JP2003079069A - Backup power supply and power supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the structure of a power converter, and easily execute additional installation and exchange of parts. SOLUTION: An AC-DC converter is exchanged with a backup power supply at will, by making the dimensions and the connectors of the AC-DC converter and the backup power supply identical. Further, a function to charge a charge storage means on the backup power supply output side from the secondary battery when inserting the backup power supply and the one to collect current information and failure information of the AC-DC converter are added.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backup power supply and a power supply device, and more particularly to a backup power supply with a hot-swap function and an uninterruptible power supply suitable for backing up a power supply for converting power from a commercial AC power supply into DC power. The present invention relates to a power supply device having a function as a power supply device.

[0002]

2. Description of the Related Art Conventionally, an apparatus that operates by being connected to a commercial AC power supply, and in the event of a power failure of the commercial AC power supply, which causes damage such as loss of data, is externally connected. An uninterruptible power supply (UPS) is installed to take measures against blackouts. U installed outside
Generally, PS always uses an inverter power feeding system. This constant inverter power supply type UPS does not have a power source switching operation in the event of a power failure and has high power source stability, but has a low power conversion efficiency due to the large number of series stages of converters that pass between a commercial AC power source and a load. It is difficult to save energy. On the other hand, a backup power supply has been proposed in which a secondary battery and its charging / discharging circuit are mounted inside the device to eliminate the need for an external UPS. An example of this is the “UPS built-in power supply device” disclosed in Japanese Patent Laid-Open No. 9-322433.

[0003]

The configuration and operation of the conventional backup power supply device will be described with reference to FIGS. 19 and 20. First, in FIG. 19, the backup power supply device includes a commercial AC power supply 1, an information processing device 2, an AC-DC converter 60, a secondary battery 66, and a DC-DC converter 6.
3, a charging circuit 62, and a balance control unit 61. In this device, the commercial AC power supply 1 is connected to the AC-DC converter 60 and the charging circuit 62 inside the information processing device 2, and the secondary battery 66 and the DC-DC converter 63 are provided on the output side of the charging circuit 62. Input side is connected. The output side of the DC-DC converter 63 and AC-
The output side of the DC converter 60 is connected to the load 13. In addition, the AC-DC converter 60 and the DC-
The balance control circuit 61 is connected between the DC converters 63.

The operation of this circuit is shown in FIG. (A) is a steady state, and 90% of the electric power required by the load 13 is supplied from the commercial AC power supply 1 via the AC-DC converter 60. Further, the remaining 10% of electric power is supplied to the load 13 from the charging circuit 62 via the DC-DC converter 63. Further, the secondary battery 66 is charged via the charging circuit 62. On the other hand, (b) is the operation at the time of power failure, and the charging circuit 62 and the AC-DC converter 60 cannot operate because the commercial AC power supply 1 fails, but the secondary battery 66 causes the DC-
Through the DC converter 63, the load 13 is supplied with 100% of all the power required by the load.

In this system, the cost is high because three converters of the AC-DC converter 60, the DC-DC converter 63 and the charging circuit 62 are required.
There is a problem that the volume of the power supply unit is large.

Further, in this power feeding system, the charging circuit 62 is always operated and a constant voltage is applied to the secondary battery 66 in a steady state. However, when using a high energy density secondary battery such as a Ni-MH secondary battery or a Li-ion secondary battery, the charging circuit is stopped when the battery is in a fully charged state in order to prevent overcharging. However, in the above operating method, the charging circuit 6
When 2 is stopped, 10% from DC-DC converter 63
There is a problem that the power cannot be supplied for a minute. Further, in the conventional device, the AC-DC converter 60 and the DC
There is a problem in that there is no redundancy when the DC converter 63 and the secondary battery 66 fail or when they are replaced, and it is difficult to stop the system or to expand the system without stopping.

A first object of the present invention is to provide a power supply device capable of simplifying the structure of the power converter.

A second object of the present invention is to provide a backup power supply which can be easily added or replaced.

[0009]

In order to solve the above problems, the present invention provides a backup power supply for backing up an AC-DC converter for converting an AC received from a commercial AC power supply into a DC, which is the AC-DC. While the load connected to the DC output side of the converter is operating, the backup power supply is inserted into the device and connected to the load, and the backup power supply is connected from the load while the load is operating. We propose a backup power supply, which is characterized in that it can be disconnected from the device by disconnecting it. This backup power supply includes a bidirectional DC-DC converter, a secondary battery, a power failure detection means, and means for acquiring failure information of the plurality of AC-DC converters.

The bidirectional DC-DC converter has a higher voltage on the DC line side connected to the load than the terminal voltage of the secondary battery, and has a step-down chopper circuit configuration from the load side. While charging the secondary battery by, when detecting a power failure in the power failure detection means, or when the failure information is acquired, the step-down chopper circuit is used as a step-up chopper circuit to load from the secondary battery to the load. To discharge. At this time, it is also effective to provide current suppressing means on the secondary battery side of the step-down chopper circuit. The current suppressing means inserts current limiting switch means between the positive electrode side of the secondary battery and the inductor forming the step-down chopper circuit, and the anode is connected to the negative electrode side of the secondary battery, and It is desirable that the circuit is composed of a diode whose cathode is connected to the connection point of the current limiting switch means.

In the bidirectional DC-DC converter, the DC line side connected to the load has a lower voltage than the terminal voltage of the secondary battery, and has a step-up chopper circuit configuration as seen from the load side. This is a circuit for charging the secondary battery and discharging the secondary battery to the load by using the step-up chopper circuit as a step-down chopper circuit when a power failure or the AC-DC converter fails. Is also good.

Further, the secondary battery is divided into two systems, each secondary battery is connected to the bidirectional DC-DC converter via a battery switch means, and the secondary battery is provided for each system. A configuration in which it is inserted into and removed from is also useful.

The AC-DC converter and the AC-
A DC-DC converter connected to the DC output side of the DC converter, the AC-DC converter and the DC
A configuration may be adopted in which a converter integrated with a DC converter has a hot-swap function, an intermediate DC line of the converter is commonly connected to another converter, and at least one backup power supply is connected to the DC line. .

The AC-DC converter and the AC-
A DC-DC converter connected to the DC output side of the DC converter, the AC-DC converter and the DC
-A converter integrated with a DC converter is provided with a hot-swap function, the DC line in the middle of the two converters and the backup power supply are connected to different systems, and the backup power supply is connected to the DC line. A configuration having switching means is also effective.

Further, an AC switch means for controlling ON / OFF of a commercial AC power source is provided outside the apparatus, the ON / OFF of the AC switch means is controlled from the load, and the signal is sent from the load to the backup power source. Whether or not the backup power supply needs to be operated may be determined, or AC switch means and a server for controlling the on / off of the commercial AC power supply may be provided outside the device, and the server may control the on / off of the AC switch means. Alternatively, a signal sent from the server to the backup power supply via the load may determine whether or not the backup power supply needs to be operated.

