JPH0241855B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a holding device for a switch in a three-phase power distribution line.

Conventional switches installed in three-phase distribution lines use magnets for normal switching operations, and when a short-circuit accident occurs in the load, the switch remains closed until the fault current falls below the non-breaking current value ( To lock)
Electric power is sent to the above magnet from a current transformer (for example, Utility Model Application No. 56-26831,
(See Publication No. 89142).

Conventional configurations of this type have two cases: when power is sent from one current transformer to the magnet (two-phase short circuit);
If the power is sent from two current transformers (three-phase short circuit), the power value will vary significantly (nearly twice as much). Therefore, there are difficulties in coordinating OCR adjustment at substations, and improvements have been desired.

Therefore, in the present invention, the plunger 19 of the closing magnet 17 is connected to the switch 70 provided on the three-phase distribution line, and the coil 18 of the closing magnet 17 is connected to the switch 70 of the three-phase distribution line. is connected to the power supply side, and closes the switch 70 depending on the presence or absence of voltage of the three-phase distribution line,
A shaft 52 is configured to open and operate, and is also connected to the plunger 19 and provided to rotate in conjunction with the operation of the plunger 19.
and a holding magnet 66 which operates the plunger 68 depending on whether or not a coil 67 connected to the power supply side of the three-phase distribution line switch 70 is energized; The two provided engaging bodies 44 and the plunger 68 of the holding magnet 66 are connected to each other via interlocking rods 63, and the holding magnet 6
6 is activated, two locking bodies 43 engage with the respective engaging bodies 44 to stop the rotation of the shaft 52 and prevent the switch 70 from opening. In this device for holding a switch in a three-phase distribution line, the two interlocking rods 63 and the plunger 68 of the holding magnet 66 are connected to each other through a long hole 64 provided on one side.
and a connecting piece 6 provided on the other side and disposed within the elongated hole 64 so as to be movable in the longitudinal direction of the elongated hole.
9, and for each interlocking rod 63, two short-circuit current detection devices attached to mutually different lines on the load side of the three-phase distribution line switch 70 are connected. current transformer 72,7
3, the lock solenoids 58 each receive power from
When each lock solenoid 58 receives electric power from each current transformer 72, 73, the corresponding interlocking rod 63 is turned off by the return of the holding magnet 66.
The above-mentioned problem is solved by a structure in which the locking body 43 is attached to the locking body 43 so as to stop it from moving toward the releasing side.

The drawings showing the embodiments of the present application will be described below.
In the mechanical components (operating mechanism) mainly shown in FIGS. 1 to 4, 7 is an operating shaft;
It is rotatably attached to a base frame (not shown),
In addition, it is connected to a movable part of a switch 70, which will be described later, in a well-known manner so that it can be opened and closed.

First, in the mechanism for opening, 10 is a first lever fixed to the shaft 7, 11 is a guide plate, one end of which is connected to the free end of the first lever 10 via a pin 12. A long hole 13 is formed at the other end, and is slidably attached to a pin 14 fixed to the base frame. Reference numeral 15 denotes a release spring, which is a compression spring with a large biasing force. The positional relationship between the first lever 10 and the release spring 15 is such that in the closed state shown in FIG. Thus, the direction of the biasing force of the spring is directed toward the axial position of the operating shaft 7.

In the mechanism for next closing, reference numeral 17 denotes a closing magnet, which is constructed so that the plunger 19 is drawn into the coil 18 when the coil 18 is energized by a control circuit 75, which will be described later. 2
0 is a link connected to the plunger 19. 2
Reference numeral 1 denotes a rotating shaft, which is rotatably attached to the base frame. 22 and 23 are levers fixed to the shaft 21, respectively;
24 is a lever fixed to the operating shaft 7, and 25 is a link, one end of which is connected to the free end of the lever 24.
A long hole 26 is formed at the other end, and a pin 27 fixed to the free end of the lever 23 is inserted into the long hole 26.
6 can be freely moved in the longitudinal direction.
Reference numeral 28 indicates an operating piece fixed to the shaft 21, and 29 indicates a micro switch.

Next, in the contact extraction mechanism, 31 is the operation shaft 7
A second lever 32 fixed to is a link, one end of which is connected to the lever 31, and an elongated hole 33 formed at the other end.

