Secondary side voltage-sharing three-phase LLC circuit

Abstract

According to the secondary-side voltage-sharing three-phase LLC circuit, a first secondary-side voltage-sharing module is arranged between two ends of a first output capacitor module and a second rectification module, and / or a second secondary-side voltage-sharing module is arranged between two ends of a second output capacitor module and a first rectification module. When the voltage of the second transformer module or the first transformer module is high, energy is transmitted to the first output capacitor module and / or the second output capacitor module through the first secondary side voltage-sharing module and / or the second secondary side voltage-sharing module. Therefore, voltage sharing of the first output capacitor module and the second output capacitor module is realized, and device damage is prevented. Furthermore, according to the secondary side voltage-sharing three-phase LLC circuit provided by the utility model, an existing three-phase LLC circuit does not need to be greatly adjusted or changed, so that low-cost manufacturing and implementation are facilitated.

Description

Technical Field

[0001] The utility model relates to a power supply module, and more specifically to a secondary side voltage-equalizing three-phase LLC circuit. Background Art

[0002] As the country vigorously promotes carbon neutrality, new energy vehicles, especially electric vehicles, have achieved unprecedented development in recent years. In order to meet the charging needs of electric vehicles, charging piles have increasing requirements for the power and reliability of charging modules. Existing charging modules usually adopt three-phase LLC topology circuits. However, the existing three-phase LLC circuits usually only consider the voltage balancing problem between LLC circuits, but do not consider the voltage balancing problem at both ends of the secondary output capacitor. For the existing three-phase LLC circuit, when full-wave rectification is used on the secondary side, due to the difference in magnetic parameters, the output capacitor is not voltage-balanced, and the reliability of some devices is affected. Utility Model Content

[0003] The technical problem to be solved by the present invention is to provide a secondary-side voltage-equalizing three-phase LLC circuit for the above-mentioned defects of the prior art, which can solve the above-mentioned voltage-equalizing problem.

[0004] The technical solution adopted by the utility model to solve the technical problem is: construct a secondary side voltage equalization three-phase LLC circuit, including a first primary side input module, a first transformer module, a first rectifier module, and a first output capacitor module connected in sequence, and a second primary side input module, a second transformer module, a second rectifier module, and a second output capacitor module connected in sequence;

[0005] The input ends of the first primary input module and the second primary input module are respectively connected in parallel to the two ends of the input voltage, and the output ends are respectively connected to the primary sides of the first transformer module and the second transformer module; the secondary sides of the first transformer module and the second transformer module are respectively connected to the first output capacitor module and the second output capacitor module via the first rectifier module and the second rectifier module; the first rectifier module is connected to the first output capacitor module, and the second rectifier module is connected to the second output capacitor module;

[0006] The secondary side voltage equalization three-phase LLC circuit further comprises a first secondary side voltage equalization module and / or a second secondary side voltage equalization module;

[0007] The first end of the first secondary voltage equalizing module is connected to the first rectifier module and the first output capacitor module, the second end is connected to the connection point of the first output capacitor module and the second output capacitor module, and the third end is connected to the second rectifier module and the second transformer module;

[0008] The first end of the second secondary voltage equalizing module is connected to the connection point of the first output capacitor module and the second output capacitor module, the second end is connected to the second rectifier module and the second output capacitor module, and the third end is connected to the first rectifier module and the first transformer module.

[0009] In the secondary side voltage equalization three-phase LLC circuit described in the utility model, the first secondary side voltage equalization module includes a first secondary side voltage equalization network; the first end of the first secondary side voltage equalization network is connected to the first end of the first output capacitor module, the second end is connected to the second end of the first output capacitor module and the first end of the second output capacitor module, and the third end is connected to the input end of the second rectifier module and the secondary side of the second transformer;

[0010] The second secondary side voltage equalizing module includes a second secondary side voltage equalizing network; the first end of the second secondary side voltage equalizing network is connected to the second end of the first output capacitor module and the first end of the second output capacitor module, the second end is connected to the second end of the second output capacitor module, and the third end is connected to the input end of the first rectifier module and the secondary side of the first transformer module.

[0011] In the secondary-side voltage equalization three-phase LLC circuit described in the utility model, the secondary-side voltage equalization network respectively includes a first voltage equalization diode, a second voltage equalization diode, a voltage equalization capacitor and a voltage equalization inductor, the cathode of the first voltage equalization diode is connected to the first end of the secondary-side voltage equalization network, and the anode is connected to the cathode of the second voltage equalization diode and the first end of the voltage equalization capacitor, the anode of the second voltage equalization diode is connected to the second end of the secondary-side voltage equalization network, the second end of the voltage equalization capacitor is connected to the first end of the voltage equalization inductor, and the second end of the voltage equalization inductor is connected to the third end of the secondary-side voltage equalization network.

