DC-DC power supply module

Abstract

The utility model discloses a DC-DC power supply module comprising an input circuit, a transformer assembly and an output circuit which are connected in sequence. The input end of the input circuit is respectively connected with input direct-current power supplies Vi n + and Vi n-; the output end of the output circuit is respectively connected with an output direct-current power supply Vo + and an output direct-current power supply Vo-, the output direct-current power supply Vo + is connected with two output inductors in parallel, the two output inductors are magnetically integrated on an E-shaped magnetic core, and coils of the two output inductors are respectively wound on side columns of the E-shaped magnetic core in the same direction. According to the input circuit and the output circuit, a full bridge is split into two full bridges which are connected in parallel, so that the loss can be effectively reduced, the current output capability can be further improved, and the power density of the module is improved; the transformer adopts two U-shaped magnetic cores, an output inductor is magnetically integrated on one E-shaped magnetic core, and all magnetic elements adopt thin Base, so that the size of the magnetic elements can be effectively reduced by reducing the height of the module, and meanwhile, the thickness of the module is favorably reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of power electronics, in particular to a DC-DC power supply module. Background Art

[0002] With the development of aerospace technology, electric vehicle technology, and industrial automation technology, in order to meet the requirements of various types of electrical equipment for module power supplies and save energy and space, power modules are gradually developing in the direction of high power density, miniaturization, and ultra-thinness. For soft switching circuit topologies such as LLC, the power density of the module can be effectively improved, but for applications with a wide input range, the advantages of traditional hard switching topology circuits are revealed. At the same time, for occasions with large input or output currents, in order to improve efficiency, topological parallel connection is usually adopted, such as staggered BUCK. However, parallel connection will inevitably increase the number of switching devices, magnetic components, etc. For switching devices, the appropriate package size, characteristic parameters, and parallel connection quantity can be selected to control the device loss and device space occupied within a suitable range; for magnetic components, multiple magnetic components can be combined into one by means of magnetic integration, and the space occupied by the entire power supply magnetic components can be reduced by sharing the magnetic circuit.

[0003] At present, for applications with wide input range and high current output, further improvement of module power density is limited by product height, especially for applications with extremely stringent thickness requirements, such as airborne and vehicle-mounted power supplies, which often require the total product thickness to be no more than 8mm or 9mm. For module power supplies, in order to reduce the thickness, on the one hand, it is necessary to select thin media to reduce the thickness of the PCB, and on the other hand, it is necessary to reduce the thickness of the relatively high magnetic components in the module power supply, which requires the reasonable design of the shape and size of the magnetic components.

[0004] Therefore, there is an urgent need to propose an ultra-thin DC / DC power supply module with wide input and large current output, which can be widely used in occasions with strict requirements on power supply thickness. Utility Model Content

[0005] Aiming at the defect that a power module adopting a full-bridge topology structure and applied to wide input voltage and large current output cannot be made thin, the utility model proposes a power module which can increase the power density of the module and reduce the thickness at the same time.

[0006] The technical solution of the utility model to solve the above technical problems is as follows:

[0007] A DC-DC power supply module comprises an input circuit, a transformer assembly and an output circuit connected in sequence; the transformer assembly comprises a first transformer and a second transformer, the input circuit and the output circuit both comprise two full-bridge circuits connected in parallel; the input end of the input circuit is respectively connected to an input DC power supply Vi n+ and Vi n-; the output end of the input circuit is respectively connected to the primary sides of the first transformer and the second transformer, the input end of the output circuit is respectively connected to the secondary sides of the first transformer and the second transformer, the output end of the output circuit is respectively connected to the output DC power supplies Vo+ and Vo-, two output inductors are connected in parallel to the output DC power supply Vo+, the two output inductors are magnetically integrated into an E-type magnetic core, and the coils of the two output inductors are respectively wound on the side columns of the E-type magnetic core in the same direction, the two full-bridge circuits of the input circuit are the first full-bridge circuit and the second full-bridge circuit; the two full-bridge circuits of the output circuit are the third full-bridge circuit and the fourth full-bridge circuit; the first full-bridge circuit includes a first bridge arm and a second bridge arm connected in parallel; the second full-bridge circuit includes a third bridge arm and a fourth bridge arm connected in parallel; the third full-bridge circuit includes a fifth bridge arm and a sixth bridge arm connected in parallel; the fourth full-bridge circuit includes a seventh bridge arm and an eighth bridge arm connected in parallel.

