TWI834415B - Emi filter system - Google Patents

Abstract

An EMI filter system is disclosed and comprises a circuit board and a choke. The circuit board comprises at least three capacitors. The choke is arranged on the circuit board, and includes a non-circular magnetic core and at least three winding assemblies, and the winding assemblies are wound on the non-circular magnetic core. The at least three capacitors are adjacent to the choke, and the first outlets of the winding assemblies are respectively coupled with the at least three capacitors.

Description

Electromagnetic interference filtering system

This case relates to an electromagnetic interference filtering system, specifically an electromagnetic interference filtering system suitable for three-phase systems and including a choke with a non-circular magnetic core.

With the advancement and development of science and technology, various types of electrical appliances are very common and frequently used, and the use of electrical appliances inevitably requires the use of power sources to make the appliances operate normally. However, when electrical appliances need to use AC power to operate, the current supplied by the AC power may be entrained in the current due to the power supply, the parasitic capacitance of the high-frequency transformer or other components, or the operation of stray capacitance. There is noise current, which is the phenomenon of electromagnetic interference (EMI).

Generally speaking, the noise generated by using AC power source includes differential mode noise and common mode noise, and electromagnetic interference filter can be the first line of defense for the power supply against electromagnetic radiation. The electromagnetic interference filter is mainly composed of a choke and a capacitor. The choke is an inductive component used to suppress the generation of noise, and generally consists of at least one winding, a magnetic core group and a power supply. The winding is composed of a winding frame.

Figure 1A and Figure 1B respectively show schematic diagrams of traditional electromagnetic interference chokes at different angles. As shown in FIGS. 1A and 1B , a conventional choke 1 usually includes a circular magnetic core 11 with a hollow portion and a plurality of coils 12 , and the plurality of coils 12 are wound around the hollow circular magnetic core 11 .

Generally speaking, in order to increase the inductance of the conventional choke 1, it is usually necessary to increase the number of turns of the coil 12. However, as shown in Figure 1B, the inner diameter of the circular magnetic core 11 is fixed, which means that the space in the hollow part of the circular magnetic core 11 is limited. Therefore, in this conventional technology, only 3 sets of coils can be provided. 121, 122, and 123 are arranged around it. In other words, even if you want to increase the number of coils 12 or the number of turns to increase the inductance, you will be limited by the inner diameter of the circular magnetic core 11 and it will be difficult to further increase the number of coils 12 and the number of turns.

In addition, since the center of the inner diameter of the circular magnetic core 11 is smaller (that is, the space in the hollow part of the circular magnetic core 11 is smaller), when a larger current flows through the coil 12, the choke 1 may Due to the safety distance problem between the coils 12, it is difficult to route the wiring on the circuit board 3 (as shown in Figure 1C), thereby affecting its layout. For example, as shown in Figure 1A, because the pins 121a and 122a of the coils 121 and 122 wound around the circular magnetic core 11 are too close to each other, when they are laid out in the circuit as shown in Figure 1C When it is on the board 3, the safety distance between the pins 121a and 122a will cause wiring difficulties. As can be seen from Figure 1C, since the three sets of coils 12 are arranged diagonally to each other, the outlet positions of some of the pins 121a, 122a, etc. on the circuit board 3 may be at irregular bevels ( That is, it is not a horizontal or vertical position), which will further affect the placement and quantity of other electronic components 30 or capacitors 31 on the circuit board 3, making the design of the circuit board 3 difficult.

What's more, in other conventional technologies, in order to solve the problems of inductance and safety distance of the conventional choke 1, it is necessary to use a larger size circular magnetic core 11 to increase the inductance and comply with the safety distance, so As a result, the conventional choke 1 will be larger in size, which will lead to a larger product size and the inability to miniaturize the electronic equipment.

Therefore, how to develop an electromagnetic interference filtering system that can improve the problems encountered in the above-mentioned existing technologies is actually one of the important issues.

One of the purposes of this case is to provide an electromagnetic interference filtering system, especially an electromagnetic interference filtering system suitable for three-phase systems and including a choke with a non-circular magnetic core. The inner diameter of the non-circular magnetic core is relatively small. Large, the winding position of the winding group can be separated by a certain distance, thereby solving the wiring problem of the circuit board in the conventional technology.

