JP7311462B2 - Power supply switching device, emergency power supply system, and power supply switching method - Google Patents

Description

The present invention relates to a power switching device, an emergency power system, and a power switching method.

2. Description of the Related Art Various electrical equipment supporting social infrastructure, such as wireless communication equipment arranged in base stations of mobile phone systems, are installed in areas where access is not easy, such as mountains. Electrical installations are normally supplied with power from power plants via transmission and distribution lines. In order to maintain the power supply to electrical equipment when the supply of electricity to electrical equipment is stopped due to a natural disaster such as a typhoon or an earthquake that cuts off distribution lines, etc. An emergency power generation facility and an uninterruptible power supply are arranged (see Patent Document 1, for example). However, installing emergency power generation equipment and uninterruptible power supply equipment increases installation costs and maintenance and inspection costs, so emergency power generation equipment and uninterruptible power supply equipment are not installed in all electrical equipment.

Electrical equipment that does not have an emergency generator or an uninterruptible power supply maintains its function by transporting a generator and supplying power from the transported generator when the power supply is stopped due to a power failure. do. By transporting a large capacity generator on a vehicle such as a loaded truck crane, the electrical equipment can be powered by the generator for a relatively long period of time.

On the other hand, it is not easy to bring in a large-capacity generator for electrical equipment installed in areas where it is not easy to access by vehicle, such as in the mountains. Power is supplied by

JP-A-5-207684

However, when electric power is supplied to electrical equipment by portable generators, workers frequently visit electrical equipment that is not easily accessible to refuel the generators with fuel such as gasoline and light oil, resulting in maintenance problems. Costs may rise.

SUMMARY OF THE INVENTION An object of the present invention is to provide a technology capable of reducing maintenance costs when power is supplied from a portable generator to electrical equipment that is not easily accessible.

A power switching device according to the present invention includes a first terminal supplied with power from a first power supply, a second terminal supplied with power from a portable second power supply different from the first power supply, a first terminal and A third terminal that supplies power supplied through either one of the second terminals to the load, a power failure detection element that detects that the first voltage applied to the first terminal has decreased, and a first voltage It has a switching control circuit for activating the second power supply when a drop is detected, and a controlled power supply for supplying power to the switching control circuit.

Furthermore, in the power supply switching device according to the present invention, it is preferable that the power failure detection element electrically connects the switching control circuit and the control power supply when detecting a drop in the first voltage.

Further, in the power switching device according to the present invention, the switching control circuit disconnects the first power supply and the load and connects the second power supply and the load when a drop in the first voltage is detected. It is preferable to have a switching switch that

Further, in the power supply switching device according to the present invention, the second power supply is started in response to input of a start instruction indicating that the second power supply is to be started, and the switching control circuit is started while electric power is being supplied from the control power supply. a start instruction element for outputting an instruction to the second power supply, and after a predetermined first count time has elapsed since the drop in the first voltage was detected, stopping the supply of power from the control power supply to the start instruction element, It is preferable to further have a first timer for stopping the output of the start instruction.

Further, in the power supply switching device according to the present invention, the second power supply continues to operate while the operation instruction indicating to continue operation is input, and the switching control circuit continues to operate while power is supplied from the control power supply. a first operation instruction element for outputting an operation instruction to a second power supply; a second operation instruction element for outputting an operation instruction to the second power supply while power is being supplied from the second power supply; and power from the second power supply. After a predetermined second count time elapses after the start of supply, the electrical connection between the control power supply and the first drive instruction element is cut off to stop the output of the drive instruction from the first drive instruction element. It is preferable to further have a second timer that

Further, in the power switching device according to the present invention, the switching control circuit cuts off the supply of electric power from the second power supply to the second operation instruction element in response to being pressed, thereby causing the second operation instruction element to It is preferable to further include an operation stop switch for stopping the output of the operation instruction to the second power supply to stop the operation of the second power supply.

