Hybrid noise filter

Abstract

hybrid noise filter is coupled between an input power source and a power converter. The hybrid noise filter includes a differential-mode filter unit and a common-mode filter unit. The differential-mode filter unit includes a differential-mode input side and a differential-mode output side, and the differential-mode input side is connected to the input power source. The differential-mode filter unit includes a differential-mode inductor and a differential-mode capacitor. The differential-mode capacitor is connected to a second winding of the differential-mode inductor in series. The common-mode filter unit includes a common-mode input side and a common-mode output side, and the common-mode input side is connected to the differential-mode output side and the common-mode output side is connected to the power converter. The common-mode filter unit includes a common-mode inductor and a first common-mode capacitor. The first common-mode capacitor is connected to a third winding of the common-mode inductor in series and to a ground terminal.

Description

[Technical Field]

[0001] This invention relates to a noise filter, and more particularly to a hybrid noise filter. [Previous Technology]

[0002] In conventional switching power converter structures, a common-mode noise filter (including capacitors C1 and C2) is typically present at its input terminal, consisting of a common-mode inductor and a Y-capacitor. This common-mode noise filter usually has one to three sets. Multiple sets of filters are needed because the bandwidth of conducted electromagnetic interference ranges from 150kHz to 30MHz, and filters typically have a limited response bandwidth.

[0003] The performance of a filter is directly related to its attenuation performance within the bandwidth. To achieve better noise attenuation, traditional common-mode inductors have two windings, N1 and N2, and require a higher inductance, resulting in higher size and cost. Furthermore, high-inductance inductors typically require more windings, leading to greater efficiency loss and heat generation. Figure 1 shows a circuit diagram of a conventional switching power converter. As can be clearly seen from Figure 1, the common-mode current (icm) is typically transmitted to ground (FG) via the secondary side, then returns to the ground terminal of the line impedance stabilization network (LISN), and is finally detected by the EMI receiver.

[0004] Therefore, how to design a noise filter, especially a hybrid noise filter, to solve the problems and technical bottlenecks of the existing technology is an important research topic for the inventors of this case. [Summary of the Invention]

[0005] One object of the present invention is to provide a hybrid noise filter. The hybrid noise filter is coupled between an input power supply and a power converter. The hybrid noise filter includes a differential-mode filter unit and a common-mode filter unit. The differential-mode filter unit has a differential-mode input side and a differential-mode output side, and the differential-mode input side is connected to the input power supply. The differential-mode filter unit includes a differential-mode inductor and a differential-mode capacitor. The differential-mode inductor includes a first winding and a second winding. The differential-mode capacitor is connected in series with the second winding of the differential-mode inductor. The common-mode filter unit has a common-mode input side and a common-mode output side. The common-mode input side is connected to the differential-mode output side, and the common-mode output side is connected to the power converter. The common-mode filter unit includes a common-mode inductor and a first common-mode capacitor. The common-mode inductor includes a first winding, a second winding, and a third winding. The first common-mode capacitor is connected in series with the third winding of the common-mode inductor and is connected to a ground terminal.

[0006] In one embodiment, the first winding of the differential-mode inductor has a first terminal and a second terminal, the second winding of the differential-mode inductor has a first terminal and a second terminal, and the differential-mode capacitor has a first terminal and a second terminal. The first terminal of the first winding is connected to the first terminal of the second winding, and the second terminal of the second winding is connected to the first terminal of the differential-mode capacitor. The first terminal of the first winding and the second terminal of the differential-mode capacitor form the differential-mode input side. The second terminal of the first winding and the second terminal of the differential-mode capacitor form the differential-mode output side.

[0007] In one embodiment, the polarity of the second end of the first winding of the differential mode inductor is the same as the polarity of the second end of the second winding of the differential mode inductor.

[0008] In one embodiment, the first winding of the common-mode inductor has a first terminal and a second terminal, the second winding of the common-mode inductor has a first terminal and a second terminal, the third winding of the common-mode inductor has a first terminal and a second terminal, and the first common-mode capacitor has a first terminal and a second terminal. The first terminal of the first winding is connected to the first terminal of the third winding, and the second terminal of the third winding is connected to the first terminal of the first common-mode capacitor. The first terminal of the first winding and the first terminal of the second winding form the common-mode input side. The second terminal of the first winding and the second terminal of the second winding form the common-mode output side.