[0008] Furthermore, the two full-bridge circuits of the input circuit and the output circuit are both out of phase by 90 degrees.

[0009] The beneficial effect of the above further solution is that it can greatly reduce the maximum value of the magnetic flux of the middle column of the E-type magnetic core of the output inductor, thereby reducing the cross-sectional area of ​​the middle column, and effectively reducing the output ripple and the size of the output inductor.

[0010] Furthermore, the first transformer and the second transformer respectively adopt a first U-shaped magnetic core and a second U-shaped magnetic core, each power tube of the first full-bridge circuit is placed on one side of the first U-shaped magnetic core, each power tube of the third full-bridge circuit is placed on the other side of the first U-shaped magnetic core, each power tube of the second full-bridge circuit is placed on one side of the second U-shaped magnetic core, and each power tube of the fourth full-bridge circuit is placed on the other side of the second U-shaped magnetic core.

[0011] The beneficial effect of the above further solution is that since the power tube is placed close to the magnetic core and on the coil output end, the AC impedance of the coil can be effectively reduced, further reducing the AC loss of the coil, while also saving PCB space.

[0012] Furthermore, the primary side of the first transformer includes a first coil, and the secondary side includes a second coil, the two ends of the first coil are respectively connected to the midpoints of the first bridge arm and the second bridge arm, and a capacitor is also connected in series between the first bridge arm and the first coil; the two ends of the second coil are respectively connected to the midpoints of the fifth bridge arm and the sixth bridge arm; the primary side of the second transformer includes a third coil, and the secondary side includes a fourth coil, the two ends of the third coil are respectively connected to the midpoints of the third bridge arm and the fourth bridge arm, and a capacitor is also connected in series between the third bridge arm and the third coil; the two ends of the fourth coil are respectively connected to the midpoints of the seventh bridge arm and the eighth bridge arm.

[0013] The beneficial effects of the above further scheme are: reducing the size of the magnetic core, the coils are divided into two groups and wound on the two legs of the U-shaped magnetic core respectively, the magnetic core package is reduced, the coil loss is reduced, and at the same time, since most of the coils are exposed to the air, the thermal resistance of the coils is further reduced.

[0014] Furthermore, the output DC power supply Vo+ and Vo- terminals of the output circuit are connected in parallel with an output capacitor.

[0015] The beneficial effect of the above further solution is to make the output DC more stable.

[0016] Further, the first bridge arm includes a first power tube Q1 and a third power tube Q3 connected in series;

[0017] The second bridge arm includes a second power tube Q2 and a fourth power tube Q4 connected in series;

[0018] The third bridge arm includes a fifth power tube Q5 and a seventh power tube Q7 connected in series;

[0019] The fourth bridge arm includes a sixth power tube Q6 and an eighth power tube Q8 connected in series;

[0020] The fifth bridge arm includes a ninth power tube Q9 and an eleventh power tube Q11 connected in series;

[0021] The sixth bridge arm includes a tenth power tube Q10 and a twelfth power tube Q12 connected in series;

[0022] The seventh bridge arm includes a thirteenth power tube Q13 and a fifteenth power tube Q15 connected in series;

[0023] The eighth bridge arm includes a fourteenth power tube Q14 and a sixteenth power tube Q16 connected in series.

