Magnetic integrated forward converter and electronic equipment

Abstract

The utility model relates to a magnetic integrated forward converter and electronic equipment. The forward converter comprises a primary side circuit, a secondary side circuit and an integrated magnetic part. The integrated magnetic part comprises a primary winding, a secondary winding, an output inductor winding and an integrated magnetic core. And the primary winding, the secondary winding and the inductance winding are wound on the integrated magnetic core. The primary side circuit is connected with the primary side winding to form a primary side loop; the secondary circuit is connected with the secondary winding to form an induction loop; and the secondary circuit is connected with the output inductor winding to form an output loop. When the primary side loop is conducted, a first current is generated on the primary side winding; the secondary winding generates a second current based on the first current induction; the second current flows into the output inductance winding through the induction loop and is output through the output loop; and the magnetic flux generated by the second current on the secondary winding and the magnetic flux generated by the second current on the output inductance winding are mutually counteracted. According to the invention, the magnetic core loss of the forward converter after magnetic integration can be reduced, the output current pulsation is reduced, and the overall power density is improved.

Description

Technical Field

[0001] The present application relates to the technical field of electronic circuits, and in particular to a magnetically integrated forward converter and electronic equipment. Background Art

[0002] Among the many DC / DC converter circuit topologies, the forward converter is widely used in small and medium-power conversion applications due to its simple structure, input-output voltage isolation, and reliable operation. Forward converters can be classified in many ways, including winding-reset forward converters, resonant-reset converters, two-switch forward converters, and active-clamp forward converters, based on their magnetic reset method. Compared to two-terminal converters such as full-bridge, half-bridge, and push-pull converters, the output filter of a forward converter operates at a lower frequency, resulting in greater output current pulsation. Furthermore, to ensure the transformer completes magnetic reset or reduce the voltage stress on the main switch, the maximum duty cycle of the forward converter is generally limited, which also leads to greater output current pulsation.

[0003] In order to reduce output pulsation, the traditional method is to increase the filter inductor or filter capacitor, which limits the further improvement of power density and also affects the dynamic performance of the converter. Utility Model Content

[0004] Based on this, it is necessary to provide a magnetically integrated forward converter and an electronic device that can reduce the current ripple of the forward converter and improve the power density of the converter.

[0005] In a first aspect, a magnetic integrated forward converter is provided, comprising a primary circuit, a secondary circuit, and an integrated magnetic component; the integrated magnetic component comprises a primary winding, a secondary winding, an output inductor winding, and an integrated magnetic core; the primary winding, the secondary winding, and the inductor winding are all wound on the integrated magnetic core;

[0006] The primary circuit is connected to the primary winding to form a primary loop; the secondary circuit is connected to the secondary winding to form an inductive loop; the secondary circuit is connected to the output inductive winding to form an output loop;

[0007] When the primary circuit is turned on, a first current is generated on the primary winding; the secondary winding generates a second current based on the induction of the first current; the second current flows into the output inductor winding through the induction circuit and is output through the output circuit; wherein the secondary magnetic flux generated by the second current on the secondary winding and the inductor magnetic flux generated by the second current on the output inductor winding cancel each other out.

[0008] In one embodiment, the positive input terminal of the primary circuit is connected to one end of the primary winding, and the negative input terminal of the primary circuit is connected to the other end of the primary winding.

[0009] In one embodiment, the positive output end of the secondary circuit is connected to one end of the output inductor winding, the negative output end of the secondary circuit is connected to one end of the secondary winding, and the other end of the output inductor winding is connected to the other end of the secondary winding.

[0010] In one embodiment, the integrated magnetic core includes a first E-shaped magnetic core, a second E-shaped magnetic core, and a third E-shaped magnetic core having the same structure and size;

[0011] The first E-shaped magnetic core and the second E-shaped magnetic core are placed opposite to each other, and the third E-shaped magnetic core and the second E-shaped magnetic core are placed in the same direction;

[0012] The primary winding is wound on the first E-shaped magnetic core, the secondary winding is wound on the second E-shaped magnetic core, and the output inductor winding is wound on the third E-shaped magnetic core.