Furthermore, in the power switching device according to the present invention, the first power source and the second power source are preferably portable generators.

Further, the emergency power supply system according to the present invention includes a first power supply, a portable second power supply different from the first power supply, and a load to which power is supplied from either the first power supply or the second power supply. a power source switching device for switching a power source for supplying power to the load from the first power source to the second power source, wherein the power source switching device includes a first terminal to which power is supplied from the first power source; A second terminal to which power is supplied, a third terminal to supply power to a load, a power failure detection element that detects a drop in the first voltage applied to the first terminal, and a drop in the first voltage is detected. a switching control circuit for activating the second power supply when the second power supply is turned on; and a control power supply for supplying power to the switching control circuit.

Further, the power source switching method according to the present invention detects that the power supply from the first power source to the load has stopped, starts a portable second power source different from the first power source, and supplies power to the load. Switching the power source from the first power source to the second power source.

ADVANTAGE OF THE INVENTION The power supply switching apparatus which concerns on this invention can hold down maintenance cost, when supplying electric power with a portable generator to the electrical equipment with which access is not easy.

1 is a diagram showing an emergency power supply system having a power switching device according to an embodiment; FIG. 2 is a block diagram of the emergency power supply system shown in FIG. 1; FIG. FIG. 2 is a front view of the power switching device shown in FIG. 1; 4 is a sequence diagram of a power failure detection element and a switching control circuit shown in FIG. 3; FIG. FIG. 10 is a sequence diagram (part 1) showing power switching processing; FIG. 12 is a sequence diagram (part 2) showing power switching processing; FIG. 11 is a sequence diagram (part 3) showing power switching processing; FIG. 12 is a sequence diagram (part 4) showing power switching processing; FIG. 12 is a sequence diagram (No. 5) showing power switching processing; FIG. 16 is a sequence diagram (part 6) showing power switching processing;

DETAILED DESCRIPTION OF THE INVENTION A power supply switching device, an emergency power supply system, and a power supply switching method according to the present invention will be described in detail below with reference to the accompanying drawings. However, it should be noted that the technical scope of the present invention is not limited to those embodiments, but extends to the invention described in the claims and equivalents thereof.

(Summary of emergency power supply system and power supply switching device according to embodiment)
FIG. 1 is a diagram showing an emergency power supply system according to an embodiment.

The emergency power supply system 100 has a first power supply 101 , a second power supply 102 , a load 103 and a power switching device 1 . The first power source 101 and the second power source 102 are, for example, portable generators having gasoline engines that use gasoline as fuel, and generate three-phase 200V AC voltage. The load 103 is, for example, wireless communication equipment located at a base station of a mobile phone system.

In response to detecting that the remaining amount of gasoline in the first power supply 101 has become zero and the power supply from the first power supply 101 to the load 103 has been stopped, the power supply switching device 1 switches between the load 103 and the power supply. The connection is switched from the first power supply 101 to the second power supply 102 . The power switching device 1 also switches the electrical connection with the load 103 from the first power supply 101 to the second power supply 102 and starts the second power supply 102 .

In the emergency power supply system 100, when the power supply from the first power supply 101 is stopped, the electrical connection with the load 103 is switched to the second power supply 102 and the second power supply 102 is started. , the power supply to the load 103 is started. In the emergency power supply system 100, when the remaining amount of gasoline in the first power supply 101 becomes zero and the power supply from the first power supply 101 stops, the second power supply 102 is started to supply power from the second power supply 102. The power supply is started and the power supply to the load 103 is continued.

In the emergency power supply system 100, the power supply switching device 1 switches the power supply of the load 103 from the first power supply 101 to the second power supply 102, so that the frequency of gasoline replenishment is half that when power is supplied to the load from a single power supply. As a result, maintenance costs can be reduced.

(Structure and function of emergency power supply system and power supply switching device according to embodiment)
FIG. 2 is a block diagram of the emergency power supply system 100, and FIG. 3 is a front view of the power switching device 1. As shown in FIG.