[0024] The present application adopts the above technical solution, which has at least the following beneficial effects:

[0025] Compared with the power supply using the traditional hard switch topology design such as half-bridge / full-bridge / Buck, the input circuit and output circuit of this utility model split a full bridge into two full bridges in parallel while ensuring the reliability of the power supply. The input and output currents can be made larger, and the power density can be made higher. At the same time, because of the use of magnetic integration technology, the output inductor is magnetically integrated onto an E-type magnetic core. In addition, when performing software configuration, the upper and lower full bridges are staggered by 90 degrees, which can greatly reduce the maximum value of the magnetic flux of the middle column of the output inductor E-type magnetic core, which can effectively reduce the loss and further reduce the cross-sectional area of ​​the middle column. The size of the magnetic core is made as small as possible, the transformer uses two U-shaped magnetic cores, and all magnetic components use thin bases. Reducing the module height can effectively reduce the size of the magnetic components and help reduce the thickness of the module. The power module can be made thinner and has a wider range of applications.

[0026] This solution can effectively reduce the thickness of the module power supply module and improve the power density of the power supply. It is relatively simple to implement and can be widely used in ultra-thin module power supply applications with wide input and large current output. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is the topological structure circuit diagram of the utility model;

[0028] Figure 2 This is a structural diagram of the output inductor of the utility model. DETAILED DESCRIPTION

[0029] Now, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be understood that the embodiments shown and described in the accompanying drawings are merely exemplary, intended to explain the principles and spirit of the present invention, rather than to limit the scope of the present invention.

[0030] In view of the defect that the height of a module power supply with wide input voltage and large current output cannot be made thin, the utility model proposes a DC-DC power supply module that can reduce the thickness of the module while improving the power density of the module. The input circuit and the output circuit both split a full bridge into two full bridges in parallel, which can effectively reduce the loss and further improve the output current capacity, thereby improving the power density of the module; the transformer adopts two U-shaped cores, and the output inductor is magnetically integrated onto an E-shaped core. All magnetic components use a thin base, and reducing the module height can effectively reduce the size of the magnetic components and help reduce the thickness of the module.

[0031] like Figure 1-2 As shown, this embodiment provides a DC-DC power supply module, including an input circuit, a transformer assembly and an output circuit connected in sequence.

[0032] Among them, the transformer assembly includes a first transformer and a second transformer, the input circuit includes two full-bridge circuits connected in parallel; the output circuit includes two full-bridge circuits connected in parallel; the input end of the input circuit is respectively connected to the input DC power supplies Vin+ and Vin-; the output end of the input circuit is respectively connected to the primary sides of the first transformer and the second transformer, the input end of the output circuit is respectively connected to the secondary sides of the first transformer and the second transformer, the output end of the output circuit is respectively connected to the output DC power supplies Vo+ and Vo-, two output inductors are connected in parallel to the output DC power supply Vo+, the two output inductors are magnetically integrated into an E-type magnetic core, and the coils of the two output inductors are respectively wound on the side columns of the E-type magnetic core in the same direction.

[0033] like Figure 2 As shown in the figure, the output inductor adopts an E-type magnetic core with magnetic integration technology, and the two output inductor coils are respectively wound on the side columns of the E-type magnetic core. Since the output inductor adopts magnetic integration technology, the two are merged into one, so it is placed in the middle of the upper and lower secondary full-bridge rectifiers / full-wave rectifiers, and the coils are wound on the side columns of the E-type magnetic core in the same direction. Considering the output parallel connection, in order to ensure the current sharing effect, the winding of the transformer and the output inductor coil should be as symmetrical as possible. In addition, when performing software configuration, the upper and lower full-bridges are staggered by 90 degrees, which can greatly reduce the maximum value of the magnetic flux in the middle column of the output inductor E-type magnetic core, and thus reduce the cross-sectional area of ​​the middle column.

[0034] Specifically, the two full-bridge circuits of the input circuit are the first full-bridge circuit and the second full-bridge circuit; the two full-bridge circuits of the output circuit are the third full-bridge circuit and the fourth full-bridge circuit; the first full-bridge circuit includes a first bridge arm and a second bridge arm connected in parallel; the second full-bridge circuit includes a third bridge arm and a fourth bridge arm connected in parallel; the third full-bridge circuit includes a fifth bridge arm and a sixth bridge arm connected in parallel; the fourth full-bridge circuit includes a seventh bridge arm and an eighth bridge arm connected in parallel.