[0013] In one embodiment, each E-shaped magnetic core includes a magnetic rod and three magnetic columns, wherein the magnetic columns are vertically arranged on the magnetic rod.

[0014] The first magnetic column, the second magnetic column, and the third magnetic column of the first E-shaped magnetic core are respectively connected to the fourth magnetic column, the fifth magnetic column, and the sixth magnetic column of the second E-shaped magnetic core in pairs; the primary winding is wound on the second magnetic column, and the secondary winding is wound on the fifth magnetic column;

[0015] The seventh magnetic column, the eighth magnetic column, and the ninth magnetic column of the third E-shaped magnetic core are connected to the magnetic rod of the second E-shaped magnetic core; and the output inductor winding is wound around the eighth magnetic column.

[0016] In one embodiment, the second magnetic column is located between the first magnetic column and the third magnetic column; the fifth magnetic column is located between the fourth magnetic column and the sixth magnetic column; and the eighth magnetic column is located between the seventh magnetic column and the ninth magnetic column.

[0017] In one embodiment, the primary circuit includes an input capacitor C in And the main power tube Q1,

[0018] The input capacitor C in One end of the primary winding is connected to one end of the primary winding, the collector of the main power tube Q1 is connected to the other end of the primary winding, and the emitter of the main power tube Q1 is connected to the input capacitor C in the other end.

[0019] In one embodiment, the secondary circuit includes a freewheeling diode D1 and a freewheeling diode D2.

[0020] The cathode of the freewheeling diode D1 is connected to one end of the secondary winding, the anode of the freewheeling diode D1 is connected to the anode of the freewheeling diode D2, the cathode of the freewheeling diode D2 is connected to the other end of the secondary winding, and the anode of the freewheeling diode D2 is connected to the common ground.

[0021] In one embodiment, the secondary circuit further includes an output capacitor C0 and a load resistor R L ,

[0022] The load resistor R L One end is connected to the positive output end of the secondary circuit, and the load resistor R L The other end of is connected to the negative output end of the secondary circuit; one end of the output capacitor C0 is connected to the positive output end of the secondary circuit, and the other end of the output capacitor C0 is connected to the positive electrode of the freewheeling diode D2.

[0023] In a second aspect, an electronic device is provided, comprising the magnetically integrated forward converter as described in the first aspect.

[0024] The magnetic integrated forward converter and electronic device have the following beneficial effects:

[0025] (1) By designing integrated magnetic components, the transformer and output inductor of the forward converter are magnetically integrated, effectively solving the problems of large filter inductor volume and large output current pulsation in traditional forward converters.

[0026] (2) By utilizing the winding relationship between the positive and secondary windings of the transformer and the output inductor winding and the magnetic core on the integrated magnetic component, the magnetic flux generated by the secondary circuit of the transformer and the output circuit of the output inductor are offset against each other, which is beneficial to reducing the core loss, volume and weight of the forward converter after magnetic integration, reducing the output current pulsation and improving the power density of the whole machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the conventional technology, the following briefly introduces the drawings required for use in the embodiments or the conventional technology descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 is a structural block diagram of a magnetic integrated forward converter in one embodiment;

[0029] Figure 2 is a circuit structure diagram of a magnetic integrated forward converter in one embodiment;

[0030] Figure 3Schematic diagram of magnetic flux distribution on the integrated magnetic component when the main power tube is turned on in one embodiment.

[0031] Explanation of reference numerals: 10 primary circuit; 20 secondary circuit; 30 integrated magnetic component; 301 primary winding; 302 secondary winding; 303 output inductor winding; 304 integrated magnetic core. DETAILED DESCRIPTION

[0032] To facilitate understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings. The accompanying drawings provide embodiments of the present application. However, the present application may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0034] It will be understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor without departing from the scope of this application. The first resistor and the second resistor are both resistors, but they are not the same resistor.

