JPH05328703A - Electromagnetic pump - Google Patents

Abstract

PURPOSE:To decrease space necessary for wiring to contrive to miniaturize an apparatus by reducing the number and length of power cable wired inside the apparatus. CONSTITUTION:In a three-phase induction electromagnetic pump in which a passage for causing a conductive fluid to flow is formed between outer duct and inner duct, wirings 20-25 between the lead wires of a plurality of in-phase coils constituting respective stator coils of the outer duct and inner duct are caused to diverge from a power cable 30 with the same phase as that of the coils to a plurality of parallel circuits and are connected in series by a conductive wire narrower than the power cable 30.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an annular linear type three-phase induction type electromagnetic pump, and particularly to a high temperature such as a coolant circulation pump in a liquid metal cooling type reactor using liquid metal as a coolant. The present invention relates to an electromagnetic pump used in the environment.

[0002]

2. Description of the Related Art An annular linear type electromagnetic pump has an annular cross section, which means that ALIP (Annular Li
It is called "Near Induction Pump" and has high duct structure reliability and safety, so it is suitable for large capacity reactor coolant circulation pump.

6 and 7 show the basic structure of a conventional ALIP. The ALIP is a concentric double pipe whose outer duct 1 and inner duct 2 are made of stainless steel, and an annulus passage 3 is formed between the ducts 1 and 2. Further, since ALIP has a circular duct shape and is excellent in strength, it can be said that it is a highly reliable duct.

An outer stator 4 and an inner stator 5 are provided on the outer side of the outer duct 1 and on the inner side of the inner duct 2, respectively, and these are comb-shaped iron cores 6, 7 as shown in FIG. 7B. , And ring-shaped coils 8 and 9.

The liquid sodium is the annulus flow path 3
Flowing in the direction shown by the arrow in FIG.
There are a one-through type in which sodium flows only in one direction and a center return pipe type in which the direction of sodium flow in the center return pipe 10 is reversed as shown in FIG. 6, but both types are common in the present invention. The center return pipe type will be described below.

Further, the capacity of the main circulation pump of a liquid metal cooled reactor falls within the range of several tens to two hundreds of tens m ³ / min. The double-stator type ALIP is most suitable because of the demand for high efficiency. Therefore, the double stator type ALIP will be described below.

As shown in FIG. 8, the coils 8 and 9 are formed in a ring shape having three lead wires 11, and the coil conductor wires 12 form three parallel circuits in the coil to form a coil. The ground voltage applied to one of the conductor wires 12 is reduced, and the load on the ground insulating material of the coil is reduced. Then, as shown in FIG. 8 (C), the coil conductor wires 12 are individually insulated by a composite inorganic insulating tape made of ceramic and mica to form a wire insulation portion 13, which is further wound on a ring and molded to form a ceramic material. The structure is insulated from the ground by the composite inorganic insulating tape 14 made of mica or the like.

The coils 8 and 9 are repeatedly arranged in the order of U-phase, V-phase and W-phase, and a progressive magnetic field is generated by passing a three-phase alternating current through each of these phases. When it is made to pass through the duct, a voltage is induced in the liquid sodium and an induced current flows. The induced current and a part of the component of the traveling magnetic field act to generate an electromagnetic force, and the electromagnetic force generates a thrust.

Next, a method of connecting the coils will be described.

In a small capacity pump having a rated current of about 1 m ³ / min, a single stator type having only the outer stator 4 and the inner stator 5 having only the iron core is suitable. The voltage between the terminals of the electromagnetic pump is about several hundreds of volts, but the breakdown voltage of the coil against ground insulation is about several KV in the environment when the pump is rated, so the tolerance to ground insulation is high. For this reason,
The lead wires 11 of the same phase can be connected in series.

That is, FIG. 9 shows an example of inter-coil wiring of a small capacity pump (1 pole 3 coils, 4 poles configuration). In the case of this small capacity pump, since the operating voltage is low, the U phase, V
It is sufficient to use only nine systems, which are three systems of the phase and W phase and three systems of the wiring 15 between the lead wires of the coil. Further, the current flowing through these wires is about 100 amps in the power cable 16 and about 30 amps in the wiring 15 between the lead wires of the coil, so the required cross-sectional area is 0.6 c for the power cable 16.
m ² and the wiring 15 between the lead wires of the coil may be about 0.1 cm ² .

