JP2013125798A - Reactor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reactor device capable of reducing the manufacturing cost by achieving reduction in material cost by miniaturization when applied to a starter of an induction motor.SOLUTION: A reactor device for starting an induction motor includes: a standing core-type core 1 having three leg parts 11-13; and three windings 2-4 wound around the leg parts 11-13 of the core 1. The core 1 is formed so as not to provide a gap. Furthermore, intensity of a magnetic field in the core 1 is made in a range of 500 [AT/cm] or more and 1200 [AT/cm] or less, and the size of the core 1 is fixed so as to be in the range thereof.

Description

  The present invention relates to a reactor device for starting an induction motor.

Conventionally, this type of reactor device includes an iron core composed of laminated steel sheets and a winding wound around a part of the iron core, and there is no gap in the middle of the magnetic path. (See Patent Document 1 and the like).
Moreover, in the reactor apparatus applied to the start of a three-phase induction motor, it is provided with an iron core composed of laminated steel plates and having three legs, and a winding wound around each of the three legs. It is known that there is no gap in the middle.

Japanese Patent Publication No.46-25045

By the way, the conventional reactor apparatus is comprised as mentioned above, and is comprised from the iron core which consists of laminated steel plates etc., and the coil | winding which consists of copper, and these occupy most of material costs.
For this reason, in the conventional reactor apparatus applied to the starter of the induction motor used as a power source in a factory or the like, the material cost increases as the size of the induction motor increases, and there is a problem that the manufacturing cost increases.

Under such a background, when applied to a starter of an induction motor, it is possible to reduce the material cost by reducing the size, thereby reducing the manufacturing cost. The appearance of a reactor device was desired.
Accordingly, an object of the present invention is to reduce the material cost by reducing the size while maintaining the starting performance and quality required when applied to the starter of the induction motor, thereby reducing the production cost. It is providing the reactor apparatus which can aim at reduction.

In order to solve the above problems and achieve the object of the present invention, the present invention has the following configuration.
That is, the first invention includes a reactor device for starting an induction motor, including three leg portions and two connecting portions integrally connected to both end sides of the three leg portions, and laminating steel plates. An inner iron-type core configured as described above, and three windings wound around each of the three legs, the core configured not to provide a gap, and a magnetic field in the core The strength of the core is in the range of 500 [AT / cm] or more and 1200 [AT / cm] or less, and the size of the core is determined so as to be within the range.

  According to a second invention, in the first invention, the core has a rectangular outer shape when viewed from the front, a plane, and a side, the outer height is H, and the outer length is L. Further, the core forms a magnetic path having a width W and a thickness T, and the height H of the outer shape is not less than 1.25 times the length L of the outer shape and is 2.5. The thickness T of the magnetic path is not less than 0.6 times and not more than 1.4 times the width W of the magnetic path.

According to a third invention, in the second invention, the core penetrates in the thickness direction at the left and right positions of the front center, and the vertical length of the opening is 2 and the horizontal length is 2 Each of the two windows has a vertical length a of 1.1 times or more and 3.4 times or less of the horizontal length b. To do.
According to a fourth aspect of the present invention, in the first to third aspects of the present invention, the two steel frames sandwiching the stacked steel plates from the thickness direction and the upper ends of the two rectangular frames are connected to each other to connect the steel plates. Two first connection screws for tightening the steel plate from the thickness direction, and two second connection screws for connecting the lower ends of the two rectangular frames to tighten the steel plate from the thickness direction. It is characterized by providing.

According to a fifth invention, in the first to fourth inventions, the core has substantially the same cross-sectional area as each of the three leg portions and the two connection portions.
In a sixth aspect based on the first, fourth or fifth aspect, each of the three windings comprises a main winding and a secondary winding, and each of the main winding and the secondary winding Is wound around the leg portion.

