JPS5832317A - 3-phase switching device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a three-phase automatic opening m
Regarding l@place.

Generally, in switching equipment, there is a so-called current cut-off phenomenon in which the current is forcibly cut off at the current zero point at the time of cut-off, but if this current cut-off occurs when a small current is cut off with a delay, an overvoltage occurs. However, there is no need to worry too much about overcurrent caused by simple current interruption. However, in recent years, the opening/closing surge Jr.! Research on elephants has progressed, and in addition to the above-mentioned overvoltage caused by current interruption, there are
The existence of the next opening and closing surge phenomenon has been revealed.

(■) Voltage hilt-up development due to repeated re-ignition (I) Three-phase simultaneous break-down phenomenon (1') refers to the transient voltage H Unable to withstand it, it re-ignites, and as a result of this repeated re-ignition, Den (1) gradually becomes more sensitive.

In (1), when one phase is cut off at the current zero point and restarted,
Other phases are also strong! This is a phenomenon in which the current is cut off and a current cutoff larger than the cutoff current value specific to the vacuum switch is caused.

By the way, in the power transmission system, a comparatively simple accelerator whose function is to supply phase-lag capacity is installed in parallel, and instead of a synchronous phase modifier, it can be used alone or for power use. In general, a 3-phase reactor is connected to a 3-phase reactor, △ or Y, and is connected directly to the power transmission system or to the tertiary side of a transformer and turned on and off as appropriate. When the small current flowing through the accelerator is cut off by a three-phase switch, the phenomenon (I) (1) may occur.

This point will be explained using the conventional type shown in FIGS. 1 and 2. First, FIG. 1 is an example of a control circuit for operating the operating mechanism of the W4 closure. This control circuit has one end connected to a positive polarity DC power source and the other end connected to a negative polarity power source through the contactor's excitation coil 1, etc., in order to open the switching device. Junction switch 2
At the same time as the auxiliary switch 3.4.5 and the contactor switch 6 are turned on, the contactor switch 6 is turned on. When these switches are turned on, voltage is applied to the motors 7, 8, and 9, and the operating mechanism □ is driven.

FIG. 2 shows an example of the structure of an electric spring operation device for one phase in a three-phase switch. That is, the rotational force of the motor 7 is transmitted to the ratchet 12 via the speed reducer 10 and the eccentric shaft 11. The ratchet 12 meshes with the teeth 23 and feeds in one direction, compressing the drive spring 18 via the wheel 15 and the connecting cams 16 and 17. The drive spring 18 is most compressed when it is aligned with the center line of the arm of the connecting cam 17, and is released immediately thereafter. When release is started, the connecting cam 17 is released from the connecting cam 16 and at the same time connects with the connecting cam 20 that is directly connected to the equipment main shaft 19, rotates the equipment main shaft 19, and operates the switch main body.

In a conventional switch, an electric spring operation device as described above is provided for each phase, and a drive motor 7.
The electric spring operation device of each phase was configured to immediately start the opening operation at the same time as the switch for 8.9 was turned on. For this reason, in the conventional type, the first phase is re-ignited, harmonic current is superimposed on the other two phases, and a current zero point is forcibly created, causing three phases to be cut off at the same time. There was a drawback that such a surge overvoltage occurred.

The present invention was proposed in order to eliminate the drawbacks of the prior art as described above, and it is an object of the present invention to provide a three-phase switchgear in which the isolation time of each phase is staggered to avoid simultaneous shutoff of three phases. With the goal.

The present invention will be described below with reference to an embodiment shown in FIG.

Figure 3' shows the operating device for the first phase R111.1. The same parts as those of the conventional operating device are denoted by the same reference numerals, and the description thereof will be omitted. In this phase of the operating device, a position detection piece 2 for detecting the rotational position of the camshaft 22 is attached to the second connecting cam 17 connected to the drive spring 18.
8 is provided.

This detection piece 23 is combined with a position detection device [24] that generates a signal by optical or electromagnetic coupling when the detection piece 23 reaches a predetermined position.

On the other hand, other two-phase operating devices other than those shown in FIG. 3 have a configuration as shown in FIG. 4. That is, in addition to the conventional operating device, these phase operating devices include a locking lever 25 fixed to one end of the camshaft 22;
5. This catch 26! It is rotatably attached to the support shaft 27,
At the opposite end of the catch 26 from the locking lever 25, a circuit coil 28 and a core 29 which is attracted and driven by the circuit opening coil 28 are arranged in stages.

Further, the lever 15 is provided with a limit switch 52 for detecting its rotational position.

Next, the operation of the opening/closing device of the present invention configured as described above will be explained.

First, when the motors of each phase shown in FIGS. 3 and 4 are driven by the control circuit shown in FIG. , is transmitted to the wheel 13 and rotates it. Furthermore, this rotational force is transmitted to the drive spring 18 via the link 14, the lever 15 and the connecting cams 16, 17, and causes the drive spring 18 to be compressed and energized. The drive spring 18 is most compressed when it is aligned with the centerline of the am of the connecting cam 17.

Then, the first phase operating device shown in FIG.
The drive springs 18 for the second and third phases shown in the figure are in a compressed and stored state without being released because the catch 26 is engaged with the locking lever 25 provided on the hm shaft. Opening/closing operations are not performed either. After that, when the forceps 11 in the first phase device rotate and the position detection piece 23 comes to a preset position, the position detection device 24 generates a signal, which causes the second phase to move. , the circuit-opening coil 28 of the third phase device is excited, the catch 50 is rotated by the core 29 driven by this electromagnetic force, and the lock lever -25 is unlocked.

Therefore, the first phase is l! After the release, the second and third phase opening operations are performed with a delay of the set II period.

As explained above, in the present invention, after the first phase is released from the state in which the spring is compressed and stored, and the contact point of the breaker is opened, the other two phase driving springs are stopped by the catch. is configured to operate with a delay and open the cut-off parts simultaneously or sequentially, so when the R-phase current is cut off, the current flowing to the other phases is cut off due to the re-ignition of the cut-off part of one phase. It becomes possible to prevent the so-called three-phase simultaneous new phenomenon.

[Brief explanation of the drawing]

FIG. 1 is a control circuit diagram for operating a conventional operating mechanism, FIG. 2 is a perspective view of a conventional one-phase electric spring operating device, and FIG. FIG. 4 is a perspective view of the operating device of the delayed operating phase in the present invention. 7...Motor, 10...Reduction device, 11...Eccentric shaft, 13...Wheel, 14...Link, 15...
- Lever, 16.17... Connection hm, 23... Detection piece, 24... Position detection device, 26... Kit, 28
...for opening the circuit.''Il.

Claims (1)

[Claims] In a switching device connected to a three-phase circuit, the first phase operating mechanism includes a detection piece for detecting the W@ separation position, and a detection piece for detecting the (DI) of this detection piece for detecting the W@ separation position. A position detection device that emits a signal to two phases is provided, and the operation mechanism for the second and third phases receives the signal from the position detection device and outputs a signal to the second and third phases.
A three-phase switchgear characterized by having a means for starting phase separation.