JP2011119477A - Reactor, and noise filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reactor with high noise suppressing effect without increasing an arrangement space, the number of components and cost. <P>SOLUTION: A gap (24) of a core (2-1) is formed so that the core (2-1) functions as a closed magnetic path core on at least one magnetic path formed by a common mode current of power lines (3(U), 3(V)), so that the core (2-1) functions as an open magnetic path core on at least one magnetic path generated by a normal mode current of the power lines (3(U), 3(V)), so that the core (2-1) functions as a closed magnetic path core on at least one magnetic path generated by a current of a ground line (3(E)), and so that the core (2-1) functions as a closed magnetic path core on at least one magnetic path generated by a current flowing in one direction through the power lines (3(U), 3(V)) and the ground line (3(E)) (leakage current). <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a noise reduction technique, and relates to a reactor inserted in a power line or a ground line and a reactor used in a noise filter.

Hereinafter, a power conversion device will be described as an example.
It is known that a power converter generates conductive noise and radioactive noise with the operation of a switching element such as an IGBT. These noises have adverse effects such as malfunction, deterioration, and damage on devices connected to the same system, loads such as a motor that supplies power from the power converter, and peripheral devices.

As solutions for the above problems, the following methods 1 to 4 have been proposed. These techniques have a reduction effect for different modes of current.
Method 1:
Connect a reactor to each phase of the power line (normal mode reactor).
By this method, noise components flowing through each phase of the power line can be reduced. That is, noise of a current component generally called a normal mode current can be reduced (see, for example, Patent Document 1).
Method 2:
Connect the common mode reactor to the power line (common mode reactor).
By this method, conduction noise of current components called common mode current can be reduced.
Method 3:
Connect the reactor to the ground wire (ground wire reactor).
According to this method, the conduction noise of a current component called a common mode current can be reduced as in the method 2 (see, for example, Patent Document 2).
Method 4:
Wind a power line and a ground line around a magnetic material with a through hole (leakage current reactor).
By this method, a current component (referred to as leakage current) flowing in one direction through all phases of the power line and the ground line can be reduced (see, for example, Patent Document 3).

Further, the normal mode current output from the power converter is generally overwhelmingly larger than the common mode current and leakage current. Therefore, the normal mode reactor is more susceptible to magnetic saturation than the common mode reactor or the reactor for leakage current.
Therefore, conventionally, a normal mode reactor that conforms to a normal mode current, a common mode reactor that conforms to a common mode current, and a reactor that conforms to a leakage current are individually created.
On the other hand, a method combining two of the methods 1 to 3 has also been proposed. In addition, the reactor which has the function of the method 1 and the method 2 is shown by patent document 4, for example, and the reactor which has the function of the method 2 and method 4 is shown by patent document 5, for example.

JP 2007-135280 A JP 2008-98945 A JP 2001-86734 A JP 2009-135271 A JP 2003-348818 A

By combining the above methods, a high noise suppression effect can be obtained. However, in this case, since the plurality of reactors are used in combination, there arises a problem that the arrangement space, the number of parts, and the cost increase.
Then, the subject of this invention is providing the reactor with the high noise suppression effect which has all the functions of the said methods 1-4 together, without accompanying arrangement space, the number of parts, and an increase in cost, and this reactor was used. It is to provide a noise filter.

  In order to solve the above problems, a reactor according to the present invention includes a core having a gap, and a single-phase or multi-phase power line and a ground line arranged so as to form a magnetic path in the core. The core gap is generated by the normal mode current of the power line so that the core functions as a closed magnetic circuit core for at least one magnetic path generated by the common mode current of the power line. For at least one magnetic path, the core is a closed magnetic circuit core for at least one magnetic path generated by the current of the ground line so that the core functions as an open magnetic circuit core. So that the core functions as a closed magnetic circuit core for at least one magnetic path generated by a current (referred to as leakage current) flowing in one direction through the power line and the ground line. Formed.

The core includes a loop-shaped first member and a second member interposed between opposing sides of the first member in a form in which the gap is formed between the first member, And a third member interposed between opposing sides of the first member in a form in which the gap is not formed between the first member and the first member.
In this case, at least one of the second member and the third member may be formed separately from a magnetic material different from the magnetic material constituting the first member.

A spacer for increasing the structural stability can be fitted into the gap of the core.
The power line and the ground line can be formed by bus bars. The power line and the ground line can be printed on a printed board.
The number of turns of the single-phase or multiphase power line and the number of turns of the ground line are set to 1 or more.

  The reactor of this invention is interposed between the power converter device and the load driven by the output of this power converter device, or between the said power converter device and a system | strain, for example.

