JPS60257731A - Coil for electric machine - Google Patents

Abstract

PURPOSE:To prevent the damage of a conductor or an insulating connecting tube by composing to pass coolant in parallel in the holes of the conductors, and reducing pressure loss of the coolant in the coil section, thereby reducing the pressure of the coolant. CONSTITUTION:Strands 1a, 1b formed with coating insulators 13 are aligned laterally at the outside of conductors 12 formed with holes 11 for longitudinally passing coolant to be wound in a coil shape. The ends of the strands 1a, 1b are exfoliated at the insulators 13 to expose the conductors 12, hollow bases 20a, 20b are respectively welded to the ends of the strands 1a-1, 1b-12, terminals 21a, 21b are respectively mounted at the bases 20a, 20b, and connected with insulating connecting hollow tubes 22a, 22b. Coolant is supplied through the tubes 22a, 22b to the strands 1a, 1b and exhausted from the tube 22c. Thus, the pressure loss of the coolant decreases in the coil section to circulate the coolant by a low pressure pump, thereby reducing the possibility of damage of the conductors and the connecting tubes.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an electric machine coil, and particularly to a structure suitable for direct cooling.

[Technical background of the invention and its problems]

Electrical coils that generate a high magnetic field by passing a large current are directly cooled by a method in which a refrigerant is passed longitudinally along the conductor. Conventionally, such electrical coils are made by winding an insulated wire around a conductor with holes for the flow of refrigerant, attaching terminals to hollow caps welded to both ends of the conductor, passing current through, and connecting an insulated connecting tube to the cap. The heat generated by the conductor was removed by flowing a fluid or gaseous refrigerant through it.

However, since the refrigerant flows along the conductor, if the pressure loss in the insulated connecting pipe is small, the pressure loss in the electric machine coil is proportional to the cube of the total length of the conductor. Therefore, as electric coils become larger, the overall length of the conductor becomes longer, resulting in a rapid increase in pressure loss, and the pump that circulates the refrigerant becomes high pressure and uneconomical. There was a risk of damage to the pipes, etc., and there were drawbacks such as low reliability.

[Purpose of the invention]

An object of the present invention is to provide an electric coil that has a structure that reduces the pressure loss of the refrigerant flowing through the holes of the conductor, thereby lowering the pressure of the refrigerant and eliminating damage to the conductor, insulated connecting pipe, etc., and increasing reliability. With the goal.

[Summary of the invention]

In order to achieve the above object, in the present invention, a plurality of strands of wire, each of which is coated and insulated on the outside of a conductor having holes through which a refrigerant passes in the longitudinal direction, are arranged in parallel and wound into a coil. The ends of the conductors are connected in series by welding hollow caps,
An electric machine coil is provided, characterized in that the refrigerant is passed from the base to the holes of each conductor in parallel.

[Embodiments of the invention]

An embodiment of the present invention shown in the drawings will be described below. In Figures 1 and 2, (1) is a strand of conductor (12) with a hole (Jl) through which refrigerant passes in the longitudinal direction, and a conductor (12) coated with insulation (13) on the outside, which has the same shape. Element wire (1a
) and (1b) are arranged side by side, and (Ia-
12) , (]Ib-12-(la-7) , (]
Wind it into a coil like Ib-7, fold it back at the right end, and
In the second U layer of the layer (]a-6), (lb-6) -
It is wound like (la-1) and (Ib-1).

Each end of the strands (Ia) and (lb) is coated with insulation (]3
) is peeled off to expose the conductor (12), and the strands (Ia-],
) A hollow cap (20a) is welded to the end of the cap (20a).
A terminal (21a) is attached to a), and an insulated connecting tube (22a) communicating with the hollow space is connected to the terminal (21a). Element wire (Ib-12)
A hollow cap (20b) is welded to the end of the cap (20b).
A terminal (21b) is attached to b), and an insulated connecting pipe (22b) communicating with the hollow space is connected to the terminal (21b). Element wire (], Ib-1
There is a hollow cap (30) between the ends of and (], a-1, 2).
are welded and connected with an insulated connecting pipe (22c) that communicates with the hollow space.

Figure 3 is an equivalent circuit of an electric machine coil. Insulated connection tube (2
2a) and (22b) are connected to the header (40) and the refrigerant supplied from the refrigerant inlet (40a) is connected to the coil portion (50).
The insulating connecting tube (22c) is connected to the header (41) and the refrigerant outlet (4
Discharge the refrigerant from 1a).

Next, the effect will be explained. The current flows from the terminal (21a) to the wire (I
a-])-+(Ia-2)-(la-12) → Base (3
0) → Element wire (lb-1) → (], Ib-2-(], Ib
-1, 2 → terminal (21, b).

The refrigerant flows in parallel through two passages: → insulated connecting pipe (22c) → header (4]). If the heating value of the coil is the same as before, the flow rate of the refrigerant is ``. A conventional flow rate of 172 per passage is sufficient.

The pressure loss within the refrigerant coil is reduced by the insulated connection pipe (22a).
.

When the pressure loss is small, such as (22b) and (22c), it is proportional to the cube of the length of the refrigerant passage, so the pressure loss of each passage is 1/8 compared to the conventional one.