In the present invention, the core is configured such that no gap is provided, and the magnetic field strength in the core is in the range of 500 [AT / cm] or more and 1200 [AT / cm] or less, and is within that range. The size of the core was determined.
With this configuration, when determining the size of the core, it is possible to significantly reduce the material while maintaining the necessary performance and quality, and it is possible to reduce the size of the core. However, there is concern overheating due to iron loss.

  On the other hand, when the present invention is used for an induction motor starter, since its own winding is connected to the induction motor winding, the current is reduced compared to the case where the own winding is used alone. Distortion is improved. Also, a large current at the time of start flows through its own winding for a short period of time until the end of the start. There is no.

Therefore, when the present invention is applied to an induction motor starter, it can be put into practical use while maintaining necessary performance and quality even if the core size is reduced.
Therefore, according to the present invention, when applied to a starter of an induction motor, it is possible to reduce the material cost by reducing the size while maintaining the necessary performance and quality, thereby reducing the manufacturing cost. Can be achieved.

It is a top view which shows the structure of embodiment of this invention. It is a front view of this embodiment. It is a right view of this embodiment. It is a disassembled perspective view of the principal part of this embodiment. It is a perspective view explaining the magnitude | size of an iron core. It is a figure which shows the example of a connection in the case of applying this embodiment to the starter of a three-phase induction motor. It is a perspective view which shows the structure of the 1st modification of embodiment of this invention. It is a figure which shows the example of a connection in the case of applying this 1st modification to the starter of a three-phase induction motor. It is a figure which shows the structure of the 2nd modification of embodiment of this invention, (A) is a perspective view which shows the structure of a core, (B) is a perspective view which shows the structure of the state which wound the core around the core It is. It is a figure which shows the example of a connection in the case of applying this 2nd modification to the starter of a three-phase induction motor. It is a perspective view which shows the structure of the 3rd modification of embodiment of this invention. It is a figure which shows the example of a connection in the case of applying this 3rd modification to the starter of a three-phase induction motor. It is a figure for demonstrating the 4th modification-6th modification of embodiment of this invention.

Embodiments of the present invention will be described below with reference to the drawings.
(Background of the completion of the invention)
The present invention is capable of reducing the material cost by reducing the size while maintaining the necessary performance and quality, and the demand for the appearance of a new reactor device that can reduce the manufacturing cost. Under the symposium, we have conducted earnest research.

And since this invention acquired the new knowledge in the process which advances earnest research, and was completed based on this new knowledge, that point is demonstrated below before description of embodiment.
When designing a reactor device that functions as a reactance with respect to alternating current as in the present invention, it is usual to provide a gap in the core to avoid magnetic saturation. Moreover, the design theory of a reactor gap is common.

In other words, if the core is not provided with a gap, when used alone, the distortion rate of the current flowing through the circuit is large, and it is unsuitable for long-term use due to iron loss. Moreover, the design theory of a reactor without a gap is not common.
However, when the reactor device is applied to an induction motor starter, since its own winding is connected to the induction motor winding, the current flowing through the circuit is reduced and distortion is reduced compared to the case where it is used alone. We have found that the rate is improved.

In addition, when used as a starter for an induction motor, a large current at the time of starting flows in its own winding for a short time until the end of the starting, and a large current is passed through the winding for a long time. Therefore, the knowledge that there is no concern of overheating due to core iron loss and copper loss was obtained.
Therefore, the present invention, as a result of extensive research by the inventors based on these findings, has resulted in a magnetic field strength in the core of 500 [AT / cm] or more and 1200 [AT / cm] or less. It can be put to practical use if set to, that is, it has been found that a significant material reduction effect can be obtained while maintaining the required performance and quality, and the core size is determined so as to be within that range. .

(Configuration of the embodiment)
Next, the structure of embodiment which concerns on the reactor apparatus of this invention is demonstrated with reference to FIGS.
1 is a plan view of this embodiment, FIG. 2 is a front view thereof, and FIG. 3 is a right side view thereof. FIG. 4 is an exploded perspective view of the main part of this embodiment.
The reactor device according to this embodiment is applied to a starter of a three-phase induction motor, and is wound around the inner iron core 1 and the core 1 as shown in FIGS. Three windings 2 to 4 and a pair of frames 5 and 6 for sandwiching and fixing a steel plate constituting the core 1 from the thickness direction are provided.

