JP2018011400A - Single phase inverter unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress unbalance of current effectively.SOLUTION: A first phase control unit 11 and a second phase control unit 12 include, respectively, multiple arm components 21-23, 61-63, output conductors 26, 66, P conductors 24, 64, and N conductors 25, 65. The P conductors 24, 64 of the first and second phase control units 11, 12, and at least one of the N conductors 25, 65 are connected on the opposite side to external output terminals 134, 234.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a single-phase inverter unit that is used for induction heating and outputs a large current.

  Japanese Patent Application Laid-Open No. 2004-228620 proposes that the wiring is configured so that the sharing current of the switching element and the capacitor is equalized by pairing the switching element and the capacitor and connecting them in parallel. For example, the sharing current unbalance is suppressed by equalizing the wiring inductance from the switch element to the capacitor.

Japanese Patent No. 3277524

In order to use at a high frequency, it is required to reduce the wiring inductance in order to suppress parasitic vibration due to the wiring inductance, local heating due to the magnetic flux, and the like. For this reason, as in the above-described prior art, it is unsuitable for use at a high frequency to suppress the unbalance of the shared current using the wiring inductance.
An object of the present invention is to effectively suppress current imbalance.

  A single-phase inverter unit according to one embodiment of the present invention includes a plurality of modules each including a high-potential side switch element and a low-potential side switch element connected in series, and output terminals of the plurality of modules connected in parallel to one end side. A pair of control units including an output conductor having an external output terminal, a positive conductor that connects the positive terminals of the modules in parallel, and a negative conductor that connects the negative terminals of the modules in parallel are provided. Then, one or both of the positive electrode conductors and the negative electrode conductors of both control units are connected on the module side connected to the other end side of the output conductor.

  According to the present invention, since at least one of the positive electrode conductors and the negative electrode conductors is connected on the side opposite to the external output terminal, current imbalance can be effectively suppressed.

It is a perspective view of a single phase inverter unit. It is a figure which shows typically the cross section of N conductor and P conductor. It is a figure which shows the equivalent circuit of a single phase inverter unit. It is a perspective view of the single phase inverter unit which shows a comparative example. It is a figure which shows the equivalent circuit of the single phase inverter unit which shows a comparative example. It is the figure which showed the cross section of the output conductor typically.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Each drawing is schematic and may be different from the actual one. Further, the following embodiments exemplify apparatuses and methods for embodying the technical idea of the present invention, and the configuration is not specified as follows. That is, the technical idea of the present invention can be variously modified within the technical scope described in the claims.

"Constitution"
FIG. 1 is a perspective view of a single-phase inverter unit.
The single-phase inverter unit 10 includes a first phase control unit 11 (U phase) and a second phase control unit 12 (V phase) in which positive electrodes and negative electrodes are connected to each other.
The first phase controller 11 includes a first arm component 21, a second arm component 22, a third arm component 23, a P conductor 24 (positive conductor), and an N conductor 25 (negative conductor). ) And an output conductor 26.
The first arm constituent part 21, the second arm constituent part 22, and the third arm constituent part 23 are arranged in order at predetermined intervals along a predetermined arrangement direction (parallel arrangement). Here, the direction orthogonal to the arrangement direction is defined as the unit width direction.

  The first arm component 21 has a module 31 and a DC capacitor 41. The module 31 is packaged so as to extend along the unit width direction, and includes a high-potential side semiconductor switch element and a low-potential side semiconductor switch element connected in series. Specifically, wide band gap semiconductor elements such as SiC-MOSFET and IGBT can be applied to the semiconductor switch element in addition to Si-MOSFET and Si-IGBT. On the upper surface of the module 31, a P terminal 111 (positive terminal), an N terminal 121 (negative terminal), and an output terminal 131 are provided in order from the outer side to the inner side in the unit width direction. The P terminal 111 is connected to the drain of the semiconductor switch element on the high potential side, and the N terminal 121 is connected to the source of the semiconductor switch element on the low potential side. The output terminal 131 is connected between the source of the semiconductor switch element on the high potential side and the drain of the semiconductor switch element on the low potential side. The DC capacitor 41 is a low-inductance capacitor that is packaged in a substantially rectangular parallelepiped shape, is disposed above the P terminal 111, and is connected in parallel to the P terminal 111 and the N terminal 121 of the module 31.

