JP2000021662A - Three-phase integrated current transformer - Google Patents

Abstract

(57) [Problem] To improve the accuracy of a measured value with respect to a genuine value when a current flowing through a circuit is small at normal times while maintaining small size and light weight. SOLUTION: A core 38, a secondary coil 37 wound around the core, and a primary coil 36 wound around the secondary coil 37 a plurality of times are provided in a first phase and a third phase. The coating was integrally molded. As a result, the ampere-turn of the primary coil 36 increases, and the accuracy of the measurement value by the secondary coil 37 improves in proportion to the square of the primary coil 36. Therefore, even when the current flowing through the circuit is small at normal times, Thus, it is possible to obtain high accuracy of the measured value with respect to the true value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-phase integrated current transformer having current transformer elements in at least two of the first to third phases.

[0002]

2. Description of the Related Art Conventionally, a current transformer housed in a switch device such as a control center is for activating a protective relay and tripping a circuit breaker when an accident such as a short circuit occurs. , Are connected to a unit device (unit) having those devices.

FIG. 10 specifically shows a conventional structure of such a current transformer. In this device, an iron core 1, a secondary coil 2 wound around the iron core 1, secondary terminals 3 and 4 connected to a winding start end 2a and a winding end end 2b of the secondary coil 2, respectively. Are provided in the first and third phases,
These are integrally covered and molded with a mold material generally made of a synthetic resin to form a mold portion 5.

[0004] A window 6 is formed in the mold portion 5 and located inward of each secondary coil 2 and penetrates in the axial direction. A window 7 penetrating in the direction is formed. The primary connection conductors 8 provided in the first phase, the second phase, and the third phase are inserted into the windows 6 and 7, respectively. It is fixed to the mold part 5 by the mounting screw 10.

[0005] Although not shown, the primary connection conductor 8 is connected at one end to a conductor derived from the unit device, and at the other end to a cable for supplying power to an external device. . With this configuration, when an accident such as a short circuit occurs, the accident current flows through the primary connection conductor 8, and a current proportional to the accident flows through the secondary coil 2, and the protection relay is operated by the current as described above, It is designed to trip the circuit breaker.

[0006]

The above-mentioned current transformer responds to an accident such as a short circuit as described above, but is also used to monitor a current flowing in a circuit in a normal state.
In this case, a current proportional to the normal current flowing through the primary connection conductor 8 flows through the secondary coil 2, and the monitoring device is operated by the current.

In such a function, if the current flowing through the circuit is small, the current flowing through the current transformer is also small. On the other hand, the primary connection conductor 8 combined with the secondary coil 2 of the conventional current transformer is inserted into a window 6 formed inside the secondary coil 2 and Since it only penetrates, the ampere-turn which is the product of the number of turns of the conductor and the current flowing through the conductor is small, and the accuracy of the measured value (current value) by the secondary coil 2 with respect to the true value is inferior. Was.

In this case, in order to improve the accuracy, it is conceivable to increase the sectional area of the iron core 1 so that the magnetic flux generated by the current flowing through the primary coil flows easily. However, in order to store the current transformer in the above-described switch device or the like, the size and weight are limited, and the cross-sectional area of the iron core 1 cannot be increased.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is therefore an object of the present invention to maintain the small size and light weight and to obtain the accuracy of the measured value with respect to the true value when the current flowing through the circuit is small at normal times. To provide a three-phase integrated current transformer with a high cost.

[0010]

In order to achieve the above object, a three-phase integrated current transformer according to the present invention comprises, first, an iron core and a two-phase current transformer. A secondary coil wound around the iron core, and a primary coil wound a plurality of times around the secondary coil, and are integrally coated and molded with a molding material.

According to this, the primary coil is wound around the secondary coil a plurality of times, so that the ampere-turn of the primary coil is increased. Since the accuracy of the measured value of the secondary coil with respect to this ampere turn improves in proportion to the square of the measured value, even when the current flowing through the circuit is small at normal times, the measured value with respect to the true value is small. It is possible to obtain high accuracy. In this case, the iron core does not need to have a large sectional area.