The first power source 101 is a portable motor-generator having a gasoline engine that uses gasoline as fuel. The first power supply 101 is started by an operator's starting operation, generates a three-phase 200V AC voltage, and supplies the generated three-phase 200V AC voltage to the load 103 via the power switching device 1 .

The second power supply 102 is a portable engine generator having a gasoline engine that uses gasoline as fuel, and has a starting circuit 121 and an operating circuit 122 . The starting circuit 121 performs a starting process for starting the second power supply 102 in response to input of a starting instruction from the power switching device 1 . The operation circuit 122 executes operation processing for continuing the operation of the second power source 102 while the operation instruction is input from the power switching device 1 .

The load 103 is, for example, wireless communication equipment arranged in a base station of a mobile phone system, and performs a predetermined operation with power supplied from either the first power supply 101 or the second power supply 102 .

The power switching device 1 has a first terminal 11, a second terminal 12, a third terminal 13, a power failure detection element 14, a switching control circuit 15, a control power supply 16, and a DC connector 17. It is stored in a highly waterproof box such as a distribution board. Each of the first terminal 11, the second terminal 12, and the third terminal 13 is a terminal for inputting and outputting three-phase electric power of a first phase R, a second phase S, and a third phase T, each of which has a phase difference of 120 degrees. It is a table. Power is supplied to the first terminal 11 from the first power supply 101 , and power is supplied to the second terminal 12 from the second power supply 102 . The third terminal 13 supplies the load 103 with power supplied through either one of the first terminal 11 and the second terminal 12 .

The power failure detection element 14 is an electromagnetic relay, also called a relay, having an excitation coil and a normally closed contact that opens when the excitation coil is energized and closes when the excitation coil is not energized. It is a voltage detection element. The excitation coil of the power failure detection element 14 is connected to the first phase R and the second phase S of the first terminal 11 and is applied with the first voltage V1 when power is supplied from the first power supply 101 . The excitation coil of the power failure detection element 14 may be connected to any two phases of the first phase R, the second phase S and the third phase T.

The switching control circuit 15 switches connection to the load 103 from the first power supply 101 to the second power supply 102 when the power failure detection element 14 detects that the power supply from the first power supply 101 has stopped, and switches the connection to the load 103 from the first power supply 101 to the second power supply 102. Start the power supply 102 .

The control power supply 16 is, for example, a power supply device having eight AA alkaline batteries each having a voltage of 1.5 V and a housing containing wiring for connecting the eight alkaline batteries in series. The control power supply 16 supplies a DC voltage of 12V to the switching control circuit 15 as a control voltage Vc.

The DC connector 17 detachably connects the switching control circuit 15 and the control power supply 16 . Since the control power supply 16 is detachably connected to the switching control circuit 15 via the DC connector 17, the control power supply 16 can be easily replaced.

The switching control circuit 15 includes a first relay 21, a second relay 22, a third relay 23, a first timer 24, a second timer 25, an operation stop switch 26, an energization display lamp 27, and a DC terminal. It has a base 28 , a control power switch 29 and a switching switch 30 . The first relay 21 is labeled "R1", the second relay 22 is labeled "R2", the third relay 23 is labeled "R3", and the first timer 24 is labeled "T1". and the second timer 25 is labeled "T2".

The first relay 21, the second relay 22, and the third relay 23, like the power failure detection element 14, are electromagnetic relays also called relays. The first relay 21 and the second relay 22 are connected to the control power supply 16 and supplied with the control power supply Vc as a driving voltage. The third relay 23 is connected to the first phase R and the second phase S of the second terminal 12, and is supplied with the second voltage V2 as a drive voltage.

