet 30 sets up in the first one side of arranging 10 and keeping away from the female row 20 of second row, second copper sheet 40 sets up in the female one side of arranging 20 and keeping away from first row 10 of second, can utilize the distribution parameter effect between the parallel metal plate structure to establish the distributed capacitance between the first row 10 and the first copper sheet 30, and the female distributed capacitance between 20 of second row and the second copper sheet 40.

Fig. 3 is a schematic diagram of the distribution of electric field lines of a parallel plate capacitor according to an embodiment of the present invention. As shown in fig. 3, a distributed capacitance is generated between two parallel metal surfaces, and the capacitance of the distributed capacitance can be calculated by the following formula one:

wherein C is the capacitance value of the distributed capacitance and the unit is farad (F); epsilon₀The dielectric constant of the vacuum is 8.854 × 10^-12F/M; epsilon is the dielectric constant of the insulating medium filled between the two parallel metal surfaces; a is the overlapping area between two parallel metal surfaces; d is the perpendicular distance between two parallel metal planes. With continued reference to fig. 2 and fig. 3, a first copper sheet 30, which is disposed in parallel to the first busbar 10 and at a certain distance from the first busbar, is led out from the housing of the motor inverter 1, so as to form a first distributed capacitor, and the capacitance value of the first distributed capacitor is related to the dielectric constant of the insulating medium between the first busbar 10 and the first copper sheet 30, the overlapping area between the first busbar 10 and the first copper sheet 30, and the vertical distance between the first busbar 10 and the first copper sheet 30; a second copper sheet 40 which is arranged in parallel with the second busbar 20 and is at a certain distance is led out from the shell of the motor inverter 1, so that a second distributed capacitor can be formed, and the capacitance value of the second distributed capacitor is related to the dielectric constant of an insulating medium between the second busbar 20 and the second copper sheet 40, the overlapping area between the second busbar 20 and the second copper sheet 40, and the vertical distance between the second busbar 20 and the second copper sheet 40.

The embodiment of the utility model provides a technical scheme adopts the electromagnetic compatibility forward design, initiatively sets up first copper sheet and the second copper sheet of drawing forth from the inverter housing in the process of motor inverter manufacturing at first female arranging and second female arranging both sides, founds the distributed capacitance between first female arranging and the first copper sheet to and the distributed capacitance between second female arranging and the second copper sheet, can realize common mode filtering's effect, improved electromagnetic interference EMI grade; meanwhile, the problem that a large installation space is occupied because a magnetic ring sleeve is additionally arranged outside a high-voltage wire inlet end because remedial measures are taken only after the motor inverter generates electromagnetic interference is solved; in addition, the constructed distributed capacitor is almost pure capacitive and is not limited by parasitic inductance, so that the capacitive change is not large when the frequency is increased, and the applicable frequency range is wider.

Optionally, as shown in fig. 1 and fig. 2, in a plane parallel to the first plane, the first copper sheet 30 and the first busbar 10 may completely overlap; in a plane parallel to the second plane, the second copper sheets 40 and the second busbar 20 may completely overlap. The embodiment of the utility model provides a can be according to actual need's the first copper sheet 30 of the appearance value size adjustment of distributed capacitance and the first area of overlapping between arranging 10 to and the second copper sheet 40 and the second overlap the area of overlapping between arranging 20, preferred, can set up first copper sheet 30 and the first row of arranging 10 and overlap completely, and second copper sheet 40 and the female 20 of arranging of second overlap completely, in order to reach better common mode filtering effect.

Optionally, as shown in fig. 1 and fig. 2, the first copper sheet 30 is spaced from the first busbar 10 by a first distance; the second copper sheets 40 are spaced from the second busbar 20 by a second distance; the first distance and the second distance may be greater than zero. The embodiment of the utility model provides a can be according to actual need's the appearance value size of distribution electric capacity to and the setting position condition of other parts on the 1 casing of motor inverter, adjust the first distance between first copper sheet 30 and the first female row 10 in a flexible way, and the second distance between female row 20 of second copper sheet 40 and second, it is preferred, first distance and second distance all are greater than zero, in order to ensure to form distribution electric capacity.

Optionally, the first distance may be D1, and the second distance may be D2, wherein D1 is 0.8mm or less and 1.2mm or less; d2 is not less than 0.8mm and not more than 1.2 mm. Preferably, the embodiment of the utility model provides a technical scheme, its first distance D1's value range is that 0.8mm is less than or equal to D1 and is less than or equal to 1.2mm, and second distance D2's value range is that 0.8mm is less than or equal to D2 and is less than or equal to 1.2mm to reach better common mode filtering effect.