  The reactor of the present invention uses a terminal block for electronic equipment having a conductor terminal plate for input / output wiring connection to which the single-phase or multi-phase power line and ground line are connected, and the core is used as the conductor terminal plate. It can also be configured by combining.

  The present invention also provides a noise filter configured using the reactor.

  Since the reactor according to the present invention has the functions of a normal mode reactor, a common mode reactor, a ground wire reactor, and a leakage current reactor, the reactors for obtaining those functions are used in combination. As a result, the arrangement space, the number of parts, and the cost can be reduced. The noise filter according to the present invention can provide the same advantages.

It is a perspective view showing an embodiment of a reactor concerning the present invention. It is sectional drawing which shows the effect | action as a normal mode reactor of the reactor of FIG. It is sectional drawing which shows the effect | action as a common mode reactor of the reactor of FIG. 1, and a grounding line reactor. It is sectional drawing which shows the effect | action as a leakage current reactor of the reactor of FIG. It is sectional drawing which shows embodiment using two types of core materials. It is a perspective view which shows embodiment using the core from which a shape differs. It is a circuit diagram which shows the usage example of the reactor which concerns on this invention. It is a perspective view which shows embodiment of 1 turn structure for three phases. It is sectional drawing which shows the effect | action as a normal mode reactor of the reactor of FIG. It is sectional drawing which shows the effect | action as a common mode reactor of the reactor of FIG. 8, and a grounding line reactor. It is sectional drawing which shows the effect | action as a leakage current reactor of the reactor of FIG. It is a perspective view which shows embodiment of the multiple turn structure for single phases. It is sectional drawing which shows the effect | action as a normal mode reactor of the reactor of FIG. It is sectional drawing which shows the effect | action as a common mode reactor of the reactor of FIG. 12, and a grounding line reactor. It is sectional drawing which shows the effect | action as a leakage current reactor of the reactor of FIG. It is the circuit diagram which showed the structural example of the noise filter which concerns on this invention. Embodiment of the reactor based on this invention comprised in the terminal block is shown, (a) is the top view, (b) is AA sectional drawing of (a).

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Although the reactor according to the present invention does not limit the number of turns, the structure is different between the case of one turn and the case of multiple turns, so each case will be described. In addition, since there is no restriction on the number of phases, the case of single phase and three phases will be described.

First embodiment (in the case of one turn -single phase)
Configuration FIG. 1 shows a reactor 1-1 according to the first embodiment. The reactor 1-1 has a configuration in which a single-phase wiring 3 is passed through a core 2-1.
The core 2-1 includes a square loop portion 21 and leg portions 22 and 23 extending from the lower side to the upper side of the loop portion 21, respectively. The leg portion 22 is formed such that a gap 24 is interposed between the tip thereof and the upper side of the loop portion, and the leg portion 23 is formed so as to reach the upper side from the lower side of the loop portion.
The wiring 3 has a U-phase power line 3 (U), a V-phase power line 3 (V), and a ground line 3 (E). The U-phase power line 3 (U) is formed in the space formed between the left side of the loop portion 21 and the leg 22, and the V-phase power line 3 (V) is formed between the legs 22 and 23. The ground wire 3 (E) is inserted into the space portion formed between the leg portion 23 and the right side of the loop portion 21.

-Action Next, the action of the reactor 1 will be described with reference to FIGS. 2 to 5, the (·) mark and the (×) mark indicate the directions of currents flowing through the U-phase power line 3 (U), the V-phase power line 3 (V), and the ground line 3 (E). Moreover, the arrow in the core 2-1 represents a magnetic path formed by the current.

<Operation as a normal mode reactor>
FIG. 2 shows a magnetic path 5 generated by a normal mode current flowing in the U-phase power line 3 (U) and a magnetic path 6 generated by a normal mode current flowing in the V-phase power line 3 (V). In the magnetic paths 5 and 6, a gap 24 provided in the core 2-1 is interposed. Therefore, the reactor 1-1 according to the present embodiment including the gap 24 acts as a reactor with a gap in the function of the normal mode reactor.
As is well known, the normal mode current is overwhelmingly larger than the common mode current, the current flowing through the ground line 3 (E), and the leakage current. Therefore, the magnetic field generated by the core 2-1 based on the normal mode current is considerably larger than that based on the common mode current. However, as described above, the reactor 1 according to the present embodiment functions as a reactor with a gap in the normal mode in which the generated magnetic field is large. Therefore, the magnetic saturation of the core 2-1 can be suppressed by the gap 24.