Secondly, the three-phase integrated current transformer of the present invention comprises a secondary coil wound around a bobbin in two phases of the first to third phases, and the secondary coil And a primary coil wound concentrically a plurality of times, and integrally molded with a molding material, and a window portion which is located inside the secondary coil and penetrates in the axial direction is formed in the molded portion. It is characterized in that the split core is assembled by inserting one leg of the split core into the window and positioning the other leg outside the mold portion.

According to this method, the primary coil is wound around the secondary coil a plurality of times, so that the ampere-turn of the primary coil is increased. Can be obtained with high accuracy. Also in this case, the iron core does not need to have a large sectional area.

In addition, in the iron core assembled by inserting one leg into the window of the mold part, since most of the other parts are located outside the mold part, the mold part is partially removed from the periphery of the iron core. It has the same form, which allows further reduction in size and weight. Further, since the iron core and the mold portion do not come into close contact with each other, cracks due to the difference in thermal expansion do not occur in the mold portion, and a cushion material for preventing the cracks is not required.

Third, the three-phase integrated current transformer according to the present invention comprises, in a third aspect, a secondary coil wound around a bobbin in two of the first to third phases, and the secondary coil And a primary coil wound concentrically a plurality of times, and integrally molded with a molding material, and penetrated in the molded portion inward and outward of the secondary coil in the axial direction, respectively. The split iron core is formed by inserting one of the leg portions and the other leg portion of the split core into both of the window portions.

According to this method, the primary coil is wound around the secondary coil a plurality of times, so that the ampere-turn of the primary coil is increased. Can be obtained with high accuracy. Also in this case, the iron core does not need to have a large sectional area.

In addition, since the iron core in which one leg and the other leg are inserted into the two windows of the mold portion and assembled is located, many other portions are located outside the mold portion. This is the same form as removing the mold part from the surrounding part.In addition, in this case, the mold part can only be used to cover the secondary coil and the primary coil, so that the mold part can be further reduced. Therefore, the size and weight can be further reduced. Further, since the iron core and the mold portion do not come into close contact with each other, cracks due to their thermal expansion difference do not occur in the mold portion, and a cushion material for preventing the cracks is not required.

Fourthly, the three-phase integrated current transformer of the present invention has four phases, instead of two of the first to third phases.
It is characterized by comprising a secondary coil and a primary coil wound around the secondary coil a plurality of times. According to this, in a three-current transformer structure having a current transformer element in all of the first to third phases, the first, second, or third three-phase integrated current transformer is provided. The same effect can be obtained.

Fifthly, the three-phase integrated current transformer of the present invention comprises a secondary coil, a primary coil wound around the secondary coil a plurality of times, and a primary connection conductor to which the primary coil is connected. A unit current transformer having a mounting member, and a unitary current transformer having a mounting member, and a primary connecting conductor integrally covering and molding with a molding material, comprising a spacer having a mounting member, and selectively combining these. It is characterized by three phases integrated.

According to this, at least the same operation and effects as those of the first three-phase integrated current transformer can be obtained, and in addition, the current transformer element is connected to two of the first to third phases. From a two-current transformer structure having a current transformer element to a three-current transformer structure having current transformer elements in all of the first to third phases, or from the three-current transformer structure to the two-current transformer structure. Changes are possible depending on the combination of the unit current transformer and the spacer.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. First, FIG. 3 shows the overall configuration of a switch device, for example, a control center 21, in which a control room 25 and a cable room 26 are arranged in a housing 24 having doors 22 and 23 on both front and rear sides. It is formed separately. Inside the control room 25,
At the uppermost part, horizontal buses 27 for three phases are arranged in front and rear, and vertical buses 28 for three phases are similarly arranged in right and left at the rear, and these are connected by connection conductors 29 respectively.

A plurality of unit chambers 30, for example, three steps, are formed vertically in a portion of the control room 25 ahead of the vertical bus 28, and each unit room 30 has a unit device (unit). 31 is provided so that it can be taken in and out. Although not shown in detail, the unit device 31 has a main circuit control device such as a protective relay or a circuit breaker, and further has a monitoring device such as a display device,
Each of the vertical buses 28 is connected by a connection device 32.