[0012] In the secondary-side voltage-balanced three-phase LLC circuit described in the present invention, the first output capacitor module includes a first capacitor, the second output capacitor module includes a second capacitor, and the first capacitor and the second capacitor are connected in series.

[0013] In the secondary side voltage-balanced three-phase LLC circuit described in the utility model, the first transformer module includes a first transformer, a second transformer and a third transformer;

[0014] The first rectifier module includes a first rectifier diode, a second rectifier diode, a third rectifier diode, a fourth rectifier diode, a fifth rectifier diode and a sixth rectifier diode;

[0015] The first end of the secondary winding of the first transformer is connected to the anode of the first rectifier diode, the second end of the secondary winding of the first transformer is connected to the anode of the second rectifier diode, the first end of the secondary winding of the second transformer is connected to the anode of the third rectifier diode, the second end of the secondary winding of the second transformer is connected to the anode of the fourth rectifier diode, the first end of the secondary winding of the third transformer is connected to the anode of the fifth rectifier diode, and the second end of the secondary winding of the third transformer is connected to the anode of the sixth rectifier diode; the third end of the secondary winding of the first transformer, the third end of the secondary winding of the second transformer and the third end of the secondary winding of the third transformer are all connected to the second end of the first capacitor and the first end of the second capacitor;

[0016] The cathodes of the first rectifier diode, the second rectifier diode, the third rectifier diode, the fourth rectifier diode, the fifth rectifier diode and the sixth rectifier diode are all connected to the first end of the first capacitor.

[0017] In the secondary side voltage-balanced three-phase LLC circuit described in the utility model, the second transformer module includes a fourth transformer, a fifth transformer and a sixth transformer;

[0018] The second rectifier module includes a seventh rectifier diode, an eighth rectifier diode, a ninth rectifier diode, a tenth rectifier diode, an eleventh rectifier diode and a twelfth rectifier diode;

[0019] The first end of the secondary winding of the fourth transformer is connected to the anode of the seventh rectifier diode, the second end of the secondary winding of the fourth transformer is connected to the anode of the eighth rectifier diode, the first end of the secondary winding of the fifth transformer is connected to the anode of the ninth rectifier diode, the second end of the secondary winding of the fifth transformer is connected to the anode of the tenth rectifier diode, the first end of the secondary winding of the sixth transformer is connected to the anode of the eleventh rectifier diode, and the second end of the secondary winding of the sixth transformer is connected to the anode of the twelfth rectifier diode; the third end of the secondary winding of the fourth transformer, the third end of the secondary winding of the fifth transformer and the third end of the secondary winding of the sixth transformer are all connected to the second end of the second capacitor;

[0020] The cathodes of the seventh rectifier diode, the eighth rectifier diode, the ninth rectifier diode, the tenth rectifier diode, the eleventh rectifier diode and the twelfth rectifier diode are all connected to the first end of the second capacitor and the second end of the first capacitor.

[0021] In the secondary side voltage balancing three-phase LLC circuit described in the utility model, the first secondary side voltage balancing module includes six first secondary side voltage balancing networks;

[0022] The first end of each of the first secondary side voltage equalizing networks is connected to the first end of the first capacitor, the second end is connected to the second end of the first capacitor and the first end of the second capacitor, and the third end is respectively connected to the anode of the seventh rectifier diode, the anode of the eighth rectifier diode, the anode of the ninth rectifier diode, the anode of the tenth rectifier diode, the anode of the eleventh rectifier diode or the anode of the twelfth rectifier diode.

[0023] In the secondary side voltage balancing three-phase LLC circuit described in the utility model, the second secondary side voltage balancing module includes six second secondary side voltage balancing networks;

[0024] The first end of each second secondary side voltage equalizing network is connected to the second end of the first capacitor and the first end of the second capacitor, the second end is connected to the second end of the second capacitor, and the third end is respectively connected to the anode of the first rectifier diode, the anode of the second rectifier diode, the anode of the third rectifier diode, the anode of the fourth rectifier diode, the anode of the fifth rectifier diode or the anode of the sixth rectifier diode.

[0025] In the secondary voltage-balanced three-phase LLC circuit described in the utility model, the first end of the primary winding of the first transformer, the first end of the primary winding of the second transformer, and the first end of the primary winding of the third transformer are respectively connected to the first primary input module;

[0026] The first end of the primary winding of the fourth transformer, the first end of the primary winding of the fifth transformer and the first end of the primary winding of the sixth transformer are respectively connected to the second primary input module;

[0027] The second end of the primary winding of the first transformer is connected to the second end of the primary winding of the fourth transformer, the second end of the primary winding of the second transformer is connected to the second end of the primary winding of the fifth transformer, and the second end of the primary winding of the third transformer is connected to the second end of the primary winding of the sixth transformer.

