Switching power supply device

Abstract

In the circuit element (10a), resonance circuits are connected in parallel. One end of the resonance capacitor (Crkq) of the q-th resonance circuit connected in parallel is connected in series with the resonance reactor (Lrq) and the primary winding (N1q) of the transformer (Trq). The other end of the resonance capacitor (Crkq) of the q-th resonance circuit that has been connected in parallel is connected to the resonance capacitor (Crkq) of the q-th resonance circuit that has been connected in parallel among the other circuit elements (10a) so that a k-dimensional multiphase LLC converter having a phase difference of 360 DEG / Pk is configured by means of Pk circuit elements.

Description

Technical Field

[0001] The present invention relates to a switching power supply device that converts an input voltage into an output voltage using a plurality of LLC converters connected in parallel. Background Art

[0002] In recent years, in order to achieve higher current and lower ripple as the output load increases, it is known that there is a multiphase switching power supply device that sets the number of operating phases (phase number) to multiple and drives each operating phase by staggering the phases (for example, refer to Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent No. 6696617 Summary of the invention

[0006] Problems to be solved by the invention

[0007] However, as the number of phases increases, the number of complementary gate drive signals of the complementary switches also increases. Therefore, the control becomes more complicated with the increase in the number of phases, and the circuits related to the control become larger in size, making it difficult to expand power based on multi-phase.

[0008] One aspect of the present invention provides a switching power supply device capable of increasing the power by connecting resonance circuits in parallel without increasing complementary gate drive signals.

[0009] Means for solving problems

[0010] A switching power supply device according to one embodiment of the present invention includes a plurality of half-bridge LLC converters in which resonance circuits are connected in parallel as circuit elements. The circuit element includes: a first switching element and a second switching element connected in series to both ends of a DC power supply; and m (m is a natural number greater than or equal to 2) resonance circuits connected in parallel, each including a resonance reactor having one end connected to a connection point between the first switching element and the second switching element, a primary winding of a transformer, and n (n is a natural number greater than or equal to 2) first-order resonance capacitors to n-th-order resonance capacitors. One end of the k-th resonance capacitor (k is a natural number from 1 to n) of the q-th (q is a natural number from 1 to m) resonance circuit connected in parallel is connected in series to the resonance reactor and the primary winding of the transformer, and the other end is connected to the k-th resonance capacitor of the q-th resonance circuit connected in parallel among other circuit elements, so that a k-dimensional multi-phase LLC converter with a phase difference of 360° / Pk is formed by Pk (Pk is an arbitrary natural number) circuit elements.

[0011] In addition, a switching power supply device according to one embodiment of the present invention includes a plurality of half-bridge LLC converters in which a resonant circuit (circuit portion other than a resonant reactor) is connected in parallel as a circuit element. The circuit element includes: a first switching element and a second switching element connected in series to both ends of a DC power supply; a resonant reactor connected at one end to a connection point between the first switching element and the second switching element; and m (m is a natural number greater than 2) resonant circuits connected in parallel and each including a primary winding of a transformer and n (n is a natural number greater than 2) first-order resonant capacitors to n-th-order resonant capacitors connected at the other end of the resonant reactor. One end of the kth-order resonant capacitor (k is a natural number from 1 to n) of the qth (q is a natural number from 1 to m) parallel-connected resonant circuit is connected in series with the resonant inductor and the primary winding of the transformer, and the other end is connected to the kth-order resonant capacitor of the qth resonant circuit in parallel among other circuit elements, so that a k-dimensional multi-phase LLC converter with a phase difference of 360° / Pk is formed by Pk (Pk is an arbitrary natural number) circuit elements.

[0012] Effects of the Invention

[0013] According to one aspect of the present invention, the number of complementary gate drive signals can be reduced to a smaller number than the total number of circuit elements, and the resonant circuits can be connected in parallel to achieve higher output without increasing the number of complementary gate drive signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 1 is a diagram showing a circuit configuration of an embodiment of a switching power supply device.

[0015] Figure 2 It is a description of Figure 1 FIG. 2 is a diagram of a circuit for controlling the operation of a switching power supply device.

[0016] Figure 3 This is a diagram for explaining the multi-dimensionalization (1 to 3 dimensions) of a switching power supply device.

