JP2005045133A - Electromagnetic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic device in which the structure of a magnetic circuit and the wound structure of coils are simple, in which the inductance is variable, and which can be produced easily at a low cost to connect with a power system in series. <P>SOLUTION: The electromagnetic device has a magnetic core symmetrically forming a two-by-two-matrix-shaped magnetic path in a four closed magnetic path, a main flux passes a first straight line magnetic path of a cross-shaped magnetic path in the two-by-two-matrix-shaped magnetic path, AC main windings 1a, 1b are wound so as to circulate the four closed magnetic paths opposed symmetrically to each other at a cross-shaped intersection, DC control windings 2a, 2b, 2c, 2d are wound so that a control flux passes the second straight line magnetic path of the cross-shaped magnetic path in one direction to circulate two magnetic paths symmetrically, and the magnetic resistance of the common magnetic path of the main flux and the control flux is adjusted by control of the control magnetic flux. The magnetic core forming the two-by-two-matrix-shaped magnetic path is divided at the center of the second straight line magnetic path of the cross-shaped magnetic path, and the two-by-two-matrix-shaped magnetic path is divided in the manner of the magnetic circuit with a gap 7. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electromagnetic device that can reduce harmonic distortion and vary reactance without being affected by an excitation current of a main winding, and further relates to an electromagnetic device that can be connected in series to a power system.

  As a conventional technique that can reduce harmonic distortion, change reactance, and can be connected in series to the power system without being affected by the excitation current of the main winding, the electromagnetic device previously proposed by the applicant ( There exists patent document 1).

  FIG. 8 is a connection diagram for explaining an example of the electromagnetic device (Patent Document 1) previously proposed by the present applicant. In this electromagnetic device, a first main winding 31a, a second main winding 31b, and control windings 32a, 32b, 32c, and 32d are wound around a U-shaped magnetic core 33, and an open terminal of a control winding connected in series. The control circuit 34 is connected to the side.

When an AC power source is connected to the open end of the main winding and a DC control current Ic is passed through the control winding, the product of the number of turns of the control winding and the DC control current Ic in the control windings 32a, 32b, 32c, and 32d. When the magnetomotive force represented is generated, the magnetic flux density in the common magnetic path portion in which the control magnetic fluxes φc31 and φc32 and the main magnetic fluxes φ31a, φ31a ′, φ31b, and φ31b ′ are in the same direction increases, and the permeability changes. The main magnetic flux is controlled and the reactance is lowered.
JP 2003-068539 A

  As a general method of manufacturing an electromagnetic device using the above-described magnetic field-shaped magnetic core as a power electromagnetic device, two E-type magnetic cores 41, 42 and one as shown in FIG. The I-type magnetic core 43 is abutted and manufactured as shown in FIG. 9B. In this case, the magnetic core is different from the conventional standard EI-type magnetic core, and the width of the I-type magnetic core 43 (2t). ) Is about twice the width (t) of the standard E-type magnetic core 41, so that a low-cost standard EI type magnetic core could not be applied.

  In view of the above circumstances, the present invention has a simple magnetic circuit structure and a winding structure for windings, and can easily and lowly manufacture an electromagnetic device that can vary the inductance and can be connected in series to a power system. The issue is to provide costs.

  Symmetrically, it has a magnetic core that forms a U-shaped magnetic path with four closed magnetic paths, and the main magnetic flux passes through the first straight magnetic path of the cross-shaped magnetic path in the U-shaped magnetic path, The AC main winding is wound so as to circulate through the four closed magnetic paths symmetrically facing each other at the intersection, and the control magnetic flux passes through the second linear magnetic path of the cruciform magnetic path in one direction symmetrically. An electromagnetic device in which a DC control winding is wound so as to recirculate two magnetic paths, and the magnetic resistance of the common magnetic path of the main magnetic flux and the control magnetic flux is adjusted by controlling the control magnetic flux. The magnetic core forming the magnetic path is divided at the center of the second linear magnetic path of the cross-shaped magnetic path, and the U-shaped magnetic path is divided with a gap in the magnetic circuit. is there.

