JP7000298B2 - Power supply system and control method of power supply system - Google Patents

Description

The present invention relates to a power supply system in which a plurality of AC output converters that convert power from direct current to alternating current are connected in parallel to supply power to a load.

A power supply system is known in which a plurality of AC output converters that convert power from direct current to alternating current are connected in parallel to supply power to a load.

In this regard, Japanese Patent Application Laid-Open No. 2017-50933 discloses a power supply system in which a plurality of AC output converters such as inverters are connected in parallel and operated in parallel with respect to a common load.

Japanese Unexamined Patent Publication No. 2017-50933

On the other hand, the power supply system in the above publication can supply power with high efficiency by supplying power to the load from each AC output converter. For example, in the event of a power failure, power is supplied from the storage battery to the load. Supply.

However, after a power outage occurs, the power supply capacity from the storage battery to the load may differ for each AC output converter.

In that case, if the power supply capacity from the AC output converter is set uniformly, the supply period may be different for each AC output converter. That is, there is a possibility that the period for performing parallel operation with a plurality of AC output converters will be shortened.

An object of the present invention is to solve the above problems, and to realize a power supply system that enables efficient parallel operation with a plurality of AC output converters in the event of a power failure.

It is a power supply system according to a certain aspect, and includes a plurality of AC output converters connected in parallel to supply power to an AC load, and a management device for managing the power supplied from the plurality of AC output converters to the AC load. Each AC output converter is connected in parallel with an AC / DC converter that converts an external AC voltage to a DC voltage, a DC AC converter that converts a DC voltage into an AC voltage and supplies it to an AC load, and a DC AC converter. It includes a plurality of secondary batteries for storing a DC voltage and supplying power in the event of a power failure of an external AC voltage. The management device adjusts the power supplied from the DC AC converter to the AC load based on the state of each of the plurality of secondary batteries of the plurality of AC output converters in the event of a power failure of the external AC voltage.

Preferably, the management device checks the status of each of the plurality of secondary batteries of the plurality of AC output converters in the event of a power failure of the external AC voltage.

Preferably, the management device checks the status of each of the plurality of secondary batteries of the plurality of AC output converters in the event of a power failure of the external AC voltage, and sets the abnormal secondary battery to be unusable.

Preferably, each AC output converter further comprises a plurality of switching circuits provided corresponding to each of the plurality of secondary batteries. The management device checks the status of each of the plurality of secondary batteries of the plurality of AC output converters in the event of a power failure of the external AC voltage, and sets the switching circuit corresponding to the abnormal secondary battery to off.

Preferably, the management device checks the status of each of the plurality of secondary batteries of the plurality of AC output converters in the event of a power failure of the external AC voltage, and removes the abnormal secondary battery as a whole of the normal secondary battery. The power supplied from the DC / AC output converter to the AC load is adjusted based on the number.

Preferably, the management device checks the status of each of the plurality of secondary batteries of the plurality of AC output converters in the event of a power failure of the external AC voltage, and is supplied from a normal secondary battery excluding the abnormal secondary battery. The power supplied from the DC / AC output converter to the AC load is adjusted based on the current value.

Preferably, the management device checks the status of each of the plurality of secondary batteries of the plurality of AC output converters in the event of a power failure of the external AC voltage, and the remaining amount of the normal secondary battery excluding the abnormal secondary battery. The power supplied from the DC / AC output converter to the AC load is adjusted based on.

The power supply system of the present invention enables efficient parallel operation with a plurality of AC output converters in the event of a power failure.