[0017] Figure 4 This is a diagram for explaining the multi-dimensionalization (4 to 6 dimensions) of a switching power supply device.

[0018] Figure 5 This is a diagram for explaining further multi-dimensionalization of the switching power supply device.

[0019] Figure 6 It is a diagram showing another configuration example of circuit elements.

[0020] Figure 7 It is a diagram showing another configuration example of circuit elements.

[0021] Figure 8 It is a diagram showing another configuration example of circuit elements.

[0022] Fig. 9 It is a diagram showing another configuration example of circuit elements.

[0023] Fig.10 This is a diagram for explaining parallel connection and multi-dimensionalization of switching power supply devices. DETAILED DESCRIPTION

[0024] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following embodiments, the same reference numerals are attached to components having the same functions, and description thereof will be omitted as appropriate.

[0025] Reference Figure 1 The switching power supply device 1 of the present embodiment includes a plurality of (Σ) half-bridge LLC converters (hereinafter referred to as circuit elements 10). Each of the 1 to n dimensions of the switching power supply device 1 is configured as a multi-phase LLC converter. That is, the switching power supply device 1 is a multi-phase multiple LLC converter. Here, n is a natural number greater than 2, and the switching power supply device 1 composed of a multi-phase LLC converter of 2 dimensions or more is described below.

[0026] The circuit element 10 includes a high potential input terminal Tin connected to the positive electrode of the DC power supply Vin. + and a low potential input terminal Tin connected to the negative electrode of the DC power supply Vin － A first switching element QH and a second switching element QL are connected in series.

[0027] The circuit element 10 includes a resonance circuit including a resonance reactor Lr having one end connected to a connection point between the first switching element QH and the second switching element QL, a primary winding N1 of a transformer Tr, and n+1 resonance capacitors Cr0 to Crn.

[0028] The circuit element 10 includes a rectifying and smoothing circuit including synchronous rectifying elements SR1 and SR2 for rectifying and smoothing the voltage of the secondary winding N2 of the transformer Tr and an output capacitor Cout.

[0029] exist Figure 1 In the solid-line frame (equivalent to a module), only the main circuit of the circuit element 10 is described. The rectifying and smoothing circuit can adopt a rectifying method such as center-tapped rectification, bridge rectification, voltage double rectification, Cochcroft-Walton rectification, etc.

[0030] At the high potential input terminal Tin + With low potential input terminal Tin －The input capacitor Cin is connected between the two ends of the output capacitor Cout and the high potential output terminal Vout. + and low potential output terminal Vout － connect.

[0031] One end of the resonant capacitor Cr0 is connected in series with the resonant reactor Lr and the primary winding N1 of the transformer Tr, and the other end is connected to the low potential input terminal Tin. － connect.

[0032] One end of the resonant capacitors Cr1 to Crn is connected in series with the resonant reactor Lr and the primary winding N1 of the transformer Tr, and the other end is connected to the bypass terminals T1 to Tn, respectively. The other end (bypass terminal Tk) of the k-th (k is a natural number from 1 to n) resonant capacitor Crk is connected to the other end (bypass terminal Tk) of the k-th resonant capacitor Crk of another circuit element 10, so that a k-dimensional multi-phase LLC converter with a phase difference of 360° / Pk is formed by Pk (Pk is an arbitrary natural number) circuit elements 10. In this specification, regardless of the orthogonality of the dimensions, the n interconnection points of the bypass terminals T1 to Tn are respectively referred to as k-dimensional.

[0033] The total number Σ of the circuit elements 10 is expressed by the following equation (1) using Pk, which is the number of phases per k dimension.

[0034] [Mathematical formula 1]

[0035]

[0036] Reference Figure 2 (a), the switching power supply device 1 includes a control circuit 20 and a selection signal generating circuit 30. The control circuit 20 generates a complementary gate drive signal Gk Pk(k＝1～n) The first switch element QH and the second switch element QL of the Σ circuit elements 10 are turned on and off alternately. The selection signal generation circuit 30 controls the dimension selection circuit 42 through the dimension selection signal Yk, and selects the operation / stop of the circuit element 10 for each dimension. At the same time, the phase selection signal Xk Pk(k＝1～n) The phase selection circuit 41 is controlled to select the operation / stop of Σ circuit elements 10 for each dimension and each phase.