The first timer 24 and the second timer 25 are digital or analog timer relays, and have normally-open contacts that open after a predetermined time has elapsed since the excitation coil started to be energized. be. The normally open contact of the first timer 24 opens after the lapse of the first count time from the start of energization of the excitation coil, and the normally open contact of the second timer 25 opens the second count time after the start of energization of the excitation coil. Open after The first timer 24 is supplied with the control voltage Vc from the control power supply 16 as a drive voltage, and the second timer 25 is supplied with the second voltage V2 from the second terminal 12 as a drive voltage.

The operation stop switch 26 is a push button switch, and stops the second power supply 102 when pressed after the control power switch 29 is turned off. The energization indicator lamp 27 is connected to the first phase R and the second phase S of the third terminal 13, lights while power is supplied to the load 103 through the third terminal, and is not supplied to the load 103. lights out in between. The DC terminal block 28 is a terminal block that connects each of the first relay 21 to the energization indicator lamp 27 and the control power supply 16 . The control power switch 29 is a snap switch with one end connected to the control power supply 16 and the other end connected to the switching control circuit 15 , and turns power supply from the control power supply 16 to the switching control circuit 15 on and off.

The switching switch 30 is an automatic power switching switch having a terminal section 31 and a control section 32, and having a rated voltage of 200V and a rated current of 60A. The switching switch 30 connects the first terminal 11 and the third terminal 13 when power is supplied from the first power supply 101 through the first terminal 11 . Further, the switching switch 30 connects the first terminal 11 and the third terminal 13 when power is not supplied from the first power supply 101 and power is supplied from the second power supply 102 via the second terminal 12. do.

The terminal portion 31 is connected to the first terminal 11 via the first wiring 41 to the third wiring 43, is connected to the second terminal 12 via the fourth wiring 44 to the sixth wiring 46, and is connected to the seventh wiring 47 to the second terminal 12 via the fourth wiring 44 to the sixth wiring 46. It is connected to the third terminal 13 via the ninth wiring 49 . The control unit 32 is supplied with the first voltage V1 through the first terminal 11 and is supplied with the second voltage V2 through the second terminal 12 . The control unit 32 electrically connects the first power supply 101 and the load 103 when the first voltage V1 is supplied, and electrically connects the first power supply 101 and the load 103 when the first voltage V1 is not supplied and the second voltage V2 is supplied. 2 The terminal section 31 is controlled so as to electrically connect the power source 102 and the load 103 .

FIG. 4 is a sequence diagram of the power failure detection element 14 and the switching control circuit 15. As shown in FIG.

The first voltage V1 is applied to the excitation coil 140 of the power failure detection element 14 from the first power supply 101, and the second voltage V2 is applied from the second power supply 102 to the excitation coil 230 of the third relay 23 and the excitation coil 250 of the second timer 25. applied. A control voltage Vc is applied from the control power supply 16 to the excitation coil 210 of the first relay 21 , the excitation coil 220 of the second relay 22 and the excitation coil 240 of the first timer 24 .

The normally closed contact 142 of the power failure detection element 14 includes the exciting coil 210 of the first relay 21, the exciting coil 220 of the second relay 22, the exciting coil 240 of the first timer 24, the normally closed contact 242 of the first timer 24 and the second It is connected in series with the normally closed contact 252 of the 2 timer 25 . The excitation coil 210 of the first relay 21 is energized when the normally closed contact 142 of the power failure detection element 14, the normally closed contact 242 of the first timer 24, and the normally closed contact 252 of the second timer 25 are closed. The excitation coil 220 of the second relay 22 and the excitation coil 240 of the first timer 24 are energized when the normally closed contact 142 of the power failure detection element 14 and the normally closed contact 252 of the second timer 25 are closed.

The normally open contact 211 of the first relay 21 is connected in series with the starting circuit 121 of the second power supply 102 . When the excitation coil 210 of the first relay 21 is energized and the normally open contact 211 is closed, a starting instruction is input to the starting circuit 121 . Starting circuit 121 starts second power supply 102 in response to input of a starting instruction.