For this reason, the power supply cable 16 and the wiring 15 between the lead wires of the coil are routed in such a manner that three power supply cables 16 each having a cross-sectional area of 0.6 cm ² are drawn from the upper part of the pump to the inside and above the stator part 17. After separating into the inter-lead wire 15 of the coil having a cross-sectional area of 0.1 cm ² of each phase 3 system, it descends while connecting the lead wires of the same phase in series, and connects the lowest coil of each phase. Later, a method was adopted in which all wiring was short-circuited (becomes a neutral point).

Therefore, since the wiring space for these wirings has a small thickness of the power cable 16 and the wiring 15 between the coil lead wires, and the number of parallel circuits is small, there is a sufficient margin for the space inside the pump. It was

[0014]

By the way, in order to increase the capacity of the electromagnetic pump, it is necessary to increase the input voltage and the input current. On the other hand, due to the requirement of coil insulation, the voltage applied to the ground insulation of the coil should be minimized. Since it is necessary to reduce the size, it is necessary to use delta connection for the coil connection method and to reduce the voltage applied to the coil insulation by using a parallel circuit in many wirings.

For example, the ground voltage of a large capacity electromagnetic pump used for the primary main circulation pump of the fast breeder reactor shown in FIGS. In consideration of the margin of, it is necessary to divide the wiring between the coil lead wires into a plurality of parallel circuits.

From this point of view, in the large capacity electromagnetic pump, one stator is connected to two parallel circuits, that is, the outer stator 4.
A double stator type in which the inner stator 5 is divided and configured is suitable. Here, the inner stator wiring and the outer stator wiring are assembled in parallel delta connection in order to reduce the ground voltage.

However, as a result, the total number of parallel circuits arranged inside the pump is 3 (3 phases) × 3 (parallel circuit connected to the three lead wires of each coil) × 2 (the wiring between the coil lead wires is as described above). Divided into two parallel circuits) x 2
(Inner and outer stators) = 36 parallel circuits, which is enormous.

Further, in the large capacity electromagnetic pump, since a current of about 4000 amperes must be passed through the power cable, the cross-sectional area of the conductor wire of the power cable is about 9 cm ² , and the cross-sectional area of the wire between the coil lead wires is 0. Approximately 0.8 cm ^{2 is} required, and considering the number of wires in the above 36 systems, it is expected that the volume required for the wiring facility will be considerably large.

By the way, there is a demand for downsizing the electromagnetic pump in order to make the equipment installation area of the fast reactor as small as possible. Due to the structure of the inner stator 5, the space for wiring can be particularly narrow, and the reactor cooling As a result of installing a considerable number of stator supports 18 shown in FIG. 7 (A) inside the pump due to seismic requirements as system equipment, it is expected that the pump void volume ratio will decrease. Therefore, it has been necessary to create a rational coil wiring method and reduce the volume required for wiring.

The present invention has been made in consideration of the above-mentioned circumstances. By reducing the number and length of power cables internally wired, the space required for wiring is reduced and the size is reduced. It is intended to provide an electromagnetic pump.

[0021]

In order to solve the above-mentioned problems, an electromagnetic pump according to the present invention is of a three-phase induction type in which a flow path for flowing a conductive fluid is formed between an outer duct and an inner duct. In the electromagnetic pump, the wiring between lead wires of a plurality of coils of the same phase forming each stator coil of the outer duct and the inner duct is branched from a power cable of the same phase as the coil into a plurality of parallel circuits, It is connected in series with a thin conductive wire.

[0022]

In the present invention having the above structure, the wiring between the lead wires of a plurality of coils of the same phase forming each stator coil of the outer duct and the inner duct is branched from the power cable of the same phase as the coils into a plurality of parallel circuits. In addition, since the power cables are connected in series by a conductive wire thinner than the power cables, the number and length of power cables to be wired inside are reduced, and as a result, the internal wiring space can be narrowed.

[0023]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 3 shows the overall construction of an embodiment of the electromagnetic pump according to the present invention. It should be noted that the same or corresponding portions as those of the conventional configuration will be described with the same reference numerals as those in FIG.

As shown in FIG. 3, the electromagnetic pump of this embodiment is of a three-phase induction type, and has a concentric double pipe structure of an outer duct 1 and an inner duct 2 for flowing a conductive fluid such as liquid metal sodium. The annulus flow path 3 is formed by. An outer stator 4 is provided outside the outer duct 1, and an inner stator 5 is provided inside the inner duct 2.

FIG. 1 (A) shows a coil wiring diagram of the outer stator 4 of the large capacity electromagnetic pump of the flow rate 200 ³ / min class. Here, an electromagnetic pump having 144 stator coils in the outer duct 1 and the inner duct 2 will be described. Further, in FIG. 1 (A), only the U phase is taken out and shown, but the wiring modes are the same except for the coil numbers for connecting the V and W phases as well. The phases are connected by delta connection.