  The core 1 is formed by laminating steel plates such as silicon steel plates. As shown in FIG. 4, the core 1 includes three leg portions 11 to 13 and two coupling portions 14 and 15 that are integrally connected to both ends of the leg portions 11 to 13. It is configured so that there are no gaps at any point. Further, windings 2 to 4 are wound around the leg portions 11 to 13 of the core 1, respectively.

  Each of the frames 5 and 6 is formed of a rectangular frame as shown in FIG. 4, and the whole is made of iron or stainless steel. Specifically, the frame 5 includes upper and lower members 51 and 52 and left and right members 53 and 54, which are connected by four sets of bolts 55 and nuts 56 to form a rectangular frame. The frame 6 includes upper and lower members 61 and 62 and left and right members 63 and 64, which are connected by four sets of bolts 65 and nuts 66 to form a square frame.

The frame 5 and the frame 6 sandwich the steel plate constituting the core 1 from the thickness direction, and in this sandwiched state, four coupling screws (connectors) including bolts 71a to 74a and nuts 71b to 74b are used. By doing so, the steel plate is tightened in the thickness direction.
Specifically, through holes 51 a, 51 b, 52 a, 52 b are formed at both ends of the members 51, 52 forming the frame 5. Further, through holes 61 a, 61 b, 62 a, 62 b are formed at both ends of the members 61, 62 forming the frame 6. Then, the members 51 and 52 and the members 61 and 62 are brought into close contact with the front and back surfaces of the connecting portions 14 and 15 of the core 1. In this state, the bolt 71a is passed through the through holes 51a and 61a, the bolt 72a is passed through the through holes 51b and 61b, the bolt 73a is passed through the through holes 52a and 62a, and the bolt 74a is passed through the through holes 52b and 62b. By doing so, the core 1 is supported by the frames 5 and 6.

  As shown in FIGS. 1 to 3, an insulating member 8 is attached to the upper member 51 that forms the frame 5. The connection between the insulating member 8 and the member 51 of the frame 5 is performed using a bolt 82 and a nut 83 via a spacer 81. The insulating member 8 is provided with connection terminals 81 to 83. Although not shown, one end of each of the windings 2 to 4 is connected to the connection terminals R, S, and T.

As shown in FIGS. 1 and 3, an insulating member 9 is attached to the upper member 61 that forms the frame 6. The connection between the insulating member 9 and the member 61 of the frame 6 is performed using a bolt 92 and a nut 93 via a spacer 91. The insulating member 9 is provided with connection terminals U1, U2, V1, V2, W1, and W2. Although not shown, the other ends of the windings 2 to 4 are connected to the connection terminals U1, V1, and W1. Further, although not shown, the intermediate taps of the windings 2 to 4 are connected to the connection terminals U2, V2 and W2, and if necessary, the intermediate taps of Ut, Vt and Wt (t = 3 to 5). Is connected.
The insulating member is a means for fixing the connection terminal and is not directly related to the electrical performance of the reactor. Therefore, the shape and configuration of the insulating member are just an example.

(Core configuration)
As described above, the present invention has been found to be practical if the strength of the magnetic field in the core is in the range of 500 [AT / cm] or more and 1200 [AT / cm] or less. In this way, the size of the core is determined.
Therefore, in this embodiment, for example, the magnetic field strength is set to 700 [AT / cm], and in order to satisfy the magnetic field strength, the size (size) of the core 1 is set to, for example, FIG. As shown in
As shown in FIG. 5, the core 1 is rectangular in shape when viewed from the front, the plane, and the right side, and penetrates in the thickness direction at the left and right positions of the center of the front, and the opening is rectangular. Two windows 16 and 17 are provided.