On the other hand, the current transformer 33 is connected to the connecting device 3.
2, likewise, it is arranged between each unit room 30 and the vertical bus 28, and more specifically, is connected between a conductor 34 derived from the unit device 31 and a cable 35 arranged in the cable room 26. It is provided. The cable 35 is composed of the horizontal bus 27 to the vertical bus 28, the connecting device 32, the unit 3
1. The power supplied through the current transformer 33 in order is further supplied to an external device (not shown).

FIG. 1 shows the configuration of the current transformer 33 in detail. In FIG. 1, reference numeral 36 denotes a primary coil, 3
Reference numeral 7 denotes a secondary coil, of which the secondary coil 3
Numeral 7 is wound in a toroidal shape around an annular iron core 38, and secondary terminals 39 and 40 are connected to its winding start end 37a and winding end end 37b, respectively. On the other hand, the primary coil 36 is wound a plurality of times around one part (the lower part in the figure) around the secondary coil 37, and FIG. 2 shows the structure.

That is, the primary coil 36 passes through the center of the secondary coil 37 from the left side of the secondary coil 37 in FIG. 2 and the winding is performed so as to reach the right side in FIG. 2. The turn (turn) of the primary coil 36 with respect to the secondary coil 37 is the number of turns that have passed inside the center side of the secondary coil 37. In this case, since the primary coil 36 passes twice inside the center side of the secondary coil 37, the number of turns of the primary coil 36 with respect to the secondary coil 37 is two. The coil 36 is wound twice at one location around the secondary coil 37. Touch, secondary coil 3
The number of turns of the primary coil 36 with respect to 7 may be a plurality of times, and is not limited to two times, but three times, four times,.
The number may be increased.

The primary connection conductors 41 and 42 are respectively connected to the winding start end 36a and the winding end end 36b of the primary coil 36.
Are connected. In this state, the primary coil 36, the primary connection conductors 41 and 42, the secondary coil 37, and the iron core 38 are provided in a first phase and a third phase (left and right in the figure) as shown in FIG. In the center of the figure, a single primary connection conductor 43 is provided, and these are integrally covered and molded with a molding material made of a synthetic resin such as an epoxy resin having excellent properties such as insulation and flame retardancy. 44 are formed.

In this case, the secondary terminals 39 and 40 are arranged below the primary connection conductor 43, and
9 and 40, the respective ends of the primary connection conductors 41 and 42, and both ends of the primary connection conductor 43
4 Exposed outside.

Further, mounting bosses 45 having concave portions 45a at the end surfaces thereof are disposed at one diagonal position (lower left and upper right portions in the figure) on both left and right end surfaces of the mold portion 44, and are covered and molded. 46 is molded at the other diagonal position (upper left and lower right in the figure). These mounting bosses 45
And the supporting projections 46 are mounting members for the current transformers 33, whereby the current transformers 33 are fixed on both sides between the unit chambers 30 and the vertical bus 28 (not shown).
And the current transformer 33 is fixed.

The attachment boss 45 and the support projection 46 are attached to the fixing member by, for example, fitting the recess 45a of the attachment boss 45 to the projection of the fixing member.
The support protrusions 46 are fitted into recesses of the fixing member, and the molded portion 44 is further screwed to the fixing member, for example, so that they do not come off.

The conductor 3 derived from the unit 31
4, the end of each primary connection conductor 41 is connected to the first and third phase conductors 34, and one end of the primary connection conductor 43 is connected to the second phase conductor 34. Further, for the cable 35, the distal end of each primary connection conductor 42 is connected to the first and third phase cables 35, and the primary connection conductor 43 is connected.
Is connected to the second-phase cable 35. Each of the secondary terminals 39 and 40 is connected to a main circuit control device and a monitoring device of the unit device 31.

