JP2003235163A - Method and apparatus for automatically switching power supply system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce manpower and prevent malfunction and troubles, such as load interruption, due to excess of the capacity of equipment by making it possible to automatically operate switches to select a power supply system for supplying power to the loads when power is supplied to the loads through a plurality of power supply systems. <P>SOLUTION: Switches 37 are used to select one or more power supply systems for supplying power to at least one load when power is supplied to loads through a plurality of power supply systems. Load sensors 35 grasp the amount of current or power supplied to the respective loads. Based on the grasped amount of current or power, the amount of power supplied through each power supply system is computed at a power supply switching arrangement 30. The power supply switching arrangement 30 operates the switches 37 so that the operation of each power supply system is made proper while preventing power supply to the loads from being interrupted. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention enables automatic switch operation for selecting a power supply system for supplying power to a load when power is supplied to the load from a plurality of power supply systems. The present invention relates to an automatic power supply system switching method and device capable of suppressing troubles and erroneous operations and suppressing failures such as load interruption due to excess of equipment capacity.

[0002]

2. Description of the Related Art When power is supplied from a plurality of power supply systems to a load, a switch is used to switch the connection between the power supply system and the load depending on the state of the load.

For example, in FIG. 4, the first power supply system 11 and the second power supply system 12 supply power to the first load 21 to the third load 23. Further, by operating the switch 39, the connection between the power supply system and the load can be switched by the switch. The power supply capacity of the equipment of the first power supply system 11 is Ea1 and the impedance is Za1. Further, the same capacity of the second power supply system 12 is Ea2 and the impedance is Za2.

At this time, if all the two switches 39 are turned on, the first power supply system 11 and the second power supply system 12 can be operated in cooperation with each other to cover the loads of the first load 21 to the third load 23. it can. In the operation, (Ea1: Ea
When the ratio of 2) is equal to the ratio of (Za2: Za1), the total power supply capacity of the first power supply system 11 and the second power supply system 12 is utilized to the maximum, and the first loads 21 to 3 The load 23 can be covered.

Further, in FIG. 4, the first power supply system 11
Depending on the situation of the second power supply system 12, the first load 21 to the third load 23, only one of these switches 39 may be turned on and operated.

For example, in FIG. 4, the first load 21 is connected to the first power supply system 11 regardless of the on / off state of the switch 39.
Power is supplied from the second power system 12 when the switch 39 on the left side in the figure is turned on. The second load 22 is supplied with power from the second power supply system 12 regardless of the on / off state of the switch 39, and the switch 39 on the right side of the drawing is used.
When is on, power is also supplied from the first power supply system 11. Then, the third load 23 is supplied with power by the first power supply system 11 only, the second power supply system 12 only, or by the first power supply system 11 and the second power supply system 12 depending on the on / off state of the two switches 39. It

Here, the switch 3 on the side of the first power supply system 11
Consider the case where 9 is on and the switch 39 on the second power system 12 side is off. In this case, the first power supply system 11 covers the first load 21 and the third load 23, and the second power supply system 12 covers the second load 22.

In such a switch state, the load of the first power supply system 11 exceeds the power supply capacity of the first power supply system 11, while the power supply capacity of the second power supply system 12 causes the second load 22 and the third load. Consider the case of being able to cover 23. In such a case, it can be considered that the following measures are taken.

(A1) Switch 3 on the side of the first power supply system 11
Switch 9 on the second power system 12 side with 9 turned on
9 is turned on, and both switches are turned on. That is, the first power supply system 11 and the second power supply system 12
Move to the linked operation of.

(A2) The load of the first power supply system 11 is suppressed so that it is within the range of the power supply capacity of the first power supply system 11. For example, the load is suppressed by turning off the first load 21 or the third load 23 or turning off a part of the first load 21 and the third load 23.

(A3) Switch 3 on the side of the first power supply system 11
Switch 9 on the second power system 12 side with 9 turned on
Turn on 9. Immediately thereafter, only the switch 39 on the first power supply system 11 side is turned off.

[0012]

However, all of the above (A1) to (A3) are manually performed, which is troublesome. In the case of (A1), (Ea1: Ea
If the ratio of 2) is not equal to the ratio of (Za2: Za1), the load is not properly shared with the first power supply system 11 and the second power supply system 12 that cooperate with each other, and one of them becomes overloaded. There is a risk. Further, in order to improve the impedance ratio, it is necessary to replace the transformer and other power system equipment, which is economically and time-consuming. (A
In the case of 2), the turned off load cannot be used, which causes a problem in operating the demand equipment. In the case of (A3), not only is it time-consuming for human labor, but there is a risk of erroneous operation, and there is a risk of load interruption in the first power supply system 11 and the second power supply system 12 due to overload.

Incidentally, Japanese Patent Laid-Open No. 54-161517 discloses a technique for automatically supplying power to a backup battery power supply device according to the degree of importance. However, it is premised on a DC power supply using a rectifier.