Next, in the linkage mechanism between the lever 31 and the magnet 17, 34 is a shaft rotatably mounted on the base frame;
35 is a lever fixed to the shaft 34, and 36 is a link, which is connected to the free end of the lever 35 and the link 20. Reference numeral 37 indicates a lever fixed to the shaft 34, and reference numeral 38 indicates a pin fixed to the intermediate portion of the lever 37, which is movably located within the elongated hole 33. The positional relationship between the pin 38 and the elongated hole 33 is such that in the closed state shown in FIG. It is designed so that it will be done. 39 is a contact pull-out spring,
A tension spring is used, tensioned between the free end of the lever 37 and a pin 40 fixed to the base frame. Next, the holding mechanism 41 will be explained. This holding mechanism 41 has two sets of locking mechanisms 42, 42. Each locking mechanism 42 is composed of a locking body 43 and an engaging body 44. The locking body 43 includes a support piece 46 fixed to a rotatable shaft 45 and a lock roller 48 rotatably attached to the support piece 46 via a shaft 47. The locking body 43 also has a driven piece 49 formed integrally with the support piece 46. Reference numeral 50 denotes a tension spring, which is used to position the locking body 43 at the locking position. 51 indicates a spring hanging piece. The engaging body 44 is attached to a rotatable shaft 52, and a notched engaging portion 53 is formed at the tip thereof. A lever 54 is attached to the shaft 52, and this lever 54 is linked via a link 55 to a lever 56 attached to the rotating shaft 21. Next 5
8,58 indicates a rock solenoid. In these solenoids, 59 is a case, 60 is a coil, and 61 is a plunger. A biasing spring 62 is interposed between the case 59 and the locking pin 61a, and biases the plunger 61 in the direction of protruding from the coil 60. Reference numeral 63 denotes an interlocking rod, one end of which is fixed to the plunger 61, and the other end of which is provided with a long hole 64. Reference numeral 65 denotes an interlocking portion, which is formed by the wall at the lower end of the elongated hole 64. A holding magnet 66 includes a coil 67 and a plunger 68 like a well-known magnet. The magnet 66 used is one in which a coil 67 receives alternating current power to draw in a plunger 68. 69 is a linking piece fixed to the plunger 68, one end and the other end of which are connected to the linking rod 6.
It is left in the elongated hole 64 of No. 3. Next, in the circuit shown in FIG. 5, U, V, and W represent the U phase, V phase, and W phase of the three-phase high-voltage distribution line, respectively. Reference numeral 70 indicates a switch interposed in the power distribution line, and the inside thereof is provided with contacts 71, 71, 71 as is well known. Further, as is well known, the movable part of the switch that opens and closes these contacts is connected to the operating shaft 7. 7
2 and 73 are current transformers for short-circuit current detection, and a pushing current transformer is used as an example. 74
is a step-down transformer for operation power supply, and its secondary side is connected to input terminals 75a and 75b of the control circuit 75. In the control circuit 75, 76 is a relay;
7 and 78 indicate contacts in the relay 76. 79
As a rectifier, a bridge rectifier circuit configured using diodes is used as an example, but any other (half-wave, full-wave) rectifier circuit using any other rectifying elements may be used. 80 is a well-known surge absorber. The micro switch 29, relay 76, and relay contacts 77 and 78 constitute a switch S that connects and disconnects the rectifier 79 to the power supply side, that is, the transformer 74 side. Alternatively, instead of the current contacts 77 and 78, a switch connected thereto may be directly connected to the contact 71 of the switch 70 (for example, disposed at a location driven by the operating piece 28) without using a relay.

Next, FIG. 6 shows the basic structure of the relationship between the above-mentioned mechanism and the switch, and parts corresponding to those described above are given the same reference numerals and redundant explanation will be omitted.

Next, the operation of the above configuration will be explained.