[0035] It can be understood that the “connection” in the following embodiments should be understood as “electrical connection”, “communication connection”, etc. if there is transmission of electrical signals or data between the connected circuits, modules, units, etc.

[0036] It is understood that “at least one” refers to one or more, “a plurality” refers to two or more, and “at least a portion of an element” refers to a portion or all of an element.

[0037] As used herein, the singular forms "a," "an," and "the" may also include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include," "comprising," "having," and the like specify the presence of stated features, integers, steps, operations, components, parts, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof. Furthermore, the term "and / or" as used in this specification includes any and all combinations of the relevant listed items.

[0038] like Figure 1As shown, a magnetic integrated forward converter is provided, comprising a primary circuit 10, a secondary circuit 20, and an integrated magnetic component 30. The integrated magnetic component 30 comprises a primary winding 301, a secondary winding 302, an output inductor winding 303, and an integrated magnetic core 304. The primary winding 301, the secondary winding 302, and the inductor winding 303 are all wound on the integrated magnetic core 304.

[0039] The primary winding 301 and the secondary winding 302 constitute the transformer of the original forward converter, and the output inductor winding 303 constitutes the filter output inductor of the original forward converter.

[0040] The primary circuit 10 is connected to the primary winding 301 to form a primary loop. The secondary circuit 20 is connected to the secondary winding 302 to form an inductive loop. The secondary circuit 20 is connected to the output inductive winding 303 to form an output loop.

[0041] When the primary circuit 10 is conducting, a first current is generated in the primary winding 301. The secondary winding 302 generates a second current based on the first current. The second current flows through the induction circuit into the output inductor winding 303 and is output through the output circuit. The secondary magnetic flux generated by the second current in the secondary winding 302 and the inductor magnetic flux generated by the second current in the output inductor winding 303 cancel each other out.

[0042] In this embodiment, the transformer and output inductor of the forward converter are magnetically integrated by designing an integrated magnetic component, which effectively solves the problems of large filter inductor size and large output current pulsation in traditional forward converters. At the same time, by utilizing the winding relationship between the positive and secondary windings of the transformer and the output inductor winding and the magnetic core on the integrated magnetic component, the magnetic flux generated by the secondary loop of the transformer and the output loop of the output inductor are offset from each other, which is beneficial to reducing the core loss, volume and weight of the forward converter after magnetic integration, reducing output current pulsation, and improving the power density of the whole machine.

[0043] like Figure 2 As shown, a circuit structure diagram of a magnetic integrated forward converter is provided.

[0044] In one embodiment, Figure 2 As shown, the positive input terminal of the primary circuit 10 is connected to one end of the primary winding, and the negative input terminal of the primary circuit 10 is connected to the other end of the primary winding 301 .

[0045] The positive output end of the secondary circuit 20 is connected to one end of the output inductor winding 303 , the negative output end of the secondary circuit 20 is connected to one end of the secondary winding 302 , and the other end of the output inductor winding 303 is connected to the other end of the secondary winding 302 .

[0046] In one embodiment, the integrated magnetic core 30 includes a first E-shaped magnetic core, a second E-shaped magnetic core, and a third E-shaped magnetic core having the same structure and size.

[0047] The first E-type magnetic core is placed opposite to the second E-type magnetic core, and the third E-type magnetic core is placed in the same direction as the second E-type magnetic core; the primary winding is wound on the first E-type magnetic core, the secondary winding is wound on the second E-type magnetic core, and the output inductor winding is wound on the third E-type magnetic core.

[0048] Specifically, each E-shaped magnetic core includes a magnetic rod and three magnetic columns, the magnetic columns being arranged perpendicularly to the magnetic rod. The first, second, and third magnetic columns of the first E-shaped magnetic core are respectively connected in pairs to the fourth, fifth, and sixth magnetic columns of the second E-shaped magnetic core; the primary winding is wound around the second magnetic column, and the secondary winding is wound around the fifth magnetic column. The seventh, eighth, and ninth magnetic columns of the third E-shaped magnetic core are connected to the magnetic rod of the second E-shaped magnetic core; the output inductor winding is wound around the eighth magnetic column.