It is also effective that the backup power supply has a peak cut function of supplying a current from the backup power supply to the load when the load current exceeds a predetermined value.

The backup power source includes a backflow detector,
Detecting that a current higher than the specified charging current flows in,
A means for disconnecting the backup power supply from the other AC-DC converter and the load may be provided.

It is also an effective means to have a plurality of backup power supplies and to have means for balancing the currents flowing from the backup power supplies to the load.

Further, the backup power source is provided with a circuit for calculating the upper limit value of the charging current, and the upper limit value of the charging current is calculated by monitoring the number of AC-DC converters currently operating and the load current. May be the above A
The load share current may be calculated from the current information of the current share control line and the charging current of the backup power supply of its own, while connecting the current share control line of the C-DC converter to the backup power supply.

When the backup power source is inserted, the switch means connected to the load is turned off,
The output side charge storage means inside the backup power supply is charged by the secondary battery inside the backup power supply, and when the voltage of the switch means becomes substantially the same as the voltage of the load side, the switch means is turned on. Turning it on increases reliability.

The AC-DC converter and the backup power supply may have a common connector or the AC-DC converter.
The DC converter and the backup power source may have the same dimensions, or the vertical dimension of the backup power source,
Two of the lateral and height dimensions may be the same as the AC-DC converter, and the other one may be an integral multiple.

Further, according to the present invention, a power supply circuit for converting an alternating current received from a commercial alternating current power supply into a direct current and a backup power supply for backing up the power supply circuit are provided, wherein the backup power supply is a secondary battery and the secondary battery. A DC-DC converter that converts the electric power of the battery into a direct current and outputs the direct current to a load, or converts the direct current power from the output of the power supply circuit into a direct current and outputs the direct current to the secondary battery; There is provided a power supply device including a control circuit for controlling the power supply.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing the configuration of a basic device of the present invention. In FIG. 1, 1 is a commercial AC power supply, 2 is an information processing device, 3a and 3b.
Is an AC-DC converter, 4a is a secondary battery, 5 is a bidirectional DC-DC converter, 6a and 6b are backup power supplies, 7 is a power failure detection circuit, 8a and 8b are smoothing capacitors,
9a, 9b are power MOSFETs, 10a, 10b, 1
0c and 10d are connectors, 11a, 11b, 11c and 1
1d is a connector, 12 is a DC-DC converter, 13 is a load, 14a, 14b, 14c, 14d are AC plugs,
15a, 15b, 15c and 15d are AC connectors, 16
Is a power factor correction circuit, 19a and 19b are current detection means, 2
0 and 21 are direct current lines, 22 is AC-DC converter current sharing signal line, 23 is backup power supply current sharing signal line, 24 is AC-DC converter operating state signal line, 4
6 is a control circuit, 47 is a control circuit, and 49 is a battery monitor.

Next, the connection of the configuration of FIG. 1 will be described.
The commercial AC power supply 1 is an AC plug 1 inside the information processing device 2.
4a, 14b, 14c, 14d, and the AC plug 14a is the AC connector 15 of the AC-DC converter 3a.
connected to a. Similarly, AC plug 14b is AC-DC
It is connected to the AC connector 15b of the converter 3b. A
Inside the C-DC converter 3a, the AC connector 15
a is connected to the power factor correction circuit 16, and the output of the power factor correction circuit 16 is input to the DC-DC converter 12. Also,
The output of the DC-DC converter 12 is the smoothing capacitor 8a.
Of the power MOSFET 9a, and the positive electrode side is connected to the source of the power MOSFET 9a. The source of the power MOSFET 9a is connected to the control circuit. The drain of the power MOSFET 9a is connected to the DC line 20 via the connector 10a and the connector 11a. The connector 10a and the connector 11a, the connector 10b and the connector 11b, the connector 10c and the connector 11c, and the connector 10d and the connector 11d are a pair of connectors, respectively. Power MOS
The gate of the FET 9a is connected to the control circuit 46. On the other hand, the negative side of the output of the DC-DC converter 12 is connected to the DC line 21 via the current detecting means 19a, the connector 10a, and the connector 11a. Also, DC-DC
The converter 12 is connected to the control circuit 46. The control circuit 46 is connected to the AC-DC converter current sharing signal line 22 and the AC-DC converter operating state signal line 24 via the connectors 10a and 11a. The AC-DC converters 3a and 3b have the same structure, the connectors 10a and 10b have the same shape, the connectors 10b and 11b have the same shape, and the connection between the AC-DC converter 3b and the connector 10b is the AC-DC converter 3a and the connector. 1
It is similar to the connection of 0a. The load 13 is connected to the DC lines 20 and 21.

Next, the AC connector 15c in the backup power supply 6a is connected to the AC plug 14c. The AC connector 15c is the power failure detection circuit 7 in the backup power supply 6a.
Connected to. The secondary battery 4 is in the backup power source 6a.
a, which is connected to the bidirectional DC-DC converter 5. The positive output of the bidirectional DC-DC converter 5 is connected to the source of the power MOSFET 9b via the smoothing capacitor 8b. The drain of the power MOSFET 9b is connected to the DC line 2 via the connector 10c and the connector 11c.
Connected to 0. The drain of the power MOSFET 9b is connected to the power failure detection circuit 7. Bidirectional DC-DC
The negative output of the converter 5 is connected to the DC line 21 via the smoothing capacitor 8b, the current detecting means 19b, the connector 10c and the connector 11c. The control circuit 47 includes a bidirectional DC-DC converter 5, a power failure detection circuit 7, and a power M.
In addition to being connected to the gate of the OSFET 9b, the current detecting means 19b, and the battery monitor 49, the connector 10c and the connector 1
AC-DC converter current sharing signal line 2 via 1c
2, backup power supply current share signal line 23, AC-D
It is connected to the C converter operating state signal line 24. The battery monitor 49 is connected to the secondary battery 4a. The backup power supply 6b has the same configuration as the backup power supply 6a, and is connected to the load 13 via the connector 10d and the connector 11d.