[0009] In one embodiment, the polarity of the second end of the first winding of the common mode inductor is the same as the polarity of the second end of the second winding of the common mode inductor, and the polarity of the second end of the second winding of the common mode inductor is the same as the polarity of the second end of the third winding of the common mode inductor.

[0010] In one embodiment, the common-mode filter unit further includes a second common-mode capacitor. The second common-mode capacitor is connected between the common-mode input sides.

[0011] In one embodiment, the common-mode filter unit further includes a second common-mode capacitor. The second common-mode capacitor has a first terminal and a second terminal. The first terminal of the second common-mode capacitor is connected to the first terminal of the third winding, and the second terminal of the second common-mode capacitor is connected to the first terminal of the second winding.

[0012] Another object of the present invention is to provide a hybrid noise filter. The hybrid noise filter is coupled between an input power supply and a power converter. The hybrid noise filter includes a common-mode filter unit and a differential-mode filter unit. The common-mode filter unit has a common-mode input side and a common-mode output side, and the common-mode input side is connected to the input power supply. The common-mode filter unit includes a common-mode inductor and a first common-mode capacitor. The common-mode inductor includes a first winding, a second winding, and a third winding. The first common-mode capacitor is connected in series with the third winding of the common-mode inductor and is connected to a ground terminal. The differential-mode filter unit has a differential-mode input side and a differential-mode output side. The differential-mode input side is connected to the common-mode output side, and the differential-mode output side is connected to the power converter. The differential-mode filter unit includes a differential-mode inductor and a differential-mode capacitor. The differential-mode inductor includes a first winding and a second winding. The differential-mode capacitor is connected in series with the second winding of the differential-mode inductor.

[0013] In one embodiment, the first winding of the common-mode inductor has a first terminal and a second terminal, the second winding of the common-mode inductor has a first terminal and a second terminal, the third winding of the common-mode inductor has a first terminal and a second terminal, and the first common-mode capacitor has a first terminal and a second terminal. The first terminal of the first winding is connected to the first terminal of the third winding, and the second terminal of the third winding is connected to the first terminal of the first common-mode capacitor. The first terminal of the first winding and the first terminal of the second winding form the common-mode input side. The second terminal of the first winding and the second terminal of the second winding form the common-mode output side.

[0014] In one embodiment, the polarity of the second end of the first winding of the common mode inductor is the same as the polarity of the second end of the second winding of the common mode inductor, and the polarity of the second end of the second winding of the common mode inductor is the same as the polarity of the second end of the third winding of the common mode inductor.

[0015] In one embodiment, the first winding of the differential-mode inductor has a first terminal and a second terminal, the second winding of the differential-mode inductor has a first terminal and a second terminal, and the differential-mode capacitor has a first terminal and a second terminal. The first terminal of the first winding is connected to the first terminal of the second winding, and the second terminal of the second winding is connected to the first terminal of the differential-mode capacitor. The first terminal of the first winding and the second terminal of the differential-mode capacitor form the differential-mode input side. The second terminal of the first winding and the second terminal of the differential-mode capacitor form the differential-mode output side.

[0016] In one embodiment, the polarity of the second end of the first winding of the differential mode inductor is the same as the polarity of the second end of the second winding of the differential mode inductor.

[0017] In one embodiment, the common-mode filter unit further includes a second common-mode capacitor. The second common-mode capacitor is connected between the common-mode input sides.

[0018] In one embodiment, the common-mode filter unit further includes a second differential-mode capacitor. The second common-mode capacitor has a first terminal and a second terminal. The first terminal of the second common-mode capacitor is connected to the first terminal of the third winding, and the second terminal of the second common-mode capacitor is connected to the first terminal of the second winding.

[0019] Accordingly, the hybrid noise filter proposed in this invention can achieve the advantage of eliminating differential-mode noise current and common-mode noise current.

[0020] In order to further understand the technology, means and effects adopted by the present invention to achieve the intended purpose, please refer to the following detailed description and drawings of the present invention. It is believed that the purpose, features and characteristics of the present invention can be understood in depth and in detail from these drawings. However, the accompanying drawings are provided for reference and illustration only and are not intended to limit the present invention.