The present invention has been made to solve the above-mentioned conventional problems, and when supplying power to a load from a plurality of power supply systems, a switch operation for selecting a power supply system for supplying power to the load is performed. It is an object of the present invention to provide an automatic power system switching method and device that can be automatically performed to suppress human labor and erroneous operation, and can also suppress failures such as load shedding due to excess of equipment capacity.

[0015]

First, an automatic power supply system switching method according to the first invention of the present application is such that, when power is supplied to a load from a plurality of power supply systems, a current or an amount of power supplied to each load. And calculate the amount of power supplied by each power supply system based on these currents or amounts of power that have been acquired, so that the operation of each power supply system becomes appropriate.
The above-described problem is solved by operating a switch for selecting one or more power supply systems that supply power to at least one load while keeping the power supply to the load uninterrupted. .

Next, the automatic power supply system switching device of the second invention of the present application selects one or more power supply systems which supply power to at least one load when supplying power to the loads from a plurality of power supply systems. Switch for measuring, and a measurement sensor for grasping the amount of current or power supplied to each load,
Based on these grasped currents or amounts of power, load amount calculation unit that calculates the amount of power supplied by each power supply system, and the switch to the load so that the operation of each power supply system becomes appropriate. The above-described problem is solved by providing a switching determination processing unit that is operated while keeping the power supply of the device uninterrupted.

The operation of the present invention will be briefly described below.

According to the present invention, when power is supplied from a plurality of power supply systems to a load, the current or power amount supplied to each load is grasped. Then, the amount of electric power supplied by each power supply system is calculated based on the grasped current or electric energy.

In order to properly operate each power supply system, a switch for selecting one or more power supply systems supplying power to at least one load is provided so that the power supply to the load is not interrupted. To operate.

Therefore, in a comparatively simple manner, when power is supplied from a plurality of power supply systems to a load, a switch operation for selecting a power supply system for supplying power to the loads can be automatically performed to reduce labor and labor. By suppressing erroneous operations, it is possible to suppress obstacles such as load shedding due to excess equipment capacity.

Further, since the operation is performed while the power supply to the load is not interrupted, in the present invention, a state where a plurality of power supply systems are simultaneously connected to one load occurs in the switching operation process. May overload the power capacity of the power system. However, since the overload condition is short, no problems can occur. Conventionally, it is permissible to increase the load for a short time such as when starting the electric motor.

If the overload for such a short time is to be dealt with strictly, the short-term power supply capacity of each power supply system, that is, a predetermined short time, is larger than the normal power supply capacity. In consideration of the short-term power supply capacity, the switch operation for selecting the power supply system as described above may be performed. When a load that exceeds the power supply capacity for a short time occurs in the power supply system during the switch operation process, another switch operation may be performed to avoid the switch operation.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is an overall circuit diagram of the power supply system and load or automatic power supply system switching device of this embodiment.

In the present embodiment, the connection of the power supply system and the load is the same as in FIG. 4 of the above-mentioned conventional example.
Further, the automatic power supply system switching method and the automatic power supply system switching device of the present invention are applied to the connection. That is, the load amount sensor 35 that detects the current or power amount of each of the first load 21 to the third load 23 is arranged on the power supply line of the first load 21 to the third load 23. Further, instead of the switch 39 of FIG. 4, a switch 37 that can be turned on / off by an electric signal is used. These load sensors 3
The switch 5 and the switch 37 are connected to the power supply switching device 30.

FIG. 2 is a block diagram showing the internal structure of the power supply switching device 30.

As shown in this figure, the power source switching device 3
0 is the sensor signal input unit 40 and the load amount calculation calculation unit 50.
And a switching determination processing unit 32.

The sensor signal input section 40 is used for the load amount sensor 3
It has a plurality of load sensor input sections 41 to 43 provided for every five. These load sensor input units 41 to 43 output signals indicating the respective amounts of power of the first load 21 to the third load 23 in response to the signal from the load amount sensor 35.

The load amount calculation / calculation unit 50 calculates the amount of electric power of the load borne by each of the first power supply system 11 and the second power supply system 12. In the present embodiment, the load amount calculation calculation unit 5
0 has a first system load amount calculation unit 51 and a second system load amount calculation unit 52 for each power supply system, and calculates the power amount of the load of each power supply system by each of them. However, the present invention is not limited to this.

The first system load amount calculation unit 51 includes a switch 3
Depending on the on / off state of No. 7, the output of the load sensor input unit 41 is used as the amount of electric power of the load of the first power supply system 11, or the sum of the output of the load sensor input unit 41 and the output of the load sensor input unit 43 The electric power of the load of the first power supply system 11 is set, and a signal corresponding to the electric power is output. Similarly, the second
The system load amount calculation unit 52 sets the output of the load sensor input unit 42 as the power amount of the load of the second power supply system 12 according to the on / off state of the switch 37, or the load sensor input unit 4
The sum of the output of 2 and the output of the load sensor input unit 43 is used as the power amount of the load of the second power supply system 12, and a signal corresponding to the power amount is output.

The switching judgment processing section 32 operates the switch 37 on and off in response to a signal from the load amount calculation calculation section 50.