Next, the configuration of FIG. 2 will be described. 2 is shown in FIG.
3 is a diagram showing in detail an internal configuration of an AC-DC converter 3a in FIG. In FIG. 2, the same components as those in FIG. 1 have the same symbols. In addition, in FIG. 2, 17
Is an output control circuit, 18a is a backflow detection protection circuit, 25 is an operating state determination circuit, 26a is a comparator, 27a is a voltage error amplifier, 28a is a voltage command value, 29a is an adder, 3a.
Reference numeral 0a is a current error amplifier, 31a is a diode, 32a is a triangular wave generating means, 33 is a voltage reference value, 34 is a comparator, and 35a is a current detection circuit. Next, the configuration of FIG. 2 will be described. In FIG. 2, the AC connector 15a is connected to the DC-DC converter 12 via the power factor correction circuit 16, and the output of the DC-DC converter 12 is connected to the smoothing capacitor 8a and the power MOSFET 9a.
The drain of the power MOSFET 9a is connected to the DC line 20, and the power factor correction circuit 16, the DC-DC converter 12, and the negative side of the smoothing capacitor 8a are connected to the DC line 21. The current detection means 19a is the control circuit 4
6, the reverse current detection protection circuit 18a and the current detection circuit 35
connected to a. The reverse current detection protection circuit 18a is a power MO.
It is connected to the gate of the SFET 9a. In addition, AC-DC
The converter current sharing signal line 22 is connected to the cathode of the diode 31a and the current error amplifier 30a. The current detection circuit 35a is connected to the anode of the diode 31a and the current error amplifier 30a. The output of the current error amplifier 30a is connected to the adder 29a and the comparator 25. The voltage command value 28a is connected to the adder 29a. The output of the adder 29a is connected to the voltage error amplifier 27a. The source of the power MOSFET 9a is connected to the voltage error amplifier 27a. Voltage error amplifier 27a
Is connected to the comparator 26a. The output of the triangular wave generating means 32a is connected to the comparator 26a.
The output of the comparator 26a is the DC-DC converter 12
Entered in. The voltage reference value 33 is connected to the comparator 34. The output of the comparator 34 is connected to the AC-DC converter operating state signal line 24 via the resistor 41.

Next, the configuration of FIG. 3 will be described. FIG. 3 is a diagram showing in detail the internal configuration of the control circuit 47 of the backup power supply 6a in FIG. In FIG. 3, the same components as those in FIGS. 1 and 2 are denoted by the same symbols. 3, 26b is a comparator, 27b is a voltage error amplifier, 28b is a voltage command value, 29b is an adder, 30b is a current error amplifier, 31b is a diode, 32b is a triangular wave generating means, 35b is a current detection circuit, 36 Is current detection means,
37 is a charge upper limit value calculation circuit, 38 and 39 are operational amplifiers,
40 is a subtractor, 42 is a resistor, 43 is a positive / negative inverting means, 44
Is a gain, 45 is an integrator, 48 is voltage detecting means, 50 is a discharge control circuit, 51 is a charge control circuit, and 52 is an operation mode switching circuit. Details of the bidirectional DC-DC converter 5 will be described with reference to FIG.

Next, the connection of FIG. 3 will be described. The output of the power failure detection circuit 7 is the operation mode switching circuit 5 in the control circuit 47.
Entered in 2. The output of the battery monitor 49 is input to the operation mode switching circuit 52 and the charging control circuit 51. The output of the charge control circuit 51 is input to the operation mode switching circuit 52. The output of the operation mode switching circuit 52 is the reverse current detection protection circuit 18b and the bidirectional DC external to the control circuit 47.
-Input to the DC converter 5. The current detection means 19b and the gate of the power MOSFET 9b are connected to the backflow detection protection circuit. The charge upper limit value calculation circuit 37 is included in the control circuit 47, and the AC-DC converter current share signal line 22 is input to the operational amplifier 39 in the charge upper limit value calculation circuit 37. The operational amplifier 39 has a voltage follower configuration, and this output V2 is connected to the integrator 45. On the other hand, the AC-DC converter operating state signal line 24 is input to the operational amplifier 38 inside the charging upper limit value calculation circuit 37. A resistor 42, which is a feedback resistor, is connected to the operational amplifier 38, and the output V1 is input to the + input of the subtractor 40 and the gain 44 via the positive / negative inverting means 43. The output of the gain 44 is input to the integrator 45. The output of the integrator 45 is input to the-side of the subtractor 40. Current detecting means 19
The output of b is input to the minus side of the subtractor 40. Subtractor 40
Is output to the charging control circuit 51. On the other hand, the current detection means 36 inside the bidirectional DC-DC converter 5 is input to the charge control circuit 51 and the current detection circuit 35b inside the discharge control circuit 50. The backup power supply current share signal line 23 is connected to the cathode of the diode 31b and the current error amplifier 30b. In addition, the current detection circuit 3
5b is the anode of the diode 31b and the current error amplifier 3
0b. The output of the current error amplifier 30b is connected to the adder 29b. The voltage command value 2 is added to the adder 29b.
8b is connected. The output of the adder 29b is connected to the voltage error amplifier 27b. Further, the voltage detecting means 48 is connected to the voltage error amplifier 27b. Voltage error amplifier 27b
Is connected to the comparator 26b. The output of the triangular wave generating means 32b is connected to the comparator 26b.
The output of the comparator 26b is the operation mode switching circuit 5
Entered in 2.

Next, the configuration of FIG. 4 will be described. 4 is shown in FIG.
3 is a diagram showing in detail the configuration of a bidirectional DC-DC converter 5 inside the backup power supply 6a in FIG. In FIG. 4, the same components as those in FIGS. 1, 2 and 3 are denoted by the same symbols. In addition, in FIG. 4, 53 is a drive circuit and 54
a is a P-channel power MOSFET, 55a and 55b are power MOSFETs, 56 is an inductor, 57a is a smoothing capacitor, and 58 is a diode.

The connection of FIG. 4 will be described. In FIG. 4, both ends of the secondary battery 4a are connected to the smoothing capacitor 57a inside the bidirectional DC-DC converter 5. Here, the secondary battery 4a is an assembly in which a plurality of cells are connected in series. The positive electrode side of the smoothing capacitor 57a is a P channel power MOSF.
It is connected to the source of the ET 54a. P channel power M
The drain of the OSFET 54a is connected to the cathode of the diode 58 and the inductor 56. The anode of the diode 58 is connected to the negative electrode side of the smoothing capacitor 57a.
The inductor 56 is connected to the connection point between the drain of the power MOSFET 55a and the source of the power MOSFET 55b. The source of the power MOSFET 55a is connected to the anode of the diode 58 via the current detecting means 36. The drain of the power MOSFET 55b is connected to the positive electrode side of the smoothing capacitor 8b outside the bidirectional DC-DC converter 5 via the voltage detecting means 48. Power MOS
The source of the FET 55a is connected to the negative electrode side of the smoothing capacitor 8b. P-channel power MOSFET 54a, power MOSFET 55a and power MOSFET 55
The gate of b is connected to the drive circuit 53. Drive circuit 53
Is connected to the control circuit 47 outside the bidirectional DC-DC converter 5. The current detecting means 36 and the voltage detecting means 48 are connected to the control circuit 47.