Optionally, as shown in fig. 2, the overlapping portion of the first copper sheet 30 and the first busbar 10 may be filled with a first medium M1 with a first dielectric constant ∈ 1; the overlapping portion of the second copper sheets 40 and the second busbar 20 may be filled with a second medium M2 having a second dielectric constant ∈ 2. The first medium M1 and the second medium M2 may be any insulating medium having a dielectric constant, such as an insulating paste, ceramic, glass glaze, polystyrene, or other plastic film. Filling a first medium M1 with a first dielectric constant epsilon 1 in the overlapping part of the first copper sheet 30 and the first busbar 10 to construct a first distributed capacitor between the first copper sheet 30 and the first busbar 10; and filling a second medium M2 with a second dielectric constant epsilon 2 in the overlapped part of the second copper sheets 40 and the second busbar 20 to construct a second distribution capacitor between the second copper sheets 40 and the second busbar 20. The embodiment of the utility model provides a suitable first medium M1 that has first dielectric constant ε 1 and second medium M2 that has second dielectric constant ε 2 can be selected according to actual need's distributed capacitance's appearance value size.

Alternatively, the first medium M1 and the second medium M2 may include an insulating paste; the first permittivity ∈ 1 and the second permittivity ∈ 2 may be 10. Preferably, the embodiment of the utility model provides a technical scheme, first medium M1 is the same with the material of second medium M2, all chooses the insulating cement as insulating medium, and first dielectric constant ε 1 and second dielectric constant ε 2 all select 10 in addition to reach better common mode filtering effect.

Fig. 4 is an effect diagram of implementing common mode filtering by using distributed capacitors according to an embodiment of the present invention. Referring to fig. 4, the abscissa is frequency, and the unit is MHz, and the ordinate is field intensity voltage signal, and the unit is dBuV, can see from the picture that in the frequency range department more than 9MHz, the field intensity voltage signal intensity that adopts the distributed capacitance filtering obviously reduces than the field intensity voltage signal that does not adopt the distributed capacitance filtering, explains and adopts the utility model discloses a distributed capacitance scheme has reached fine common mode filtering effect, has improved electromagnetic interference EMI's level.

Optionally, as shown in fig. 1 and fig. 2, the motor inverter 1 may further include a dc bus capacitor 50; the first busbar 10 may be provided with a first connection point P1; the second busbar 20 may be provided with a second connection point P2; the first connection point P1 and the second connection point P2 are used to connect the dc bus capacitor 50. The embodiment of the utility model provides a technical scheme, first female row 10 and the female 20 adoption stromatolite setting of arranging of second, and set up DC bus electric capacity 50 in the female one side of arranging 20 and keeping away from first female row 10 of second, the first end of arranging 20 at first female row 10 and the first end of second is provided with first tie point P1 and second tie point P2 respectively, first tie point P1 and second tie point P2 are used for first female 10 of arranging to be connected with DC bus electric capacity 50 electricity respectively, and female 20 of arranging of second is connected with DC bus electric capacity 50 electricity.

Optionally, as shown in fig. 2, the first busbar 10 may be provided with a first via a 1; the second busbar 20 may be provided with a second via a 2; the first via a1 and the second via a2 are used for connecting a dc input power source (not shown in the figure). The embodiment of the utility model provides a technical scheme, the second end of arranging 20 at the second end of first female row 10 and second is provided with first via hole A1 and second via hole A2 respectively, and first via hole A1 and second via hole A2 are used for first female row 10 to be connected with direct current input power supply electricity respectively to and female row 20 of second is connected with direct current input power supply electricity.

Optionally, with continued reference to fig. 2, the motor inverter 1 may further include a power module (not shown in the figures); the power module may include a switching device (not shown in the drawings); the first busbar 10 may be provided with a third connection point P3; the second busbar 20 may be provided with a fourth connection point P4; the third connection point P3 and the fourth connection point P4 are used to connect the switching device. The embodiment of the utility model provides a technical scheme, the second end of arranging 20 at first female second end of arranging 10 and second is provided with third tie point P3 and fourth tie point P4 respectively, and third tie point P3 and fourth tie point P4 are used for first female 10 of arranging to be connected with power module's switching device electricity respectively to and female 20 of arranging of second is connected with power module's switching device electricity.