[0037] The phase numbers P1 to Pn of each of the 1 to n dimensions may be different, but by making them all the same, the same complementary gate drive signal G can be used in each dimension. Pk By using the same complementary gate drive signal G Pk, in the case where the control-related circuits are not large-scale, the power can be easily expanded by multi-phase. As for the phase number Pk, even if it is 2 or other divisors of the phase number Pk, other dimensions of complementary gate drive signals G can also be used. Pk(1～n) .

[0038] For example, when the number of phases P1 to Pn of each of the 1 to n dimensions is all set to 3, Figure 2 As shown in (b), the complementary gate drive signals generated by the control circuit 20 are three, namely G1, G2, and G3, and the phase selection signals generated by the selection signal generation circuit 30 are also three, namely X1, X2, and X3.

[0039] In the one-dimensional three-phase LLC converter composed of three circuit elements 10 having only the resonant capacitor Cr1, the phases of the circuit elements 10 differ by 360° / 3. Figure 3 In (a), the circuit elements 10 are represented by cubes of three different densities, and a connection point connecting the other ends (bypass terminals T1) of the resonance capacitors Cr1 to each other is represented by a line penetrating the three cubes.

[0040] In order to expand in the two-dimensional direction, the circuit element 10 having two resonant capacitors Cr1 and Cr2 is connected in one dimension with one resonant capacitor Cr1 connected in the one-dimensional direction and in the other resonant capacitor Cr2 connected in the two-dimensional direction so that the phases do not overlap at the connection point. Figure 3 As shown in (b), three connection points are added in the two-dimensional direction, and a two-dimensional three-phase triple LLC converter is formed by nine circuit elements 10 having six interconnection points. Figure 3 In (b), only the connection points in the 2-dimensional direction are shown.

[0041] Furthermore, in order to expand in the three-dimensional direction, two resonant capacitors Cr1 and Cr2 of the circuit element 10 having three resonant capacitors Cr1, Cr2, and Cr3 are connected in the one-dimensional direction and the two-dimensional direction respectively, and the third resonant capacitor Cr3 is connected to each other in the three-dimensional direction in such a manner that the phases do not overlap at the connection points. Figure 3 As shown in (c), nine interconnection points are added in the three-dimensional direction, and a three-dimensional three-phase nine-layer LLC converter is formed by 27 circuit elements 10 having 27 interconnection points. Figure 3 In (c), only the connection points in the three-dimensional direction are shown.

[0042] Thus, the switching power supply device 1 becomes a multi-phase LLC converter at a certain connection point, and when compared with each other at the connection points, the multi-phase LLC converters overlap to become multiple LLC converters. Therefore, the switching power supply device of this embodiment can be called a multi-phase multiple LLC converter.

[0043] Furthermore, if Figure 3 The 3D three-phase nine-layer LLC converter shown in (b) is represented as a cube. Figure 4 As shown in (a), the 4th dimension can be identified in the same way as the 1st dimension. In order to expand in the 4th dimension, the three resonant capacitors Cr1, Cr2, Cr3 of the circuit element 10 having four resonant capacitors Cr1, Cr2, Cr3, Cr4 are connected in a 3-dimensional manner as described above, and the fourth resonant capacitor Cr4 is connected in the 4th dimension. Thus, a 4-dimensional three-phase twenty-seven-fold LLC converter is formed by three cubes constituting a 3-dimensional three-phase nine-fold LLC converter and a total of 81 circuit elements 10. Regarding the connection points of the 4-dimensional three-phase twenty-seven-fold LLC converter, since the cube of the 3-dimensional three-phase nine-fold LLC converter already contains 27 connection points and there are three, there are 81 connection points, and 27 more are added in the 4-dimensional direction, with a total of 108 connection points. Figure 4 (a) shows one of the connection points in the 4-dimensional direction.

[0044] like Figure 4 As shown in (b), if expanded in the 5-dimensional direction, a 5-dimensional three-phase 81-layer LLC converter is formed by 243 circuit elements 10 with 405 interconnection points. Figure 4 (b) shows one of the connection points in the 5-dimensional direction.