  As shown in FIG. 5, the core 1 has an outer height H of 140 [mm] and a length L of 225 [mm]. The core 1 has magnetic paths having the same width W and the same thickness T. The core 1 has a width W of 35 [mm] and a thickness T of 22 [mm]. For this reason, the cross-sectional area of the magnetic path is formed the same. Furthermore, as for the size of each opening of the two windows 16 and 17, the vertical length a is 70 [mm], and the horizontal length b is 60 [mm].

For this reason, the ratio between the height H and the length L of the outer shape of the core 1 is as follows.
L / H = 225 / 140≈1.8 (1)
The ratio between the width W and the thickness T of the magnetic path is as follows.
T / W = 22 / 35≈0.65 (2)
Furthermore, the ratio of the vertical length a to the horizontal length b of the window is as follows.
a / b = 70 / 60≈1.17 (3)
Here, since the size (volume) of the core 1 of this embodiment is proportional to the rated output power of the induction motor, it increases in proportion to the rated output power of the induction motor to which this embodiment is applied. The ratio of each size of 1 is the same as the formulas (1) to (3).

On the other hand, equation (1) is for the case where the magnetic field strength is 700 [AT / cm]. In this embodiment, the magnetic field strength is 500 [AT / cm] or more and 1200 [AT] as described above. / Cm] or less in the range.
Therefore, considering this point, in this embodiment, if the expressions (1) to (3) satisfy the relationships of the following expressions (4) to (6), a practically sufficient effect can be obtained.
L / H = 1.25 to 2.5 (4)
T / W = 0.6 to 1.4 (5)
a / b = 1.1-3.4 (6)

  In other words, in this embodiment, the height H of the outer shape of the core 1 is not less than 1.25 times and not more than 2.5 times the length L. Further, the thickness T of the magnetic path of the core 1 is set to be not less than 0.6 times the width W and not more than 1.4 times. Further, the two windows 16 and 17 have a vertical length a that is 1.1 times or more and 3.4 times or less of the horizontal length b.

Here, the dimensional ratio corresponding to the equations (4) to (6) of the core size of the reactor device used as the starter of the induction motor equivalent to this embodiment and having no gap in the conventional iron core is ( 7) to (9).
L / H = 0.6 to 1.2 (7)
T / W = 1.5 to 2.5 (8)
a / b = 3.5 to 7.0 (9)
Comparing the equations (4) to (6) with the equations (7) to (9), the core of this embodiment can be reduced in height as compared with the conventional example, and the cross-sectional area of the core is significantly reduced. You can see that you can.

For this reason, when compared with the size of the core of the conventional reactor device, the size of the core of this embodiment can be reduced by reducing the size of the core as a whole, thereby maintaining the required performance and quality while reducing the price. Can be realized.
Moreover, the core 1 is comprised so that the area of each cross section of the three leg parts 11-13 and the two connection parts 14 and 15 may become equal, as shown in FIG. If comprised in this way, the shape of the steel plate which comprises the core 1 can be limited to several patterns. Therefore, since these may be laminated, this processing and assembly are facilitated.

(Usage example of embodiment)
Next, a usage example of the embodiment having such a configuration will be described with reference to FIG.
FIG. 6 is a connection example when the reactor device of this embodiment is used as the starter 200 of the three-phase induction motor 100, and the windings 2 to 4 are connected as illustrated.
In the circuit of FIG. 6, when starting the three-phase induction motor 100, the contactors SW1 to SW3 are closed while the contactors (switches) SW4 to SW6 of the starter 200 are open. Thereafter, when the start of the three-phase induction motor 100 is completed, the contactors SW4 to SW6 of the starter 200 are closed while the contactors SW1 to SW3 are closed.
For this reason, the windings 2 to 4 according to this embodiment are connected in series to the windings of the three-phase induction motor 100 when the three-phase induction motor 100 is started, and a current flows. Since both ends are short-circuited by SW6, no current flows here.

