CN114190041B

CN114190041B - Electromagnetic interference filtering structure of power supply module

Info

Publication number: CN114190041B
Application number: CN202111316306.4A
Authority: CN
Inventors: 赵键; 段中焕; 栾璟明; 江洋
Original assignee: Shaanxi Qianshan Avionics Co Ltd
Current assignee: Shaanxi Qianshan Avionics Co Ltd
Priority date: 2021-11-08
Filing date: 2021-11-08
Publication date: 2023-10-20
Anticipated expiration: 2041-11-08
Also published as: CN114190041A

Abstract

The application provides an electromagnetic interference filtering structure of a power supply module, which belongs to the technical field of avionics and particularly comprises a printed board and a cold board, wherein a transducer is arranged on the printed board, a filter is coupled and connected between the transducer and the printed board, and the printed board is electrically connected with the cold board so that the filter is coupled into the cold board. By the processing scheme, the actual filtering effect of common-mode interference is improved.

Description

Electromagnetic interference filtering structure of power supply module

Technical Field

The application relates to the field of avionics technology, in particular to an electromagnetic interference filtering structure of a power supply module.

Background

A certain type of flight parameter collector belongs to a certain type of aircraft onboard matching product, and is used for collecting sensor data, bus data, audio data and video data on an aircraft in real time and sending the collected data to a fixed storage device. The power module electromagnetic interference filtering structure is arranged in the flight parameter collector, receives a 28V direct current power supply input by an airplane, converts the input 28V direct current power supply into low-voltage power supplies of +12V, +15V, -15V, +5V, +3.3V and the like through a plurality of DC/DC converters in the power module electromagnetic interference filtering structure, and provides power supply for other functional board cards in the flight parameter collector. The DC/DC converter used in the electromagnetic interference filtering structure of the power supply module belongs to a switching power supply converter, and in the working process, MOSFETs which play a role in switching and rectification in the DC/DC converter are in a switching state at a working frequency of hundreds of KHz, and the differential mode interference and the common mode interference are inevitably generated on power supply loops of 28V, +12V, +15V, +5V and the like. Under the action of frequency doubling, in the frequency range of hundreds KHz-hundreds MHz, the electromagnetic environment of a power supply loop is seriously polluted, and the normal operation of other functional boards inside the flight parameter collector or other airborne equipment crosslinked with the flight parameter collector is possibly influenced.

For electromagnetic interference generated by the DC/DC converter, a power supply filter is arranged on an electromagnetic interference filtering structure of a power supply module in a conventional processing mode, and differential mode interference and common mode interference are filtered.

For the differential mode interference, the differential mode interference can be effectively filtered through an X capacitor, a differential mode choke coil and the like in the power filter.

For common mode interference, the DC/DC converter is required to be in large-area effective contact with the filter shell, otherwise, the filtering effect of the Y capacitor and the common mode choke coil in the power filter on the common mode interference is greatly reduced, and even the power filter is disabled.

In the actual operation process, although the power filter and the DC/DC converter are positioned on the electromagnetic interference filtering structure of the power module, the power filter and the DC/DC converter are far away from each other, and can only be connected through the printed wiring on the circuit board for shell connection, and cannot be effectively contacted in a large area, so that the actual filtering effect of common-mode interference is not ideal.

Disclosure of Invention

In view of the above, the present application provides an electromagnetic interference filtering structure of a power module, which solves the problem of poor actual filtering effect of common-mode interference of a DC/DC converter in the prior art, and improves the actual filtering effect of common-mode interference

The electromagnetic interference filtering structure of the power supply module provided by the application adopts the following technical scheme:

the utility model provides a power module electromagnetic interference filtering structure, includes printed board and cold plate, install the converter on the printed board, the converter with coupling connection wave filter between the printed board, the printed board is connected with the cold plate electricity, makes the wave filter couple in the cold plate.

Optionally, be equipped with the breach on the side of printed board, cover first conducting layer on the inner wall of breach, the conducting layer passes through printed board and is connected with the converter electricity, the depressed part has been seted up on the cold plate, cover the second conducting layer on the depressed part inner wall, first conducting layer and second conducting layer electricity are connected.

Optionally, the recess is filled with solder, and the first conductive layer is electrically connected with the second conductive layer through the solder.

