JP2005347535A - Reactor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reactor of low cost and high reliability wherein magnetic core texture is simple, and stable manufacturing technology of a laminated core transformer can be used, in addition to high performance that swinging and noise are small since a block magnetic core is not used, loss by fringing is small, local overheat is little and waveform distortion is small. <P>SOLUTION: In the reactor using a magnetic core, the magnetic core of each phase is constituted of a main magnetic core which makes a closed magnetic circuit or an open magnetic circuit, and a bypass magnetic core which makes a closed magnetic circuit. Around the main magnetic core, a secondary coil is wound to interior, and a primary coil is wound around the exterior in the shape of a concentric circle. The bypass magnetic core is installed in the position of a main air gap which is located in exterior of the secondary coil and interior of the primary coil, and it is constituted so that the secondary coil is short-circuited. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a power reactor or a current-limiting reactor used in an AC power circuit, and more specifically, a reactor that can be made using a laminated core similar to a normal transformer and is inexpensive and suitable for increasing capacity. It is about.

A generally used power reactor is composed of an iron core that is a path for magnetic flux, a coil (winding) wound around the iron core, and an attached structure that fixes them.
For example, referring to FIG. 1, it is a figure explaining the structure of the conventional reactor, (A) is a whole block diagram, (B) is a top view, (C) is an elevation view.

As shown in FIG. 1A, a coil 20 is wound around the iron core 10, and when an AC power supply v is applied, a magnetic flux φ is generated in the iron core 10.
As shown in FIG. 1 (B), in the case of a laminated iron core, the leg portion 11 of the iron core 10 is formed by laminating thin iron plates 14a having different widths (lateral directions in the figure) to form a substantially cylindrical shape as a whole. The coil 20 is installed outside. Although not shown, the lower yoke portion 15 of the iron core 10 is also formed of a laminated iron core. The upper yoke portion is not shown for simplicity.

As shown in FIG. 1C, in the case of a core reactor with a gap, the magnetic permeability is equivalently reduced by providing a plurality of gaps 13 in the legs of the core, and the number of turns of the coil is appropriately set. The desired reactance is obtained.
In that case, each block-shaped iron core 14 separated by the air gap is referred to as a block iron core.

Referring to FIG. 2, it is a B / H (v / i) characteristic curve of an iron core, and in the case of a normal laminated iron core for a transformer, the magnetic permeability μ in the non-saturated region “a” is very high (approximately several thousand). ), The slope of the B / H characteristic curve is very steep.
However, in the case of a core with a gap, the equivalent permeability μ ′ is a composite value of the permeability μ of the block core and the permeability (substantially 1) of the gap, and an arbitrary value lower than μ can be obtained to some extent. A characteristic curve 'b' that generates a desired rated voltage V0 for a predetermined rated current I0, that is, a reactor having a desired inductance (reactance) value can be provided.

Referring to FIG. 3, it is a diagram showing the distribution of magnetic flux in an elevational view of a conventional voided core reactor as seen in the section XX in FIG. 1 (B).
As shown in FIGS. 1B and 3, the thin iron plate 14 a of the block core 14 is formed by stacking, and the magnetic flux φa is formed substantially vertically along the thin iron plate at the center of the block core and the gap. (The magnetic flux φa penetrates the inside of the thin iron plate 14a up and down in the figure.) However, since the permeability of the air gap is significantly lower than the magnetic permeability of the iron plate at the periphery of the air gap, the magnetic flux φb Enters and exits the iron plate in a swollen form (fringe).

When it is necessary to provide a gap that is somewhat large in order to obtain a desired μ ′, the gap in the iron core with gaps is divided into several to several tens.
The reason for this is that if one of the gaps is too large, the fringing effect becomes excessive.
That is, as described above, the main magnetic flux greatly spreads in the gap portion, the magnetic flux φb entering and exiting the block iron core increases, the component entering and exiting at right angles to the surface of the thin iron plate 14a increases, the eddy current increases, and the coil This is because the magnetic flux φc that attempts to pass through the conducting wire increases, eddy currents that try to counteract this flow, eddy current loss increases, and local temperature rise becomes excessive.
Furthermore, as a result of the main magnetic flux spreading too much, the number of flux linkages with the coil is reduced and the effective reactance is reduced.