Another object of the present case is to provide an electromagnetic interference filtering system, which includes an electromagnetic interference filtering system with a choke having a non-circular magnetic core, through the shape of the non-circular magnetic core and at least three or more sets of windings. The winding position and series and parallel connection methods can flexibly adjust the number and position of capacitors on the circuit board, thereby effectively increasing the space utilization of the circuit board. At the same time, the overall device size can be reduced, the inductance can be increased, or the current can be shunted. , the effect of reducing losses.

According to the concept of this case, this case provides an electromagnetic interference filtering system, including a circuit board and a choke. The circuit board is equipped with at least three capacitors. The choke is installed on the circuit board and includes: a non-circular magnetic core and at least three or more sets of winding groups, which are wound on the non-circular magnetic core. Among them, at least three or more capacitors are arranged adjacent to the choke, and the first outlet terminals of the winding groups are respectively connected to at least three or more capacitors.

According to the concept of this case, the non-circular magnetic core has a hollow part. When at least three or more sets of winding groups are wound on the non-circular magnetic core, part of the winding groups pass through the hollow part of the non-circular magnetic core. department.

According to the concept of this case, the non-circular magnetic core is an elliptical annular magnetic core.

According to the concept of this case, the non-circular magnetic core includes an elliptical annular body and a U-shaped extension.

According to the concept of this case, when the choke is arranged on the circuit board, at least three or more capacitors are arranged adjacent to one side of the choke.

According to the concept of this case, when the choke is arranged on the circuit board, at least three or more capacitors are respectively arranged adjacent to two opposite sides of the choke.

According to the concept of this case, at least three or more winding groups are arranged in series, in parallel, or in series and parallel.

According to the concept of this case, the electromagnetic interference filtering system further includes an additional circuit board. The additional circuit board has at least one capacitor for corresponding connection with the second outlet terminals of at least three or more groups of windings.

According to the concept of this case, this case provides an electromagnetic interference filtering system, including: a circuit board, an additional circuit board and a choke. The circuit board is equipped with at least three capacitors. The additional circuit board is provided with at least one capacitor. The choke is sandwiched between the circuit board and the additional circuit board, and includes: a non-circular magnetic core and at least three or more sets of winding groups, which are wound on the non-circular magnetic core. Among them, at least three capacitors on the circuit board and at least one capacitor on the additional circuit board are located adjacent to the choke, and the first outlet terminals of at least three or more winding groups are correspondingly connected to at least one capacitor on the circuit board. More than three capacitors, and the second outlet terminals of at least three or more winding groups are correspondingly connected to at least one capacitor on the additional circuit board.

According to the concept of this case, the bottom side of the choke is correspondingly arranged on the circuit board, and the top side of the choke is arranged correspondingly on the additional circuit board.

1: Conventional choke

11: Round magnetic core

12, 121, 122, 123: Coil

121a, 122a: Pin

2: choke

21: Non-circular core

210: Hollow part

211:First Magnetic Department

212:Second Magnetic Department

213:The third magnetic department

214:Fourth Magnetic Department

215: Elliptical ring body

216:U-shaped extension

22: Winding group

22a: First outlet terminal

22b: The second outlet terminal

3: Circuit board

30: Electronic components

31, 61: Capacitor

31a:Y capacitor

31b:X capacitor

4, 5, 7: Electromagnetic interference filtering system

6:Additional circuit

Figure 1A and Figure 1B respectively show schematic diagrams of traditional electromagnetic interference chokes at different angles.

Figure 1C is a schematic diagram of the traditional electromagnetic interference choke shown in Figure 1A installed on a circuit board.

Figure 2 is a schematic diagram of the electromagnetic interference filtering system that is better implemented in this case.

Figure 3 is a schematic diagram of the choke shown in Figure 2.

Figure 4A is a schematic diagram of the choke coil of the second preferred implementation of the electromagnetic interference filtering system in this case.

Figure 4B is a schematic diagram of the choke coil of the electromagnetic interference filtering system of the third preferred implementation of this case.

