JPH0564414A - Electromagnetic pump - Google Patents

Abstract

PURPOSE:To improve a heat recovery and the efficiency and reliability of an electromagnetic pump by lowering and leveling the temperature rise of each part through arranging a comb-type cooling member or cooling member equipped with a cooling fluid path between laminated core blocks so that the cooling member covers a stator coil. CONSTITUTION:Heat generated in a stator coil 9 is transmitted from an outer duct 3 via laminated core block 7 to the conductive fluid 2 in an annular passage 5, also from the circumference of the laminated core block 7 via inert gas 23 and casing 22 to the conductive fluid 2 in which an electromagnetic pump 20 is immersed, and further from the stator coil 9 directly via the side faces of a cooling member 21 and the laminated core block 7 to the cooling member 21, and transferred via the inert gas 23 and casing 22 to the conductive fluid 2. Thus, even if a gap 8 is provided, the heat transfer from the stator coil 9 directly to the laminated core block 7 and cooling member 21 and from the side face of the laminated core block 7 to the cooling member 21 is conducted effectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention applies a traveling magnetic field to a conductive fluid from outside to induce an induced current in the conductive fluid, and causes a pumping action by the interaction between the induced current and the external magnetic field. Regarding electromagnetic pumps.

[0002]

2. Description of the Related Art In an induction type electromagnetic pump, three-phase windings are arranged in the flow direction of the electromagnetic pump in the order of respective phases, and when a three-phase alternating current is applied to the three-phase winding, the three-phase windings move in the flow direction. A magnetic field is generated. When this traveling magnetic field is made to pass through the duct in which the conductive fluid is present, a voltage is induced in the conductive fluid by the Fleming's right-hand rule, which causes an induced current. This induced current and a part of the component of the traveling magnetic field act to generate an electromagnetic force, which acts as a pump because it receives a force for flowing a conductive fluid. This electromagnetic force is the same as the torque in the induction motor and the thrust in the linear motor.

These three-phase induction type electromagnetic pumps are roughly classified into two types, a flat linear type electromagnetic pump and an annular linear type electromagnetic pump, in terms of structure. The present invention relates to an improvement of the annular linear type electromagnetic pump, and in this annular linear type electromagnetic pump, the ALIP (Annular Linear Ind.
uction pump), which has been widely adopted in recent years because of its high reliability and safety of duct structure.

The basic structure is shown in the partially cutaway perspective view of FIG. In the electromagnetic pump 1, the flow path through which the conductive fluid 2 made of, for example, liquid metal sodium flows, forms an annulus flow path 5 having a concentric double pipe structure with an outer duct 3 and an inner duct 4. Further, a laminated core block 7 in which electric iron plates having slots 6 formed in order to form a magnetic circuit of an alternating magnetic field is stacked in a circumferential direction on the stator is provided with an outer duct 4
A plurality of them are arranged with a gap 8 in the circumferential direction outside.
In this case, the laminated surface faces the outer duct 4, and the slots 6 are further inward so that the laminated core block 7
The whole is radial.

A ring-shaped stator coil 9 is wound inside the slot 6, and a large number of stator coils 9 are arranged in the axial direction and connected so that a three-phase alternating current produces a traveling magnetic field. .. Further, an inner core 10 for forming a magnetic circuit is housed inside the inner duct 4. As a result, the conductive fluid 2 enters the electromagnetic pump 1 from the fluid inlet 11 and flows through the annulus flow path 5 to induce pressure, and is delivered from the fluid outlet 12. The laminated core block 7 and the stator coil 9 are cooled by a circulating gas by an external fan (not shown).

In recent years, in order to improve the design of the plant by increasing the capacity of the electromagnetic pump 1 and eliminating restrictions on the installation place, the electromagnetic pump 1 is made smaller and the installation place of the electromagnetic pump 1 is saved to reduce the entire plant. In order to contribute to downsizing, it is required to operate the electromagnetic pump 1 by immersing it in the conductive fluid 2.