  In addition, an attractive force acts between the block cores on both the upper and lower sides of this gap, and a mechanical repulsive force acts between the thin iron plates in the block core, resulting in magnetostrictive sound especially in the vicinity of fringing due to the growth and change of magnetic field lines. Together with it, it causes vibration and noise.

Referring to FIG. 4, it is a plan view of a radial block core 14 in a conventional reactor.
As shown in FIG. 4, in particular, a large reactor generally adopts a structure in which the leg block iron core is changed from a laminated shape to a radial shape (radial shape) in order to partially improve the above problem.
That is, the thin iron plates 14a having different widths are sequentially stacked to form the fan-shaped sub blocks 14z, which are arranged in a circle to form a cylindrical block core.

  In the case of such a radial iron core, the surface of the thin iron plate is not exposed. Therefore, when the fringing magnetic flux enters and exits from the 'Y' direction in the figure, it always enters and exits from the thickness direction of the thin iron plate. Current loss can be suppressed. However, in the radial iron core, the lamination process of thin iron plates is not as easy as a normal iron core, and the problems of vibration and noise inherent to the block iron remain unsolved.

  In addition, for vibration and noise, block iron cores are singly united, in the case of laminated iron cores, holes are drilled and tightened with bolts, and in the case of radial iron cores, they are hardened with compounds. Various measures have been taken, such as placing a gap piece made of resin laminate, ceramic material, etc., and tightening with an upper and lower tightening stud so that the iron core and the gap piece are integrated, and placing the whole in a soundproof tank.・ Noise problem cannot be solved.

  In summary, in the case of the reactor according to the prior art, the vibration and noise are large in performance and the loss due to fringing is large.

  In addition, the structure is more complex than that of ordinary laminated core transformers, and the block cores are stacked individually, especially radially, and tightened or hardened with a compound, and the resulting block cores are stacked and assembled to the final core structure. It was difficult to automate manufacturing, requiring man-hours and production time, and there were problems in terms of delivery time and price.

  In addition, when a reactor according to the prior art is used as a shunt reactor, it must be switched directly on the primary coil side, especially in the case of an ultra-high voltage (for example, 66 KV class), an ultra-high voltage and frequently (at least once a day). An expensive circuit breaker for switching) is required, and excitation rush current may become a problem every time the switching operation is performed.

In relation to these conventional techniques, Patent Document 1 discloses a technique relating to a gap material that supports a gap of a block core made of a radial core of a reactor.
Japanese Patent Laid-Open No. 06-267758

  An object of the present invention is to provide a reactor that does not use a block core in order to solve the above-described problems, and therefore has low vibration and noise in performance, low loss due to fringing, and low local overheating. .

  Another object of the present invention is to provide a reactor capable of increasing the capacity at a low cost, with high reliability because the manufacturing technology of a laminated core transformer having a simple and stable iron core structure can be used.

  Another object of the present invention is to provide a shunt reactor in which an inexpensive circuit breaker for low voltage can be used and there is no problem of excitation rush.

  The reactor according to the present invention made to achieve the above object is a reactor using an iron core according to claim 1, wherein each phase iron core is composed of a main iron core and a bypass iron core, and the main iron core is disposed inside. A secondary coil is wound around a primary coil on the outer side, and a leg portion of the bypass iron core is installed at a position of a main gap located outside the secondary coil inside the primary coil. It is characterized by a short circuit.

  Preferably, as described in claim 5, two bypass iron cores are provided for each phase, a control coil is wound around each of the phases, and the control coils are connected so as to perform DC excitation in opposite directions. To do.

  In addition, as described in claim 6, only the yoke portion of the bypass core is divided into two parts, and a control coil is wound around each of the two parts, and the control coils are connected so that direct current excitation is performed in opposite directions. It is characterized by that.

  Preferably, as described in claim 2, one end of the secondary coil is connected to one end of the primary coil, and the other end is connected to a tap provided in an intermediate portion of the primary coil. The primary coil and the secondary coil are connected so as to be depolarized.

