JPH028538B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an AC duplex power supply device with improved safety.

BACKGROUND ART Conventionally, electronic/electrical devices that operate on AC power are generally supplied with power from one power system. Therefore, if a failure or the like occurs in the power system and the power supply is stopped, all of the equipment will lose its functionality. Therefore,
BACKGROUND ART Recently, for very important electronic/electrical equipment, the electronic/electrical equipment is made redundant, and a redundant power supply device is being used so that the electronic/electrical equipment receives power from different power systems.

However, if a failure occurs in the circuit that switches the power receiving system and the two systems are interrupted, or if a short circuit occurs on the load side, it may cause fire or burnout.

This invention has been made based on the above-mentioned circumstances, and it is an object of the present invention to provide a highly safe AC duplex power supply device that will not cause a fire or burnout even if a failure or accident occurs.

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

FIG. 1 is a block diagram showing the configuration of the AC duplex power supply device in this embodiment. Note that this device has a two-system configuration, an A system and a B system. Therefore, in the following description, the symbols A and B indicate that they are of the A system and B system, respectively. Moreover, the thick line indicates an AC line.

In Figure 1, 1A and 1B are separate systems that are independent of each other, for example, AC power supplies with separate power receiving and substation systems;
A and 2B are AC power receiving terminal blocks that input the output of AC power supplies 1A and 1B, and 3A and 3B are AC power receiving terminal blocks 2.
This is a wiring disconnector with an external trip terminal connected to A and 2B. These disconnectors 3A and 3B are configured to trip when a trip command is input to an external trip terminal. Further, 4A and 4B are line filters, and 5A and 5B are control power supply devices. This control power supply device includes a line filter 4A,
It converts the alternating current output from 4B into direct current, and its circuit configuration will be described later. 6A and 6B are power supplies
The OR diode 7 is a monitoring control device.
This monitoring and control device 7 monitors whether or not power is being supplied to the A system, and also controls semiconductor switches such as solid state relays (hereinafter referred to as SS relays) 8A, 8B and 9A, 9B. , the circuit configuration will be described later. Above SS
Relays 8A, 8B and 9A, 9B become conductive when a gate signal is applied from supervisory control device 7, and output alternating current applied from line filters 4A, 4B. 10A is a resistor, and 11 is a protective wiring line and disconnector connected between the output terminals of SS relays 8A, 9A and 8B, 9B to connect both systems A and B. When this cable disconnector 11 is opened, the wiring cable disconnector 3A, 3B with the external trip terminal
It is now possible to give a trip command to Further, 12A and 12B are output terminals connected to line filters 4A and 4B of both systems A and B, and for example, a rectifier with a DC output voltage of 5V is connected to each,
DC power is supplied to the load by using the DC outputs of both rectifiers through an OR circuit. 13A and 13B are SS relays 8A, 9A and
In addition to being connected to SS relays 8B and 9B, SS relays 8B and 9B of other systems are connected via protective wiring and disconnectors.
This is a common output terminal connected to 9B and SS relays 8A and 9A. These common terminals 13A, 13
B is connected to, for example, a cooling fan that is commonly used for devices connected to the output terminals 12A and 12B. Also, when only the AC system is duplicated, devices can be connected to this common terminal.

The control power supply devices 5A, 5B and the supervisory control device 7 are constructed as shown in FIG. That is, the control power supply device 5A has the line filter 4
The primary side of a step-down transformer 51A is connected to the output side of A, the input side of a rectifier circuit 52A is connected to this secondary side, and a resistor 53A is connected to the output side of this rectifier circuit 52A.
Diode 54A, electrolytic capacitor 55A, capacitor 56A, regulator 57A, resistor 58
A and a capacitor 59A are connected as shown in the figure. In addition, the control power supply device 5B connects the primary side of a step-down transformer 51B to the output side of the line filter 4B, connects a rectifier circuit 52B to the secondary side, and connects an electrolytic capacitor 55B and a capacitor 56B to the output side of the rectifier circuit 52B. , regulator 57
B, a resistor 58B, and a capacitor 59B are connected as shown in the figure.