Next, FIG. 5 shows the circuit of FIG.
When two AC-DC converters and one backup power supply are connected, that is, only the backup power supply 6b is not connected to the load 13, the AC-DC converters 3a, 3
FIG. 6B is a diagram showing an equivalent circuit of the charging upper limit value calculation circuit 37 inside the backup power supply 6a in the state where the backup power supply 6a is connected to the load 13. In addition, FIG.
Is the load 13 when the respective voltage values of the circuit of FIG.
It is a graph showing the load factor of the horizontal axis. next,
The operation of this embodiment will be described. In FIG. 1, AC-DC converters 3a and 3b and backup power supplies 6a and 6b are all connected by connectors on both the AC side and the DC side as shown in the drawing, and can be freely inserted into the information processing device 2 and connected to the load 13. The configuration is such that connection and disconnection from the information processing device 2 are possible. First,
The AC-DC converters 3a and 3b have exactly the same configuration. The AC-DC converter 3a will be described below.

In the operation of the AC-DC converter 3a, AC is input from the commercial AC power supply 1, and at this time, the power factor correction circuit 16 causes a current with few harmonics to flow. The output of the power factor correction circuit 16 is input to the DC-DC converter 12 and outputs a DC voltage to the smoothing capacitor 8a. This voltage is often used in, for example, a communication system or a server DC48.
It is desirable that the voltage is V, but it may be DC380V that is the output of the power factor correction circuit, or another voltage that is completely different.

The DC voltage of the smoothing capacitor 8a passes through the connectors 10a and 11a through the power MOSFET 9a, is applied between the DC line 20 and the DC line 21, and is supplied to the load 13. Next, referring to FIG.
The control of the DC converter 3a will be described. Control circuit 4
An output control circuit 17 and a backflow detection protection circuit 18 are provided inside the circuit 6.
a and the operation state determination circuit 25. Among them, the operation of the output control circuit 17 is as follows.

AC detected by the current detecting means 19a
-The output current of the DC converter 3a is the current detection circuit 35.
It is input to a and converted into a voltage value. Then, the output is applied to the anode side of the diode 31a. At this time,
If the voltage of the AC-DC converter current sharing signal line 22 is lower than the output voltage of the current detection circuit 35a,
The diode 31a becomes conductive and the voltage of the AC-DC converter current sharing signal line 22 becomes proportional to the output current of the AC-DC converter 3a. At this time, the output of the current error amplifier 30a is 0. However, when the voltage of the AC-DC converter current sharing signal line 22 is higher than the output voltage of the current detection circuit 35a, the diode 31a is non-conductive. At this time, a voltage proportional to the output current value of another AC-DC converter that outputs a larger current than the AC-DC converter 3a is applied to the AC-DC converter current sharing signal line 22. . Therefore, the output of the current error amplifier 30a becomes a value proportional to the difference between the voltage of the AC-DC converter current sharing signal line 22 and the current of the AC-DC converter 3a, and this error is added to the voltage command value 28a. Become. The voltage error amplifier 27a basically operates on the value of the voltage command value 28a and AC-D.
The output voltage feedback value of the C converter 3a is compared to amplify the error, and the comparator 26a outputs the triangular wave generating means 3
A pulse corresponding to the voltage error is generated by comparing with the output of 2a, and this pulse is generated by the DC-DC converter 12
By applying to the semiconductor switching element in
The output voltage of the C-DC converter 3a is set to the voltage command value 28a.
Of the current error amplifier 30
By adding the output of a to the voltage command value, AC-
The output voltage of the DC converter 3a is controlled so as to be slightly higher than before. As a result, AC-DC
The output current of the converter 3a rises and converges to a value that can be balanced with the currents of other AC-DC converters. In this way, the output control circuit 17 controls to balance the currents of the plurality of AC-DC converters.

Now, when the above current balance control is functioning normally, the output of the current error amplifier 30a is suppressed to a certain positive voltage value or less, and this value is the voltage reference in the operating state judging circuit 25. Since it is lower than the value 33,
The output of the comparator 34 becomes High, and the output voltage of the comparator 34 at this time is Vc. But D
When an abnormality such as a failure of the C-DC converter 12 or the power factor correction circuit 16 occurs, the current balance control is not normally performed and the output of the current error amplifier 30a becomes larger than the voltage reference value 33. At this time, the output of the comparator 34 changes from normal Vc to 0. Therefore, the operating states of the AC-DC converters 3a and 3b can be monitored by observing the output of the comparator 34.

Next, the operation of the backflow detection protection circuit 18a will be described. In the unlikely event that the DC-DC converter 12 fails or the smoothing capacitor 8a short-circuits, AC-DC
When the DC lines 20 and 21 are short-circuited inside the converter 3a, the current detecting means 19a and the reverse current detection protection circuit 18a detect the reverse current flowing from the DC-DC converter 12 toward the direct current line 21, and the power MOSFET 9a. Turn off promptly. By this operation, the AC-DC converter 3a is disconnected from the load 13. Current is supplied to the load 13 from the AC-DC converter 3b, and power supply is not interrupted instantaneously.

In the embodiment of the present invention, the load 1 is monitored by monitoring the AC-DC converter current sharing signal line 22 and the AC-DC converter operating state signal line 24, which is the output of the comparator 34, on the side of the backup power supplies 6a and 6b.
A method of grasping the current flowing in the No. 3 will be described later with reference to FIG.

Next, the operation of FIG. 3 will be described. FIG. 3 shows FIG.
FIG. 4 is a diagram showing in detail an internal configuration of a control circuit 47 of the backup power supply 6a in FIG.

First, the charge upper limit value calculation circuit 3 in FIG.
The operation of No. 7 will be described with reference to FIGS. 3 and 5. FIG. 5 shows AC
-DC converters 3a and 3b and backup power supply 6a are connected to load 13, and backup power supply 6b is load 13
It is an equivalent circuit when not connected to. That is,
The resistor 41 of the AC-DC converter 3a and the resistor 41 of the AC-DC converter 3b are in a parallel connection, and the backup 6a is provided via the AC-DC converter operating state signal line 24.
Operational amplifier 38 of the charge upper limit value calculation circuit 37 inside the
Will be connected to the negative terminal of. Operational amplifier 3
8 has a feedback resistor 42, and the output voltage is V1. At this time, if both the AC-DC converters 3a and 3b are in a normal state, V1 becomes V1 = −2 · Vc (when two units are normal) (1). V1 when one of the AC-DC converters fails is V1 = -Vc (when one fails) (2).