Figure 5A is a schematic side view of the electromagnetic interference filtering system of the fourth preferred implementation of this case.

Figure 5B is a schematic top view of the structure of Figure 5A.

Figure 6 is a schematic top view of the electromagnetic interference filtering system of the fifth preferred implementation of this case.

Figure 7A is a schematic side view of the electromagnetic interference filtering system of the sixth preferred implementation of this case.

Figure 7B is a schematic top view of the structure of Figure 7A.

Figure 8 is a schematic three-dimensional structural diagram of the electromagnetic interference filtering system of the seventh preferred implementation of this case.

Some typical embodiments embodying the features and advantages of this case will be described in detail in the following description. It should be understood that this case can have various changes in different aspects without departing from the scope of this case, and the descriptions and illustrations are essentially for illustrative purposes rather than limiting this case.

Please refer to Picture 2 and Picture 3. Figure 2 is a schematic diagram of the electromagnetic interference filtering system that is better implemented in this case. Figure 3 is a schematic diagram of the choke shown in Figure 2. In this embodiment, the electromagnetic interference filtering system 4 is suitable for a three-phase system and includes a circuit board 3 and a choke 2 . The choke 2 can be but is not limited to one type of Noise filters or inductors are used in circuit board components of electronic equipment such as switching power supplies to suppress electromagnetic noise. The circuit board 3 is provided with a plurality of electronic components 30 , including at least three capacitors 31 . The choke 2 is provided on the circuit board 3 and includes a non-circular magnetic core 21 and at least three or more sets of windings 22 . The non-circular magnetic core 21 has a hollow portion 210 inside, and at least three or more sets of winding groups 22 are correspondingly wound on the non-circular magnetic core 21 . The non-circular magnetic core 21 can be in any shape other than a circle. In this embodiment, the shape of the non-circular magnetic core 21 is an elliptical annular core that is close to a square, but is not limited to this. And, when the choke 2 is disposed on the circuit board 3, at least three or more capacitors 31 are disposed adjacent to one side of the choke 2, and the first outlet terminals 22a of the at least three or more winding groups 22 are They are respectively connected to the at least three capacitors 31 .

As shown in Figure 3, in this embodiment, the non-circular magnetic core 21 of the choke 2 is in the form of an elliptical annular magnetic core and includes a first magnetic part 211, a second magnetic part 212, and a third magnetic part. 213 and the fourth magnetic part 214, in which the first magnetic part 211 and the second magnetic part 212 correspond to each other and are arranged in parallel, the third magnetic part 213 and the fourth magnetic part 214 also correspond to each other and are arranged in parallel, and the third magnetic part 213 and the fourth magnetic part 214 are respectively disposed between the first magnetic part 211 and the second magnetic part 212, and the lengths of the first magnetic part 211 and the second magnetic part 212 are longer than the third magnetic part 213 and the fourth magnetic part. 214. In this embodiment, the joints between the first magnetic part 211, the second magnetic part 212, the third magnetic part 213 and the fourth magnetic part 214 have a rounded structure, but are not limited to this. Taking this embodiment as an example, the winding groups 22 can be, but are not limited to, copper foil coils, and their number is six. However, the shape of the non-circular magnetic core 21 and the number and material of the winding groups 22 are not limited to six. This is a limitation and may be changed according to actual implementation conditions. In this embodiment, six sets of winding sets 22 are wound around the non-circular magnetic core 21 and are spaced apart from each other, and a part of each winding set 22 passes through the hollow portion 210 of the non-circular magnetic core 21 . In some embodiments, two of the six sets of windings 22 are wound on the first magnetic part 211 , three sets are wound on the second magnetic part 212 , and one set is wound on the third magnetic part 213 . The outlet positions are generally arranged in a regular manner, that is, horizontally or vertically. List. However, the winding position of the winding group 22 in this case is not limited to this, and it can be changed according to the actual implementation situation.

