Integrated magnetic component and switching power supply

Abstract

The application discloses an integrated magnetic component, comprising a magnetic core and a PCB winding, the PCB winding comprises a primary winding and a plurality of secondary windings, the magnetic core comprises a magnetic column, a top cover and a bottom cover, the magnetic column of the magnetic core comprises a middle column and side columns arranged on both sides of the middle column, the primary winding is wound on the middle column, and the secondary winding is wound outside the middle column and one side column and does not pass between the two, so that fractional turn winding is formed through the side column. Compared with the prior art, the integrated magnetic component can meet the requirements of various applications by changing the winding method of the plurality of secondary windings.

Description

TECHNICAL FIELD

[0001] The present application relates to magnetic elements, in particular to transformers, integrated magnetic components composed of inductors and switching power supplies. BACKGROUND

[0002] With the rapid development of switching power supply technology, power supply products gradually develop towards high efficiency, small size, high frequency and flatness. In the design of switching power supply, the most important two types of devices are power semiconductor devices and magnetic elements. With the birth of the third generation of power semiconductor devices represented by GaN and SiC, the loss of switching devices has been significantly reduced, and switching power supply has thus possessed the space for further improving power density.

[0003] However, the magnetic elements of the current product end mainly adopt discrete transformer and inductor devices. Among them, the discrete transformer magnetic component is the traditional winding method of winding the primary and secondary sides on the middle column, which will bring problems such as many turns, high loss and high copper cost in high turn ratio low voltage and large current application occasions. At the same time, the use of discrete inductor magnetic components will further increase the board space and loss of the product. Magnetic elements account for about 15%-20% of the board space of the entire power supply product, and occupy a relatively large proportion in switching power supply. Therefore, if integrated magnetic components are used, the transformer and inductor magnetic components or multiple transformer magnetic components can be integrated into one, which can effectively reduce the size and loss of multiple discrete magnetic components, and bring qualitative improvement to the performance of power supply products.

[0004] At present, the conventional magnetic integration schemes mainly include primary and secondary winding separation, matrix magnetic and decoupling magnetic integration. The primary and secondary winding separation magnetic integration can realize the magnetic integration of inductors and transformers by using leakage inductance, but the integrated inductance is limited. The matrix magnetic and decoupling magnetic integration can realize the magnetic integration of inductors and transformers or multiple transformers and multiple inductors, and at the same time can effectively reduce the height of the magnetic component, but cannot realize the reuse of transformer columns and inductor columns. Moreover, the above two types of conventional magnetic integration schemes cannot effectively reduce the number of turns of the winding, limiting their applicability in high turn ratio applications.

[0005] Therefore, an innovative integrated magnetic component scheme is needed, which can realize the reuse integration of transformers and inductors and reduce the number of turns of the transformer, to further improve the performance of power supply products. SUMMARY

[0006] The present application aims at the deficiencies of the prior art, and discloses a new integrated technology, which is different from the conventional primary and secondary winding separation, matrix magnet and decoupling magnet integration, and creatively integrates transformer column and inductor column reuse magnet and fractional turn technology, so as to improve the technical problems of large board space, many turns, high loss and high copper cost caused by the discrete or conventional integrated magnetic components. Through the transformer and inductor integration or multiple transformer magnet integration and fractional turn technology, the board space, turns, loss and cost of the magnetic component can be effectively reduced, and the overall performance of the product is improved.

[0007] To achieve the above-mentioned application purposes, the present application provides the following technical solutions:

[0008] An integrated magnetic component includes a magnetic core and a PCB winding, the PCB winding includes a primary winding and a plurality of secondary windings, the magnetic core includes a magnetic column, a top cover and a bottom cover, the magnetic column of the magnetic core includes a middle column and side columns arranged on both sides of the middle column; the primary winding is wound on the middle column; the secondary windings are wound outside the middle column and one side column and do not pass between the middle column and the side column, so as to form fractional turn winding through the side column.

[0009] Preferably, the secondary windings include a first secondary winding and a second secondary winding, and the side columns include a first side column and a second side column; the first secondary winding is wound outside the first side column and the middle column and does not pass between the first side column and the middle column; and the second secondary winding is wound outside the second side column and the middle column and does not pass between the second side column and the middle column.

[0010] Preferably, the secondary windings include a first secondary winding and a second secondary winding, and the side columns include a first side column and a second side column; the first secondary winding is wound on the first side column; and the second secondary winding is wound outside the first side column and the middle column and does not pass between the first side column and the middle column, so as to form a partial winding shared by the first secondary winding and the second secondary winding; or the first secondary winding is wound on the second side column, and the second secondary winding is wound outside the second side column and the middle column and does not pass between the second side column and the middle column, so as to form a partial winding shared by the first secondary winding and the second secondary winding.

