Rectifier diode parallel connection current sharing DCDC circuit
By adding inductor branches to the DCDC circuit, the current uneven problem caused by the on-voltage drop of the fast recovery diode is solved, current equalization is achieved, circuit power and stability are improved, and circuit design is simplified.
Patent Information
- Application Number
- CN202421263899.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-04
- Publication Date
- 2024-12-24
- Estimated Expiration
- 2034-06-04
AI Technical Summary
The conduction voltage drop of the fast recovery diode in existing DCDC circuits is a negative temperature coefficient, which leads to positive feedback when used in parallel, increasing the risk of diode failure and affecting the module power increase.
Add an inductor branch between each diode branch and the connection end of the transformer to reduce the voltage difference between the two series diodes in the diode branch to achieve a current sharing effect.
By increasing the inductance branch, the voltage difference in the diode branch is reduced, the current equalization is improved, the risk of diode failure is reduced, the power performance of the DCDC circuit is improved, the circuit structure is simplified, and the device cost is reduced.
Smart Images
Figure CN222234696U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of switch power supply modules, and more specifically to a DCDC circuit with rectifier diodes connected in parallel to equalize current. Background Art
[0002] Nowadays, as the power demand of switching power supply modules is increasing, the DCDC circuit generally adopts an isolated topology, and the post-rectifier adopts a fast recovery diode. The conduction voltage drop of the fast recovery diode is a negative temperature coefficient. The typical temperature-voltage drop curve is as follows: Figure 1 As shown, the higher the temperature, the smaller the pressure drop. Figure 2 : is a circuit schematic diagram of a DCDC circuit in the prior art. Figure 2 As shown, when the fast recovery diodes are used in parallel, assuming that the voltage drop of the fast recovery diode D1 is smaller than that of the fast recovery diode D3, and the current I1 is greater than the current I2, the fast recovery diode D1 has a higher temperature and a smaller voltage drop, so the current flowing through the fast recovery diode D1 is larger, which will form a positive feedback, resulting in a high risk of failure of the fast recovery diode D1 due to excessive current, which poses a great challenge to increasing the power of the module. Utility Model Content
[0003] The technical problem to be solved by the utility model is that, in view of the above-mentioned defects of the prior art, a DCDC circuit with parallel rectifier diodes for current equalization is provided, which cleverly reduces the voltage difference between the two series-connected diodes in each diode branch by adding an inductor branch between the connection end of each diode branch and the transformer, thereby achieving a good current equalization effect.
[0004] The technical solution adopted by the utility model to solve its technical problems is: constructing a DCDC circuit with parallel rectifier diodes for current sharing, comprising: a transformer module, a primary input module arranged on the primary side of the transformer module, and a secondary output module arranged on the secondary side of the transformer module; the secondary output module comprises 2N diode branches, 2N inductor branches and an output unit; the 2N diode branches are all connected in parallel at both ends of the output unit; each of the diode branches comprises two diodes connected in series; the first end of each of the inductor branches is connected to the midpoint of a diode branch one by one, and the second end is connected to the secondary winding of the transformer module; wherein N is a positive integer.
[0005] In the DCDC circuit with rectifier diodes connected in parallel for current sharing described in the utility model, the inductor branch includes at least one inductor, and the diodes include fast recovery diodes, Schottky diodes and SIC diodes.
[0006] In the DCDC circuit with rectifier diodes connected in parallel for current sharing described in the utility model, the inductor is an independent inductor, a lead inductor or a leakage inductor of the transformer module.
[0007] In the DCDC circuit with parallel rectifier diodes for current sharing described in the utility model, the transformer module includes a secondary winding, the first end of the secondary winding is connected to the second ends of N inductor branches; the second end of the secondary winding is connected to the second ends of another N inductor branches; the first end of each inductor branch is connected to the midpoint of a diode branch one by one.
[0008] In the DCDC circuit with parallel rectifier diodes for current sharing described in the utility model, the transformer module includes N secondary windings, each secondary winding includes a first end and a second end; 2N ends of the N secondary windings are connected to the second ends of 2N inductor branches in a one-to-one correspondence; and the first end of each inductor branch is connected to the midpoint of a diode branch in a one-to-one correspondence.