  Similarly, the second arm component 22 includes a module 32 and a DC capacitor 42. A P terminal 112, an N terminal 122, and an output terminal 132 are provided on the upper surface of the module 32. The DC capacitor 42 is connected in parallel to the P terminal 112 and the N terminal 122 of the module 32. The third arm component 23 includes a module 33 and a DC capacitor 43. A P terminal 113, an N terminal 123, and an output terminal 133 are provided on the upper surface of the module 33. The DC capacitor 43 is connected in parallel to the P terminal 113 and the N terminal 123 of the module 33.

  The DC capacitor 41 includes a lead part 51 drawn downward, and a P terminal 141 and an N terminal 151 formed in the lead part 51. The lead portion 51 has a structure in which a lead plate for a P terminal and a lead plate for an N terminal are brought into close contact with each other through an insulator, but here, the lead portion 51 is drawn in a sheet shape for convenience. Yes. Similarly, the DC capacitor 42 includes a lead portion 52, a P terminal 142, and an N terminal 152, and the DC capacitor 43 includes a lead portion 53, a P terminal 143, and an N terminal 153.

  The N conductor 25 is disposed on the upper surface of the modules 31 to 33 and extends in the arrangement direction and covers a range corresponding to the P terminals 111, 112, 113 and the N terminals 121, 122, 123. . The P conductor 24 is disposed on the upper surface of the N conductor 25, extends in the arrangement direction, and covers a range corresponding to the P terminals 111, 112, and 113. The P conductor 24 and the N conductor 25 are laminated and laminated via an insulating film sheet to reduce the inductance. The P conductor 24 and the N conductor 25 are preferably laminated on the entire surface including the end surfaces with an insulating fill sheet. The N conductor 25 is connected to each of the N terminals 121, 122, and 123 of each module through bolts. The P conductor 24 is connected to each of the P terminals 111, 112, and 113 of each module via a bolt. The N conductor 25 is insulated from bolts connected to the P terminals 111, 112, and 113.

The P conductor 24 is formed with a bent portion 27 that rises upward from an outer edge in the unit width direction. The bent portion 27 contacts the inner surface side in the unit width direction of the lead portion 51, and is connected to each of the P terminals 141, 142, and 143 of each DC capacitor via a bolt. The N conductor 25 is formed with a bent portion 28 that rises upward along the inner surface side of the bent portion 27 in the unit width direction. The bent portion 28 contacts the outer surface side in the unit width direction of the lead portion 51, and is connected to each of the N terminals 151, 152, and 153 of the DC capacitors via bolts. The bent portion 27 and the bent portion 28 are laminated by being laminated with an insulating film sheet interposed therebetween.
The output conductor 26 is disposed on the top surfaces of the modules 31 to 33, extends in the arrangement direction, and is connected to the output terminals 131, 132, and 133 of each module. The output conductor 26 has one end in the arrangement direction extended outward from the module 33, and includes an external output terminal 134 at the extended portion.

The second phase control unit 12 is disposed opposite to the first phase control unit 11 and passes through the center in the unit width direction and is reversed with respect to the center line L along the arrangement direction. Make a configuration. Therefore, although detailed description is omitted, the second phase control unit 12 has the same configuration as the first phase control unit 11. That is, the second phase controller 12 includes the first arm component 61, the second arm component 62, the third arm component 63, the P conductor 64 (positive conductor), and the N conductor 65 ( A negative electrode conductor) and an output conductor 66.
The first arm component 61 has a module 71 and a DC capacitor 81, the second arm component 62 has a module 72 and a DC capacitor 82, and the third arm component 63 has a module. 73 and a DC capacitor 83.

A P terminal 211, an N terminal 221, and an output terminal 231 are provided on the upper surface of the module 71. A P terminal 212, an N terminal 222, and an output terminal 232 are provided on the upper surface of the module 72. A P terminal 213, an N terminal 223, and an output terminal 233 are provided on the upper surface of the module 73.
The DC capacitor 81 includes a lead portion 91, a P terminal 241, and an N terminal 251, the DC capacitor 82 includes a lead portion 92, a P terminal 242, and an N terminal 252, and the DC capacitor 83 includes a lead portion 93, P A terminal 243 and an N terminal 253 are provided.
A bent portion 67 is formed on the P conductor 64, and a bent portion 68 is formed on the N conductor 65. The output conductor 66 includes an external output terminal 234.

