JP3319877B2 - Power supply method and apparatus for wired broadband transmission line - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for feeding power to a relay amplifier inserted in a broadband transmission line. In particular, the present invention relates to a power supply method that is characterized by a power failure during a commercial power failure.

[0002]

2. Description of the Related Art Conventionally, as a broadband transmission line, C
There is a coaxial transmission line of the ATV system. A relay amplifier for amplifying a high-frequency signal is inserted into the CATV transmission line, and the relay amplifier is supplied with AC power superimposed on the high-frequency signal on a coaxial cable. In order to superimpose AC power on the coaxial cable, a power supply device is connected to the coaxial cable.

This power supply device receives power from a commercial power supply,
v, and the power is transmitted to the transmission line. The power supply device charges a battery and is provided for power failure of a commercial power supply. At the time of a power outage, the DC power output from the battery is converted into AC power using an inverter, the AC power is boosted using a transformer, and the boosted AC power is transmitted to a transmission line.

[0004]

However, the above-described power supply device requires an inverter and an output transformer for boosting the output of the inverter, and further converts a direct current into an alternating current when supplying power during a power failure. In addition, in the relay amplification, the alternating current is converted into the direct current, so that the power loss is increased and the capacity of the battery is increased. As a result, there is a problem that the power supply device becomes large and heavy.

[0005] For this reason, the power supply device cannot be mounted on the power pole, and the owner of the CATV system needs to install a private pole specifically for installing the power supply device. . Due to these circumstances, there were problems such as land acquisition for constructing private pillars and urban aesthetics.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to reduce the size and weight of a power supply device for a wired broadband transmission line.

[0007]

The invention according to claim 1 relates to a power supply method, wherein a relay amplifier rectifies AC power transmitted through a transmission line to form a DC power supply. At the point, the commercial power is stepped down to a predetermined AC voltage and transmitted to the transmission line, and the battery is charged with the commercial power, and the DC power output from the battery is transmitted to the transmission line when the commercial power fails. It is characterized by.

A second aspect of the present invention relates to a power supply apparatus used in the above-described power supply method. The power supply apparatus receives a commercial power supply and steps down the voltage to a predetermined AC voltage, and outputs the commercial power or the transformer. A charging circuit for charging a battery with AC power, a battery charged by the charging circuit, and an output terminal of a transformer or an output terminal of the battery and a power supply terminal to be transmitted to a transmission line, and commercial power is input. In the case of power failure, the output terminal of the transformer and the power transmission terminal are connected, and in the event of a power failure when commercial power is not input, the switching operation is performed to connect the output terminal of the battery and the power transmission terminal. And switch means for switching.

[0009]

The power supply device is connected to the transmission line at the power supply point during normal power supply. In this power supply device, the commercial AC power is stepped down to a predetermined AC voltage by a transformer, and the AC voltage is supplied to the transmission line. The switch means of the power supply device detects that commercial power is input, and connects the output terminal of the transformer and the power transmission terminal of the transmission line. In this state, the battery is charged by the commercial power or the AC output from the transformer. The relay amplifier inserted in the transmission path receives this AC power, converts it into DC power by a rectifier circuit, and operates with this DC power.

[0010] DC power is transmitted to the transmission line from a battery that is charged when the power supply device in the event of a commercial power failure is normal. When the switch means of the power supply device detects a power failure state of the commercial power supply, the output terminal of the battery and the power transmission terminal of the transmission line are connected. As a result, DC power is supplied to the relay amplifier. At this time, since the relay amplifier is provided with a rectifier for rectifying AC, even if DC is supplied, the power can be used without any trouble.

[0011]

As described above, the power supply device does not require an inverter for converting a battery voltage into an AC voltage during a power failure and a transformer for boosting the output of the inverter.
In addition, since the DC power is directly supplied to the relay amplifier from the battery, the power factor is better and the power loss is smaller than that of the AC, so that the capacity of the battery can be reduced. As a result, the power supply device can be reduced in size and weight.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to specific embodiments. FIG. 1 shows a configuration of a power supply device 100 connected to a CATV coaxial cable. Output terminal of this device
OT is connected to a coaxial cable via a power through filter (choke coil). 100 V AC of commercial power is applied to the input terminal IN of the transformer 11, and the relay coil 10 excited by the commercial power is connected to the transformer 11.
Are arranged between the input terminals.

The transformer 11 is a transformer for lowering the voltage from 100 V AC to 60 V AC. The output terminal T1 of the transformer 11 is connected to the relay contact A, and the output terminals T1 and T2 of the transformer 11 are connected.
A charging circuit 12 is provided between them. The output of the charging circuit 12 is supplied to a relay contact B via an overdischarge prevention circuit 14.
It is connected to the. The output of the charging circuit 12 is connected to the battery 13. The relay 15 has a function of switching and connecting the output terminal OT of the transmission line between the contact A and the contact B. When the commercial power is supplied and the relay coil 10 is excited, the relay 15 is in a state of connecting the contact A to the output terminal OT of the transmission line. In this state, B is connected to the output terminal OT of the transmission line.

