JP2017097965A - Internal cooled cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide internal cooled cable superior in productivity and suitable for applications that heavy-current is required.SOLUTION: Internal cooled cable comprises: a first cable part having a cable core including power line that electric current flows through and a first passage for refrigerant (return passage for refrigerant) that refrigerant cooling the cable core circulates; and a second cable part having a second passage for refrigerant (outward passage for refrigerant) communicating with the first passage for refrigerant and arranged next to the first cable part along the longer direction. The first cable part and the second cable part are formed by extrusion molding integrally.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an internal cooling cable capable of cooling the inside of a cable by circulating a refrigerant, and more particularly to a technique suitable for a rapid charging cable for an electric vehicle.

  In recent years, with the spread of electric vehicles (EV), rapid chargers have been developed extensively. The quick charger is a facility that includes a power supply unit that converts AC power into DC power, and a charging cable that connects the power supply unit and the electric vehicle, and directly charges a battery mounted on the electric vehicle. Currently, a 50 kW type (125 A) quick charger has been put into practical use, but in order to further shorten the charging time, a charging cable that can withstand a large current, that is, a charging cable with a large allowable current value has been developed. ing.

  In the cable conductor of the charging cable, heat is generated during energization due to the electrical resistance of the cable conductor, and this heat becomes a factor that degrades the cable. Therefore, the allowable current value is determined so that excessive heat generation does not occur, and the current value that can be passed is limited. Usually, in order to suppress heat generation in the cable conductor, the conductor size is increased to reduce the electrical resistance. However, when the conductor size is increased, the weight is naturally increased, which is not preferable in applications where handling is important, such as a charging cable.

  Thus, an internal cooling cable has been proposed that includes a refrigerant forward path through which a low-temperature refrigerant circulates and a refrigerant return path through which a high-temperature refrigerant heated by the heat generated by the cable conductor circulates and cools the cable conductor by circulating the refrigerant. (For example, patent document 1). In the internal cooling cable disclosed in Patent Document 1, the refrigerant forward path (outward path passage 6) is disposed inside the cable, and the refrigerant return path (return path path 10) is spirally or longitudinally disposed on the outer peripheral surface of the cable. Are arranged along. Thus, the cooling efficiency of the cable conductor can be improved by arranging the refrigerant forward path and the refrigerant return path separately.

JP 2000-133058 A

  However, in the charging cable disclosed in Patent Document 1, the first cable part including the refrigerant forward path and the second cable part including the refrigerant return path are independently manufactured and then connected. The Specifically, the second cable part is spirally wound around the outer peripheral surface of the first cable part or the clamp member is attached in a state where the second cable part is parallel to the first cable part. The That is, since a step of connecting the first cable portion and the second cable portion is required, it cannot be said that productivity is good.

  An object of the present invention is to provide an internal cooling cable that is excellent in productivity and suitable for applications requiring a large current.

An internal cooling cable according to an aspect of the present invention includes a first cable portion including a cable core including a power line through which a current flows, and a first refrigerant passage through which a refrigerant that cools the cable core flows.
A second cable portion that has a second refrigerant passage communicating with the first refrigerant passage and is arranged in parallel with the first cable portion along the longitudinal direction;
The first cable portion and the second cable portion are integrally formed by extrusion molding.

  In the internal cooling cable according to the present invention, since the first cable portion and the second cable portion are integrally formed by extrusion molding, it is excellent in productivity and suitable for applications such as quick charging that requires a large current. It is.

It is a figure which shows the quick charger which applied the cable for charging which concerns on one embodiment of this invention. It is a figure which shows the structure of the cable for charging. It is a figure which shows the nipple used for extrusion molding of the cable for charge.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram showing a quick charger C to which a charging cable according to an embodiment of the present invention is applied. As shown in FIG. 1, the quick charger C includes a charging cable 1, a power supply unit 2, and a circulation device 3, and charges a battery mounted on an electric vehicle.

  The charging cable 1 connects the power supply unit 2 and the electric vehicle EV. Specifically, one end of the charging cable 1 is connected to the power supply unit 2 and the circulation device 3, and the other end is connected to a charging facility of the electric vehicle EV via a charging coupler (not shown). The The internal cooling cable of the present invention is applied to the charging cable 1.

  The power supply unit 2 converts an AC voltage from, for example, a three-phase 200V power source into a DC voltage and supplies power. The circulation device 3 includes, for example, a cooling device (including a refrigerant tank), a pump, and the like, and circulates the refrigerant in the refrigerant return path F1 and the refrigerant forward path F2 (see FIG. 2) of the charging cable 1. For example, propylene glycol or water is suitable as the refrigerant.

  FIG. 2 is a diagram illustrating the structure of the charging cable 1. As shown in FIG. 2, the charging cable 1 includes a first cable portion 10 having a large diameter and a second cable portion 20 having a small diameter. The charging cable 1 has a “8” -shaped cross-sectional shape (so-called dharma type). The first cable portion 10 and the second cable portion 20 are arranged side by side along the longitudinal direction, and are continuously provided via the neck portion 30. That is, the first cable portion 10, the neck portion 30, and the second cable portion 20 are connected in series. The neck portion 30 may be omitted, and the first cable portion 10 and the second cable portion 20 may be directly connected.