[0035] The first bridge arm includes a first power tube Q1 and a third power tube Q3 connected in series; the second bridge arm includes a second power tube Q2 and a fourth power tube Q4 connected in series; the third bridge arm includes a fifth power tube Q5 and a seventh power tube Q7 connected in series; the fourth bridge arm includes a sixth power tube Q6 and an eighth power tube Q8 connected in series. The fifth bridge arm includes a ninth power tube Q9 and an eleventh power tube Q11 connected in series; the sixth bridge arm includes a tenth power tube Q10 and a twelfth power tube Q12 connected in series; the seventh bridge arm includes a thirteenth power tube Q13 and a fifteenth power tube Q15 connected in series; the eighth bridge arm includes a fourteenth power tube Q14 and a sixteenth power tube Q16 connected in series.

[0036] Among them, one end of the first power tube Q1, the second power tube Q2, the fifth power tube Q5, and the sixth power tube Q6 are all connected to the positive electrode Vin+ of the DC power supply, and one end of the third power tube Q3, the fourth power tube Q4, the seventh power tube Q7, and the eighth power tube Q8 are all connected to the negative electrode Vin- of the DC power supply. One end of the ninth power tube Q9, the tenth power tube Q10, the thirteenth power tube Q13, and the fourteenth power tube Q14 are all connected to the output DC power supply Vo+; one end of the twelfth power tube Q12, the fifteenth power tube Q15, the eleventh power tube Q11, and the sixteenth power tube Q16 are all connected to the output DC power supply Vo-

[0037] The third full-bridge circuit and the fourth full-bridge circuit are connected in parallel, which is suitable for low-voltage and high-current output applications. In order to ensure the parallel current sharing effect, the coils should be wound symmetrically as much as possible during PCB design. In order to make the output DC power smoother when the parallel connection is adopted, an output capacitor is also connected in parallel at the output end of the output circuit.

[0038] In this embodiment, all power tubes are fully controlled power electronic devices, such as metal oxide semiconductor field effect tubes (MOS) or insulated gate bipolar transistors (IGBT). Figure 1 The technical solution provided by the embodiment of the present application is introduced by taking the MOS power tube as an example, but the present application does not limit the type of switching transistor, and other corresponding electronic components can also be used to implement it. These simple replacements do not deviate from the protection scope of the present application.

[0039] Specifically, when MOS tubes are used, all bridge arms are connected in a manner of connecting the source and the drain in series, wherein the drains of the first power tube Q1, the second power tube Q2, the fifth power tube Q5, and the sixth power tube Q6 of the input circuit are all connected to the positive electrode of the input DC power supply, and the sources of the third power tube Q3, the fourth power tube Q4, the seventh power tube Q7, and the eighth power tube Q8 are all connected to the negative electrode of the input DC power supply.

[0040] The first transformer and the second transformer use the first U-shaped magnetic core and the second U-shaped magnetic core respectively, each power tube of the first full-bridge circuit is placed on one side of the first U-shaped magnetic core, each power tube of the third full-bridge circuit is placed on the other side of the first U-shaped magnetic core, each power tube of the second full-bridge circuit is placed on one side of the second U-shaped magnetic core, and each power tube of the fourth full-bridge circuit is placed on the other side of the second U-shaped magnetic core. Since the power tube is placed close to the magnetic core and on the coil outlet, the AC impedance of the coil can be effectively reduced, further reducing the AC loss of the coil, while also saving PCB space.

[0041] The first transformer and the second transformer have the same structure. The primary side of the first transformer Tr1 includes a first coil, and the secondary side includes a second coil. The two ends of the first coil are respectively connected to the midpoints of the first bridge arm and the second bridge arm, and a capacitor C1 is also connected in series between the first bridge arm and the first coil; the two ends of the second coil are respectively connected to the midpoints of the fifth bridge arm and the sixth bridge arm; the primary side of the second transformer Tr2 includes a third coil, and the secondary side includes a fourth coil. The two ends of the third coil are respectively connected to the midpoints of the third bridge arm and the fourth bridge arm, and a capacitor C2 is also connected in series between the third bridge arm and the third coil; the two ends of the fourth coil are respectively connected to the midpoints of the seventh bridge arm and the eighth bridge arm.