[0028] In the secondary-side voltage-balanced three-phase LLC circuit described in the present invention, the first primary-side input module and the second primary-side input module respectively include a switch tube network.

[0029] In implementing the secondary-side voltage-equalizing three-phase LLC circuit of the utility model, by setting a first secondary-side voltage-equalizing module between the two ends of the first output capacitor module and the second rectifier module, and / or setting a second secondary-side voltage-equalizing module between the two ends of the second output capacitor module and the first rectifier module, when the voltage of the second transformer module or the first transformer module is high, energy can be transferred to the first output capacitor module and / or the second output capacitor module through the first secondary-side voltage-equalizing module and / or the second secondary-side voltage-equalizing module, respectively, so as to achieve voltage equalization of the first output capacitor module and the second output capacitor module, thereby preventing device damage. Furthermore, the secondary-side voltage-equalizing three-phase LLC circuit of the utility model does not require excessive adjustments or changes to the existing three-phase LLC circuit, and is therefore easy to manufacture and implement at low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0031] Figure 1 It is a principle block diagram of a preferred embodiment of a secondary side voltage-equalizing three-phase LLC circuit of the utility model;

[0032] Figure 2 It is a principle block diagram of another preferred embodiment of the secondary side voltage-balanced three-phase LLC circuit of the utility model;

[0033] Figure 3 It is a principle block diagram of another preferred embodiment of the secondary side voltage equalization three-phase LLC circuit of the utility model;

[0034] Figure 4 It is a circuit diagram of another preferred embodiment of the secondary side voltage equalization three-phase LLC circuit of the utility model. DETAILED DESCRIPTION

[0035] 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.

[0036] In a three-phase LLC circuit, under the condition of high-power application, multiple LLC circuits need to be staggered in parallel to increase the output power and reduce the output ripple. However, the LLC circuit is affected by the resonance parameter deviation, and there will be certain problems of uneven current or uneven voltage between different LLC circuits. Therefore, the circuits in the prior art often focus on the voltage or current equalization problems between different LLC circuits, and basically ignore the voltage equalization problem at both ends of the secondary output capacitor. The problem of uneven voltage at both ends of the secondary output capacitor will occur due to the difference in magnetic component parameters when full-wave rectification is adopted on the secondary side, thereby affecting the reliability of some devices. It was only during a long period of experiment that the inventor discovered that the cause of these problems was the uneven voltage problem at both ends of the secondary output capacitor, and then found a solution. Therefore, the discovery of the technical problem of the present application itself is also creative.

[0037] Figure 1 1 is a principle block diagram of a preferred embodiment of a secondary voltage-balanced three-phase LLC circuit of the present utility model. Figure 1 As shown, the secondary side voltage equalization three-phase LLC circuit includes a first primary input module 110, a first transformer module 210, a first rectifier module 310, and a first output capacitor module 510 connected in sequence, and a second primary input module 120, a second transformer module 220, a second rectifier module 320, and a second output capacitor module 520 connected in sequence.

[0038] like Figure 1 As shown, the input ends of the first primary input module 110 and the second primary input module 120 are respectively connected in parallel to the two ends of the input voltage, and the output ends are respectively connected to the primary sides of the first transformer module 210 and the second transformer module 220; the secondary sides of the first transformer module 210 and the second transformer module 220 are respectively connected to the first output capacitor module 510 and the second output capacitor module 520 via the first rectifier module 310 and the second rectifier module 320. The primary sides of the first transformer module 210 and the second transformer module 220 are staggered; the first rectifier module 310 is connected to the first output capacitor module 510, and the second rectifier module 320 is connected to the second output capacitor module 520.

[0039] exist Figure 1 In the preferred embodiment shown, the secondary side voltage equalizing three-phase LLC circuit further includes a first secondary side voltage equalizing module 410; the first end of the first secondary side voltage equalizing module 410 is connected to the first rectifier module 310 and the first output capacitor module 510, the second end is connected to the connection point of the first output capacitor module 510 and the second output capacitor module 520, and the third end is connected to the second rectifier module 320 and the second transformer module 220.

[0040] Figure 2 It is a principle block diagram of another preferred embodiment of the secondary side voltage equalization three-phase LLC circuit of the utility model. Figure 2 The embodiment shown is Figure 1 The embodiment shown is similar, with the difference that the secondary side voltage equalization three-phase LLC circuit further includes a second secondary side voltage equalization module 420; the first end of the second secondary side voltage equalization module 420 is connected to the connection point of the first output capacitor module 510 and the second output capacitor module 520, the second end is connected to the second rectifier module 320 and the second output capacitor module 520, and the third end is connected to the first rectifier module 310 and the first transformer module 210.