[0045] Furthermore, if Figure 4 As shown in (c), if expanded in the 6-dimensional direction, a 6-dimensional three-phase 243-layer LLC converter is formed by 729 circuit elements 10 with 1458 interconnection points. Figure 4 (c) shows one of the connection points in the 6-dimensional direction.

[0046] Similarly, the 6-dimensional three-phase 243-fold LLC converter expanded to 6 dimensions is represented by a cube, as Figure 5 As shown in FIG. 1 , the number of circuits can be increased to 7, 8, and 9 dimensions. Further high dimensionality can be achieved by treating a multi-dimensional multiple LLC converter composed of 3N (N is a natural number) dimensions as a cube and increasing the dimensional axis. Therefore, if the three-phase LLC converter is n-dimensional, it becomes an n-dimensional three-phase 3 n-1 This allows for higher power without increasing the complementary gate drive signals from three phases.

[0047] In this way, the switching power supply device 1 has a multi-dimensional, fractal structure obtained by overlapping 3-dimensional orthogonal axes. Even if it is expanded to more than 3 dimensions, it is not necessary to set the phase difference to 360° / Σ according to the total number Σ of the circuit elements 10 as in the previous multi-phase method. Since there is no need to prepare a complementary gate drive signal generation circuit for making Σ phase differences, the large-scale circuit related to the control is suppressed. In particular, when the number of phases Pk in each dimension is made the same, by constructing a multi-phase LLC converter with a phase difference of 360° / Pk relative to a certain connection point, a circuit that generates Pk complementary gate drive signals can be used, and the number of circuits can be increased while balancing the current to increase the power.

[0048] The switching power supply device 1 of the present embodiment can be configured as an integrated circuit (e.g., a power supply IC or a system on chip (SoC)) in which semiconductors and magnetic components are mixed in a package of limited size. As a simplified example, a switching power supply device 1 with an output power of 1 kW (kilowatt) can be realized by connecting 10 circuit elements 10 that output 100 W of power. A multi-phase multi-converter composed of an integrated circuit can also be applied to a micro-electromechanical system (MEMS).

[0049] The circuit element 10 of the switching power supply device 1 has a second terminal connected to the low potential input terminal Tin. － In addition to the connected resonant capacitor Cr0, there are also resonant capacitors Cr1 to Crn divided into n. The other end (bypass terminal Tk) of the kth (1 to n) resonant capacitor Crk is connected to the other end (bypass terminal Tk) of the kth resonant capacitor Crk of another circuit element 10, so that a multi-phase LLC converter with a phase difference of 360° / Pk is formed by Pk circuit elements 10. In this case, the total number Σ of the circuit elements 10 constituting the switching power supply device 1 is expressed by the above-mentioned formula (1), and the total number Σc of the interconnection points based on the resonant capacitors Cr1 to Crn is expressed by the following formula (2).

[0050] [Mathematical formula 2]

[0051]

[0052] The resonant frequency ωr when all of the Σ circuit elements 10 of the switching power supply device 1 are operating is expressed by the following equation (3).

[0053] [Mathematical formula 3]

[0054]

[0055] The resonance frequency ωr when the capacitances of the resonance capacitors Cr0 to Crn are equal is expressed by the following equation (4).

[0056] [Formula 4]

[0057]

[0058] According to equations (1) and (2), the total number Σ of the circuit elements 10 and the interconnection points coincide with each other, which satisfies the condition shown in the following equation (5).

[0059] [Mathematical formula 5]

[0060]

[0061] Especially in Figure 1 When the circuit element 10 is modularized as shown in , the total number Σ of the circuit elements 10 and the connection points can be limited to 1:1.

[0062] The circuit element 10 includes the resonant capacitor Cr0, so that it can be operated in a single phase when the load is light (when the output power is low). However, when the single-phase operation is not required, the resonant capacitor Cr0 can be omitted. By omitting the resonant capacitor Cr0, even if the ground potentials of the LLC converters installed separately are different, it is easy to achieve current balance between the LLC converters.

[0063] When the resonant capacitor Cr0 is omitted, the resonant frequency ωr when all the Σ circuit elements 10 of the switching power supply device 1 are in operation is expressed by the following equation (6).