It is a figure explaining the structure of the uninterruptible power supply system 1 based on the embodiment. It is a schematic diagram of the power supply with respect to the load 20 at the time of a power failure based on the embodiment. It is a figure explaining the power supply of the storage batteries 6-1 to 6-4 of the AC output converters 10-1 and 10-2 at the time of a power failure based on an embodiment. It is a figure explaining the power supply of the conventional uninterruptible power supply system at the time of a power failure. It is a schematic diagram of the power supply to the load 20 of the conventional uninterruptible power supply system at the time of a power failure. It is a figure explaining the power supply of the storage batteries 6-1 to 6-4 of the conventional AC output converters 10-1 and 10-2 at the time of a power failure. It is a schematic diagram of the power supply of the storage battery of the conventional AC output converter 10 at the time of a power failure. It is a figure explaining the calculation of the burden sharing ratio of the management apparatus 15 based on an embodiment. It is a schematic diagram of the power supply to the load 20 at the time of a power failure of the uninterruptible power supply system 1 based on the embodiment. It is another figure explaining the power supply of the storage batteries 6-1 to 6-4 of the AC output converters 10-1 and 10-2 at the time of a power failure based on an embodiment. It is a figure explaining the calculation of the burden sharing ratio of the management apparatus 15 based on the modification 1 of an embodiment. It is a figure explaining the calculation of the burden sharing rate of the uninterruptible power supply system based on the modification 1 of the embodiment. It is a figure explaining the calculation of the burden sharing ratio of the management apparatus 15 based on the modification 2 of the embodiment. It is a figure explaining the calculation of the burden sharing rate of the uninterruptible power supply system based on the modification 2 of the embodiment.

Hereinafter, embodiments will be described with reference to the drawings. In this example, an uninterruptible power supply system (hereinafter referred to as UPS (Uninterruptible Power Supply)) will be described as an example of a power supply system.

In this embodiment, a parallel configuration of a plurality of AC output converters will be described in an uninterruptible power supply system.

FIG. 1 is a diagram illustrating a configuration of an uninterruptible power supply system 1 based on an embodiment.
With reference to FIG. 1A, the uninterruptible power supply system 1 has a common load from a plurality of (n) AC output converters 10-1 to 10-n and AC output converters 10-1 to 10-n. A management device 15 for managing the electric power supplied to the 20 is included. The AC output converters 10-1 to 10-n (collectively referred to as AC output converters 10) are connected to the external AC power supply 3 and operate in parallel with respect to the common load 20. It should be noted that the number of n can be set to an arbitrary value depending on the load to be supplied, particularly if the number is two or more. As an example, a configuration including two AC output converters 10-1 and 10-2 will be described.

Hereinafter, the configuration of each AC output converter 10 will be described.
The AC output converter 10 is connected to an external AC power supply 3 and has a converter 5 that converts an AC voltage from the external AC power supply 3 into a DC voltage, and an inverter 7 that is connected to the converter 5 and converts a DC voltage into an AC voltage. Includes a power storage device 11 connected to the converter 5 in parallel with the inverter 7, and a switching circuit 2 provided between the power storage device 11 and the inverter 7. The power storage device 11 has a plurality of storage batteries 6-1 to 6-4 connected in parallel to each other and switching circuits (switches) 4-1 to 4-1 to be provided corresponding to the plurality of storage batteries 6-1 to 6-4, respectively. Includes 4-4.

The AC output converter 10 includes a switching circuit 9 provided between the inverter 7 and the load, a bypass path provided separately from the supply paths of the converter 5 and the inverter 7, and a bypass path and a load. Further includes a switching circuit 8 provided between and.

When the power supply to the external AC power supply 3 is stopped due to a power failure, the power storage device 11 supplies power to the load.

When the external AC power supply 3 stops supplying electric power due to a power failure, the management device 15 controls various switching circuits and manages the electric power supplied to the load 20.

In the normal state when the external AC power supply 3 is operating normally, the switching circuit 9 is on and the load 20 and the inverter 7 are connected.

The converter 5 converts the AC voltage from the external AC power supply 3 into a DC voltage. The inverter 7 is connected to the converter 5 and converts a DC voltage into an AC voltage. Further, the storage battery 6 stores the DC voltage converted by the converter 5.

Power is supplied from the inverter 7 to the load 20 via the switching circuit 9.
Since the plurality of AC output converters 10 are arranged in parallel, the necessary power is supplied from each AC output converter 10 to the load 20.

In this example, the AC output converter 10 supplies 50% of the power required for the load 20 with respect to the load 20.

FIG. 1B is a diagram illustrating power supply of the uninterruptible power supply system 1 at the time of a power failure based on the embodiment with reference to FIG. 1 (B).

A case where the external AC power supply 3 has a power failure will be described.
In this case, the voltage supply from the converter 5 is reduced, so that the switching circuit 2 is turned on.