[0041] Figure 3 It is a principle block diagram of another preferred embodiment of the secondary side voltage equalization three-phase LLC circuit of the utility model. Figure 3 The embodiment shown is Figure 1 The embodiment shown is similar, with the difference that the secondary side voltage equalizing three-phase LLC circuit further includes a first secondary side voltage equalizing module 410 and a second secondary side voltage equalizing module 420 at the same time; the first end of the second secondary side voltage equalizing module 420 is connected to the connection point of the first output capacitor module 510 and the second output capacitor module 520, the second end is connected to the second rectifier module 320 and the second output capacitor module 520, and the third end is connected to the first rectifier module 310 and the secondary side of the first transformer module 210.

[0042] In a preferred embodiment of the present invention, the first primary input module 110, the first transformer module 210, the first rectifier module 310, the first output capacitor module 510, the second primary input module 120, the second transformer module 220, the second rectifier module 320, and the second output capacitor module 520 can be constructed using any corresponding modules or devices known in the art.

[0043] The first secondary voltage equalizing module 410 and the second secondary voltage equalizing module 420 can be constructed using any known resonant module. In a preferred embodiment of the present utility model, the first secondary voltage equalizing module 410 and the second secondary voltage equalizing module 420 respectively include at least one secondary voltage equalizing network. For example, the first secondary voltage equalizing module 410 includes a first secondary voltage equalizing network; the first end of the first secondary voltage equalizing network is connected to the first end of the first output capacitor module 510, the second end is connected to the second end of the first output capacitor module 510 and the first end of the second output capacitor module 520, and the third end is connected to the input end of the second rectifier module 320 and the secondary side of the second transformer module 220.

[0044] For another example, the second secondary side voltage equalizing module 420 includes a second secondary side voltage equalizing network; the first end of the second secondary side voltage equalizing network is connected to the second end of the first output capacitor module 510 and the first end of the second output capacitor module 520, the second end is connected to the second end of the second output capacitor module 520, and the third end is connected to the input end of the first rectifier module 310.

[0045] In a preferred embodiment of the utility model, the secondary voltage equalizing network respectively includes a first voltage equalizing diode, a second voltage equalizing diode, a voltage equalizing capacitor and a voltage equalizing inductor, the cathode of the first voltage equalizing diode is connected to the first end of the secondary voltage equalizing network, and the anode is connected to the cathode of the second voltage equalizing diode and the first end of the voltage equalizing capacitor, the anode of the second voltage equalizing diode is connected to the second end of the secondary voltage equalizing network, the second end of the voltage equalizing capacitor is connected to the first end of the voltage equalizing inductor, and the second end of the voltage equalizing inductor is connected to the third end of the secondary voltage equalizing network.

[0046] In the present invention, by setting a first secondary side voltage equalizing module 410 between the two ends of the first output capacitor module 510 and between the second rectifier module 320, and / or setting a second secondary side voltage equalizing module 420 between the two ends of the second output capacitor module 520 and between the first rectifier module 310, when the voltage of the second transformer module or the first transformer module is higher, energy can be transferred to the first output capacitor module 510 and / or the second output capacitor module 520 through the first secondary side voltage equalizing module 410 and / or the second secondary side voltage equalizing module 420, respectively, thereby achieving voltage equalization of the first output capacitor module 510 and the second output capacitor module 520.

[0047] Figure 4 FIG. 2 is a circuit diagram of another preferred embodiment of the secondary side voltage equalization three-phase LLC circuit of the utility model. Figure 4 As shown, the secondary side voltage equalization three-phase LLC circuit of the present utility model comprises a first primary input module 110, a first transformer module 210, a first rectifier module 310, and a first output capacitor module 510 connected in sequence, and a second primary input module 120, a second transformer module 220, a second rectifier module 320, a second output capacitor module 520 connected in sequence, and a first secondary side voltage equalization module 410 and a second secondary side voltage equalization module 420. The first end of the second secondary side voltage equalization module 420 is connected to the connection point of the first output capacitor module 510 and the second output capacitor module 520, the second end is connected to the second rectifier module 320 and the second output capacitor module 520, and the third end is connected to the first rectifier module 310.

[0048] Further Figure 4As shown, the first primary input module 110 and the second primary input module 120 respectively include a switch tube network composed of six switch tubes, whose input ends are respectively connected in parallel to the two ends of the input voltage, and the output ends are respectively connected to the first transformer module 210 and the second transformer module 220.

[0049] The first transformer module 210 includes a transformer T1, a transformer T2, and a transformer T3; the second transformer module 220 includes a transformer T4, a transformer T5, and a transformer T6. The first rectifier module 310 includes a rectifier diode D41, a rectifier diode D42, a rectifier diode D43, a rectifier diode D44, a rectifier diode D45, and a rectifier diode D46. The second rectifier module 320 includes a rectifier diode D47, a rectifier diode D48, a rectifier diode D49, a rectifier diode D50, a rectifier diode D51, and a rectifier diode D52.

