JPS61203735A - Distribution line carrier ground return device - Google Patents

Abstract

PURPOSE:To simplify the signal processing of a transmitter-receiver by providing a voltage discriminating function passing through a signal voltage only, not passing through a commercial voltage to a coupler. CONSTITUTION:Since the primary neutral point of a differential transformer 12 is grounded, a complex number voltage V outputted at the secondary winding is proportional to a voltage Va+Vb in impressing complex number voltage Va, Vb to the primary winding of the transformer 12 at reception. Thus, no commercial voltage is inputted/outputted through the differential transformer 12 but only the signal voltage is inputted/outputted. At transmission, since the transformer 12 hardly passes through the commercial voltage, when the signal voltage is impressed to the secondary side of the transformer 12 from the transmitter-receiver 9, a common mode signal is sent to each phase of a low voltage distribution line (10a, 10b). Thus, only the signal voltage is processed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention provides a coupler for coupling a power distribution line and a transmitter/receiver in order to inject a signal into the power distribution line or extract the signal from the power distribution line. The present invention relates to a distribution line transport ground return device provided therein.

[Conventional technology]

FIG. 4 is a diagram showing a conventional distribution line conveyance ground return device disclosed in, for example, Japanese Utility Model Application Publication No. 57-165041. capacitor shunt consisting of variable capacitor 4, 5
is a signal detection capacitor, 6 is a receiver, and T is a power distribution line.

Next, the operation will be explained. Commercial voltage and signal voltage are heavily applied to the distribution line, and these applied voltages are divided by a coupler that also includes a high-withstand voltage capacitor 1, a capacitor shunt 22, and a signal detection capacitor 5, and the divided voltage is It is received by the receiver 6.

[Problem that the invention seeks to solve]

In conventional power distribution line carrier earth return devices, the voltage on the power distribution line is simply divided by the impedance of the coupler.

In order to input this voltage to the receiver, the voltage input to the receiver side was a combination of the commercial voltage and the signal voltage. Moreover, by connecting a coupler to the gap for transmitting a signal from a transmitter (not shown) to the power distribution line 7, commercial voltage is applied to the transmitter.

Therefore, it is necessary to remove the influence of unnecessary commercial voltage on the transmitter/receiver side and pass only the signal voltage.
The problem was that the equipment became complicated.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a distribution line carrier ground return device that processes only signal voltages on the transmitter/receiver side without considering the influence of commercial voltage.

[Means for solving problems]

The distribution line carrier ground return device according to the present invention has a voltage discrimination function that allows only the signal voltage to pass through the coupling portion without passing the commercial voltage.

[Effect]

The coupler according to the present invention simplifies the configuration of the transceiver by applying only the signal voltage to the transceiver.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG.

In Fig. 1, 8 is a high-voltage distribution line, 9 is a transmitter/receiver, and 10 is a high-voltage distribution line.
a is the low voltage distribution line a phase, IQb is the low voltage distribution line phase, 11/
d, a low-voltage distribution line grounding line, a differential transformer as an 12Fi coupler; 13, a grounding line connected to the middle point p of the primary side of the differential transformer; 14, a pole transformer;

Next, the operation of one embodiment of the present invention will be explained.

(a) Since the primary side center point pt of the differential transformer 12 is grounded during reception,
The complex voltages applied to both ends of the primary side of the differential transformer 12 are denoted as Va and Vb, respectively.

The complex voltage V output to the secondary side of the differential transformer 12 is Va
It is proportional to 10 Vb. Therefore, the commercial voltage is not input/output through the differential transformer 12t, and only the signal voltage can be input/output.

By the way, regarding the commercial voltage of the low-voltage distribution lines 10a and 10b, the grounding wire 11t and the pole transformer 1402 sandwiching the
Between the two phase voltages Va commercial and vb commercial on the next side, Va
Because of the relationship of commercial + vb commercial = O, differential transformer 1
The commercial voltage V commercial does not appear on the 202 secondary side.

On the other hand, the signal voltage by the earth return device is low voltage distribution @10
Since it is applied equally to each phase of a and 10b, the signal voltage of the low-voltage distribution line is equal to , there is a relationship of Va signal = vb signal 0 signal. Therefore, a signal voltage V signal proportional to ÷a signal +÷b signal is output to the secondary side of the differential transformer 12.

) When sending This is because the differential transformer 12 does not pass commercial voltage.

If a signal voltage is applied from the transmitter/receiver 9 to the secondary side of the differential transformer 12 without considering the influence of commercial voltage, the low voltage power distribution l11
It is possible to send signals of the same phase to each phase of 10a and 10b.

In this way, by providing the coupler with a voltage discrimination function, it is possible to remove the influence of the commercial voltage and process only the signal voltage.

In the above example, the differential transformer 12 as a coupler was provided with a signal voltage discrimination function, but as shown in FIG.
The filter of the coupler consisting of the coupling impedance 15 and the filter 16 may be provided with a discrimination function.

In addition, as shown in FIG. 3, a filter IT is installed at the midpoint P on the primary side of the differential trough 120 to block the commercial frequency and pass the signal frequency.
may be connected in combination. In FIGS. 2 and 3, the same parts as in FIG. 1 are designated by the same reference numerals, and their explanation will be omitted.

〔Effect of the invention〕

As described above, according to the present invention, since the coupler is provided with a signal voltage discrimination function, only the signal voltage can be injected and extracted without passing the commercial frequency voltage. This simplifies signal processing in the transceiver. The transceiver can be easily configured.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a diagram showing a distribution line carrier ground return device according to an embodiment of the present invention, FIGS. 2 and 3 are diagrams showing other examples of the present invention, and FIG. The figure shows a conventional power distribution line carrier ground return device. 9 is a transceiver, 10a and 10b are distribution lines, 12 is a coupler (differential transformer), and 15.16 is a coupler (coupled impedance, filter). 2. In the figures, the same reference numerals indicate the same or corresponding parts. Patent applicant: Mitsubishi Electric Corporation Figure 4

Claims (1)

[Claims] In order to inject a signal into the distribution line or extract the signal from the distribution line, in a distribution line carrier ground return device provided with a coupler for coupling the distribution line and the transmitter/receiver, the commercial voltage is not passed and the signal voltage is A distribution line conveyance ground return device characterized in that the coupler is provided with a voltage discrimination function that allows only the voltage to pass through.