  According to the present invention, an electromagnetic device that has a simple magnetic circuit structure and winding winding structure, suppresses a harmonic current regardless of the presence or absence of a load current, and varies a reactance over a wide range without providing a tap. Can be realized easily and at low cost, and with the recent increase in power demand and diversification of loads, it is possible to provide flexible power equipment that can cope with diversification of loads such as system voltage fluctuations. This contributes to stabilization of the voltage of the power system.

  Considering the U-shaped magnetic path shown in FIG. 8, the main magnetic fluxes Φ31a, Φ31a ′ and Φ31b, Φ31b ′ are opposed to each other, and electromagnetic waves are The physical structure of the iron core and the magnetic circuit including the flow of magnetic flux are symmetrical. Further, the flow of magnetic flux in the horizontal magnetic path portion is in principle parallel to the longitudinal direction of the iron core constituting the horizontal magnetic path.

  Therefore, with respect to the magnetic flux of the horizontal magnetic path of this magnetic circuit, the upper magnetic flux of the main winding 31a and the control windings 32a and 32b constituting the upper part of the U-shaped magnetic path and the upper magnetic flux of φ31a, φ31a ′, φc31, and the lower part thereof Focusing on the lower magnetic flux φ31b, φ31b ′, φc32 by the main winding 31b and the control windings 32c, 32d constituting the magnetic flux, the two magnetic fluxes are basically symmetrical because the iron core structure and the magnetic circuit configuration are symmetrical. The values are the same, and both magnetic fluxes pass through magnetic paths close to each other and are considered to be affected by the same influence and interference.

  Based on the above consideration, as shown in FIG. 1, when considering the state in which the iron core constituting the horizontal magnetic path of the rice field-shaped magnetic path is divided in a horizontal plane, this divided field-shaped magnetic path is divided into planes. The physical structure of the electromagnetic core and the magnetic circuit including the flow of magnetic flux are symmetric with respect to the upper horizontal axis, and are the same as the original rice field-shaped magnetic path.

  Further, considering the magnetic flux of the horizontal magnetic path portion, the upper side of the divided horizontal magnetic path portion is the upper magnetic flux φ1a, φ1a ′, φc1, and the lower side is the lower magnetic flux φ1b, φ1b ′, φc2 on the divided surface. It is considered that the magnetic flux leaking into the formed gap 7 is affected and interfered with it.

  That is, if the relationship between the influence of the upper magnetic flux and the lower magnetic flux through the gap 7 and the relationship between the interference and reactance control characteristics can be confirmed, for example, as shown in FIG. An electromagnetic device having a U-shaped magnetic path can be configured easily.

  FIG. 1 is an example in which an electromagnetic device according to the present invention is configured by using a conventionally used EI iron core. A rice field-shaped magnetic core includes a first E-type magnetic core 4a and a first I-type magnetic core 5a. A tripod magnetic core configured such that two iron core window portions are formed, a second E-type magnetic core 4b and a second I-type magnetic core 5b, and a tripod magnetic core configured so that two iron core window portions are formed. The magnetic paths are opposed to each other through a gap 7 so that the magnetic path is in the shape of a rice field, the joint surface of the first E-type magnetic core 4a and the I-type magnetic core 5a, and the second E-type magnetic core 4b and the second I-type. The joint surface of the magnetic core 5b is formed by abutting each laminated steel plate constituting the magnetic core so as to be parallel.

  The first main winding 1a is wound around the center leg of the first E-type magnetic core 4a, and the second main winding 1b is wound around the center leg of the second E-type magnetic core 4b. The main windings 1a and 1b are connected in series so that the magnetic fluxes φ1a and φ1b generated from both main windings are in the same direction toward the I-type magnetic cores 5a and 5b.