The first-phase P conductor 24 and the second-phase P conductor 64 are arranged on the other end side in the arrangement direction opposite to the external output terminals 134 and 234 formed on the modules 33 and 73 side. 31 and 71 side are connected by the connection part 13 extended along the unit width direction. Accordingly, the first-phase P conductor 24 and the second-phase P conductor 64 are integrally connected at the connection portion 13 and formed in a substantially U shape in plan view. The first-phase N conductor 25 and the second-phase N conductor 65 are arranged on the other end side in the arrangement direction opposite to the external output terminals 134 and 234 formed on the modules 33 and 73 side. 31 and 71 side are connected by the connection part 14 extended along a unit width direction. Therefore, the first-phase N conductor 25 and the second-phase N conductor 65 are integrally connected at the connection portion 14 and formed in a substantially U shape in plan view. The connection portion 13 on the P conductor side and the connection portion 14 on the N conductor side are laminated and laminated via an insulating film sheet.
The first-phase modules 31 to 33 and the second-phase modules 71 to 73 are arranged on the upper surface of the cooling plate 15 (cooling unit). The cooling plate 15 can be applied with an air cooling type provided with fins or a water cooling type with a water cooling jacket.

FIG. 2 is a diagram schematically showing a cross section of the N conductor and the P conductor.
The P conductor 24 and the N conductor 25 are laminated by the insulating film sheet 101. The N conductor 25 is formed with a through hole 103 larger than the bolt diameter in order to ensure insulation from the bolt 102 connected to the P terminal 111. That is, the bolt 102 is fastened to the P conductor 24 and the P terminal 111 while being insulated from the N conductor 25. N conductor 25 is connected to N terminal 121 via bolt 104.

FIG. 3 is a diagram showing an equivalent circuit of the single-phase inverter unit.
In the module 31, the semiconductor switch element on the high potential side is Q11, the semiconductor switch element on the low potential side is Q21, and the capacitor element is C11. The wiring impedance of the semiconductor switch element Q11 is SZ11, the wiring impedance of the semiconductor switch element Q21 is SZ21, and the wiring impedance of the capacitor element C11 is CZ11. In the module 32, the semiconductor switch element on the high potential side is Q12, the semiconductor switch element on the low potential side is Q22, and the capacitor element is C12. The wiring impedance of the semiconductor switch element Q12 is SZ12, the wiring impedance of the semiconductor switch element Q22 is SZ22, and the wiring impedance of the capacitor element C12 is CZ12. In the module 33, the semiconductor switch element on the high potential side is Q13, the semiconductor switch element on the low potential side is Q21, and the capacitor element is C13. The wiring impedance of the semiconductor switch element Q13 is SZ13, the wiring impedance of the semiconductor switch element Q23 is SZ23, and the wiring impedance of the capacitor element C13 is CZ13.

  In the P conductor 24, the wiring impedance between the first arm constituent part 21 and the second arm constituent part 22 is LZ11, and the wiring between the second arm constituent part 22 and the third arm constituent part 23 is used. The impedance is LZ12. In the N conductor 25, the wiring impedance between the first arm constituent part 21 and the second arm constituent part 22 is LZ21, and the wiring between the second arm constituent part 22 and the third arm constituent part 23 is used. The impedance is LZ22. In the output conductor 26, the wiring impedance between the first arm component 21 and the second arm component 22 is LZ21, and the wiring between the second arm component 22 and the third arm component 23 The impedance is LZ22.

  In the module 71, the semiconductor switch element on the high potential side is Q31, the semiconductor switch element on the low potential side is Q41, and the capacitor element is C31. The wiring impedance of the semiconductor switch element Q31 is SZ31, the wiring impedance of the semiconductor switch element Q41 is SZ41, and the wiring impedance of the capacitor element C31 is CZ31. In the module 72, the semiconductor switch element on the high potential side is Q32, the semiconductor switch element on the low potential side is Q42, and the capacitor element is C32. The wiring impedance of the semiconductor switch element Q32 is SZ32, the wiring impedance of the semiconductor switch element Q42 is SZ42, and the wiring impedance of the capacitor element C32 is CZ32. In the module 73, the semiconductor switch element on the high potential side is Q33, the semiconductor switch element on the low potential side is Q43, and the capacitor element is C33. The wiring impedance of the semiconductor switch element Q33 is SZ33, the wiring impedance of the semiconductor switch element Q43 is SZ43, and the wiring impedance of the capacitor element C33 is CZ33.