Please also refer to Figure 1C and Figure 2. In this embodiment, since the non-circular magnetic core 21 is an elliptical annular magnetic core, the hollow portion 210 inside the non-circular magnetic core 21 has a larger space, so that the winding distance between the winding groups 22 can be determined according to actual wiring requirements. Adjustment: Compared with the conventional technology shown in Figure 1C, the winding distance of the winding group 22 of this embodiment is larger, thereby solving the problem of difficult wiring in the conventional technology. In addition, in this embodiment, the elliptical ring-shaped magnetic core is wound with 6 sets of winding sets 22. Therefore, when the 6 sets of winding sets 22 are arranged in series, the number of turns is obviously higher than that of each in the conventional technology. The coil 12 has a large number of turns. In other words, the winding group 22 of this embodiment can increase the inductance by connecting multiple groups of windings 22 in series. In other embodiments, when the inductance is the same, if you want to disperse the current to reduce losses when the current is too large, the six groups of windings 22 can be arranged in parallel, but the current can be shunted, thereby reducing losses. Furthermore, if the electromagnetic interference filtering system 4 of this embodiment is compared with the conventional technology, it can be seen from Figure 2 that since the non-circular magnetic core 21 of this embodiment is an elliptical ring-shaped magnetic core, its six sets of windings When the group 22 is wound around an elliptical annular magnetic core, its outlet positions are generally arranged in a regular manner, that is, in a horizontal or vertical direction. Therefore, when it is installed on the circuit board 3, its outlet positions are surrounded by There is sufficient space for the installation of electronic components. Therefore, 14 electronic components can be installed on the circuit board 3 of this case, and there is little idle space on the circuit board 3. Looking back at Figure 1C, since the choke 1 in the conventional technology is a circular magnetic core 11, and its three sets of coils 12 are wound diagonally on the circular magnetic core 11, the outlet position is deviated. The bevel is an oblique method, so it is limited by the shape of the circular magnetic core 11 and its skewed outlet position. It is difficult to arrange electronic components around it. Therefore, only 11 electronic components can be placed on the circuit board 3 in the conventional technology. components, and the circuit board 3 has a lot of space that is difficult to use, so its space utilization rate is obviously poor. It can be seen that in this embodiment, an elliptical annular magnetic core is used as the non-circular magnetic core 21, and at least three or more sets of winding groups 22 are wound around the non-circular magnetic core 21 in a substantially horizontal or vertical manner. It can effectively improve the space utilization rate of the circuit board 3 and increase the number of electronic components on the circuit board 3, thereby facilitating the layout, planning and design of the circuit board 3. Of course, the number of electronic components on the circuit board 3 of this embodiment is not limited to the above number, and can be changed according to the actual implementation situation.

Please refer to Figure 4A and Figure 4B. Figure 4A is a schematic diagram of the choke coil of the second preferred implementation of the electromagnetic interference filtering system in this case. Figure 4B is a schematic diagram of the choke coil of the electromagnetic interference filtering system of the third preferred implementation of this case. As can be seen from Figures 4A and 4B, the shape of the non-circular magnetic core 21 of the choke 2 of this embodiment is not limited to an elliptical ring core, and it can also be irregular. In some embodiments, the non-circular magnetic core 21 of the choke 2 is a wavy annular core, and it also has a hollow portion inside. As shown in Figure 4A, the at least three or more groups of windings 22 are separated from each other. The windings are groundly wound on the non-circular magnetic core 21 of the wavy ring-shaped magnetic core, and a part of each winding group 22 passes through the hollow portion 210 of the non-circular magnetic core 21 . In other embodiments, the non-circular magnetic core 21 of the choke 2 is a star-shaped toroidal core as shown in Figure 4B, in which the at least three or more sets of winding groups 22 are also wound around the star-shaped toroidal core. on the non-circular magnetic core 21 and are separated from each other, and a part of each winding group 22 passes through the hollow portion 210 of the non-circular magnetic core 21 . It can be seen from this that the non-circular magnetic core 21 of the choke 2 in this case can be in any shape other than circular. It can have various shapes and can be changed according to the actual implementation situation. The aforementioned forms are limited.