Optionally, the depth of the concave part ranges from 0.5 mm to 1mm.

Optionally, the filter is a ceramic filter capacitor.

Optionally, filters are connected between the input positive, the input ground, the output positive and the output ground of the converter and the printed board.

Optionally, the electromagnetic interference filtering structure of the power supply module is used for being installed in the flight parameter collector, an installation groove is formed in the inner wall of the chassis of the flight parameter collector, the edge of the cold plate is inserted into the installation groove, a locking device is fixed on the cold plate, and the locking device tightly sticks the cold plate to the inner wall of one side of the installation groove.

Optionally, the locking device is a wedge locking mechanism.

In summary, the application has the following beneficial technical effects:

by coupling the filter into the cold plate, a filtered path is effectively constructed for common mode interference generated by the DC/DC converter. The electromagnetic interference filtering structure of the power supply module is arranged on the internal slot position of the flight parameter collector, and after the locking device locks, the cold plate is tightly contacted with the metal case, and common mode interference is coupled to the metal case. The metal chassis is arranged on the aircraft through the metal mounting frame, common-mode interference can be coupled into the aircraft reference ground, and the actual filtering effect of the common-mode interference is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of an electromagnetic interference filtering structure of a power module according to the present application;

FIG. 2 is a schematic diagram of an electromagnetic interference filter structure of a power module according to another embodiment of the present application;

FIG. 3 is a schematic diagram of the connection structure of the transducer and the printed board of the present application;

FIG. 4 is a schematic diagram of the electrical connection between a cold plate and a printed board according to the present application;

fig. 5 is a schematic structural diagram of the electromagnetic interference filtering structure of the power module mounted on the chassis.

Reference numerals illustrate: 1. a printed board; 2. a cold plate; 3. a transducer; 4. a copper-clad layer; 5. a filter; 6. a notch; 61. a first conductive layer; 7. a recessed portion; 71. a second conductive layer; 8. a locking device; 9. a mounting groove; 10. and a case.

Detailed Description

Embodiments of the present application will be described in detail below with reference to the accompanying drawings.

Other advantages and effects of the present application will become apparent to those skilled in the art from the following disclosure, which describes the embodiments of the present application with reference to specific examples. It will be apparent that the described embodiments are only some, but not all, embodiments of the application. The application may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present application. It should be noted that the following embodiments and features in the embodiments may be combined with each other without conflict. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

It is noted that various aspects of the embodiments are described below within the scope of the following claims. It should be apparent that the aspects described herein may be embodied in a wide variety of forms and that any specific structure and/or function described herein is merely illustrative. Based on the present disclosure, one skilled in the art will appreciate that one aspect described herein may be implemented independently of any other aspect, and that two or more of these aspects may be combined in various ways. For example, an apparatus may be implemented and/or a method practiced using any number of the aspects set forth herein. In addition, such apparatus may be implemented and/or such methods practiced using other structure and/or functionality in addition to one or more of the aspects set forth herein.

It should also be noted that the illustrations provided in the following embodiments merely illustrate the basic concept of the present application by way of illustration, and only the components related to the present application are shown in the drawings and are not drawn according to the number, shape and size of the components in actual implementation, and the form, number and proportion of the components in actual implementation may be arbitrarily changed, and the layout of the components may be more complicated.

In addition, in the following description, specific details are provided in order to provide a thorough understanding of the examples. However, it will be understood by those skilled in the art that the aspects may be practiced without these specific details.

The embodiment of the application provides an electromagnetic interference filtering structure of a power supply module.

As shown in fig. 1, 2 and 3, an electromagnetic interference filtering structure of a power module comprises a printed board 1 and a cold board 2, wherein the printed board 1 and the cold board 2 are bonded under a high temperature condition through insulating glue. The converter 3 is arranged on the printed board 1, the converter 3 is a DC/DC converter 3, the converter 3 is arranged on the printed board 1 closely to the cold board 2, the filter 5 is coupled between the converter 3 and the printed board 1, the filter 5 is coupled into the copper-clad layer 4 of the printed board 1, the printed board 1 is electrically connected with the cold board 2, and the filter 5 is coupled into the cold board 2.