Implementation Method

[0021] The technical content and detailed description of the present invention are described below with reference to the accompanying drawings.

[0022] The following describes the implementation of this invention through specific embodiments. Those skilled in the art can easily understand other advantages and effects of this invention from the content disclosed in this specification. This invention can also be implemented or applied through other different specific examples, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the spirit of this invention.

[0023] It should be noted that the structures, proportions, sizes, number of components, etc., shown in the accompanying drawings in this specification are only used to complement the content disclosed in the specification for those familiar with the technology to understand and read, and are not intended to limit the conditions under which this creation can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportional relationships, or adjustments to the size, without affecting the effects and purposes that this creation can produce, should fall within the scope of the technical content disclosed in this creation.

[0024] Please refer to Figure 2, which is a circuit diagram of a first embodiment of the hybrid noise filter of the present invention. The hybrid noise filter is coupled between the input power supply Vac and the power converter. Incidentally, the power converter is composed of all or part of a bridge rectifier 94, a voltage conversion circuit 95, a transformer 96, a protection circuit 97, and an output rectifier 98, but this is not intended to limit the present invention.

[0025] As shown in Figure 2, the hybrid noise filter includes a differential-mode filter unit 11 and a common-mode filter unit 21. The differential-mode filter unit 11 has a differential-mode input side (i.e., the input side of the differential-mode filter unit 11) and a differential-mode output side (i.e., the output side of the differential-mode filter unit 11), wherein the differential-mode input side is connected to the input power supply Vac, more specifically, it is connected to the input power supply Vac through the power supply impedance stabilization network 91. The differential-mode filter unit 11 includes a differential-mode inductor LF2 and a differential-mode capacitor CX1. The differential-mode inductor LF2 includes a first winding N21 and a second winding N22. The differential-mode capacitor CX1 is connected in series with the second winding N22.

[0026] The common-mode filter unit 21 has a common-mode input side (i.e., the input side of the common-mode filter unit 21) and a common-mode output side (i.e., the output side of the common-mode filter unit 21), and the common-mode input side is connected to the differential-mode output side, while the common-mode output side is connected to the power converter. The common-mode filter unit 21 includes a common-mode inductor LF1 and a first common-mode capacitor CY1. The common-mode inductor LF1 includes a first winding N11, a second winding N12, and a third winding N13. The first common-mode capacitor CY1 is connected in series with the third winding N13 and is connected to the ground terminal.

[0027] Please refer to Figure 2. More specifically, the first winding N21 of the differential-mode inductor LF2 has a first terminal and a second terminal, the second winding N22 of the differential-mode inductor LF2 has a first terminal and a second terminal, and the differential-mode capacitor CX1 has a first terminal and a second terminal. The first terminal of the first winding N21 is connected to the first terminal of the second winding N22, and the second terminal of the second winding N22 is connected to the first terminal of the differential-mode capacitor CX1. The first terminal of the first winding N21 and the second terminal of the differential-mode capacitor CX1 form the differential-mode input side. The second terminal of the first winding N21 and the second terminal of the differential-mode capacitor CX1 form the differential-mode output side.

[0028] Furthermore, the polarity of the second terminal of the first winding N21 of the differential mode inductor LF2 is the same as the polarity of the second terminal of the second winding N22 of the differential mode inductor LF2. For example, in this embodiment, the second terminals of the first winding N21 and the second terminals of the second winding N22 are both dotted polarities; conversely, the first terminals of the first winding N21 and the first terminals of the second winding N22 are both undotted polarities.

[0029] Please refer to Figure 2. More specifically, the first winding N11 of the common-mode inductor LF1 has a first terminal and a second terminal, the second winding N12 of the common-mode inductor LF1 has a first terminal and a second terminal, the third winding N13 of the common-mode inductor LF1 has a first terminal and a second terminal, and the first common-mode capacitor CY1 has a first terminal and a second terminal. The first terminal of the first winding N11 is connected to the first terminal of the third winding N13, and the second terminal of the third winding N13 is connected to the first terminal of the first common-mode capacitor CY1. The first terminal of the first winding N11 and the first terminal of the second winding N12 form the common-mode input side. The second terminal of the first winding N11 and the second terminal of the second winding N12 form the common-mode output side.