  The control windings 2a and 2b are wound around the outer leg of the first E-type magnetic core 4a, and the control windings 2c and 2d are wound around the outer leg of the second E-type magnetic core 4b. All control windings are connected in series so that the induced voltages generated in the control windings 2a and 2b, 2c and 2d are canceled, and the control circuit 6 is connected to the open terminal side.

  As for the control winding, one set of 2a, 2b, 2c, and 2d is connected so that the induced voltage generated is cancelled, and the other set of 2 windings connected in the same manner. Can be connected in series or in parallel, and the control circuit 6 can be connected to the open terminal side.

  Further, a method for constructing a tripod magnetic core constituted by a first E-type magnetic core 4a and a first I-type magnetic core 5a, and a tripod magnetic core constituted by a second E-type magnetic core 4b and a second I-type magnetic core 5b is as follows. It is clear that the same function can be realized even if the vertical relationship between the type magnetic core and the I type magnetic core is reversed, and the main point is that the upper and lower closed magnetic paths are formed symmetrically.

  In FIG. 1, it is assumed that an AC power source is connected to the open end of the main winding and a current IL1 in the direction indicated by the arrow flows. When current IL1 is a positive cycle, current IL2 flows in a negative cycle. When the current IL1 flows, main magnetic flux φ1a and main magnetic flux φ1a ′ generated by the main winding 1a and main magnetic flux φ1b and main magnetic flux φ1b ′ generated by the main winding 1b are generated in the magnetic paths, respectively. On the contrary, when the current IL2 flows, a main magnetic flux in the opposite direction to that described above is generated.

  The generated main magnetic flux passes through four closed magnetic paths when the DC control current Ic is not passed through the control winding, and reactance corresponding to the number of turns and the magnetic resistance of the iron core is generated in the main winding. The iron core portion and the I-type magnetic core portion around which the control winding is wound serve as a common magnetic path for the control magnetic flux φc and the main magnetic flux.

  When the DC control current Ic is supplied to the control winding while the currents IL1 and IL2 are supplied to the main winding, the product of the number of turns of the control winding and the DC control current Ic in the control windings 2a, 2b, 2c, and 2d. When the magnetomotive force represented is generated, the magnetic flux density of the common magnetic path portion in which the control magnetic fluxes φc1 and φc2 and the main magnetic fluxes φ1a, φ1a ′, φ1b, and φ1b ′ are in the same direction increases, and the permeability changes. The main magnetic flux is controlled and the reactance is lowered.

  When the common magnetic path approaches a magnetic saturation state by increasing the main winding currents IL1 and IL2 or the DC control current Ic, the main magnetic flux generated from the main windings 1a and 1b becomes the same toward the I-type magnetic cores 5a and 5b. Since the main windings are divided and connected so as to be in the direction, the increasing main magnetic flux φ1a and main magnetic flux φ1a ′, and the increasing main magnetic flux φ1b and main magnetic flux φ1b ′ are offset through the gap 7 . Since the increase in the main magnetic flux caused by the pair of main windings 1a and 1b does not circulate in the closed magnetic circuit, the magnetomotive force of the main windings cancels each other.

  Further, even if the main winding currents IL1 and IL2 increase, the main magnetic flux generated by the main winding 1a and the main magnetic flux generated by the main winding 1b are separated by a gap 7 so that the common magnetic path is maintained at a constant magnetic flux density. Therefore, the main magnetic flux can be controlled by controlling the DC control current Ic, and the reactance can be varied. That is, regardless of the main winding current, the reactance can be varied by passing the DC control current Ic through the control winding.

  Further, by making the I-type magnetic cores 5a and 5b have the same configuration, the magnetic potentials between the I-type magnetic cores 5a and 5b by the main magnetic fluxes φ1a and φ1b, the main magnetic fluxes φ1a ′ and φ1b ′, and the control magnetic fluxes φc1 and φc2 are the same. Therefore, no electromagnetic force is applied to the gap, no increase in noise, etc., and the gap can be easily created with a film or the like.