[0009] In the DCDC circuit with rectifier diodes connected in parallel for current sharing described in the utility model, the output unit includes an output capacitor.
[0010] In the DCDC circuit with parallel-connected rectifier diodes for current sharing described in the utility model, the output unit includes an output capacitor and an output inductor connected in series with each other.
[0011] In the DCDC circuit with parallel current sharing of rectifier diodes described in the utility model, the primary input module includes an input capacitor, a first switch tube, a second switch tube, a third switch tube and a fourth switch tube; the control ends of the first switch tube, the second switch tube, the third switch tube and the fourth switch tube receive a control signal, the first end of the first switch tube is connected to the second end of the second switch tube, and the second end is connected to the second end of the third switch tube and the first end of the input capacitor, the first end of the second switch tube is connected to the first end of the fourth switch tube and the second end of the input capacitor, and the first end of the third switch tube is connected to the second end of the fourth switch tube.
[0012] In the DCDC circuit with parallel rectifier diodes for current sharing described in the utility model, the primary input module further includes a resonant capacitor and a resonant inductor; the first end of the resonant capacitor is connected to the first end of the primary winding of the transformer module, and the second end is connected to the first end of the first switch tube and the second end of the second switch tube via the resonant inductor; the second end of the primary winding of the transformer module is connected to the first end of the third switch tube and the second end of the fourth switch tube.
[0013] In the DCDC circuit with parallel rectifier diodes for current sharing described in the utility model, the primary input module further includes a resonant capacitor and a resonant inductor; the first end of the resonant inductor is connected to the first end of the primary winding of the transformer module, and the second end is connected to the first end of the first switch tube and the second end of the second switch tube via the resonant capacitor; the second end of the primary winding of the transformer module is connected to the first end of the third switch tube and the second end of the fourth switch tube.
[0014] The DCDC circuit for current equalization by connecting rectifier diodes in parallel of the utility model is cleverly implemented by adding an inductor branch between each diode branch and the connection end of the transformer, thereby reducing the voltage difference between the two series diodes in each diode branch, thereby achieving a good current equalization effect, which is beneficial to the power improvement of the DCDC circuit. The entire circuit structure is simple and easy to implement, and the device cost is low, and it is easy to promote and apply. In addition, the DCDC circuit for current equalization by connecting rectifier diodes in parallel of the utility model is suitable for various DCDC circuits, such as LLC topology, full bridge or phase-shifted full bridge topology, and has a wide range of application scenarios. Furthermore, the inductor branch can be realized by an independent inductor, PCB trace inductance or transformer leakage inductance, so the circuit is simple and reliable. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:
[0016] Figure 1 It is a typical temperature-voltage drop curve of a fast recovery diode in the prior art;
[0017] Figure 2 It is a circuit schematic diagram of a DCDC circuit in the prior art;
[0018] Figure 3 It is a principle block diagram of a preferred embodiment of a DCDC circuit for current equalization by connecting rectifier diodes in parallel in the utility model;
[0019] Figure 4 It is a circuit diagram of a preferred embodiment of a DCDC circuit for current equalization by connecting rectifier diodes in parallel in the utility model;
[0020] Figure 5 It is a circuit diagram of another preferred embodiment of the DCDC circuit of the utility model in which rectifier diodes are connected in parallel and current is shared;
[0021] Figure 6 It is a circuit diagram of another preferred embodiment of the DCDC circuit of the utility model in which rectifier diodes are connected in parallel and current is shared;
[0022] Figure 7 It is a circuit diagram of another preferred embodiment of the DCDC circuit of the utility model in which rectifier diodes are connected in parallel and current is shared;
[0023] Figure 8 It is a circuit diagram of another preferred embodiment of the DCDC circuit with parallel-connected rectifier diodes and current sharing of the utility model. DETAILED DESCRIPTION
[0024] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.