[0011] Preferably, the magnetic column can be opened to form an air gap, so as to be applied to different circuit topologies.

[0012] The present application also provides a switching power supply including the above-mentioned integrated magnetic component, the secondary windings include two, the two secondary windings and the primary winding share the magnetic core of the integrated magnetic component, and the working conditions of the two secondary windings and the magnetic core are that, in a half cycle, one secondary winding and the magnetic core form a transformer with a secondary fractional turn, and one secondary winding and the magnetic core form an inductor; and the working conditions of the secondary windings are switched once every half cycle, so as to ensure that a transformer with a secondary fractional turn and an inductor in a secondary circuit are stably formed in one cycle, and the winding wire ends of the two secondary windings are independently led out to be connected to the circuit topology, so as to realize full-wave rectification.

[0013] Preferably, the two secondary windings are a first secondary winding and a second secondary winding, and the circuit connection relationship of the full-wave rectification secondary circuit is that one end of the first secondary winding is connected to one end of a capacitor Co through a first diode D1, one end of the second secondary winding is connected to one end of the capacitor Co through a second diode D2, the other end of the capacitor Co is connected to the other end of the first secondary winding and the other end of the second secondary winding, and the capacitor Co is used to be connected in parallel across an output load Ro.

[0014] The application further provides a switching power supply comprising the integrated magnetic component, wherein the secondary windings comprise four, the four secondary windings and the primary winding share a magnetic core of the integrated magnetic component, two transformers with secondary winding fractional turns are formed, and the full-wave rectification is realized by connecting the four secondary windings to a circuit topology in a separate winding wire end independent leading mode.

[0015] Preferably, the four secondary windings are a first secondary winding, a second secondary winding, a third secondary winding and a fourth secondary winding, the first and third secondary windings are wound outside the first side column and the middle column and do not pass through between the first side column and the middle column, and the second and fourth secondary windings are wound outside the second side column and the middle column and do not pass through between the second side column and the middle column; the circuit connection relationship of the integrated magnetic component full-wave rectification secondary circuit is that one end of the first and second secondary windings is connected to one end of a capacitor Co through a first diode D1, the other end of the first and second secondary windings is connected to the other end of the capacitor Co; one end of the third and fourth secondary windings is connected to one end of the capacitor Co through a second diode D2, the other end of the third and fourth secondary windings is connected to the other end of the capacitor Co; the capacitor Co is used to be connected in parallel across an output load Ro; when the integrated magnetic component works in a positive half cycle, the first and second secondary windings work simultaneously, which is equivalent to two transformers in parallel; when the integrated magnetic component works in a negative half cycle, the third and fourth secondary windings work simultaneously, which is equivalent to two transformers in parallel.

[0016] The application further provides a switching power supply comprising the integrated magnetic component, wherein the secondary windings comprise two, the two secondary windings and the primary winding share a magnetic core of the integrated magnetic component to form a transformer with secondary winding fractional turns, and the full-bridge rectification is realized by connecting the two secondary windings to a circuit topology in a parallel connection leading mode.

[0017] Preferably, the two secondary windings are a first secondary winding and a second secondary winding, and the circuit connection relationship of the full-bridge rectification is that one end of the first secondary winding and one end of the second secondary winding are connected to the anode of the third diode D3 and the cathode of the fourth diode D4 respectively, the other end of the first secondary winding and the other end of the second secondary winding are connected to the anode of the first diode D1 and the cathode of the second diode D2 respectively, the cathode of the first diode D1 and the cathode of the third diode D3 are connected to one end of the capacitor Co, the anode of the second diode D2 and the anode of the fourth diode D4 are connected to the other end of the capacitor Co, and the capacitor Co is used in parallel across the output load Ro.

[0018] Preferably, the above-mentioned switching power supply adopts a frequency modulation control mode with a 50% duty cycle.

[0019] The application mainly starts from the two aspects of magnetic circuit integration multiplexing and fractional turn technology, discloses an integrated magnetic component design scheme in line with the development of future power supply products, and has the following beneficial effects compared with the prior art:

[0020] 1. Through the magnetic integration technology, the magnetic integration of one transformer column and one inductor column or the magnetic integration of two transformers is realized; compared with discrete magnetic components, the volume and loss of the magnetic components are effectively reduced;

[0021] 2. Through the fractional turn technology, the number of turns of the primary winding is effectively reduced, and the height of the magnetic core window, the loss and cost of the copper winding are reduced. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1a It is a three-dimensional structure diagram of the integrated magnetic component of the first embodiment of the application;

[0023] Figure 1b It is a winding top view structure diagram of the magnetic column of the integrated magnetic component of the first embodiment of the application;