On the other hand, the relay amplifier 200 is configured as shown in FIG. The input terminal RIN of the relay amplifier 200 is connected to a coaxial cable via a power separate filter (choke coil). A full-wave rectifier bridge 20 is connected to the input terminal RIN, and a smoothing capacitor 21 is connected between output terminals of the full-wave rectifier bridge 20. Then, the voltage between the terminals of the capacitor 21 is converted into a predetermined stable DC voltage (24 VDC) by the switching power supply circuit 22, and the voltage is applied to the high frequency amplifier circuit 23.

Next, the operation of the present system and the power supply device 100 will be described. When the commercial power supply AC100V is supplied to the input terminal IN of the power supply device 100 at the time of normal power supply, the relay coil 10 is excited,
The relay 15 is connected between the contact A and the output terminal OT. As a result, AC60V obtained by stepping down AC100V by the transformer 11 is supplied to the output terminal OT of the transmission line. Therefore, the relay amplifier 20
0 is supplied with a voltage of 40 to 60 V AC in consideration of the voltage drop in the transmission line. The AC voltage in this range is rectified by the full-wave rectifier bridge 20, and the rectified voltage is input to the switching power supply circuit 22 and is converted into a stable 24V DC by the circuit 22. Supplied to

On the other hand, the battery 13 of the power supply device 100 is charged via the charging circuit 12 by the output of the transformer 11. The output voltage of the battery 13 is DC48V.

When the commercial power supply 100 V AC is cut off, the relay coil 10 is de-energized, and the relay 15 is in a state of connecting the current sending terminal OT of the transmission line to the contact B. As a result, the transmission path is 48 VDC from the battery 13 via the overdischarge prevention circuit 14.
Is supplied. Therefore, a voltage of 35 to 48 V DC is supplied to the relay amplifier 200 in consideration of a voltage drop in the transmission line. The DC voltage in this range is applied to the full-wave rectifier bridge 2.
0, the DC voltage is input to the switching power supply circuit 22 as a voltage across the capacitor 21, is converted into a stable 24 V DC by the circuit 22, and the DC voltage 24 V DC is supplied to the high frequency amplifier circuit 23.

In the above embodiment, the battery 13
May be directly charged from a commercial power supply without passing through the transformer 11. Furthermore, the power failure is detected by the relay coil 1
Although the setting is performed at 0, the relay switch 15 may be controlled by the circuit 2 using another power failure detection circuit.

As described above, according to the present invention, during normal power supply, AC power obtained by stepping down the voltage of the commercial power supply, and when the commercial power supply fails, DC power is directly transmitted from the battery 13 of the power supply device 100 to the transmission line. Like that. Therefore, there is no need for an inverter for converting the DC voltage of the battery into an AC voltage and a transformer for boosting the output of the inverter, which are necessary for power supply during a power failure. In addition, since DC power is supplied, power loss is small, and the capacity of the battery can be small. As a result, the power supply device can be reduced in size and weight.

Therefore, the power supply device according to the present invention can be mounted on a power pole of a power company.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a power supply device according to a specific embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a relay amplifier of a CATV system supplied by the power supply device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 power supply device 10 relay coil 11 transformer 13 battery 15 relay 20 full-wave rectification bridge 22 switching power supply circuit IN input terminal OT power transmission terminal

Claims (2)

(57) [Claims] 1. A method for feeding power to a relay amplifier inserted in a wired broadband transmission line, wherein the relay amplifier rectifies AC power transmitted through the transmission line to form a DC power source. At the feeding point, the commercial power is stepped down to a predetermined AC voltage and transmitted to the transmission line, and the battery is charged with the commercial power.When the commercial power is cut off, the DC power output from the battery is transmitted to the transmission line. A power supply method for a wired broadband transmission line, characterized in that the power supply is transmitted to a wired broadband transmission line. 2. A power supply device for supplying power via a transmission line to a relay amplifier inserted in a wired broadband transmission line, comprising: a transformer for inputting commercial power supply and stepping down to a predetermined AC voltage; A charging circuit that charges a battery with AC power output from a transformer; a battery charged by the charging circuit; and an output terminal of the transformer or an output terminal of the battery and a power transmission terminal to the transmission line. When the commercial power is input, the output terminal of the transformer is connected to the power sending terminal, and when the commercial power is not input, the output of the battery is output. A power supply device for a wired broadband transmission line, comprising: a switch for switching between a terminal and the power transmission terminal.