A magnetic integrated inductor and its fabrication method, and a dual-channel interleaved PFC circuit.

Abstract

This invention discloses a magnetically integrated inductor and its fabrication method, as well as a dual-channel interleaved PFC circuit. The magnetically integrated inductor includes a first inductor and a second inductor; the first inductor and the second inductor are integrated to form a magnetically integrated coupled inductor; the first inductor includes a first magnetic core and a first coil; the second inductor includes a second magnetic core and a second coil; wherein the first coil is wound on the first magnetic core to form the first inductor; the second coil is wound on the second magnetic core to form the second inductor; the first magnetic core and the second magnetic core are integrated on a single magnetic core structure. This solution reduces the inductor volume of the two PFC circuits by integrating the two independent inductors of the two-channel PFC circuit into a single coupled inductor.

Description

Technical Field

[0001] This invention belongs to the field of electronic circuit technology, specifically relating to a magnetic integrated inductor and its manufacturing method, a dual-channel interleaved PFC circuit, and more particularly to a magnetic integrated inductor for a dual-channel interleaved PFC circuit and its manufacturing method, as well as a dual-channel interleaved PFC circuit having the magnetic integrated inductor. Background Technology

[0002] A dual-path interleaved parallel PFC (Power Factor Correction) circuit consists of two PFC circuits connected in parallel at a 180-degree interval. In related schemes, the two PFC circuits use two independent inductors, and the inductors account for a large proportion of the circuit volume, thus increasing the circuit size.

[0003] The above content is only used to help understand the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0004] The purpose of this invention is to provide a magnetic integrated inductor and its manufacturing method, as well as a dual-channel interleaved PFC circuit, to solve the problem that using two independent inductors in two-channel PFC circuits results in a large inductor volume. By integrating the two independent inductors of the two-channel PFC circuits into a single coupled inductor, the inductor volume of the two-channel PFC circuits can be reduced.

[0005] The present invention provides a magnetically integrated inductor, comprising: a first inductor and a second inductor; the first inductor and the second inductor are integrated to form a magnetically integrated coupled inductor.

[0006] In some embodiments, the first inductor includes a first magnetic core and a first coil; the second inductor includes a second magnetic core and a second coil; wherein the first coil is wound around the first magnetic core to form the first inductor; the second coil is wound around the second magnetic core to form the second inductor; the first magnetic core and the second magnetic core are integrated on a single magnetic core structure.

[0007] In some embodiments, the first magnetic core is E-shaped; the first coil is formed by winding the same phase winding around different core pillars of the first magnetic core; the second magnetic core is either E-shaped or I-shaped; when the second magnetic core is E-shaped, the second coil is formed by winding the same phase winding around different core pillars of the second magnetic core; when the second magnetic core is I-shaped, the second coil is formed by winding the same phase winding around different core pillars of the first magnetic core, and there is no winding on the core pillars of the second magnetic core.

[0008] In some embodiments, the coupling direction of the first coil when it is wound on the first magnetic core and the coupling direction of the second coil when it is wound on the second magnetic core are either forward coupling directions or reverse coupling directions.

[0009] In some embodiments, when the first magnetic core is E-shaped, the first coil is wound on the side posts of the first magnetic core, and there is no winding on the middle post of the first magnetic core; when the second magnetic core is E-shaped, the second coil is wound on the side posts of the second magnetic core, and there is no winding on the middle post of the second magnetic core; when the second magnetic core is I-shaped, the second coil is wound on the side posts of the first magnetic core, and there is no winding on the middle post of the first magnetic core; or, when the second magnetic core is I-shaped, the second coil is formed by winding the same phase winding on different core posts of the first magnetic core, and there is no winding on the core post of the second magnetic core.

[0010] In some implementations, the number of turns of each phase winding on different core posts is different in the first coil and the second coil.

[0011] In some embodiments, the air gap length is the same for all core posts of the first magnetic core and for different core posts of the second magnetic core.

[0012] In conjunction with the above-described device, the present invention further provides a dual-channel interleaved PFC circuit, comprising: the magnetic integrated inductor described above.

[0013] In conjunction with the aforementioned dual-channel interleaved PFC circuit, this invention further provides a method for manufacturing a magnetic integrated inductor, comprising: determining a first inductance parameter of a first inductor and a second inductance parameter of a second inductor according to a set specification; manufacturing the first inductor according to the first inductance parameter of the first inductor; manufacturing the second inductor according to the second inductance parameter of the second inductor; and integrating the first magnetic core of the first inductor and the second magnetic core of the second inductor onto a single magnetic core structure to form the magnetic integrated inductor.

[0014] In some embodiments, the inductance parameters in the first and second inductance parameters include at least one of the following: coupling factor, self-inductance, winding wire diameter, core size, number of winding turns, core window area, and air gap length.

[0015] Therefore, the present invention integrates two independent inductors into a single coupled inductor, replacing the two independent inductors of the two PFC circuits with this coupled inductor; thus, by integrating the two independent inductors of the two PFC circuits into a single coupled inductor, the inductor volume of the two PFC circuits can be reduced.

[0016] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention.

[0017] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of an embodiment of the magnetic integrated inductor of the present invention;

[0019] Figure 2 This is a schematic diagram of an embodiment of a magnetic integrated inductor; wherein, (a) is a schematic diagram of the magnetic integrated inductor with EE-type magnetic core in forward coupling, (b) is a schematic diagram of the magnetic integrated inductor with EE-type magnetic core in reverse coupling, (c) is a schematic diagram of the magnetic integrated inductor with EI-type magnetic core in forward coupling, and (d) is a schematic diagram of the magnetic integrated inductor with EI-type magnetic core in reverse coupling;

[0020] Figure 3 A schematic diagram of the magnetic circuit structure of an embodiment of a magnetic integrated inductor;

[0021] Figure 4 The diagram shows the magnetic flux waveforms of the middle column and the side column of a forward-coupled magnetic integrated inductor; where (a) is a schematic diagram of the magnetic flux waveforms of the middle column and the side column when the duty cycle is greater than 0 and less than or equal to 0.5, and (b) is a schematic diagram of the magnetic flux waveforms of the middle column and the side column when the duty cycle is greater than 0.5 and less than 1.

[0022] Figure 5 The diagram shows the magnetic flux waveforms of the middle column and the side column of a reverse-coupled magnetic integrated inductor; where (a) is a schematic diagram of the magnetic flux waveforms of the middle column and the side column when the duty cycle is greater than 0 and less than or equal to 0.5, and (b) is a schematic diagram of the magnetic flux waveforms of the middle column and the side column when the duty cycle is greater than 0.5 and less than 1.

[0023] Figure 6 This is a schematic diagram illustrating the fabrication process of an embodiment of a magnetic integrated inductor.

[0024] Figure 7 This is a schematic flowchart of an embodiment of the method for manufacturing a magnetic integrated inductor of the present invention;

[0025] Figure 8This is a schematic diagram of the structure of the first magnetic core and the second magnetic core in the magnetic integrated inductor of the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0027] According to an embodiment of the present invention, a magnetically integrated inductor is provided. See also Figure 1 The diagram shows a structural schematic of an embodiment of the device of the present invention. The magnetically integrated inductor may include a first inductor and a second inductor. The first inductor and the second inductor are integrated to form a magnetically integrated coupled inductor.

[0028] Specifically, by integrating two independent inductors into a single coupled inductor (i.e., a magnetically integrated coupled inductor), the size of the inductor is reduced, thus solving the problem of large inductor size.

[0029] In some embodiments, the first inductor includes a first magnetic core and a first coil. The second inductor includes a second magnetic core and a second coil.

[0030] The first coil is wound around the first magnetic core to form the first inductor. The second coil is wound around the second magnetic core to form the second inductor. The first and second magnetic cores are integrated into a single magnetic core structure.

[0031] Therefore, by integrating two magnetic elements onto a single magnetic core structure to form a magnetically integrated inductor for a dual-path interleaved PFC circuit, the voltage and current relationships of each magnetic element in the circuit topology, as well as the magnetic flux and magnetomotive force relationships in the magnetic circuit topology, are fully utilized. This integration of the two magnetic elements reduces the size of the magnetic device, improves input and inductor current ripple, and enhances the transient response speed of the power supply. Consequently, it can reduce losses, increase power density, and ensure power supply output stability.

[0032] In some embodiments, the first magnetic core is E-shaped. The first coil is formed by winding the same phase winding around different core posts of the first magnetic core.

[0033] The second magnetic core has an E-type or I-type shape. When the second magnetic core is E-type, the second coil is formed by winding the same phase winding around different core pillars of the second magnetic core. When the second magnetic core is I-type, the second coil is formed by winding the same phase winding around different core pillars of the first magnetic core, and there is no winding on the core pillars of the second magnetic core.

[0034] Therefore, by winding the same phase winding on different magnetic core pillars, the coupling factor of forward or reverse coupling can be increased, thereby further reducing the input current ripple or inductor current ripple. That is, the input current ripple is further reduced during forward coupling or the inductor current ripple is further reduced during reverse coupling, which can solve the problem of large input current ripple or inductor current ripple and improve the circuit efficiency of the two-way PFC circuit.

[0035] In some embodiments, the coupling direction of the first coil when it is wound on the first magnetic core and the coupling direction of the second coil when it is wound on the second magnetic core are either forward coupling directions or reverse coupling directions.

[0036] Specifically, the magnetic core adopts a shape similar to EE or EI, and the material can be soft magnetic ferrite. The air gap length of the three core pillars is the same. EE consists of two E-type magnetic cores forming a magnetic circuit, while EI consists of E-type and I-type magnetic cores forming a magnetic circuit. The winding method of the two-phase winding can be divided into forward coupling winding method or reverse coupling winding method.

[0037] In some embodiments, when the first magnetic core is E-shaped, the first coil is wound on the side posts of the first magnetic core, and there is no winding on the center post of the first magnetic core.

[0038] When the second magnetic core is E-shaped, the second coil is wound on the side post of the second magnetic core, and there is no winding on the middle post of the second magnetic core.

[0039] When the second magnetic core is I-shaped, in the first magnetic core and the second coil, the second coil is wound on the side post of the first magnetic core, and there is no winding on the middle post of the first magnetic core; or, when the second magnetic core is I-shaped, in the second magnetic core and the second coil, the second coil is formed by winding the same phase winding on different core posts of the first magnetic core, and there is no winding on the core post of the second magnetic core.

[0040] In some implementations, the number of turns of each phase winding on different core posts is different in the first coil and the second coil.

[0041] Specifically, the windings of each phase are wound on both side posts of the magnetic core, and the total number of turns of the windings of each phase is N+N' (assuming N is greater than N'), while there are no windings on the middle post of the magnetic core. Therefore, the coupling factor of this type of magnetic integrated inductor can be greater than or equal to one-third.

[0042] In some embodiments, the air gap length is the same for all core posts of the first magnetic core and the second magnetic core. By making the air gap length of each core post the same, it is not necessary to cut the magnetic core, thus making the manufacturing of the magnetic integrated inductor simpler and more convenient.

[0043] Extensive testing has verified that the technical solution of this invention integrates two independent inductors into a single coupled inductor, replacing the two independent inductors in two PFC circuits. Therefore, by integrating the two independent inductors of the two PFC circuits into a single coupled inductor, the inductor size of the two PFC circuits can be reduced.

[0044] According to an embodiment of the present invention, a dual-channel interleaved PFC circuit corresponding to a magnetic integrated inductor is also provided. This dual-channel interleaved PFC circuit may include the magnetic integrated inductor described above.

[0045] In a dual-channel interleaved parallel PFC circuit, the two PFC circuits operate in parallel with a 180-degree gap. The input current of the two PFC circuits is the sum of the inductor currents of the two PFC circuits. Because the inductor currents are not in phase, they cancel each other out and reduce the input current ripple, thereby improving efficiency and stability.

[0046] In the relevant solutions, when integrating the inductors of the two PFC circuits, it is necessary to cut the two magnetic cores according to different requirements. The operation process is cumbersome, and the applicable range of the cut magnetic cores is limited.

[0047] For example, in related solutions, reverse coupling is used to improve the rate of current drop in the inductor, thereby reducing the current ripple of the inductor coil, i.e., reducing the effective and peak values ​​of the inductor current. The solution of this invention employs both reverse and forward coupling. Reverse coupling can improve inductor current ripple, while forward coupling can improve input current ripple. The appropriate coupling method can be selected based on specific requirements.

[0048] In related solutions, a specially made magnetic core is used, and the material is ferrite. The solution of this invention does not use a specially made magnetic core, but rather a common E-type or I-type magnetic core, such as... Figure 8 As shown, the base plate is a rectangular structure, the two side pillars are rectangular or approximately rectangular pillars, and the central pillar is a rectangular, elliptical, or circular pillar. This use of a universal magnetic core structure saves on procurement costs.

[0049] In related solutions, two coils are wound around two side posts to form two inductor coils. There are multiple air gaps on the side posts and multiple air gaps on the center post. The sum of the lengths of the multiple first air gaps is less than the sum of the lengths of the multiple second air gaps; that is, the total air gap length of the side posts is less than the total air gap length of the center post. At this point, a single-sided inductor coil will not saturate. Since the magnetic core is specially made, the length of the center post is already less than the length of the side posts during manufacturing, so the magnetic core does not need to be cut. However, if a commercially available magnetic core is used, the core needs to be cut again to make the total air gap length of the side posts less than the total air gap length of the center post. The solution of this invention also has two inductor coils, but each inductor coil is wound around two side posts, instead of one inductor coil being wound around only one side post. The total air gap length of the side posts is equal to the total air gap length of the center post. Thus, air gaps can be formed simply by adding air gap spacers without cutting the magnetic core. The air gap spacers are made of non-magnetic insulating material.

[0050] Furthermore, the relevant plan did not provide the manufacturing method and steps.

[0051] In some embodiments, the present invention proposes a magnetically integrated inductor for a dual-channel interleaved PFC circuit, which integrates two independent inductors into a single coupled inductor (i.e., a magnetically integrated coupled inductor), thereby reducing the inductor size and solving the problem of large inductor size.

[0052] Furthermore, the present invention improves the coupling factor of forward or reverse coupling by winding the same phase winding on different magnetic core pillars, thereby further reducing the input current ripple or inductor current ripple. That is, it further reduces the input current ripple during forward coupling or the inductor current ripple during reverse coupling, thus solving the problem of large input current ripple or inductor current ripple and improving the circuit efficiency of the two PFC circuits. At the same time, it makes the air gap length of each magnetic core pillar the same, eliminating the need to cut the magnetic core, thus making the manufacturing of the magnetic integrated inductor simpler and more convenient.

[0053] Thus, the solution of this invention integrates two magnetic elements (such as a first magnetic core and a second magnetic core) onto a single magnetic core structure (such as a magnetic core formed by integrating the first and second magnetic cores) to form a magnetically integrated inductor for a dual-path interleaved PFC circuit. This fully utilizes the voltage and current relationships of each magnetic element in the circuit topology, as well as the magnetic flux and magnetomotive force relationships in the magnetic circuit topology, to achieve the integration of the two magnetic elements. This reduces the size of the magnetic device, improves the input and inductor current ripple, and enhances the transient response speed of the power supply. Consequently, it can reduce losses, increase power density, and ensure the stability of the power supply output.

[0054] In a circuit, self-inductance and coupling factor have corresponding formulas relating to voltage and current. Similarly, in a magnetic circuit, self-inductance and coupling factor have corresponding formulas relating to magnetic flux and magnetomotive force. Therefore, through self-inductance and coupling factor, magnetic circuits and electrical circuits can be linked, thereby enabling the design and integration of magnetic components based on the characteristics of the circuit.

[0055] The following is combined with Figures 2 to 6 The examples shown illustrate the specific implementation process of the solution of the present invention.

[0056] Figure 2 This is a schematic diagram of one embodiment of a magnetic integrated inductor; wherein, (a) is a schematic diagram of the magnetic integrated inductor with EE-type magnetic core forward coupling, (b) is a schematic diagram of the magnetic integrated inductor with EE-type magnetic core reverse coupling, (c) is a schematic diagram of the magnetic integrated inductor with EI-type magnetic core forward coupling, and (d) is a schematic diagram of the magnetic integrated inductor with EI-type magnetic core reverse coupling. Figure 2 As shown, the magnetic core adopts a shape similar to EE or EI, and the material can be soft magnetic ferrite. The air gap length of the three core pillars is the same. EE consists of two E-type magnetic cores forming a magnetic circuit, while EI consists of E-type and I-type magnetic cores forming a magnetic circuit. The winding method of the two-phase winding can be divided into... Figure 2 The EE-type magnetic core shown in (a) is a forward-coupled winding method. Figure 2 The reverse coupling winding method of the EE type magnetic core shown in (b) is as follows: Figure 2 The EI type magnetic core shown in (c) is a forward-coupled winding method. Figure 2 The EI type magnetic core shown in (d) is a reverse coupling winding method.

[0057] exist Figure 2 In the example shown, the winding of each phase is wound on both side posts of the magnetic core, and the total number of turns of the winding of each phase is N+N' (assuming N is greater than N'), while there is no winding on the middle post of the magnetic core. Therefore, the coupling factor of this type of magnetic integrated inductor can be greater than or equal to one-third.

[0058] Figure 3 This is a schematic diagram of the magnetic circuit structure of one embodiment of a magnetic integrated inductor. Figure 3 As shown, the magnetic circuit corresponding to the integrated magnetic inductor includes: a magnetoresistive resistor Rc and two magnetoresistive resistors Ro, and a magnetomotive force Ni. L1 Magnetomotive force N'i L1 Magnetomotive force ρN'i L2 and magnetomotive force ρNi L2 Magnetomotive force Ni L1 The positive terminal is connected to the magnetomotive force N'i. L1 The negative terminal is also connected to the magnetomotive force ρN'i via the magnetic reluctance Rc. L2 The negative pole and magnetomotive force ρNiL2 The positive terminal. ρ = 1 indicates forward coupling, ρ = -1 indicates reverse coupling. Magnetomotive force Ni L1 The negative terminal, after passing through a magnetic reluctance Ro, is connected to the magnetomotive force ρN'i. L2 The positive pole. Magnetomotive force N'i L1 The positive terminal, after passing through another magnetic reluctance Ro, is connected to the magnetomotive force ρNi. L2 The negative electrode. Φ 01 Φ 02 Φ c is the magnetic flux.

[0059] Figure 4 The diagram shows the magnetic flux waveforms of the middle column and the side column of a forward-coupled magnetic integrated inductor; where (a) is a schematic diagram of the magnetic flux waveforms of the middle column and the side column when the duty cycle is greater than 0 and less than or equal to 0.5, and (b) is a schematic diagram of the magnetic flux waveforms of the middle column and the side column when the duty cycle is greater than 0.5 and less than 1. Figure 5 The diagrams show the magnetic flux waveforms of the middle and side columns of a reverse-coupled magnetic integrated inductor; where (a) is a schematic diagram of the magnetic flux waveforms of the middle and side columns when the duty cycle is greater than 0 and less than or equal to 0.5, and (b) is a schematic diagram of the magnetic flux waveforms of the middle and side columns when the duty cycle is greater than 0.5 and less than 1. Figure 4 and Figure 5 In this circuit, Ts is the switching cycle of the two-way interleaved PFC circuit, Q1 and Q2 are two switches in the two-way interleaved PFC circuit, and D is the duty cycle.

[0060] Through the Figure 3 By analyzing the magnetic circuit corresponding to the magnetic integrated inductor shown, we can obtain... Figure 4 and Figure 5 The magnetic flux waveforms of the integrated magnetic inductor shown indicate that the magnetic induction intensity is greatest at the core side posts in both forward and reverse coupling. Therefore, the design should be based on the magnetic induction intensity of the core side posts to ensure that the core side posts are not saturated.

[0061] In the present invention, regarding the magnetic integrated structure, since the designed integrated magnetic components are used for a specific circuit, the magnetic integrated structure does not have a fixed form. First, based on the specific circuit topology, it is necessary to determine what kind of magnetic integrated structure can achieve the function of the specific circuit. Therefore, it is important not only to consider the requirements of the specific circuit during the design process, but also to analyze the integrated magnetic components after the design is completed. Furthermore, the selection of the integrated structure must comprehensively consider its impact on iron losses and current ripple to optimize circuit performance, thereby selecting the best from various magnetic integrated structure options.