Then, the power supply to the load 20 is continued from the power storage device 11 via the inverter 7 and the switching circuit 9. In this state, the switching circuit 8 is off.

In this example, the AC output converter 10 continues to supply 50% of the power required for the load 20 with respect to the load 20.

FIG. 2 is a schematic diagram of power supply to the load 20 at the time of a power failure based on the embodiment.
As shown in FIG. 2, each AC output converter 10 supplied 50% of the power to the load 20 before the power failure.

Each storage battery 6 supplies 12.5% of the electric power in order to continue supplying 50% of the electric power to the load 20 even after the power failure.

FIG. 3 is a diagram illustrating power supply of the storage batteries 6-1 to 6-4 of the AC output converters 10-1 and 10-2 at the time of a power failure based on the embodiment.

As shown in FIG. 3, eight storage batteries 6 are connected to the load 20, and each storage battery 6 supplies 12.5% of the power required for the load 20.

Therefore, since the power of the storage battery 6 is consumed evenly, the period during which the plurality of AC output converters 10-1 and 10-2 operate in parallel with each other is secured for a long period of time. Therefore, if the power failure state is restored during the period and the power is restored, it is possible to recover during the period when the plurality of AC output converters 10 are operating in parallel.

FIG. 4 is a diagram illustrating power supply of a conventional uninterruptible power supply system at the time of a power failure.
FIG. 4A shows a case where the external AC power supply 3 has a power failure.

Further, the case where the storage batteries 6-1 and 6-2 of the AC output converter 10-2 are out of order is shown. Therefore, power is supplied to the load 20 from the storage batteries 6-3 and 6-4.

In this example, the AC output converter 10 continues to supply 50% of the power required for the load 20 with respect to the load 20.

FIG. 4B shows a case where the state of FIG. 4A continues after the external AC power supply 3 has a power failure.

If the storage batteries 6-1 and 6-2 of the AC output converter 10-2 are out of order, the power supplied from the storage batteries 6-3 and 6-4 to the load 20 is consumed so much that the AC output is output. The converter 10-2 stops.

Therefore, the AC output converter 10-1 continues to supply 100% of the power required for the load 20.

FIG. 5 is a schematic diagram of power supply to the load 20 of the conventional uninterruptible power supply system at the time of a power failure.

As shown in FIG. 5A, each AC output converter 10 supplied 50% of the power to the load 20 before the power failure.

Even after a power failure, 50% of the power supply to the load 20 is continued. Therefore, the AC output converter 10-2 needs to supply 50% of the power to the load 20 only by the storage batteries 6-3 and 6-4. Therefore, the storage batteries 6-3 and 6-4 each supply 25% of the power required for the load 20. The storage batteries 6-1 to 6-4 of the AC output converter 10-1 each supply 12.5% of the power required for the load 20.

As shown in FIG. 5B, after the external AC power supply 3 fails, the AC output converter 10-1 continues to supply 100% of the power required for the load 20.

The storage batteries 6-1 to 6-4 of the AC output converter 10-1 each supply 25% of the power required for the load 20.

FIG. 6 is a diagram illustrating power supply of the storage batteries 6-1 to 6-4 of the conventional AC output converters 10-1 and 10-2 at the time of a power failure.

As shown in FIG. 6, two storage batteries are stopped due to a failure.
The storage batteries 6-3 and 6-4 of the AC output converter 10-2 each supply 25% of the power required for the load 20. The storage batteries 6-1 to 6-4 of the AC output converter 10-1 each supply 12.5% of the power required for the load 20.

As shown in the figure, the storage batteries 6-3 and 6-4 consume twice as much power as the state shown in FIG.

Therefore, the period during which the plurality of AC output converters 10-1 and 10-2 operate in parallel with each other is half the period shown in FIG.

Therefore, it becomes difficult to recover during the period when the plurality of AC output converters 10 are operating in parallel, and when recovering from the completely stopped state, the recovery time becomes longer than when returning during operation. there is a possibility.

FIG. 7 is a schematic diagram of the power supply of the storage battery of the conventional AC output converter 10 at the time of a power failure.
As shown in FIG. 7A, the AC output converter 10-1 supplied 50% of the power to the load 20 before the power failure. Each storage battery 6 supplies 12.5% of the electric power in order to continue supplying 50% of the electric power to the load 20 even after the power failure.