  The reactor according to the present invention made to achieve the above object is a reactor using an iron core as set forth in claim 3, wherein the iron core of each phase includes a main iron core and a bypass iron core, and the main iron core and the bypass iron respectively. A primary coil and a secondary coil are wound so as to surround the leg of the iron core and the leg of the main iron core, and one end of the primary coil and one end of the secondary coil are connected to each other to form a single-winding transformer And connecting one end of the secondary coil or a tap provided in the middle of the secondary coil and the other end of the secondary coil, respectively, so that all or part of the secondary coil is respectively connected Are short-circuited.

  The reactor according to the present invention made to achieve the above object is a reactor using an iron core as set forth in claim 4, wherein the iron core of each phase is composed of a main iron core and a bypass iron core, and the main iron core and the bypass iron respectively. A primary coil, a secondary coil, and a tertiary coil are wound so as to surround the legs of the iron core, the legs of the main iron core, and the legs of the bypass iron core, and one end of the primary coil and the third coil One end is connected, the other end of the tertiary coil and one end of the secondary coil are connected, and one end of the secondary coil or a tap provided in the middle of the secondary coil and the 2 By connecting the other end of the secondary coil, all or a part of the secondary coil is short-circuited.

  According to a seventh aspect of the present invention, the primary coil has a letter “8” shape so that the bypass core portion and the main core portion are divided and wound.

  A reactor according to the present invention made to achieve the above object is a reactor using an iron core as defined in claim 8, wherein a secondary coil is arranged on the inner side so as to surround the main iron core of each phase. A primary coil is wound, and the secondary coil has one end connected to one end of the primary coil and the other end connected to a tap provided in an intermediate portion of the primary coil. The coil and the secondary coil are connected so as to be depolarized.

  Preferably, as described in claim 9, the circuit for short-circuiting the secondary coil is equipped with a circuit breaker or a disconnector.

  According to the present invention, since a block iron core is not used, a reactor with low vibration and noise in performance, low loss due to fringing, and low local overheating can be obtained.

  Further, according to the present invention, since a manufacturing technique of a laminated core transformer with a simple and stable iron core structure can be used without using a block iron core, a reactor capable of increasing the capacity with low cost and high reliability can be obtained.

  Further, according to the present invention, since the circuit breaker can be provided on the secondary side, an inexpensive circuit breaker for low voltage can be used, and a shunt reactor that does not generate exciting rush current can be obtained.

Hereinafter, embodiments of a reactor according to the present invention will be described in detail with reference to the accompanying drawings.
A description of the same parts as those of the prior art or the above-described embodiments may be omitted.

With reference to FIG. 5, the structure of the reactor which concerns on a 1st Example is demonstrated.
5A is an overall configuration diagram, FIG. 5B is a plan view, and FIG. 5C is an elevation view.
In FIG. 5 and the following similar figures, (A), (B), and (C) all show only one phase in the case of a single phase or three phases.
In the following description, the configuration and operation principle will be described using a single-phase circuit for simplicity. However, the same description can be applied to a multi-phase (three-phase) circuit in principle.

In this embodiment, the iron core consists of a frame-shaped lap laminated iron core and forms a closed magnetic circuit type.
The vertical part of the frame shape is called the leg part, and the horizontal part is called the yoke part. The frame-shaped iron cores 10 and 40 are arranged in parallel, and one iron core 10 is a main iron core and the other iron core 40 is a bypass iron core.
The secondary coil 30 is wound around the innermost part around the leg portion 11 of the main iron core 10, and the primary coil 20 is concentrically formed outside the secondary coil 30 and the leg portion 41 of the bypass iron core 40 is also wrapped together. Make the structure so that it winds.
Both ends of the secondary coil are directly short-circuited.

The legs of both iron cores are formed by laminating thin steel plates 11a and 41a, and are lap jointed to lower yoke parts 15 and 45 and an upper yoke part (not shown), respectively.
These structures are the same as those for ordinary transformers.