In the P conductor 64, the wiring impedance between the first arm constituent part 61 and the second arm constituent part 62 is LZ41, and the wiring between the second arm constituent part 62 and the third arm constituent part 63 is used. The impedance is LZ42. In the N conductor 65, the wiring impedance between the first arm constituent part 61 and the second arm constituent part 62 is LZ51, and the wiring between the second arm constituent part 62 and the third arm constituent part 63 is used. The impedance is LZ52. In the output conductor 66, the wiring impedance between the first arm component 61 and the second arm component 62 is LZ61, and the wiring between the second arm component 62 and the third arm component 63 is The impedance is LZ62.
The wiring impedance between the positive electrodes of the connection unit 13, that is, the first phase control unit 11 and the second phase control unit 12, is LZ71. The wiring impedance between the negative electrodes of the connection unit 14, that is, the first phase control unit 11 and the second phase control unit 12, is LZ72.

<Effect>
Next, operational effects will be described.
First, the case where the wiring impedance LZ71 on the positive electrode side and the wiring impedance LZ71 on the negative electrode side are unequal will be described. For example, it is assumed that the wiring impedance LZ72 on the negative electrode side is larger than the wiring impedance LZ71 on the positive electrode side. When the semiconductor switch elements Q11 to Q13 and Q41 to Q43 are conducting, the current output from the U-phase first phase control unit 11 flows to the load circuit and then returns to the V-phase second phase control unit 12 . Then, the semiconductor switch elements Q41 to Q43 first flow through the capacitor elements C31 to C33, and then pass through the semiconductor switch elements Q11 to Q13 and flow to the U phase.

  Here, the currents flowing through the semiconductor switch elements and the capacitor elements before entering the V-phase second phase control unit 12 and exiting the V-phase second phase control unit 12 are the wiring impedances LZ61, LZ62, LZ41, Two of LZ42, LZ51, and LZ52 must be passed. Therefore, current imbalance hardly occurs in each semiconductor switch element and each capacitor element. This is the same when entering the U-phase first phase control unit 11 and exiting the U-phase first phase control unit 11. The same applies when the semiconductor switch elements Q21 to Q23 and Q31 to Q33 are conducting. Further, the same applies when the wiring impedance LZ71 on the positive electrode side is larger than the wiring impedance LZ72 on the negative electrode side.

  Next, a case where the wiring impedance LZ71 on the positive electrode side and the wiring impedance LZ71 on the negative electrode side are equal will be described. When the semiconductor switch elements Q11 to Q13 and Q41 to Q43 are conducting, the current output from the U-phase first phase control unit 11 flows to the load circuit and then returns to the V-phase second phase control unit 12 . Two of the wiring impedances LZ61, LZ62, LZ41, LZ42, LZ51, and LZ52 and the wiring impedances LZ71 and LZ72 before entering the V-phase second phase control unit 12 and exiting from the U-phase first phase control unit 11 One of them and two of the wiring impedances LZ11, LZ12, LZ21, LZ22, LZ31, and LZ32 always pass through a total of five. Therefore, current imbalance is less likely to occur in each semiconductor switch element and each capacitor element. In particular, in this case, the current is diverted to the capacitor elements C11 to C13 and C31 to C33. This is the same when entering the U-phase first phase control unit 11 and exiting the U-phase first phase control unit 11. The same applies when the semiconductor switch elements Q21 to Q23 and Q31 to Q33 are conducting.