Next, the operation of the above configuration will be described. When the external device connected to the cable 35 is energized, the energizing current flows through the primary coil 36 of the current transformer 33, and a current proportional thereto flows through the secondary coil 37. Therefore, when an accident such as a short circuit occurs, the accident current flows through the primary coil 36, and a current proportional to the accident current flows through the secondary coil 3.
7, the main circuit control device of the unit device 31, for example, a protection relay is activated by this current, and the circuit breaker trips.

Further, even in a normal state, a current proportional to the current flowing through the primary coil 36 flows through the secondary coil 37, and the monitoring device of the unit device 31, for example, a display is operated by the current. I have.

In this function, in the current transformer 33, the primary coil 36 is wound around the secondary coil 37 a plurality of times, thereby increasing the ampere-turn of the primary coil 36. For this ampere turn, the secondary coil 3
7, the accuracy of the measured value is improved in proportion to the square of the measured value. Thus, even when the current flowing through the circuit is small at normal times, the accuracy of the measured value with respect to the true value is increased. As a result, measurement accuracy can be improved. Also, in this case, the iron core 38 does not need to have a large cross-sectional area, so that it can be kept small and lightweight.

4 to 9 show the second to seventh embodiments of the present invention. The same parts as those in the first embodiment are denoted by the same reference numerals, and the description will be made. Omitted, and only different parts will be described.

[Second Embodiment] In the second embodiment shown in FIG. 4, the secondary coil 37 and the primary coil 3 of the first embodiment are used.
6, a secondary coil 52 wound around a winding frame 51 and a primary coil 53 wound concentrically around the secondary coil 52 a plurality of times are provided. The winding start end 52a and the winding end end 52b of the secondary coil 52 are connected. Further, the winding start end 53a and the winding end end 53b of the primary coil 53 are connected to the primary connection conductors 41 and 42, respectively.

In this state, the primary coil 53, the primary connection conductors 41 and 42, the winding frame 51, and the secondary coil 52 are provided in the first and third phases, and the primary connection conductor 43 is provided in the second phase.
Then, they are integrally covered and molded with the same molding material as described above to form a molded portion 54. Note that, in this case, the primary connection conductors 41 and 42 and the primary connection conductor 43 are arranged above the molded portion 54. As described above, the mounting bosses 45 are disposed on the left and right end surfaces of the mold portion 54 to cover and mold the support protrusions 4.
6 is formed by molding.

Further, a window portion 55 is formed in the mold portion 54 so as to be located inward of each secondary coil 52 (the winding frame 51) and penetrate in the axial direction.
Is a split iron core divided into a plurality of pieces such as two C-shapes. One of the split iron cores 56a is inserted into the window 55, and the other leg 56b is positioned below the outside of the mold 54 and assembled. In addition, for the iron core 56 thus assembled,
The mold 54 further includes a pair of protrusions 57 sandwiching the other leg 56 b of the iron core 56, and a core fixing plate 58 is passed between the respective tips of the protrusions 57 so that screws 59 are formed.
And the iron core 56 is fixed.

Also in this case, the primary coil 53 is wound around the secondary coil 52 a plurality of times so that the primary coil 53 is wound.
Therefore, as described above, even when the current flowing through the circuit is small at the normal time, the accuracy of the measurement value with respect to the genuine value can be increased, thereby improving the measurement accuracy. be able to. Also in this case, the iron core 56 does not need to have an unnecessarily large cross-sectional area, and thus can be kept small and lightweight.

Moreover, the iron core 56 is assembled by inserting one leg 56a into the window 55 of the mold 54.
Since many other parts are located outside the mold part 54,
This is the same form as the conventional one in which the mold part 5 is partially removed from the peripheral part of the iron core 1, so that the size and weight can be further reduced. By the way, in this case, in actual measurement, the size was reduced by about 20 [%] and the size was reduced by about 30 [%] as compared with the conventional one.
It has been found that weight reduction is possible.

Further, in this case, the iron core 56 and the mold portion 54 do not come into close contact with each other. Accordingly, cracks due to the difference in thermal expansion do not occur in the mold portion 54, and a cushion material for preventing the cracks can be eliminated.