[0050] The first secondary side voltage equalizing module 410 includes six first secondary side voltage equalizing networks, namely, a first secondary side voltage equalizing network composed of a voltage equalizing diode D10, a voltage equalizing diode D11, a voltage equalizing capacitor C10 and a voltage equalizing inductor L10; a first secondary side voltage equalizing network composed of a voltage equalizing diode D12, a voltage equalizing diode D13, a voltage equalizing capacitor C11 and a voltage equalizing inductor L11; a first secondary side voltage equalizing network composed of a voltage equalizing diode D14, a voltage equalizing diode D15, a voltage equalizing capacitor C12 and a voltage equalizing inductor L12; a first secondary side voltage equalizing network composed of a voltage equalizing diode D16, a voltage equalizing diode D17, a voltage equalizing capacitor C13 and a voltage equalizing inductor L13; a first secondary side voltage equalizing network composed of a voltage equalizing diode D18, a voltage equalizing diode D19, a voltage equalizing capacitor C14 and a voltage equalizing inductor L14; a first secondary side voltage equalizing network composed of a voltage equalizing diode D20, a voltage equalizing diode D21, a voltage equalizing capacitor C12 and a voltage equalizing inductor L15.

[0051] The second secondary side voltage equalizing module 420 includes six second secondary side voltage equalizing networks, namely, a second secondary side voltage equalizing network composed of a voltage equalizing diode D22, a voltage equalizing diode D23, a voltage equalizing capacitor C16 and a voltage equalizing inductor L16; a second secondary side voltage equalizing network composed of a voltage equalizing diode D24, a voltage equalizing diode D25, a voltage equalizing capacitor C17 and a voltage equalizing inductor L17; a second secondary side voltage equalizing network composed of a voltage equalizing diode D26, a voltage equalizing diode D27, a voltage equalizing capacitor C18 and a voltage equalizing inductor L18; a second secondary side voltage equalizing network composed of a voltage equalizing diode D28, a voltage equalizing diode D29, a voltage equalizing capacitor C19 and a voltage equalizing inductor L19; a second secondary side voltage equalizing network composed of a voltage equalizing diode D30, a voltage equalizing diode D31, a voltage equalizing capacitor C20 and a voltage equalizing inductor L20; a second secondary side voltage equalizing network composed of a voltage equalizing diode D32, a voltage equalizing diode D33, a voltage equalizing capacitor C21 and a voltage equalizing inductor L21.

[0052] The first output capacitor module 510 includes a capacitor C11, and the second output capacitor module 520 includes a capacitor C12. The capacitor C11 and the capacitor C12 are connected in series.

[0053] like Figure 4 As shown, the first end of the primary winding of the transformer T1, the first end of the primary winding of the transformer T2 and the first end of the primary winding of the transformer T3 are respectively connected to the first primary input module 110; the first end of the primary winding of the transformer T4, the first end of the primary winding of the transformer T5 and the first end of the primary winding of the transformer T6 are respectively connected to the second primary input module 120; the second end of the primary winding of the transformer T1 is connected to the second end of the primary winding of the transformer T4, the second end of the primary winding of the transformer T2 is connected to the second end of the primary winding of the transformer T5, and the second end of the primary winding of the transformer T3 is connected to the second end of the primary winding of the transformer T6.

[0054] The first end of the secondary winding of the transformer T1 is connected to the anode of the rectifier diode D41, the second end of the secondary winding of the transformer T1 is connected to the anode of the rectifier diode D42, the first end of the secondary winding of the transformer T2 is connected to the anode of the rectifier diode D43, the second end of the secondary winding of the transformer T2 is connected to the anode of the rectifier diode D44, the first end of the secondary winding of the transformer T3 is connected to the anode of the rectifier diode D45, and the second end of the secondary winding of the transformer T3 is connected to the anode of the rectifier diode D46; the third end of the secondary winding of the transformer T1, the third end of the secondary winding of the transformer T2 and the third end of the secondary winding of the transformer T3 are all connected to the second end of the capacitor C11 and the first end of the capacitor C12. The cathodes of the rectifier diodes D41, D42, D43, D44, D45 and D46 are all connected to the first end of the capacitor C11.

[0055] The first end of the secondary winding of the transformer T4 is connected to the anode of the rectifier diode D47, the second end of the secondary winding of the transformer T4 is connected to the anode of the rectifier diode D48, the first end of the secondary winding of the transformer T5 is connected to the anode of the rectifier diode D49, the second end of the secondary winding of the transformer T5 is connected to the anode of the rectifier diode D50, the first end of the secondary winding of the transformer T6 is connected to the anode of the rectifier diode D51, and the second end of the secondary winding of the transformer T6 is connected to the anode of the rectifier diode D52; the third end of the secondary winding of the transformer T4, the third end of the secondary winding of the transformer T5 and the third end of the secondary winding of the transformer T6 are all connected to the second end of the capacitor C12; the cathodes of the rectifier diode D47, the rectifier diode D48, the rectifier diode D49, the rectifier diode D50, the rectifier diode D51 and the rectifier diode D52 are all connected to the first end of the capacitor C12 and the second end of the capacitor C11.