First, a case where both ends of the secondary coil are temporarily opened in this configuration state will be considered.
When an AC voltage v is applied to both ends of the primary coil 20, a main magnetic flux corresponding to the integral value is induced.
The main magnetic flux consists of the sum of the interlinkage magnetic flux φM between the primary and secondary coils and the magnetic flux not interlinked, and the non-interlinkage magnetic flux increases according to φL by which the main magnetic flux is bypassed by the bypass iron core. The magnetic flux exchange φM, and therefore the secondary induced voltage proportional to φM, decreases as φL increases.

That is, the secondary induced voltage increases or decreases according to the ratio of the cross-sectional area of the main iron core to the sum of the cross-sectional areas of the bypass iron core and the main iron core.
Accordingly, the secondary capacity, that is, the rated capacity (the product of the rated current and the rated voltage) on the secondary coil side also depends on the ratio of the cross-sectional area of the main core to the sum of the cross-sectional areas of the bypass core and the main core. Increase or decrease.
In this case, that is, when the secondary coil is opened, the main magnetic flux may be regarded as passing through the iron core so that the magnetic flux densities of the bypass iron core and the main iron core are the same.

Next, returning to FIG. 5 again, as shown in the figure, when both ends of the secondary coil are short-circuited, a short-circuit current i2 flows, and the interlinkage magnetic flux φM of the main magnetic flux is almost due to the magnetic flux φM ′ generated by the magnetomotive force of the short-circuit current i2. Since the cancellation is canceled, most of the magnetic flux corresponding to the main magnetic flux when the secondary coil is opened moves to the bypass iron core, and the rest passes through the main iron core 10 or the gap between the coils.
This magnetic flux not interlinked with the primary / secondary coil is referred to as a leakage magnetic flux, which is eventually generated by the magnetomotive force of the short-circuit current i2, and therefore its phase is in phase with the short-circuit current i2.

Of the applied voltage of the primary coil when the short-circuit current i2 of the secondary coil becomes the rated current as the transformer, the voltage induced by this leakage magnetic flux is called the leakage reactance voltage, and the short-circuit current i2 and 90 ° It will be out of phase.
Of the applied voltages, a component having the same phase as the short-circuit current i2 is referred to as a resistance voltage, and a vector sum of these components is referred to as an impedance voltage.
The ratio of leakage reactance voltage, resistance voltage, and impedance voltage to the rated voltage of each transformer is called% reactance voltage,% resistance voltage, and% impedance voltage.

In a normal concentric transformer, the% reactance voltage “% IX” is expressed as:
% IX = 4.96f (kVA) rg / e ² h [%]
here,
IX: Leakage reactance voltage [V]
g: width of the gap [m]
f: Frequency [Hz]
e: Induced voltage per turn [V]
kVA: Rated capacity [kVA]
h: coil height [m]
r: average radius of air gap between primary and secondary coils [m]

Therefore,% IX seen from the primary side of the reactor of the present embodiment is a value obtained by adding reactance due to the bypass iron core to the% IX.
In order to actually operate as a reactor, bypass the current so that the primary coil current flowing in accordance with the short-circuit current i2 becomes a desired rated current, and the applied voltage to the primary coil at that time becomes a desired rated voltage. The ratio of the cross-sectional area of the iron core to the main iron core and the impedance between the secondary coil and the primary coil are adjusted. As a result, the total impedance voltage viewed from the primary side becomes 100%.

What is characteristic here is that the secondary coil capacity varies depending on the ratio of the cross-sectional area of the bypass core and the main core.
In the case of a normal transformer, the primary and secondary coil capacities match, and when the secondary coil is short-circuited, the reciprocal of the impedance between the coils is 10 times (10% on an AC effective value basis if the impedance is 10%). An excessive short-circuit current flows, and the transformer is deformed or destroyed.

  However, in the case of the reactor according to the present invention, the interlinkage magnetic flux between the primary and secondary coils is reduced by the bypass iron core, and the secondary capacity is reduced accordingly, so the amount of short-circuit current is about the rated current. Therefore, it is possible to provide a secondary coil having a small copper loss.

