CN217363035U

CN217363035U - EMC filter

Info

Publication number: CN217363035U
Application number: CN202221223221.1U
Authority: CN
Inventors: 夏雨昕
Original assignee: Leadrive Technology Shanghai Co Ltd
Current assignee: Leadrive Technology Shanghai Co Ltd
Priority date: 2022-05-19
Filing date: 2022-05-19
Publication date: 2022-09-02
Anticipated expiration: 2032-05-19

Abstract

The utility model provides an EMC filter, which comprises a PCB assembly and a capacitor assembly arranged on the PCB assembly, wherein the PCB assembly comprises a PCB upper surface and a PCB lower surface, and a middle gap is formed between the PCB upper surface and the PCB lower surface; at least one first capacitor in the capacitor bank is fixedly arranged on the upper surface of the PCB; at least one second capacitor in the capacitor bank is fixedly arranged on the lower surface of the PCB; the EMC filter further includes: the first copper bar is attached to a first inner surface of the upper surface of the PCB, which forms a middle gap; the second copper bar is attached to a second inner surface of the lower surface of the PCB, wherein a middle gap is formed on the second inner surface; and the first copper bar and the second copper bar are mutually separated. After the technical scheme is adopted, the DC copper bar, the PCB and the EMC magnetic ring used as the inductor can be integrated into a whole.

Description

EMC filter

Technical Field

The utility model relates to a semiconductor equipment field especially relates to an EMC wave filter.

Background

The special input EMC filter for the frequency converter mainly comprises (L) filter inductance and (C) filter capacitance. The special input EMC filter for the frequency converter works by utilizing the principle of impedance mismatch; in general, the default power source terminal of a common frequency converter is low-impedance, so the input terminal of the input filter of the frequency converter is high-impedance; on the load side, the default is high impedance, and the output end of the corresponding frequency converter input filter is low impedance. By using this principle, an effective suppression of the generated higher harmonics is achieved for the frequency tunable EMC filter combination.

When a general EMC filter is designed, inductors are usually arranged on the same side of a copper bar in a vertically symmetrical mode relative to the copper bar, and capacitors are arranged on the same side of the copper bar, so that space waste on a space Z axis (or the axial direction of the whole EMC filter) is easily caused, and the finally formed EMC filter is huge in structure and does not accord with an integrated design principle.

Therefore, a new EMC filter structure is needed, which can integrate the PCB board and the copper bar to reduce the equivalent series inductance (ESL) of the capacitor.

SUMMERY OF THE UTILITY MODEL

In order to overcome the technical defect, the utility model aims to provide an EMC filter can be with DC copper bar, PCB board and as the EMC magnetic ring integration as the inductance integrative.

The utility model discloses an EMC filter, which comprises a PCB group and a capacitor group arranged on the PCB group,

the PCB group comprises an upper surface of the PCB and a lower surface of the PCB, and a middle gap is formed between the upper surface of the PCB and the lower surface of the PCB;

at least one first capacitor in the capacitor bank is fixedly arranged on the upper surface of the PCB;

at least one second capacitor in the capacitor bank is fixedly arranged on the lower surface of the PCB;

the EMC filter further includes:

the first copper bar is attached to a first inner surface of the upper surface of the PCB, which forms a middle gap;

the second copper bar is attached to a second inner surface of the lower surface of the PCB, which forms a middle gap;

and the first copper bar and the second copper bar are mutually separated.

Preferably, the upper surface of the PCB and the lower surface of the PCB are arranged in parallel;

the upper surface of the PCB is provided with a first through hole and a second through hole which axially penetrate through the upper surface of the PCB;

the lower surface of the PCB is provided with a third through hole and a fourth through hole which axially penetrate through the lower surface of the PCB;

wherein

The first through hole and the third through hole are communicated with each other along the axial direction of the upper surface of the PCB and the lower surface of the PCB;

the second through hole and the fourth through hole are mutually communicated along the axial direction of the upper surface of the PCB and the lower surface of the PCB;

the EMC filter further comprises an EMC magnetic ring which penetrates through the first through hole, the second through hole, the third through hole and the fourth through hole to be sleeved on the PCB group.

Preferably, the EMC magnetic ring includes a first C-shaped magnetic ring unit and a second C-shaped magnetic ring unit;

the first C-shaped magnetic ring unit comprises a first end and a second end which are respectively inserted into the first through hole and the second through hole;

the second C-shaped magnetic ring unit comprises a third end and a fourth end which are respectively inserted into the third through hole and the fourth through hole;

the first end is jointed with the third end, and the second end is jointed with the fourth end, so that the EMC magnetic ring is sleeved on the PCB group.

