JP2611459B2 - Power supply - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device, and more particularly to a power supply device for supplying power to a load having two input power supply systems, such as a subscriber circuit of an exchange.

[Conventional technology]

 FIG. 2 shows an example of this type of conventional power supply device.

A station power supply 1 used for communication equipment such as a switchboard is connected to a rectifier 1-a for converting an input AC into a DC, and is connected in parallel to an output of the rectifier 1-a to perform full-floating charging to perform power backup during an AC power failure. And a backup battery 1-b for performing the following. The station power supply 1 is distributed to the power supply system and the subscriber power supply system by the distribution fuses 2 and 3, and the power supply input terminals 4 and 6 of the power supply 28 and the power supply input terminal 7 for the subscriber are provided. , 8 respectively. The subscriber circuit 26 accommodates a plurality of subscribers, and a power supply circuit for the control circuit and a power supply circuit for the subscriber communication path are connected to power supply output terminals 23a to 23n for the control circuit of the power supply 28 and the subscribers, respectively. And power supply output terminals 24 and 25.

The power supply 28 comprises a bias resistor 14, an electronic switch 16, and a switch 15, and a switch section connected between the power input terminal 4 and the power control terminal 5;
17, consisting of a switching power supply 19 that outputs a DC of a predetermined voltage under the control of the auxiliary power supply 17, receives the control of the switch unit, converts the DC input of the power input terminals 4 and 6 to a predetermined voltage, and outputs it to the power output terminals 23a to 23n. A switching power supply unit, a fuse 10, a relay 20, a relay contact 20-a, and a filter capacitor 22 for bypassing an AC component including pulse noise. And a power supply filter section that outputs to the power supply output terminals 24 and 25 without voltage conversion.

By turning on and off the switch 15, the respective outputs of the switching power supply unit and the power supply filter unit can be turned on and off simultaneously.

[Problems to be solved by the invention]

Since the above-described conventional power supply device does not include the voltage monitoring circuit of the power supply filter unit, no alarm is issued even when the distribution fuse 3 is blown or dropped, and the output of the switching power supply 19 is maintained. Met.
When the subscriber circuit 26 is composed of an IC, the potential of the communication path power supply supplied from the power supply filter unit becomes the base potential of the IC.
If the output of the IC continues to be supplied to the IC, the bias relationship in the IC collapses, causing a latch-up phenomenon and causing the power supply output terminals 23a to 23n
Large current will flow through For this reason, the output of the switching power supply 19 cannot maintain a normal value, and an alarm may be detected and stopped due to an overload, and in an extreme case, the subscriber circuit IC may be destroyed. Further, when the distribution fuse 3 is turned on again while the IC is in the latch-up state, energy is rapidly applied to the IC, so that a large power surge is generated in all the ICs to which the bias is supplied from the power supply filter unit, and a large number of ICs are generated. May be destroyed at the same time.

Further, when the office power supply 1 is stopped due to a long-term blackout of the AC power supply and the backup battery 1-b continues to be discharged, a drop in the input voltage cannot be detected, and the battery may be in an overdischarged state.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a power supply apparatus for supplying an output obtained by performing voltage conversion of an input power supply (supplied from a local power supply) and an output not subjected to voltage conversion to the same load, thereby promptly detecting abnormal voltage of the input power supply. An object of the present invention is to provide a power supply device that detects and reports a voltage and that prevents a load from being destroyed due to a voltage abnormality of an output that does not perform voltage conversion.

[Means for solving the problem]

The power supply device of the present invention receives power from a central office power supply that converts alternating current into direct current and performs backup while using a battery, and supplies power to a load that requires first and second input DC power supplies having different voltages. In the power supply device, a voltage conversion unit that receives power from the office power supply, converts the power into a DC of a predetermined voltage, and supplies the DC as the first DC input power to the load, and an AC component that receives power from the office power supply. And a filter unit for supplying the load as the second DC input power to the load without converting only the DC component as a voltage, and simultaneously turning on or off a DC supply output of each of the voltage conversion unit and the filter unit. A switch means for monitoring a voltage of the DC supply output of the filter means, and detecting that this voltage deviates from a preset allowable voltage range. Then, a voltage monitoring means for controlling the switch means to simultaneously turn off the DC supply output of each of the voltage conversion means and the filter means and for sending a voltage abnormality alarm to the outside is provided.

〔Example〕

 Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention.
The power supply device 27 of this embodiment comprises a fuse 9, an auxiliary power supply 17, and a switching power supply 19, receives power from the office power supply 1 through the distribution fuse 2 to the power supply input terminals 4, 6, and converts the power to a predetermined voltage DC. Switching power supply unit that outputs to the power output terminals 23a to 23n, a fuse 10, a relay 20, a relay contact 20-a,
Power is supplied from the office power supply 1 through the distribution fuse 3 to the power supply input terminals 7 and 8 and comprises a filter capacitor 22 to remove the AC component and convert the DC component only to the power output terminals 24 and 25 without voltage conversion. A power supply filter section, which comprises a bias resistor 14, an electronic switch 16, and a switch 15, and an auxiliary power supply 17 and a relay 20 when the switch 15 is turned on and off.
And a switch section for controlling the outputs of the switching power supply section and the power supply filter section to be simultaneously turned on and off, and a voltage monitoring circuit 21, a photocoupler 18, a bias resistor 11, a relay 12,
It monitors the voltage between the power supply output terminals 24 and 25 of the power supply filter section comprising a relay contact 12-a and a transistor 13, and detects that the voltage has deviated from a preset allowable voltage range. It comprises a bias monitor 14 and a voltage monitoring unit for disconnecting the power control terminal 5.