(1) When switching on the switch When power is sent to the three-phase distribution line from the substation side, the transformer 74 and micro switch 29
Current flows to the relay 76 via the contacts 77, 7
8 closes. Then, the alternating current taken in through the transformer 74 is rectified by the rectifier 79 to become direct current, and the direct current is supplied to the closing magnet 17. Also, the above AC is connected to the holding magnet 66.
Also supplied. The operating mechanism then operates as follows. In other words, the state shown in Figure 1 (the same applies to Figure 6 A)
When the coil 18 of the magnet 17 is energized, the plunger 19 is drawn downward. Then lever 22, rotation shaft 21, lever 2
3. The link 25 and the lever 24 move in the direction of the arrow, respectively, and the operating shaft 7 is rotated in the direction of the arrow, that is, the closing direction. As a result, the contacts 71, 71, 71 are closed. Further, the first lever 10 moves in the direction of the arrow, and a biasing force is accumulated in the release spring 15. In this case, the link 36, levers 35, 37
etc. also move as shown by the arrows, and spring 3
A biasing force is accumulated in 9.

In addition, in the holding mechanism, the lever 56 and the link 5
5, etc., the engaging body 44 is raised in the direction of the arrow. On the other hand, when the coil 67 of the magnet 66 is energized, the plunger 68 is retracted, and the plunger 61 in the solenoid 58 is retracted against the spring force of the spring 62 via the linking piece 69 and the linking rod 63, and the locking body 43 is pulled in against the spring force of the spring 62. is brought into the state shown in FIG. 3 by the force of the tension spring 50. As a result, the engaging body 44 is connected to the locking body 43.
It is in a state where it is locked by the locking roller 48.
In addition, when the above-mentioned engaging body 44 rises, the engaging body 44
Since a sloped portion 44a is formed at the tip of the locking body 44, the locking body 43 is once rotated slightly clockwise in the figure against the force of the spring 50, the locking body 44 rises, and then it is locked. The locking roller 48 of the body 43 engages with the engaging portion 53.

Simultaneously with the above operation, the micro switch 29 is opened by the operating piece 28. As a result, the relay 76 is de-energized and the relay contacts 77 and 78 are respectively opened. As a result, the rectifier 79 is disconnected from the transformer 74, and the power supply to the closing magnet 17 is cut off. In other words, only a small holding alternating current is supplied to the coil 67 of the holding magnet 66. After the above operations are performed, the third
It becomes a closing state (holding state) as shown in the figure and FIG. 6B. In this state, since the first lever 10 and the release spring 15 are configured in the above-described relationship, the biasing force of the release spring 15 hardly acts in the direction of rotating the operating shaft 7.

(2) When a short circuit (for example, a short circuit between U and V phases) occurs on the load side of the switch 70. In this case, a large short circuit current flows, causing a voltage drop in the distribution line on the power supply side. Therefore, depending on the circuit that passes through the transformer 74, there is a possibility that the holding current will not be supplied to the coil 67 of the holding magnet 66. However, due to the above-mentioned short circuit, a large short circuit current flows through the U-phase and V-phase distribution lines, and the current transformer 72 for short circuit current detection
An output is generated. This output is applied to the coil 60 of one lock solenoid 58. As a result, the solenoid 58 is maintained in the holding state as shown by A in FIG.

In this case, sufficient current is no longer supplied to the coil 60 of the other solenoid 58 to hold it, and the plunger 61 of that solenoid is moved by the spring 6.
2, the locking body 43 protrudes as shown in FIG. However, as described above (as shown in FIG. 4A), the locking body 43 in the other locking mechanism 42
Since the engagement between the engagement body 44 and the engagement body 44 is maintained (see FIG. 6C), the opening operation of the operating mechanism is prevented, and the switch 70 is prevented from being opened erroneously.

In the above-described operation, even if a short circuit occurs between any two phases of the three-phase distribution line, an output appears in at least one of the current transformers 72, 73, thereby preventing the switch from being erroneously opened. In addition, when a three-phase short circuit occurs, an output is generated in either current transformer, but in this case, both solenoids 58 are only kept in the holding state, and the holding mechanism 41 is in the state shown in FIG. 3. is kept as is.

(3) When the three-phase distribution line becomes non-voltage and no short circuit current flows due to a trip at the substation In this case, no current flows through the coil 67 of the holding magnet 66. Also, no current flows through the coil 60 of each lock solenoid 58. Therefore, the plungers 61 of both lock solenoids 58 are projected by the force of the spring 62, and the locking body 43 and the engaging body 44 are disengaged from each other. In this case, the biasing force of the spring 39 or the spring 15 is applied to the shaft 52 via the various shafts 7, 21 or a large number of levers, and biases the engaging body 44 downward, so that the above-mentioned engagement When the spring 39 or the spring 15 comes off, the biasing force of the spring 39 or the spring 15 rotates the operating shaft 7 in the opening direction, that is, the direction shown by the arrow A in FIG. 3, and each contact 71 in the switch 70 is opened. It becomes an open state as shown in FIG. 1 or FIG. 6A.