Preferably, the first end is bonded with the third end, and the second end is bonded with the fourth end;

the diameters of the first through hole and the second through hole are equivalent to the diameters of the first end and the second end;

the aperture of the third through hole and the fourth through hole is equivalent to the diameter of the third end and the fourth end.

Preferably, the inner surface of the first C-shaped magnetic ring unit close to the upper surface of the PCB is spaced from the upper surface of the PCB;

the second C-shaped magnetic ring unit is close to the inner surface of the lower surface of the PCB and is separated from the lower surface of the PCB.

Preferably, the upper surface of the PCB is provided with a first capacitor mounting through hole and a second capacitor mounting through hole;

a third capacitor mounting through hole and a fourth capacitor mounting through hole are formed in the lower surface of the PCB;

the first capacitor is welded with the first capacitor mounting through hole or the second capacitor mounting through hole to be electrically connected with the upper surface of the PCB;

the second capacitor is welded with the third capacitor mounting through hole or the fourth capacitor mounting through hole to be electrically connected with the lower surface of the PCB.

Preferably, the first capacitor mounting via hole and the second capacitor mounting via hole are arranged in the projection range of the first copper bar on the upper surface of the PCB;

the third capacitor installation via hole and the fourth capacitor installation via hole are arranged in the projection range of the second copper bar on the lower surface of the PCB.

Preferably, a fifth through hole and a sixth through hole which penetrate through the upper surface of the PCB along the axial direction are formed in the upper surface of the PCB;

a seventh through hole and an eighth through hole which axially penetrate through the lower surface of the PCB are formed in the lower surface of the PCB;

the EMC filter further comprises a first grounding bolt and a second grounding bolt, wherein the first grounding bolt penetrates through the fifth through hole and the sixth through hole to fixedly connect the upper surface of the PCB and the lower surface of the PCB, and the second grounding bolt penetrates through the seventh through hole and the eighth through hole to fixedly connect the upper surface of the PCB and the lower surface of the PCB.

After the technical scheme is adopted, compared with the prior art, the method has the following beneficial effects:

1, providing a welding port for a capacitor on the PCB without additional design connection;

2. the EMC magnetic ring used as the inductor is similar to the upper plate of the transformer, is inserted and buckled on the PCB up and down, and forms a common mode inductor with the copper bar, so that the size of the EMC filter is reduced;

3. the large-area copper bar and the short pin compared with the prior art are designed, so that the reduction of the ESL (electric field shaping) of the capacitor is facilitated;

and 4, the PCB forms insulation between PN, and meanwhile, the overlapping area is large, the loop is small, and the space noise is not easily coupled.

Drawings

Fig. 1 is a side view of an EMC filter in accordance with a preferred embodiment of the present invention;

fig. 2 is a perspective view of an EMC filter according to a preferred embodiment of the present invention;

fig. 3 is a perspective view of an EMC filter according to a preferred embodiment of the present invention.

Reference numerals:

100-an EMC filter;

110-upper surface of PCB board, 111-first through hole, 112-second through hole, 113-first capacitor mounting via hole, 114-second capacitor mounting via hole, 115-fifth through hole, 116-sixth through hole;

120-lower surface of PCB board, 121-third through hole, 122-fourth through hole, 123-third capacitor mounting through hole, 124-fourth capacitor mounting through hole, 125-seventh through hole, 126-eighth through hole;

130-a first capacitance;

140-a second capacitance;

150-a first copper bar;

160-a second copper bar;

170-EMC magnetic ring, 171-first C-shaped magnetic ring unit, 172-first end, 173-second end, 174-second C-shaped magnetic ring unit, 175-third end, 176-fourth end;

180-a first earth bolt;

190-second earth bolt.

Detailed Description

The advantages of the present invention will be further explained with reference to the accompanying drawings and specific embodiments.

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. The following description refers to the accompanying drawings in which the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the exemplary embodiments below are not intended to represent all implementations consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present disclosure, as detailed in the appended claims.

The terminology used in the present disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used in this disclosure and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

It is to be understood that although the terms first, second, third, etc. may be used herein to describe various information, such information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present disclosure. The word "if" as used herein may be interpreted as "at … …" or "when … …" or "in response to a determination", depending on the context.

In the description of the present invention, it is to be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships illustrated in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.

In the description of the present invention, unless otherwise specified and limited, it is to be noted that the terms "mounted," "connected" and "connected" are to be interpreted broadly, and may be, for example, a mechanical connection or an electrical connection, a communication between two elements, a direct connection, or an indirect connection through an intermediate medium, and those skilled in the art may understand the specific meanings of the above terms according to specific situations.