Please refer to Figure 5A and Figure 5B. Figure 5A is a schematic side view of the electromagnetic interference filtering system of the fourth preferred implementation of this case. Figure 5B is a schematic top view of the structure of Figure 5A. In this embodiment, the electromagnetic interference filtering system 4 also includes a circuit board 3 and a choke 2 . The choke 2 is arranged on the circuit board 3 and includes a non-circular magnetic core 21 and at least three or more sets of winding groups 22. At least three or more groups of winding groups 22 are wound on the non-circular magnetic core 21 and are connected to each other. Separatedly arranged, a portion of each winding group 22 passes through the hollow portion 210 of the non-circular magnetic core 21 . In this embodiment, the number of turns of any two sets of windings 22 is the same, so they can be connected in series or in parallel according to different situations to increase the inductance or shunt the current as in the previous embodiment. Of course, In other embodiments, a series-parallel arrangement may also be adopted, and the arrangement may be changed according to actual implementation conditions, but is not limited thereto. And, the circuit board 3 has at least three or more capacitors 31. Taking this embodiment as an example, the number of the at least three or more capacitors 31 is 3. These three capacitors 31 are adjacent to one side of the choke 2. And the first outlet terminals 22a of the at least three or more groups of windings 22 are respectively connected to the three capacitors 31. As for the second outlet terminals 22b of the at least three or more groups of windings 22, they may be connected to the three capacitors 31 through wiring. Another remote circuit board (not shown) is connected correspondingly to the capacitor (not shown) on the remote circuit board. In other words, taking this embodiment as an example, it mainly shows that one side of the choke 2 can be directly electrically connected to at least three capacitors 31 on the circuit board 3, and the other side can be connected to a remote circuit board (not shown in the figure) through wiring. ) electrical connection. However, in other embodiments, the circuit board 3 may also have 4, 5 or 6 capacitors 31 , and they may be correspondingly disposed on two opposite sides of the winding group 2 , or on any two sides. The number and location of the capacitors 31 are mainly controlled based on the shape of the non-circular magnetic core 21 of the choke 2 and the outlet position of the winding group 2, but are not limited thereto. Furthermore, in some embodiments, the capacitor 31 may include a Y capacitor 31a and an X capacitor 31b. In this case, the first outlet terminals 22a of the at least three or more groups of windings 22 are correspondingly connected to the Y capacitor 31a and the X capacitor at the same time. 31b, but not limited thereto. In other embodiments, the choke 2 can be a differential mode inductor or a common mode inductor, and it can be arbitrarily matched with the required Y capacitor 31a and X capacitor 31b, and its number and arrangement are not limited thereto.

See Figure 6. Figure 6 is a schematic top view of the electromagnetic interference filtering system of the fifth preferred implementation of this case. In this embodiment, the structure and arrangement of the circuit board 3 and the choke 2 of the electromagnetic interference filtering system 4 are substantially the same as those in the previous embodiment. However, in this embodiment, the shape of the non-circular magnetic core 21 of the choke 2 is a combination of an elliptical ring-shaped magnetic core and a U-shaped magnetic core. In other words, the non-circular magnetic core 21 has an elliptical annular body 215, and a part of the elliptical annular body 215 protrudes outward to form a U-shaped extension 216, that is, both ends of the elliptical annular body 215 and both ends of the U-shaped extension 216 Corresponding connection. In this embodiment, at least three or more winding groups 22 are wound on the elliptical annular body 215 separately from each other, and are not wound on the U-shaped extension. On the extension part 216. However, in other embodiments, the winding set 22 can also be wound on the U-shaped extension 216 to match the wiring configuration of the circuit board 3 and the position of the capacitor 31 on the circuit board 3 . Therefore, the shape of the non-circular magnetic core 21 and the winding positions of at least three or more winding groups 22 can be changed in accordance with the configuration of the circuit board 3 .