[0056] The first end of the first secondary voltage equalization network composed of voltage equalization diode D10, voltage equalization diode D11, voltage equalization capacitor C10 and voltage equalization inductor L10 is connected to the first end of the capacitor C11, the second end is connected to the second end of the capacitor C11 and the first end of the capacitor C12, and the third end is connected to the anode of the rectifier diode D47. The first end of the first secondary voltage equalization network composed of voltage equalization diode D12, voltage equalization diode D13, voltage equalization capacitor C11 and voltage equalization inductor L11 is connected to the first end of the capacitor C11, the second end is connected to the second end of the capacitor C11 and the first end of the capacitor C12, and the third end is connected to the anode of the rectifier diode D48. The first end of the first secondary voltage equalization network composed of voltage equalization diode D14, voltage equalization diode D15, voltage equalization capacitor C12 and voltage equalization inductor L12 is connected to the first end of the capacitor C11, the second end is connected to the second end of the capacitor C11 and the first end of the capacitor C12, and the third end is connected to the anode of the rectifier diode D49. The first end of the first secondary voltage equalization network composed of voltage equalization diode D16, voltage equalization diode D17, voltage equalization capacitor C13 and voltage equalization inductor L13 is connected to the first end of the capacitor C11, the second end is connected to the second end of the capacitor C11 and the first end of the capacitor C12, and the third end is connected to the anode of the rectifier diode D50. The first end of the first secondary voltage equalization network composed of voltage equalization diode D18, voltage equalization diode D19, voltage equalization capacitor C14 and voltage equalization inductor L14 is connected to the first end of the capacitor C11, the second end is connected to the second end of the capacitor C11 and the first end of the capacitor C12, and the third end is connected to the anode of the rectifier diode D51. The first end of the first secondary voltage equalization network composed of voltage equalization diode D20, voltage equalization diode D21, voltage equalization capacitor C12 and voltage equalization inductor L15 is connected to the first end of the capacitor C11, the second end is connected to the second end of the capacitor C11 and the first end of the capacitor C12, and the third end is connected to the anode of the rectifier diode D52.

[0057] Similarly, for the second secondary side voltage equalizing network composed of voltage equalizing diode D22, voltage equalizing diode D23, voltage equalizing capacitor C16 and voltage equalizing inductor L16; the second secondary side voltage equalizing network composed of voltage equalizing diode D24, voltage equalizing diode D25, voltage equalizing capacitor C17 and voltage equalizing inductor L17; the second secondary side voltage equalizing network composed of voltage equalizing diode D26, voltage equalizing diode D27, voltage equalizing capacitor C18 and voltage equalizing inductor L18; the second secondary side voltage equalizing network composed of voltage equalizing diode D28, voltage equalizing diode D29, voltage equalizing capacitor C19 and voltage equalizing inductor L19; the second secondary side voltage equalizing network composed of voltage equalizing diode D30, voltage equalizing diode D31, voltage equalizing capacitor C20 and voltage equalizing inductor L32; a second secondary side voltage equalizing network composed of a piezo-inductor L20; a second secondary side voltage equalizing network composed of a voltage equalizing diode D32, a voltage equalizing diode D33, a voltage equalizing capacitor C21 and a voltage equalizing inductor L21; a first end of each of the second secondary side voltage equalizing networks is connected to the second end of the capacitor C11 and the first end of the capacitor C12, a second end is connected to the second end of the capacitor C12, and a third end is respectively connected to the anode of the rectifier diode D41, the anode of the rectifier diode D42, the anode of the rectifier diode D43, the anode of the rectifier diode D44, the anode of the rectifier diode D45 or the anode of the rectifier diode D46.

[0058] exist Figure 4 In the preferred embodiment shown, the first secondary side voltage balancing module 410 and the second secondary side voltage balancing module 420 are provided at the same time, and the first secondary side voltage balancing module 410 includes six first secondary side voltage balancing networks, and the second secondary side voltage balancing module 420 includes six second secondary side voltage balancing networks. However, those skilled in the art know that in actual situations, Figure 1-2 As in the embodiment shown, only the first secondary side voltage equalizing module 410 or the second secondary side voltage equalizing module 420 is provided, and the first secondary side voltage equalizing module 410 and the second secondary side voltage equalizing module 420 can respectively include one secondary side voltage equalizing network, or two secondary side voltage equalizing networks, or other number of secondary side voltage equalizing networks. Figure 4 As shown, twelve secondary side voltage equalizing networks are included.

