JPS62235829A - Low voltage distribution line carrier transmission system - Google Patents

Abstract

PURPOSE:To attain the signal transmission with high reliability by providing both the metallic circuit system and the earth return system and using the other system to send a signal when one system does not function. CONSTITUTION:A signal voltage sent from a transmitter 1a i: applied between low distribution lines 3 through a filter 2a not passing the commercial frequency but passing the signal frequency, distributed through the line 3 and received by a receiver 1b through a filter 2b at the receiving end. On the other hand, a signal is injected between distribution lines from the transmitter 1a and also between a distribution line and ground from the transmitter 1c. That is, the signal voltage sent from the transmitter 1c is applied between the low voltage distribution line 3 and ground through the filter 2c not transmitting the commercial frequency but transmitting the signal frequency. The applied signal voltage is sent through the low voltage distribution line 3 and received by a transmitter ld through a filter 2d at the sending end.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a transmission system for carrying low-voltage power distribution lines.

It is something to do. , , [Prior Art] FIG. 8 is a conceptual diagram showing a conventional low-voltage distribution line carrying metal circuit system. In Figure 8, % (IIIL)1(1
1 company transmitter, (2a) and (lb) are filters that block commercial frequencies and pass signal frequencies, (3; is a low-voltage distribution line, +41 is a pole transformer, and 1lil is a load.

On the other hand, FIG. 8 is a conceptual diagram showing a conventional low-voltage power distribution line transportation ground return system. In Figure 3, (la) e (16) is a transmitter/receiver, (2c) e (2d) is a filter that blocks commercial frequencies and passes signal frequencies, (3: is a low-voltage distribution line, and (41 is a pole-mounted transformer). , 161ti is a filter that passes commercial frequencies and blocks signal frequencies.

Next, the operation of the metal circuit system shown in FIG. 8 will be explained, taking as an example the case of upstream transmission.

In Fig. 8, the signal voltage emitted from the transmitter (la) is filtered through the filter (which passes the signal frequency but not the commercial frequency).
1a) A signal voltage is applied between the lines of the low-voltage distribution line (31) through the t-t. Received.

Next, the operation of the ground return method shown in FIG. 8 will be explained using an example of uplink transmission. In Figure 3, the transmitter (lc
) The signal voltage transmitted from the low-voltage distribution line (3
1 and the ground.The applied signal voltage is transmitted through the low-voltage distribution line (3) and passed through the filter C2d at the receiving end.
)k is received by the receiver (ld).

[Problem that the invention seeks to solve]

The conventional low-voltage distribution line carrying wire mesh circuit system is configured as described above, so if there is a load with low impedance relative to the signal frequency, such as a capacitor, between the lines of the distribution line, the signal voltage will be shorted by the load. The disadvantage was that the signal could not be transmitted. On the other hand, since the conventional low-voltage power distribution line return-to-ground system is configured as described above, it has the disadvantage that it cannot be used in places where grounding cannot be established, such as in apartments.

The present invention has been made to solve the above-mentioned problems, and its purpose is to provide a method that allows signal transmission even when the load impedance relative to the signal frequency is small and even in places where grounding is difficult.

[Means for solving problems]

The low-voltage distribution line transportation method according to the present invention combines a metal circuit method and a ground return method for low-voltage distribution line transportation.

[Effect]

The low-voltage distribution line conveyance system of the present invention applies a signal both to the line of the low-voltage distribution line and between the low-voltage distribution line and the earth, and the signal is transmitted through both the metal circuit and the earth return circuit and is received. Ru. Therefore, depending on the form of the low-voltage power distribution system, even if either the metal circuit method or the ground return method cannot be used, signal transmission is possible if the other method can be used for transmission and reception.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. In Figure 1, (la), (1'b), (lc), (14)
is a pole transformer, (6) is a load, (61 is a filter that passes commercial frequencies and blocks signal frequencies, (7a) (W
b) is a first transformer having a primary coil (7al) (7t+1) and a secondary coil (?a(v'bg));
(70) (7(1) is the primary coil (Tax) (wax)
and the secondary coil (7c2) (?d2) and the completely blind second transformer, (8a) (8b) is the III transformer (7a)
(Wb) primary coil (val) (vbl) and second transformer (7c) (?cL) primary coil (oct) (a
This is a connection line that connects each connection point with 1 and the low voltage distribution line (3) to which the filter (6) is connected.

In Fig. 1, the signal voltage emitted from the transmitter (la) is filtered through a filter (1) that passes the signal frequency but not the commercial frequency.
a) is applied between the lines of the low voltage distribution line (3). The good signal voltage is transmitted through the low voltage distribution line (31, filter (9m) at the receiving end) and then passed through the receiver (Fb).
received at On the other hand, at the transmitting end, a signal is not only injected from the transmitter (1a) between the lines of the power distribution line as described above, but also a signal is injected from the transmitter (lc) between the power distribution line and the ground. That is, the signal voltage transmitted from the transmitter (la) is applied between the low voltage distribution line 1ull and the ground through the filter (2C) that passes the signal frequency but not the commercial frequency. The signal is transmitted through an electric wire (31) and is received by a receiver (1d) through a filter (2d) at the receiving end.

At the receiving end, if either the receiver (1b) or the receiver (ld) can receive normally, the transmission is considered to have been successful.

In the above embodiment, the metal circuit type and ground return type transmitter/receiver are separated for clarity of explanation, but they may be incorporated into the same device. Furthermore, for transmitters and receivers in places where grounding is not possible, the earth return type part can be omitted and only the metal circuit type part can be installed.

〔Effect of the invention〕

As described above, according to the present invention, since both the metal circuit method and the ground return method are used in low-voltage distribution line transportation, signal transmission with high reliability can be achieved. In addition, with the conventional ground return method, it was not possible to install the transmitter/receiver in a place where it could not be grounded, but even in that case, according to this method, the transmitter/receiver can be installed by attaching only the metal circuit type part. There is an effect that can be done.

[Brief explanation of drawings]

Fig. 1 is a connection diagram showing a low voltage distribution line transport system according to the present invention, Fig. 3 is a connection diagram showing a conventional low voltage distribution line transport metal circuit system, and Fig. 8 is a connection diagram showing a conventional low voltage distribution line transport method using a ground return route. FIG. In the figure, (la), (lb), (ta), (ta)
is the transmitter/receiver% (ta), (jlb), (!lc), (
+4) is a filter that blocks commercial frequencies and passes signal frequencies, (3) is a low-voltage distribution line carrier % (4) is a pole-mounted transformer, (61 is a load, (61 is a filter that passes commercial frequencies and blocks signal frequencies) It is a filter. In the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] A low-voltage distribution line characterized by having both a metal circuit method and a ground return method as signal transmission path methods for carrying low-voltage power distribution lines, and in the event that one method does not function, signal transmission is performed using the other method. Transport transmission method.