[0030] Furthermore, the polarity of the second terminal of the first winding N11 of the common-mode inductor LF1 is the same as the polarity of the second terminal of the second winding N12 of the common-mode inductor LF1, and the polarity of the second terminal of the second winding N12 of the common-mode inductor LF1 is the same as the polarity of the second terminal of the third winding N13 of the common-mode inductor LF1. For example, in this embodiment, the second terminals of the first winding N11, the second winding N12, and the third winding N13 are all dotted polarities; conversely, the first terminals of the first winding N11, the second winding N12, and the third winding N13 are all undotted polarities.

[0031] In the circuit of the first embodiment shown in Figure 2, compared with the conventional circuit of Figure 1, only two magnetic components LF1 and LF2 (i.e., common-mode inductor LF1 and differential-mode inductor LF2) are required. The common-mode inductor LF1 can use a high-permeability iron core to reduce the number of winding turns, while the differential-mode inductor LF2 can use a low-permeability iron core to reduce its maximum magnetic flux density. The number of turns in the common-mode inductor LF1 and the differential-mode inductor LF2 can be the same, that is, the number of turns in the first winding N11 is the same as the number of turns in the second winding N12 and the number of turns in the third winding N13. Therefore, the hybrid noise filter of the first embodiment, based on current cancellation technology, can achieve a more efficient noise cancellation effect.

[0032] As shown in Figure 3, the current signs at each point in the circuit of the first embodiment are defined. Furthermore, as shown in Figure 4, the circuit of the first embodiment demonstrates the process of the circuit handling the differential-mode noise current iDM. It can be clearly seen from Figure 4 that when the differential-mode noise current iDM enters the winding of the common-mode inductor LF1, the magnetic lines of force generated by the first winding N11 and the second winding N12 cancel each other out, causing the common-mode inductor LF1 to have no effect on the differential-mode noise current iDM. Therefore, the differential-mode noise current iDM will completely pass through the common-mode inductor LF1 and enter the differential-mode inductor LF2, generating currents of the same magnitude but opposite directions in the first winding N21 and the second winding N22. The first winding N21 and the second winding N22 are connected in series with the differential-mode capacitor CX1, so it can be observed that the differential-mode noise current iDM, after being emitted from the noise source on the right, will flow back to that noise source. Therefore, the power supply impedance stabilization network 91 in Figure 4 will not detect differential mode noise current.

[0033] As shown in Figure 5, the circuit of the first embodiment illustrates the process of the circuit handling the common-mode noise current iCM / 2. It can be clearly seen from Figure 5 that when the common-mode noise current iCM / 2 enters the first winding N11 and the second winding N12 of the common-mode inductor LF1 from the live wire and neutral wire respectively, it generates a combined current iCM in the third winding N13, albeit in the same but opposite direction. Since the three windings of the common-mode inductor LF1 have the same number of turns, the current iN11 = the current iN13 / 2. The mapped current (=iCM / 2) generated by the second winding N12 in the third winding N13 then flows through the first winding N21 and the second winding N22 of the differential-mode inductor LF2 and then back to the third winding N13. Therefore, it can be observed that the combined current iCM, after being sent out from the noise source on the right, flows back to the noise source. Therefore, the power supply impedance stabilization network 91 in Figure 5 will not detect the common-mode noise current. Therefore, the hybrid noise filter designed in Figure 2 can eliminate both differential-mode noise current and common-mode noise current.

[0034] Please refer to Figure 6, which is a circuit diagram of a second embodiment of the hybrid noise filter of the present invention. Compared with the first embodiment shown in Figure 2, the common-mode filter unit 21 of the second embodiment shown in Figure 6 further includes a second common-mode capacitor CX2. The second common-mode capacitor CX2 is connected between the common-mode input sides. Specifically, the second common-mode capacitor CX2 has a first terminal and a second terminal. The first terminal of the second common-mode capacitor CX2 is connected to the first terminal of the third winding N13, and the second terminal of the second common-mode capacitor CX2 is connected to the first terminal of the second winding N12.