By coupling the filter 5 into the cold plate 2, a filtered path is effectively constructed for the common-mode interference generated by the DC/DC converter 3. The electromagnetic interference filtering structure of the power supply module is arranged in an inner installation groove 9 of the flight parameter collector, and after the locking device 8 is used for locking, the cold plate 2 is tightly contacted with the metal case 10, and common mode interference is coupled to the metal case 10. The metal chassis 10 is installed on the aircraft through a metal installation frame, so that common mode interference can be coupled into the aircraft reference ground, and the actual filtering effect of the common mode interference is improved.

As shown in fig. 4, in order to realize the electrical connection between the printed board 1 and the cold board 2, a notch 6 is provided on the side edge of the printed board 1, a first conductive layer 61 is covered on the inner wall of the notch 6, the first conductive layer 61 on the notch 6 is electrically connected with the copper-clad layer 4 in the printed board 1, the conductive layer is electrically connected with the transducer 3 through the printed board 1, a concave portion 7 is provided on the cold board 2, the size of the concave portion 7 is the same as the size of the notch 6, and the concave portion 7 overlaps with the notch 6. The inner wall of the concave part 7 is covered with a second conductive layer 71, and the first conductive layer 61 and the second conductive layer 71 are electrically connected, so that the copper-clad layer 4 in the printed board 1 is electrically connected with the cold board 2.

The recess 7 is filled with solder (not shown), the first conductive layer 61 is electrically connected to the second conductive layer 71 by solder, and the solder fills the recess 7 and is soldered to the first conductive layer 61 of the notch 6.

The depth of the recess 7 is in the range of 0.5-1mm.

The filter 5 is a ceramic filter capacitor.

The filter 5 is connected between the input positive, input ground, output positive and output ground of the inverter 3 and the printed board 1.

As shown in fig. 1 and 5, the electromagnetic interference filtering structure of the power module is used for being installed in the flight parameter collector, an installation groove 9 is formed in the inner wall of a chassis 10 of the flight parameter collector, the edge of the cold plate 2 is inserted into the installation groove 9, a locking device 8 is fixed on the cold plate 2, the locking device 8 and the cold plate 2 are fixedly connected through rivets, and the locking device 8 clings the cold plate 2 to the inner wall of one side of the installation groove 9.

As shown in fig. 1, the locking device 8 is a wedge-shaped locking mechanism.

The foregoing is merely illustrative of the present application, and the present application is not limited thereto, and any changes or substitutions easily contemplated by those skilled in the art within the scope of the present application should be included in the present application. Therefore, the protection scope of the application is subject to the protection scope of the claims.

Claims

1. The power module electromagnetic interference filtering structure comprises a printed board and a cold board, wherein a converter is arranged on the printed board and is a DC/DC converter, and a filter is coupled between the converter and the printed board;

the electromagnetic interference filtering structure of the power module is used for being installed in the flight parameter collector, an installation groove is formed in the inner wall of a case of the flight parameter collector, the case is made of metal, the edge of the cold plate is inserted into the installation groove, a locking device is fixed on the cold plate, the locking device tightly clings to the inner wall of one side of the installation groove, the cold plate is tightly contacted with the metal case, common mode interference is coupled to the metal case, the case is installed on an airplane through a metal installation frame, and the common mode interference is coupled to the reference ground of the airplane.

2. The electromagnetic interference filtering structure of the power supply module according to claim 1, wherein a notch is formed on a side edge of the printed board, a first conductive layer is covered on an inner wall of the notch, the conductive layer is electrically connected with the transformer through the printed board, a concave portion is formed on the cold board, a second conductive layer is covered on an inner wall of the concave portion, and the first conductive layer and the second conductive layer are electrically connected.

3. The electromagnetic interference filtering structure of claim 2, wherein the recess is filled with solder, and the first conductive layer is electrically connected to the second conductive layer through the solder.

4. The electromagnetic interference filtering structure of claim 2, wherein the depth of the recess is in the range of 0.5-1mm.

5. The electromagnetic interference filtering structure of claim 1, wherein the filter is a ceramic filter capacitor.

6. The electromagnetic interference filtering structure of the power supply module according to claim 1, wherein filters are connected between the input positive, the input ground, the output positive and the output ground of the converter and the printed board.

7. The electromagnetic interference filtering structure of claim 1, wherein the locking device is a wedge-shaped locking mechanism.