Further, the voltage monitoring unit includes a relay contact 12-b of the relay 12, and detects that the voltage between the power output terminals 24 and 25 is out of the allowable voltage range, and outputs the alarm output terminals 12-c and 12-b.
Send an alarm externally via -d.

The configurations and functions of the office power supply 1 and the subscriber circuit 26 are the same as those in the related art. That is, the office power supply 1 includes a rectifier 1-a for converting an input AC into a DC, and a backup battery 1 connected in parallel to an output of the rectifier 1-a to perform charging by a full-floating method and perform power backup in the event of an AC power failure. -B. Further, the power supply terminals 1 to 8 and the power supply output terminals 23a to 23a of the station power supply 1 and the subscriber circuit 26 and the power supply device 27.
Connections with 3n, 24, and 25 are also the same as before.

 Next, the operation will be described.

Now, when the switch 15 is on, the output of the switching power supply 19 is output to the power output terminals 23a to 23n, and the power input terminal
It is assumed that the inputs 7, 8 are output to the power output terminals 24, 25. At this time, if the distribution fuse 3 is blown or dropped, the output of the power supply output terminals 24 and 25 is
The voltage gradually drops due to When this output voltage reaches the lower limit set voltage of the voltage monitoring circuit 21, the voltage monitoring circuit 21
Turns off the relay 12 via the photocoupler 18 and the transistor 13, and turns off the electronic switch 16 via the relay contact 12-a of the relay 12. Therefore, the switching power supply 19
Is stopped, and the power supply for the control circuit is stopped when the voltage of the power supply for the subscriber communication path of the subscriber circuit 26 is still left, so that the latch-up of the IC is prevented beforehand and the destruction is avoided. .

Similarly, even if the voltage of the station power supply 1 rises and exceeds the upper limit set voltage of the voltage monitoring circuit 21, the switching power supply 19 also stops, and the output of the power supply filter section also stops by the relay contact 20-a of the relay 20. Therefore, it is possible to prevent the subscriber circuit 26 and the power supply device 27 from being destroyed.

When the voltage monitoring circuit 21 turns off the relay 12, the relay contact 12-b is also turned off and the alarm output terminals 12-c, 12-
Send an abnormal voltage alarm to the outside via -d.

〔The invention's effect〕

As described above, the present invention provides an input power supply, that is, an output voltage of a filter means which receives a power supply from a station power supply having a backup battery and generating a direct current and directly supplying the direct current component to the load without voltage conversion. When voltage abnormality is detected, the output of the filter means and the output of the voltage conversion means for converting the voltage supplied from the local power supply and supplying the same load to the same load are simultaneously turned off, and the voltage abnormality is detected. Since an alarm is sent out, it is possible to detect both an abnormality in the input voltage of the input power supply for the station power supply voltage side and an abnormality in the output voltage of the office power supply, preventing damage to the load due to an abnormality in the input power supply voltage. In addition to this, it is possible to predict the overdischarge of the backup battery in the event of a long-term power failure of the AC power supply, which is the DC power source of the office power supply.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a block diagram showing an example of a conventional power supply device. 1 Power supply for office, 1-b Backup battery, 2, 3 Distribution fuse, 9, 10 Fuse, 11, 14
… Bias resistor, 12,20 …… Relay, 12−a, 12−b, 20−
a relay contact, 13 transistor, 15 switch, 16 electronic switch, 17 auxiliary power supply, 18 photocoupler, 19 switching power supply, 21 voltage monitoring circuit, 22 filter Capacitor, 26 …… Subscriber circuit, 2
7,28 ... Power supply.

Claims (1)

(57) [Claims] 1. A power supply device for receiving power from an office power supply which converts an alternating current to a direct current and outputs it while backing up by a battery, and for supplying a load requiring first and second input DC power supplies having different voltages. A voltage conversion unit that receives power from the office power supply, converts the power into a DC voltage having a predetermined voltage, and supplies the DC power as the first DC input power to the load; and removes an AC component from the power supply from the office power supply. Filter means for supplying only the DC component to the load as the second DC input power without converting the voltage, and switch means for simultaneously turning on or off the DC supply output of each of the voltage conversion means and the filter means And monitoring the voltage of the DC supply output of the filter means and detecting that this voltage has deviated from a preset allowable voltage range, A power supply apparatus comprising: a voltage monitoring unit that controls the switch unit to simultaneously turn off the DC supply outputs of the voltage conversion unit and the filter unit, and that sends a voltage abnormality alarm to the outside.