  Even if the gap 7 is provided, the main magnetic fluxes φ1a, φ1a ′ and the control magnetic flux φc1 return through the I-type magnetic core 5a, and the main magnetic flux φ1b, φ1b ′ and the control magnetic flux φc2 pass through the I-type magnetic core 5b. Therefore, since the magnetic resistance of the magnetic circuit corresponding to each magnetic flux by providing the gap 7 does not increase, the influence of the gap on the reactance control characteristics is small.

  FIG. 2A shows an example of reactance control characteristics according to the present invention. The vertical axis represents the reactance, and the horizontal axis represents the control current Ic. By increasing the direct current control current Ic, it is possible to vary substantially the same reactance even if a gap is provided.

FIG. 2B shows an example of the harmonic distortion rate characteristic of the excitation current when a voltage is applied to the electromagnetic device according to the present invention. The vertical axis represents the harmonic distortion rate, and the horizontal axis represents the control current Ic. Represents.
Even if the gap is provided, the harmonic distortion rate characteristic is not deteriorated, but rather the harmonic distortion rate is lowered. In the case where there is no gap, the common magnetic path portion is composed only of a non-linear magnetic circuit such as iron, but by providing a gap, a part of the common magnetic path is a highly linear space magnetism. This is because the non-linearity is improved because the circuit becomes a parallel circuit of a non-linear magnetic circuit such as iron.

  As described above, according to the present invention, the magnetic core portion composed of the E-type magnetic core 4a and the I-type magnetic core 5a around which the main winding 1a and the control windings 2a and 2b are wound, the main winding 1b and the control winding. It is possible to separately manufacture the magnetic core portion composed of the E-type magnetic core 4b and the I-type magnetic core 5b around which the wires 2c and 2d are wound, and the structure of the magnetic circuit and the winding structure of the winding are simple. Production of an electromagnetic device capable of continuously changing the reactance at high speed without being affected by the main winding current can be realized easily and at low cost. In FIG. 1, the explanation of the electromagnetic device is shown by an example including an E-type magnetic core and an I-type magnetic core.

  FIG. 3 shows an example in which an electromagnetic device is configured by enlarging the gap 7 with respect to two sets of tripod cores provided with the gap 7. The main winding 1a is wound around the central leg and the control winding is wound around the outer leg. The first tripod magnetic core 3a wound with the wires 2a and 2b and the second tripod magnetic core 3b wound with the main winding 1b around the center leg and the control windings 2c and 2d around the outer leg are spatially arranged. They are arranged symmetrically.

  In the tripod magnetic cores 3a and 3b, the directions of the main magnetic fluxes φ1a and φ1a ′ by the main winding 1a of the tripod magnetic core 3a and the directions of the main magnetic fluxes φ1b and φ1b ′ by the main winding 1b of the tripod magnetic core 3b are symmetrical to each other. Both tripod magnetic cores are arranged adjacent to each other so that leakage magnetic fluxes generated by the main windings 1a and 1b generated when the magnetic path is in a magnetic saturation state interfere with each other.

  The main windings 1a and 1b are connected in series so that the induced voltages generated in the control windings 2a and 2b are canceled by the main magnetic fluxes φ1a and φ1a ′ by the main winding 1a, respectively, and the main magnetic flux by the main winding 1b All control windings are connected in series so that the induced voltages generated in the control windings 2c and 2d are canceled by φ1b and φ1b ′, and the control circuit 6 is connected to the open terminal side.

  Note that the control winding is connected in series or in parallel with one set of the connected windings so that the induced voltage generated is cancelled, and the remaining two windings connected in the same manner, and the control circuit 6 is provided on the open terminal side. It can also be connected.

The main magnetic flux generated in the tripod core passes through the respective closed magnetic paths when no DC control current is passed through the control winding, and reactance according to the number of turns and the magnetic resistance of the iron core is generated in the main winding.
When a DC control current Ic is passed through the control winding, a magnetomotive force is generated as described above, so that the control magnetic fluxes φc1 and φc2 and the main magnetic fluxes φ1a, φ1a ′, φ1b, and φ1b ′ are in the same direction. The magnetic flux density of the portion increases, the permeability changes, the main magnetic flux is controlled, and the reactance decreases.