Therefore, since the pressure loss in the refrigerant passage is 1/8, the discharge pressure of the refrigerant circulation pump used is 1/8 compared to the conventional one.
Moreover, the maximum pressure generated in the strand (1) is lower than that of the conventional 1
78, so conductor (12), insulated connection pipe (22a),
The pressure resistance of (22b) and (22c) may be reduced to 1/8.

Therefore, the pump is compact and economical, and there is less possibility of damage to the conductor or insulated connecting pipe, improving reliability.

FIG. 4 shows another embodiment, in which the left end of the U-layer wire (1a) is connected to the base (20a), and the right ends of the UL wire (la) and the L-layer wire (1a) are connected to the base (20a). 30), the L layer strand (1a
) and the left end of the U-layer wire (1b) to the cap (30), and the left end of the U-layer wire (1b) and the L-layer wire (]Ib to the cap (30).
0), the right end of the L-layer wire (1b) is welded to the cap (20b), and the current is passed in series and the refrigerant is passed in parallel to the four passages.

With such a structure, the pressure loss in the refrigerant passage becomes even smaller.

Note that in the above, the arrangement of the conductors (], Ia, and (lb) was the same for both the U layer and the L layer, but the arrangement of either layer may be reversed. Although the number of layers may be one or more layers, the connections between conductors do not necessarily have to be in adjacent layers.

FIGS. 5 and 6 show other embodiments 1, strands (]
), as shown in Figure 5, a plurality of conductors (2) made of copper, superconductors, or a combination thereof are inserted into the tube (3) with a gap (4) for passage of refrigerant. coated insulation on the outside of (
5), the wire (1) is lined up and wound into a coil shape, and the end of the wire (1a) is connected to the cap (20) as shown in Figure 6.
a), the end of the wire (] Ib is placed in the base (20b), and the ends of each of the strands (la) and (Ib) are placed in the base (30), respectively.
) are welded to form the coil portion (50). The refrigerant is supplied to the header (40) from the refrigerant inlet (40a),
Insulated connection tubes (20a), (20b), (20c)
The refrigerant passes through the caps (20a), (30), and (20b) in parallel to each strand, and passes through the 1" gold (30), the insulating connection pipe (30), the header (41), and the refrigerant outlet (41a).
). The electrical connection is made from the terminal (2]a) through the header (40), through the header (40) in which each of the wires (la) and (Ib) are connected in series, and to the terminal (21b). The whole is housed in a container (60) and cooled by supplying another refrigerant from the refrigerant inlet/outlet (60a), and if necessary, evacuated. By adopting such a 4II structure, the pressure loss of the refrigerant is reduced, and at low pressure,
Since it can be circulated and the withstand pressure of the tube (3) is much lower, there is less possibility of damage to the wires, insulated connecting tubes, etc., and reliability is improved.

As described above, according to the present invention, a plurality of strands of strands insulated on the outside of a conductor having holes through which a refrigerant passes in the longitudinal direction are arranged in parallel and wound into a coil shape, and the cable wire is wound around the end of the conductor. Hollow 10-karat gold pieces are welded and connected in series, and the refrigerant is passed in parallel from the cap to the holes of each conductor, so the pressure loss of the refrigerant in the coil part is low and the refrigerant is circulated by a low-pressure pump. It is economical because it can be In addition, the pressure of the refrigerant inside the conductor is low, which may cause damage to the conductor or insulated connecting pipe.
This has the beneficial effect of reducing performance and improving trust.

[Brief explanation of drawings]

Fig. 1 is a front view showing an embodiment of the electric coil of the present invention, Fig. 2 is a longitudinal cross-sectional view taken along line A-A in Fig. 1, and Fig. 3 is a cooling equivalent of the electric coil in Fig. 1. Circuit diagram, Fig. 4 is an equivalent circuit diagram for cooling an electric machine coil showing another embodiment, Fig. 5 is a vertical cross-sectional view of a wire showing another embodiment, and Fig. 6 uses the wire shown in Fig. 5. FIG. 3 is a cooling equivalent circuit diagram of an electric machine coil. 1 Element wire 20, [cap 21, terminal 22, insulated connecting tube 40, header 4], header 50, coil section 60, container agent, patent attorney, 2-male figure 3

Claims (2)

[Claims] (1) A plurality of wires having passages for passing refrigerant in the longitudinal direction are arranged in parallel and wound into a coil, the ends of each of the wires are connected in series, and the refrigerant is passed from each end in parallel to the passage. An electrical coil characterized by being configured to pass through the coil. (2) The strands are insulated on the outside of the conductor having holes in the longitudinal direction, and each strand is connected in series by welding a hollow cap to the end of the conductor, and each conductor is connected from the cap to the end of the conductor. An electric machine coil according to claim 1, characterized in that a refrigerant is passed through the holes in parallel. (:3) For the strands, multiple conductors are inserted into the tube with gaps between them, and the outside of the tube is coated and insulated, and each strand is welded to the end of the tube to conduct the conductive material. 2. The electric machine coil according to claim 1, wherein the coils are connected in series, and the refrigerant is passed from the cap to the gap in each tube in parallel.