[0035] Following the description of the circuit architecture and processing of differential-mode and common-mode noise currents in the first embodiment of the hybrid noise filter in Figures 2-5, the second embodiment of the hybrid noise filter in Figure 6 can also achieve the elimination of differential-mode and common-mode noise currents. The relevant technical details will not be repeated here; please refer to the preceding content.

[0036] Please refer to Figure 7, which is a circuit diagram of the third embodiment of the hybrid noise filter of the present invention. The hybrid noise filter is coupled between the input power supply Vac and the power converter. Incidentally, the power converter is composed of all or part of a bridge rectifier 94, a voltage conversion circuit 95, a transformer 96, a protection circuit 97, and an output rectifier 98, but this is not intended to limit the present invention.

[0037] As shown in Figure 7, the hybrid noise filter includes a common-mode filter unit 31 and a differential-mode filter unit 41. The common-mode filter unit 31 has a common-mode input side (i.e., the input side of the common-mode filter unit 31) and a common-mode output side (i.e., the output side of the common-mode filter unit 31), wherein the common-mode input side is connected to the input power supply Vac, and more specifically, it is connected to the input power supply Vac through the power supply impedance stabilization network 91. The common-mode filter unit 31 includes a common-mode inductor LF1 and a first common-mode capacitor CY1. The common-mode inductor LF1 includes a first winding N11, a second winding N12, and a third winding N13. The first common-mode capacitor CY1 is connected in series with the third winding N13 and is connected to the ground terminal.

[0038] The differential-mode filter unit 41 has a differential-mode input side (i.e., the input side of the differential-mode filter unit 41) and a differential-mode output side (i.e., the output side of the differential-mode filter unit 41), and the differential-mode input side is connected to the common-mode output side, while the differential-mode output side is connected to the power converter. The differential-mode filter unit 41 includes a differential-mode inductor LF2 and a differential-mode capacitor CX1. The differential-mode inductor LF2 includes a first winding N21 and a second winding N22. The differential-mode capacitor CX1 is connected in series with the second winding N22.

[0039] Please refer to Figure 7. More specifically, the first winding N11 of the common-mode inductor LF1 has a first terminal and a second terminal, the second winding N12 of the common-mode inductor LF1 has a first terminal and a second terminal, the third winding N13 of the common-mode inductor LF1 has a first terminal and a second terminal, and the first common-mode capacitor CY1 has a first terminal and a second terminal. The first terminal of the first winding N11 is connected to the first terminal of the third winding N13, and the second terminal of the third winding N13 is connected to the first terminal of the first common-mode capacitor CY1. The first terminal of the first winding N11 and the first terminal of the second winding N12 form the common-mode input side. The second terminal of the first winding N11 and the second terminal of the second winding N12 form the common-mode output side.

[0040] Furthermore, the polarity of the second terminal of the first winding N11 of the common-mode inductor LF1 is the same as the polarity of the second terminal of the second winding N12 of the common-mode inductor LF1, and the polarity of the second terminal of the second winding N12 of the common-mode inductor LF1 is the same as the polarity of the second terminal of the third winding N13 of the common-mode inductor LF1. For example, in this embodiment, the second terminals of the first winding N11, the second winding N12, and the third winding N13 are all dotted polarities; conversely, the first terminals of the first winding N11, the second winding N12, and the third winding N13 are all undotted polarities.

[0041] Please refer to Figure 7. More specifically, the first winding N21 of the differential-mode inductor LF2 has a first terminal and a second terminal, the second winding N22 of the differential-mode inductor LF2 has a first terminal and a second terminal, and the differential-mode capacitor CX1 has a first terminal and a second terminal. The first terminal of the first winding N21 is connected to the first terminal of the second winding N22, and the second terminal of the second winding N22 is connected to the first terminal of the differential-mode capacitor CX1. The first terminal of the first winding N21 and the second terminal of the differential-mode capacitor CX1 form the differential-mode input side. The second terminal of the first winding N21 and the second terminal of the differential-mode capacitor CX1 form the differential-mode output side.

[0042] Furthermore, the polarity of the second terminal of the first winding N21 of the differential mode inductor LF2 is the same as the polarity of the second terminal of the second winding N22 of the differential mode inductor LF2. For example, in this embodiment, the second terminals of the first winding N21 and the second terminals of the second winding N22 are both dotted polarities; conversely, the first terminals of the first winding N21 and the first terminals of the second winding N22 are both undotted polarities.