  The first cable portion 10 has a first refrigerant passage F1 through which a low-temperature refrigerant flows, and the second cable portion 20 has a second refrigerant passage F2 that communicates with the first refrigerant passage F2. Have Here, the second refrigerant passage F2 is a refrigerant forward path for transferring the low-temperature refrigerant sent from the circulation device 3 to the first refrigerant path F1 (hereinafter referred to as “refrigerant forward path F2”). The first refrigerant passage F1 is a refrigerant return path in which the low-temperature refrigerant returns to the circulation device 3 while cooling the cable core (hereinafter referred to as “refrigerant return path F1”). The high-temperature refrigerant warmed by the heat generated by the cable core when flowing through the cooling return path F1 returns to the cooling device 3 as it is, so that the refrigerant forward path is arranged in the first cable portion 10 and the second cable portion 20 Compared with the case where the return path for the refrigerant is arranged, the cooling efficiency can be increased.

  The first cable unit 10 includes a power line 11, a control line 12, a ground line 13, a sheath 14, and a return pipe 15. A collective line formed by twisting the power line 11, the control line 12, and the ground line 13 becomes a cable core.

  Each of the power lines 11 has a configuration in which, for example, a tin-plated annealed copper wire obtained by twisting a plurality of conductor strands is further twisted into a cable conductor and covered with an insulator (for example, cross-linked polyethylene). Transmit power to charge. In the present embodiment, two power lines 11 are twisted and unitized. The configuration of the power line 11 (for example, the conductor cross-sectional area and the number of twists) is appropriately determined according to the current carrying capacity, frequency, and the like.

  Each control line 12 has a configuration in which, for example, a tin-plated annealed copper wire obtained by twisting a plurality of conductor strands is covered with an insulator (for example, cross-linked polyethylene), and a charging control device (not shown) for an electric vehicle EV. And send and receive control signals. In the present embodiment, six control lines 12 are twisted together to form a unit.

  The ground wire 13 has a configuration in which a tin-plated annealed copper wire obtained by twisting conductor wires is covered with an insulator (for example, crosslinked polyethylene).

  The return pipe 15 is made of, for example, a resin material having excellent flexibility, and is particularly preferably polyvinyl chloride having excellent refrigerant resistance and high pressure resistance. The inside of the return pipe 15 is a refrigerant return path F1 through which a low-temperature refrigerant cooled by the circulation device 3 flows. One end of the return pipe 15 is connected to a cooling device (not shown) of the circulation device 3, and the other end communicates with the forward pipe 21 (not shown) in the charging coupler, for example. By using the return pipe 15, the refrigerant return path F <b> 1 can be easily formed.

  A cable core in which the power line 11, the control line 12 and the ground line 13 are twisted is disposed inside the return pipe 15, and a refrigerant (for example, propylene glycol) circulates around these. A sheath 14 made of an insulating material (for example, cross-linked polyethylene, rubber, polyvinyl chloride, etc.) having excellent flexibility is formed on the outer peripheral surface of the return pipe 15. With this structure, for example, the contact area between the refrigerant and the cable core is increased as compared with the case where one water channel as described in Patent Document 1 is provided at the center of the cable, so that the cable core can be efficiently cooled. Can do. Since the power line 11, the control line 12, and the ground line 13 are immersed in the pressure-fed refrigerant, it is preferable to have a high withstand voltage that has excellent refrigerant resistance.

  The second cable portion 20 has a configuration in which a sheath 22 made of, for example, cross-linked polyethylene is formed on the outer peripheral surface of the forward path pipe 21. The forward pipe 21 is made of, for example, polyvinyl chloride, similarly to the backward pipe 15. The inside of the outgoing pipe 21 is a refrigerant outgoing path F2 that transfers the low-temperature refrigerant cooled by the cooling device to the refrigerant return path F1. One end of the outgoing pipe 21 is connected to a pump (not shown) of the circulation device 3, and the other end communicates with the return pipe 15 (not shown) in, for example, a charging coupler. By using the outgoing pipe 21, the refrigerant outgoing path F2 can be easily formed.

  The low-temperature refrigerant cooled by the cooling device 3 flows through the refrigerant forward path F2 and is transferred to the refrigerant return path F1. The heat generated in the cable conductor when energized is absorbed by the low-temperature refrigerant flowing through the refrigerant return path F1. The warmed high-temperature refrigerant flows through the refrigerant return path F1, returns to the cooling device 3, and is cooled. Thus, the refrigerant circulates in the refrigerant forward path F2 and the refrigerant return path F1.

  Since the refrigerant flows through the refrigerant return path F1, heat generation of the cable conductor is suppressed, so that the allowable current value increases even if the conductor size is the same. Therefore, it is possible to increase the current while maintaining the current cable size. For example, in a charging cable without a refrigerant flow path, if it is attempted to increase the energization current, it is necessary to increase the conductor size of the power line, and the approximate weight increases accordingly, but in the charging cable 1 of the present embodiment, This can be handled while maintaining the conductor size.