On the other hand, the supervisory control device 7 includes a detection circuit 7L and a switching circuit 7R. The above detection circuit 7L
is to input the DC output of the rectifier circuit 52A of the control power supply device 5A and detect whether or not power is being supplied to the A system from the AC power supply 1A. This detection circuit 7L includes an electrolytic capacitor 71, a Zener diode 72, resistors 73 and 74, diodes 75 and 76, resistors 77 and 78, and an NPN
It is configured as shown in the figure by type transistor Q, resistor 79, and inverter J. When power is supplied to system A, transistor Q is turned on, this transistor Q becomes low level, and inverter J
output is now at a high level. In addition, the switching circuit 7R includes relays K1 and K2,
NPN transistors Q1 and Q2, an oscillator and a timing circuit S, in particular the normally open contact K1a of the relay K1 and the collector of the transistor Q1 are connected in series, and the normally open contact K of the relay K2 is connected in series.
2a and the collector of transistor Q2 are connected in series, and the SS relays 8A and 9A are made conductive depending on whether power is supplied to the A system or not.
This is used to conduct or switch SS relays 8B and 9B, and when the output of inverter J is high level,
After relay K1 operates and its contact K1a closes, transistor Q1 turns on and SS relay 8A,
When 9A is made conductive and the collector of transistor Q is at a high level, relay K2 is operated and its contact K2a is closed, and then transistor Q2 is turned on and SS relays 8B and 9B are made conductive. At this time, when switching conduction between SS relays 8A, 9A and SS relays 8B, 9B, the system is switched to the live system after a certain period of time (approximately 10 ms) has elapsed. This prevents the alternating current of both systems from shorting within half a cycle of AC when the phases of the AC inputs of the A system and B system are different, for example, when the A system is 50 Hz and the B system is 60 Hz. It's for a reason. Normally, this switching time is within the DC holding time (instantaneous power failure time) of the DC power source of the device, so there is no problem.

Next, the operation of the above configuration will be explained.

Now, the wire breakers 3A, 3B and 1 shown in Fig.
1 is turned on, AC power supply 1A, 1
The AC output of B is the AC power receiving terminal block 2A and 2.
B, line breaker 3A and 3B, line filter 4
A and 4B to output terminals 12A and 1
2B, control power supplies 5A and 5B, SS relays 8A and 8B, and SS relays 9A and 9B.

Thereby, the alternating current applied to the output terminals 12A and 12B is applied to the electronic/electrical equipment connected to each of them. In addition, control power supply devices 5A, 5
The alternating current applied to B is converted to direct current, and as shown in FIG.
The final output of 5B is given to a switching circuit 7R via diodes 6A and 6B.

In this situation, power is still being supplied to both systems A and B from power supplies 1A and 1B, or power is being supplied to both systems A and B.
When power is not supplied to the grid from the power source 1B, as shown in FIG. Given.

Therefore, the detection circuit 7L operates and the transistor Q is turned on. As a result, the collector of transistor Q becomes low level, and the output of inverter J becomes high level. Therefore, relay K1 operates and contact K1a is closed, and then transistor Q1 is turned on and SS relays 8A and 9A are made conductive. Therefore, the power of A system is SS relay 8A,
9A to the common output terminal 13A, and the common output terminal 13B via the shield breaker 11.
It is also given to Therefore, the common output terminal 13
For example, a cooling fan connected to A and 13B rotates.

On the other hand, if power is no longer supplied to the A system, there will be no intermediate output or final output from the controlled power supply device 5A. However, since power is supplied to the B system, DC power is supplied to the supervisory control device 7 from the control power supply device 5B via the diode 5B. As mentioned above, when the output of the control power supply device 5A disappears midway, the transistor Q of the detection circuit 7L
is turned off. As a result, the collector of transistor Q becomes high level, and the output of inverter J becomes low level. Therefore, for a certain period of time (approximately
10ms), transistor Q1 and relay K1 turn off, and after about 10ms, relay K2 and transistor Q2 turn on, SS relays 8B and 9B conduct, and power from system B is transferred to output terminal 13B. It is also applied to the output terminal 13A via the breaker 11. Thereby, even if power is no longer supplied from the A system, power is continuously supplied from the B system to the common output terminals 13A and 13B.

