JPH085534Y2 - Variable reactor for electric power - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable power reactor used for controlling a reactor in a static var compensator or the like.

[0002]

2. Description of the Related Art As is well known, conventional reactors include
There are various types such as iron core type, air core type, and iron core type with gap. The inductance of each type depends on the number of windings and dimensions of the reactor and the magnetic circuit material, shape and dimensions. The value is fixed.

Therefore, for example, in the reactor control in the static var compensator, as shown in FIG. 4, the effective value of the current flowing into the reactor L is controlled by the ON / OFF control of the semiconductor switching element such as the thyristor S. By adjusting, the lagging reactive power of the reactor L is controlled. In this static var compensator, the controlled lagging reactive power is combined with the lagging reactive power by the power capacitor SC so that the lagging reactive power to the lagging reactive power required by the system can be obtained. It is configured to supply continuously.

However, in this case, since the firing angle of the reactor L is controlled, the filter F for suppressing the harmonics is required, which complicates the equipment structure and increases the construction cost. In FIG. 4, Vs is the system voltage, Qs
Is reactive power and T is a transformer.

Further, for example, in JP-A-52-41865 and JP-A-62-274708, an iron core having a part of the magnetic path opened and an iron core having a closed magnetic path at the opened magnetic path part are disclosed. A variable reactor is shown in which one piece is inserted, the main winding and the control winding are respectively wound on both iron cores, and the magnetic flux of the control winding is orthogonalized to the magnetic path of the reactor on which the main winding is wound. Has been shown to be used in a reactive power compensator (Fig. 6 of JP-A-62-274708).
However, the core structure of these is extremely complicated.

[0006]

As described above, in the static var compensator using the conventional semiconductor switching element, the equipment structure is complicated and the equipment cost is increased. Only applied.
Also, there is no example of using the variable reactor as described above in the actual system.

Therefore, the present invention has been made in view of the above circumstances, and provides a variable power reactor that is extremely simple in structure and easy to manufacture and is suitable for use in a static var compensator or the like. With the goal.

[0008]

A variable power reactor according to the present invention comprises a first C-shaped cut core around which a main winding is wound and a second C-shaped cut around which a control winding is wound. The core and the cut surfaces thereof face each other, and the other cut core is rotated by 90 ° in the twisting direction with respect to one cut core. It is configured such that a minute interval is formed with an inclusion made of a conductive material interposed therebetween.

[0009]

According to the above-mentioned structure, by applying a voltage to the main winding, the first C-shaped cut core and the inclusion and the second C-shaped cut core form a first magnetic circuit with a gap. The second C-shaped cut core and the inclusions and the first C-shaped cut core constitute a second magnetic circuit with a gap by applying a voltage to the control winding. Then, the magnetic flux of the second magnetic circuit with the gap has the first and second C
In the facing surface of the shaped core, the magnetic flux in the first gap magnetic circuit is in the same direction or in the opposite direction, and the magnetic permeability of the facing surface changes and affects the first gap magnetic circuit.

That is, when the magnetic flux of the second magnetic circuit with a gap is controlled by controlling the voltage applied to the control winding, this magnetic flux control acts on the magnetic resistance of the first magnetic circuit with a gap, and the main winding The inductance of the wire is changed. Therefore, the inductance of the main winding can be changed by changing the value of the voltage applied to the control winding. Therefore, it can be realized with an extremely simple structure, is easy to manufacture, and is very suitable for use in a static var compensator or the like.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. In FIG. 1, 11 is the first C
The main winding 12 is wound around the cut core. Also,
In the figure, 13 is a second C-shaped cut core, around which the control winding 14 is wound. Then, the first and second C-shaped cut cores 11 and 13 are second to the first C-shaped cut core 11 with their cut surfaces facing each other.
Rotate the C-shaped cut core 13 of 90 ° in the twisting direction,
In this state, the cut cores 11 and 13 are set so as to form a minute gap between the cut cores 11 and 13 with an inclusion 15 made of a non-magnetic material and a non-conductive material interposed therebetween, and are formed into a core shape with a gap. . Note that FIG. 2 shows an equivalent circuit in the structure shown in FIG.

If an AC voltage e1 is applied to the main winding 12 and a current i1 flows in the direction of the arrow shown in the figure, both ends of the first C-shaped cut core 11, the inclusions 15 and the second C are cut.
A closed magnetic circuit with a gap is formed by both ends of the shape cut core 13, and a magnetic flux φ is generated as shown by a dotted arrow in FIG.
1 occurs. In this case, a part of the magnetic flux φ 1 is applied to the second C-shaped cut core 13 on which the control winding 14 is wound, but the second C-shaped cut core 13 is Since it is rotated 90 degrees in the twisting direction,
No induced voltage is generated in the control winding 14.