On the other hand, the voltage of the AC-DC converter current sharing signal line 22 is a voltage proportional to the output current of the one of the AC-DC converters 3a and 3b which produces the most current, and is in a steady state. Then multiple AC
-The DC converter currents are balanced. Therefore, this voltage is set to V2 and 100% can be obtained with one AC-DC converter.
If V2 is set to Vc when a load is applied,
The graph of FIG. 6 is obtained. Here, backup power source 6
The charging current that a is currently receiving from the AC-DC converter can be detected at 19b. Therefore, the charging current is detected at the same level as the load, and the charging current ratio for charging the same capacity as the 100% load is CHG (%). When CHG = 100%, Vc
To the voltage.

At this time, the load factor including the charging current is set to Load.
(%), V2 is represented by the following formula.

V2 = 0.5 · Vc · Load (when two units are healthy) (3) V2 = Vc · Load (when one unit fails) (4) Now, V1 passes through the positive / negative inversion means 43 and its output is V
When it is set to 4, V4 = -V1 = 2Vc (when two units are healthy) (5) V4 = -V1 = Vc (when one unit fails) (6). V4 is multiplied by 1 / Vc via the gain 44, and integrated by the integrator 45 with V2. Therefore, assuming that the output of the integrator is V5, V5 = V2 · 2 (when two units are healthy) (7) V5 = V2 (when one unit fails) (8) Therefore, V3 is V3 = V4-V5-(-Vc.CHG) = 2.Vc-2.V2 + Vc.CHG = (2-Load + CHG) .Vc (when two units are healthy) (9) V3 = V4-V5- ( −Vc · CHG) = Vc−V2 + Vc · CHG = (1-Load + CHG) · Vc (when one unit fails) (10). Therefore, the graph of V3 in FIG. 6 is as illustrated when two units are in good condition (solid line) and one unit is in failure (broken line).

In FIG. 3, the charging upper limit value V3 output from the charging upper limit value calculating circuit 37 to the charging control circuit 51 is the AC currently operating as shown in the above equations (9) and (10).
-It is a value proportional to the remaining capacity of the DC converter capacity, which is obtained by subtracting the power corresponding to the current charging current from the power corresponding to the load current. Therefore, by using this upper limit value V3 as a command value for the charging operation in the backup power supply 6a, it becomes possible to perform rapid charging using the capacity of the AC-DC converter up to the rated value.

The operation of the charging circuit is as follows.
V3 calculated by the charge upper limit value calculation circuit 37 is input to the charge control circuit 51. Further, the battery monitor 49 calculates the remaining battery capacity from the battery voltage, current and temperature, and inputs it to the charge control circuit 51. Therefore, the charging control circuit 51 sets a charging current command value according to the remaining battery capacity with V3 as the upper limit, and this command value is set to the operation mode switching circuit 5
Output to 2. In the operation mode switching circuit 52, the operation is switched by the output of the power failure detection circuit 7, but when the power failure detection circuit 7 does not detect the power failure, the charging or standby state is selected. In the charging state, the bidirectional DC-DC converter 5 is operated, and a pulse according to the charging current command value is input to the bidirectional DC-DC converter 5.

In this system, since V3 decreases as the load 13 increases, charging does not exceed the capacity of the AC-DC converter, and even if one AC-DC converter fails, V3 can be quickly changed to the solid line. From the above to the broken line, the charging current is suppressed, the fear of overloading the AC-DC converter is avoided, and the power supply to the load 13 is not hindered.

Next, the backflow detection function in the backup power supply will be described. In Figure 1, just in case
-If the DC lines 20 and 21 are short-circuited inside the backup power supply 6a due to a failure of the DC converter 5 or a short circuit of the smoothing capacitor 8b, both the current detection means 19b and the reverse current detection protection circuit 18b of FIG. A reverse current flowing from the direct current DC-DC converter 5 in the direction of the DC line 21, that is, a current in the charging direction is detected. In the charging state, when the value becomes larger than V3 corresponding to the charging current command value, the power MOSF
ET9b is turned off immediately. In the standby state or the discharge state, the power MOSFET is detected at the time when the backflow is detected.
Turn off T9b. By this operation, backup power supply 6
a is disconnected from the load 13.

Next, the operation of the discharge control circuit of the backup power supply will be described. The backup power source starts its operation when the power failure detection circuit 7 in FIG. 1 detects a power failure of the commercial AC power source 1 or a voltage drop between the DC lines 20 and 21. First, the power failure detection circuit 7 is the AC plug 1
4c and AC connector 15c are connected to the commercial AC power supply 1, and it detects that the commercial AC power supply 1 is out of a predetermined range due to a momentary power failure, a drop, a frequency abnormality, or the like. On the other hand, the power failure detection circuit 7 is the DC line 2
It is also connected between 0 and the DC line 21, and an abnormality is detected when this voltage exceeds a predetermined range, for example, a value exceeding ± 10% of the rated voltage.

When the power failure detection circuit 7 detects a power failure or abnormality, the operation mode switching circuit 52 shown in FIG.
Is switched to discharge control. At this time, the drive signal input from the discharge control circuit 50 to the operation mode switching circuit 52 is output to the bidirectional DC-DC converter 5. Of course, the drive signal from the charge control circuit 51 is cut off by the operation mode switching circuit 52, and the bidirectional DC-DC converter 5 does not perform the charging operation but performs the discharging operation.

In this discharge operation, one backup power supply may perform the discharge operation, and a plurality of backup power supplies may perform the discharge operation simultaneously. The operation will be described for each case.

First, in the case of one backup power supply, at this time, in the discharge control circuit 50 of FIG. 3, the backup power supply current share signal line 23 is not connected to another backup power supply, and 23 is in an open state. It is in.
Therefore, the input of the current error amplifier 30b has the same potential, and the output of the current error amplifier 30b is 0. Therefore,
In the discharge control circuit 50, substantially only the voltage error amplification control is performed. In this control, the output of the voltage detection means 48 on the output side of the bidirectional DC-DC converter 5 is input to the voltage error amplifier 27b as a feedback voltage and compared with the voltage command value 28b. Then, the error is amplified and compared with the triangular wave generating means 32b by the comparator 26b,
It outputs a pulse train according to the voltage error, passes through the operation mode switching circuit 52, and drives the switching element inside the bidirectional DC-DC converter 5. In addition,
The internal operation of the bidirectional DC-DC converter 5 will be described later with reference to FIG.

