JPS6212337A - Power source switch - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a power supply switching device between a regular power supply (for example, a CVCF device) and a standby power supply (for example, a commercial power supply) that supplies power to a load that does not tolerate even instantaneous power outages. be.

[Conventional technology]

Figure 4 shows, for example, the magazine Ohm June 1983 issue P22.
4 is a configuration diagram of the conventional power supply switching device shown in FIG. 4, in which l is a regular power supply, 2 is a regular switch provided at the output end of the regular power supply 1, 3 is a backup power supply, and 4 is the backup power supply. A standby switch provided at the output end of the power source 3; 5, a synchronization control circuit for synchronizing the voltage phase of the regular power source 1 with the voltage phase of the backup power source 3; 6, the regular switch 2;
A switching control circuit 7 for controlling the opening and closing of the standby switch 4 and the standby switch 4 is an important load that is connected to the common terminal of the normal switch 2 and the standby switch 4 and does not tolerate even instantaneous power outages.

Next, the operation will be explained. The output of the regular power source 1 is supplied to the load 7 through the normally closed regular switch 2. The regular power supply 1 is synchronized with the standby power supply 3 by a synchronization control 5. If a failure occurs in the regular power supply 1 under the above conditions, a failure signal is sent to the switching control circuit 6, and as a result, the standby switch 4 is automatically closed instantaneously and the regular switch 2 is opened. , power is continuously supplied to the load 7 from the standby power source 3 without momentary interruption.

In manual operation, switching from the regular power source 1 to the standby power source 3 and vice versa is possible by applying manual operation to the switching control circuit 6.

However, if the regular power source 1 and the standby power source 3 are not synchronized, manual operation should not be performed in principle.

[Problem that the invention seeks to solve]

Since the conventional power supply switching device is configured as described above, when maintenance and inspection of the regular power supply 1 is carried out, it is necessary to switch to the standby power supply 3 by manual operation. You won't know until you actually switch. Further, when switching back from the standby power source 3 to the regular power source 1 after the maintenance and inspection of the regular power source 1 is completed, the result cannot be known unless the switch is actually made. In the unlikely event that there is an abnormality in the switching circuit,
There were problems such as the need to interrupt power supply to the load for repairs.

This invention was made to solve the above-mentioned problems, and it is possible to actually check the operation of the switching circuit before switching the power supply to the load, and if there is an abnormality in the switching circuit, the load To provide a power supply switching device capable of carrying out repairs without interrupting power supply to the equipment, confirming the repair results, and then switching from a regular power supply to a standby power supply.

[Means for solving problems]

The power supply switching device according to the present invention includes a bypass circuit having a normally open maintenance switch between at least one of the regular power source or the standby power source and the load, and a normally closed bypass circuit having a normally open maintenance switch between the output end of the regular power source and the regular switch. The repair switch is provided with a normally closed maintenance switch between the normally closed switch and the load.

[For production]

In this invention, the load is supplied with power via the bypass circuit by opening the normally closed repair switch and maintenance switch and closing the normally open maintenance switch. Repair the disconnected switching control circuit.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. 1, in which the same parts as in FIG. 4 are denoted by the same reference numerals.

In Fig. 1, 8 is a regular switch 2 and a standby switch 4.
9 is a second maintenance switch provided in the bypass circuit 13 between the regular power supply 1 and the load 7, and 10 is a standby power supply. 3 and the load 7; 11 is a first repair switch provided at the output end of the regular power supply 1; and 12 is a first repair switch provided at the output end of the standby power supply 3. This is the second repair switch.

In the figure, Kl eK2 is a contact point that opens and closes control circuit signals between the commercial power supply 1 and the synchronous control circuit 5 and switching control circuit 6. This does not necessarily have to be the case, as long as consideration is given to avoid the exchange of information.

Next, the operation will be explained. Normally, the first maintenance switch 8 is closed, and the second maintenance switch 9 and the third maintenance switch 1 are closed.
0 means open, and the first repair switch 11 and second repair switch 12 are closed.

The output of the regular power source 1 is supplied to the load 7 through the closed regular switch 2. The regular power supply 1 is synchronized with the backup power supply 3 by a synchronization control circuit 5.

In the above situation, if a failure occurs in the regular power supply 1, a failure signal is sent from the regular power supply 1 to the switching control circuit 6, and as a result, the standby switch 4 is automatically closed instantaneously, and the regular switch is automatically closed. If 2 is open, the standby power supply 3 is supplied to the load 7 without momentary interruption.
Power supply continues.