[0062] For example, existing magnetically integrated inductors in related solutions initially had a non-coupled structure, where the two phase inductor coils were wound on two different side posts, with no air gap in the center post and air gaps on the two side posts, forming a magnetically integrated non-coupled dual inductor. Considering that coupled inductors can optimize current ripple and improve efficiency compared to non-coupled inductors, some similar magnetically integrated coupled inductors later appeared, where the center post has an air gap, and the length of the air gap between the center post and the two side posts is different. However, if a general-purpose magnetic core is used, this would inevitably require cutting the core, leading to a cumbersome operation process, and the applicability of the cut core is limited. Therefore, the inventors of this invention considered whether there was a way to achieve the effect of a magnetically integrated coupled inductor without cutting the magnetic core, and came up with the method of winding each phase coil on different side posts. This allows the air gaps of each core post to be the same, and the air gaps are formed by adding air gap shims, while still maintaining the same magnetically integrated coupled inductor. Then, the specific circuit and magnetic integrated structure are analyzed to determine the specific design method. The main difficulties are determining the magnetic integrated structure and the design method.

[0063] In the solution of this invention, a set of... was determined through analysis of the circuit and magnetic circuit. Figure 6 The inductor design and manufacturing process is shown, and the parameter calculation method is summarized, thus solving the difficulty in selecting parameters such as core type, air gap size, and wire specifications.

[0064] Figure 6 This is a schematic diagram illustrating the fabrication process of one embodiment of a magnetic integrated inductor. Figure 6 As shown, the fabrication process of a magnetic integrated inductor includes:

[0065] Step 1: Specify the specifications.

[0066] For example, the parameters given mainly include minimum input voltage, maximum input voltage, output voltage, maximum output power, efficiency, switching frequency, input current ripple and inductor current ripple range at minimum input voltage and full load, maximum magnetic flux density, maximum current density, and core window utilization.

[0067] Step 2: Determine the coupling factor and self-inductance.

[0068] The coupling factor and self-inductance can be determined based on the input current ripple and inductor current ripple ranges required in the design specifications.

[0069] Step 3: Determine the winding wire diameter. Winding cross-sectional area A w It can be determined as follows:

[0070] A w ≥I Lrms / J max .

[0071] Using the calculated Aw You can select a suitable wire diameter from the winding selection table. Among them, I... Lrms J is the effective value of the inductor current; max This represents the maximum current density.

[0072] Step 4: Determine the core size using the AP method. The AP method is used for selection; the AP expression is shown below:

[0073] AP = 2 × 10 4 (1+α)I Lrms (φ dc +Δφ) / J max K u cm 4 .

[0074] Where α is the scaling factor between the number of turns N and N', i.e.

[0075]

[0076] φ dc K is the DC magnetic flux of the side pillar, Δφ is the ripple magnetic flux of the side pillar, and K is the DC magnetic flux of the side pillar. u This is the core window utilization factor.

[0077] Step 5: Determine the number of turns in the winding. N can be calculated using the formula N = (φ dc +Δφ) / (B max A eo The calculation is performed using the formula N' = αN, and N' can then be calculated.

[0078] Among them, B max A is the maximum flux density of the side pillar. eo Let be the cross-sectional area of ​​the magnetic core side post.

[0079] Step 6: Determine if the winding area is suitable for the core window area. If yes, proceed to Step 7; otherwise, select a larger core and return to Step 5. Use the following formula:

[0080] (N+N')A w ≤K u W a .

[0081] If the above formula is not met, a larger magnetic core should be selected. Where W... a Let be the area of ​​a window in the magnetic core.

[0082] Step 7: Determine the air gap length.

[0083] Neglecting the core reluctance and the edge effects of the air gap magnetic field, the air gap length l g It can be approximated as:

[0084] l g =(3N) 2 +2NN'+3N' 2 )μ o A eo / (4L s ).

[0085] Where: μ o L is the permeability in vacuum. s For self-perception.

[0086] In the solution of this invention, regarding the magnetic integration design, the structure of integrated magnetic components differs from that of typical discrete magnetic components, thus presenting certain challenges in selecting parameters such as core type, air gap size, and wire specifications. Related solutions lack universal parameter calculation methods, and designers typically determine the design scheme and manufacturing process based on actual requirements.

