CN110401341A - EMV filter - Google Patents

Abstract

The invention relates to an EMV filter (1) having a plurality of filter parts comprising at least a common mode choke (10), an intermediate circuit capacitor (21), a Y capacitor (20) and an X capacitor ( 40) wherein the EMV filter is formed such that each filter component can be positioned in such a way that the filter components contribute damping to the EMV filter (1) in addition to their respective main function.

Description

EMV filter

technical field

The present invention relates to an EMV filter.

Background technique

EMV filters (EMV=Electromagnetic Compatibility) are used in the power electronics in vehicles in order to ensure that the vehicle electrical system is as free from disturbances as possible. EMV filters can be used not only on the DC (DC=direct current) side of power electronics, but also on the AC (AC=alternating current) side. In the case of an inverter that converts the DC energy of the battery to AC energy on the motor, an EMV filter is incorporated on the DC high voltage interface in order to reduce the propagation of electromagnetic interference in the direction of the battery.

The EMC filters used hitherto are not optimal for the utilization of installation space, since the filter components are not inserted optimally into the installation space and thus reduce the damping effect of the filter.

Contents of the invention

It is therefore the object of the present invention to provide an improved EMC filter which has an improved utilization of installation space. This object is solved according to the invention by the features of the independent claims. Advantageous refinements are the subject matter of the subclaims.

There is provided an EMV filter comprising a plurality of filter parts including at least a common mode choke coil, an intermediate circuit capacitor, a Y capacitor and an X capacitor, wherein the EMV filter is formed such that each filter part can be are positioned in such a way that each of the filter components contributes damping to the EMV filter in addition to its respective main function.

Furthermore, in one specific embodiment, the EMC filter has a housing in which at least an intermediate circuit capacitor is arranged, wherein likewise at least a common mode choke and a Y capacitor are arranged in the housing. Space can be saved by placing multiple filter components in the housing.

In one embodiment, a fastening portion is provided on the housing, which simultaneously serves as a choke fastening portion for fastening the common mode choke and as a ground for the Y capacitor. By fastening the choke coil on the housing, the fastening part is also used as the ground part of the Y capacitor, so as to save space.

In one embodiment, the choke fastening is formed in such a way that the X capacitor can be fastened on the side of the DC current plug. Therefore, the line length is shortened and interference is reduced.

In one embodiment, the Y capacitor is arranged adjacent to the semiconductor components arranged on the circuit board. Therefore, the de-interference effect of the Y capacitor can be better utilized.

In one embodiment, a DC current sensor is provided as an additional filter component, which is arranged between the common mode choke and the X capacitor. Thus, parasitic effects can be used and at the same time the damping effect is enhanced.

In one embodiment, a push-pull choke is also provided as an additional filter component, which is positioned between the common mode choke and the X capacitor and determined depending on the required damping of the provided application Specification.

In one embodiment, a separate cooling unit is provided for each of the filter components. As a result, interfaces can be reduced and the cooling needs of components can be considered individually.

In one embodiment, the EMV filter is a component of a drive inverter for the automotive sector.

Further features and advantages of the invention emerge from the following description of embodiments of the invention in conjunction with the drawings showing details according to the invention and from the claims. In variants of the invention, the individual features can be realized individually or in any desired combination.

Description of drawings

Preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. in:

Figure 1 shows a view of an inverter with an EMV filter according to an embodiment of the present invention;

2 shows a view of a fastening portion of a common mode choke coil according to an embodiment of the present invention;

Figure 3 shows a view for the connection of X capacitors on a common mode choke according to an embodiment of the invention;

Figure 4 shows another view of the connection on the common mode choke for X capacitors according to an embodiment of the present invention;

Figure 5 shows a view of the arrangement of further components according to an embodiment of the invention;

In the following detailed description, the same elements or functions have the same reference numerals.

Detailed ways

The core of the invention is to reduce the installation space for arranging the filter components in the EMC filter and thereby optimize the filter damping.

1 to 5 show different views of the concept according to the invention of the arrangement of the filter components of an EMV filter 1 comprising a choke 10 generally implemented as a common mode choke and comprising a Components 20 of intermediate circuit capacitor 21 and Y capacitor 22 and X capacitor 40 . Furthermore, the semiconductor component 30 is provided as well as the choke fastening 11 and the connection 23 for fastening and the connection for electrically contacting the DC current plug 3 . It can also be seen that the connection to the DC current plug 3 is arranged in the vicinity of the choke or common mode choke 10 and the X-capacitor 40 . Such an EMC filter 1 is advantageously used in drive inverters used in the automotive sector.

FIG. 2 shows a detail of a bottom view of the view shown in FIG. 1 . It can be seen here that due to the arrangement according to the invention it is possible for the choke coils 10 to share the housing of the intermediate circuit capacitor 21 . The Y capacitor 22 is located here in the same housing as the intermediate circuit capacitor 21 . The fastening 23 , which can be embodied as a screw connection, can be used simultaneously for fastening the inductor 10 and the grounding of the Y-capacitor. Additionally, the choke fastening portion 11 can be formed in such a way that the X capacitor 40 can be mounted on the side of the DC current plug 3 . This is illustrated from different perspectives in FIGS. 3 and 4 . In more detail, the respective electrical coupling locations may be formed spaced apart from each other such that the X-capacitor 40 is located in the space between them, as shown in FIG. 4 .