[0043] Please refer to Figure 8, which is a circuit diagram of the fourth embodiment of the hybrid noise filter of the present invention. Compared with the third embodiment shown in Figure 7, the common-mode filter unit 31 of the fourth embodiment shown in Figure 8 further includes a second common-mode capacitor CX2. The second common-mode capacitor CX2 is connected between the common-mode input sides. Specifically, the second common-mode capacitor CX2 has a first terminal and a second terminal. The first terminal of the second common-mode capacitor CX2 is connected to the first terminal of the third winding N13, and the second terminal of the second common-mode capacitor CX2 is connected to the first terminal of the second winding N12.

[0044] Following the description of the circuit architecture and processing of differential-mode and common-mode noise currents in the first embodiment of the hybrid noise filter in Figures 2-5, the elimination of differential-mode and common-mode noise currents can also be achieved in the third embodiment of the hybrid noise filter in Figure 7 and the fourth embodiment of the hybrid noise filter in Figure 8. The relevant technical details will not be repeated here; please refer to the preceding content.

[0045] The above description is only a detailed description and drawings of preferred embodiments of the present invention. However, the features of the present invention are not limited thereto and are not intended to limit the present invention. The scope of the present invention should be determined by the following claims. All embodiments that are in line with the spirit of the claims and similar variations thereof should be included in the scope of the present invention. Any variations or modifications that can be easily conceived by those skilled in the art within the field of the present invention can be covered by the following claims. [Simplified Explanation of the Diagram]

[0046] Figure 1: is a circuit diagram of an existing switching power converter.

[0047] Figure 2: is a circuit diagram of the first embodiment of the hybrid noise filter of the present invention.

[0048] Figure 3: A schematic diagram of the current markings in Figure 2.

[0049] Figure 4: This is a schematic diagram of differential mode noise current processing in Figure 2.

[0050] Figure 5: This is a schematic diagram of the common-mode noise current processing in Figure 2.

[0051] Figure 6: is a circuit diagram of the second embodiment of the hybrid noise filter of the present invention.

[0052] Figure 7: is a circuit diagram of the third embodiment of the hybrid noise filter of the present invention.

[0053] Figure 8: is a circuit diagram of the first embodiment of the hybrid noise filter of the present invention.

Claims

1. A hybrid noise filter coupled between an input power supply and a power converter, the hybrid noise filter comprising: A differential-mode filter unit has a differential-mode input side and a differential-mode output side, with the differential-mode input side connected to the input power supply. The differential-mode filter unit includes: a differential-mode inductor, including a first winding and a second winding; and a differential-mode capacitor connected in series with the second winding of the differential-mode inductor. A common-mode filter unit has a common-mode input side and a common-mode output side, with the common-mode input side connected to the differential-mode output side and the common-mode output side connected to the power converter. The common-mode filter unit includes: a common-mode inductor, including a first winding, a second winding, and a third winding; and a first common-mode capacitor connected in series with the third winding of the common-mode inductor and connected to a ground terminal.

2. The hybrid noise filter as claimed in claim 1, wherein the first winding of the differential-mode inductor has a first terminal and a second terminal, the second winding of the differential-mode inductor has a first terminal and a second terminal, and the differential-mode capacitor has a first terminal and a second terminal; wherein the first terminal of the first winding is connected to the first terminal of the second winding, and the second terminal of the second winding is connected to the first terminal of the differential-mode capacitor; wherein the first terminal of the first winding and the second terminal of the differential-mode capacitor form the differential-mode input side; and wherein the second terminal of the first winding and the second terminal of the differential-mode capacitor form the differential-mode output side.

3. The hybrid noise filter as described in claim 2, wherein the polarity of the second terminal of the first winding of the differential mode inductor is the same as the polarity of the second terminal of the second winding of the differential mode inductor.