[0087] See Figure 6 In the example shown, by selecting a large absolute value for the coupling factor in the design of the magnetic integrated inductor, the input current ripple can be reduced when using forward coupling, and the inductor current ripple can be reduced when using reverse coupling. Simultaneously, the air gap lengths of the three core pillars are the same, avoiding core cutting, simplifying the manufacturing process, and reducing labor time. The core size is selected using the derived AP method (area product method) formula for this type of magnetic integrated inductor structure, thus ensuring that the core will not saturate during circuit operation.

[0088] In summary, the solution of this invention integrates independent inductors into a magnetically integrated coupled inductor, rather than integrating independent inductors into a magnetically integrated independent inductor. Compared with independent inductors, coupled inductors can reduce input current ripple when using forward coupling with a large coupling factor, and can reduce inductor current ripple when using reverse coupling with a large coupling factor, thus improving circuit efficiency.

[0089] Since the processing and functions implemented by the dual-interleaved PFC circuit in this embodiment are basically the same as those described above... Figure 1 The embodiments, principles, and examples of the device shown are as follows. Therefore, for any details not covered in the description of this embodiment, please refer to the relevant descriptions in the foregoing embodiments, which will not be repeated here.

[0090] Through extensive testing and verification, the technical solution of this invention integrates two independent inductors into a single coupled inductor. This coupled inductor replaces the two independent inductors in the two PFC circuits, reducing the size of the magnetic components, improving input and inductor current ripple, and increasing the power supply transient response speed.

[0091] According to embodiments of the present invention, a method for fabricating a magnetically integrated inductor corresponding to a dual-channel interleaved PFC circuit is also provided, such as... Figure 7 The diagram shows a flowchart of an embodiment of the method of the present invention. The method for manufacturing this magnetic integrated inductor may include steps S110 to S130.

[0092] In step S110, the first inductance parameter of the first inductor and the second inductance parameter of the second inductor are determined according to the set specifications.

[0093] In step S120, the first inductor is manufactured according to the first inductance parameters of the first inductor. The second inductor is manufactured according to the second inductance parameters of the second inductor.

[0094] In step S130, the first magnetic core of the first inductor and the second magnetic core of the second inductor are integrated on a single magnetic core structure to form the magnetically integrated inductor.

[0095] Specifically, by integrating independent inductors into magnetically coupled inductors, the input current ripple can be reduced when using forward coupling with a large coupling factor, and the inductor current ripple can be reduced when using reverse coupling with a large coupling factor, thus making the circuit more efficient.

[0096] In some embodiments, the inductance parameters in the first and second inductance parameters include at least one of the following: coupling factor, self-inductance, winding wire diameter, core size, number of winding turns, core window area, and air gap length.

[0097] Specifically, by selecting a large absolute value for the coupling factor in the design of the magnetic integrated inductor, the input current ripple can be reduced when using forward coupling, while the inductor current ripple can be reduced when using reverse coupling. Simultaneously, the air gap lengths of the three core pillars are identical, avoiding core cutting, simplifying the manufacturing process, and reducing labor time. The core size is selected using the derived AP method (area product method) formula for this type of magnetic integrated inductor structure, thus ensuring that the core will not saturate during circuit operation.

[0098] Since the processing and functions implemented by the method in this embodiment are basically the same as the embodiments, principles and examples of the aforementioned magnetic integrated inductors, any details not covered in this embodiment can be found in the relevant descriptions in the aforementioned embodiments, and will not be repeated here.

[0099] Extensive testing has verified that the technical solution of this embodiment, by integrating two independent inductors into a single coupled inductor and replacing the two independent inductors in the two PFC circuits with this coupled inductor, can reduce losses, increase power density, and ensure power output stability.

[0100] In summary, it is readily understood by those skilled in the art that, without conflict, the aforementioned advantageous methods can be freely combined and superimposed.