The normally open contact 221 of the second relay 22 and the normally open contact 231 of the third relay 23 are connected in series to the operating circuit 122 of the second power supply 102 . When at least one of the excitation coil 220 of the second relay 22 and the excitation coil 230 of the third relay 23 is energized and either the normally open contact 221 or the normally open contact 231 is closed, an operation instruction is input to the operation circuit 122. . While the operation instruction is input to the operation circuit 122, the second power supply 102 continues to operate.

A normally closed contact 222 of the second relay 22 is connected in series with the excitation coil 140 of the power failure detection element 14 . When the exciting coil 220 of the second relay 22 is energized and the normally closed contact 222 opens, the connection between the exciting coil 140 connected in series with the normally closed contact 222 and the first power supply 101 is cut off. While the normally closed contact 222 of the second relay 22 is open, the connection between the excitation coil 140 and the first power supply 101 is cut off. There is no risk of chattering of the normally closed contact 142 in response to fluctuations in the 1 voltage V1.

A normally closed contact 242 of the first timer 24 is connected in series with the exciting coil 210 of the first relay 21 . A normally closed contact 242 is opened after a predetermined first count time has elapsed since the excitation coil 240 of the first timer 24 was started to be energized. The first count time is, for example, 4 seconds. When the normally closed contact 242 opens, the electrical connection between the control power supply 16 and the exciting coil 210 of the first relay 21 is cut off, and the energization of the exciting coil 210 of the first relay 21 stops.

The normally closed contact 252 of the second timer 25 is connected in series with the exciting coil 210 of the first relay 21 , the exciting coil 220 of the second relay 22 and the exciting coil 240 of the first timer 24 . The normally closed contact 252 is opened after a predetermined second count time has passed since the excitation coil 250 of the second timer 25 started to be energized. The second count time is, for example, 12 seconds. When the normally closed contact 252 opens, the electrical connection between the control power source 16 and the exciting coils 210, 220 and 240 is interrupted, and the exciting coils 210, 220 and 240 are energized. Stop.

The stop switch 26 is connected in series with the exciting coil 230 of the third relay 23 . When the operation stop switch 26 is pressed after the control power switch 29 is turned off, the energization of the excitation coil 230 of the third relay 23 is stopped and the normally open contact 231 of the third relay 23 is opened.

FIG. 5 is a sequence diagram (Part 1) showing the power switching process, FIG. 6 is a sequence diagram (Part 2) showing the power switching process, and FIG. 7 is a sequence diagram (Part 3) showing the power switching process. . 8 is a sequence diagram (part 4) showing the power supply switching process, FIG. 9 is a sequence diagram (part 5) showing the power supply switching process, and FIG. 10 is a sequence diagram (part 6) showing the power supply switching process. . 5 shows the first state, FIG. 6 shows the second state, FIG. 7 shows the third state, FIG. 8 shows the fourth state, FIG. 9 shows the fifth state, and FIG. 10 shows the sixth state. Indicates status. Each of FIGS. 5 to 10 is a sequence diagram of the power failure detection element 14 and the switching control circuit 15, similar to FIG.

In the first state, while power is supplied from the first power supply 101 to the load 103, current is supplied from the first power supply 101 to the excitation coil 140 of the power failure detection element 14, and the normally closed contact 142 of the power failure detection element 14 is opened. , the electrical connection between the switching control circuit 15 and the control power supply 16 is interrupted. While power is being supplied from the first power supply 101 to the load 103, the normally closed contact 142 of the power failure detection element 14 is opened, and the electrical connection between the switching control circuit 15 and the control power supply 16 is cut off. The power charged in the power supply 16 is not consumed.