[Third Embodiment] In a third embodiment shown in FIG. 5, a winding frame 51 and a secondary coil 5 of the structure of the second embodiment are used.
2 and the primary coil 53, a window portion 55 is formed in the mold portion 54 so as to be located inward of each of the secondary coils 52 (the bobbin 51) and penetrate in the axial direction, and the outside portion thereof is formed. Window part 61 which is also located in the axial direction
The one leg portion 56a and the other leg portion 56b of the split iron core 56 are inserted into the window portions 55 and 61 and assembled.

Also in this case, by increasing the ampere-turn of the primary coil 53, the accuracy of the measured value with respect to the genuine value can be increased, and in addition, many parts of the iron core 56 are located outside the mold portion 54. Therefore, the configuration is the same as that of the conventional iron core 1 in which the mold portion 5 is partially removed from the periphery. In addition, in this case, the mold 54 may only cover the secondary coil 52 and the primary coil 53,
Since even the protrusion 57 of the second embodiment is not necessary, the mold 54 can be further reduced.
The size and weight can be further reduced. By the way, in this case, the actual measurement is about 30 times smaller than the conventional one.
It has been found that [%] can be reduced in size and about 35 [%] can be reduced in weight.

Further, even in this case, since the iron core 56 and the mold portion 54 do not come into close contact with each other, a crack due to a difference in thermal expansion between the core portion 56 and the mold portion 54 does not occur in the mold portion 54. Materials can be made unnecessary.

[Fourth Embodiment] In the fourth embodiment shown in FIG. 6, in addition to the above-described first and third phases, a second phase is also provided.
The structure of the iron core 38, the secondary coil 37, and the primary coil 36 of the first embodiment is provided, and these are integrally covered and molded by the molding material forming the molding portion 44. According to this, in a three-current transformer structure having current transformer elements in all of the first to third phases, the same operation and effect as in the first embodiment can be obtained.

[Fifth Embodiment] In a fifth embodiment shown in FIG. 7, the structure of the winding frame 51, the secondary coil 52 and the primary coil 53 of the second embodiment is different from the first phase, the second phase, and the second phase. It is provided for all of the third phases, and these are integrally covered and molded by the molding material forming the molding portion 54. And like the first phase and the second phase, the secondary coil 52 of the second phase
One leg 56a of the split iron core 56 is inserted into and fixed to a window 55 formed in the mold portion 54 located inside the (winding frame 51).

In this case, the same operation and effect as in the second embodiment can be obtained in a three-current transformer structure having current transformer elements in all the first to third phases. In this case, by assembling the iron core 56 with the same structure as that of the third embodiment, the same operation and effect as those of the third embodiment can be obtained by changing the current transformer elements to all the first to third phases. Can be obtained in a three-current transformer structure having

[Sixth Embodiment] The sixth embodiment shown in FIG. 8 includes a unit current transformer 71 and a spacer 72, of which the unit current transformer 71 is the iron core of the first embodiment. 38, the secondary coil 37, the primary coil 36, the primary connection conductors 41 and 42, and the secondary terminals 39 and 40 are integrally covered and molded with a molding material similar to that described above to form a molded portion 73. A flow device 71 is formed, and a mold portion 73 has a mounting boss 45 and a support protrusion 46 on both left and right sides.

On the other hand, the spacer 72 is formed by the primary connection conductor 43.
Is formed by integrally coating and molding with a molding material similar to that described above to form a molded portion 74, and the molded portion 74 also has mounting bosses 45 and support protrusions 46 on both left and right sides. .

In this case, however, the unit current transformer 71
And three spacers 72 to form a three-phase unit. For example, by combining two unit current transformers 71 and one spacer 72, the first and third phases are the same as in the first embodiment. A three-phase integrated current transformer having a two-current transformer structure having a current transformer element is obtained. Further, by combining three unit current transformers 71, a current transformer element is provided in all of the first to third phases as in the fourth embodiment.
A three-phase integrated current transformer having a current transformer structure can be obtained. The three-current transformer structure can be changed from the above-described two-current transformer structure, and vice versa. Can be changed to the two-current transformer structure described above.