Further, the AC output converter 10-2 supplied 50% of the power to the load 20 before the power failure. Even after a power failure, 50% of the power supply to the load 20 is continued. In this case, since the two storage batteries 6 are out of order, the storage batteries 6-3 and 6-4 each supply 25% of the electric power.

As shown in FIG. 7B, the case where the power of the AC output converter 10-2 is stopped is shown. The AC output converter 10-1 needs to supply 100% of the power to the load 20. Therefore, in order to continue supplying 100% of the electric power to the load 20, the storage batteries 6-1 to 6-4 each supply 25% of the electric power.

FIG. 8 is a diagram illustrating the calculation of the burden sharing rate of the management device 15 based on the embodiment.

As shown in FIG. 8, the management device 15 counts the normal number of storage batteries 6 of the AC output converters 10-1 and 10-2. The management device 15 confirms the state of the storage battery 6 of the power storage device 11 of the AC output converters 10-1 and 10-2. When the management device 15 determines that the state of the storage battery 6 is abnormal, the management device 15 sets the corresponding switching circuit 4 to off. In this example, the switching circuits 4-1 and 4-2 of the storage batteries 6-1 and 6-2 of the AC output converter 10-1 are set to off.

The management device 15 distributes the load evenly by totaling the total number of normal units of the storage battery 6 excluding the storage battery in the abnormal state. Specifically, the load is shared so as to be uniform according to the number of normal storage batteries 6 included in the AC output converter 10.

In this example, the number of normal storage batteries 6 is six. Therefore, the burden ratio for supplying the necessary electric power to the load 20 is 16.7% in each storage battery 6.

FIG. 9 is a schematic diagram of power supply to the load 20 at the time of a power failure of the uninterruptible power supply system 1 based on the embodiment.

As shown in FIG. 9, each AC output converter 10 supplied 50% of the power to the load 20 before the power failure.

After a power failure, the ratio of the power burden to the load 20 is adjusted according to the number of normal storage batteries 6.

The management device 15 totals the total number of normal storage batteries 6 and evenly distributes the load. Specifically, the load is shared so as to be uniform according to the number of normal storage batteries 6 included in the AC output converter 10.

In this example, the number of normal storage batteries 6 is six. Therefore, the burden ratio for supplying the necessary electric power to the load 20 is 16.7% in each storage battery 6.

The AC output converter 10-1 uses the storage batteries 6-1 to 6-4 to supply 66.7% of the electric power to the load 20. Further, the AC output converter 10-2 uses the storage batteries 6-3 and 6-4 to supply 33.3% of the electric power to the load 20.

FIG. 10 is another diagram illustrating the power supply of the storage batteries 6-1 to 6-4 of the AC output converters 10-1 and 10-2 at the time of a power failure based on the embodiment.

As shown in FIG. 10, six storage batteries 6 are connected to the load 20, and each storage battery 6 supplies 16.7% of the power required for the load 20.

Therefore, since the power of the storage battery 6 is consumed evenly, the period during which the plurality of AC output converters 10-1 and 10-2 operate in parallel with each other is secured for a long period of time. Therefore, if the power failure state is restored during the period and the power is restored, it is possible to recover during the period when the plurality of AC output converters 10 are operating in parallel. That is, in the state of FIG. 6, it was possible to secure a period of operating in parallel for only half of the period, but with this method, it is possible to secure a period of two-thirds of the period of FIG. 3, and each other. It is possible to extend the period of parallel operation as much as possible. Therefore, if the power failure state is restored during the period and the power is restored, it is possible to recover during the period when the plurality of AC output converters 10 are operating in parallel.

(Variation example 1)
In the above embodiment, a method of adjusting the load sharing ratio according to the number of normal storage batteries 6 has been described.

On the other hand, the sharing rate is not limited to this, and the sharing ratio may be adjusted by another method.
For example, the load sharing ratio may be adjusted according to the amount of flowing current.

FIG. 11 is a diagram illustrating the calculation of the burden sharing ratio of the management device 15 based on the modification 1 of the embodiment.

As shown in FIG. 11, the management device 15 measures the amount of current flowing from the storage batteries 6 of the AC output converters 10-1 and 10-2, respectively. The management device 15 confirms the state of the storage battery 6 of the power storage device 11 of the AC output converters 10-1 and 10-2. When the management device 15 determines that the state of the storage battery 6 is abnormal, the management device 15 sets the corresponding switching circuit 4 to off. In this example, the switching circuits 4-1 and 4-2 of the storage batteries 6-1 and 6-2 of the AC output converter 10-1 are set to off.

The management device 15 evenly distributes the load based on the amount of current measured by the storage battery 6. Specifically, the amount of current flowing from each of the storage batteries 6-1 to 6-4 of the AC output converter 10-1 and the current amounts I11 to I14 and from each of the storage batteries 6-1 to 6-4 of the AC output converter 10-2. The load is shared so as to be uniform based on the amount of current I21 to I24 flowing.

Specifically, the maximum current amount IB1 of the current amounts I11 to I14 flowing from each of the storage batteries 6-1 to 6-4 of the AC output converter 10-1 and the storage batteries 6-1 to 6 of the AC output converter 10-2. The load is shared so as to be uniform based on the maximum current amount IB2 of the current amounts I21 to I24 flowing from each of -4.

The load is adjusted based on the sum of the maximum current amounts IB1 and IB2.
FIG. 12 is a diagram illustrating the calculation of the burden sharing rate of the uninterruptible power supply system based on the first modification of the embodiment.

As shown in FIG. 12, as an example, a case where a load power of 200 kW is applied to the AC output converters 10-1 and 10-2 will be described. Further, it is assumed that each storage battery 6-1 to 6-4 can supply a voltage of 500 V.

In this case, the amount of current flowing through each of the storage batteries 6-1 to 6-4 of the AC output converter 10-1 is 100 A (200 kW / 500 V / 4 units).

On the other hand, it is assumed that the storage batteries 6-1 and 6-2 of the AC output converter 10-2 are out of order. Then, it is assumed that the storage batteries 6-3 and 6-4 can supply a voltage of 470V.

In this case, the amount of current flowing through each of the storage batteries 6-3 to 6-4 of the AC output converter 10-2 is 213A (200kW / 470V / 2 units).

The management device 15 calculates the burden sharing ratio based on the maximum current amount IB1 (100A) and the maximum current amount IB2 (213A).

Specifically, the burden sharing ratio of the AC output converter 10-1 is set to 68% (IB2 / (IB1 + IB2)).

Further, the burden sharing ratio of the AC output converter 10-2 is set to 32% (IB1 / (IB1 + IB2)).

As a result, the amount of current flowing from the storage batteries 6-1 to 6-4 of the AC output converter 10-1 increases from 100 A to 136 A.

Further, the amount of current flowing from the storage batteries 6-3 and 6-4 of the AC output converter 10-2 is reduced from 213A to 136A.

Since the amount of current flowing from each storage battery 6 is equalized and the power of each storage battery 6 is consumed uniformly, a period in which the plurality of AC output converters 10-1 and 10-2 operate in parallel with each other is secured for a long period of time. To. Therefore, if the power failure state is restored during the period and the power is restored, it is possible to recover during the period when the plurality of AC output converters 10 are operating in parallel. That is, in the state of FIG. 6, it was possible to secure a period of operating in parallel for only half of the period, but with this method, it is possible to secure a period of two-thirds of the period of FIG. 3, and each other. It is possible to extend the period of parallel operation as much as possible. Therefore, if the power failure state is restored during the period and the power is restored, it is possible to recover during the period when the plurality of AC output converters 10 are operating in parallel.

The above is an example, and another method may be adopted.
(Modification example 2)
The load sharing ratio may be adjusted according to the remaining amount of the storage battery 6.

FIG. 13 is a diagram illustrating the calculation of the burden sharing ratio of the management device 15 based on the modification 2 of the embodiment.