[0064] [Mathematical formula 6]

[0065]

[0066] In addition, the resonance frequency ωr when the capacitances of the resonance capacitors Cr1 to Crn are equal is expressed by the following equation (7).

[0067] [Mathematical formula 7]

[0068]

[0069] Figure 6 The circuit element 10a is a modular circuit element 10a in which m components other than the first switching element QH and the second switching element QL are connected in parallel. Figure 6 In FIG. 1 , only the main circuit of the circuit element 10a is described in the solid-line frame (corresponding to the module).

[0070] The circuit element 10a includes resonant reactors Lr1 to Lr2 connected at one end to a connection point between the first switching element QH and the second switching element QL. m Here, m is a natural number greater than or equal to 2.

[0071] The circuit element 10a includes a resonant reactor Lr q (q is a natural number from 1 to m), transformer Tr q The primary winding N1 q , and n+1 resonant capacitors Cr0 q ~Crn q m resonant circuits.

[0072] The circuit element 10a includes a transformer Tr q The secondary winding N2 q The voltage is rectified and smoothed by the synchronous rectification element SR1 q SR2 q And the output capacitor Cout q The rectifier and smoothing circuits can adopt a rectification method such as center tap rectification, bridge rectification, voltage doubler rectification, Cockcroft Walton rectification, etc.

[0073] Resonance capacitor Cr0 q One end of the resonant reactor Lr q , Transformer Tr q The primary winding N1 q Connect in series, and the other end is connected to the low potential input terminal Ti n － connect.

[0074] Resonance capacitor Cr1 q ~Crn q One end of the resonant reactor Lr q , Transformer Tr q The primary winding N1 q Connect in series, and connect the other end to the bypass terminal T1 q ~Tn q The kth (k is a natural number from 1 to n) resonant capacitor Crk is connected. q The other end (bypass terminal Tk q ) and the kth resonant capacitor Crk of other circuit elements 10 q The other end (bypass terminal Tk q ) are connected so that a k-dimensional multi-phase LLC converter with a phase difference of 360° / Pk is formed by Pk (Pk is an arbitrary natural number) circuit elements 10a.

[0075] When single-phase operation is not required, the resonant capacitors Cr01 to Cr02 of the circuit element 10a are m Can also be omitted. Figure 7 The resonant capacitors Cr01 to Cr02 are omitted from the circuit element 10a. m Circuit element 10b.

[0076] The circuit elements 10a and 10b perform power amplification through m resonant circuits. m Assuming the same capacitance Lr, and the current flowing through is i, the resonant reactor Lr q The magnetic flux Φ is expressed by the following equation (8).

[0077] [Mathematical formula 8]

[0078] Φ=Lr·i---(8)

[0079] Figure 8 as well as Fig. 9 The resonant reactor Lr1~Lr m The circuit elements 10c and 10d of one resonant reactor are collectively represented by reference symbol "Lr / m". m When the capacitance Lr is the same, the capacitance of the resonant reactor "Lr / m" is 1 / m of the aforementioned Lr. In the circuit element 10c, Figure 6 The resonant reactors Lr1 to Lr2 of the circuit element 10a shown in FIG. m are summarized as one resonant reactor "Lr / m". In circuit element 10d, Figure 7 The resonant reactors Lr1 to Lr2 of the circuit element 10b shown in FIG. m Summarized as resonant reactor "Lr / m".

[0080] Since the current flowing through the resonant reactor "Lr / m" flows through the resonant reactor Lr1~Lr m Therefore, the magnetic flux Φ of the resonant reactor "Lr / m" is expressed by the following formula (9), which is the same as the magnetic flux Φ obtained by formula (8).

[0081] [Number 9]

[0082]

[0083] That is, the resonant reactors of the circuit element 10c and the circuit element 10d are the same as the resonant reactor Lr of the circuit element 10. Therefore, in the switching power supply device 1 composed of the circuit element 10c, the resonant frequency ωr when all the Σ circuit elements 10c are in operation is the same as the above-mentioned equations (3) and (4). In the switching power supply device 1 composed of the circuit element 10d, the resonant frequency ωr when all the Σ circuit elements 10d are in operation is the same as the above-mentioned equations (6) and (7).