[0024] Figure 2 It is a secondary side circuit principle diagram of the integrated magnetic component of the first embodiment of the application applied in full-wave rectification;

[0025] Figure 3 It is a secondary side circuit principle diagram of the integrated magnetic component of the first embodiment of the application applied in full-bridge rectification;

[0026] Figure 4 It is a full-wave rectification fractional turn resonance topology of the integrated magnetic component of the first embodiment of the application

[0027] Figure 5 It is a main working output waveform of the full-wave rectification fractional turn resonance topology of the integrated magnetic component of the first embodiment of the application;

[0028] Figure 6aA schematic view of a top view structure and a secondary side circuit of a magnetic column winding of an integrated magnetic component according to a second embodiment of the present application;

[0029] Figure 6b A schematic view of a top view structure and a secondary side circuit of another magnetic column winding of an integrated magnetic component according to a second embodiment of the present application;

[0030] Figure 7 A schematic view of a top view structure and a secondary side circuit of a magnetic column winding of an integrated magnetic component according to a third embodiment of the present application.

[0031] In the above figures, the reference signs are explained as follows:

[0032] 101 first side column, 103 second side column, 102 middle column, 104 primary winding, 105 first secondary winding, 106 second secondary winding, 107 bottom cover, 108 top cover

[0033] 201 first side column, 203 second side column, 202 middle column, 204 primary winding, 205 first secondary winding, 206 second secondary winding, 207 common connection point

[0034] 301 first side column, 303 second side column, 302 middle column, 304 primary winding, 305 first secondary winding, 306 second secondary winding, 307 third secondary winding, 308 fourth secondary winding

[0035] Vin power input terminal, Cin input terminal capacitor, Cr resonance capacitor, P1 upper switch, P2 lower switch, D1 first diode, D2 second diode, D3 third diode, D4 fourth diode, Co capacitor, Ro output load, wherein the diodes have solid and hollow symbols, respectively representing the on / off states in the working period. DETAILED DESCRIPTION

[0036] The technical solutions of the present application are described below in conjunction with the drawings and embodiments, so that those skilled in the art can better understand the present application. However, the specific implementation of the technical solutions of the present application is not limited thereto.

[0037] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0038] Unless otherwise specified, all technical and scientific terms used in the present application have the same meaning as generally understood by those skilled in the art to which the present application belongs.

[0039] In the present application, the orientation words such as "upper, lower, left, right" and the like used without the opposite description are generally directed to the directions shown in the drawings or the directions of the components themselves in the vertical, perpendicular or gravity direction; similarly, for the convenience of understanding and description, "inner, outer" refers to the inner and outer relative to the contour of the components themselves, but the above orientation words are not used to limit the present application.

[0040] Please refer to Figures 1a to 7 The present application mainly starts from the two aspects of magnetic circuit integration multiplexing and fractional turn technology, and innovatively improves an integrated magnetic component, which comprises a magnetic core and a PCB winding, the PCB winding comprises a primary winding and a plurality of secondary windings, the magnetic core comprises a magnetic column, a top cover and a bottom cover, the magnetic column of the magnetic core comprises a middle column and side columns arranged on both sides of the middle column, the primary winding is wound on the middle column, and the secondary windings are wound outside the middle column and one side column without passing through the middle column and the side column, so as to form fractional turn winding through the side column.

[0041] Preferably, the secondary windings comprise a first secondary winding 105 and a second secondary winding 106, the side columns comprise a first side column 101 and a second side column 103, the first secondary winding 105 is wound outside the first side column 101 and the middle column 102 without passing through the first side column 101 and the middle column 102, and the second secondary winding 106 is wound outside the second side column 103 and the middle column 102 without passing through the second side column 103 and the middle column 102. In other embodiments, the secondary windings can also be improved to comprise a first secondary winding and a second secondary winding, the side columns comprise a first side column and a second side column, the first secondary winding is wound outside the first side column and the middle column without passing through the first side column and the middle column, and the second secondary winding is wound on the first side column. An air gap can also be arranged on the middle column for application to different circuit topologies.

[0042] The integrated magnetic component of the present application is applied to a switching power supply, and a switching power supply comprising the integrated magnetic component of the present application is obtained, wherein the secondary windings comprise two, and the two secondary windings and the primary winding share the magnetic core of the integrated magnetic component, and the working conditions of the two secondary windings and the magnetic core are that, in a half cycle, one secondary winding and the magnetic core form a transformer with a secondary fractional turn, and one secondary winding and the magnetic core form an inductor; and the working conditions of the secondary windings are switched once every half cycle, so as to ensure that a transformer with a secondary fractional turn and an inductor are stably formed in a secondary circuit in a period, and the full-wave rectification is realized by connecting the winding wire ends of the two secondary windings to the circuit topologies in a separate manner. Figure 2As shown, the two secondary windings are respectively the first secondary winding 105 and the second secondary winding 106, and the circuit connection relationship of the full-wave rectification secondary circuit is that one end of the first secondary winding 105 is connected to one end of the capacitor C through the diode D1, one end of the second secondary winding 106 is connected to one end of the capacitor C through the diode D2, the other end of the capacitor C is connected to the other end of the first secondary winding and the other end of the second secondary winding, and the capacitor C is used to be connected in parallel across the output load Ro.