(Effect of embodiment)
As described above, this embodiment is configured so that the strength of the magnetic field in the core 1 is in the range of 500 [AT / cm] to 1200 [AT / cm].
For this reason, when this embodiment is used alone, there is a concern about deterioration of the current distortion rate and overheating due to iron loss as the size of the core 1 is reduced.
On the other hand, since this embodiment is used as a starter of a three-phase induction motor, its own winding is connected to the winding of the three-phase induction motor, and the current is reduced compared to the case where the own winding is used alone. And distortion is improved. Also, a large current at the time of start flows through its own winding for a short time until the end of the start, and a large current at the time of start does not flow through its own winding for a long time. There is no concern about overheating.

For this reason, when this embodiment is applied to a starter of a three-phase induction motor, it can be put into practical use even if the core 1 is made smaller and the size is reduced.
Therefore, according to this embodiment, when applied to a starter of a three-phase induction motor, it is possible to reduce the material cost by reducing the size, thereby reducing the manufacturing cost. .

(Modification of the embodiment)
(1) First Modification This first modification is based on the configuration of the above embodiment, and the configuration of the windings 2 to 4 wound around the core 1 of FIG. 4 is changed to the winding 2a shown in FIG. It is changed to the configuration of ~ 4a.
That is, the winding 2a includes a main winding 2a-1 and a secondary winding 2a-2, and these two windings are wound around the leg 11 of the core 1. The winding 3a includes a main winding 3a-1 and a secondary winding 3a-2, and these two windings are wound around the leg 12 of the core 1. Further, the winding 4a includes a main winding 4a-1 and a secondary winding 4a-2, and these two windings are wound around the leg portion 13 of the core 1.
FIG. 8 is a connection example when the reactor device of the first modification is used as the starter 200 of the three-phase induction motor 100, and the main windings 2a-1, 3a-1 of the windings 2a-4a, 4a-1 and secondary windings 2a-2, 3a-2, 4a-2 are connected as shown in the figure.

In the circuit of FIG. 8, when starting the three-phase induction motor 100, the contactors SW1 to SW3 are closed while the contactors SW4 to SW6 of the starter 200 are open. For this reason, at the time of start-up, the main windings 2a-1, 3a-1, 4a-1 are connected to the windings of the three-phase induction motor 100 and current flows.
Thereafter, when the start of the three-phase induction motor 100 is completed, the contactors SW4 to SW6 of the starter 200 are closed while the contactors SW1 to SW3 are closed. At this time, a current flows through the secondary winding 2a-2, and the magnetic fluxes of the main winding 2a-1 and the secondary winding 2a-2 cancel each other, thereby eliminating the reactance. Such an operation is similarly performed between the main winding 3a-1 and the secondary winding 3a-2 and between the main winding 4a-1 and the secondary winding 4a-2.

For this reason, the main windings 2a-1, 3a-1, 4a-1 of the windings 2a-4a function as reactance when the three-phase induction motor 100 is started, but lose function as reactance after the start. That is, the primary side is equivalently short-circuited. As a result, the effect of eliminating the need for an external short-circuit contactor can be obtained. In the case of high pressure, since the contactor is large, the space merit becomes large.
In addition, although current flows through the main windings 2a-1, 3a-1, 4a-1 after the start is completed, there is no concern about heat generation due to iron loss because there is no magnetic flux in the iron core.
As described above, contactlessness is achieved for the separation of the reactor on the primary side, and a starting system that does not generate a contactor surge that impairs the life of the device is obtained.

(2) Second Modification This second modification is based on the configuration of the above embodiment, and further changes the configuration of the core and windings as shown in FIG.
That is, this 2nd modification changes the core 1 shown in FIG. 4 into the structure of the core 1a shown in FIG. 9, and besides the windings 2-4 shown in FIG. 4 according to this change of the core 1a, Windings 2b, 3b and 4b were added.
As shown in FIG. 9A, the core 1a includes three leg portions 101 to 103, connecting portions 104 and 105 connected to upper and lower ends of the three leg portions 101 to 103, and a leg portion 101. A connecting portion 106 that connects the central portions of the leg portions 102 and a connecting portion 107 that connects the central portions of the leg portions 102 and 103 are provided, and four windows 108 to 111 are formed.