In the second state, the first voltage V1 supplied from the first power supply 101 to the load 103 is lowered, the energization of the excitation coil 140 of the power failure detection element 14 is stopped, and the normally closed contact 142 of the power failure detection element 14 is closed. close. When the normally closed contact 142 of the power failure detection element 14 is closed, the excitation coil 210 of the first relay 21 is energized via the normally closed contact 242 of the first timer 24 and the normally closed contact 252 of the second timer 25 . Also, the exciting coil 220 of the second relay 22 and the exciting coil 240 of the first timer 24 are energized via the normally closed contact 252 of the second timer 25 .

When the excitation coil 210 of the first relay 21 is energized, the normally open contact 211 of the first relay 21 is closed and a start instruction is input to the starter circuit 121 of the second power supply 102 . Starting circuit 121 starts second power supply 102 in response to input of a starting instruction. Also, when the excitation coil 220 of the second relay 22 is energized, the normally open contact 221 of the second relay 22 is closed, and an operation instruction is input to the operation circuit 122 of the second power supply 102 . Also, when the exciting coil 240 of the first timer 24 is energized, the counting of the first timer 24 is started.

In the third state, when the time counted by the first timer 24 reaches the first count time, the normally closed contact 242 of the first timer 24 opens and the excitation coil 210 of the first relay 21 stops energizing. When the excitation coil 210 of the first relay 21 stops being energized, the normally open contact 211 of the first relay 21 opens, and the output of the starting instruction to the starting circuit 121 of the second power supply 102 ends.

In the fourth state, in response to the start of the second power supply 102, power supply from the second power supply 102 to the load 103 is started, and the exciting coil 230 of the third relay 23 and the exciting coil of the second timer 25 250 is energized. When the excitation coil 230 of the third relay 23 is energized, the normally open contact 231 of the third relay is closed, and the operation instruction to the operation circuit of the second power supply 102 is sent in parallel with the normally open contact 221 of the second relay 22. Output. Also, when the exciting coil 250 of the second timer 25 is energized, the counting of the second timer 25 is started.

In the fifth state, when the time counted by the second timer 25 reaches the second count time, the normally closed contact 252 of the second timer 25 opens to excite the exciting coil 220 of the second relay 22 and the second timer 25. The energization of the coil 250 is stopped. When the energization of the exciting coil 220 of the second relay 22 stops, the normally open contact 221 of the second relay 22 opens, and the output of the operation instruction to the operation circuit 122 of the second power supply 102 via the normally open contact 221 ends. . Since the operation instruction is output to the operation circuit 122 via the normally open contact 231 of the third relay 23, the operation of the second power supply 102 is continued.

In the sixth state, when the operator presses the operation stop switch 26 after the control power switch 29 is turned off, the energization of the excitation coil 230 of the third relay 23 is stopped. When the energization of the excitation coil 230 of the third relay 23 stops, the normally open contact 231 of the third relay 23 opens, and the output of the operation instruction to the operation circuit 122 of the second power supply 102 ends. The second power supply 102 stops generating power in response to the end of the output of the operation instruction to the operation circuit 122 of the second power supply 102 .

(Action and effect of the power switching device according to the embodiment)
The power source switching device 1 switches the power source from the first power source 101 to the second power source 102 to continue supplying power to the load 103 when the remaining amount of gasoline in the first power source 101 becomes zero. The power supply switching device 1 switches the power supply from the first power supply 101 to the second power supply 102 to continue supplying power to the load 103. Therefore, when the frequency of replenishing gasoline is to supply power to the load from a single power supply, can be halved, and maintenance costs can be reduced.

For example, if the first power source 101 and the second power source 102 can continuously generate power for 6 hours without replenishing gasoline, the emergency power system 100 can generate power for 12 hours without replenishing gasoline. It is possible to supply power to the load 103 over a period of time. Since the emergency power supply system 100 can supply power for 12 hours without refueling, it is possible to reduce the risk of operators performing work to replenish gasoline at night in areas where access is not easy, such as in the mountains.

In addition, the power supply switching device 1 can reduce the risk of handling gasoline, which is a dangerous substance, because the frequency of refueling with gasoline, which is a dangerous substance, is half that when power is supplied to the load from a single power source. .