To meet these demands, the stator coil 9 is not forced gas cooled as described above, but
It is necessary to cool the jacket surface without circulating a cooling gas, which has many advantages:

That is, since the space for circulating the cooling gas can be omitted, the external dimensions can be reduced. Further, since an external device such as a fan and a pipe for circulating the cooling gas is unnecessary, the entire device of the electromagnetic pump can be made compact, and the structure of the immersion type and the condition for maintenance are improved. Further, when the outer surface of the casing is cooled, the stator coil can be arranged in the inner core 10 when the machine becomes a large capacity machine to some extent, so that the output of the electromagnetic pump is further increased and the size is further reduced. It will be easy.

Further, when the outer surface of the jacket is cooled, the heat loss generated in the stator coil 9 is transmitted from the stator coil 9 to the laminated core block 7, and the laminated core block 7 serves as the outer duct 3 and a casing (not shown). To be further transferred to the conductive fluid 2. Therefore, it is necessary to make the thermal resistance from the stator coil 9 to the conductive fluid 2 as small as possible, and for that purpose it is desirable that these structures contact each other during operation.

[0010]

In order to increase the output of the electromagnetic pump 1, it is necessary to flow a large amount of current through the stator coil 9. For this purpose, it is effective to minimize the temperature rise of the stator coil 9. Further, in general, the conductive fluid 2 often has a high temperature, so that the electromagnetic pump 1 immersed in the conductive fluid 2 is operated at a high temperature.

However, the electromagnetic pump 1 is assembled at room temperature and operated at various temperatures up to 600 ° C. Therefore, at any of these temperatures, it is necessary not to receive stress due to the difference in thermal expansion between the structures and to efficiently transfer the heat generated in the stator coil 9 to the conductive fluid 2.

In order to increase the pump capacity and reduce the size of the electromagnetic pump 1 as described above, the heat generated in the stator coil 9 serving as the heat generating portion is efficiently transferred to the conductive fluid 2. The point is to reduce the temperature rise and increase the current flowing through the stator coil 9 as much as possible. However, in the conventional electromagnetic pump 1, the heat generated in the stator coil 9 is transferred into the inductive fluid 2 via the laminated core block 7 and the outer duct 3, and the stator coil 9 and the laminated core block 7 It is transmitted to the inductive fluid 2 through an inert gas filled in the surroundings and a casing (not shown).

However, it is necessary to provide a gap 8 or the like between the outer duct 3 and the laminated core block 7 in order to avoid interference due to the difference in expansion caused by thermal expansion. It has been difficult to reduce the heat transfer from the coil and efficiently transfer the heat generated in the stator coil 9 to the conductive fluid 2. Therefore, there is a tendency that the temperature of the portion of the stator coil 9 that is not sandwiched between the laminated core blocks 7 becomes high locally.

The object of the present invention is to provide a cooling member between the stator coil arranged around the outer duct and each laminated core block so that the heat generated in the stator coil can be efficiently transferred to the outside. It is also transferred to a conductive fluid to reduce and level the temperature rise of each part to improve the heat recovery rate and the efficiency and reliability of the electromagnetic pump, resulting in downsizing and large capacity. It is to provide an electromagnetic pump capable of performing.

[0015]

A plurality of laminated cores each having an outer duct and an inner duct forming a double cylinder having an annulus flow path through which a conductive fluid flows and an slot disposed on the outer circumference of the outer duct. An electromagnetic pump comprising a block and a stator coil that creates a traveling magnetic field in the annulus flow path in which the conductive fluid is wound around a slot of the laminated core block, wherein the stator coil is provided between the laminated core blocks. Comb-shaped cooling member to cover the
Alternatively, a cooling member having a cooling fluid path is provided.

[0016]

The heat generated in the stator coil is transferred to the laminated core block in the portion sandwiched between the laminated core blocks, and to the internal portion of the casing through the cooling member in the portion sandwiched between the other cooling members. Heat is released to the active gas. Further, the inert gas is also transmitted from the side surface of the laminated core block through the cooling member. The heat of the inert gas is transferred to the external conductive fluid via the casing.