<Operation as a common mode reactor>
FIG. 3 shows a magnetic path 7 generated by a common mode current flowing in the U-phase power line 3 (U) and the V-phase power line 3 (V), and a magnetic path 8 generated by a current flowing in the ground line 3 (E). Indicates. The gap 24 is not interposed in the magnetic paths 7 and 8. Therefore, the reactor 1 according to the present embodiment acts as a gapless reactor in the function of the common mode reactor.

<Operation as grounding reactor>
The gap 24 is not interposed in the magnetic path 8 generated by the current flowing through the ground line 3 (E) shown in FIG. Therefore, the reactor 1 according to the present embodiment acts as a gapless reactor in the function of the grounding line reactor.

<Operation as a leakage current reactor>
FIG. 4 shows a magnetic path 9 generated by a common mode current flowing through U-phase power line 3 (U), V-phase power line 3 (V), and ground line 3 (E). The gap 24 is not interposed in the magnetic path 9. Therefore, the reactor 1 according to the present embodiment acts as a gapless reactor in the function as a leakage current reactor.

Next, a modification of the first embodiment will be described.
"Modification 1"
A spacer (not shown) made of a nonmagnetic material is fitted into the gap 24 shown in FIGS. If this spacer is used, the structure of the core 2-1 can be stabilized and the performance can be improved.

"Modification 2"
Instead of the core 2-1 shown in FIGS. 1 to 4, a core 2-2 as shown in FIG. 5 may be used.
The core 2-2 has a configuration in which the leg portion 23 of the core 2-1 is replaced with a leg portion 25. The leg portion 25 is formed of a magnetic material (for example, Mn—Zn ferrite) different from the magnetic material (for example, Ni—Zn ferrite) constituting the loop portion 21. Note that the upper and lower end surfaces of the leg portion 25 are in close contact with the inner side surface of the loop portion 21.
According to the reactor 1-2 according to the second modification, it is possible to increase the degree of freedom in designing the reactance with respect to the common mode current flowing through the power lines 3 (U) and 3 (V) and the current flowing through the ground line 3 (E). .
Contrary to the above, the leg portion 22 shown in FIGS. 1 to 4 is formed of a magnetic material different from the magnetic material constituting the loop portion 21, or the leg portions 22 and 23 shown in FIG. Both of them can be formed of a magnetic material different from the magnetic material constituting the loop portion 21. In the latter case, the materials of the leg portions 22 and 23 may be different from each other.

“Modification 3”
The shape of the core is not limited to the shape of the core 2-1 shown in FIG. 1 as long as it satisfies the technical scope of claim 1. For example, the shape as shown in FIG. 6 may be used.
A core 2-3 shown in FIG. 6 includes a loop portion 21 ′ and a leg portion 23 ′ corresponding to the loop portion 21 and the leg portion 23 shown in FIG. A leg portion 22 'extending toward the end, and a gap 24' is formed between the tip of the leg portion 22 'and the leg portion 23'.
In the reactor 1-3 according to the modified example 3 using the core 2-3 as described above, as illustrated, the power line 3 (U) is formed between the lower side of the loop portion 21 ′ and the leg portion 22 ′. In the space, the power line 3 (V) is formed between the leg 22 'and the upper side of the loop part 21', and the grounding wire 3 (E) is provided between the leg 23 'and the right side of the loop part 21'. Each is inserted through the formed space.

As described above, the reactor 1-1 according to the first embodiment and the reactors according to the first to third modifications thereof have a function as a normal mode reactor, a function as a common mode reactor, a function as a ground wire reactor, and It also functions as a leakage current reactor (radiation noise reactor).
Therefore, for example, by inserting this reactor between the power conversion device 26 such as an inverter shown in FIG. 7 and the load (motor) 27 or between the power conversion device 26 and a system (not shown), It is possible to obtain the same noise attenuation effect as when a plurality of individual reactors shown in FIG. This is advantageous in reducing the arrangement space, the number of parts, and the cost.

As described above, in implementing the present invention, there is no restriction on the number of phases of power to be applied. Therefore, a second embodiment having a different number of phases from the first embodiment will be described.
Second embodiment (in the case of one turn -three-phase-)
Configuration FIG. 8 shows a reactor 10 according to the second embodiment. The reactor 10 has a configuration in which a three-phase wiring 30 is passed through a core 20.
The core 20 has a square loop portion 210 and legs 220, 220 ′, and 230 that extend from the lower side to the upper side of the loop portion 210, respectively. The leg portions 220 and 220 ′ are formed such that gaps 240 and 240 ′ are interposed between their tips and the upper side of the loop portion 210, respectively, and the leg portion 230 extends from the lower side to the upper side of the loop portion 210. It is formed to reach.
Wiring 30 has U-phase power line 30 (U), V-phase power line 30 (V), and ground line 30 (E). The U-phase power line 30 (U) is formed in the space formed between the left side of the loop part 210 and the leg 220, and the V-phase power line 30 (V) is formed between the legs 220 and 220 ′. In the space portion, the W-phase power line 30 (W) is formed in the space portion formed between the leg portions 220 ′ and 230, and the grounding wire 30 (E) is formed between the leg portion 230 and the right side of the loop portion 21. Each space is inserted.