Further, since the power switching device 1 has the switching switch 30 that switches the connection with the load 103 between the first power source 101 and the second power source 102, power is supplied from both the first power source 101 and the second power source 102. Simultaneous supply can be prevented.

In addition, in the power supply switching device 1, the electrical connection between the switching control circuit 15 and the control power supply 16 is cut off while the first power supply 101 is operating. The power charged in the power supply 16 is not consumed. The power switching device 1 does not consume the electric power charged in the controlled power source 16 while the first power source 101 is operating, so the life of the controlled power source 16 can be extended.

In addition, in the power supply switching device 1, after the second count time has passed since the second power supply 102 was started, the electrical connection between the switching control circuit 15 and the control power supply 16 is cut off. After the elapse of time, the power charged in the control power source 16 is not consumed. Since the power source switching device 1 does not consume the power charged in the control power source 16 after the second count time has passed, the life of the control power source 16 can be further extended.

In addition, the power source switching device 1 stops energizing the exciting coil 210 of the first relay 21 that outputs the start instruction after the first count time has elapsed since the second power source 102 started. Power consumption is reduced, and the life of the control power supply 16 can be further extended.

In addition, since the power switching device 1 uses the first power supply 101 and the second power supply in addition to the control power supply 16 as power supplies for controlling the switching control circuit 15, the power consumption of the control power supply 16 is reduced. 16 can be even longer.

In addition, in the power switching device 1, the first relay 21 to the second timer 25 for executing the starting process for starting the second power source 102 are inexpensive relays and timer relays. It is simple and can be manufactured at low cost.

In addition, since the power switching device 1 is housed in a highly waterproof case, there is little possibility that a short circuit due to flooding or the like will occur. Since the power switching device 1 is less likely to be short-circuited due to flooding or the like, it is less likely that the power switching device 1 fails and the power switching process from the first power source 101 to the second power source 102 is not executed.

(Modified example of the power switching device according to the embodiment)
In the power switching device 1, the control power source 16 has eight AA alkaline batteries. It may have alkaline batteries and may have primary batteries such as manganese batteries and lithium batteries. Moreover, in the power switching device according to the embodiment, the control power supply 16 may have a secondary battery such as a nickel-cadmium battery or a lithium-ion battery. Also, in the power switching device according to the embodiment, the control power supply 16 may have a button battery instead of the alkaline dry battery.

In the power switching device 1, the switching control circuit 15 has a relay and a relay timer, but in the power switching device according to the embodiment, the switching control circuit 15 has a programmable microcomputer instead of the relay and the relay timer. You may When the switching control circuit 15 has a microcomputer, the power switching process is executed in cooperation with an arithmetic circuit and a memory circuit of the microcomputer and a software program stored in the microcomputer.

The power switching device 1 is installed in a temporary distribution board, but the power switching device according to the embodiment receives power from a commercial power supply and supplies the received power to the load 103 inside the distribution board. may be placed in The power switching device 1 may be incorporated in a power supply circuit that supplies power to the load 103 when placed inside a switchboard. By incorporating the power supply switching device 1 into the power supply circuit, the first power supply 101 and the second power supply 102, which are portable generators, can be switched when a power failure of the commercial power supply that supplies power to the load 103 is assumed. By connecting to the device 1, it is possible to easily prepare for a commercial power failure.

In the emergency power supply system 100, the first power supply 101 and the second power supply 102 are portable generators having gasoline engines. However, in the emergency power supply system according to the embodiment, the first power supply 101 and the second power supply 102 may be portable generators having diesel engines that use light oil as fuel.