[0084] Thus, the m resonant reactors Lr1 to Lr2 of the circuit elements 10a and 10b are m With resonant capacitor Cr01~Cr0 m Regardless of the presence or absence of circuit elements 10c and 10d, they can be combined into one resonant inductor "Lr / m". The capacitance of the resonant inductor "Lr / m" of circuit elements 10c and 10d can be 1 / m of the capacitance of the resonant inductor Lr of circuit element 10. Therefore, the switching power supply device 1 composed of circuit elements 10c and 10d can make the total size of the resonant inductor 1 / m, and the total weight 1 / m relative to the switching power supply device 1 of the same dimension composed of circuit element 10. That is, when the power is expanded, the more parallel the switching power supply device 1 is, the smaller the resonant inductor Lr can be, and the more dimensional it is, the smaller the resonant capacitor Cr can be. When the power is specified, the more parallel the switching power supply device 1 is, the smaller the transformers Tr1~T m Become smaller, suitable for integration, and make the size of components smaller.

[0085] Fig.10 The circuit elements 10a to 10d are represented by cubes, and the cubes with different phases are represented by three different densities. The number of parallel connected cubes is m. Fig.10 It can be seen that the parallelization of the resonant circuits in the circuit elements 10a to 10d is equivalent to increasing the number of dimensions by one.

[0086] As described above, the present embodiment has a plurality (Σ) of half-bridge LLC converters in which the resonant circuit is connected in parallel as circuit elements 10a and 10b. The circuit elements 10a and 10b have: a first switching element QH and a second switching element QL connected in series between the positive and negative electrodes of a DC power supply Vin; and a resonant reactor Lr, each of which has one end connected to the connection point between the first switching element QH and the second switching element QL, a primary winding N1 of a transformer Tr, and m (m is a natural number greater than 2) parallel resonant circuits of n (n is a natural number greater than 2) first-order resonant capacitors (resonant capacitor Cr1) to n-th-order resonant capacitors (resonant capacitor Crn). The resonant capacitor Crk of the q-th (q is a natural number from 1 to m) parallel resonant circuit q (k is a natural number from 1 to n) and the resonant reactor Lr q , Transformer Tr q The primary winding N1 q The resonant capacitor Crk of the qth resonant circuit connected in series. q The other end of the resonant capacitor Crk of the qth resonant circuit connected in parallel with other circuit elements 10a and 10b q The circuit elements are connected so that a k-dimensional multi-phase LLC converter having a phase difference of 360° / Pk is formed by Pk (Pk is an arbitrary natural number) circuit elements.

[0087] According to this structure, the present embodiment can make the complementary gate drive signal less than the total number Σ of the circuit elements 10a and 10b, and does not increase the complementary gate drive signal. The present embodiment can achieve high power of the circuit elements 10a and 10b by connecting the resonant circuits in parallel. The present embodiment can increase the total number Σ of the circuit elements 10, achieve current balance between the circuit elements 10, and achieve high power.

[0088] In addition, the circuit elements 10c and 10d of the present embodiment have a plurality (Σ) of half-bridge LLC converters that connect the resonant circuit (circuit parts other than the resonant reactor "Lr / m") in parallel as the circuit elements 10a and 10b. The circuit elements 10c and 10d have: a first switching element QH and a second switching element QL connected in series between the positive and negative electrodes of the DC power supply Vin; a resonant reactor "Lr / m" having one end connected to the connection point between the first switching element QH and the second switching element QL; and m (m is a natural number greater than 2) parallel resonant circuits each including the primary winding N1 of the transformer Tr and n (n is a natural number greater than 2) first-order resonant capacitors (resonant capacitor Cr1) to n-th-order resonant capacitors (resonant capacitor Crn) connected to the other end of the resonant reactor "Lr / m". The resonant capacitor Crk of the q-th (q is a natural number from 1 to m) parallel resonant circuit q (k is a natural number from 1 to n) and the resonant reactor Lr q , Transformer Tr q The primary winding N1 q The resonant capacitor Crk of the qth resonant circuit connected in series. q The other end of the resonant capacitor Crk of the qth resonant circuit connected in parallel with other circuit elements 10a and 10b q The circuit elements are connected so that a k-dimensional multi-phase LLC converter having a phase difference of 360° / Pk is formed by Pk (Pk is an arbitrary natural number) circuit elements.