[0025] Figure 3 FIG. 1 is a principle block diagram of a preferred embodiment of a DCDC circuit for current equalization with parallel connection of rectifier diodes of the utility model. Figure 3 As shown, the DCDC circuit for current equalization of rectifier diodes in parallel of the present invention comprises: a transformer module 200, a primary input module 100 arranged on the primary side of the transformer module 200, and a secondary output module 300 arranged on the secondary side of the transformer module 200. The secondary output module 300 comprises 2N diode branches 321, 322, ... 32 (2N), 2N inductor branches 311, 312, ... 31 (2N) and an output unit 330.
[0026] like Figure 3 As shown, the 2N diode branches 321, 322, ...32 (2N) are all connected in parallel at both ends of the output unit 330; each of the diode branches 321, 322, ...32 (2N) includes two diodes connected in series with each other; the first end of each of the inductor branches 311, 312, ...31 (2N) is connected to the midpoint of one of the diode branches 321, 322, ...32 (2N) one by one, and the second end is connected to the secondary winding of the transformer module; wherein N is a positive integer.
[0027] For example, the first end of the inductor branch 311 is connected to the midpoint of the diode branch 321, and the second end is connected to the secondary winding of the transformer module 200; the first end of the inductor branch 312 is connected to the midpoint of the diode branch 322, and the second end is connected to the secondary winding of the transformer module 200; and so on, the first end of the inductor branch 31 (2N) is connected to the midpoint of the diode branch 32 (2N), and the second end is connected to the secondary winding of the transformer module 200.
[0028] In a preferred embodiment of the present invention, each inductor branch 311, 312, ... 31 (2N) includes at least one inductor. The inductor can be an independent inductor, a lead inductor (such as a PCB lead inductor) or a leakage inductor of the transformer module 200. The diode is a fast recovery diode. The midpoint of the diode branch 321, 322, ... 32 (2N) is the connection point of the two fast recovery diodes connected in series. In other preferred embodiments of the present invention, the diode can also be a Schottky diode and a SIC diode. For Schottky diodes and SIC diodes, the DCDC circuit of the present invention with parallel rectifier diodes and current sharing is also applicable, and its principle is similar to that of the fast recovery diode, which will not be repeated here.
[0029] In a preferred embodiment of the utility model, the transformer module 200 may include a secondary winding, a first end of the secondary winding being connected to the second ends of N of the inductance branches 311, 312, ...31N; a second end of the secondary winding being connected to the second ends of another N of the inductance branches 31 (N+1), 31 (N+2), ...31 (2N); and a first end of each of the inductance branches 311, 312, ...31 (2N) being connected one-to-one to the midpoint of one of the diode branches 321, 322, ...32 (2N).
[0030] In a preferred embodiment of the present invention, the transformer module 200 may include N secondary windings, each secondary winding including a first end and a second end; the 2N ends of the N secondary windings are connected one-to-one to the second ends of the 2N inductor branches 311, 312, ...31 (2N); the first end of each of the inductor branches 311, 312, ...31 (2N) is connected one-to-one to the midpoint of one of the diode branches 321, 322, ...32 (2N).
[0031] In a preferred embodiment of the present invention, the output unit 330 may include a filter capacitor and / or a filter inductor. In a preferred embodiment of the present invention, the primary input module 100 may include a switch tube full-bridge topology, a half-bridge topology, etc. Here, the output unit 330 and the primary input module 100 may adopt any known device, module or unit structure in the prior art, which all fall within the protection scope of the present invention.
[0032] In the present invention, in view of the problem that the negative temperature coefficient of the conduction voltage drop of the fast recovery diode leads to the inability to balance the current when used in parallel, a series inductor is added to the diode branch to increase the impedance of the branch, thereby reducing the voltage difference between the two series diodes in each diode branch, thereby achieving a good current balancing effect, which is beneficial to the power improvement of the DCDC circuit. The entire circuit structure is simple, easy to implement, and the device cost is low, and it is easy to promote and apply.
[0033] Figure 4 FIG. 1 is a circuit diagram of a preferred embodiment of a DCDC circuit for current equalization with rectifier diodes connected in parallel in the utility model. Figure 4 As shown, the DCDC circuit with parallel rectifier diodes for current sharing includes: a transformer module 200 , a primary input module 100 arranged on the primary side of the transformer module 200 , and a secondary output module 300 arranged on the secondary side of the transformer module 200 .