[0043] The integrated magnetic component stack of the present application is applied to a switching power supply, and a switching power supply including the integrated magnetic component of the present application is obtained, wherein the secondary windings include four, the four secondary windings and the primary winding share a magnetic core of the integrated magnetic component, form two transformers with secondary winding fractional turns, and are connected to the circuit topology through the independent winding wire end leading-out mode of the four secondary windings to realize two-stage parallel full-wave rectification. Figure 7 As shown, the four secondary windings are respectively the first secondary winding 305, the second secondary winding 306, the third secondary winding 307 and the fourth secondary winding 308, the first transformer works in the positive half cycle, and the circuit connection relationship of the full-wave rectification is that one end of the first secondary winding 305 is connected to one end of the capacitor C through the diode D1, one end of the second secondary winding 306 is connected to one end of the capacitor C through the diode D2, the other end of the capacitor C is connected to the other end of the first secondary winding and the other end of the second secondary winding; the second transformer works in the negative half cycle, and the circuit connection relationship of the full-wave rectification is that one end of the third secondary winding 307 is connected to one end of the capacitor C through the diode D1, one end of the fourth secondary winding 308 is connected to one end of the capacitor C through the diode D2, the other end of the capacitor C is connected to the other end of the third secondary winding and the other end of the fourth secondary winding, and the capacitor C is used to be connected in parallel across the output load Ro.

[0044] The integrated magnetic component of the present application is applied to a switching power supply, and a switching power supply including the integrated magnetic component of the present application is obtained, wherein the secondary windings include two, the two secondary windings and the primary winding share a magnetic core of the integrated magnetic component to form a transformer with secondary winding fractional turns, and are connected to the circuit topology through the parallel connection leading-out mode of the winding wire ends of the two secondary windings to realize full-bridge rectification. Figure 3 As shown, the two secondary windings are respectively the first secondary winding 105 and the second secondary winding 106, and the circuit connection relationship of the full-wave rectification secondary circuit is that one end of the first secondary winding 105 is connected to one end of the capacitor C through the diode D1, one end of the second secondary winding 106 is connected to one end of the capacitor C through the diode D2, the other end of the capacitor C is connected to the other end of the first secondary winding and the other end of the second secondary winding, and the capacitor C is used to be connected in parallel across the output load Ro.

[0045] The integrated magnetic component of the present application can realize the application requirements of magnetic components of various circuits by changing the winding method of the plurality of secondary winding. The turns of the primary winding and the secondary winding are reduced by dividing the magnetic flux of the primary winding by 1 / 2 and realizing fractional turns of the secondary winding, thereby reducing the height, copper loss and cost. The inductor column and the transformer column can be shared by changing the winding method of the secondary winding, thereby realizing the coupling magnetic integration of the inductor and the transformer. The two transformers can be magnetically integrated in parallel by changing the winding method of the secondary winding. Thus, the application range of the three magnetic column transformer is widened by magnetic integration, and the volume and loss of the magnetic component can be significantly reduced compared with discrete devices.

[0046] First embodiment

[0047] The first embodiment provides a fractional turn integrated magnetic component and a switching power supply. Figure 1a The three-dimensional structure diagram of the integrated magnetic component provided by the first embodiment includes a middle column 102 of a magnetic core, a first side column 101, a second side column 103, a top cover 108 and a bottom cover 107. The winding includes a primary winding 104, a first secondary winding 105 and a second secondary winding 106.

[0048] As shown in the figure, Figure 1b The magnetic column winding structure diagram of the integrated magnetic component of the first embodiment is shown. The primary winding 104 is wound on the middle column 102 of the magnetic core. The first secondary winding 105 is wound outside the first side column 101 of the magnetic core and the middle column 102 of the magnetic core without passing through the first side column 101 of the magnetic core and the middle column 102 of the magnetic core. The second secondary winding 106 is wound outside the second side column 103 of the magnetic core and the middle column 102 of the magnetic core without passing through the second side column 103 of the magnetic core and the middle column 102 of the magnetic core. Through the above winding method, the alternating magnetic flux flowing through the primary winding 104 is twice the alternating magnetic flux flowing through the first secondary winding 105 and the second secondary winding 106, thereby realizing the effect of reducing the turns of the primary winding by half compared with the turns of the primary winding of the integer turn magnetic component, and forming a new fractional turn integrated magnetic component structure.