As shown in FIG. 9B, windings 2 to 4 are wound around the lower end portions of the legs 101 to 103, respectively. Windings 2b to 4b are wound around the upper end portions of the leg portions 101 to 103, respectively.
The winding 2b includes a main winding 2b-1 and a secondary winding 2b-2, and these two windings are wound around the leg portion 101 of the core 1a. The winding 3b includes a main winding 3b-1 and a secondary winding 3b-2, and these two windings are wound around the legs 102 of the core 1a. Further, the winding 4b includes a main winding 4b-1 and a secondary winding 4b-2, and these two windings are wound around the leg portion 103 of the core 1a.

FIG. 10 is a connection example when the reactor device of the second modification is used as the starter 200 of the three-phase induction motor 100, and the windings 2 to 4 are respectively connected as shown. Further, the main windings 2b-1, 3b-1, 4b-1 of the windings 2b-4b and the secondary windings 2b-2, 3b-2, 4b-2 are respectively connected as illustrated.
In the circuit of FIG. 10, when starting the three-phase induction motor 100, the contactors SW1 to SW3 are closed while the contactors SW4 to SW9 of the starter 200 are open. Therefore, at the start of starting the three-phase induction motor 100, the main windings 2b-1, 3b-1, 4b-1 of the windings 2b-4b are connected in series to the windings 2-4, respectively. A series circuit is connected in series to the windings of the three-phase induction motor 100 and current flows.

  Thereafter, only the contactors SW7 to SW9 are closed while the contactors SW4 to SW6 are open. At this time, a current flows through the secondary winding 2b-2, and the magnetic fluxes of the main winding 2b-1 and the secondary winding 2b-2 cancel each other, thereby eliminating the reactance and equivalently shorting the primary side. It will be in the state. Such an operation is similarly performed between the main winding 3b-1 and the secondary winding 3b-2 and between the main winding 4b-1 and the secondary winding 4b-2.

For this reason, the reactance that limits the starting current is changed from the state in which the main windings 2b-1, 3b-1, and 4b-1 are connected in series to the windings 2 to 4, respectively. To change.
When the start is completed, the contactors SW4 to SW6 of the starter 200 are closed while the contactors SW1 to SW3 are closed. For this reason, after the start is completed, both ends of the series circuit of the coils are short-circuited by the contactors SW4 to SW6, and no current flows through the series circuit of the coils.

In this way, since the starting current is added in two stages according to the decrease in the starting current due to the increase in the number of revolutions at the time of starting, the starting is started with a low torque with little mechanical shock, and then the torque is appropriately adjusted. It has the effect of being added and being started smoothly. In order to obtain the same effect by combining conventional reactor starters, two reactor starters are required. In this modification, one is realized. In addition, no current flows through the windings 2 to 4 and the main windings 2 b-1, 3 b-1, 4 b-1 connected in series to the windings 2, 4, and 4 b-1 after the start-up. There is no concern about fever.
As described above, the switching of a large current during the start-up for the two-stage switching of the reactor on the primary side is made non-contact, and a start-up method in which no contactor surge that impairs the life of the device is generated is achieved.

(3) Third Modification This third modification is based on the configuration of the second modification shown in FIG. 9, and the windings 2 to 4 shown in FIG. 9 are replaced with the windings 2c to 4c as shown in FIG. It has been changed to.
The winding 2c includes a main winding 2c-1 and a secondary winding 2c-2, and these two windings are wound around the leg portion 101 of the core 1a. The winding 3c includes a main winding 3c-1 and a secondary winding 3c-2, and these two windings are wound around the legs 102 of the core 1a. Further, the winding 4c includes a main winding 4c-1 and a secondary winding 4c-2, and these two windings are wound around the leg portion 103 of the core 1a.