The combination of the unit current transformer 71 and the spacer 72 or the combination of the unit current transformers 71 is as follows.
The mounting bosses 45 are fixed to each other by fitting the mounting bosses 45 to the support projections 46 on the other side. Therefore, in this case,
In addition to obtaining the same operation and effect as the first embodiment, the specification of the current transformer structure is changed by changing the unit current transformer 71 and the spacer 72.
It becomes possible depending on the combination with the above, and it is possible to standardize parts for the difference in the specification of the current transformer structure.

[Seventh Embodiment] The seventh embodiment shown in FIG. 9 includes a unit current transformer 81 and a spacer 82, of which the unit current transformer 81 is the same as that of the second embodiment. The frame 51, the secondary coil 52, the primary coil 53, the primary connection conductors 41 and 42, and the secondary terminals 39 and 40 are integrally covered and molded with the same molding material as described above to form a molded portion 83. Then, this mold part 83
A window 55 is formed inside the secondary coil 52 (the winding frame 51), and one leg 56a of the split core 56 is inserted into the window 55 and fixed. The unit 8 constitutes a unit current transformer 81,
3 has a mounting boss 45 and a support protrusion 46 on both left and right sides.

On the other hand, the spacer 82
Are integrally molded with the same molding material as described above to form a molded portion 84. The molded portion 74 also has mounting bosses 45 and support projections 46 on both left and right sides. .

In this case, however, the unit current transformer 81
As described above, for example, by combining two unit current transformers 81 and one spacer 82, the second
As in the embodiment, a three-phase integrated current transformer having a two-current transformer structure having current transformer elements in the first phase and the third phase is obtained. 3
By combining two unit current transformers 81, a three-phase integrated current transformer having a three-current transformer structure having current transformer elements in all of the first to third phases as in the fifth embodiment is obtained. It is possible to change from the above-mentioned two-current transformer structure to this three-current transformer structure, and vice versa, that is, to change from the three-current transformer structure to the above-mentioned two-current transformer structure. is there.

Therefore, in this case, in addition to obtaining the same operation and effect as the second embodiment, the specification of the current transformer structure can be changed depending on the combination of the unit current transformer 81 and the spacer 82. It is possible to standardize parts for the difference in the specifications of the current transformer structure. In this case as well, the combination of the unit current transformers 81 and the spacers 82 or the combination of the unit current transformers 81 depends on their mounting bosses 45.
Are fixed to each other by being fitted to the support projection 46 on the other side.

In this case, the iron core 56 is assembled in the same structure as that of the third embodiment, so that the parts can be standardized for the difference in the specification of the current transformer structure. The same operation and effect as in the third embodiment can be obtained. Then, the first embodiment to the third embodiment
In the embodiment, and the sixth and seventh embodiments,
Primary and secondary coils, iron cores, primary connection conductors, and secondary terminals are provided not in the first and third phases but in the first and second phases, or the second and third phases, and the remaining One phase may include only the primary connection conductor.

[0056]

The present invention is as described above.
The following effects are obtained. According to the three-phase integrated current transformer of the first aspect, it is possible to obtain high accuracy of the measured value with respect to the true value even when the current flowing through the circuit is small at normal time while maintaining small size and light weight. In addition, measurement accuracy can be improved.

According to the three-phase integrated current transformer of the second aspect, in addition to the same effects as the three-phase integrated current transformer of the first aspect, the size and weight can be further reduced, and the cracks in the mold portion can be reduced. It can even eliminate the need for a cushioning material for prevention.

According to the three-phase integrated current transformer of the third aspect, in addition to the same effects as the three-phase integrated current transformer of the first aspect, the size and weight can be further reduced, and cracks in the mold portion can be prevented. Can even eliminate the need for cushioning material.

According to the three-phase integrated current transformer of the fourth aspect, in the three-phase current transformer structure having the current transformer elements in all of the first to third phases, the first and second aspects of the present invention are described. Or claim 3
The same operation and effect as those of the three-phase integrated current transformer can be obtained.