  When the common magnetic path approaches a magnetic saturation state by increasing the main winding current or the DC control current, the increasing main magnetic fluxes φ1a and φ1a ′ and the increasing main magnetic fluxes φ1b and φ1b ′ become two leakage fluxes. They cancel each other through the space between the pair of tripod cores. For this reason, the main magnetic flux can be controlled by controlling the DC control current Ic, and the reactance can be varied. That is, regardless of the main winding current, the reactance can be varied by passing the DC control current Ic through the control winding.

  As shown in FIG. 3, as a method of arranging two sets of tripod magnetic cores, a method of arranging up and down with respect to the axis of symmetry has been shown. However, if the spatial arrangement is such that leakage flux interferes, both tripods Various arrangement methods such as arranging magnetic cores in parallel are possible.

FIG. 4A shows an example of the control characteristic of reactance when both tripod magnetic cores are juxtaposed, and the reactance substantially equivalent to that without a conventional gap can be varied.
FIG. 4B similarly shows an example of the harmonic distortion rate characteristic, and although the harmonic distortion rate is slightly deteriorated, almost the same harmonic distortion rate is obtained.

  As described above, it is important that the leakage fluxes generated from the two sets of tripod cores are adjacent to each other so that the leakage fluxes interfere with each other. Electromagnetic devices with excellent characteristics can be realized.

  Even when two sets of tripod magnetic cores are arranged symmetrically, the interference degree of leakage flux is affected by the distance between both magnetic cores, so increasing the distance between the magnetic cores reduces the degree of interference and the rate of change in reactance. Will decline.

  FIG. 5 shows a tripod formed by opposing a first E-type cut core 10a and a second E-type cut core 10b in which a main winding 1a is wound around a central leg and control windings 2a and 2b are wound around an outer leg. A tripod magnetic core formed by opposing a magnetic core and a third E-shaped cut core 10c and a fourth E-shaped cut core 10d in which the main winding 1b is wound around the center leg and the control windings 2c and 2d are wound around the outer leg. The two sets of tripod magnetic cores are arranged so as to be in contact with each other through the gap 7 so as to face each other so that the magnetic path has a square shape.

  According to this configuration, since an E-shaped cut core to which a high magnetic flux density steel plate is applied can be used, the core design magnetic flux density can be increased, the device can be made compact, and a low-cost electromagnetic device can be realized. be able to.

(Application example)
FIG. 6 is a diagram showing an application example of the electromagnetic device of the present invention to the reactive power compensator, in which the electromagnetic device 11 and the power capacitor 12 are connected in parallel, inserted in parallel to the transmission line, and controlled by the electromagnetic device. The reactive power from the slow phase to the fast phase generated in the system is continuously compensated.

(Application examples)
FIG. 7 is a diagram for explaining an application example in which the electromagnetic device of the present invention is applied to a multi-function transformer. In the electromagnetic device of the present invention shown in FIG. 1, the main windings are primary windings 8a and 8b. Further, the multi-function transformer is configured by winding the secondary windings 9a and 9b on the respective legs around which the primary windings 8a and 8b are wound and connecting them in the same manner as the primary winding.

  In FIG. 7, it is assumed that an AC power source is connected to the primary winding, a load is connected to the secondary winding, and a secondary current IL2 in the direction indicated by the arrow flows in the secondary winding. When no DC control current is passed, the primary current IL1 flows through the primary windings 8a and 8b so as to cancel the magnetic flux generated by the secondary current, and the transformer operation is shown as a whole.