Referring to FIG. 6, the B / H (v / i) characteristic curve of the iron core according to the present invention is shown in comparison with the characteristic curve in the case of a normal transformer.
The characteristic curve for a normal transformer is 'a', but the characteristic curve for a secondary coil short-circuited is 'c'.
That is, the applied voltage VR0 commensurate with the rated current I0, that is, the impedance voltage, becomes 10% of the rated voltage V0 when% IZ is 10%.
Here, if the rated voltage V0 is forcibly applied, a current corresponding to the intersection of the 'c' line and V0, that is, 10 times the rated current flows, leading to deformation or destruction.

  However, in the case of the reactor according to the present invention, the leakage impedance voltage is increased by VR * = V0−VR0 by the bypass iron core, so that only the rated current I0 flows even if the rated voltage V0 is applied. The desired characteristic curve 'b' can be obtained using a normal iron core that is not contained.

With reference to FIG. 7, the structure of the reactor which concerns on a 2nd Example is demonstrated.
As shown in FIG. 7, two bypass iron cores 41 and 42 are prepared, and control coils 51 and 52 are wound around the respective leg portions, and the control coils 51 and 52 are connected in series to apply a DC voltage. (The return path of the bypass iron cores 41 and 42 is omitted for simplicity.)

The control coil is connected to the winding direction of the control coil so that the control current ic = Ic (DC value) flowing at this time causes the bypass iron cores 41 and 42 to be DC-excited by equal amounts in opposite directions.
As shown in FIG. 7B, in this embodiment, the leg portions of the bypass iron cores 41 and 42 are provided symmetrically with the leg portion 11 of the main iron core 10 interposed therebetween.

When an AC voltage v is applied in this state, an AC magnetic flux is superimposed on the bypass iron cores 41 and 42, and when the AC magnetic flux is in the same direction as the DC magnetic flux and in the opposite direction, it occurs every half cycle.
Moreover, since the two iron cores are 180 degrees out of phase, when one of the iron cores approaches saturation, the other is away.

When the control current Ic is increased in this state, the iron core on the side where the AC magnetic flux and the DC magnetic flux are in the same direction (assumed to be 41) enters the saturation region near the peak of the AC magnetic flux, and the permeability of the iron core is reduced. A decrease, i.e. an increase in magnetoresistance, begins to occur.
When the control current Ic is further increased, the time during which the iron core 41 is saturated becomes longer and the degree of saturation becomes deeper, and accordingly, the permeability of the iron core decreases, that is, the magnetic resistance of the iron cores 41 and 42 gradually increases. .

  The AC magnetic flux by the AC voltage v is the sum of the magnetic fluxes φM, φL1, and φL2 passing through the main iron core 10 and the bypass iron cores 41 and 42 inside the primary coil 20, and the magnetic flux depends on the magnitude of the magnetic resistance of each iron core. Distributed.

  In the case of a reactor in which the secondary coil is short-circuited, the magnetic flux φM of the main iron core 10 is almost almost canceled by the magnetic flux φM ′ due to the magnetomotive force of the secondary short-circuit current i2, so that the magnetic resistance of the main iron core is equivalently Bypass iron cores 41 and 42 carry most of the AC magnetic flux.

  However, when the control current Ic is not zero but finite, the magnetic resistance of the bypass iron cores 41 and 42 increases in a certain phase range of the applied AC voltage according to the value of Ic. Magnetic flux leaking into the gap between the coils increases.

Eventually, as described above, the sum of leakage reactances by the bypass cores 41 and 42 can be changed within a certain range by the control current Ic.
That is, the reactance value of the reactor can be adjusted only by changing a small DC current Ic. Therefore, when compared with switching by a normal tap or the like, it can be realized easily and continuously with a short time response.

With reference to FIG. 8, the structure of the reactor which concerns on a 3rd Example is demonstrated.
As shown in FIG. 8A, the leg portions of the bypass iron cores 41 and 42 are common, the upper and lower yoke portions are divided into two, and two sets of control coils 51 and 52 are wound around the upper and lower yoke portions, respectively. Yes. (In FIGS. 8B and 8C, only the lower yoke portions 45 and 46 and the lower control coils 51 and 52 are shown for simplicity.)
The winding direction and connection of the control coil are such that the control current ic = Ic (DC value) causes the bypass iron cores 41 and 42 to be DC-excited in equal amounts in opposite directions.