According to the three-phase integrated current transformer of the fifth aspect, at least the same effects as those of the three-phase integrated current transformer of the first aspect can be obtained. Changes can be made easily, and parts can be standardized for differences in the specifications of the current transformer structure.

[Brief description of the drawings]

FIG. 1 is a longitudinal rear view of a current transformer alone showing a first embodiment of the present invention.

FIG. 2 is a longitudinal side view taken along line AA of FIG. 1;

FIG. 3 is a schematic longitudinal sectional side view of the entire device including a current transformer.

FIG. 4 is a view corresponding to FIG. 1 showing a second embodiment of the present invention.

FIG. 5 is a view corresponding to FIG. 1, showing a third embodiment of the present invention.

FIG. 6 is a view corresponding to FIG. 1, showing a fourth embodiment of the present invention;

FIG. 7 is a view corresponding to FIG. 1, showing a fifth embodiment of the present invention.

FIG. 8 is a view corresponding to FIG. 1 showing a sixth embodiment of the present invention.

FIG. 9 is a view corresponding to FIG. 1 showing a seventh embodiment of the present invention.

FIG. 10 is a diagram corresponding to FIG. 1 showing a conventional example.

[Explanation of symbols]

33 is a current transformer, 36 is a primary coil, 37 is a secondary coil,
38 is an iron core, 41 to 43 are primary connection conductors, 44 is a molded part, 45 is a mounting boss (mounting member), 46 is a support protrusion (mounting member), 51 is a winding frame, 52 is a secondary coil, and 53 is a primary coil. , 54 are a mold portion, 55 is a window portion, 56 is an iron core (divided iron core), 61 is a window portion, 71 is a unit current transformer, 72
Is a spacer, 73 and 74 are mold parts, 81 is a unit current transformer, 82 is a spacer, and 83 and 84 are mold parts.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Saburo Yoshida 2121, Nagoya, Asahimachi, Mie-gun, Mie Prefecture Inside Mie Plant, Toshiba Corporation (72) Inventor Yoshihiro Kamikawa 2121, Nagoya, Asahimachi, Mie-gun, Mie Prefecture (72) Inventor Kengo Yamanaka 2-24-24 Harumi-cho, Fuchu-shi, Tokyo F-term (reference) 5E043 BA01 5E044 AD03 AD06 BA03 BB01 BC02 5E081 AA05 BB03 CC05 DD05 DD12 DD17 DD25 EE01 EE14 EE18 FF04

Claims (5)

[Claims] 1. An iron core, a secondary coil wound around the iron core, and a primary coil wound around the secondary coil a plurality of times in two of the first to third phases. A three-phase integrated current transformer characterized by being integrally covered and molded with a molding material. 2. A secondary coil wound around a bobbin and a primary coil wound concentrically a plurality of times around the secondary coil in two of the first to third phases. In addition to integrally molding with a molding material, a window portion which is located inside the secondary coil and penetrates in the axial direction is formed in the molded portion. A three-phase integrated current transformer, wherein the current transformer is inserted into the window and the other leg is positioned outside the mold part. 3. A secondary coil wound around a bobbin and a primary coil wound concentrically around the secondary coil a plurality of times in two of the first to third phases. In addition to integrally covering and molding with a molding material, window portions are formed in the molded portion at the inner side and the outer side of the secondary coil and respectively penetrate in the axial direction. A three-phase integrated current transformer, wherein one of the legs and the other leg of the current transformer are inserted and assembled into both windows. 4. A method in which, instead of two phases of the first to third phases, all phases include a secondary coil and a primary coil wound around the secondary coil a plurality of times. The three-phase integrated current transformer according to any one of claims 1 to 3, wherein: 5. A secondary coil, a primary coil wound a plurality of times around the secondary coil, and a primary connection conductor to which the primary coil is connected are integrally covered and molded with a molding material, and a mounting member is provided. A three-phase integrated type, comprising: a unitary current transformer; and a spacer having a mounting member, in which the primary connection conductor is integrally covered and molded with a molding material, and these are selectively combined to form a three-phase integrated body. Current transformer.