The core of the invention is that the different filter components 10, 20, 40 are optimally placed by integration inside the drive inverter in order not only to fulfill their main task but also to provide improved (filter) damping, and in This still makes optimum use of the installation space.

The most important filter components in such a drive inverter are the common mode choke coil 10 , the Y capacitor 20 and the X capacitor 40 .

The common mode choke 10 or current-compensated filter choke or CMC for short (common mode choke in English) is used for damping interference emissions. The X and Y capacitors are used as noise suppression capacitors, for example to eliminate leakage currents.

By positioning the Y capacitor 22 close to the semiconductor components 30 which are usually arranged on the circuit board 7 and which are the most important sources of interference with regard to electromagnetic compatibility, the interference damping effect of the Y capacitor can be better utilized. In principle, interference must be eliminated as close to the source as possible to avoid further propagation. With the proposed concept of integration, the path between Y capacitor 22 and semiconductor 30 is kept as short as possible. Thus, the inductance L between the power module or semiconductor 30 and the Y capacitor 22 is minimized, thereby ensuring that the impedance for the path is small. In addition, the installation space can also be better utilized, since at least to a large extent it is not necessary to recheck the EMC interfaces or long connecting lines.

The distribution of the filter components 10 , 20 , 40 in order to enable them to achieve a better damping action provides installation space for other components which, in addition to their main function, can likewise contribute to damping disturbances. An example of this is a DC current sensor 50 as shown in FIG. 5 . Parasitic effects are exploited and damping is enhanced by placing the DC current sensor 50 between the common mode choke 10 and the X capacitor 40 . However, in this example the X capacitors 40 no longer share the choke fastening portion 11 of the common mode choke 10 as shown in FIGS. behind the current sensor 50.

An additional advantage of the distributedly arranged filter components 10 , 20 , 40 is that different cooling capacities via corresponding cooling units can be achieved for the filter components 10 , 20 , 40 as a function of their respective losses and their properties. . The cooling unit can here be individually adapted to the component to be cooled, that is to say not only in terms of its shape but also in terms of cooling performance.

A further possibility for improving the EMC filter 1 consists in positioning additional filter components such as push-pull chokes in such a way that the damping required or required for the respective application can be achieved. This can also be achieved in that, due to the positioning of the other filter components 10 , 20 , 40 , installation space is free at suitable locations.

Through the concept of the EMV filter for the drive inverter, a reduction in the installation space for filtering is achieved. Furthermore, optimum utilization of the filter components and thus an additional damping effect via the filter components is ensured.

The exact positioning of each of the individual components here depends on the respective application and the components used.

List of reference signs

1 EMV filter

10 Common Mode Chokes

11 Choke coil fastening part

23 screw contacts

3 Connection part of DC current plug

20 Intermediate circuit capacitors with Y capacitors

22 Y capacitor

30 Semiconductor components

40 X Capacitors

50 DC current sensor

Claims (9)

1. a kind of EMV filter (1), with multiple filter parts, the filter part includes at least common mode choke (10), intermediate circuit capacitor (21), Y capacitor (20) and X capacitor (40), wherein the EMV filter is formed, so that Each filter part can be positioned as follows, that is, make the filter part other than its respective major function Also apply the effect of damping to the EMV filter (1).

2. EMV filter (1) according to claim 1, the EMV filter also have shell, in the shell extremely It is disposed with the intermediate circuit capacitor (21) less, wherein the common mode choke is equally at least disposed in the shell (10) and the Y capacitor (22).

3. EMV filter (1) according to claim 1 or 2, wherein it is provided with fastening part on the housing, it is described tight Gu portion is used as the choke coil fastening part (11) for fastening the common mode choke (10) simultaneously and is used as the Y capacitor (22) grounding parts.

4. EMV filter (1) according to claim 3, wherein the choke coil fastening part (11) is formed, so that the X Capacitor (40) can be fastened on the side of DC electric current plug device (3).

5. EMV filter (1) according to any one of the preceding claims, wherein the Y capacitor (21) be arranged in Semiconductor component (30) on circuit board (7) is adjacently positioned.

6. EMV filter (1) according to any one of the preceding claims, in addition, being additionally provided with DC electric current sensor (50) it is used as additional filter part, the DC electric current sensor arrangement is in the common mode choke (10) and the X capacitor Between device (40).

7. EMV filter (1) according to any one of the preceding claims, wherein be additionally provided with push-pull type choke coil work For additional filter part, the push-pull type choke coil dependent on it is set be positioned in using required damping it is described Between common mode choke (10) and the X capacitor (40) and it is determined specification.

8. EMV filter (1) according to any one of the preceding claims, wherein set for wherein each filter part It is equipped with individual cooling unit.

9. EMV filter (1) according to any one of the preceding claims, wherein the EMV filter (1) is to be used for The component part of the driving inverter of automotive field.