[0059] In other preferred embodiments of the present invention, the first rectifier module 310 and the second rectifier module 320 may also adopt any other suitable rectifier modules, such as a switch tube rectifier module, a full-bridge rectifier module, etc., which all fall within the protection scope of the present invention.

[0060] like Figure 4As shown, the secondary side voltage equalization three-phase LL capacitor C circuit of the utility model has diodes D10-D21 connected in parallel at both ends of capacitor C1, and diodes D22-D33 connected in parallel at both ends of capacitor C2. When the voltage of transformer T4 winding is high, part of the winding energy can be transferred to capacitor C1 through a secondary side voltage equalization network composed of voltage equalization capacitor C10, voltage equalization inductor L10, voltage equalization diode D10, and voltage equalization diode D11, thereby playing the role of capacitor C1 / capacitor C2 voltage equalization. Similarly, 12 secondary side voltage equalization networks as described above can be constructed to better play the role of capacitor C1 and capacitor C2 voltage equalization.

[0061] Implementing the secondary side voltage equalization three-phase LLC circuit of the utility model, in the utility model, by setting a first secondary side voltage equalization module between the two ends of the first output capacitor module and the second rectifier module, and / or setting a second secondary side voltage equalization module between the two ends of the second output capacitor module and the first rectifier module, when the voltage of the second transformer module or the first transformer module is higher, energy can be transferred to the first output capacitor module and / or the second output capacitor module through the first secondary side voltage equalization module and / or the second secondary side voltage equalization module, respectively, so as to realize voltage equalization of the first output capacitor module and the second output capacitor module, thereby preventing device damage. Furthermore, the secondary side voltage equalization three-phase LLC circuit of the utility model does not require excessive adjustment or change to the existing three-phase LLC circuit, and is therefore easy to manufacture and implement at low cost.

[0062] 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.

[0063] 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 three-phase LLC circuit with secondary voltage equalization, characterized in that: It includes a first primary input module, a first transformer module, a first rectifier module, and a first output capacitor module connected in sequence, and a second primary input module, a second transformer module, a second rectifier module, and a second output capacitor module connected in sequence; The input ends of the first primary input module and the second primary input module are respectively connected in parallel to the two ends of the input voltage, and the output ends are respectively connected to the primary sides of the first transformer module and the second transformer module; the secondary sides of the first transformer module and the second transformer module are respectively connected to the first output capacitor module and the second output capacitor module via the first rectifier module and the second rectifier module; the first rectifier module is connected to the first output capacitor module, and the second rectifier module is connected to the second output capacitor module; The secondary side voltage equalization three-phase LLC circuit further comprises a first secondary side voltage equalization module and / or a second secondary side voltage equalization module; The first end of the first secondary voltage equalizing module is connected to the first rectifier module and the first output capacitor module, the second end is connected to the connection point of the first output capacitor module and the second output capacitor module, and the third end is connected to the second rectifier module and the second transformer module; The first end of the second secondary voltage equalizing module is connected to the connection point of the first output capacitor module and the second output capacitor module, the second end is connected to the second rectifier module and the second output capacitor module, and the third end is connected to the first rectifier module and the first transformer module.

2. The secondary side voltage-balanced three-phase LLC circuit according to claim 1, characterized in that: The first secondary voltage balancing module includes a first secondary voltage balancing network; a first end of the first secondary voltage balancing network is connected to a first end of the first output capacitor module, a second end is connected to a second end of the first output capacitor module and a first end of the second output capacitor module, and a third end is connected to an input end of the second rectifier module and a secondary side of the second transformer module; The second secondary side voltage equalizing module includes a second secondary side voltage equalizing network; the first end of the second secondary side voltage equalizing network is connected to the second end of the first output capacitor module and the first end of the second output capacitor module, the second end is connected to the second end of the second output capacitor module, and the third end is connected to the input end of the first rectifier module and the secondary side of the first transformer module.

3. The secondary side voltage-balanced three-phase LLC circuit according to claim 2, characterized in that: The secondary voltage equalizing network includes a first voltage equalizing diode, a second voltage equalizing diode, a voltage equalizing capacitor and a voltage equalizing inductor, wherein the cathode of the first voltage equalizing diode is connected to the first end of the secondary voltage equalizing network, and the anode is connected to the cathode of the second voltage equalizing diode and the first end of the voltage equalizing capacitor, the anode of the second voltage equalizing diode is connected to the second end of the secondary voltage equalizing network, the second end of the voltage equalizing capacitor is connected to the first end of the voltage equalizing inductor, and the second end of the voltage equalizing inductor is connected to the third end of the secondary voltage equalizing network.