In this way, if power is supplied to at least one of the A and B systems, the common output terminal 13
Power is supplied to A and 13B from the power system, but if power is lost to both systems or a short circuit occurs on the common load side, the protective wiring will be disconnected. The circuit 11 is opened.
Therefore, Konoshiya disconnector 11 Mustard disconnector 3
A trip command is given to circuit breakers A and 3B, and these shield circuit breakers 3A and 3B are tripped to protect the equipment.

As described above, according to this embodiment, a common load, such as a cooling fan whose operation is not desirable, is connected to each power system so that it can be used commonly for the loads that are directly connected to each power system. If a failure or accident occurs in such an important common load, in order to prevent the impact from spreading to the load of each power system, immediately open the protective circuit and disconnect the circuit, and disconnect the power from each power system. A trip command is given to the Noshiya disconnector, making it possible to cut off the power supply from all power systems. Therefore, a highly safe device is obtained in which abnormal current does not continue to flow and does not cause fire or burnout.

Note that this invention is not limited to the above embodiments. For example, in the embodiment described above, a solid state relay is used as the semiconductor switch, but a thyristor or the like may also be used. others,
Of course, various modifications can be made without departing from the gist of the invention.

As explained above, according to the present invention, the power supply side terminals are connected to the first and second power systems that are independent of each other, and the loads are connected to the output sides of the power systems, respectively, and the circuit is opened when a trip command is given. A first and a second breaker are provided, and the first
and first and second semiconductor switches are provided on the output side of the second insulation breaker, which become conductive when a gate signal is applied to each output side, and a common load commonly used for the above-mentioned loads is connected to the output side of the switch. , an open circuit occurs between the output terminals of the first and second semiconductor switches due to an abnormality in the common load, and a protective shield disconnector is provided which outputs a trip command to the first and second disconnectors due to this open circuit. furthermore, the above first
and obtains operating power from a second power system and monitors whether or not power is being supplied to the first semiconductor switch from the first power system, and the power is being supplied from the first power system. A monitoring and control device is provided which provides a gate signal to the first semiconductor switch when power is not being supplied from the first power system and a gate signal to the second semiconductor switch when power is not supplied from the first power system. When a failure or accident occurs in a load, the protective circuit is immediately opened, and at the same time a trip command is given to the first and second circuit disconnectors, allowing them to quickly cut off the power supply from all power systems. Therefore, it is possible to provide a highly safe AC duplex power supply device that will not cause fire or burnout even if a failure or accident occurs in the common load.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the AC duplex power supply device of the present invention, and FIG. 2 is a circuit diagram of the control power supply device and supervisory control device of FIG. 1. 1A, 1B...AC power supply, 3A, 3B...Wiring cutter with external trip terminal, 5A, 5B...Control power supply device, 7...Monitoring control device, 7L...Detection circuit, 7R...Switching circuit , 8A, 8B, 9A, 9
B...SS relay, 11...Protective wiring and disconnector,
12A, 12B...Output terminal, 13A, 13B...
...Common output terminal.

Claims (1)

[Claims] 1. First and second power circuit breakers, each having a power supply side terminal connected to a first and second electric power system independent of each other, a load connected to each output side thereof, and opening when a trip command is given. , the first and second circuit breakers are connected to the output sides of the first and second circuit breakers, respectively, and become conductive when a gate signal is applied, to the output sides of which a common load commonly used for the above-mentioned loads is respectively connected. It is connected between the second semiconductor switch and the output terminals of the first and second semiconductor switches, and is opened due to an abnormality in the common load, and this open circuit outputs a trip command to the first and second disconnectors. and a protective disconnector that obtains operating power from the first and second power systems and monitors whether or not power is being supplied to the first semiconductor switch from the first power system. When power is being supplied from the first power system, a gate signal is given to the first semiconductor switch; when power is not being supplied from the first power system, a gate signal is given to the second semiconductor switch. An AC duplex power supply device characterized by comprising a monitoring control device.