  FIG. 12 is a connection example when the reactor device of the third modification is used as the starter 200 of the three-phase induction motor 100, and the main windings 2b-1, 3b-1, 4b-1 and secondary windings 2b-2, 3b-2, 4b-2 are connected as shown in the figure. Further, the main windings 2c-1, 3c-1, 4c-1 of the windings 2c to 4c and the secondary windings 2c-2, 3c-2, 4c-2 are respectively connected as illustrated.

  In the circuit of FIG. 12, when starting the three-phase induction motor 100, the contactors SW1 to SW3 are closed while the contactors SW7 to SW12 of the starter 200 are open. For this reason, when starting the three-phase induction motor 100, the main windings 2c-1, 3c-1, 4c-1 are connected in series to the main windings 2b-1, 3b-1, 4b-1, respectively. These series circuits are connected in series to the windings of the three-phase induction motor 100, and a current flows.

  Thereafter, only the contactors SW7 to SW9 are closed while the contactors SW10 to SW12 are open. At this time, a current flows through the secondary winding 2b-2, and the magnetic fluxes of the main winding 2b-1 and the secondary winding 2b-2 cancel each other, thereby eliminating the reactance and equivalently shorting the primary side. It will be in the state. Such an operation is similarly performed between the main winding 3b-1 and the secondary winding 3b-2 and between the main winding 4b-1 and the secondary winding 4b-2.

For this reason, the starting current is limited from the state in which the main windings 2c-1, 3c-1, 4c-1 are connected in series to the main windings 2b-1, 3b-1, 4b-1, respectively. The state changes to only the windings 2c-1, 3c-1, and 4c-1.
When the start-up is completed, the contactors SW10 to SW12 are closed while the contactors SW1 to SW3 are closed. At this time, a current flows through the secondary winding 2c-2, and the magnetic fluxes of the main winding 2c-1 and the secondary winding 2c-2 cancel each other, thereby eliminating the reactance and short-circuiting the primary side equivalently. It will be in the state. Such an operation is similarly performed between the main winding 3c-1 and the secondary winding 3c-2 and between the main winding 4c-1 and the secondary winding 4c-2.

For this reason, the main windings 2b-1, 3b-1, 4b-1 and the main windings 2c-1, 3c-1, 4c-1 function as reactance when the three-phase induction motor 100 is started, but the start is completed. Since all the coils are later short-circuited on the secondary side, all the primary sides of the coils are demagnetized and no magnetic flux exists, and are equivalently short-circuited and lose their reactance function.
In this way, since the starting current is added in two stages in accordance with the decrease in the starting current due to the increase in the rotational speed at the time of starting, the engine is started with a low torque with little mechanical shock, and the torque is applied from the middle. There is an effect of starting smoothly. In addition, after the start is finished, the main windings 2b-1, 3b-1, 4b-1 and the main windings 2c-1, 3c-1, 4c-1 are loaded with motor operating current (rated or lower). Although a current flows, the secondary side of each reactor is short-circuited. As a result, the primary side is demagnetized and there is almost no magnetic flux, so there is no fear of heat generation due to iron loss.

As a result, the effect of eliminating the need for an external short-circuit contactor can be obtained. In the case of high pressure, since the contactor is large, the space merit becomes large.
As described above, a non-contact state is achieved for the two-stage switching of the reactor on the primary side, and a starting system that does not generate a contactor surge that impairs the life of the device is achieved.

(4) Fourth Modification As shown in FIG. 8, in the first modification, each of the windings 2a, 3a, and 4a includes a main winding and a secondary winding, which are shown in FIG. 13 (A). Such an insulating reactance demagnetization circuit 300 is configured.
The fourth modification is based on the configuration of the first modification, and connects the main and secondary windings of the windings 2a, 3a, and 4a in FIG. 8 as shown in FIG. 13 (B). The in-phase type reactance demagnetization circuit 400 is replaced. In this case, the secondary winding is a reverse winding.
With this configuration, during the degaussing operation, the reactance is made non-inductive and the reactor drop voltage is short-circuited equivalently in the same way as in the first modified example. Further, the effect of downsizing the contactor can be obtained.