Similarly, an AC voltage e is applied to the control winding 14.
2 is applied and a current i2 flows in the direction of the arrow shown in the figure, the closed magnetic circuit with a gap is formed by the both ends of the second C-shaped cut core 13, the inclusions 15 and the both ends of the first C-shaped cut core 11. And a magnetic flux φ2 is generated as shown by the dotted arrow in FIG. Also in this case, a part of the magnetic flux φ 2 is generated by the first C-shaped cut core 1 around which the main winding 12 is wound.
However, since the first C-shaped cut core 11 is rotated by 90 ° in the twisting direction with respect to the second C-shaped cut core 13, no induced voltage is generated in the main winding 12.

That is, when the AC voltage e1 is applied to the main winding 12, a closed magnetic circuit with a gap is formed and a magnetic flux φ1 is generated. When the AC voltage e2 is applied to the control winding 14, a closed magnetic circuit with a gap is formed and a magnetic flux φ2 is generated.

When AC voltages e1 and e2 are applied to the main winding 12 and the control winding 14, respectively, and the resulting instantaneous values of the magnetic fluxes φ1 and φ2 are taken in the directions shown by the arrows in FIG. On the facing surfaces a and d of the first and second C-shaped cut cores 11 and 13, both magnetic fluxes φ1 and φ2 are in the same direction, and on the facing surfaces b and c, both magnetic fluxes φ1 and φ2 are in opposite directions, This does not change at any instantaneous value of both magnetic fluxes φ1 and φ2.

Next, an AC voltage e1 is applied to the main winding 12, the resulting instantaneous value of the magnetic flux φ1 is set in the direction shown by the arrow in FIG. 1, and a DC voltage e2 is applied to the control winding 14. Assuming that the direction of the resulting magnetic flux φ 2 is constant in the direction shown by the arrow in FIG. 1, both magnetic fluxes φ 1,
φ2 is in the same direction, and both magnetic fluxes φ1 and φ
2 are opposite to each other. Further, when the direction of the instantaneous value of the magnetic flux φ1 is reversed, the direction of the magnetic flux φ2 does not change. Therefore, the two magnetic fluxes φ1 and φ2 are opposite to each other on the facing surfaces a and d, and the two magnetic flux φ1 are opposite to each other on the facing surfaces b and c. , Φ2 are in the same direction. Then, this relationship is periodically repeated depending on the direction of the instantaneous value of the magnetic flux φ1.

That is, irrespective of whether the voltage applied to the control winding 14 is AC or DC, the facing surfaces a, b,
In c and d, opposing surfaces in which the directions of both magnetic fluxes φ1 and φ2 are opposite to the same direction are formed. Therefore, both magnetic flux φ1
The inductance of the main winding 12 can be controlled by changing the magnetic permeability of the opposing surfaces in which the directions of φ 2, φ 2 are opposite to the same direction by the voltage applied to the control winding 14. Therefore, as shown in FIG. 3, by changing the voltage applied to the control winding 14, the inductance of the main winding 12 can be changed. In addition,
The present invention is not limited to the above-described embodiment, and can be variously modified and implemented without departing from the scope of the invention.

[0018]

As described in detail above, according to the present invention,
The extremely simple iron core structure can provide a variable power reactor suitable for use in a static var compensator or the like.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a variable power reactor according to the present invention.

FIG. 2 is a circuit configuration diagram showing an equivalent circuit of the embodiment.

FIG. 3 is a characteristic diagram showing a relationship between a control winding applied voltage and a main winding inductance in the example.

FIG. 4 is a block diagram showing a conventional static var compensator using a semiconductor switching element.

[Explanation of symbols]

11 ... 1st C type cut core, 12 ... Main winding, 13 ... 2nd C type cut core, 14 ... Control winding, 15 ... Inclusion.

Claims (1)

[Scope of utility model registration request] 1. A state in which a first C-shaped cut core on which a main winding is wound and a second C-shaped cut core on which a control winding is wound have their cut surfaces opposed to each other. Then, the other cut core is rotated 90 ° in the twisting direction with respect to the one cut core, and in this state, a small gap is sandwiched between the cut cores by interposing an inclusion made of a non-magnetic material and a non-conductive material. A variable reactor for electric power, wherein the variable reactor for electric power is configured to be formed, and the value of the voltage applied to the control winding is changed to change the inductance of the main winding.