[0089] According to this structure, the switching power supply device 1 composed of the circuit elements 10c and 10d can reduce the total size of the resonant reactor to 1 / m, and can also reduce the total weight to 1 / m, compared with the switching power supply device 1 of the same dimension composed of the circuit element 10. That is, when the power is increased, the more parallel the switching power supply device 1 is, the smaller the resonant reactor Lr can be, and the more multi-dimensional the switching power supply device 1 is, the smaller the resonant capacitor Cr can be.

[0090] Furthermore, according to the present embodiment, the total number Σ of the circuit elements 10 a to 10 d is the product of the number of phases included in each dimension (Σ=P1×P2×···×Pn).

[0091] According to this configuration, the dimension can be increased to increase the total number Σ of the circuit elements 10 a to 10 d exponentially, thereby being able to cope with an increase in power.

[0092] As mentioned above, although this invention was demonstrated using the specific embodiment, the said embodiment is an example, It is a matter of course that it can be implemented with modification within the range which does not deviate from the summary of this invention.

[0093] In the above-described embodiment, the resonant reactor Lr is physically provided in each circuit element 10 , but the resonant reactor Lr may utilize the leakage inductance of the transformer instead.

[0094] Description of Reference Numerals

[0095] 1: switching power supply device, 10, 10a, 10b, 10c, 10d: circuit element (half-bridge LLC converter), 20: control circuit, 30: selection signal generation circuit, 41: phase selection circuit, 42: dimension selection circuit, Cin: input capacitor, Cout: output capacitor, Cr0~Crn: resonant capacitor, Lr: resonant inductor, N1: primary winding, N2: secondary winding, QH: first switching element, QL: second switching element, SR1, SR2: synchronous rectification element, Tr: transformer, T1~Tn: bypass terminal, Tin + : High potential input terminal, Tin － : Low potential input terminal, Vout + : High potential output terminal, Vout － : Low potential output terminal, Vin: DC power supply.

Claims

1. A switching power supply device, comprising a plurality of half-bridge LLC converters as circuit elements, wherein: The half-bridge LLC converter features: a first switching element and a second switching element connected in series to both ends of a DC power supply; and m resonance circuits connected in parallel, each including a resonance reactor having one end connected to a connection point between the first switching element and the second switching element, a primary winding of a transformer, and n first-order resonance capacitors to n-th-order resonance capacitors, wherein n is a natural number greater than 2, and m is a natural number greater than 2, One end of the k-th resonant capacitor of the q-th resonant circuit in parallel is connected in series with the resonant inductor and the primary winding of the transformer, and the other end is connected to the k-th resonant capacitor of the q-th resonant circuit in parallel in other circuit elements, so that a k-dimensional multi-phase LLC converter with a phase difference of 360° / Pk is formed by Pk circuit elements, wherein q is a natural number from 1 to m, k is a natural number from 1 to n, and Pk is an arbitrary natural number.

2. A switching power supply device, comprising a plurality of half-bridge LLC converters as circuit elements, wherein: The half-bridge LLC converter features: A first switching element and a second switching element connected in series to both ends of a DC power supply; A resonant reactor having one end connected to a connection point between the first switching element and the second switching element; as well as m resonant circuits connected in parallel and connected to the other end of the resonant reactor, each including a primary winding of a transformer and n first-order resonant capacitors to n-th-order resonant capacitors, wherein n is a natural number greater than 2 and m is a natural number greater than 2, One end of the k-th resonant capacitor of the q-th resonant circuit in parallel is connected in series with the resonant inductor and the primary winding of the transformer, and the other end is connected to the k-th resonant capacitor of the q-th resonant circuit in parallel in other circuit elements, so that a k-dimensional multi-phase LLC converter with a phase difference of 360° / Pk is formed by Pk circuit elements, wherein q is a natural number from 1 to m, k is a natural number from 1 to n, and Pk is an arbitrary natural number.

3. The switching power supply device according to claim 1 or claim 2, wherein: The total number of circuit elements is the product of the number of phases contained in each dimension.

4. The switching power supply device according to claim 3, wherein: The total number of resonant circuits is the product of the number of phases contained in each dimension and the number of parallel connections m, where: m is a natural number greater than or equal to 2.

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