Next, when there are a plurality of backup power supplies, the current error amplification section is different from the case where there is one. The output current of the backup power supply 6a detected by the current detection means 36 is input to the current detection circuit 35b and converted into a voltage value. Then, the output is applied to the anode side of the diode 31b. At this time, if the voltage of the backup power supply current share signal line 23 is lower than the output voltage of the current detection circuit 35b, the diode 31b becomes conductive and the backup power supply current share signal line 23 is proportional to the output current of the backup power supply 6a. It becomes the voltage. At this time,
The output of the current error amplifier 30b is 0. However, when the voltage of the backup power supply current share signal line 23 is higher than the output voltage of the current detection circuit 35b, the diode 3
1b is non-conductive. At this time, a voltage proportional to the output current value of another backup power supply that outputs a larger current than the backup power supply 6a is applied to the backup power supply current share signal line 23. Therefore,
The output of the current error amplifier 30b becomes a value proportional to the difference between the voltage of the backup power supply current share signal line 23 and the current of the backup power supply 6a, and this error is the voltage command value 28b.
Will be added to. The voltage error amplifier 27b basically has the voltage command value 28b and the backup power supply 6a.
Of the output voltage feedback value is compared to amplify the error, and the comparator 26b compares the output voltage feedback value with the output of the triangular wave generating means 32b to generate a pulse corresponding to the voltage error, and the pulse is generated in the bidirectional DC-DC converter 5. By applying the voltage to the semiconductor switching element, the output voltage of the backup power supply 6a matches the output of the voltage command value 28b, but the output of the current error amplifier 30b is added to the voltage command value, so that the backup power supply 6a The output voltage of is controlled so as to increase slightly. As a result, the output current of the backup power supply 6a rises and converges to a value that can be balanced with the currents of other backup power supplies. In this way, it becomes possible to perform control to balance the currents of the plurality of backup power supplies.

In the present embodiment, since a voltage proportional to the current of the backup power supply which is currently outputting the largest current is applied to the backup power supply current share signal line 23, a plurality of backup power supplies are backed up. Among the power supplies, the backup power supply whose secondary battery has reached the end of discharge and the backup power supply that should have failed should be automatically disconnected from the current balance control of multiple units to suppress load voltage fluctuations. . Therefore, even if one of the backup power supplies fails while being discharged, the load will not be affected even if the backup power supplies are removed or inserted from the device in a live state.

Next, the operation of the circuit shown in FIG. 4 will be described. FIG. 4 shows, as an example of the bidirectional DC-DC converter 5, a DC-DC converter that performs a step-up chopper operation during discharging and a step-down chopper operation during charging.

First, the charging operation will be described. At the time of charging, the P-channel power MOSFET 54 shown in FIG.
After turning on a, the power MOSFET 55b is switched to charge the secondary battery 4a. A predetermined voltage, for example 48V, is applied between the smoothing capacitors 8b during charging, and the terminal voltage of the secondary battery 4a is set to be lower than that even when fully charged. When the power MOSFET 55b is turned on, the smoothing capacitor 8b moves to the power MOSFET 55b.
b, inductor 56, P-channel power MOSFET 5
4a, the smoothing capacitor 57a and the secondary battery 4a form a loop, and the smoothing capacitor 57a and the secondary battery 4a are formed.
To charge. When the power MOSFET 55b is turned off,
The excitation energy stored in the inductor 56 is the P-channel power MOSFET 54a, the smoothing capacitor 57a,
The current flows through the body diode of the power MOSFET 55a and circulates. By controlling the on-time ratio of the power MOSFET 55b, constant current charging control can be performed so that the average current value of the inductor 56 matches the charging current command value of the secondary battery 4a. The smoothing capacitor 57a is a ripple absorbing capacitor that is inserted to suppress deterioration caused by a high-frequency ripple current flowing through the secondary battery 4a. Further, the charging current command value is the upper limit value of the charging current calculated by the charging upper limit value calculation circuit 37 as described above,
It is determined by the charge control circuit 51 by judging from the state of the secondary battery 4a input from the battery monitor 49. Further, during charging, so-called synchronous rectification may be performed, in which the power MOSFET 55a is turned on when the power MOSFET 55b is turned off.

Next, the discharge operation will be described. When the P-channel power MOSFET 54a is kept on and the power MOSFET 55a is turned on, a short circuit current flows from the secondary battery 4a through the inductor 56 and the power MOSFET 55a. When the power MOSFET 55a is turned off,
The excitation energy stored in the inductor 56 becomes a current and flows through the route of the body diode of the power MOSFET 55b, the smoothing capacitor 8b, and the secondary battery 4a, and charges the smoothing capacitor 8b. The discharge control circuit 50 performs feedback control so that this voltage becomes a predetermined voltage. Even during this discharge, the power MOSF
In order to reduce the loss due to the current flowing through the body diode of the ET55b, power MOSFET is used during this period.
It is also possible to turn on 55b.

Next, the operation at the time of overcurrent will be described. In the unlikely event that the load 13 exceeds a preset overcurrent value due to a failure such as a short circuit, the following current drooping control is performed.

In this case, the current drooping control is performed.
Specifically, by the drive circuit 53, the P channel power MO
The SFET 54a is turned on and off. When the P-channel power MOSFET 54a is turned on, current flows from the secondary battery 4a as described above. However, when the P-channel power MOSFET 54a is turned off, the current flowing in the inductor 56 circulates in the diode 58 and recharges the secondary battery. 4a is separated. Therefore, this P-channel power MOSF
By chopping the ET 54a, the output voltage can be lowered and the output current can be limited.

In this embodiment, a conventional boost type D
Even when the load is short-circuited which cannot be prevented by the C-DC converter, it is possible to avoid damage to the secondary battery 4a or the backup power supply by performing the current drooping control by the chopping operation.

Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 7 is a circuit diagram of FIG. 1, in which three AC-DC converters and two backup power supplies are connected to the load 13, the charge upper limit value calculation circuit 37 inside the backup power supplies 6a and 6b, the AC-DC converters 3a, 3b, and It is a figure showing connection of AC-DC converter 3c of exactly the same form.

FIG. 8 is a graph showing changes in each voltage with respect to the load when three AC-DC converters are healthy and when one of them fails in FIG. Next, the operation of this embodiment will be described.

First, in FIG. 7, it is assumed that all the AC-DC converters are operating normally. At this time, Vc is applied to all the resistors 41 of the AC-DC converters 3a, 3b and 3c. This resistor 41 is A
It is connected to the C-DC converter operating state signal line 24 and input in parallel to the operational amplifiers 38 of the backup power supplies 6a and 6b. If the current flowing through the resistor 41 is I, then I = Vc / R1 (11), so the current I1 flowing through the resistor 42 of the backup power supplies 6a and 6b is I1 = 3 · I / 2 = 1.5Vc / R1 (12) , V1 = -1.5 · Vc (13) (when 3 units are healthy). If one of the AC-DC converters fails, I1 = 2 · I / 2 = Vc / R1 (14), and as a result, V1 is V1 = −Vc (15) (when one unit fails). Becomes Therefore, V4 = 1.5 · Vc (16) (when three units are healthy) V4 = Vc (17) (when one unit fails) V5 = 1.5 · V2 (18) (when three units are healthy) V5 = V2 (19) (1) (At the time of machine failure). Therefore, assuming that the charging current is 0, V3 becomes V3 = 1.5 (Vc-V2) (16) (when three units are healthy) V3 = Vc-V2 (17) (when one unit fails), and V3 in FIG. Is calculated. This value is used as the charging current upper limit value to limit the charging current of each backup power supply.