More specifically, in the present embodiment, the switching determination processing section 32 operates so that the switch 37 on the first power system 11 side is turned on when the following condition B1 is satisfied. And the switch 37 on the second power system 12 side
To turn off.

(B1) The sum of the electric energy of the first load 21 and the electric energy of the third load 23 is less than or equal to the power capacity Ea1 of the first power system 11.

If the conditions C1 and C2 listed below are both satisfied, the switching judgment processing unit 32 makes the first judgment.
The switch 37 on the power supply system 11 side is turned off, and the switch 37 on the second power supply system 12 side is turned on.

(C1) The total of the electric energy of the first load 21 and the electric energy of the third load 23 exceeds the power capacity Ea1 of the first power system 11.

(C2) The total amount of power of the second load 22 and the amount of power of the third load 23 is less than or equal to the power capacity Ea2 of the second power system 12.

If the condition of B1 is not satisfied and the condition of either C1 or C2 is not satisfied, the switching judgment processing unit 32 sounds an alarm as an overload.

The switching judgment processing section 32 ensures that at least one of the switches 37 is always turned on, including the process of the on / off operation of the switch 37.

For example, the switch 3 on the side of the first power supply system 11
When 7 is on and the switch 37 on the second power system 12 side is off, and the switch 37 on the first power system 11 side is off and the switch 37 on the second power system 12 side is on In the middle of the process, both switches 37 are turned on for only a short time,
At least one of the switches 37 is always turned on. Since the time is short, the problem of power capacity is unlikely to occur.

As described above, the present invention can be effectively applied to this embodiment. Therefore, when power is supplied to the load from multiple power supply systems, the switch operation for selecting the power supply system that supplies power to the loads can be automatically performed to suppress human labor and erroneous operation, and It is also possible to suppress obstacles such as load shedding due to excess capacity.

For example, it is possible to deal with the operating conditions of the first load 21 to the third load 23 as shown in the time chart of FIG. In FIG. 3, the high state indicates the operating state of the corresponding load, and the low state indicates the non-operating state.

In the present embodiment, if a short-time overload that occurs during the switching operation process of the switch 37 due to the above-described switch operation that prevents the power supply to the load from being interrupted is to be strictly handled. In consideration of the short-term power supply capacity of each power supply system, such a switch operation for selecting the power supply system may be performed. When a load that exceeds the power supply capacity for a short time occurs in the power supply system during the switch operation process, another switch operation may be performed to avoid the switch operation.

Specifically, the amount of electric power of the load for each power supply system in the process of operating the switch is calculated by the load amount calculation calculation unit 50. In the load amount calculation calculation unit 50, the load sensor input units 41 to 4 are operated by the first system load amount calculation unit 51 and the second system load amount calculation unit 52.
By appropriately using the output of No. 3, it is possible to calculate the electric power amount of the load for each power supply system in the process of operating such a switch. Then, when a load that exceeds the power supply capacity for a short time occurs in the power supply system, the switching determination processing unit 32 may avoid the switch operation and sound an alarm as an overload.

[0044]

According to the present invention, when power is supplied from a plurality of power supply systems to a load, a switch operation for selecting a power supply system for supplying power to the loads can be automatically performed, so that a manual operation can be performed. It is possible to suppress troubles and erroneous operations, and also to suppress obstacles such as load shedding due to excess of facility capacity.

[Brief description of drawings]

FIG. 1 is an overall circuit diagram of a power supply system, a load, or an automatic power supply system switching device according to this embodiment.

FIG. 2 is a block diagram showing the internal configuration of the power supply switching device of the above embodiment.

FIG. 3 is a time chart showing an example of a load operating condition in the embodiment.

FIG. 4 is a circuit diagram showing a connection example of a conventional power supply system and load.

[Explanation of symbols]

11 ... First power supply system 12 ... Second power supply system 21 ... First load 22 ... Second load 23 ... Third load 30 ... Power supply switching device 32 ... Switching determination processing unit 35 ... Load amount sensor 37, 39 ... Switch 40 ... Sensor signal input section 41 ... First load sensor input section 42 ... Second load sensor input section 43 ... Third load sensor input section 50 ... Load calculation calculation unit 51 ... First system load amount calculation unit 52 ... Second system load amount calculation unit

Claims (2)

[Claims] 1. When supplying power to a load from a plurality of power systems, the current or power amount supplied to each load is grasped, and each power system is based on the grasped current or electricity amount. To calculate the amount of power supplied by the power supply and to select one or more power supply systems that supply power to at least one load so that each power supply system operates properly. The automatic power supply system switching method is characterized in that the operation is performed so that there is no interruption. 2. A switch for selecting one or more power supply systems for supplying power to at least one load when supplying power to the loads from a plurality of power supply systems, and a current supplied to each load. Or, a measurement sensor that grasps the amount of power, a load amount calculation unit that computes the amount of power supplied by each power system based on these grasped currents or power amounts, and the operation of each power system becomes appropriate. As described above, the automatic power supply system switching device is provided with a switching determination processing unit that operates the switch while keeping the power supply to the load uninterrupted.