  According to this embodiment, since only the magnetic resistance of the yoke portion is controlled as compared with the second embodiment, the ratio of the adjustment amount to the magnetic resistance of the entire bypass iron core is small, and the adjustment range of the reactance is relatively small. In the case of a reactor, it can be adjusted accurately.

With reference to FIG. 9, the structure of the reactor which concerns on a 4th Example is demonstrated.
In any of the above-described Examples 1 to 3, the secondary coil is installed alone and short-circuited, that is, insulated from the primary coil.

Also in this embodiment, the arrangement of the iron core and the coil may be the same as that of the above-described embodiment. For example, the case of FIG. 9 is the same as FIG. 5 in the case of the first embodiment.
However, in this embodiment, one terminal of the secondary coil is connected to one terminal of the primary coil (this is called a common connection point), and the other terminal of the secondary coil is provided in the middle of the primary coil. Is connected to the tap T in a depolarized manner.
That is, when the other terminal of the secondary coil is temporarily opened from the tap T, the voltage at the tap T is a predetermined value from the voltage induced at the other terminal of the secondary coil when viewed from the common connection point. (Hereinafter referred to as tap difference voltage).

In this case, the value of the secondary short-circuit current is a value limited by the impedance between the primary and secondary coils using the tap difference voltage as a voltage source.
If this is seen from a primary side, a primary coil will become a structure of a single volume transformer.
That is, from the other terminal of the primary coil to the tap is a series coil, and from the tap to the common connection point of the primary coil is a shunt coil, and the secondary coil is connected to the shunt coil as a load. This is equivalent to the flow of i2. Therefore, the primary input current according to the ampere-turn law of the autotransformer flows through the series coil and the shunt coil.

By adjusting the ratio of the cross-sectional area of the bypass core and the main core so that this current becomes the rated current, the impedance between the primary and secondary coils is determined, and the desired reactor function is determined by determining the tap differential voltage. Can provide.
That is, the degree of freedom in design of the position of the intermediate tap increases, and when the tap differential voltage is increased, the current i2 of the secondary coil increases, and between the shunt coil, that is, the tap of the primary coil and the common connection point, 2 Since the current i2 of the secondary coil flows in the direction of canceling the primary current i1, the required capacity of the primary coil is reduced, and the same reactor capacity can be obtained with a smaller coil size than in the first embodiment. .
Conversely, when the tap difference voltage is reduced, the current i2 of the secondary coil can be reduced, and the reactance value viewed from the primary side can be adjusted with high accuracy.
The secondary coil capacity varies depending on the ratio of the bypass iron core to the whole as in the above-described embodiment.

With reference to FIG. 10, the structure of the reactor which concerns on a 5th Example is demonstrated.
In the present embodiment, the primary coil 20 and the secondary coil 30 are wound so as to surround the legs of the main iron core 10 and the bypass iron core 40 and the legs of the main iron core 10, respectively. One end of the secondary coil 30 is connected, that is, the primary coil and the secondary coil are configured as a series coil and a shunt coil, respectively.
In the autotransformer, all the secondary coils are short-circuited by connecting one end of the secondary coil 30 and the other end of the secondary coil 30.

  Eventually, in Example 4 described above, the secondary coil as a load is omitted and the tap T is directly connected to the common connection point, and the required capacity of the shunt coil, that is, the secondary coil may be minimized, and the primary coil. Can satisfy the required capacity of the series coil, and may be smaller than the primary coil of the fourth embodiment by the amount of the secondary coil. In addition, the same reactor capacity can be obtained with a coil size smaller than that of the fourth embodiment. Can be obtained.

With reference to FIG. 11, the structure of the reactor which concerns on a 6th Example is demonstrated.
In this embodiment, the third coil 35 is further wound around the bypass iron core 40 in the fifth embodiment, and the primary coil 20 and the third coil 35 are connected in series to form a series coil as a single winding transformer.