[0034] like Figure 4 As shown, the secondary output module 300 includes four diode branches formed by diodes D1-D8, four inductor branches formed by inductors L1-L4, and an output capacitor Co. The transformer module includes a transformer T1. The primary input module 100 includes a full-bridge module formed by an input capacitor Ci1 and switch tubes Q1-Q4, and a resonant unit formed by a resonant inductor L11 and a resonant capacitor Ci2.
[0035] like Figure 4 As shown, the control ends of the switch tubes Q1, Q2, Q3 and Q4 receive control signals, the first end of the switch tube Q1 is connected to the second end of the switch tube Q2, the second end is connected to the second end of the switch tube Q3 and the first end of the input capacitor Ci1, the first end of the switch tube Q2 is connected to the first end of the switch tube Q4 and the second end of the input capacitor Ci1, and the second end of the switch tube Q3 is connected to the second end of the switch tube Q4. The first end of the resonant capacitor Ci2 is connected to the first end of the primary winding of the transformer T1, and the second end is connected to the first end of the switch tube Q1 and the second end of the switch tube Q2 through the resonant inductor L11; the second end of the primary winding of the transformer T1 is connected to the second end of the switch tube Q3 and the second end of the switch tube Q4. Of course, in other preferred embodiments of the utility model, the positions of the resonant capacitor Ci2 and the resonant inductor L11 can be interchanged. The switch tubes Q1-Q4 can be IGBTs or MOS tubes.
[0036] like Figure 4As shown, the first end of the secondary winding of the transformer T1 is connected to the midpoint of the diode branch formed by diodes D1 and D2 through the inductor L1, and is connected to the midpoint of the diode branch formed by diodes D3 and D4 through the inductor L2. The second end of the secondary winding of the transformer T1 is connected to the midpoint of the diode branch formed by diodes D5 and D6 through the inductor L3, and is connected to the midpoint of the diode branch formed by diodes D7 and D8 through the inductor L4. The four diode branches formed by diodes D1-D8 are all connected in parallel at both ends of the output capacitor Co.
[0037] Of course, in other preferred embodiments of the utility model, other connection relationships can be adopted, such as the first end of the secondary winding of the transformer T1 is connected to the midpoint of the diode branch composed of diodes D1 and D2 through the inductor L1, and is connected to the midpoint of the diode branch composed of diodes D5 and D6 through the inductor L2. The second end of the secondary winding of the transformer T1 is connected to the midpoint of the diode branch composed of diodes D3 and D4 through the inductor L3, and is connected to the midpoint of the diode branch composed of diodes D7 and D8 through the inductor L4. For another example, the first end of the secondary winding of the transformer T1 is connected to the midpoint of the diode branch composed of diodes D3 and D4 through the inductor L1, and is connected to the midpoint of the diode branch composed of diodes D5 and D6 through the inductor L2. The second end of the secondary winding of the transformer T1 is connected to the midpoint of the diode branch composed of diodes D1 and D2 through the inductor L3, and is connected to the midpoint of the diode branch composed of diodes D7 and D8 through the inductor L4.
[0038] Those skilled in the art know that various connection relationships can be adopted as long as they can satisfy that the first end of the secondary winding is connected to the second ends of N of the inductance branches 311, 312, ...31N; the second end of the secondary winding is connected to the second ends of the other N inductance branches 31 (N+1), 31 (N+2), ...31 (2N); the first end of each of the inductance branches 311, 312, ...31 (2N) is connected one-to-one to the midpoint of one of the diode branches 321, 322, ...32 (2N).
[0039] exist Figure 4 In the preferred embodiment shown, the inductors L1 - L4 may be independent inductors, PCB lead inductors, or transformer leakage inductors.