[0049] The second magnetic column is located between the first magnetic column and the third magnetic column; the fifth magnetic column is located between the fourth magnetic column and the sixth magnetic column; and the eighth magnetic column is located between the seventh magnetic column and the ninth magnetic column.

[0050] In this embodiment, by utilizing the characteristic that the voltage across the forward converter transformer is in the same direction as the voltage across the filter inductor, the primary winding and the secondary winding are wound on the middle magnetic poles of two oppositely placed and connected E-type magnetic cores to realize a magnetically integrated transformer, and the output inductor winding is wound on the middle magnetic pole of the E-type magnetic core placed in the same direction as the second magnetic core to realize a magnetically integrated output inductor, thereby reducing current pulsation and the volume and weight of the magnetic components.

[0051] In one embodiment, Figure 2 As shown, the primary circuit includes an input capacitor C in And the main power tube Q1.

[0052] The input capacitor C in One end of the primary winding is connected to one end of the primary winding, the collector of the main power tube Q1 is connected to the other end of the primary winding, and the emitter of the main power tube Q1 is connected to the input capacitor C in the other end.

[0053] In one embodiment, Figure 2 As shown, the secondary circuit includes a freewheeling diode D1 and a freewheeling diode D2.

[0054] The cathode of the freewheeling diode D1 is connected to one end of the secondary winding, the anode of the freewheeling diode D1 is connected to the anode of the freewheeling diode D2, the cathode of the freewheeling diode D2 is connected to the other end of the secondary winding, and the anode of the freewheeling diode D2 is connected to the common ground.

[0055] In one embodiment, the secondary circuit further includes an output capacitor C0 and a load resistor R L .

[0056] The load resistor R L One end is connected to the positive output end of the secondary circuit, and the load resistor R L The other end of is connected to the negative output end of the secondary circuit; one end of the output capacitor C0 is connected to the positive output end of the secondary circuit, and the other end of the output capacitor C0 is connected to the positive electrode of the freewheeling diode D2.

[0057] In detail, such as Figure 2 As shown, when the main power tube is turned on, the primary circuit generates a first current N P Flows through the primary winding, and the secondary winding is based on the first current N P The second current N is induced S The second current flows through the induction loop and into the output inductor winding. Figure 3 As shown in FIG, the secondary magnetic flux generated by the second current Ns on the secondary winding is directed downward on the magnetic rod of the second E-type magnetic core, and the inductive magnetic flux generated by the second current Ns on the output inductor winding is directed upward on the magnetic rod of the second E-type magnetic core. The two cancel each other out, reducing the iron loss of the magnetic core. When the main power tube is turned off, there is no current in the primary winding on the primary circuit, and the third current Ns on the output inductor winding in the output circuit is L Provided by the voltage U0, the direction is the same as the current direction when the second current Ns flows through the output inductor winding.

[0058] In one embodiment, an electronic device is further provided. The electronic device includes the magnetic integrated forward converter as described in the above embodiments.

[0059] It can be understood that the above-mentioned primary circuit and secondary circuit can also adopt other forms, and are not limited to the forms mentioned in the above embodiments, as long as they can generate a first current on the primary winding so that the magnetic flux of the secondary circuit and the output circuit can offset each other.

[0060] In the description of this specification, reference to the terms "some embodiments" or "other embodiments" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example.