(5) Fifth Modification As shown in FIG. 10, in the second modification, each of the windings 2b, 3b, 4b is composed of a main winding and a secondary winding, and these are shown in FIG. 13 (A). Such an insulating reactance demagnetization circuit 300 is configured.
The fifth modification is based on the configuration of the second modification, and connects the main and secondary windings of the windings 2b, 3b, and 4b of FIG. 10 as shown in FIG. 13 (B). The in-phase type reactance demagnetization circuit 400 is replaced. In this case, the secondary winding is a reverse winding.
With this configuration, during the degaussing operation, the reactance is made non-inductive and the reactor drop voltage is short-circuited equivalently in the same way as in the second modified example. Further, the effect of downsizing the contactor can be obtained.

(6) Sixth Modification As shown in FIG. 12, in the third modification, each of the windings 2b, 3b, 4b and the windings 2c, 3c, 4c comprises a main winding and a secondary winding. Is configured to form an insulating reactance demagnetization circuit 300 as shown in FIG.
The sixth modification is based on the configuration of the third modification. The main and secondary windings of the windings 2b, 3b, and 4b and the windings 2c, 3c, and 4c in FIG. As shown in B), the in-phase type reactance degaussing circuit 400 is connected and replaced. In this case, the secondary winding is a reverse winding.
With this configuration, during the degaussing operation, the reactance is made non-inductive and the reactor drop voltage is equivalently short-circuited as in the third modified example, so that the surge voltage suppression effect is achieved as in the third modified example. Further, the effect of downsizing the contactor can be obtained.

DESCRIPTION OF SYMBOLS 1, 1a ... Core 2-4, 2a-4a, 2b-4b, 2c-4c ... Winding | winding 5, 6 ... Frame 11-13, 101-103 ... Leg part 14,15, 104-107 ... connection part 16, 17, 108-111 ... window

Claims (6)

In the reactor device that starts the induction motor,
An inner iron type core comprising three leg portions and two connecting portions integrally connected to both end sides of the three leg portions, and configured by stacking steel plates;
Three windings wound around each of the three legs,
The core is configured not to provide a gap,
In addition, the strength of the magnetic field in the core is in a range of 500 [AT / cm] or more and 1200 [AT / cm] or less, and the size of the core is determined so as to be in the range. Features a reactor device. When viewed from the front, the plane, and the side, the core has a rectangular outer shape, the height of the outer shape is H, the length of the outer shape is L, and the core has a width of W and a thickness. Forming a magnetic path consisting of T
The height H of the outer shape is not less than 1.25 times and not more than 2.5 times the length L of the outer shape, and the thickness T of the magnetic path is 0.6 of the width W of the magnetic path. The reactor device according to claim 1, wherein the reactor device is not less than twice and not more than 1.4 times. The core has two windows that penetrate in the thickness direction at the left and right positions in the center of the front, and that the vertical length of the opening is a and the horizontal length is b,
The vertical length a of the openings of the two windows is 1.1 times or more and 3.4 times or less of the horizontal length b. Reactor device. Two rectangular frames sandwiching the steel plates to be laminated from the thickness direction;
Two first connecting screws for connecting the upper ends of the two rectangular frames to each other and fastening the steel plate from the thickness direction;
Two second connecting screws for connecting the lower ends of the two rectangular frames to each other and fastening the steel plate from the thickness direction;
The reactor device according to any one of claims 1 to 3, further comprising:   The reactor according to any one of claims 1 to 4, wherein the core has substantially the same cross-sectional area as each of the three leg portions and the two connecting portions. apparatus. Each of the three windings consists of a main winding and a secondary winding,
The reactor device according to claim 1, wherein each of the main winding and the secondary winding is wound around the leg portion.

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