JPS61264927A - Carrier equipment through low voltage distribution line - Google Patents

Abstract

PURPOSE:To attain signal carrier transmission with an optional frequency by inserting a filter in series with a ground line, allowing a sending station to use an oscillator for generating a signal voltage and receiving the signal voltage by the reception station through a coupling impedance, a ground line at the sending station and a coupling impedance at the reception station side. CONSTITUTION:A voltage of signal frequency generated from an oscillator 50 in the sending station 5 is sent to a grounding line 3 through a coupling impedance 7 connected between the station 5 and the grounding line 3. the signal voltage sent to the grounding line 3 does not flow to the grounding line 4 because of the presence of a filter 9 and detected by the reception station through the coupling impedance 8 connected between the reception station 6 and the grounding line 3. That is, the signal is sent from the sending station 5 to the reception station 6 via the grounding line 3. Thus, the signal transmission with high reliability is attained inexpensively.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a low voltage distribution line conveying device.

[Conventional technology]

FIG. 3 is a system diagram showing a conventional low voltage distribution line conveying device disclosed in, for example, Japanese Patent Application Laid-Open No. 57-132739.

In Figure 3, 1 is a column of high-quality earthenware, 2 is a low-voltage distribution line, and 3
is a grounding wire, 4 is a grounding path connecting the grounding wire 3 and grounding E, 5 is a transmitting station, 6 is a receiving station that inputs the detection output of the current transformer 12 installed in the connecting path 4, and 10 and 11 are low voltage distribution lines. A capacitor and a switch are connected in series between the electric wire 2 and the ground E, and this switch 11 is turned on and off by the transmitting station 5.

Next, the operation will be explained. When the switch 11 is closed by the transmitting station 5, a ground fault current flows through the capacitor 10. Since this ground fault current flows through the ground path 4 and the low voltage distribution line 2, it can be detected at the receiving station 6 via the current transformer 12. Therefore, if the reception station 6 detects the presence or absence of a ground fault current, the important state of the switch 10 can be determined. A signal can be transmitted from the transmitting station 5 to the receiving station 6 using the low voltage distribution line 2.

[Problem that the invention seeks to solve]

Since the conventional low-voltage power distribution line carrying device is configured as described above, the low-voltage power distribution line, which has a large amount of noise, must be used as a signal path as a transmission path. Since the ground fault current is artificially applied to send the signal, it affects the ground fault relay.
Problems include that only commercial frequencies can be used as signal carrier waves, and that it cannot be applied to power distribution systems with connected grounding.

This invention was made to solve the above problems, and uses a low-noise grounding wire as a signal path.
The purpose of the present invention is to obtain a low-voltage distribution line carrier device that does not affect ground fault relays, can transmit signals using signal carrier waves of any frequency, and can be applied to distribution systems with connected grounding.

[Means for solving problems]

The low voltage distribution line carrier device according to the present invention inserts a filter in series in the grounding path of the grounding line, generates a signal voltage with an oscillator at the transmitting station, and combines the coupling impedance of the transmitting station side, the grounding line, and the receiving station side. This allows the receiving station to receive the signal voltage through impedance.

[Function] In this invention, the voltage generated from the oscillator of the transmitting station is detected at the receiving station through the coupled impedance of the transmitting station, the grounding wire, and the impedance of the receiving station, and the signal is transmitted through the grounding wire. transmitted from the transmitting station to the receiving station,
Low voltage power distribution? Avoid using fM as a signal transmission path.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. 1, in which the same parts as in FIG. 3 are denoted by the same reference numerals.

In the first factor, one end of the transmitting station 5 is connected to the ground line 3 via the coupled impedance 7, and the other end is connected to the ground E. One end of the receiving station 6 is connected to the connection line 3 via a coupling impedance 8, and the other end is connected to ground E.

The ground path 4 is grounded via a filter 9 that has a low impedance for commercial frequencies and a high impedance for signal frequencies.

Next, the operation will be explained. The signal frequency voltage generated from the oscillator 50 in the transmitting station 5 is connected to the transmitting station 5 and the grounding wire 3.
is transmitted onto the ground line 3 through a coupled impedance 7 connected between the two. The signal voltage transmitted on the grounding line 3 does not flow to the grounding path 4 because of the filter 9, but is detected at the receiving station through the coupled impedance 8 connected between the receiving station 6 and the grounding line 3. be done. In other words,
ground? f! A signal can be transmitted from the transmitting station 5 to the receiving station 6 via A3.

In Figure 2, grounding paths 4m and 4b are provided at two locations on the grounding wire 3.
Another embodiment of the present invention is shown in which filters 9m and 9bt are inserted in series in each ground path.

In each of the above embodiments, the cases where the grounding path 4 is provided at one location (Fig. 1) or two locations (Fig. 2) have been explained, but when the grounding path 4 of the grounding wire 3 is provided at two or more locations. However, this can be overcome by inserting filters 9 in series in each ground path, which is one of the advantages of this low-voltage distribution line carrying device.

〔Effect of the invention〕

As described above, according to the present invention, since the grounding wire is configured to be used as a signal transmission path, the device does not need to withstand voltage, there is less noise, there is no adverse effect on the ground fault relay, and highly reliable signal transmission is possible. Transmission can be done inexpensively. Another advantage is that any signal can be transmitted from the oscillator of the transmitting station.

[Brief explanation of drawings]

FIG. 1 is a system diagram showing a low-voltage distribution line carrying device according to one embodiment of the present invention, FIG. 2 is a system diagram showing another embodiment of the present invention, and FIG. 3 is a system diagram showing a conventional low-voltage distribution line carrying device. It is a system diagram. 2 is a low voltage distribution line, 3 is a grounding line, 4 is a grounding path, 5 is a transmitting station, 6 is a receiving station, 7 and 8 are coupling impedances, 9 is a filter, and 50 is an oscillator. In addition, in the figures, the same reference numerals indicate the same or corresponding parts. Patent applicant Mitsubishi Electric Corporation Representative Patent attorney 1) Hiroshi Sawa; (2 others)
“ Figure 1 Procedural Amendment (Voluntary) 13□060・♂・2Q 8

Claims (1)

[Claims] A transmitting station whose one end is connected to the ground wire of a low-voltage distribution line via a coupled impedance and the other end is grounded; and a transmitting station which is remote from the transmitting station and whose one end is connected to the ground wire via a coupled impedance and the other end is grounded. a receiving station, a filter connected in series to the ground path connecting the ground line and the ground, and having a low impedance for commercial frequencies and a high impedance for signal frequencies; A low-voltage distribution line carrying device equipped with an oscillator that transmits.