[0061] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0062] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A magnetic integrated forward converter, characterized in that: The device comprises a primary circuit, a secondary circuit and an integrated magnetic component; the integrated magnetic component comprises a primary winding, a secondary winding, an output inductor winding and an integrated magnetic core; the primary winding, the secondary winding and the inductor winding are all wound on the integrated magnetic core; The primary circuit is connected to the primary winding to form a primary loop; the secondary circuit is connected to the secondary winding to form an inductive loop; the secondary circuit is connected to the output inductive winding to form an output loop; When the primary circuit is turned on, a first current is generated on the primary winding; the secondary winding generates a second current based on the induction of the first current; the second current flows into the output inductor winding through the induction circuit and is output through the output circuit; wherein the secondary magnetic flux generated by the second current on the secondary winding and the inductor magnetic flux generated by the second current on the output inductor winding cancel each other out.

2. The magnetic integrated forward converter according to claim 1, characterized in that: The positive input terminal of the primary circuit is connected to one end of the primary winding, and the negative input terminal of the primary circuit is connected to the other end of the primary winding.

3. The magnetic integrated forward converter according to claim 2, characterized in that: The positive output end of the secondary circuit is connected to one end of the output inductor winding, the negative output end of the secondary circuit is connected to one end of the secondary winding, and the other end of the output inductor winding is connected to the other end of the secondary winding.

4. The magnetic integrated forward converter according to claim 1, characterized in that: The integrated magnetic core includes a first E-shaped magnetic core, a second E-shaped magnetic core, and a third E-shaped magnetic core having the same structure and size; The first E-shaped magnetic core and the second E-shaped magnetic core are placed opposite to each other, and the third E-shaped magnetic core and the second E-shaped magnetic core are placed in the same direction; The primary winding is wound on the first E-shaped magnetic core, the secondary winding is wound on the second E-shaped magnetic core, and the output inductor winding is wound on the third E-shaped magnetic core.

5. The magnetic integrated forward converter according to claim 4, characterized in that: Each E-shaped magnetic core includes a magnetic rod and three magnetic columns, wherein the magnetic columns are vertically arranged on the magnetic rod. The first magnetic column, the second magnetic column, and the third magnetic column of the first E-shaped magnetic core are respectively connected to the fourth magnetic column, the fifth magnetic column, and the sixth magnetic column of the second E-shaped magnetic core in pairs; the primary winding is wound on the second magnetic column, and the secondary winding is wound on the fifth magnetic column; The seventh magnetic column, the eighth magnetic column, and the ninth magnetic column of the third E-shaped magnetic core are connected to the magnetic rod of the second E-shaped magnetic core; and the output inductor winding is wound around the eighth magnetic column.

6. The magnetic integrated forward converter according to claim 5, characterized in that: The second magnetic column is located between the first magnetic column and the third magnetic column; the fifth magnetic column is located between the fourth magnetic column and the sixth magnetic column; and the eighth magnetic column is located between the seventh magnetic column and the ninth magnetic column.

7. The magnetic integrated forward converter according to claim 2, characterized in that: The primary circuit includes an input capacitor C in And the main power tube Q1, The input capacitor C in One end of the primary winding is connected to one end of the primary winding, the collector of the main power tube Q1 is connected to the other end of the primary winding, and the emitter of the main power tube Q1 is connected to the input capacitor C in the other end.

8. The magnetic integrated forward converter according to claim 6, characterized in that: The secondary circuit includes a freewheeling diode D1 and a freewheeling diode D2. The cathode of the freewheeling diode D1 is connected to one end of the secondary winding, the anode of the freewheeling diode D1 is connected to the anode of the freewheeling diode D2, the cathode of the freewheeling diode D2 is connected to the other end of the secondary winding, and the anode of the freewheeling diode D2 is connected to the common ground.

9. The magnetic integrated forward converter according to claim 8, characterized in that: The secondary circuit also includes an output capacitor C0 and a load resistor R L , The load resistor R L One end is connected to the positive output end of the secondary circuit, and the load resistor R L The other end of is connected to the negative output end of the secondary circuit; one end of the output capacitor C0 is connected to the positive output end of the secondary circuit, and the other end of the output capacitor C0 is connected to the positive electrode of the freewheeling diode D2.

10. An electronic device, characterized in that: The invention comprises a magnetic integrated forward converter according to any one of claims 1 to 9.

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