As shown in FIG. 13, the management device 15 measures the remaining amount of the storage batteries 6 of the AC output converters 10-1 and 10-2, respectively. The management device 15 confirms the state of the storage battery 6 of the power storage device 11 of the AC output converters 10-1 and 10-2. When the management device 15 determines that the state of the storage battery 6 is abnormal, the management device 15 sets the corresponding switching circuit 4 to off. In this example, the switching circuits 4-1 and 4-2 of the storage batteries 6-1 and 6-2 of the AC output converter 10-1 are set to off.

The management device 15 evenly distributes the load based on the remaining amount measured by the storage battery 6. Specifically, the remaining amount P11 to P14 of the storage batteries 6-1 to 6-4 of the AC output converter 10-1 and the remaining amount P21 to P24 of the storage batteries 6-1 to 6-4 of the AC output converter 10-2. Share so that the load is even.

Specifically, the remaining amount P1 of the remaining amount P11 to P14 of the storage batteries 6-1 to 6-4 of the AC output converter 10-1 and the storage batteries 6-1 to 6-4 of the AC output converter 10-2. The load is shared so as to be even based on the minimum remaining amount P2 of the remaining amount P21 to P24.

The load is adjusted based on the sum of the minimum remaining amount P1 and P2.
FIG. 14 is a diagram illustrating the calculation of the burden sharing rate of the uninterruptible power supply system based on the second modification of the embodiment.

As shown in FIG. 14, as an example, a case where a load power of 200 kW is applied to the AC output converters 10-1 and 10-2 will be described. The remaining amount P11 to P14 is 80% or 79%.

On the other hand, it is assumed that the storage batteries 6-1 and 6-2 of the AC output converter 10-2 are out of order. Further, since the remaining amount P21 and P22 do not operate due to a failure, the remaining amount is set to 100%. Further, the remaining amounts P23 and P24 of the storage batteries 6-3 and 6-4 of the AC output converter 10-2 are 59% or 60%.

The management device 15 calculates the burden sharing rate based on the minimum remaining amount P1 (79%) and the minimum remaining amount P2 (59%).

Specifically, the burden sharing ratio of the AC output converter 10-1 is set to 57% (P1 / (P1 + P2)).

Further, the burden sharing ratio of the AC output converter 10-2 is set to 43% (P2 / (P1 + P2)).

As a result, the load of the AC output converter 10-1 increases from 50% to 57% as a whole.

Further, the load of the AC output converter 10-2 is reduced from 50% to 43% as a whole.
Adjust so that the remaining amount of each storage battery 6 is uniform. As a result, the storage battery 6 is consumed uniformly, so that a period during which the plurality of AC output converters 10-1 and 10-2 operate in parallel with each other is secured for a certain long period of time. Therefore, if the power failure state is restored during the period and the power is restored, it is possible to recover during the period when the plurality of AC output converters 10 are operating in parallel. That is, in the state of FIG. 6, it was possible to secure a period of operating in parallel for only half of the period, but with this method, it is possible to secure a period of two-thirds of the period of FIG. 3, and each other. It is possible to extend the period of parallel operation as much as possible. Therefore, if the power failure state is restored during the period and the power is restored, it is possible to recover during the period when the plurality of AC output converters 10 are operating in parallel.

Although the embodiments of the present invention have been described above, it should be considered that the embodiments disclosed this time are exemplary in all respects and are not restrictive. The scope of the present invention is indicated by the scope of claims and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 Uninterruptible power supply system, 2,8,9 switching circuit, 3 External AC power supply, 5 Converter, 6 Storage battery, 7 Inverter, 10-1, 10-2 AC output converter, 11 Power storage device, 15 Management device, 20 Load ..

Claims (6)