Further, when the cooling fluid passage is provided in the cooling member, a part of the conductive fluid flowing in the annulus passage is returned by bypassing the cooling fluid passage due to the fluid output and the pressure difference at the inlet. To do. The heat generated in the stator coil can be transferred to the conductive fluid in the annulus passage through the cooling member, and the heat can be efficiently transferred to the conductive fluid in the annulus passage. As a result, the temperature rise of each part of the laminated core block and the stator coil is reduced and leveled.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. It should be noted that the same components as those of the above-described conventional technique are denoted by the same reference numerals and detailed description thereof will be omitted.

FIG. 1 is a vertical sectional view of the electromagnetic pump, and FIG. 2 is a sectional view taken along the line AA of FIG. Electromagnetic pump
In 20, a duct for flowing the conductive fluid 2 shown by an arrow has a concentric double pipe structure composed of an outer duct 3 and an inner duct 4 to form an annulus passage 5. Further, a plurality of laminated iron core blocks 7 in which electric iron plates having slots 6 formed in order to form a magnetic circuit of an alternating magnetic field are stacked on the stator in the circumferential direction are provided outside the outer duct 4 with a gap 8 or the like in the circumferential direction. It is arranged.
In this case, the laminated surface faces the outer duct 4, and the slots 6 are further inward so that the laminated core block 7
The whole is radial.

A ring-shaped stator coil 9 is wound in the slot 6, and a large number of the stator coils 9 are arranged in the axial direction and are connected so that a three-phase alternating current produces a traveling magnetic field. .. Further, an inner iron core 10 for forming a magnetic circuit is housed inside the inner duct 4. As a result, the conductive fluid 2 enters the electromagnetic pump 20 from the fluid inlet 11, pressure is induced while flowing through the annulus flow path 5, and the conductive fluid 2 is delivered from the fluid outlet 12.

Between the plurality of laminated iron core blocks 7, a comb-shaped fan-shaped cooling member 21 made of, for example, stainless steel, which is a non-magnetic material and has excellent thermal conductivity, is formed so as to cover the stator coil 9. Is arranged, the laminated core block 7 and the cooling member 21 are entirely covered with a casing 22 on the outer periphery of the outer duct 4, and an inert gas 23 such as nitrogen gas is filled in the inside thereof. It is operated by being immersed in the conductive fluid 2 indicated by surface 24.

Next, the operation of the above configuration will be described. The heat generated in the stator coil 9 is applied to the laminated core block 7
The electroconductive fluid 2 in which the electromagnetic pump 20 is immersed from the outer duct 3 to the electroconductive fluid 2 in the annulus flow path 5 via the above and from around the laminated core block 7 through the inert gas 23 and the casing 22. Further, it is transmitted from the stator coil 9 directly to the cooling member 21 from the side surface of the cooling member 21 and the laminated core block 7, and is transferred to the conductive fluid 2 via the inert gas 23 and the casing 22.

As a result, even if the gap 8 is provided between the outer duct 3 and the laminated core block 7 to avoid stress on each structure due to thermal expansion, the laminated core block is directly fed from the stator coil 9. 7 and the cooling member 21, and also from the side surface of the laminated core block 7 to the cooling member 21 effectively. As a result, the temperature rise of the stator coil 9 can be reduced, and the heat can be removed from the side surface of the laminated core block 7, so that the heat recovery rate is improved and the current flowing through the stator coil 9 is increased. The calorific value can be increased, the electromagnetic pump 20 can be easily downsized and the capacity can be increased, and the efficiency of the electromagnetic pump can be improved.
Further, since the temperature of each part such as the stator coil 9 and the laminated core block 7 is leveled, the dielectric strength of the stator coil 9 is improved, so that the reliability of the electromagnetic pump can be improved.