[0049] As shown in the figure, Figure 2 As shown in the figure, if the first secondary winding 105 and the second secondary winding 106 are independently led out, full-wave rectification can be used. One end of the first secondary winding 105 is connected to one end of a capacitor Co through a diode D1. One end of the second secondary winding 106 is connected to one end of the capacitor Co through a diode D2. The other end of the capacitor Co is connected to the other end of the first secondary winding 105 and the other end of the secondary winding 106. The capacitor Co is connected in parallel across the output load Ro. The first side column 101 of the magnetic core and the second side column 102 of the magnetic core realize the multiplexing of one transformer column and one inductor column, that is, the magnetic integration of one transformer and one inductor.

[0050] As shown in the figure, Figure 3As shown, if the two auxiliary windings 105 and 106 are connected in parallel, full-bridge rectification can be used, one end of the first auxiliary winding 105 and one end of the second auxiliary winding 106 are connected to the anode of the third diode D3 and the cathode of the fourth diode D4 respectively, the other end of the first auxiliary winding 105 and the other end of the second auxiliary winding 106 are connected to the anode of the first diode D1 and the cathode of the second diode D2 respectively, the cathode of the first diode D1 and the cathode of the third diode D3 are connected to one end of the capacitor Co, the anode of the second diode D2 and the anode of the fourth diode D4 are connected to the other end of the capacitor Co, and the capacitor Co is connected in parallel across the output load Ro. The two transformers are magnetically integrated through the first side leg 101 and the second side leg 102.

[0051] The first side leg 101, the middle leg 102 and the second side leg 103 of the integrated magnetic core can have the same air gap, or the middle leg 102 can have an air gap while the first side leg 101 and the second side leg 103 have the same other air gap, or the middle leg 102 can have no air gap while the first side leg 101 and the second side leg 103 have the same other air gap, or the middle leg 102 can have an air gap while the first side leg 101 and the second side leg 103 have no air gap.

[0052] The integrated magnetic core can adopt a full-wave or full-bridge rectification structure and be suitable for various topological applications, such as a resonant circuit, a hard full-bridge topology, etc.

[0053] Here, a full-wave rectification fractional-turn resonant circuit topology is taken as an example to introduce the application scenario of the integrated magnetic core of embodiment one. As shown in Figure 4 As shown, the primary winding 104 and the resonant capacitor Cr are connected in series to the primary half-bridge inverter circuit A1, the first auxiliary winding 105 and the second auxiliary winding 106 are connected to the full-wave rectification circuit B1 composed of the first auxiliary rectification diode D1 and the second auxiliary rectification diode D2, and the full-wave rectification circuit B1 is connected to the output load Ro; through the half-cycle alternation of the first auxiliary rectification diode D1 and the second auxiliary rectification diode D2, the first side leg 101 and the second side leg 102 of the magnetic core realize the magnetic column multiplexing function in which one half of the cycle is used as a transformer column and the other half of the cycle is used as an inductor column in one working cycle.

[0054] The frequency modulation control with a 50% duty cycle is used to control the resonant topology, and by reasonably setting the inductance parameters of the integrated magnetic core and other power stage parameters of the full-wave rectification resonant topology, the circuit can work normally, and the working waveform is as shown in Figure 5As shown; where 501 is the driving waveform of switch P1 on the primary side half-bridge inverter circuit, 502 is the driving waveform of switch P2 on the secondary side half-bridge inverter circuit, 503 is the current waveform of primary winding 103, 504 is the current waveform of the first secondary winding 105, 505 is the current waveform of the second secondary winding 106, and 506 is the output voltage waveform of the topology. Time / mSecs represents... Figure 5 The time axis on the horizontal axis is in milliseconds, and 10uSecs / div means that one cell represents 10 microseconds.

[0055] like Figure 4 and Figure 5 As shown, when the first secondary winding 105 is turned on and outputs current, the first side post 101 of the magnetic core acts as a transformer post, and the second side post 103 of the magnetic core acts as an inductor post; when the second secondary winding 106 is turned on and outputs current, the second side post 103 of the magnetic core acts as a transformer post, and the first side post 101 of the magnetic core acts as an inductor post; therefore, the first side post 101 and the second side post 103 of the magnetic core achieve the magnetic post multiplexing function of acting as a transformer post for half a cycle and an inductor post for the other half cycle within one working cycle.