Next, a comparative example will be described.
FIG. 4 is a perspective view of a single-phase inverter unit showing a comparative example.
Here, only the U-phase first phase control unit 11 is shown, and the V-phase second phase control unit 12 is not shown. The difference from FIG. 1 is the connection position between the P conductors and the connection position between the N conductors. Specifically, the P conductors and the N conductors are connected at the center in the arrangement direction.
The P conductor 24 is formed with a bent portion 16 that faces the bent portion 27 on the upper surface of the module 32 and rises upward from an inner edge in the unit width direction. The bent portion 16 is formed with a P terminal 161 connected to the P conductor in the V-phase second phase control portion 12 (not shown). The N conductor 25 is formed with a bent portion 17 that rises upward along the inner surface side in the unit width direction of the bent portion 16. The bent portion 17 is formed with an N terminal 162 connected to the N conductor in the V-phase second phase control unit 12 (not shown). The bent portion 16 and the bent portion 17 are laminated by being laminated via an insulating film sheet.

FIG. 5 is a diagram showing an equivalent circuit of a single-phase inverter unit showing a comparative example.
Here, the wiring impedance between the positive electrodes of the bent portion 16, that is, the first phase control unit 11 and the second phase control unit 12, is LZ81. The wiring impedance between the negative electrodes of the bent portion 17, that is, the first phase control unit 11 and the second phase control unit 12, is LZ82.
A current flow in the comparative example will be described.
When the semiconductor switch elements Q11 to Q13 and Q41 to Q43 are conducting, the current output from the U-phase first phase control unit 11 flows to the load circuit and then returns to the V-phase second phase control unit 12. . Then, the semiconductor switch elements Q41 to Q43 first flow through the capacitor elements C31 to C33, and then pass through the semiconductor switch elements Q11 to Q13 and flow to the U phase. Alternatively, the semiconductor switch elements Q41 to Q43 first flow through the capacitor elements C11 to C13, and then pass through the semiconductor switch elements Q11 to Q13 and flow to the U phase. At this time, due to the influence of the wiring impedances LZ61, LZ41, LZ51, LZ31, LZ11, and LZ21, the third arm component 23 close to the external output terminal 134 and the second arm component 22 located in the center in the arrangement direction. It becomes easy to flow current. That is, current easily flows through the semiconductor switch elements and capacitor elements of some arm components, resulting in current imbalance.

On the other hand, in the embodiment of FIGS. 1 and 3, the positive conductors and the negative conductors are connected on the side opposite to the external output terminals 134 and 234, so that only a part of the arm components have a current. Can be prevented from flowing easily. That is, current imbalance can be effectively suppressed.
The P conductor 24 and the N conductor 25 (or the P conductor 64 and the N conductor 65), the bent portion 27 and the bent portion 28 (the bent portion 67 and the bent portion 68), and the connecting portion 13 and the connecting portion 14 are respectively an insulating film sheet. Are stacked and laminated. As a result, space saving can be realized, and the assembly work time can be shortened by reducing the number of parts.
Since each module is arranged on the upper surface of the cooling plate 15, overheating of each semiconductor switch element can be suppressed.

<Modification>
In the above embodiment, the output conductor 26 of the first phase control unit 11 and the output conductor 66 of the second phase control unit 12 are provided separately, but the present invention is not limited to this. You may overlap a part via an insulating material.
FIG. 6 is a diagram schematically showing a cross section of the output conductor.
Here, a part of the output conductor 26 of the first phase control unit 11 is overlapped with a part of the output conductor 66 of the second phase control unit 12, and both are laminated via the insulating film sheet 101. Thereby, shortening of the assembly work time by reduction of a number of parts can be aimed at.

In the above embodiment, both the positive electrodes and the negative electrodes of the first phase control unit 11 and the second phase control unit 12 are connected on the side opposite to the output terminal, but the present invention is not limited to this. Absent. That is, it is only necessary that at least one of the positive electrodes and the negative electrodes can be connected on the side opposite to the output terminal.
In the above embodiment, the P conductor 24 is overlaid on the N conductor 25, but the present invention is not limited to this, and the N conductor 25 may be overlaid on the P conductor 24. Accordingly, it is necessary to match the relationship between the N conductor 65 and the P conductor 64 and the relationship between the connection portion 14 and the connection portion 13.

In the above embodiment, in the module 31, the P terminal 111 and the N terminal 121 are formed in order from the outside in the unit width direction to the inside, but the present invention is not limited to this. The N terminal 121 and the P terminal 111 may be formed in order from the outside in the unit width direction to the inside. In the module 31, the output terminal 131, the N terminal 121, and the P terminal 111 are arranged in the order from the outside in the unit width direction to the inside, or the output terminal 131, the P terminal 111, And the N terminal 121 may be formed in this order. Along with this, in each of the modules 32, 33, 71 to 73, it is necessary to match the arrangement of the respective P terminals and N terminals.
In the above embodiment, the three arm components are connected in parallel, but the present invention is not limited to this, and only two arm components are connected in parallel, or four or more arm components are connected. You may connect in parallel.