Please refer to Figure 7A and Figure 7B. Figure 7A is a schematic side view of the electromagnetic interference filtering system of the sixth preferred implementation of this case. Figure 7B is a schematic top view of the structure of Figure 7A. As shown in Figures 7A and 7B, the electromagnetic interference filtering system 5 of this embodiment not only includes the circuit board 3 and the choke 2, but also includes another additional circuit board 6. It can be seen from Figure 7A that the choke 2 of this embodiment is sandwiched between the circuit board 3 and the additional circuit board 6 to form a sandwich type electromagnetic interference filtering system 5. In this embodiment, the top side of the choke 2 is connected to the additional circuit board 6, and the bottom side is connected to the circuit board 3, so that the choke 2 is sandwiched between the circuit board 3 and the additional circuit board 3. between circuit boards 6. As shown in Figure 7B, the choke 2 also includes a non-circular magnetic core 21 and at least three or more sets of winding sets 22. In this embodiment, the number of the at least three or more sets of winding sets 22 is 6, that is, in this embodiment The six sets of winding sets 22 in the embodiment are wound on the non-circular magnetic core 21 and are spaced apart from each other. A part of each winding set 22 passes through the hollow portion 210 of the non-circular magnetic core 21 . Similar to the previous embodiment, the circuit board 3 has at least three capacitors 31. Taking this embodiment as an example, the circuit board 3 has three capacitors, and these three capacitors 31 are adjacent to one side of the choke 2. And correspondingly connected to the first outlet terminals 22a of the six groups of winding groups 22. Similarly, the additional circuit board 6 is also provided with at least three or more capacitors 61, and in this embodiment, the number of the at least three or more capacitors 61 is 3, and as shown in Figure 7A, these three capacitors 61 are correspondingly arranged on the two opposite sides of the choke 2, that is, two capacitors 61 are arranged on one side of the choke 2, and the other capacitor 61 is arranged on the other side of the choke 2, so as to separate the choke. The current converter 2 is sandwiched between the three capacitors 61. And, these three capacitors 61 are connected correspondingly to the second outlet terminals 22b of the six sets of winding groups 22. In this embodiment, since the capacitor 31 on the circuit board 3 and the capacitor 61 on the additional circuit board 6 are both located adjacent to the choke 2, they can effectively suppress electromagnetic interference. In some embodiments, the capacitor 31 and the capacitor 61 can be locked to correspond to adjacent Set in choke 2, but not limited to this. In addition, through the sandwich arrangement of this embodiment, the position and quantity of components on the circuit board 3 and the additional circuit board 6 can be more flexibly adjusted. For example, when the space of the circuit board 3 is not enough to arrange 6 capacitors 31, for example, only 3 capacitors or 4 capacitors can be arranged, through the arrangement of the additional circuit board 6, it can help to arrange the 3 capacitors or 4 capacitors that cannot be arranged. Two capacitors are installed on the additional circuit board 6 to regulate or increase the capacitance 61 on the branch circuit. In this way, through the arrangement of the three-dimensional interlayer, the horizontal outlet direction of the winding group 22 can be changed to the vertical up and down outlet direction, thereby reducing the overall volume of the electromagnetic interference filtering system 5 and improving the circuit efficiency. Space utilization of board 3 and additional circuit board 6.

See Figure 8. Figure 8 is a schematic three-dimensional structural diagram of the electromagnetic interference filtering system of the seventh preferred implementation of this case. In this embodiment, the structures of the circuit board 3 and the choke 2 of the electromagnetic interference filtering system 7 are substantially the same as those in the previous embodiment, that is, the circuit board 3 includes at least three capacitors 31 , and the choke 2 is disposed on the circuit board 3 on the non-circular magnetic core 21, and includes a non-circular magnetic core 21 and at least three or more sets of winding groups 22. At least three or more groups of winding groups 22 are wound on the non-circular magnetic core 21 and are spaced apart from each other. Each winding group 22 A part passes through the hollow portion 210 of the non-circular magnetic core 21 . However, in this embodiment, the number of at least three capacitors 31 on the circuit board 3 is 3, and one of them is disposed on one side of the choke 2, and the other two capacitors 31 are disposed on one side of the choke 2 correspondingly. other side. In other words, the three capacitors 31 are respectively located adjacent to two opposite sides of the choke 2, and the at least three or more sets of winding sets 22 are sandwiched therebetween, and are connected with the at least three or more sets of winding sets 22. The first outlet terminal 22a (not shown) is connected correspondingly. It can be seen that the number and location of the capacitors 31 on the circuit board 3 can be changed according to the size and actual situation of the circuit board 3, and is not limited thereto. However, these changes require at least three capacitors. 31 is arranged adjacent to the choke 2 to achieve the effect of suppressing electromagnetic interference.