[0056] Second Embodiment

[0057] Example 2 provides a fractional-turn integrated magnetic component, which includes: a magnetic core containing three magnetic pillars, a top cover and a bottom cover, and a winding including two primary windings and two secondary windings;

[0058] like Figure 6a This is a top view of the magnetic column winding structure of the integrated magnetic component in the second embodiment. The primary winding 204 is wound on the magnetic core column 202. By sharing a portion of the winding between the first secondary winding 105 and the second secondary winding 106 in the first embodiment of the present invention, a three-port secondary winding structure can be realized.

[0059] like Figure 6a As shown, the secondary winding of the three-port terminal is a fractional-turn secondary winding structure, which can be composed of two parts; the first secondary winding 205 only passes through the slot between the core center post 202 and the core second side post 203, forming a half-turn fractional-turn structure; the second secondary winding 206 is wound around the core second side post 203 and the core center post 202 and does not pass between the core second side post 203 and the core center post 202; the connection point of the first secondary winding 205 and the second secondary winding 206 is 207, so as to share part of the winding of the second secondary winding 206.

[0060] like Figure 6bAs shown, another type of magnetic post winding structure is used. The secondary winding of the three ports is a fractional-turn secondary winding structure, which can be composed of two parts. The second secondary winding 206 is wound outside the first side post 201 and the middle post 202 of the magnetic core and does not pass between the first side post 201 and the middle post 202 of the magnetic core. The first secondary winding 205 only passes through the slot between the middle post 202 and the first side post 201 of the magnetic core, forming a half-turn fractional-turn structure. The connection point of the first secondary winding 205 and the second secondary winding 206 is 207, so that they share part of the winding of the second secondary winding 206.

[0061] Therefore, by utilizing the fractional-turn secondary winding technology and by sharing part of the winding between the second secondary winding 206 and the first secondary winding 205, a three-port fractional-turn secondary winding structure can be realized. This structure can effectively reduce the winding length and the number of winding layers, but the secondary winding is also limited to one turn.

[0062] By using the above-mentioned winding method for primary and secondary windings, the AC magnetic flux flowing through the primary winding 204 can be twice that flowing through the first secondary winding 205 and the second secondary winding 206, thereby achieving the effect of reducing the number of turns of the primary winding by half compared to the number of turns of the primary winding of an integer-turn magnetic component.

[0063] Example 2: A new fractional-turn integrated magnetic component structure is formed by using fractional-turn technology for primary and secondary windings.

[0064] like Figure 6a As shown, the three-port secondary winding structure, consisting of a first secondary winding 205 and a second secondary winding 206, can employ full-wave rectification. One end of the first secondary winding 205 is connected to one end of capacitor Co via diode D2, and one end of the second secondary winding 206 is connected to one end of capacitor Co via diode D1. The other end of the first secondary winding 205 is connected to the second secondary winding 206, and the other end of capacitor Co is connected to the other end of the second secondary winding 206. Capacitor Co is used to connect in parallel across the output load Ro, thereby realizing the multiplexing of a transformer post and an inductor post, that is, realizing the magnetic integration of a transformer and an inductor.

[0065] like Figure 6b As shown, the three-port secondary winding structure consisting of secondary winding 205 and secondary winding 206 can be used for full-wave rectification. One end of the second secondary winding 206 is connected to one end of capacitor Co via diode D2, and one end of the first secondary winding 205 is connected to one end of capacitor Co via diode D1. The other end of the first secondary winding 205 is connected to the second secondary winding 206, and the other end of capacitor Co is connected to the other end of the second secondary winding 206. Capacitor Co is used to be connected in parallel across the output load Ro, thereby realizing the multiplexing of a transformer column and an inductor column, that is, realizing the magnetic integration of a transformer and an inductor.

[0066] The integrated magnetic core first side post 201, magnetic core middle post 202, and magnetic core second side post 203 can have the same air gap opened simultaneously; the magnetic core middle post 202 can have one air gap opened, and then the magnetic core first side post 201 and magnetic core second side post 203 can have the same other air gap opened; the magnetic core middle post 202 can have no air gap opened, and then the magnetic core first side post 201 and magnetic core second side post 203 can have the same other air gap opened; or the magnetic core middle post 202 can have one air gap opened, and then the magnetic core first side post 201 and magnetic core second side post 203 can have no air gap opened.

[0067] The integrated magnetic component can adopt a full-wave rectification structure, which is suitable for various topology applications, such as resonant circuits and hard full-bridge topologies.

[0068] Third Embodiment

[0069] Example 3 provides a fractional-turn integrated magnetic component, which includes: a magnetic core containing three magnetic pillars, a top cover and a bottom cover, and a winding including one primary winding and four secondary windings.