-Action Although the number of phases is different, the action is equivalent in principle to the reactor 1 of FIG. 1 according to the single-phase embodiment.
<Operation as a normal mode reactor>
In FIG. 9, the magnetic path 11 generated by the normal mode current flowing in the U-phase power line 30 (U), the magnetic path 12 generated by the normal mode current flowing in the V-phase power line 30 (V), and the V-phase power line 30 The magnetic path 13 produced | generated by the normal mode electric current which flows into (V) is shown. A gap 240 is interposed in the magnetic path 11, gaps 240 and 240 ′ are interposed in the magnetic path 12, and a gap 240 ′ is interposed in the magnetic path 13. Therefore, this reactor 10 acts as a reactor with a gap in the function of the normal mode reactor.

<Operation as a common mode reactor>
FIG. 10 shows a magnetic path 14 generated by the common mode current flowing in the U-phase power line 30 (U), the V-phase power line 30 (V), and the W-phase power line 30 (W), and a current flowing in the ground line 3 (E). Shows a magnetic path 15 generated by. There are no gaps 240 and 240 ′ in the magnetic paths 14 and 15. Therefore, this reactor 10 acts as a reactor without a gap in the function of the common mode reactor.

<Operation as grounding reactor>
In the magnetic path 15 generated by the current flowing through the ground line 30 (E) shown in FIG. 10, no gaps 240 and 240 ′ are interposed. Therefore, this reactor 10 acts as a reactor without a gap in the function of the grounding line reactor.

<Operation as a leakage current reactor>
FIG. 11 shows the magnetic path 16 generated by the common mode current flowing in the U-phase power line 30 (U), the V-phase power line 30 (V), the W-phase power line 30 (W), and the ground line (E). There are no gaps 240, 240 ′ in the magnetic path 16. Therefore, this reactor 10 acts as a reactor without a gap in the function as a leakage current reactor.
In addition, the structure of the modifications 1-3 applied to the reactor 1-1 which concerns on the said 1st Embodiment is applicable also to the said reactor 10. FIG.
The reactor 10 can also be used for the application shown in FIG. 7 (however, it is interposed between a three-phase power converter and a three-phase load).

As described above, in implementing the present invention, there is no restriction on the number of turns of the wiring. Therefore, a third embodiment in which the number of wiring turns is different from that of the first embodiment will be described.
Third embodiment (in the case of multiple turns)
Configuration As shown in FIG. 12, the reactor 1-1 ′ according to the third embodiment includes the U-phase power line 3 (U) and the V-phase power line 3 (V ) And the ground wire 3 (E) are each wound by a plurality of turns, and is different from the embodiment shown in FIG.

-Action Although the number of turns of the wiring 3 is different, the action is equivalent in principle to the reactor 1 of FIG.
<Operation as a normal mode reactor>
As shown in FIG. 13, magnetic paths 5 ′ and 6 ′ corresponding to the magnetic paths 5 and 6 shown in FIG. 2 are formed. Therefore, the normal mode reactor functions as a reactor with a gap.
<Operation as a common mode reactor>
As shown in FIG. 14, magnetic paths 7 ′ and 8 ′ corresponding to the magnetic paths 7 and 8 shown in FIG. 3 are formed. Therefore, the common mode reactor functions as a gapless reactor.
<Operation as grounding reactor>
There is no gap 24 in the magnetic path 8 'shown in FIG. Therefore, it functions as a reactor without a gap in the function of the ground wire reactor.
<Operation as a leakage current reactor>
As shown in FIG. 15, a magnetic path 9 ′ corresponding to the magnetic path 9 shown in FIG. 4 is formed. Therefore, in the function as a leakage current reactor, it acts as a reactor without a gap.
In addition, also in the said reactor 1-1 'of a multiturn structure, the structure of the modifications 1-3 applied to the reactor 1-1 which concerns on the said 1st Embodiment is applicable. Further, the reactor 1-1 ′ can also be used for the application shown in FIG. And the said multi-turn structure is applicable also to the reactor 10 for multiphases shown in FIG.