4. The hybrid noise filter as claimed in claim 1, wherein the first winding of the common-mode inductor has a first terminal and a second terminal, the second winding of the common-mode inductor has a first terminal and a second terminal, the third winding of the common-mode inductor has a first terminal and a second terminal, and the first common-mode capacitor has a first terminal and a second terminal; wherein the first terminal of the first winding is connected to the first terminal of the third winding, and the second terminal of the third winding is connected to the first terminal of the first common-mode capacitor; wherein the first terminal of the first winding and the first terminal of the second winding form the common-mode input side; and wherein the second terminal of the first winding and the second terminal of the second winding form the common-mode output side.

5. The hybrid noise filter as claimed in claim 4, wherein the polarity of the second terminal of the first winding of the common-mode inductor is the same as the polarity of the second terminal of the second winding of the common-mode inductor, and the polarity of the second terminal of the second winding of the common-mode inductor is the same as the polarity of the second terminal of the third winding of the common-mode inductor.

6. The hybrid noise filter as described in claim 1, wherein the common-mode filtering unit further comprises: A second common-mode capacitor is connected between the common-mode input sides.

7. The hybrid noise filter as described in claim 4, wherein the common-mode filtering unit further comprises: A second common-mode capacitor has a first terminal and a second terminal; wherein the first terminal of the second common-mode capacitor is connected to the first terminal of the third winding, and the second terminal of the second common-mode capacitor is connected to the first terminal of the second winding.

8. A hybrid noise filter coupled between an input power supply and a power converter, the hybrid noise filter comprising: A common-mode filter unit has a common-mode input side and a common-mode output side, and the common-mode input side is connected to the input power supply. The common-mode filter unit includes: a common-mode inductor including a first winding, a second winding, and a third winding; and a first common-mode capacitor connected in series with the third winding of the common-mode inductor and connected to a ground terminal; and a differential-mode filter unit has a differential-mode input side and a differential-mode output side, the differential-mode input side is connected to the common-mode output side, and the differential-mode output side is connected to the power converter. The differential-mode filter unit includes: a differential-mode inductor including a first winding and a second winding; and a differential-mode capacitor connected in series with the second winding of the differential-mode inductor.

9. The hybrid noise filter as claimed in claim 8, wherein the first winding of the common-mode inductor has a first terminal and a second terminal, the second winding of the common-mode inductor has a first terminal and a second terminal, the third winding of the common-mode inductor has a first terminal and a second terminal, and the first common-mode capacitor has a first terminal and a second terminal; wherein the first terminal of the first winding is connected to the first terminal of the third winding, and the second terminal of the third winding is connected to the first terminal of the first common-mode capacitor; wherein the first terminal of the first winding and the first terminal of the second winding form the common-mode input side; and wherein the second terminal of the first winding and the second terminal of the second winding form the common-mode output side.

10. The hybrid noise filter as claimed in claim 9, wherein the polarity of the second terminal of the first winding of the common-mode inductor is the same as the polarity of the second terminal of the second winding of the common-mode inductor, and the polarity of the second terminal of the second winding of the common-mode inductor is the same as the polarity of the second terminal of the third winding of the common-mode inductor.

11. The hybrid noise filter as claimed in claim 8, wherein the first winding of the differential-mode inductor has a first terminal and a second terminal, the second winding of the differential-mode inductor has a first terminal and a second terminal, and the differential-mode capacitor has a first terminal and a second terminal; wherein the first terminal of the first winding is connected to the first terminal of the second winding, and the second terminal of the second winding is connected to the first terminal of the differential-mode capacitor; wherein the first terminal of the first winding and the second terminal of the differential-mode capacitor form the differential-mode input side; and wherein the second terminal of the first winding and the second terminal of the differential-mode capacitor form the differential-mode output side.

12. The hybrid noise filter as claimed in claim 11, wherein the polarity of the second terminal of the first winding of the differential mode inductor is the same as the polarity of the second terminal of the second winding of the differential mode inductor.

13. The hybrid noise filter as described in claim 8, wherein the common-mode filtering unit further comprises: A second common-mode capacitor is connected between the common-mode input sides.

14. The hybrid noise filter as described in claim 9, wherein the common-mode filtering unit further comprises: A second common-mode capacitor has a first terminal and a second terminal; wherein the first terminal of the second common-mode capacitor is connected to the first terminal of the third winding, and the second terminal of the second common-mode capacitor is connected to the first terminal of the second winding.

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