  In the charging cable 1, the refrigerant return path F1 and the refrigerant outbound path F2 are formed separately, so that the influence of mutual heat can be almost ignored. Therefore, the cooling efficiency of the cable conductor is improved as compared with the case where the refrigerant return path F1 and the refrigerant outbound path F2 are arranged close to each other.

  The sheath 14 of the first cable portion 10 and the sheath 22 of the second cable portion 20 are integrally formed by extrusion molding. A method similar to that of a general self-supporting cable can be applied to the extrusion molding of the sheaths 14 and 22. For example, using the nipple 40 shown in FIG. 3, the forward pipe 21 is inserted into the small diameter part 41, and the return pipe 15 including the power line 11, the control line 12 and the ground line 13 is inserted into the large diameter part 42. In this state, the first cable portion 10 and the second cable portion 20 can be easily integrated by extruding the sheaths 15 and 22. Since the first cable portion 10 and the second cable portion 20 are integrated in the charging cable 1, the charging cable 1 is excellent in handling and can be easily handled by a general user who performs a charging operation.

  As described above, the charging cable 1 (internal cooling cable) according to the embodiment includes the cable core including the power line 11 through which the current flows, and the refrigerant return path F1 (first refrigerant) through which the refrigerant that cools the cable core flows. And a refrigerant forward path F2 (second refrigerant path) communicating with the refrigerant return path F1, and in parallel with the first cable section 10 along the longitudinal direction. And a second cable portion 20 provided. The first cable portion 10 and the second cable portion 20 are integrally formed by extrusion molding. In other words, the first cable portion 10 and the second cable portion 20 are connected to each other via the neck portion 30 or without the neck portion 30.

  In the charging cable 1, the first cable portion 10 and the second cable portion 20 are integrally formed by extrusion molding, so that the productivity is excellent and the handling property is good. Further, since the refrigerant return path F1 and the refrigerant outbound path F2 are formed apart from each other, the cooling efficiency of the cable core is high. Therefore, it is suitable as a charging cable that requires a large current.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the above embodiment, and can be changed without departing from the gist thereof.

  For example, one or more return pipes dedicated to the refrigerant return path F <b> 1 in which no cable core is arranged may be arranged in the first cable portion 10. In this case, the return pipe is arranged close to the power line. When multiple pipes dedicated to the return path for the refrigerant that do not have a cable core inside are arranged, the contact area between the return path for the refrigerant and the power line increases, so the cable core can be more efficiently used than in the case of a single pipe. Can be cooled.

  Further, for example, the refrigerant return path F1 and the refrigerant outbound path F2 can be formed by extrusion molding. In this case, the return pipe 15 and the forward pipe 21 can be omitted.

  Further, for example, the refrigerant forward path is arranged in the first cable portion 10 and the refrigerant return path is arranged in the second cable portion 20 so that the low-temperature refrigerant flowing through the refrigerant outward path absorbs the heat generated by the cable core and warms it up. The generated refrigerant may flow through the refrigerant return path and return to the cooling device. Although the warmed refrigerant flows through the second cable portion 20, the cooling return efficiency of the cable core is ensured because the return path for refrigerant and the forward path for refrigerant are formed apart from each other.

  The internal cooling cable of the present invention is not limited to a charging cable, and is suitable for applications that require a large current.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 Charging cable (internal cooling cable)
2 Power supply unit 3 Circulator 10 First cable part 11 Power line 12 Control line 13 Ground line 14 Sheath 15 Return pipe 20 Second cable part 21 Outward pipe 22 Sheath C Quick charger F1 Return path for refrigerant (first Refrigerant passage)
F2 Refrigerant outbound path (second refrigerant path)

Claims (6)

A first cable portion having a cable core including a power line through which a current flows, and a first refrigerant passage through which a refrigerant for cooling the cable core flows;
A second cable portion that has a second refrigerant passage communicating with the first refrigerant passage and is arranged in parallel with the first cable portion along the longitudinal direction;
The internal cooling cable, wherein the first cable portion and the second cable portion are integrally formed by extrusion molding.   The internal cooling cable according to claim 1, wherein the first refrigerant passage and the second refrigerant passage are formed of pipes.   The internal cooling cable according to claim 1, wherein the cable core is disposed in the first refrigerant passage.   The internal cooling cable according to claim 2, wherein the pipe forming the first refrigerant passage is disposed in the first cable portion in proximity to the power line.   5. The internal cooling cable according to claim 4, wherein a plurality of the pipes forming the first refrigerant passage are arranged in the first cable portion in proximity to the power line. The second refrigerant passage is a refrigerant outgoing path through which a low-temperature refrigerant sent from the circulation device flows.
The internal cooling cable according to any one of claims 1 to 5, wherein the first refrigerant passage is a refrigerant return passage through which the refrigerant flowing through the second refrigerant passage circulates and returns. .

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