[0040] Combine the following Figure 4 The principle of the utility model is described as follows. An inductor is connected in series on the branch line of the parallel secondary circuit. Figure 4Taking the LLC circuit shown as an example, assuming that the voltage drop of diode D1 is Vf1 and the voltage drop of diode D3 is Vf2, the sum of the inductance voltage drops of the diode branch where diode D1 is located and its corresponding inductance L1 is equal to the sum of the inductance voltage drops of the diode branch where diode D3 is located and its corresponding inductance L2. According to the angular velocity formula w=2π*f, f is the frequency of the current. According to the parallel voltage is equal, that is, w*L1*I1+Vf1=w*L2*I2+Vf2; when the inductance L1 and the inductance L2 are equal and both equal to L, according to L1=L2=L; it is derived that I1-I2=(Vf2-Vf1) / (w*L). Therefore, it can be seen from the above formula that the difference in branch current is inversely proportional to the frequency and inductance. When the frequency f and the inductance L take appropriate values, the current difference between the diode branch where diode D1 is located and the diode branch where diode D3 is located can be controlled to a smaller value to achieve a better current sharing effect.
[0041] Therefore, when an inductor branch with suitable inductance is connected between each diode branch and the connection end of the transformer, and the frequency of the control signal received by the switch tubes Q1-Q4 is controlled, the current difference between the diode branch where the diode D1 is located and the diode branch where the diode D3 is located can be controlled to a smaller value, thereby achieving a better current sharing effect.
[0042] Therefore, the utility model addresses the problem of the inability to balance the current when used in parallel due to the negative temperature coefficient of the conduction voltage drop of the fast recovery diode. A series inductor is added to the diode branch to increase the impedance of the branch. The higher the frequency and the greater the inductance, the better the current balance. This inductor can be an independent inductor, a PCB trace inductor, a transformer leakage inductor, etc. It is simple and reliable, and can realize the parallel use of two to N fast recovery diodes, which is beneficial to increase the power of the module.
[0043] Figure 5 FIG. 1 is a circuit diagram of another preferred embodiment of the DCDC circuit of the utility model in which rectifier diodes are connected in parallel to share the current. Figure 5 In the preferred embodiment shown, it is Figure 4 Similar to the preferred embodiment shown, the secondary output module 300 includes 2N diode branches formed by diodes D1-D4N, 2N inductor branches formed by inductors L1-L2N, and an output capacitor Co. The transformer module includes a transformer T1. The primary input module 100 includes a full-bridge module formed by input capacitor Ci1 and switch tubes Q1-Q4, and a resonant unit formed by a resonant inductor L11 and a resonant capacitor Ci2. The transformer T1 includes a secondary winding.
[0044] exist Figure 5In the preferred embodiment shown, the first end of the secondary winding of the transformer T1 is connected to the midpoint of the diode branch formed by the diodes D1 and D2 through the inductor L1, connected to the midpoint of the diode branch formed by the diodes D3 and D4 through the inductor L2, and so on, ..., connected to the midpoint of the diode branch formed by the diodes D2N-1 and D2N through the inductor LN. The second end of the secondary winding of the transformer T1 is connected to the midpoint of the diode branch formed by the diodes D2N+1 and D2N+2 through the inductor LN+1, connected to the midpoint of the diode branch formed by the diodes D2N+3 and DN+3 through the inductor LN+2, and so on, ..., connected to the midpoint of the diode branch formed by the diodes D4N-1 and D4N through the inductor L2N. The 2N diode branches formed by the diodes D1-D4N are all connected in parallel at both ends of the output capacitor Co.
[0045] exist Figure 5 In the preferred embodiment shown, the inductors L1-L2N can be independent inductors, PCB lead inductors, transformer leakage inductors. Those skilled in the art know that various connection relationships can be adopted as long as they can meet the conditions that the first end of the secondary winding is connected to the second ends of the N inductor branches 311, 312, ... 31N; the second end of the secondary winding is connected to the second ends of the other N inductor branches 31 (N+1), 31 (N+2), ... 31 (2N); the first end of each inductor branch 311, 312, ... 31 (2N) is connected to the midpoint of one of the diode branches 321, 322, ... 32 (2N) in a one-to-one correspondence.