  When the DC control current Ic is passed through the control winding, the magnetic permeability is changed by the generation of a magnetomotive force represented by the product of the number of turns of the control winding and the DC control current Ic, and the main magnetic flux is controlled. As the control current increases, the main magnetic fluxes φ1a and φ1a ′ by the primary winding 8a and the main magnetic fluxes φ1b and φ1b ′ by the temporary winding 8b cancel each other through the gap 7 because they are opposite to each other. As a result, the main magnetic flux interlinking with the primary winding is reduced.

Therefore, the primary winding has an exciting current that is a delayed reactive current that generates the main magnetic flux necessary to maintain the voltage across the terminals of the primary winding in accordance with the decrease in the main magnetic flux accompanying the control of the DC control current. To increase.
That is, in addition to the function as a transformer, it is possible to realize a multi-function transformer capable of adjusting the reactive current flowing into the primary side by adjusting the DC control current.

  In addition, although the multifunctional transformer was demonstrated and applied to the electromagnetic device of Claim 1, it is clear that it can apply also to the other electromagnetic device described by this invention.

It is a connection diagram which shows an example of the basic composition of the single phase type electromagnetic equipment by this invention. It is a figure which shows the example of control characteristics of an electromagnetic device. It is a connection diagram which shows the other basic structural example of the electromagnetic equipment by this invention. It is a figure which shows the example of control characteristics of an electromagnetic device. It is a connection diagram which shows the other basic structural example of the electromagnetic equipment by this invention. It is a connection diagram which shows the example which applied this invention to the reactive power compensation apparatus. It is a connection diagram which shows the example which applied this invention to the multifunctional transformer. It is a connection diagram which shows an example of the electromagnetic equipment previously proposed by the present applicant. It is a figure which shows an example of the manufacturing method of the electromagnetic device previously proposed by the present applicant.

Explanation of symbols

1 (1a, 1b) ... main winding, 2 (2a, 2b, 2c, 2d) ... control winding, 3 (3a, 3b) ... tripod magnetic core, 4 (4a, 4b) ... E type magnetic core, 5 (5a 5b) ... I-type magnetic core, 6 ... control circuit, 7 ... gap, 8 (8a, 8b) ... primary winding, 9 (9a, 9b) ... secondary winding, 10 (10a, 10b, 10c, 10d) ... E-shaped cut core, 11 ... electromagnetic device, 12 ... power capacitor, 31 (31a, 31b) ... main winding, 32 (32a, 32b, 32c, 32d) ... control winding, 33 ... field-shaped magnetic core , 34 ... control circuit, 41, 42 ... E type magnetic core, 43 ... I type magnetic core.

Claims (5)

Symmetrically, it has a magnetic core that forms a U-shaped magnetic path with four closed magnetic paths,
The AC main winding is passed through the first linear magnetic path of the cross-shaped magnetic path in the U-shaped magnetic path, and symmetrically flows back through the four closed magnetic paths facing each other at the intersection of the cross. Wound,
The DC control winding is wound so that the control magnetic flux passes through the second linear magnetic path of the cruciform magnetic path in one direction and returns to the two magnetic paths symmetrically,
An electromagnetic device for adjusting a magnetic resistance of a common magnetic path of a main magnetic flux and a control magnetic flux by controlling the control magnetic flux,
The magnetic core that forms the U-shaped magnetic path is divided at the center of the second linear magnetic path of the cross-shaped magnetic path, and the U-shaped magnetic path is divided with a gap in the magnetic circuit. Characteristic electromagnetic equipment.   2. The electromagnetic device according to claim 1, wherein the magnetic core is configured in a square shape by overlapping two sets of tripod magnetic cores formed of an I-shaped magnetic core and an E-shaped magnetic core.   2. The electromagnetic device according to claim 1, wherein the magnetic core is configured in a square shape by overlapping two sets of tripod magnetic cores each having an E-shaped cut core facing each other.   4. The electromagnetic device according to claim 2, wherein two sets of tripod magnetic cores are overlapped via a gap and configured in a square shape.   4. The electromagnetic device according to claim 2, wherein two sets of tripod magnetic cores to be stacked are juxtaposed.

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