In the following description, suffixes such as "module", "part", or "unit" used to indicate elements are used only for the convenience of description of the present invention, and have no specific meaning in itself. Thus, "module" and "component" may be used in a mixture.

Referring to fig. 1, fig. 2 and fig. 3, in order to meet the structural schematic diagram of the EMC filter 100 in a preferred embodiment of the present invention, in this embodiment, the EMC filter 100 includes a PCB board group and a capacitor group disposed on the PCB board group, and the design of the PCB board group is adopted, which firstly increases the number of capacitors that can be set, and secondly provides space for the subsequent stacked design. Specifically, the PCB panel assembly includes a PCB upper surface 110 and a PCB lower surface 120, the PCB upper surface 110 and the PCB lower surface 120 are contacted and spliced with each other to form a whole PCB (or are integrally formed), a hollow region between the PCB upper surface 110 and the PCB lower surface 120 forms a middle gap, and the middle gap can be used as an insulation space between PN of the capacitor, thereby avoiding the occurrence of coupling space noise.

Under the design of the PCB group, the configuration scheme of the capacitor group is as follows: the capacitor groups are 2 groups, the first group is formed by at least one first capacitor 130, the second group is formed by at least one second capacitor 140, and the number of the first capacitors 130 and the second capacitors 140 may be the same. First capacitor 130 is mounted on PCB upper surface 110, and second capacitor 140 is mounted on PCB lower surface 120, that is, the middle gap is located inside PCB upper surface 110 and PCB lower surface 120, and first capacitor 130 and second capacitor 140 are located outside PCB upper surface 110 and PCB lower surface 120, so that the axial (Z-direction) space of the PCB board set can be fully utilized (i.e. the wasted space in the prior art is mutually utilized).

In addition, the EMC filter 100 further includes a first copper bar 150 and a second copper bar 160 respectively attached to the first inner surface of the PCB upper surface 110 and the second inner surface of the PCB lower surface 120 forming the middle gap, and the first copper bar 150 and the second copper bar 160 are separated from each other to form an electrical isolation design. Under this design, the first copper bar 150 and the second copper bar 160 can have large size along the transverse direction to bear large current (or all current flows through the PCB board set), and at the same time, further utilize the space of the middle gap to reduce the size.

It can be understood that the first copper bar 150 and the second copper bar 160 can be one layer or multiple layers, that is, the first copper bar 150 and the second copper bar 160 can be combined, or the first copper bar 150 can be split into two layers, which together form a whole copper bar.

In a preferred embodiment, the upper surface 110 of the PCB and the lower surface 120 of the PCB are disposed in parallel, so that the effect of preventing the generation of the coupling space noise is uniform at any position of the middle gap. In addition, the upper surface 110 of the PCB is provided with a first through hole 111 and a second through hole 112 axially penetrating through the upper surface 110 of the PCB; a third through hole 121 and a fourth through hole 122 which axially penetrate through the lower surface 120 of the PCB are formed in the lower surface 120 of the PCB; wherein the first through hole 111 and the third through hole 121 communicate with each other in the axial direction of the PCB upper surface 110 and the PCB lower surface 120, or more preferably, the first through hole 111 and the third through hole 121 are sized and aligned with each other. The second through hole 112 and the fourth through hole 122 are communicated with each other along the axial direction of the PCB upper surface 110 and the PCB lower surface 120, or more preferably, the second through hole 112 and the fourth through hole 122 are sized and aligned with each other. Meanwhile, the EMC filter 100 further includes an EMC magnetic ring 170, and the EMC magnetic ring 170 serves as an inductor of the EMC filter 100, which penetrates the first through hole 111, the second through hole 112, the third through hole 121, and the fourth through hole 122 to be fitted over the PCB board group. In this configuration, the EMC magnetic ring 170 still has an up-and-down symmetrical shape (the "boundary" in this embodiment may be represented by the PCB top surface 110 or the PCB bottom surface 120, or a central layer of the middle gap) around the PCB.