Alternatively, the switching device may comprise an insulated gate bipolar transistor, or a metal-oxide semiconductor field effect transistor, or an integrated gate commutated thyristor. Specifically, an Insulated Gate Bipolar Transistor (IGBT) is a composite fully-controlled voltage-driven power semiconductor device composed of a Bipolar Transistor BJT and an Insulated Gate field effect Transistor MOS, and has the advantages of high input impedance and low on-state voltage drop. A Metal-Oxide-Semiconductor Field Effect Transistor (MOSFET), which is a Field Effect Transistor FET widely used in analog circuits and digital circuits, can be divided into two types, i.e., N-type and P-type, according to the difference in polarity of working carriers, and is generally called NMOSFET and PMOSFET, and other types include NMOS and PMOS for short. An Integrated Gate-Commutated Thyristor (IGCT), i.e., a Gate-Commutated Thyristor, has the characteristics of large capacity, high switching speed and simple circuit structure. The embodiment of the utility model provides a technical scheme can be applicable to multiple switching device's power module, has wider application. Preferably, according to the technical scheme provided by the embodiment of the present invention, the switching device adopted by the power module is an insulated gate bipolar transistor.

In the embodiment of the utility model, through drawing forth first copper sheet and second copper sheet from motor inverter's casing, set up first copper sheet in the first mother row keep away from one side of second mother row, the second copper sheet sets up in the second mother row keep away from one side of first mother row, adopt the electromagnetic compatibility forward design promptly, set up first copper sheet and second copper sheet drawn forth from inverter casing in first mother row and second mother row both sides, construct the distributed capacitance between first mother row and the first copper sheet, and the distributed capacitance between second mother row and the second copper sheet, when realizing common mode filtering's effect, when improving the electromagnetic interference EMI grade, still saved installation space; in addition, the constructed distributed capacitance is almost pure capacitive and is not limited by parasitic inductance, so that the applicable frequency range is wider.

It should be noted that the foregoing is only a preferred embodiment of the present invention and the technical principles applied. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail with reference to the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the scope of the present invention.

Claims (10)

1. The motor inverter is characterized by comprising a first busbar, a second busbar, a first copper sheet and a second copper sheet, wherein the first copper sheet and the second copper sheet are led out from a shell of the motor inverter;

the first busbar and the second busbar are arranged in a laminated manner;

the first copper sheet is arranged on one side of the first busbar, which is far away from the second busbar; in a first plane, the first copper sheet is at least partially overlapped with the first busbar;

the second copper sheet is arranged on one side of the second busbar, which is far away from the first busbar; and in a second plane parallel to the first plane, the first copper sheet is at least partially overlapped with the first busbar.

2. The motor inverter of claim 1, wherein the first copper sheet completely overlaps the first busbar in a plane parallel to the first plane; and in a plane parallel to the second plane, the second copper sheet is completely overlapped with the second busbar.

3. The motor inverter of claim 1, wherein the first copper sheet is a first distance from the first bus bar; the second copper sheet is away from the second busbar by a second distance; the first distance and the second distance are greater than zero.

4. The motor inverter of claim 3, wherein the first distance is D1 and the second distance is D2, wherein 0.8mm ≦ D1 ≦ 1.2 mm; d2 is not less than 0.8mm and not more than 1.2 mm.

5. The motor inverter according to claim 1, wherein an overlapping portion of the first copper sheet and the first bus bar is filled with a first medium having a first dielectric constant; and the overlapping part of the second copper sheet and the second busbar is filled with a second medium with a second dielectric constant.

6. The motor inverter of claim 5, wherein the first and second dielectrics comprise an insulating paste;

the first and second dielectric constants are 10.

7. The motor inverter of claim 1, further comprising a dc bus capacitor;

the first busbar is provided with a first connecting point; the second busbar is provided with a second connecting point; the first connection point and the second connection point are used for connecting the direct current bus capacitor.

8. The motor inverter according to claim 1, wherein the first busbar is provided with a first via hole; the second busbar is provided with a second through hole; the first via hole and the second via hole are used for connecting a direct current input power supply.

9. The motor inverter of claim 1, further comprising a power module; the power module includes a switching device;

the first busbar is provided with a third connecting point; the second busbar is provided with a fourth connecting point; the third connection point and the fourth connection point are used for connecting the switching device.

10. The motor inverter of claim 9, wherein the switching device comprises an insulated gate bipolar transistor, or a metal-oxide semiconductor field effect transistor, or an integrated gate commutated thyristor.

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