As described above, in the present invention, when the three-phase distribution line is energized, the closing magnet 17 is activated to close the switch 70, and the holding magnet 66 is activated to protrude from the shaft 52. The locking body 43 is engaged with the engaging body 44 that is located on the shaft 5.
Prevent rotation of 2. This has the advantage that the closing magnet 17 can be maintained in the closed state.Furthermore, even when a large current flows through the load due to a short-circuit accident and the voltage to the closing magnet 17 drops, both of the lock solenoids 58 are connected. , or at least one of the lock solenoid 58 is supplied with electric power from the current transformers 72 and 73, so that at least one of the two interlocking rods 63 is operated to operate the engaging body 44. This has the advantage of preventing the engagement between the locking body 43 and the locking body 43 from being disengaged, and has the effect of keeping the switch 70 closed while a short-circuit large current is flowing.

Moreover, in the present invention, as is clear from FIG. A connecting portion consisting of a connecting piece 69 disposed in the elongated hole 64 so as to be movable in the longitudinal direction of the elongated hole is interposed, and each of the interlocking rods 6
3 is equipped with a lock solenoid 58 that receives power from current transformers 72 and 73 on different lines, so the short circuit accident described above is an accident in which a large current flows only to one of the current transformers (two-phase short circuit). In either case, the power value input to each lock solenoid 58 is They are individual, and have the advantage that there is no superimposed negative effect between current transformers as in the conventional case. This has the revolutionary effect of making it extremely easy to coordinate OCR settings at substations.

[Brief explanation of the drawing]

The drawings show an embodiment of the present application, in which Fig. 1 is a perspective view of the operating mechanism in the open state, Fig. 2 is a vertical sectional view of the lock solenoid, Fig. 3 is a perspective view of the operating mechanism in the closed state, and Fig. 4 is a perspective view of the operating mechanism in the open state. The figure is a perspective view of the holding mechanism showing the non-blocking state in the event of a short circuit, and Figure 5 is a circuit diagram.
FIG. 6 is a diagram showing the basic structure of the mechanism. U, V, W... Distribution line, 70... Switch, 17
...Insertion magnet, 79...Rectifier, 66...
...Holding magnet, S...switch.

Claims (1)

[Claims] 1. Connect the plunger 19 of the closing magnet 17 to the switch 70 installed in the three-phase distribution line, and connect the coil 18 of the closing magnet 17
is connected to the power source side of the three-phase distribution line switch 70, so that the switch 70 is operated to close or open depending on the presence or absence of voltage of the three-phase distribution line, and is connected to the plunger 19. The shaft 52, which is provided to rotate in conjunction with the operation of the plunger 19, and the coil 67, which is connected to the power source side of the three-phase distribution line switch 70, are energized or not. A holding magnet 66 that operates the plunger 68, and two engaging bodies 44 that project from the shaft 52, respectively.
and the plunger 68 of the holding magnet 66.
are connected to each other via an interlocking rod 63, and when the holding magnet 66 is activated, it engages with each of the engaging bodies 44 separately to stop the rotation of the shaft 52, and In a switch holding device for a three-phase distribution line, which includes two locking bodies 43 designed to prevent the switch 70 from opening, the two interlocking rods 63 and the plunger 68 of the holding magnet 66 are provided. The connection is made through a connecting part consisting of a long hole 64 provided on one side and a connecting piece 69 provided on the other side and disposed within the long hole 64 so as to be movable in the longitudinal direction of the long hole. Furthermore, for each interlocking rod 63, current transformers 72 and 73 for short-circuit current detection, which are attached to mutually different lines on the load side of the three-phase distribution line switch 70, respectively. When each lock solenoid 58 receives electric power from the respective current transformers 72 and 73, the corresponding interlocking rod 63 locks the locking body 43 by the return of the holding magnet 66. A holding device for a switch in a three-phase power distribution line, characterized in that it is attached so as to stop the switch from moving toward the releasing side.