[0101] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A method for manufacturing a magnetic integrated inductor, characterized in that, The magnetically integrated inductor includes: a first inductor and a second inductor; the first inductor and the second inductor are integrated to form a magnetically integrated coupled inductor; the first inductor includes: a first magnetic core and a first coil; the second inductor includes: a second magnetic core and a second coil; wherein, The first coil is wound on the first magnetic core to form the first inductor; the second coil is wound on the second magnetic core to form the second inductor; the first magnetic core and the second magnetic core are integrated on a single magnetic core structure; in the first coil and the second coil, the number of turns of each phase winding on different core columns is different; two independent inductors are integrated into a single coupled inductor, which is used to replace the two independent inductors of the two PFC circuits; The method for manufacturing the magnetic integrated inductor includes: Based on the set specifications, the first inductance parameters of the first inductor and the second inductance parameters of the second inductor are determined. Specifically, a large absolute value of the coupling factor is selected for the design of the magnetic integrated inductor, and the core size is selected using the AP method calculation formula for magnetic integrated inductors. The set specifications include: minimum input voltage, maximum input voltage, output voltage, maximum output power, efficiency, switching frequency, input current ripple and inductor current ripple range at minimum input voltage and full load, maximum magnetic flux density, maximum current density, and core window utilization. The AP method calculation formula is as follows: AP =2×10 4 (1+ α ) I Lrms ( dc +D ) / J max K u cm 4 ; in, α The scaling factor for the number of turns N and N' is... ； dc Let Δ be the DC magnetic flux of the side column. For the ripple flux of the side pillar, K u This is the core window utilization factor. I Lrms This is the effective value of the inductor current; J max The maximum current density is denoted by N and N', which are the number of turns of the windings of each phase wound on the side posts of the first and second magnetic cores. The number of turns of the windings wound on the side posts of the corresponding magnetic cores of the first and second inductors are different. ρ = 1 indicates forward coupling, and ρ = -1 indicates reverse coupling. Determine the number of turns in the winding N， Utilization N =( dc +Δ ) / ( B max A eo ) Perform calculations using the formula N' = αN , N’ It was calculated; among which, B max The maximum flux density of the side pillar. A eo Let be the cross-sectional area of ​​the magnetic core's side pillars; Determine if the winding area is suitable for the core window area. If so, determine the air gap length; otherwise, select a larger core. Use the following formula: ( N + N’ ) A w ≤ K u W a , W a This represents the area of ​​a window in the magnetic core. A w Where is the cross-sectional area of ​​the winding, and Ku is the core window utilization factor; Determine the air gap length. l g Represented as: In the formula: μ o Permeability in vacuum L s For self-perception; The first inductor is manufactured according to the first inductance parameters of the first inductor; the second inductor is manufactured according to the second inductance parameters of the second inductor. The first magnetic core of the first inductor and the second magnetic core of the second inductor are integrated on a single magnetic core structure to form the magnetically integrated inductor.

2. The method for manufacturing a magnetic integrated inductor according to claim 1, characterized in that, in, The first magnetic core is E-shaped; the first coil is formed by winding the same phase winding around different core pillars of the first magnetic core. The second magnetic core is E-shaped; When the second magnetic core is of shape E, the second coil is formed by winding the same phase winding on different core pillars of the second magnetic core.

3. The method for manufacturing a magnetic integrated inductor according to claim 2, characterized in that, The coupling direction of the first coil when it is wound on the first magnetic core and the coupling direction of the second coil when it is wound on the second magnetic core are either forward coupling directions or reverse coupling directions.

4. The method for manufacturing a magnetic integrated inductor according to claim 2, characterized in that, When the shape of the first magnetic core is E-type, in the first magnetic core and the first coil, the first coil is wound on the side post of the first magnetic core, and there is no winding on the middle post of the first magnetic core; When the second magnetic core is E-shaped, the second coil is wound on the side post of the second magnetic core, and there is no winding on the middle post of the second magnetic core.

5. The method for manufacturing a magnetic integrated inductor according to claim 2, characterized in that, In the different core posts of the first magnetic core and the different core posts of the second magnetic core, all core posts have the same air gap length.

6. The method for manufacturing a magnetic integrated inductor according to claim 1, characterized in that, The inductance parameters in the first and second inductance parameters include at least one of the following: coupling factor, self-inductance, winding wire diameter, core size, number of winding turns, core window area, and air gap length.

7. A dual-channel interleaved PFC circuit, characterized in that, include: A magnetic integrated inductor manufactured by the method for manufacturing a magnetic integrated inductor as described in any one of claims 1 to 6.

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