Next, a third embodiment of the present invention will be described with reference to FIG. In FIG. 9, the same symbols are assigned to the same components as those in the other drawings. Other 1
1e is a connector. FIG. 9 shows a power supply section of the apparatus, in which connectors 11a to 11e are regularly arranged on the apparatus side. Then, the AC-DC converter 3a, AC-
DC converter 3b has connectors 11a and 11b, respectively.
Inserted in. On the other hand, the backup power source 6a and the backup power source 6b are connected to the connectors 11c and 11d, respectively. The AC-DC converter and the backup power supply have the same size, and the connector 11 can be commonly used. The connector 11e is a spare connector and is used when the device load increases. In this case, AC-DC
If the same AC-DC converter as the converters 3a and 3b is connected to the connector 11e, the load capacity of the device increases.

There is a case where it is desired to increase the power failure compensation time beyond the standard set value, instead of increasing the load on the device. In this case, the backup power supplies 6a, 6 are connected to the connector 11e.
By connecting the same backup power supply as in b, it is possible to increase the power failure compensation time by about 1.5 times when the load capacity is the same.

In the present embodiment, as described above, the AC-DC converter and the backup power supply can be flexibly increased or replaced for each unit according to the demand of the load. It can be said that it is superior in flexibility and scalability.

Next, a fourth embodiment of the present invention will be described with reference to FIG. 10, the same symbols are given to the same components as those in the other drawings. Similar to FIG. 9, FIG. 10 shows the power supply unit of the apparatus, in which connectors 11a to 11e are regularly arranged on the apparatus side. Then, the AC-DC converter 3a and the AC-DC converter 3b are inserted into the connectors 11a and 11b, respectively. On the other hand, the backup power source 6a and the backup power source 6b are connected to the connectors 11c and 11d, respectively. The connector 11e is a spare connector. 10 is different from FIG. 9 in that the horizontal width of the backup power supplies 6a and 6b is twice that of the AC-DC converter. By doubling the size of the backup power source, it is possible to mount the backup power source without any gaps with the AC-DC converter. Further, as compared with the backup power supply shown in FIG. 9, a secondary battery having a capacity twice or more can be mounted. Furthermore, since it is compatible with the backup power supply shown in FIG. 9, the size of the backup power supply can be selected according to the load.

A fifth embodiment of the present invention will be described with reference to FIGS. 1 and 11. FIG. 11 is a diagram showing the procedure for starting up the backup power supply, showing the capacitor voltage Vcout, the gate voltage of the power MOSFET 9b, and the change over time in the operation mode of the backup power supply.

In this embodiment, a procedure for starting up the backup power supply 6a inserted in the apparatus will be described. First, in FIG. 1, when the backup power supply 6a is incorporated in the apparatus, the connector 10c is physically connected to the connector 11c.
Insert into c and fix. Next, connect the AC plug 14c to AC
Connect to the connector 15c. At this time, the backup power supply is not operating yet, so the power MOS of FIG.
The FET 9b is off. This state is the stopped state in FIG. Next, the discharge circuit is operated from the secondary battery 4a to charge the smoothing capacitor 8b. As a result, the smoothing capacitor 8b is charged to a predetermined voltage of 48V. Next, the gate voltage of the power MOSFET 9b is gradually increased as shown in the figure, and the power MOSFET
Turn on 9b very slowly. At this time, a method of flowing a minute current into the gate of the power MOSFET 9b by a current source is effective. Power MOSFET 9b
Is completely turned on, the charging mode is entered, and the backup power source charges the secondary battery 4a to prepare for a power failure.

According to the present embodiment, when the backup power supply is inserted, the initial charging current of the smoothing capacitor is not taken from the load side but is charged in advance from the secondary battery of the backup power supply, so that the load voltage fluctuation at the time of insertion is prevented. It is possible to suppress.

Next, a sixth embodiment of the present invention will be described with reference to FIG. FIG. 12 is a circuit diagram showing one form of the bidirectional DC-DC converter 5 in the present invention. In FIG. 12, the same symbols are given to the same components as those in the other drawings. Besides, in FIG. 12, 55c and 55d are power MOSFETs.

In FIG. 12, the secondary battery 4a is a bidirectional D
It is connected to both ends of the smoothing capacitor 57a inside the C-DC converter 5. Both ends of the smoothing capacitor 57a are connected to series-connected power MOSFETs 55d and 55c. Power MOSFET 55c and power MOSFET
The midpoint of 55d is connected to the inductor 56. The inductor 56 is connected to the smoothing capacitor 8b outside the bidirectional DC-DC converter 5, and the voltage detecting means 48 is connected to this connection point.
Are connected. Further, the negative electrode side of the smoothing capacitor 8b and the negative electrode side of the power MOSFET 55c are connected, and the current detection means 36 is connected therebetween. Further, the drive circuit 53 is connected to the gates of the power MOSFETs 55c and 55d. Control circuit 47 outside the bidirectional DC-DC converter 5
The current detection means 36, the voltage detection means 48, the drive circuit 53
Are connected respectively.

Next, the operation of FIG. 12 will be described. First, as a condition, the terminal voltage of the secondary battery 4a is set higher than Vcout even at the end of discharge. Then, at the time of charging, the drive circuit 53 outputs a pulse signal for turning on / off the power MOSFET 55c. Power MOSFET 55
When c is turned on, the smoothing capacitor 8b moves to the inductor 5
A current flows through 6. When the power MOSFET 55c is turned off, the excitation energy stored in the inductor 56 becomes a current and passes through the body diode of the power MOSFET 55d to pass through the smoothing capacitor 57a and the secondary battery 4a.
To charge. By repeating this operation, the average value of the current flowing through the inductor 56 is appropriately controlled and the secondary battery 4a is charged.

On the other hand, when a power failure occurs, a discharge signal is sent from the control circuit 47 through the drive circuit. At this time,
The power MOSFET 55d turns on and off to turn on the secondary battery 4a.
Then, the output voltage Vcout is controlled to be constant. When the power MOSFET 55d is turned on, a discharge current flows from the secondary battery 4a to the inductor 56 and the smoothing capacitor 8b through the power MOSFET 55d. When the power MOSFET 55d is turned off, the current flowing through the inductor 56 circulates through the body diode of the power MOSFET 55c. By repeating this operation and controlling the on-time ratio of the power MOSFET 55d, the voltage Vcout of the smoothing capacitor 8b can be controlled to be constant. Further, in this case, even when the load is short-circuited, the current drooping control can be performed only by controlling the on-time ratio of the power MOSFET 55d. It is also possible to perform synchronous rectification for reducing the loss of the body diode by turning on the power MOSFET corresponding to the period in which the body diode of the power MOSFET flows in the above operation.