Further, the EMC magnetic ring 170 includes a first C-shaped magnetic ring unit 171 and a second C-shaped magnetic ring unit 174, which are spliced together to form a ring shape, and form a common mode inductor with the copper bars. Specifically, the first C-shaped magnetic ring unit 171 includes a first end 172 and a second end 173, and a magnetic ring upper surface connecting the first end 172 and the second end 173, the first end 172 and the second end 173 are respectively inserted into the first through hole 111 and the second through hole 112, and the position to which the free end extends may be a central layer of the middle gap. The second C-shaped magnetic ring unit 174 includes a third end 175 and a fourth end 176, and a lower surface of the magnetic ring connecting the third end 175 and the fourth end 176, the third end 175 and the fourth end 176 are respectively inserted into the third through hole 121 and the fourth through hole 122, and the position to which the free end extends may also be a central layer of the middle gap. In the extended position, the first end 172 and the third end 175 are engaged and the second end 173 and the fourth end 176 are engaged such that the EMC magnet ring 170 is sleeved over the PCB board assembly. The first end 172 and the third end 175, and the second end 173 and the fourth end 176 can be connected by plugging, bonding, etc., and the first through hole 111 and the second through hole 112 have a diameter corresponding to the diameter of the first end 172 and the second end 173; the third through hole 121 and the fourth through hole 122 have the same diameter as the third end 175 and the fourth end 176, so that the whole EMC magnetic ring 170 is symmetrical to each other by dividing into "borders", and the same filtering effect is achieved at different positions of the PCB panel group.

Meanwhile, when the EMC magnetic ring 170 is installed, it is preferable to note that the inner surface of the first C-shaped magnetic ring unit 171 close to the PCB upper surface 110 is separated from the PCB upper surface 110, and on the other side, the inner surface of the second C-shaped magnetic ring unit 174 close to the PCB lower surface 120 is separated from the PCB lower surface 120, so that the EMC magnetic ring 170 is separated from the PCB upper surface 110 and the PCB lower surface 120, and the EMC magnetic ring 170 is fixed in the EMC filter 100 by engaging with the first through hole 111, the second through hole 112, the third through hole 121, and the fourth through hole 122 in the area where no circuit or line is disposed.

In a preferred embodiment, in order to realize the fast electrical connection between the first capacitor 130 and the PCB upper surface 110 and the fast electrical connection between the second capacitor 140 and the PCB lower surface 120, the PCB upper surface 110 is provided with a first capacitor 130 mounting via 113 and a second capacitor 140 mounting via 114; the PCB lower surface 120 is formed with a third capacitor mounting via 123 and a fourth capacitor mounting via 124, the first capacitor 130 can be directly soldered to the first capacitor 130 mounting via 113 or the second capacitor 140 mounting via 114 to be electrically connected to the PCB upper surface 110, or the pin of the first capacitor 130 is electrically connected to the first capacitor 130 mounting via 113 and the second capacitor 140 mounting via 114 via a circuit on the PCB upper surface 110. The first capacitor 130 mounting via hole 113 and the second capacitor 140 mounting via hole 114 function to fixedly mount the first capacitor 130, and also transmit the signal of the first capacitor 130 to the PCB upper surface 110, and if necessary, the first copper bar 150 can be reused to electrically extend to other positions of the PCB upper surface 110. On the other hand, the second capacitor 140 is soldered to the third capacitor mounting via 123 or the fourth capacitor mounting via 124 to be electrically connected to the lower PCB panel surface 120, or the pins of the second capacitor 140 are electrically connected to the third capacitor mounting via 123 and the fourth capacitor mounting via 124 through the wiring on the lower PCB panel surface 120. Above-mentioned third electric capacity installation via hole 123 and fourth electric capacity installation via hole 124 play the effect with second electric capacity 140 fixed mounting promptly, can also with second electric capacity 140's signal transmission to PCB board lower surface 120 on, need, can recycle second copper bar 160 electricity and extend to other positions of PCB board lower surface 120. With the above configuration, the capacitor circuit is very short, and the filtering effect is improved.

In order to realize the signal transmission, the first capacitor 130 mounting via hole 113 and the second capacitor 140 mounting via hole 114 are disposed within the projection range of the first copper bar 150 on the PCB upper surface 110; the third capacitor mounting via 123 and the fourth capacitor mounting via 124 are disposed within a projection range of the second copper bar 160 on the lower surface 120 of the PCB.

In order to complete the grounding installation of the EMC filter 100, the PCB top surface 110 is provided with a fifth through hole 115 and a sixth through hole 116 axially penetrating through the PCB top surface 110, and the PCB bottom surface 120 is provided with a seventh through hole 125 and an eighth through hole 126 axially penetrating through the PCB bottom surface 120. The positions of the fifth through hole 115 and the sixth through hole 116 may be outside the shadow area of the PCB upper surface 110 of the first capacitor 130, or may be directly disposed at the edge positions or the four corner positions of the PCB upper surface 110 and the PCB lower surface 120. Similarly, the positions of the seventh through hole 125 and the eighth through hole 126 may be outside the shadow area of the PCB lower surface 120 of the second capacitor 140, or directly disposed at the edge positions or the four corner positions of the PCB upper surface 110 and the PCB lower surface 120. Correspondingly, the EMC filter 100 further includes a first ground bolt 180 and a second ground bolt 190, the first ground bolt 180 penetrates the fifth through hole 115 and the sixth through hole 116 to fixedly connect the PCB upper surface 110 and the PCB lower surface 120, and the second ground bolt 190 penetrates the seventh through hole 125 and the eighth through hole 126 to fixedly connect the PCB upper surface 110 and the PCB lower surface 120. The first and