4. The secondary side voltage-balanced three-phase LLC circuit according to claim 3, characterized in that: The first output capacitor module includes a first capacitor, the second output capacitor module includes a second capacitor, and the first capacitor and the second capacitor are connected in series.

5. The secondary side voltage-balanced three-phase LLC circuit according to claim 4, characterized in that: The first transformer module includes a first transformer, a second transformer and a third transformer; The first rectifier module includes a first rectifier diode, a second rectifier diode, a third rectifier diode, a fourth rectifier diode, a fifth rectifier diode and a sixth rectifier diode; The first end of the secondary winding of the first transformer is connected to the anode of the first rectifier diode, the second end of the secondary winding of the first transformer is connected to the anode of the second rectifier diode, the first end of the secondary winding of the second transformer is connected to the anode of the third rectifier diode, the second end of the secondary winding of the second transformer is connected to the anode of the fourth rectifier diode, the first end of the secondary winding of the third transformer is connected to the anode of the fifth rectifier diode, and the second end of the secondary winding of the third transformer is connected to the anode of the sixth rectifier diode; the third end of the secondary winding of the first transformer, the third end of the secondary winding of the second transformer and the third end of the secondary winding of the third transformer are all connected to the second end of the first capacitor and the first end of the second capacitor; The cathodes of the first rectifier diode, the second rectifier diode, the third rectifier diode, the fourth rectifier diode, the fifth rectifier diode and the sixth rectifier diode are all connected to the first end of the first capacitor.

6. The secondary side voltage-balanced three-phase LLC circuit according to claim 5, characterized in that: The second transformer module includes a fourth transformer, a fifth transformer and a sixth transformer; The second rectifier module includes a seventh rectifier diode, an eighth rectifier diode, a ninth rectifier diode, a tenth rectifier diode, an eleventh rectifier diode and a twelfth rectifier diode; The first end of the secondary winding of the fourth transformer is connected to the anode of the seventh rectifier diode, the second end of the secondary winding of the fourth transformer is connected to the anode of the eighth rectifier diode, the first end of the secondary winding of the fifth transformer is connected to the anode of the ninth rectifier diode, the second end of the secondary winding of the fifth transformer is connected to the anode of the tenth rectifier diode, the first end of the secondary winding of the sixth transformer is connected to the anode of the eleventh rectifier diode, and the second end of the secondary winding of the sixth transformer is connected to the anode of the twelfth rectifier diode; the third end of the secondary winding of the fourth transformer, the third end of the secondary winding of the fifth transformer and the third end of the secondary winding of the sixth transformer are all connected to the second end of the second capacitor; The cathodes of the seventh rectifier diode, the eighth rectifier diode, the ninth rectifier diode, the tenth rectifier diode, the eleventh rectifier diode and the twelfth rectifier diode are all connected to the first end of the second capacitor and the second end of the first capacitor.

7. The secondary side voltage-balanced three-phase LLC circuit according to claim 6, characterized in that: The first secondary side voltage balancing module includes six first secondary side voltage balancing networks; The first end of each of the first secondary side voltage equalizing networks is connected to the first end of the first capacitor, the second end is connected to the second end of the first capacitor and the first end of the second capacitor, and the third end is respectively connected to the anode of the seventh rectifier diode, the anode of the eighth rectifier diode, the anode of the ninth rectifier diode, the anode of the tenth rectifier diode, the anode of the eleventh rectifier diode or the anode of the twelfth rectifier diode.

8. The secondary side voltage-balanced three-phase LLC circuit according to claim 6 or 7, characterized in that: The second secondary side voltage balancing module includes six second secondary side voltage balancing networks; The first end of each second secondary side voltage equalizing network is connected to the second end of the first capacitor and the first end of the second capacitor, the second end is connected to the second end of the second capacitor, and the third end is respectively connected to the anode of the first rectifier diode, the anode of the second rectifier diode, the anode of the third rectifier diode, the anode of the fourth rectifier diode, the anode of the fifth rectifier diode or the anode of the sixth rectifier diode.

9. The secondary side voltage-balanced three-phase LLC circuit according to claim 8, characterized in that: The first end of the primary winding of the first transformer, the first end of the primary winding of the second transformer and the first end of the primary winding of the third transformer are respectively connected to the first primary input module; The first end of the primary winding of the fourth transformer, the first end of the primary winding of the fifth transformer and the first end of the primary winding of the sixth transformer are respectively connected to the second primary input module; The second end of the primary winding of the first transformer is connected to the second end of the primary winding of the fourth transformer, the second end of the primary winding of the second transformer is connected to the second end of the primary winding of the fifth transformer, and the second end of the primary winding of the third transformer is connected to the second end of the primary winding of the sixth transformer.

10. The secondary side voltage-balanced three-phase LLC circuit according to claim 9, characterized in that: The first primary input module and the second primary input module respectively include a switch tube network.

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