[0046] Figure 6 FIG. 1 is a circuit diagram of another preferred embodiment of a DCDC circuit of the utility model in which rectifier diodes are connected in parallel to share current. Figure 6 In the preferred embodiment shown, it is Figure 4 Similar to the preferred embodiment shown, the secondary output module 300 includes 2N diode branches consisting of diodes D1-D4N, 2N inductor branches consisting of inductors L1-L2N, and an output capacitor Co. The transformer module includes a transformer T1. The primary input module 100 includes a full-bridge module consisting of an input capacitor Ci1 and switch tubes Q1-Q4, and a resonant unit consisting of a resonant inductor L11 and a resonant capacitor Ci2. The transformer module includes a transformer T1. Figure 6 In the preferred embodiment shown, the transformer T1 includes N secondary windings.
[0047] like Figure 6As shown, the first end of the first secondary winding of the transformer T1 is connected to the midpoint of the diode branch formed by diodes D1 and D2 via the inductor L1, and the first end of the second secondary winding of the transformer T1 is connected to the midpoint of the diode branch formed by diodes D3 and D4 via the inductor L2; the second end of the first secondary winding of the transformer T1 is connected to the midpoint of the diode branch formed by diodes D5 and D6 via the inductor L3, and the second end of the second secondary winding of the transformer T1 is connected to the midpoint of the diode branch formed by diodes D7 and D8 via the inductor L4, and so on, ..., the second end of the Nth secondary winding of the transformer T1 is connected to the midpoint of the diode branch formed by diodes D4N-1 and D4N via the inductor L2N. The 2N diode branches formed by diodes D1-D4N are all connected in parallel at both ends of the output capacitor Co.
[0048] exist Figure 6 In the preferred embodiment shown, the inductors L1-L2N can be independent inductors, PCB lead inductors, transformer leakage inductors. Those skilled in the art know that various connection relationships can be adopted as long as they can meet the conditions that the first end of the secondary winding is connected to the second ends of the N inductor branches 311, 312, ... 31N; the second end of the secondary winding is connected to the second ends of the other N inductor branches 31 (N+1), 31 (N+2), ... 31 (2N); the first end of each inductor branch 311, 312, ... 31 (2N) is connected to the midpoint of one of the diode branches 321, 322, ... 32 (2N) in a one-to-one correspondence.
[0049] Figure 7 : is a circuit diagram of another preferred embodiment of the DCDC circuit of the utility model with rectifier diodes connected in parallel and current sharing, which is Figure 5 The illustrated embodiments are similar, except that the DCDC circuit is a full-bridge or phase-shifted full-bridge circuit. Figure 8 : is a circuit diagram of another preferred embodiment of the DCDC circuit of the utility model with rectifier diodes connected in parallel and current sharing, which is Figure 6 The embodiment shown is similar, except that the DCDC circuit is a full bridge or a phase-shifted full bridge circuit. Based on the teachings of the above embodiments, its principle and structure are obvious to those skilled in the art, and will not be described again.
[0050] The DCDC circuit for current equalization by connecting rectifier diodes in parallel of the utility model is cleverly implemented by adding an inductor branch between each diode branch and the connection end of the transformer, thereby reducing the voltage difference between the two series diodes in each diode branch, thereby achieving a good current equalization effect, which is beneficial to the power improvement of the DCDC circuit. The entire circuit structure is simple and easy to implement, and the device cost is low, and it is easy to promote and apply. In addition, the DCDC circuit for current equalization by connecting rectifier diodes in parallel of the utility model is suitable for various DCDC circuits, such as LLC topology, full bridge or phase-shifted full bridge topology, and has a wide range of application scenarios. Furthermore, the inductor branch can be realized by an independent inductor, PCB trace inductance or transformer leakage inductance, so the circuit is simple and reliable.
[0051] The utility model aims to solve the problem that the negative temperature coefficient of the conduction voltage drop of the fast recovery diode leads to the inability to balance the current when used in parallel. A series inductor is added to the diode branch to increase the impedance of the branch. The higher the frequency and the greater the inductance, the better the current balance. The inductor can be an independent inductor, a PCB trace inductor, a transformer leakage inductor, etc. It is simple and reliable, and can realize the parallel use of two to N fast recovery diodes, which is beneficial to the module to increase the power.