Then, wirings 21, 21 and 2 between lead wires of a plurality of U-phase coils forming the coils of the outer stator 4 are formed.
2, 23, 24, and 25 branch from the power cable 30 in the same phase as the coil into six parallel circuits, and are connected in series by conductive wires thinner than the power cable 30.

That is, the U-phase power supply cable 30 is drawn in from the upper part of the pump, and the six parallel coil lead-out wire lines 20, 21, 22, 23, 2 above the outer stator 4.
It is branched to 4, 25.

The wiring 20 between the coil lead wires is the coil number 1, 13, 25, 12 × (n-
1) + 1st, ..., 121th, 133th coil lead wires 40 are connected in series while descending, and then connected to 135th coil lead wire 40, from which 123th, ..., 12
× (n-1) +3, ..., 15 and 3, rising along the stator 4 and other coil lead wire 21 ', 22
′, 23 ′, 24 ′ and 25 ′ are connected to the power cable 30 ′ at the upper part of the outer stator 4 and drawn out from the upper part of the pump.

Wiring 21 between coil lead wires which is parallel wiring
The coil number 6 × (n−
1) descend while connecting the +2 coil in series, 134
After being connected to No. 137 coil, connected to No. 137 coil,
Next, the coil number 12x (n-1) + coil number 4 rises while being connected in series, and the other wiring and the U'phase power cable 3
Merge with 0 '.

In addition, wirings 22 and 2 between other coil lead wires
The wiring patterns 3, 24, and 25 are similar to those described above, and the only difference is that they are connected to the coil lead wire 41 or 42.

Here, the wirings 20 and 21 between the coil lead wires are provided.
Are parallel circuits from the same power cable 30 and have substantially the same potential at the same position, so the line voltage difference is small, and they can be installed close to each other or stacked with simple insulation. .

Next, a wiring mode of the inner stator 5 will be described with reference to FIG. Although FIG. 2 also shows only the U phase, the wiring mode is the same for the V and W phases only with different coil numbers to be connected. The phases are connected by delta connection, and the coils of the outer stator 4 and the coils of the inner stator 5 form a parallel delta connection circuit.

As shown in FIG. 3, the U-phase power cable 60 is drawn from the upper part of the pump into the casing, descends to the lower part of the outer stator 4 as it is, and is used for the power cable formed in the lower support plate 61 shown in FIG. It is introduced into the lower portion of the inner stator 5 through the through hole 62. This power cable 60
Is branched into six parallel inter-coil lead wires 50, 51, 52, 53, 54, 55 below the inner stator 5.

The wiring 50 between the coil lead wires is the coil number 136, 126, 12 × (n-
1) +4, ..., 16th, 4th coil lead wires are connected in series and then rise, and then 2nd coil lead wire 70
, No. 14, No. 26, ..., 12 × (n
−1) +2, ..., 122, 134 and the other coil lead wire 51 ′, 52 descending along the stator 5
′, 53 ′, 54 ′, 55 ′ are connected to the U′-phase power cable 60 ′ at the lower part of the inner stator 5, and again drawn out to the lower part of the outer stator 4 through the through hole 62 of the lower support plate 61 different from the above, As it is, it rises along the outer stator 4 and is drawn out from the upper part of the pump.

In addition, wiring 52, 5 between other coil lead wires
The wiring patterns 3, 54, 55 are similar to the above-described wiring mode, and the only difference is that they are connected to the coil lead wire 71 or 72.

Here, wirings 50 and 51 between the coil lead wires are provided.
Are parallel circuits from the same power cable 60 and have substantially the same potential at the same position, so the line voltage difference is small, and they can be installed close to each other or stacked with simple insulation. .

As described above, according to the present embodiment, since the wire between the coil lead wires is wired as described above, it is not necessary to wire a thick power cable in the inner stator 5 portion having a particularly narrow space where the wire can be routed. The number of power cables to be wired to the outer stator 4 portion having a relatively large space is only six.

Further, for example, wiring 20 between coil lead wires
And 21, 20 'and 21', 50 and 51, 50 'and 51'
As described above, since the potential difference of the wiring between the coil lead-out wires, which are wired close to each other in position, is small, they can be installed close to each other or stacked on each other simply by performing simple insulation. As a result, the amount of inter-line insulating material is reduced, the degree of freedom in the inter-coil wiring is increased, and the wiring space can be miniaturized.