  According to the present embodiment, the degree of design freedom of the number of turns of the tertiary coil is increased as compared with the fifth embodiment, and when compared with the first and fourth embodiments, the total coil size is generally the same, as viewed from the primary side. Reactance capacity can be increased.

With reference to FIG. 12, the structure of the reactor which concerns on a 7th Example is demonstrated.
In this embodiment, compared with the first embodiment (FIG. 5), the primary coil 20 has a leg portion 11 of the main iron core 10 including the secondary coil 30 and the bypass iron core in an “8” shape. It is rolled up.
In the central portion of the “8” shape in FIG. 12B, the upper winding and lower winding of the primary coil 20 are alternately stacked.

Since there are few gaps between both the iron cores, the secondary coil, and the primary coil, the leakage magnetic flux to the outside of the iron core is minimized, design errors are reduced, and design accuracy can be improved.
Although the arrangement of the iron core and the coil in the present embodiment corresponds to that in the first embodiment, it can be applied to the configurations of the third embodiment (FIG. 8) and the fourth embodiment (FIG. 9), for example.
Further, when the leg portion of the bypass core is divided into two as in the configuration of the second embodiment (FIG. 7), the primary coil of the bypass core 42, the main core 11, and the bypass core 41 is “8”. It is preferable to wrap them individually so as to continue the shape.

With reference to FIG. 13, the structure of the reactor which concerns on an 8th Example is demonstrated.
This embodiment lacks a bypass iron core when compared with the fourth embodiment (FIG. 9).

  Even if the bypass core is missing, if the tap T position and the coil winding ratio are properly selected, a reactor with almost the rated capacity can be realized, especially in the case of a small-capacity reactor. it can.

With reference to FIG. 14, the structure of the reactor which concerns on a 9th Example is demonstrated.
This embodiment is different from the first embodiment in that the switch Sw is interposed in the secondary side short circuit.
The switches Sw can be interposed in the secondary side short circuit also for the other configurations of the second to eighth embodiments.

In particular, in the case of a shunt reactor installed in a high-voltage system, a switch Sw is inserted on the secondary side as a circuit breaker or disconnector so that it can be opened and closed, and the primary side is directly connected to the system.
In this way, the characteristics of the reactor according to the present invention that the above-mentioned "secondary side operates at a lower voltage than the primary side and the secondary short-circuit capacity is small" can be utilized, for example, to the system of the shunt reactor At the time of insertion / breaking, there is an effect that an inexpensive, low-voltage multi-frequency circuit breaker or low-voltage switch can be used as the switch Sw instead of an expensive high-voltage / large-current multi-frequency circuit breaker.
In addition, since the presence / absence of reactance connection to the system can be controlled by opening / closing the secondary side switch Sw, it is possible to eliminate the occurrence of exciting rush current.

In recent years, the power system has been increasing in capacity and ultra-high voltage, and in addition, the number of distributed power sources such as wind power generation and solar power generation has increased. There is concern about the deterioration of quality.
As one of the measures to stabilize the power quality, a high-quality reactor that can withstand high voltage and can perform continuous reactance value control at high speed is indispensable. However, it has been difficult to supply at a low cost while securing the above-described characteristics with conventional block core reactors, saturable reactors, and switching reactors using mechanical taps.
The power reactor according to the present invention meets this requirement for the first time in practical use.