Moreover, in the emergency power supply system according to the embodiment, the first power supply 101 may be a commercial power supply. In the emergency power supply system according to the embodiment, by using the second power supply 102, which is a portable engine generator, as an emergency power supply when the first power supply 101, which is a commercial power supply, fails, the emergency power supply is inexpensive. can be realized by

In addition, in the emergency power supply system according to the embodiment, the power supply switching device 1 switches between the first power supply 101 and the second power supply 102, but in the emergency power supply system according to the embodiment, the power supply switching device 1 , may have a circuit configuration for switching between three or more power sources.

Reference Signs List 1 power switching device 11 first terminal 12 second terminal 13 third terminal 14 power failure detection element 15 switching control circuit 16 control power supply 17 DC connector 21 first relay (start instruction element)
22 second relay (first operation indicator element)
23 Third relay (second operation indicator element)
24 first timer 25 second timer 26 operation stop switch 100 emergency power supply system 101 first power supply 102 second power supply 103 load

Claims (8)

a first terminal to which power is supplied from a first power supply;
a second terminal to which electric power is supplied from a portable second power supply different from the first power supply;
a third terminal that supplies power supplied through one of the first terminal and the second terminal to a load;
a power failure detection element that has a contact that opens while a first voltage applied to the first terminal is applied and closes while the first voltage is not applied, and detects that the first voltage has decreased;
a switching control circuit that starts the second power supply when a drop in the first voltage is detected;
a control power supply that supplies power to the switching control circuit;
The power failure detection element cuts off electrical connection between the second power supply and the control power supply and the switching control circuit by opening the contact while power is supplied from the first power supply to the load. A power switching device characterized by: 2. The power switching device according to claim 1, wherein said power failure detection element electrically connects said switching control circuit and said controlled power supply when detecting a drop in said first voltage. The switching control circuit operates a switching switch that disconnects between the first power supply and the load and connects between the second power supply and the load when a drop in the first voltage is detected. 3. The power switching device according to claim 1, comprising: The second power supply starts in response to input of a start instruction indicating to start,
The switching control circuit is
a start instruction element that outputs the start instruction to the second power supply while power is being supplied from the control power supply;
After a predetermined first count time elapses after the drop in the first voltage is detected, the power supply from the control power supply to the start instruction element is stopped to stop the output of the start instruction. a timer;
4. The power switching device according to claim 3, further comprising: The second power supply continues to operate while an operation instruction indicating to continue operation is input,
The switching control circuit is
a first operation instruction element that outputs the operation instruction to the second power supply while power is supplied from the control power supply;
a second driving instruction element that outputs the driving instruction to the second power supply while power is being supplied from the second power supply;
After a predetermined second count time has passed since the power supply from the second power supply started, the electrical connection between the control power supply and the first operation instruction element is cut off to provide the first operation instruction. a second timer that stops outputting the operation instruction from the device;
5. The power switching device according to claim 4, further comprising: The switching control circuit cuts off the supply of power from the second power supply to the second drive instruction element in response to being pressed, thereby switching the power supply from the second drive instruction element to the second power supply. 6. The power switching device according to claim 5, further comprising an operation stop switch for stopping output of the operation instruction to stop the operation of the second power supply. The power switching device according to any one of claims 1 to 6, wherein the first power source and the second power source are portable generators. a first power supply;
a portable second power supply different from the first power supply;
a load to which power is supplied from either one of the first power supply and the second power supply;
a power supply switching device for switching a power supply for supplying power to the load from the first power supply to the second power supply;
The power switching device
a first terminal to which power is supplied from the first power supply;
a second terminal to which power is supplied from the second power supply;
a third terminal that supplies power to the load;
a power failure detection element that has a contact that opens while a first voltage applied to the first terminal is applied and closes while the first voltage is not applied, and detects that the first voltage has decreased;
a switching control circuit that starts a second power supply when a drop in the first voltage is detected;
a control power supply that supplies power to the switching control circuit;
The power failure detection element cuts off electrical connection between the second power supply and the control power supply and the switching control circuit by opening the contact while power is supplied from the first power supply to the load. do,
An emergency power supply system characterized by:

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