Multiple AC output converters connected in parallel to supply power to the AC load,
A management device for managing the power supplied from the plurality of AC output converters to the AC load is provided.
Each AC output converter
An AC / DC converter that converts an external AC voltage to a DC voltage,
A DC-AC converter that converts the DC voltage into an AC voltage and supplies it to the AC load.
It includes a plurality of secondary batteries connected in parallel with the DC AC converter to store the DC voltage and supply power in the event of a power failure of the external AC voltage.
The management device is
When the external AC voltage fails, the status of each of the plurality of secondary batteries of the plurality of AC output converters is confirmed, and the current value supplied from the normal secondary batteries excluding the abnormal secondary battery is set. Based on this, the power supplied from the DC AC converter to the AC load is adjusted.
In each of the AC output converters, the maximum current value supplied from the normal secondary battery included in the AC output converter is acquired, and the load sharing ratio is calculated based on the ratio of the acquired maximum current values. , A power supply system that adjusts the power supplied from the DC AC converter to the AC load according to the calculated load sharing ratio . Multiple AC output converters connected in parallel to supply power to the AC load,
A management device for managing the power supplied from the plurality of AC output converters to the AC load is provided.
Each AC output converter
An AC / DC converter that converts an external AC voltage to a DC voltage,
A DC-AC converter that converts the DC voltage into an AC voltage and supplies it to the AC load.
It includes a plurality of secondary batteries connected in parallel with the DC AC converter to store the DC voltage and supply power in the event of a power failure of the external AC voltage.
The management device is
When the external AC voltage fails, the status of each of the plurality of secondary batteries of the plurality of AC output converters is confirmed, and the remaining amount of the normal secondary batteries excluding the abnormal secondary battery is used as the basis. Adjust the power supplied from the DC AC converter to the AC load,
In each of the AC output converters, the minimum remaining amount of the normal secondary battery contained in the AC output converter is acquired, and the load sharing ratio is calculated and calculated based on the ratio of the acquired minimum remaining amount. A power supply system that adjusts the power supplied from the DC AC converter to the AC load according to the load sharing ratio . The management device confirms the state of each of the plurality of secondary batteries of the plurality of AC output converters in the event of a power failure of the external AC voltage, and sets the abnormal secondary battery to be unusable. Or the power supply system according to 2 . Each AC output converter further includes a plurality of switching circuits provided corresponding to the plurality of secondary batteries.
The management device confirms the state of each of the plurality of secondary batteries of the plurality of AC output converters when the external AC voltage fails, and sets the switching circuit corresponding to the abnormal secondary battery to off. , The power supply system according to claim 3. It is a control method of a power supply system that manages the power supplied to the AC load from a plurality of AC output converters connected in parallel to supply power to the AC load.
Each of the AC output converters includes an AC / DC converter that converts an external AC voltage into a DC voltage, a DC AC converter that converts the DC voltage into an AC voltage and supplies the AC load, and the DC AC converter. Including a plurality of secondary batteries for storing the DC voltage and supplying power in the event of a power failure of the external AC voltage.
A step of confirming the state of each of the plurality of secondary batteries of the plurality of AC output converters in the event of a power failure of the external AC voltage, and a step of confirming the status of the plurality of secondary batteries.
A step of adjusting the power supplied from the DC AC converter to the AC load based on the current value supplied from the normal secondary battery excluding the abnormal secondary battery is provided.
The step of adjusting the power is
In each of the AC output converters, a step of acquiring the maximum current value supplied from a normal secondary battery included in the AC output converter, and a step of acquiring the maximum current value, respectively.
The step of calculating the load sharing ratio based on the ratio of the acquired maximum current value, and
A method for controlling a power supply system, comprising a step of adjusting the power supplied from the DC AC converter to the AC load according to a calculated load sharing ratio . It is a control method of a power supply system that manages the power supplied to the AC load from a plurality of AC output converters connected in parallel to supply power to the AC load.
Each of the AC output converters includes an AC / DC converter that converts an external AC voltage into a DC voltage, a DC AC converter that converts the DC voltage into an AC voltage and supplies the AC load, and the DC AC converter. Including a plurality of secondary batteries for storing the DC voltage and supplying power in the event of a power failure of the external AC voltage.
A step of confirming the state of each of the plurality of secondary batteries of the plurality of AC output converters in the event of a power failure of the external AC voltage, and a step of confirming the status of the plurality of secondary batteries.
A step of adjusting the power supplied from the DC AC converter to the AC load based on the current value supplied from the normal secondary battery excluding the abnormal secondary battery is provided.
In each of the AC output converters, a step of acquiring the minimum remaining amount of a normal secondary battery included in the AC output converter, and
A step to calculate the load sharing ratio based on the acquired minimum remaining amount ratio, and
A method for controlling a power supply system, comprising a step of adjusting the power supplied from the DC AC converter to the AC load according to a calculated load sharing ratio .

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