[0070] like Figure 7 The diagram shown is a top view of the integrated magnetic component in the third embodiment. The primary winding 304 is wound around the central column 302 of the magnetic core. The secondary winding structure is based on the two secondary windings of the integrated magnetic component in the first embodiment of the present invention, with the addition of two secondary windings: a first secondary winding 305 wound around the first side column 301 and the central column 302 of the magnetic core without passing between them; and a secondary winding 305 wound around the second side column 303 and the central column 302 of the magnetic core without passing between them. Based on the second secondary winding 306 that passes between the side post 303 and the core center post 302, a third secondary winding 307 is added that winds around the outside of the first side post 301 and the core center post 302 and does not pass between them. Then, a fourth secondary winding 308 is added that winds around the outside of the second side post 303 and the core center post 302 and does not pass between them, thus forming an integrated magnetic component structure containing four secondary windings.

[0071] By using the above-mentioned winding method for the primary and secondary windings, the AC magnetic flux flowing through the primary winding 304 can be twice that flowing through the first secondary winding 305, the second secondary winding 306, the third secondary winding 307, and the fourth secondary winding 308. This results in the primary winding turning number being reduced by half compared to the number of turns in an integer-turn magnetic component, thus forming a new fractional-turn integrated magnetic component structure.

[0072] like Figure 7As shown, the integrated magnetic component structure containing four auxiliary winding: by connecting the first auxiliary winding 305, the second auxiliary winding 306 in parallel, the third auxiliary winding 307, the fourth auxiliary winding 308 in parallel, full-wave rectification can be used, the first auxiliary winding 305, the third auxiliary winding 307 are wound on the first limb 301 of the magnetic core and the middle column 302 of the magnetic core and do not pass through the first limb 301 of the magnetic core and the middle column 302 of the magnetic core, the second auxiliary winding 306, the fourth auxiliary winding 308 are wound on the second limb 303 of the magnetic core and the middle column 302 of the magnetic core and do not pass through the second limb 303 of the magnetic core and the middle column 302 of the magnetic core; the circuit connection relationship of the integrated magnetic component auxiliary winding full-wave rectification is that one end of the first auxiliary winding 305 and the second auxiliary winding 306 is connected to one end of the capacitor Co through the diode D1, the other end of the first auxiliary winding 305 and the second auxiliary winding 306 is connected to the other end of the capacitor Co; one end of the third auxiliary winding 307 and the fourth auxiliary winding 308 is connected to one end of the capacitor Co through the diode D2, the other end of the third auxiliary winding 307 and the fourth auxiliary winding 308 is connected to the other end of the capacitor Co; the capacitor Co is used to be connected in parallel across the output load Ro; when the integrated magnetic component works in the positive half cycle, the first auxiliary winding 305 and the second auxiliary winding 306 work at the same time, which is equivalent to two transformers connected in parallel; when the integrated magnetic component works in the negative half cycle, the third auxiliary winding 307 and the fourth auxiliary winding 308 work at the same time, which is equivalent to two transformers connected in parallel, realizing the magnetic integration of two transformers.

[0073] The first limb 301 of the magnetic core, the middle column 302 of the magnetic core, and the second limb 303 of the magnetic core of the integrated magnetic component can have the same air gap; the middle column 302 of the magnetic core can have an air gap, and then the first limb 301 of the magnetic core and the second limb 303 of the magnetic core can have the same other air gap; the middle column 302 of the magnetic core can not have an air gap, and then the first limb 301 of the magnetic core and the second limb 303 of the magnetic core can have the same other air gap; the middle column 302 of the magnetic core can have an air gap, and then the first limb 301 of the magnetic core and the second limb 303 of the magnetic core can not have an air gap.

[0074] The integrated magnetic component can adopt a full-wave rectification structure and be suitable for various topological applications, such as a resonant circuit, a hard full-bridge topology, etc.

[0075] The above-described embodiments are merely examples of the technical solutions and inventive content of the present application. It should be noted that the above-described embodiments should not be regarded as limiting the present application. For those of ordinary skill in the art, several improvements and refinements can be made without departing from the spirit and scope of the present application. Such improvements and refinements should also be regarded as falling within the protection scope of the present application.

Claims

1. An integrated magnetic component comprising a magnetic core and a PCB winding, the PCB winding comprising a primary winding and a plurality of secondary windings, the magnetic core comprising a magnetic leg, a top cover and a bottom cover, characterized in that: the magnetic leg of the magnetic core comprises a middle leg and side legs arranged on both sides of the middle leg; the primary winding is wound on the middle leg, and the secondary windings are wound outside the middle leg and one side leg without passing between the middle leg and the side leg to form fractional-turn winding through the side leg.

2. The integrated magnetic component of claim 1, wherein: the secondary windings comprise a first secondary winding and a second secondary winding, and the side legs comprise a first side leg and a second side leg, the first secondary winding is wound outside the first side leg and the middle leg without passing between the first side leg and the middle leg, and the second secondary winding is wound outside the second side leg and the middle leg without passing between the second side leg and the middle leg.