second ground bolts

180 and 190 serve to fix the PCB top surface 110 and the PCB bottom surface 120 to each other, and the first and

second ground bolts

180 and 190 may extend to the chassis where the EMC filter 100 of the present invention is disposed, so as to lead out undesired electrical factors such as static electricity to ground.

In any of the above embodiments, if the PCB panel group is configured to have more than one pair, for example, a plurality of layers, the number of copper bars may also be correspondingly increased, for example, 6 layers above and below, the upper three layers of copper bars may be used to transmit positive current, the lower three layers of copper bars may be used to transmit negative current, and the capacitor group and the ground bolt may be adapted to be modified or not modified, and adjusted according to actual conditions.

It should be noted that the embodiments of the present invention have better practicability and are not intended to limit the present invention in any way, and any person skilled in the art may change or modify the technical contents disclosed above to equivalent effective embodiments, but all the modifications or equivalent changes and modifications made to the above embodiments according to the technical spirit of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. An EMC filter comprises a PCB group and a capacitor group arranged on the PCB group, and is characterized in that the PCB group comprises an upper surface of a PCB and a lower surface of the PCB, and a middle gap is formed between the upper surface of the PCB and the lower surface of the PCB;

at least one first capacitor in the capacitor bank is fixedly mounted on the upper surface of the PCB;

at least one second capacitor in the capacitor bank is fixedly mounted on the lower surface of the PCB;

the EMC filter further includes:

the first copper bar is attached to a first inner surface of the upper surface of the PCB board, which forms the middle gap;

the second copper bar is attached to a second inner surface of the lower surface of the PCB, which forms the middle gap;

and the first copper bar and the second copper bar are mutually separated.

2. The EMC filter of claim 1,

the upper surface of the PCB and the lower surface of the PCB are arranged in parallel;

a first through hole and a second through hole which axially penetrate through the upper surface of the PCB are formed in the upper surface of the PCB;

a third through hole and a fourth through hole which axially penetrate through the lower surface of the PCB are formed in the lower surface of the PCB; wherein

The first through hole and the third through hole are mutually communicated along the axial direction of the upper surface of the PCB and the lower surface of the PCB;

the EMC filter further comprises an EMC magnetic ring, and the EMC magnetic ring penetrates through the first through hole, the second through hole, the third through hole and the fourth through hole to be sleeved on the PCB plate group.

3. The EMC filter of claim 2,

the EMC magnetic ring comprises a first C-shaped magnetic ring unit and a second C-shaped magnetic ring unit;

the first end and the third end are jointed, and the second end and the fourth end are jointed, so that the EMC magnetic ring is sleeved on the PCB group.

4. The EMC filter of claim 3,

the first end is bonded with the third end, and the second end is bonded with the fourth end;

the diameters of the third through hole and the fourth through hole are equivalent to the diameters of the third end and the fourth end.

5. The EMC filter of claim 4,

the inner surface of the first C-shaped magnetic ring unit close to the upper surface of the PCB is separated from the upper surface of the PCB;

6. The EMC filter of claim 2,

a first capacitor mounting through hole and a second capacitor mounting through hole are formed in the upper surface of the PCB;

the second capacitor and the third capacitor mounting through hole or the fourth capacitor mounting through hole are welded to be electrically connected with the lower surface of the PCB.

7. The EMC filter of claim 6,

the first capacitor mounting through hole and the second capacitor mounting through hole are arranged in the projection range of the first copper bar on the upper surface of the PCB;

the third capacitor mounting via hole and the fourth capacitor mounting via hole are arranged in the second copper bar in the projection range of the lower surface of the PCB.

8. The EMC filter of claim 1,

a fifth through hole and a sixth through hole which axially penetrate through the upper surface of the PCB are formed in the upper surface of the PCB;

the EMC filter still includes first earth bolt and second earth bolt, first earth bolt penetrates fifth through-hole, sixth through-hole are with fixed connection PCB board upper surface and PCB board lower surface, the second earth bolt penetrates seventh through-hole, eighth through-hole are with fixed connection PCB board upper surface and PCB board lower surface.