FIG. 16 shows a configuration example of the noise filter 28 using any one of the reactors 1-1 to 1-3 and 1-1 ′.
The noise filter 28 includes the single-phase reactor (1-1 to 1-3, 1-1 ′) interposed between the power converter 26 and the load (motor) 27, and the output wiring of the power converter 26. It has a configuration in which a line capacitor (line capacity) 29 interposed therebetween is combined, and noise included in the wiring between the power converter 26 and the load 27 is removed.
According to the noise filter 28, it is possible to reduce the arrangement space, the number of parts, and the cost.
In addition, when the thing of a multiphase specification is used for the power converter device 26 and the load 27, the reactor 10 for multiphases shown in FIG. 8 is the said single-phase reactor (1-1 to 1-3, 1-1. Applies instead of ').

FIG. 17 shows the terminal block 17 constituting the three-phase reactor 10 of FIG. As shown in FIG. 17 (a), the terminal block 17 includes an insulating base 17a, four conductor terminal plates 17b arranged in the longitudinal direction of the insulating base 17a, and as shown in FIG. 17 (b). And a core 20 through which each conductor terminal plate 17b is inserted.
Each conductor terminal plate 17b has one end connected to external wiring (three-phase power line and ground line) and the other end connected to corresponding wiring (three-phase power line and ground line). Therefore, each conductor terminal board 17b is a conductor corresponding to the power line and ground line of each phase, and constitutes reactor 10 shown in FIG.
According to this terminal block 17, it is not necessary to attach the wiring to the core 20, so that the installation man-hours and installation time can be reduced. In addition, it is possible to reduce the size of the device and to prevent damage during manufacture, transportation, or actual use.
In addition, you may provide the insulating film which is not illustrated in the part in which the conductor terminal board 17b and the core 20 of this terminal block 17 adjoin. Although this terminal block 17 constitutes the multiphase reactor 10, the terminal block constituting the single-phase reactor described above can be formed in the same manner.

The present invention is not limited to the above embodiments, and includes various modifications.
That is, in the above embodiment, cables are used as the wirings 3 and 30, but the wirings 3 and 30 may be constituted by bus bars, for example. The wirings 3 and 30 can also be formed of a metal foil on a printed board. Furthermore, in each of the above-described embodiments, a configuration in which a core, a core E, a core I, or the like is combined as a core may be applied.

1-1 to 1-3, 1-1 ′, 10 reactors 2-1 to 2-3, 20 cores 21, 21 ′, 210 loop portions 24, 24 ′, 240, 240 ′ gaps 22, 22 ′, 23, 25, 220, 220 ', 230 Leg 3, 30 Wiring 17 Terminal block 17a Insulation base 17b Conductor terminal plate 26 Power converter 27 Load 28 Noise filter 29 Line capacitor

Claims (10)

A reactor comprising a core formed with a gap, and a single-phase or multi-phase power line and a ground line arranged to form a magnetic path in the core, wherein the gap of the core is
For at least one magnetic path generated by the common mode current of the power line, at least one magnetic path generated by the normal mode current of the power line so that the core functions as a closed magnetic path core. On the other hand, for at least one magnetic path generated by the current of the ground line, the core functions as a closed magnetic circuit core so that the core functions as an open magnetic circuit core. In addition, for at least one magnetic path generated by a current (referred to as leakage current) flowing in one direction through the power line and the ground line, the core is formed so as to function as a closed magnetic path core. Reactor characterized by. The core is
A loop-shaped first member;
A second member interposed between opposing sides of the first member in a form in which the gap is formed between the first member;
A third member interposed between opposing sides of the first member in a form in which the gap is not formed between the first member and the first member;
The reactor according to claim 1, comprising:   The at least one of the second member and the third member is formed separately from a magnetic material that is different from the magnetic material constituting the first member. Reactor.   The reactor according to claim 1, wherein a spacer is fitted in the gap.   The reactor according to claim 1, wherein the power line and the ground line are formed of bus bars.   The reactor according to claim 1, wherein the power line and the ground line are printed on a printed circuit board.   The reactor according to claim 1, wherein the number of turns of the single-phase or multiphase power line and the number of turns of the ground line are one or more.   The reactor according to claim 1, wherein the reactor is interposed between a power converter and a load driven by an output of the power converter or between the power converter and a system.   Using a terminal block for electronic equipment provided with a conductor terminal plate for connection of input / output wiring to which the single-phase or multi-phase power line and ground line are connected, and combining the core with the conductor terminal plate The reactor according to claim 1.   A noise filter comprising the reactor according to claim 1.

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