  Although the present invention has been described with reference to a limited number of embodiments, the scope of rights is not limited thereto, and modifications of the embodiments based on the above disclosure are obvious to those skilled in the art.

  DESCRIPTION OF SYMBOLS 10 ... Single phase inverter unit, 11 ... 1st phase control part, 12 ... 2nd phase control part, 13 ... Connection part, 14 ... Connection part, 15 ... Cooling plate, 16, 17 ... Bending part, 21-23 ... Arm Component part, 24 ... P conductor, 25 ... N conductor, 26 ... Output conductor, 27, 28 ... Bending part, 31-33 ... Module, 41-43 ... DC capacitor, 51-53 ... Lead part, 61-63 ... Arm Component part, 64 ... P conductor, 65 ... N conductor, 66 ... Output conductor, 67, 68 ... Bending part, 71-73 ... Module, 81-83 ... DC capacitor, 91-93 ... Lead part, 101 ... Insulating film sheet , 102 ... Bolt, 103 ... Through-hole, 104 ... Bolt, 111 to 113 ... P terminal, 121 to 123 ... N terminal, 131 to 133 ... Output terminal, 134 ... External output terminal, 141 to 143 ... P terminal 151-153 ... N terminal, 161 ... P terminal, 162 ... N terminal, 211-213 ... P terminal, 221-223 ... N terminal, 231-233 ... output terminal, 234 ... external output terminal, 241-243 ... P terminal 251 to 253... N terminal, LZ11, LZ12, LZ21, LZ22, LZ31, LZ32, LZ41, LZ42, LZ51, LZ52, LZ61, LZ62, LZ71, LZ72, LZ81, LZ82... Wiring impedance, Q11 to Q13. Q21 to Q23 ... Semiconductor switch element, Q31 to Q33 ... Semiconductor switch element, Q41 to Q43 ... Semiconductor switch element, C11 to C13 ... Capacitor element, C31 to C33 ... Capacitor element,

Claims (8)

A plurality of modules incorporating a high potential side switch element and a low potential side switch element connected in series; and
An output conductor in which the output terminals of the plurality of modules are connected in parallel and an external output terminal is formed on one end side;
A positive conductor for connecting the positive terminals of the modules in parallel;
A negative conductor for connecting the negative terminals of the module in parallel;
A pair of control units having
A single-phase inverter unit characterized in that one or both of the positive electrode conductors and the negative electrode conductors of both control units are connected on the module side connected to the other end side of the output conductor.   2. The single-phase inverter unit according to claim 1, wherein a part of the output conductors of the two control units is overlapped with an insulating material.   Both the positive conductors and the negative conductors of the two control parts are connected on the module side connected to the other end of the output conductor, and the connection part between the positive conductors and the connection part between the negative conductors are insulated. The single-phase inverter unit according to claim 1 or 2, wherein the single-phase inverter unit is superposed via a material.   A capacitor connected between a positive electrode terminal and a negative electrode terminal of the module, wherein the positive electrode conductor and the negative electrode conductor are overlapped with an insulating material at a portion to which the capacitor is connected; The single phase inverter unit according to any one of claims 1 to 3.   The single-phase inverter unit according to any one of claims 2 to 4, wherein the insulating material is formed of a laminated film-like insulating sheet.   6. The plurality of modules of the two control units, wherein the positive electrode terminal, the negative electrode terminal, and the surface on which the output terminal is not formed are arranged on a cooling unit. The single-phase inverter unit described in the section.   2. The module according to claim 1, wherein terminals are formed on one side in the order of positive electrode terminal, negative electrode terminal, output terminal or negative electrode terminal, positive electrode terminal, and output terminal, and the modules constituting the control unit are arranged in parallel. The single phase inverter unit as described in any one of 1-6.   The single-phase inverter unit according to any one of claims 1 to 7, wherein the both control units have modules arranged so that the output terminals face each other.

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