[0042] In this embodiment, by connecting the bridge arm units on both sides through the first transformer and the second transformer, DC / DC conversion of various ratio DC voltages such as large ratio and small ratio can be realized, thereby completing the DC / DC energy interaction work in high-voltage applications, solving the problem that the DC / DC converter in the prior art cannot be adapted to high-voltage applications.

[0043] The output inductor is combined into one by using magnetic integration technology, so it is placed in the middle of the upper and lower secondary full-bridge rectifiers / full-wave rectifiers, and the coils are wound in the same direction on the side columns of the E-type magnetic core. Considering the parallel output, in order to ensure the current sharing effect, the winding of the transformer and the output inductor coil should be as symmetrical as possible.

[0044] In addition, when performing software configuration, the upper and lower full bridges are staggered by 90 degrees, which can greatly reduce the maximum value of the magnetic flux in the middle column of the output inductor E-type magnetic core, thereby reducing the cross-sectional area of ​​the middle column.

[0045] The power stages of the utility model can effectively reduce losses by connecting in parallel, and the output current capacity can be further improved, thereby improving the power density of the module; the output inductor can effectively reduce the size of the magnetic component by magnetic integration, and at the same time help to reduce the thickness of the module.

[0046] The working principle in one working cycle is:

[0047] In one working cycle, the first power tube Q1 and the fourth power tube Q4 are turned on and off at the same time, the second power tube Q2 and the third power tube Q3 are turned on and off at the same time and are 180 degrees out of phase with the first power tube Q1 and the third power tube Q3, the ninth power tube Q9 and the twelfth power tube Q12 are complementary to the first power tube Q1 and the fourth power tube Q4 in output, the tenth power tube Q10 and the eleventh power tube Q11 are complementary to the second power tube Q2 and the third power tube Q3 in output; the fifth power tube Q5 and the eighth power tube Q8 are turned on and off at the same time, and the fifth power tube Q5 is 90 degrees out of phase with the first power tube Q1, the sixth power tube Q6 and the seventh power tube Q7 are turned on and off at the same time, the thirteenth power tube Q13 and the sixteenth power tube Q16 are complementary to the fifth power tube Q5 and the eighth power tube Q8 in output, and the fourteenth power tube Q14 and the fifteenth power tube Q15 are complementary to the sixth power tube Q6 and the seventh power tube Q7 in output. The energy on the input side is transferred to the output side through the capacitors connected in parallel at the input end, transformers Tr1 and Tr2, and then outputs stable DC power through the output filter capacitor.

[0048] The circuit provided in the utility model is also applicable to topology circuits with half-bridge / BUCK input circuits and full-wave output circuits.

[0049] The utility model is improved on the basis of the traditional topology, splitting a half bridge / full bridge on the primary side into two half bridges / full bridges in parallel, splitting a full bridge rectifier / full wave rectifier on the secondary side into two full bridge rectifiers / full wave rectifiers in parallel; the two half bridges or full bridges on the primary side of the transformer are staggered by 90 degrees, or the power level is two BUCKs in parallel, and the two BUCKs are staggered by 90 degrees; the two transformers use a slender thin base U-shaped magnetic core; the 2-way output inductor is combined into an E-shaped magnetic core, and the inductor coils are respectively wound on the side columns of the E-shaped magnetic core in the same direction. The module height can be greatly reduced, the power density of the module can be improved, and it is relatively simple to implement, and can be widely used in occasions with strict requirements on the thickness of the power supply.

[0050] Compared with power supplies designed with traditional hard-switching topologies such as half-bridge / full-bridge / Buck, the power module designed using this solution can have a larger output current and a higher power density while ensuring power reliability. At the same time, because the magnetic core size is made as small as possible using magnetic integration technology, the power module can be made thinner and have a wider range of applications.