[0052] Although the present invention is described through specific embodiments, it should be understood by those skilled in the art that various changes and equivalent substitutions may be made to the present invention without departing from the scope of the present invention. In addition, various modifications may be made to the present invention for specific situations or materials without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed, but should include all implementation methods that fall within the scope of the claims of the present invention.
[0053] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A DCDC circuit with parallel-connected rectifier diodes for current sharing, comprising: A transformer module, a primary input module arranged on the primary side of the transformer module, and a secondary output module arranged on the secondary side of the transformer module; characterized in that the secondary output module includes 2N diode branches, 2N inductor branches and an output unit; the 2N diode branches are connected in parallel at both ends of the output unit; each of the diode branches includes two diodes connected in series; the first end of each of the inductor branches is connected to the midpoint of a diode branch one by one, and the second end is connected to the secondary winding of the transformer module; wherein N is a positive integer.
2. The DCDC circuit with parallel rectifier diodes and current sharing according to claim 1, characterized in that: The inductor branch includes at least one inductor, and the diode includes a fast recovery diode, a Schottky diode and a SIC diode.
3. The DCDC circuit with parallel rectifier diodes and current sharing according to claim 2, characterized in that: The inductor is an independent inductor, a lead inductor or a leakage inductor of the transformer module.
4. The DCDC circuit with parallel rectifier diodes and current sharing according to any one of claims 1 to 3, characterized in that: The transformer module includes a secondary winding, a first end of the secondary winding is connected to the second ends of N inductor branches; a second end of the secondary winding is connected to the second ends of another N inductor branches; and a first end of each inductor branch is connected to a midpoint of a diode branch one by one.
5. The DCDC circuit with parallel rectifier diodes and current sharing according to any one of claims 1 to 3, characterized in that: The transformer module includes N secondary windings, each secondary winding includes a first end and a second end; 2N ends of the N secondary windings are connected to the second ends of 2N inductor branches in a one-to-one correspondence; and the first end of each inductor branch is connected to the midpoint of a diode branch in a one-to-one correspondence.
6. The DCDC circuit with parallel connected rectifier diodes for current sharing according to any one of claims 1 to 3, characterized in that: The output unit includes an output capacitor.
7. The DCDC circuit with parallel rectifier diodes for current sharing according to claim 6, characterized in that: The output unit includes an output capacitor and an output inductor connected in series.
8. The DCDC circuit with parallel connected rectifier diodes for current sharing according to any one of claims 1 to 3, characterized in that: The primary input module includes an input capacitor, a first switch tube, a second switch tube, a third switch tube and a fourth switch tube; the control ends of the first switch tube, the second switch tube, the third switch tube and the fourth switch tube receive a control signal, the first end of the first switch tube is connected to the second end of the second switch tube, and the second end is connected to the second end of the third switch tube and the first end of the input capacitor, the first end of the second switch tube is connected to the first end of the fourth switch tube and the second end of the input capacitor, and the first end of the third switch tube is connected to the second end of the fourth switch tube.
9. The DCDC circuit with parallel rectifier diodes and current sharing according to claim 8, characterized in that: The primary input module further includes a resonant capacitor and a resonant inductor; The first end of the resonant capacitor is connected to the first end of the primary winding of the transformer module, and the second end is connected to the first end of the first switch tube and the second end of the second switch tube via the resonant inductor; the second end of the primary winding of the transformer module is connected to the first end of the third switch tube and the second end of the fourth switch tube.
10. The DCDC circuit with parallel rectifier diodes and current sharing according to claim 8, characterized in that: The primary input module further includes a resonant capacitor and a resonant inductor; The first end of the resonant inductor is connected to the first end of the primary winding of the transformer module, and the second end is connected to the first end of the first switch tube and the second end of the second switch tube via the resonant capacitor; the second end of the primary winding of the transformer module is connected to the first end of the third switch tube and the second end of the fourth switch tube.