JPH07123551A - Phase detector for overhead transmission/distribution line and using method thereof - Google Patents

Abstract

PURPOSE:To allow phase detection without applying any voltage to an overhead transmission/distribution line by using a ground rod incorporating a circuit comprising diodes connected in series and parallel, a battery, a buzzer and a switch connected in series with the parallel connection of diodes, and a main switch connected in parallel therewith. CONSTITUTION:The phase detector is connected, at one end thereof, with a power line A and, at the other end thereof, with a steel tower at site. A diode 3 is conducted during negative half cycle to pass a current and when the inner resistance of power supply is low, a battery 6 also feeds a current and thereby a buzzer sounds. During positive half cycle, reverse voltage is applied to the diode 3 which is thereby rendered nonconductive to interrupt current. Since the battery 6 and the buzzer 5 are not fed with overvoltage or overcurrent, phase detection can be conducted. In other words, phase detection of an overhead transmission/distribution line can be effected without applying actual voltage and thereby the manhours can be saved while avoiding ground fault and the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phase detector used for phase detection after completion of construction of an overhead power transmission and distribution line and a method of using the phase detector.

[0002]

2. Description of the Related Art In conventional phase detection of overhead transmission and distribution lines, after completion of the overhead line work, the jumper wire is disconnected at a location farther from the construction section as seen from the power source, and first, only one phase is connected to turn on the power source.
If the phase is turned on and OK, the power is temporarily turned off, then the second phase is connected, the power is turned on, and this is repeated sequentially. At this time, if you turn on the power from the power supply side and forget to remove the ground, a ground fault will occur, otherwise a voltage will be generated in a predetermined phase, so check this from the voltage divider of the load side substation. The method of doing was taken.

[0003]

In the above-mentioned conventional method, if the user forgets to remove the ground, a ground fault may occur, which may damage the equipment at the substation. There was a problem that the place where the construction was done could not be confirmed.

Further, in the above-mentioned method, not only is it necessary to operate the actual power transmission equipment from the substation to perform power transmission for phase detection, but also to disconnect the jumper wire on the way, so that the jumper part will be disconnected later. There was a risk of problems such as forgetting to tighten the clamp bolts.

[0005]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems and enables phase detection without actually applying a voltage to the overhead transmission and distribution line, and saves the labor. And its use are provided, and the feature is that diodes are connected in series and in parallel, and a battery, a buzzer and a switch for a buzzer are connected in series to one of them in parallel, and a main switch is provided in parallel to them. It is in the phase detection device and the method of using it which built in the circuit into the ground rod.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a circuit configuration diagram of a concrete example of a phase detection device of the present invention in a normal ground state, and FIG. 2 is a circuit configuration diagram of a measurement state (phase detection state). As shown in the drawing, the diodes 3 are connected in series and in parallel, and in one of the parallel connection,
A battery 6, a buzzer 5, and a buzzer switch 4 are connected in series, and a main switch 7 is connected in parallel to these.
Are connected. The circuit thus constructed is incorporated into the grounding rod 1 having a fitting 2 for attaching to the overhead transmission and distribution line A at its tip to form a phase detector.

As the diode 3, a diode that withstands a voltage induced by an electromagnetic induction current is used. However, since the electromagnetic induction current is large and the diode 3 is heated if it is left in a grounded state for a long time, the main switch 7 is provided as a heating prevention, and when the device is connected to the overhead transmission and distribution line A, As shown in FIG. 1, the main switch 7 is turned on and the buzzer switch 4 is turned off. Also, the buzzer switch 4 is usually
The diode 3 can be protected without being energized for a long period of time by turning it off as shown in FIG.

[0008]

Consider the state where both ends of the circuit of FIG. 1 are connected to another AC power source through resistors. At this time, the diode becomes conductive in the negative half cycle, so that a current flows, and at the same time, if the internal resistance of this power supply is small, the voltage due to the voltage of the battery also flows, and the buzzer sounds. Conversely, in the positive half cycle, the reverse voltage is applied to the diode, so the diode becomes non-conductive,
No current flows, and excessive voltage and current do not flow to the battery and buzzer. This is an equivalent circuit that represents the case where the electromagnetic induction current induced in the power line of another line flows into the power line and the power line part becomes the power source.Therefore, the same effect is obtained when this circuit is connected to the power line. can get.

In the present invention, as shown in FIG. 1, the above-mentioned circuit is incorporated into a grounding rod, one end is attached to a power line at the construction site, and the other end is grounded to a steel tower, so that the power line is at another point. If it is grounded by the grounding rod 11 at,
An electric circuit as shown in FIG. 2 is configured, and a buzzer sounds to confirm the ground fault condition. If the power line is not in the grounded state, confirm each phase of the power line at a different point by sequentially grounding each phase with a grounding rod to confirm which phase is connected to the test equipment and confirms continuity. You can That is, the phase can be detected.

In the present invention, the number of diodes used is determined so that it can withstand the voltage induced by the electromagnetic induction current and the reverse withstand voltage of the diodes used.
Further, if the current capacity of the diode is small, a plurality of diodes may be used in parallel as shown in FIG. The diode connected in series is for rectifying the current induced from the opposite line to the power line under construction, and prevents the reverse current from flowing.

[0011]

As described above, the phase detection of the overhead transmission and distribution line using the phase detector of the present invention can be performed without actually applying a voltage, and the labor required in the past, for example, the jumper section is required. It is possible not only to omit the disconnection and contact to the substation for applying voltage, but also to avoid a ground fault accident that occurs when you forget to remove the ground, and prevent damage to the power transmission and distribution equipment. There are effects such as doing.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram of a specific example of a phase detector of the present invention in a normal ground state.

FIG. 2 is a circuit configuration diagram of a concrete example of the phase detector of the present invention in a phase detection state.

FIG. 3 is a circuit configuration diagram of another specific example of the phase detector of the present invention.

[Explanation of symbols]

 1 Grounding rod 2 Mounting bracket 3 Diode 4 Buzzer switch 5 Buzzer 6 Battery 7 Main switch

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Hisashi Iwamura Hisashi Iwamura 1-16-25 Koyasu-cho, Hachioji, Tokyo Tokyo Electric Power Company Tama Branch (72) Inventor Tatsue Nakajima 1-chome, Koyasu-cho, Hachioji, Tokyo No. 16-25 Tokyo Electric Power Company Tama Branch (72) Inventor Moneo Takeyama 2-1038 Misumicho, Higashimurayama City, Tokyo Tokyo Electric Power Co., Ltd. Musashino Engineering Office (72) Inventor Yoshiyuki Tagami Hyogo Prefecture 2 at 20 Toda, Kitagawara, Itami-shi Within Asahi Metal Seiko Co., Ltd. (72) Inventor Mikihiko Okano 1-3-1 Shimaya, Konohana-ku, Osaka Sumitomo Electric Industries, Ltd. (72) Inventor Takeshi Kawamura 1-3-3 Shimaya, Konohana-ku, Osaka City Sumitomo Electric Industries, Ltd. Osaka Works

Claims (2)

[Claims] 1. A diode is connected in series and in parallel, and a battery, a buzzer and a switch for a buzzer are connected in series to one of the paralleled ones, and a circuit in which a main switch is provided in parallel to these is incorporated into a ground rod. A phase detector for overhead transmission and distribution lines. 2. The phase detector according to claim 1 is attached to an overhead transmission and distribution line, and the other end is grounded to a steel tower to confirm the presence or absence of a ground fault. A method of using a phase detector, wherein the phase is detected by grounding the phase.