[0051] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A DC-DC power supply module, characterized in that: The invention comprises an input circuit, a transformer assembly and an output circuit connected in sequence; the transformer assembly comprises a first transformer and a second transformer, and the input circuit and the output circuit both comprise two full-bridge circuits connected in parallel; the input end of the input circuit is respectively connected to input DC power supplies Vin+ and Vin-; the output end of the input circuit is respectively connected to the primary sides of the first transformer and the second transformer, the input end of the output circuit is respectively connected to the secondary sides of the first transformer and the second transformer, the output end of the output circuit is respectively connected to output DC power supplies Vo+ and Vo-, and two full-bridge circuits are connected in parallel to the output DC power supply Vo+. Output inductor, the two output inductors are magnetically integrated into an E-type magnetic core, and the coils of the two output inductors are respectively wound on the side columns of the E-type magnetic core in the same direction, the two full-bridge circuits of the input circuit are a first full-bridge circuit and a second full-bridge circuit; the two full-bridge circuits of the output circuit are a third full-bridge circuit and a fourth full-bridge circuit; the first full-bridge circuit includes a first bridge arm and a second bridge arm connected in parallel; the second full-bridge circuit includes a third bridge arm and a fourth bridge arm connected in parallel; the third full-bridge circuit includes a fifth bridge arm and a sixth bridge arm connected in parallel; the fourth full-bridge circuit includes a seventh bridge arm and an eighth bridge arm connected in parallel.

2. The DC-DC power supply module according to claim 1, characterized in that: The two full-bridge circuits of the input circuit and the output circuit are both out of phase by 90 degrees.

3. The DC-DC power supply module according to claim 1, characterized in that: The first transformer and the second transformer respectively adopt a first U-shaped magnetic core and a second U-shaped magnetic core, each power tube of the first full-bridge circuit is placed on one side of the first U-shaped magnetic core, each power tube of the third full-bridge circuit is placed on the other side of the first U-shaped magnetic core, each power tube of the second full-bridge circuit is placed on one side of the second U-shaped magnetic core, and each power tube of the fourth full-bridge circuit is placed on the other side of the second U-shaped magnetic core.

4. The DC-DC power supply module according to claim 1, characterized in that: The primary side of the first transformer includes a first coil, and the secondary side includes a second coil. The two ends of the first coil are respectively connected to the midpoints of the first bridge arm and the second bridge arm, and a capacitor is also connected in series between the first bridge arm and the first coil; the two ends of the second coil are respectively connected to the midpoints of the fifth bridge arm and the sixth bridge arm; the primary side of the second transformer includes a third coil, and the secondary side includes a fourth coil. The two ends of the third coil are respectively connected to the midpoints of the third bridge arm and the fourth bridge arm, and a capacitor is also connected in series between the third bridge arm and the third coil; the two ends of the fourth coil are respectively connected to the midpoints of the seventh bridge arm and the eighth bridge arm.

5. The DC-DC power supply module according to claim 1, characterized in that: The output DC power supply Vo+ and Vo- terminals of the output circuit are connected in parallel with an output capacitor.

6. The DC-DC power supply module according to claim 1, characterized in that: The first bridge arm includes a first power tube Q1 and a third power tube Q3 connected in series; The second bridge arm includes a second power tube Q2 and a fourth power tube Q4 connected in series; The third bridge arm includes a fifth power tube Q5 and a seventh power tube Q7 connected in series; The fourth bridge arm includes a sixth power tube Q6 and an eighth power tube Q8 connected in series; The fifth bridge arm includes a ninth power tube Q9 and an eleventh power tube Q11 connected in series; The sixth bridge arm includes a tenth power tube Q10 and a twelfth power tube Q12 connected in series; The seventh bridge arm includes a thirteenth power tube Q13 and a fifteenth power tube Q15 connected in series; The eighth bridge arm includes a fourteenth power tube Q14 and a sixteenth power tube Q16 connected in series.

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