To sum up, this case provides an electromagnetic interference filtering system, including a circuit board and a choke, and the choke includes a non-circular magnetic core and at least three or more sets of windings, wherein the at least three or more sets of windings The capacitor is wound around the non-circular magnetic core and connected to and adjacent to the capacitor on the circuit board. Because of this non-circular The inner diameter of the magnetic core is relatively large, so the winding positions of at least three or more sets of windings can be spaced apart to a certain distance, thereby solving the wiring problem of the circuit board in the conventional technology. Furthermore, by arranging at least three or more winding groups in series, the inductance can be greatly increased, or by arranging at least three or more winding groups in parallel, the current can be shunted and the loss can be reduced. It can be seen that through the non-circular magnetic core type of the choke in this case and the winding position of at least three or more winding groups and the series and parallel connection methods, the number and position of the capacitors on the circuit board can be flexibly adjusted. This effectively increases the space utilization of the circuit board, and at the same time achieves the effects of suppressing electromagnetic interference, reducing the size of the overall device, increasing the inductance, or shunting current to reduce losses.

This case may be modified in various ways by those who are familiar with this technology, but none of them will deviate from the intended protection within the scope of the patent application.

2: choke

21: Non-circular core

22: Winding group

22a: First outlet terminal

3: Circuit board

30: Electronic components

31: Capacitor

4:Electromagnetic interference filtering system

Claims (10)

An electromagnetic interference filtering system, suitable for a three-phase system, includes: a circuit board equipped with at least three capacitors; and a choke, installed on the circuit board, and includes: a non-circular magnetic core, It is an integrally formed structure; and at least three or more sets of winding groups are wound on the non-circular magnetic core, and their number is a multiple of three; among which, the at least three or more capacitors are located adjacent to the In the choke, the number of the at least three or more capacitors corresponds to the at least three or more winding groups, and the first outlet end of one of the at least three or more winding groups is respectively connected to the at least three or more capacitors. The electromagnetic interference filtering system of claim 1, wherein the non-circular magnetic core has a hollow portion. When the at least three or more winding groups are wound on the non-circular magnetic core, a part of the winding groups Passing through the hollow portion of the non-circular magnetic core. The electromagnetic interference filtering system of claim 1, wherein the non-circular magnetic core is an elliptical ring-shaped magnetic core. The electromagnetic interference filtering system of claim 1, wherein the non-circular magnetic core includes an elliptical annular body and a U-shaped extension. The electromagnetic interference filtering system of claim 1, wherein when the choke is disposed on the circuit board, the at least three capacitors are disposed adjacent to one side of the choke. The electromagnetic interference filtering system of claim 1, wherein when the choke is installed on the circuit board, the at least three capacitors are respectively located adjacent to two opposite sides of the choke. The electromagnetic interference filtering system of claim 1, wherein the at least three or more groups of winding groups are arranged in series, in parallel, or in series and parallel. The electromagnetic interference filtering system of claim 1, wherein the electromagnetic interference filtering system further includes an additional circuit board, the additional circuit board has at least one capacitor for connecting with the second second of one of the at least three or more winding groups. The outlet terminals are connected accordingly. An electromagnetic interference filtering system, suitable for a three-phase system, including: a circuit board provided with at least three capacitors; an additional circuit board provided with at least one capacitor; and a choke installed on the circuit board and the additional circuit board, and includes: a non-circular magnetic core, which is an integrally formed structure; and at least three or more sets of winding groups, which are wound on the non-circular magnetic core, and their The number is a multiple of three; wherein, the at least three capacitors on the circuit board and the at least one capacitor on the additional circuit board are adjacent to the choke, and the at least three capacitors on the circuit board The number corresponds to the at least three or more winding groups, and one of the first outlet terminals of the at least three or more winding groups corresponds to the at least three or more capacitors on the circuit board. The at least three or more winding groups One of the second outlet terminals of the wire group is correspondingly connected to the at least one capacitor on the additional circuit board. The electromagnetic interference filtering system of claim 9, wherein a bottom side of the choke is disposed on the circuit board, and a top side of the choke is disposed on the additional circuit board.

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