The longitudinal sectional view of FIG. 3 and the enlarged sectional view of the cooling member of FIG. 4 show another embodiment of the present invention.
4 (A) is a longitudinal sectional view of the main part, and FIG. 4 (B) is BB of FIG. 4 (A).
It is arrow sectional drawing which followed the line. The difference between the electromagnetic pump 30 and the first embodiment in structure is that a cooling fluid passage 32 is provided in the cooling member 31 for bypassing a part of the conductive fluid 2 and returning it. The channel 32 is parallel to the annulus channel 5. Further, one end of the cooling fluid passage 32 and the opening of the electromagnetic pump 30 on the fluid outlet 12 side are provided with the cooling fluid inlet pipe 33.
Thus, the other end of the cooling fluid passage 32 and the opening on the fluid inlet 11 side are communicated with each other by the cooling fluid outlet pipe 34.

In the electromagnetic pump 30 having the above-described structure, the heat generated in the stator coil 9 is conducted from the laminated core block 7 to the conductive fluid 2 via the outer duct 3 and the inert gas 23 and the casing 22. Conductivity flowing in the annulus flow path 5 due to the pressure difference between the high pressure (fluid outlet 12) and the low pressure (fluid inlet 11) generated by the operation of the electromagnetic pump 30 through the cooling member 31. A part of the fluid 2 is bypassed via the cooling fluid inlet pipe 33, the cooling fluid passage 32, and the cooling fluid outlet pipe 34, and in the cooling fluid passage 32, the stator coil 9 and the adjacent laminated core block from the cooling member 31. Recover the heat from 7.

According to the other embodiment, the structure is slightly complicated as compared with the one embodiment, but the temperature rise of the stator coil 9 and the laminated core block 7 is suppressed, the heat recovery rate and the temperature are leveled. It is possible to reduce the size and increase the capacity of the electromagnetic pump.

[0027]

As described above, according to the present invention, the apparatus of the electromagnetic pump is compact, the heat generated in the stator coil can be efficiently removed, the temperature rise of the stator coil can be suppressed, and the laminated iron core can be suppressed. By equalizing the temperature of the block and the stator coil, the heat generation of the stator coil can be set higher than before, which improves the efficiency and reliability of the electromagnetic pump and reduces the size of the large capacity. There is an effect that an electromagnetic pump can be provided.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional configuration diagram showing an embodiment of an electromagnetic pump of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a vertical cross-sectional configuration diagram showing another embodiment of the electromagnetic pump of the present invention.

FIG. 4 is an enlarged sectional view of a cooling member portion according to another embodiment of the present invention. (FIG. 4A is a vertical cross-sectional view of the main part. FIG. 4B is a cross-sectional view taken along the line BB of FIG. 4A.)

FIG. 5 is a partially cutaway perspective view of a conventional electromagnetic pump.

[Explanation of symbols]

2 ... Conductive fluid, 3 ... Outer duct, 4 ... Inner duct, 5
... annulus passage, 6 ... slot, 7 ... laminated core block, 8 ... gap, 9 ... stator coil, 10 ... inner core, 11 ...
Fluid inlet, 12 ... Fluid outlet, 20, 30 ... Electromagnetic pump, 21, 31
... cooling member, 22 ... casing, 23 ... inert gas, 24 ... liquid level, 32 ... cooling fluid passage, 33 ... cooling fluid inlet pipe, 34 ... cooling fluid outlet pipe.

Claims (1)

[Claims] 1. An outer duct and an inner duct that form a double cylinder having an annulus passage for flowing a conductive fluid in the middle portion, and a plurality of laminated core blocks having slots formed on the outer periphery of the outer duct. In an electromagnetic pump comprising a stator coil wound around a slot of a laminated core block and creating a traveling magnetic field in the annulus passage in which the conductive fluid exists, the stator coil is covered between the laminated core blocks. An electromagnetic pump in which a comb-shaped cooling member is arranged in this manner.