As shown in FIG. 1 and FIG. 2, by connecting the coils which are evenly distributed, the imbalance of the impedance of the parallel circuit is eliminated, thereby suppressing the unbalanced current and improving the reliability. You can

FIG. 5 shows another embodiment of the electromagnetic pump according to the present invention. The same parts as those of the above embodiment are designated by the same reference numerals and will be described. This embodiment is a center return type electromagnetic pump similar to the above-mentioned embodiment, and a pipe 80 having a plurality of bellows between the outer stator 4 and the inner stator 5 is provided.
Is installed, and the power cable is passed through this pipe 80 so that the power cable of the inner stator 5 is
I try to pull in from the top. In this case, the wiring between the coil lead wires of the inner stator 5 is the same as that of the outer stator 4 shown in FIG.

As described above, according to this embodiment, the six power cables (two for each phase) of the inner stator 5 are connected to the outer stator 4.
It is not necessary to draw the space around, and the space required for wiring the outer stator 4 can be further narrowed.

In the above embodiment, the material used for the conductor of the coil lead wire is pure copper,
Solid solution type copper alloy (Ag-Cu, Sn-Cu), precipitated particle dispersion type copper alloy (Cr-Cu, Zr-Cu, Cr-Zr-C)
u, Be-Co-Cu), precipitation-solid solution copper alloy (Ni-
Ti-Cu, Fe-Sn- Cu), particle dispersion strengthened copper alloy _{(Al 2 o 3 -Cu, Zro} 2 -Cu, Tho 2 -C
u), fiber-reinforced copper alloys (Nb-Cu, W-Cu) and the like.

Materials applicable to the above-mentioned wiring between the coil lead wires and the insulating material of the power cable include glass, alumina, silicon carbide ceramics, silicon nitride ceramics, boron carbonitride ceramics, and aluminum nitride ceramics. , Mica ceramic, machinable ceramic, soft peeling mica, hard peeling mica, soft laminated mica,
Examples include hard mica, alumina paper, and ceramic sheets.

[0045]

As described above, according to the electromagnetic pump of the present invention, the wiring between the lead wires of a plurality of coils of the same phase forming the stator coils of the outer duct and the inner duct is connected to the power source of the same phase as the coils. Since the cable is branched into multiple parallel circuits and connected in series with a thinner conductive wire than the above power cable, the number and length of power cables to be wired inside can be reduced, and the wiring between the lead wires of the coil can be reduced. Combined with the expansion of installation freedom,
The internal wiring space can be narrowed. as a result,
It is possible to provide a compact electromagnetic pump.

[Brief description of drawings]

1A and 1B show an embodiment of an electromagnetic pump according to the present invention, and FIG. 1A is a coil wiring diagram of an outer stator,
FIG. 6B is a diagram showing a coil lead wire of the outer stator.

FIG. 2A is a coil wiring diagram of an inner stator, and FIG.
FIG. 4 is a view showing a coil lead wire of an inner stator.

FIG. 3 is an enlarged view of the electromagnetic pump in the embodiment of FIG.

4A is a plan view showing a lower support plate of the electromagnetic pump in the embodiment of FIG. 1, and FIG. 4B is a sectional view taken along line AA of FIG.

FIG. 5 is an enlarged view of a main part showing another embodiment of the electromagnetic pump according to the present invention.

FIG. 6 is an enlarged view of a main part showing a conventional electromagnetic pump.

7A is a cross-sectional view taken along the line BB of FIG.
(B) is a partially enlarged view of the outer stator and the inner stator.

FIG. 8A is a plan view showing a stator coil, and FIG.
6A is a side view of the stator coil in FIG. 7A, and FIG. 9C is an enlarged view of portion C in FIG.

FIG. 9 is a coil wiring diagram of a small capacity electromagnetic pump.

[Explanation of symbols]

1 Outer Duct 2 Inner Duct 3 Annulus Flow Path 4 Outer Stator 5 Inner Stator 20, 21, 22, 23, 24, 25 Coil Lead-Out Line Wiring 30 Power Cable

Claims (1)

[Claims] 1. A three-phase induction type electromagnetic pump in which a flow path for flowing a conductive fluid is formed between an outer duct and an inner duct, wherein a plurality of in-phase coils constituting each stator coil of the outer duct and the inner duct are formed. An electromagnetic pump characterized in that wiring between lead wires of a coil is branched from a power cable of the same phase as the coil into a plurality of parallel circuits, and is connected in series by a conductive wire thinner than the power cable.