It is a figure explaining the structure of the reactor by a prior art, (A) is a whole block diagram, (B) is a top view, (C) is an elevation view. It is a figure which shows the B / H (v / i) characteristic curve of the iron core with a space | gap by a prior art. It is a figure which shows the cross section and magnetic flux distribution of a block iron core in the void core reactor by a prior art. It is a top view of the radial block iron core 14 in the reactor by a prior art. It is a figure explaining the structure of the reactor which concerns on 1st Example by this invention, (A) is a whole block diagram, (B) is a top view, (C) is an elevation view. It is a figure which shows the B / H (v / i) characteristic curve of the iron core of the reactor by this invention. It is a figure explaining the structure of the reactor which concerns on 2nd Example by this invention, (A) is a whole block diagram, (B) is a top view, (C) is an elevation. It is a figure explaining the structure of the reactor which concerns on 3rd Example by this invention, (A) is a whole block diagram, (B) is a top view, (C) is an elevation. It is a figure explaining the structure of the reactor which concerns on the 4th Example by this invention, (A) is a whole block diagram, (B) is a top view, (C) is an elevation view. It is a figure explaining the structure of the reactor which concerns on the 5th Example by this invention, (A) is a whole block diagram, (B) is a top view, (C) is an elevation. It is a figure explaining the structure of the reactor which concerns on the 6th Example by this invention, (A) is a whole block diagram, (B) is a top view, (C) is an elevation view. It is a figure explaining the structure of the reactor which concerns on the 7th Example by this invention, (A) is a whole block diagram, (B) is a top view, (C) is an elevation. It is a figure explaining the structure of the reactor which concerns on the 8th Example by this invention, (A) is a whole block diagram, (B) is a top view, (C) is an elevation. It is a figure explaining the structure of the reactor which concerns on the 9th Example by this invention, (A) is a whole block diagram, (B) is a top view, (C) is an elevation view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Iron core, main iron core 11 Leg part 11a, 14a, 15a, 41a, 42a Thin iron plate 13 Space | gap 14 Block core 14z Radial core fan-shaped subblock 15, 45 Lower yoke part 20 Coil, Primary coil 30 Secondary coil 35 Tertiary Coil 40, 41, 42 Bypass iron core 51, 52 Control coil T Tap Sw switch

Claims (9)

  In a reactor using an iron core, the iron core of each phase is composed of a main iron core and a bypass iron core. The main iron core is wound with a secondary coil on the inner side and a primary coil on the outer side, A reactor in which a leg portion of the bypass iron core is installed at a position of a main gap located outside a secondary coil, and the secondary coil is short-circuited.   The secondary coil has one end connected to one end of the primary coil, the other end connected to a tap provided in an intermediate portion of the primary coil, and the primary coil and the secondary coil are connected to each other. The reactor according to claim 1, wherein the reactor is connected so as to be depolarized.   In a reactor using an iron core, the iron core of each phase consists of a main iron core and a bypass iron core, and a primary coil and a secondary coil are respectively enclosed so as to surround the main iron core, the bypass iron leg, and the main iron leg. Winding, connecting one end of the primary coil and one end of the secondary coil to form a single-winding transformer, and a tap provided at one end of the secondary coil or in the middle of the secondary coil And the other end of the secondary coil are connected to each other to short-circuit all or part of the secondary coil.   In a reactor using an iron core, the iron core of each phase is composed of a main iron core and a bypass iron core. A secondary coil, a secondary coil and a tertiary coil are wound, one end of the primary coil and one end of the tertiary coil are connected, and the other end of the tertiary coil and one of the secondary coils are connected. By connecting the ends and connecting one end of the secondary coil or a tap provided in the middle of the secondary coil and the other end of the secondary coil, respectively, The reactor characterized by having short-circuited the part.   5. The bypass iron core is provided with two each phase, and a control coil is wound around each of the bypass iron cores, and the control coils are connected so that direct current excitation in opposite directions is performed. Reactor.   2. The bypass iron core is divided into two parts, and a control coil is wound around each of the two parts, and the control coils are connected so as to perform DC excitation in opposite directions. The reactor according to 3 or 4.   5. The reactor according to claim 1, wherein the primary coil has a shape of “8” so that the bypass core portion and the main core portion are divided and wound.   In a reactor using an iron core, a secondary coil is wound on the inner side and a primary coil is wound on the outer side so as to surround the main core of each phase, and one end of the secondary coil is one of the primary coils. A reactor, wherein the reactor is connected to one end, the other end is connected to a tap provided in an intermediate portion of the primary coil, and the primary coil and the secondary coil are connected so as to be depolarized. The reactor according to claim 1, 3, 4, or 8, wherein a circuit for short-circuiting the secondary coil is equipped with a circuit breaker or a disconnector.

Images