3. The integrated magnetic component of claim 1, wherein: the secondary windings comprise a first secondary winding and a second secondary winding, and the side legs comprise a first side leg and a second side leg, the first secondary winding is wound on the first side leg, and the second secondary winding is wound outside the first side leg and the middle leg without passing between the first side leg and the middle leg to form a common partial winding of the first secondary winding and the second secondary winding; or the first secondary winding is wound on the second side leg, and the second secondary winding is wound outside the second side leg and the middle leg without passing between the second side leg and the middle leg to form a common partial winding of the first secondary winding and the second secondary winding.

4. The integrated magnetic component according to any one of claims 1 to 3, characterized in that: the magnetic leg is provided with an air gap, which is used for different circuit topologies.

5. A switched mode power supply comprising the integrated magnetic component of any one of claims 1 to 4, characterized in that: the secondary windings comprise two, and the two secondary windings and the primary winding share the magnetic core of the integrated magnetic component, the working conditions of the two secondary windings and the magnetic core are that, in a half cycle, one secondary winding and the magnetic core form a transformer with a secondary fractional turn, and one secondary winding and the magnetic core form an inductor; and the working conditions of the secondary windings are switched once every half cycle to ensure that a transformer with a secondary fractional turn and an inductor are stably formed in one period, and the two secondary windings are independently connected to the circuit topology through the winding wire ends to realize full-wave rectification.

6. The switching power supply of claim 5, wherein: the two secondary windings are a first secondary winding and a second secondary winding, and the connection relationship of the full-wave rectification secondary circuit is that one end of the first secondary winding is connected to one end of a capacitor Co through a first diode D1, one end of the second secondary winding is connected to one end of the capacitor Co through a second diode D2, the other end of the capacitor Co is connected to the other end of the first secondary winding and the other end of the second secondary winding, and the capacitor Co is connected in parallel across an output load Ro.

7. A switched mode power supply comprising the integrated magnetic component of any one of claims 1 to 4, characterized in that: the secondary windings comprise four, and the four secondary windings and the primary winding share a set of magnetic cores of the integrated magnetic component to form two transformers with secondary fractional turns, and the four secondary windings are independently connected to the circuit topology through the winding wire ends to realize full-wave rectification.

8. The switching power supply of claim 7, wherein: The four auxiliary side windings are a first auxiliary side winding, a second auxiliary side winding, a third auxiliary side winding and a fourth auxiliary side winding, the first and third auxiliary side windings are wound outside the first limb and the middle limb and do not pass through between the first limb and the middle limb, the second and fourth auxiliary side windings are wound outside the second limb and the middle limb and do not pass through between the second limb and the middle limb; the circuit connection relationship of the integrated magnetic component auxiliary side full-wave rectification is that one end of the first and second auxiliary side windings is connected to one end of a capacitor Co through a first diode D1, and the other end of the first and second auxiliary side windings is connected to the other end of the capacitor Co; one end of the third and fourth auxiliary side windings is connected to one end of the capacitor Co through a second diode D2, and the other end of the third and fourth auxiliary side windings is connected to the other end of the capacitor Co; the capacitor Co is used in parallel between the output load Ro; when the integrated magnetic component works in a positive half cycle, the first and second auxiliary side windings work simultaneously, which is equivalent to two transformers in parallel; when the integrated magnetic component works in a negative half cycle, the third and fourth auxiliary side windings work simultaneously, which is equivalent to two transformers in parallel.

9. A switched mode power supply comprising the integrated magnetic component of any of claims 1 to 4, characterized in that: The auxiliary side windings include two, the two auxiliary side windings and the primary winding share the magnetic core of the integrated magnetic component to form a transformer with auxiliary side fractional turns, and are connected in parallel through winding wire ends of the two auxiliary side windings to realize full-bridge rectification.

10. The switching power supply of claim 9, wherein: The two auxiliary side windings are a first auxiliary side winding and a second auxiliary side winding, and the circuit connection relationship of the full-bridge rectification is that one end of the first auxiliary side winding and one end of the second auxiliary side winding are respectively connected to an anode of a third diode D3 and a cathode of a fourth diode D4, the other end of the first auxiliary side winding and the other end of the second auxiliary side winding are respectively connected to an anode of a first diode D1 and a cathode of a second diode D2, a cathode of the first diode D1 and a cathode of the third diode D3 are connected to one end of a capacitor Co, an anode of the second diode D2 and an anode of the fourth diode D4 are connected to the other end of the capacitor Co, and the capacitor Co is used in parallel between the output load Ro.

11. Switching power supply according to any of claims 5 to 10, characterized in that: The switching power supply adopts a frequency modulation control mode with a 50% duty cycle.

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