When switching from the regular power source 1 to the standby power source 3 during manual operation, the following steps apply. First, close the second maintenance switch 9 and bypass the regular power supply 1 to the load 7 via the bypass circuit, then open the first maintenance switch 8,
The regular switch 2 and the standby switch 4 are separated from the load 7. In this state, the switching control circuit 6, the regular switch 2, and the standby switch 4 are operated by manual operation, and it is confirmed that switching occurs without momentary interruption.

If there is an abnormality in the operation of the switching control circuit 6 at this time, the switching control circuit 6 is separated from the regular power supply 1 and the standby power supply 3 and repaired using the following procedure. First, the first
Open the repair switch 11 and turn on the regular power supply 1 and the regular switch 2.
Separate. Next, the second repair switch 12 is opened to separate the backup power supply 3 and the backup switch 4. If necessary, open the contact by 1°Km to prevent erroneous control signals from being generated.

After taking the above measures, repair the malfunctioning part. When the repair is completed, return the first repair switch 11 and the repair switch 2 of WJ2 to the closed position, close the contact with 1-kg, and then perform an operation test of the switching control circuit 6. After returning the backup switch 4 to the open position and reconfirming that switching occurs without momentary interruption, the first maintenance switch 8 is closed, and then the second maintenance switch 9 is opened. Since the operation confirmation of the switching control circuit 6 is completed above, the actual switching operation is then performed manually to supply power from the backup power source 3 to the multi-load 7.

Next, when switching from a state in which power is being supplied to the load 7 from the standby power source 3 to the regular power source 1, the third maintenance switch 10 is closed, and then the first maintenance switch 8 is opened. .

In this state, the operation of the switching control circuit 6 is confirmed, and if any abnormality is found, repairs are carried out in the same manner as in the case of switching from the regular power source 1 to the standby power source 3, and the operation is reconfirmed. Finally, the spare switch 4 is closed, the regular switch 2 is returned to open, and the first maintenance switch 8 is closed. Thereafter, the third maintenance switch 10 is opened to perform actual switching by manual operation.

In the above embodiment, the first and second repair switches 11.
12 and the first, second, and third maintenance switches 8 to 10, switching control can be performed without interrupting the power supply to the load 7 even when power is being supplied to the load 7 from either the regular power supply 1 or the standby power supply 3. Although it is possible to check the operation of the circuit 6 and repair it in case of abnormality, if only the third maintenance switch 10 is omitted as shown in FIG. The switching control circuit 6 can be maintained and repaired.

Furthermore, if the backup power supply 3 can be stopped, repairs can be performed by separating the switching control circuit from the regular power supply 1 and the backup power supply 3 even if the second repair switch 12 is omitted as shown in FIG. It is. In this way, depending on the conditions on the power supply side, either the first repair switch 11 or the second repair switch 12 may be omitted. Further, depending on maintenance conditions, either the second maintenance switch 9 or the third maintenance switch 10 may be omitted.

In the above embodiment, the regular switch 2 is configured with a mechanical switch, but it may also be a semiconductor switch such as a thyristor like the standby switch 4. [Effects of the Invention] As described above, according to the present invention, For example, a bypass circuit with a normally open maintenance switch is installed between the load of at least one of the regular power supply or standby power supply, and a test is performed to confirm the operation of the switching control circuit while supplying power to the load via this bypass circuit to detect abnormalities. If there is a problem, the switching control circuit is separated from the power supply and repaired, and then the switching can be performed by actual switching operation, so the effect is that a power switching device with extremely high reliability and maintainability can be obtained. There is.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a power switching device according to an embodiment of the invention, FIG. 2 is a block diagram showing another embodiment of the invention, and FIG. 3 is a block diagram showing yet another embodiment of the invention. 4 is a block diagram of a conventional power switching device. 0 1 is a regular power source, 2 is a regular switch, 3 is a backup power source, 4 is a backup switch, 5 is a synchronous control circuit, and 6 is a switching control circuit,
7 is a load, 8 is a normally closed maintenance switch, 9 is a normally open maintenance switch, and 11 is a normally closed repair switch. In the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] A regular switch provided at the output end of the regular power source, a backup switch provided at the output end of the backup power source, a load supplied with power via either of the two switches, a voltage phase of the regular power source, and the backup power source. If the power supply in use fails, the synchronization control circuit synchronizes the voltage phase of the
In a power supply switching device having a switching control circuit that opens and closes two switches to supply power from another power source to the load without momentary interruption, the normally open switch provided between at least one of the regular power source or the backup power source and the load. a bypass circuit having a maintenance switch, a normally closed repair switch provided between the service power source and the service switch, and a normally closed maintenance switch provided between the service switch and the load. A power switching device characterized by: