JPH09147692A - Method for controlling arc generating part inside a switch, and the switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrict the arc energy to be generated by an internal short-circuit accident of a switch at the minimum, to prevent the breakdown of each part, and to miniaturize a device so as to reduce the weight thereof by providing electrodes, of which tips are opposite to each other, in each load side charging part conductor with three phase. SOLUTION: Electrodes 4, 5, 4, of which tips 41, 51, 41 are directed to an adjacent load side charging part conductor, are provided in a load side charging part conductor 3 so as to generate the arc 9 between the electrodes. Consequently, arc generating position is limited at two positions, and while length of the arc 9 is shortened so as to restrict the arc energy at the time of internal short- circuit accident at the minimum. Generation of damage of an internal mechanism and a case can be prevented without increasing the mechanical strength of a case or the insulating strength between each phase. Since it is unnecessary to prolong the insulated distance between each phase and provided an arc horn, outer dimension L1 of the case 1 can be set small.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling an arc generating part in a switch and a switch, and more particularly to minimizing arc energy generated in the event of an internal short circuit of the switch. The present invention relates to a switch which prevents damage to the internal mechanism of the switch and the case and can provide a small and lightweight switch.

[0002]

2. Description of the Related Art In a power distribution system, when an internal short circuit accident occurs in a switch, a circuit breaker in a substation temporarily shuts down and power is retransmitted after a predetermined time. FIG. 2 shows the structure of a conventional general switch and the state of arc generation. In the figure, 1
Is a switch case, 2 is a power source side charging portion conductor, 3 is a load side charging portion conductor, 6 is a load side bushing, 6a is a power source side bushing, 7 is an insulating plate, 8 is a contact, and 9 is an arc.

In the switch shown in FIG. 2, the plate thickness of the switch case 1 is increased in order to reduce damage to the internal mechanism and the switch case 1 due to the occurrence of the arc 9 at the time of the internal short circuit accident as described above. For example, measures are taken to increase the mechanical strength such as, for example, to lengthen the insulation distance between the phases, and to provide the insulating plates 7 and 7 between the phases. Therefore it had been forced to equal size by increasing the outside dimension L ₂ of the weight gain and switch case 1 of the switch.

Even when the above measures are taken, the arc 9 between the phases extends toward the load side bushing 6 as the current becomes larger, so that the load side bushing 6 is inevitably damaged. Further, since the load side bushing 6 and the contactor 8 are damaged by the thermal energy of the arc that has been elongated for a long time, there is a problem that an internal short circuit accident further occurs and secondary damage occurs when the power is retransmitted. .

[0005]

To solve these problems, it has been proposed to prevent the internal mechanism and the case from being damaged in the event of an internal short-circuit accident by mounting an arc horn on the case between the phases inside the switch. ing.

FIG. 3 is a schematic explanatory view showing the structure of a switch equipped with an arc horn and the state of arc generation. When an internal short circuit occurs when the switch is closed, the arc horn 10 is provided between the load side bushings 6 as shown in the figure, so that the contacts 8 of each phase and the load side charge are integrated. An arc 9 is formed between the partial conductor 3 and the arc horn 10.
Occurs, and the arc 9 does not extend toward the bushing 6. Therefore, the bushing 6 is protected.

However, when the thermal energy of the arc 9 causes the contactor 8 and the load-side charging part conductor 3 to be worn out and melts, the distance between the contactor 8 and the load-side charging part conductor 3 and the arc horn 10 is increased. When the power is re-transmitted from the substation, an internal short-circuit accident further occurs, the arc length becomes longer, and the arc energy also increases. Further, since the arc is generated at the contact 8 of each phase, the load side charging portion conductor 3 and the arc horn 4 at four positions, the thermal energy of the arc 9 is large. Such damage is unavoidable. Further, a place for installing the arc horn 10 is required, and the size of the switch case 1 is inevitably increased by increasing the outer dimension L ₃ of the switch case 1.

Therefore, an object of the present invention is to minimize the arc energy generated at the time of an internal short circuit accident in a switch, thereby preventing the internal mechanism of the switch and the case from being damaged, and generating an arc in the switch. It is to provide a method of controlling a part and a switch. Another object of the present invention is to provide a compact and lightweight switch whose outer dimensions can be made smaller than those of conventional switch cases.

[0009]

Means of the present invention taken to solve the above problems and achieve the object are as follows. According to a first aspect of the present invention, there is provided a method of controlling an arc generating part in a switch, which is formed by accommodating a three-phase charging part in a switch case at a time. It is a method for controlling an arc generating part in a switch, characterized in that an electrode facing an adjacent load side charging part conductor is provided so that an arc is generated between the electrodes.

According to a second aspect of the present invention, in a switch in which a three-phase charging section is housed together in a switch case, a load-side charging section in which a tip end is adjacent to each load-side charging section conductor is provided. The switch is characterized in that an electrode facing the conductor is provided, and the tips of the electrodes are arranged to face each other.

[0011]

[Operation] The load side charging part conductor is provided with an electrode whose tip end faces the adjacent load side charging part conductor so that an arc is generated between the electrodes. Therefore, there are two arc generation points. Further, since the electrode tips are arranged so as to face each other, the length of the arc is shortened, and the arc energy at the time of an internal short-circuit accident can be minimized in combination with the number of locations where the arc is generated. Therefore, damage to the internal mechanism of the switch and the case due to arc energy can be prevented without increasing the mechanical strength of the switch case or the insulation strength between the phases.

Further, it is not necessary to increase the insulation distance between the phases, and it is not necessary to install an arc horn. Therefore, the external dimensions of the switch case can be set smaller accordingly, and a switch that is smaller and lighter than the conventional switch can be provided.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory diagram showing an internal structure of an embodiment of a switch according to the present invention and an arc generation state.
The load side charging section conductors 3, 3 and 3 have tip portions 41, 51,
Electrodes 4, 5 whose 41 is directed to the load side charging section conductors adjacent to each other.
4 are provided. Tip portions 41, 5 of the electrodes 4, 5, 4
Reference numerals 1 and 41 are formed in an arc shape, and are arranged so as to face each other. Copper and tungsten alloys are used as materials for electrodes, but other materials such as copper, brass, iron,
It is also possible to use a conductive material such as stainless steel.

The electrodes 4, 5, 4 are provided with elongated holes 40, 50, 40 parallel to the axial direction thereof for adjusting the distance. The long holes 40, 40 are provided on the base side of the electrodes 4, 4, and the long hole 50 is provided at the center of the electrode 5. Then the electrodes 4,
The screws 5 and 4 are fixed to the load side charging unit conductors 3, 3 and 3 by screws 11 that penetrate the elongated holes 40, 50 and 40. In addition, if the gap between the phase electrodes 4, 5, 4 is set in advance at an optimum distance so that the arc lengths 9, 9, 9 between the phases generated at the time of internal short circuit are shortened, the long holes 40, 50, 40
You may use a round hole instead of.

[0015]

The gap between the phase electrodes 4, 5, 4 is set at an optimum distance so that the arc lengths 9, 9, 9 between the phases generated at the time of internal short circuit are shortened. If the gap between the phase electrodes is too close, the insulation distance normally required for the switch cannot be maintained. If they are too far apart, the arc length at the time of an internal short circuit becomes long and the arc energy becomes large. Therefore, the minimum dimension is set within the range that satisfies the insulation resistance.

The load side charging section conductors 3, 3, 3 have a tip 4
Electrodes 1, 5, and 4 are provided so that the load-side charging portion conductors 1, 51 and 41 are adjacent to each other, and an arc is generated between the electrodes. Therefore, there are two arc generation points. Further, since the tip portions 41, 51, 41 of the electrodes are arranged so as to face each other, the length of the arcs 9, 9, 9 is shortened, and the arc energy at the time of an internal short-circuit accident is combined with the number of arc generation points. Can be kept to a minimum. Therefore, damage to the internal mechanism of the switch and the case due to arc energy can be prevented without increasing the mechanical strength of the switch case or the insulation strength between the phases.

Further, it is not necessary to lengthen the insulation distance between the phases, and it is not necessary to install an arc horn. Therefore, the outer dimension L ₁ of the switch case 1 can be set smaller accordingly.
That is, L ₁ <L ₂ and L ₃ can be satisfied, and the size can be reduced as compared with the conventional switch.

The present invention is not limited to the illustrated embodiment, and various modifications can be made within the scope of the claims. Further, the same or equivalent portions are denoted by the same reference numerals throughout the drawings.

[0019]

According to the present invention, the load side charging section conductor is
An electrode is provided so that its tip end faces an adjacent load-side charging portion conductor, and an arc is generated between the electrodes. Therefore, there are two arc generation points. Further, since the electrode tips are arranged so as to face each other, the length of the arc is shortened, and the arc energy at the time of an internal short-circuit accident can be minimized in combination with the number of locations where the arc is generated. Therefore, damage to the internal mechanism of the switch and the case due to arc energy can be prevented without increasing the mechanical strength of the switch case or the insulation strength between the phases.

Further, it is not necessary to increase the insulation distance between the phases, and it is not necessary to install an arc horn. Therefore, the outer dimension L ₁ of the switch case can be set smaller accordingly, and a switch that is smaller and lighter than the conventional switch can be provided.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an internal structure and an arc generation state of an embodiment of a switch according to the present invention.

FIG. 2 is a schematic explanatory view showing a structure of a conventional general switch and an arc generation state.

FIG. 3 is a schematic explanatory view showing a structure of a switch equipped with an arc horn and an arc generation state.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Switch case 2 Power supply side charging part conductor 3 Load side charging part conductor 4 Electrode 5 Electrode 6 Load side bushing 6a Power supply side bushing 7 Insulating plate 8 Contact 9 Arc 10 Arc horn L ₁ Outline of switch case according to the present invention Dimensions L ₂ External dimensions of conventional switch case L ₃ External dimensions of conventional switch case with arc horn

Claims (2)

[Claims] 1. A method for controlling an arc generating part in a switch, wherein a three-phase charging part is housed together in a switch case, wherein each load side charging part conductor has a tip end adjacent to a load side. A method for controlling an arc generation part in a switch, characterized in that an electrode facing a charging part conductor is provided so that an arc is generated between the electrodes. 2. A switch in which a three-phase charging section is housed together in a switch case, wherein each load side charging section conductor (3,3,3) has a tip (41,51,41). Electrodes (4,5,4) facing the load side charging section conductors adjacent to each other are provided, and the tips (41,51,41) of the electrodes (4,5,4) are arranged facing each other. Switch that is characterized by being.