Next, a seventh embodiment of the present invention will be described with reference to FIG. FIG. 13 is a diagram showing one configuration of the bidirectional DC-DC converter 5 in the backup power supply, and shows a power supply having two-system secondary batteries. The same symbols are attached to the same components as those in the other drawings. In addition, in FIG. 13, 4b is a secondary battery and 57b.
Is a smoothing capacitor, and 54b, 54c and 54d are P-channel power MOSFETs. Since FIG. 13 is based on FIG. 4, only portions different from the first embodiment in connection relations and operations will be described below.

First, as for the connection relationship, in contrast to FIG. 4, in FIG. 13, the P-channel power MOSFET is located between the source of the P-channel power MOSFET 54a and the smoothing capacitor 57a.
54b is inserted. The direction is P channel power M
Source of OSFET 54a and P-channel power MOSF
This is the direction in which the source of the ET 54d is connected. Further, the secondary battery 4b and the smoothing capacitor 57b are connected, and the negative electrode side of the secondary battery 4a is connected. Between the positive electrode side of the smoothing capacitor 57b and the cathode of the diode 58, the sources of the P-channel power MOSFETs 54c and 54d are connected to each other and are connected in anti-series.

Next, the operation will be described. When charging,
Basically, P-channel power MOSFETs 54a, 54
b, 54c, 54d are all turned on, and power M
By controlling the current flowing through the inductor 56 by controlling the ON-time ratio of the OSFET 55b, the current is shunted equally to the secondary batteries 4a and 4b to be charged. Here, assuming that one of the plurality of battery cells forming the secondary battery 4a has caused a short circuit failure, the voltage of the secondary battery 4a is lower than the voltage of the secondary battery 4b, and the charging current is reduced. Is not uniform, and a cross current is generated between the secondary battery 4b and the secondary battery 4a. Therefore, at this time, the battery monitor 49 detects the voltage drop of the secondary battery 4a, and the P-channel power MOSFET 54a,
Turn off 54b. As a result, the secondary battery 4a is disconnected from the system, and the backup power source 6a uses only the secondary battery 4b having a half capacity to perform charging and discharging. This can be regarded as the degenerate operation of the backup power supply.

At this time, since the secondary battery 4a is completely separated from the system by the P-channel power MOSFETs 54a and 54b, the secondary battery 4a is kept healthy by the secondary battery 4b while maintaining the power failure compensation function of the backup power source. It is possible to replace only the battery 4a with a new secondary battery.

The present embodiment is characterized in that the secondary battery is divided into two series, which makes it possible not only to operate in the degenerate mode in the case of a short circuit failure of the secondary battery cell, but also to perform non-stop operation. It is possible to replace only the secondary battery that has failed.

Next, an eighth embodiment of the present invention will be described with reference to FIG. FIG. 14 is a configuration diagram when a backup power supply with a hot-swap function is applied to an AC-DC converter having a multi-output converter configuration. 14, the same symbols are given to the same constituent elements as those in the other figures. In addition, in FIG. 14, 59a, 59
Reference numerals b, 59c and 59d denote DC output lines, and 67 denotes a multi-output DC-DC converter. The connection of FIG. 14 is based on that of FIG. Differences between FIG. 14 and FIG. 1 will be described below. In FIG. 14, a multi-output DC-DC converter 67 is connected between the drain of the power MOSFET 9a and the negative electrode side of the smoothing capacitor 8a. The output of the multi-output DC-DC converter 67 is the connector 10a,
It is connected to the load 13 via the connector 11a, of which + 12V is the DC output line 59a, + 5V is the DC output line 59b, and + 3.3V is the DC output line 59.
c, the DC output line 59d is a ground line. A
The C-DC converter 3b also has the same configuration as the AC-DC converter 3a, and is similarly connected to the load 13 via the connectors 10b and 11b.

The operation of FIG. 14 will be described below. 48 which is the input voltage of the multi-output DC-DC converter 67
V is connected to other AC-DC converters and backup power supplies 6a and 6b. These multiple AC-D
C converter is 12V, 5V,
At each 3.3V, the current output by each AC-DC converter is balanced. This control is shown in Figure 2.
This is the same as the control described in.

When the commercial AC power supply 1 fails, the power failure detection circuit 7 inside the backup power supply detects the power failure and supplies 48V from the backup power supply side to maintain the input voltage of the multi-output DC-DC converter. As a result, the output of the multi-output DC-DC converter is 1
2V, 5V and 3.3V are not affected by power failure and load 1
It is possible to continue supplying to 3.

Next, a ninth embodiment of the present invention will be described with reference to FIG. FIG. 15 shows a configuration in which a power supply switch is provided outside the information processing apparatus and operation is performed from a load. In FIG. 15, the same symbols are given to the same constituent elements as those in the other figures. Besides, in FIG. 15, reference numeral 64 is a switch means.

In FIG. 15, the switch means 64 is provided outside the information processing apparatus 2 and is inserted between the commercial AC power supply 1 and the information processing apparatus 2.

Next, the operation will be described. First, when activating the information processing device 2, the switch means 64 is manually operated. Thereby, the AC-DC converters 3a, 3
Power is supplied to the load 13 via b, and the load 13 starts operating. Next, when turning off the load 13, the load 13 is shut down by operating the switch means on the load 13 side. At this time, the operating state of the load 13 is transmitted to the AC-DC converters 3a and 3b and the backup power supply 6a, and when a power failure occurs before shutdown, the backup power supply 6a operates to supply power to the load 13. . When the shutdown of the load 13 is completed, the signal output from the load 13 to the AC-DC converters 3a and 3b and the backup power supply 6a changes. Then, the off signal is output from the load 13 to the switch means 64, and the power supply to the load 13 is cut off. Since the backup power source 6a knows the state of the load 13, it does not operate even if the switch means 64 is turned off at this time to enter the power failure state.

On the other hand, when the switch means 64 is inadvertently turned off, the backup power supply operates to protect the system, which is also effective as a human error prevention measure.

As described above, in the present embodiment, the operation of the backup power supply /
Inactivity can be determined.

Next, a tenth embodiment of the present invention will be described with reference to FIG. 16 is similar to FIG. 15, a power switch is provided outside the information processing device,
The configuration when operating from the load is shown. Figure 1
6, the same symbols are given to the same components as those in the other figures. In addition, in FIG. 16, reference numeral 65 is a server.
The present embodiment differs from FIG. 15 in that a server 65 is provided outside, the server 65 and the load 13 are connected, and the server 65 and the switch means 64 are connected.

Next, the operation will be described. In this example,
It is the server 65 that sends the operation / stop command to the load 13. First, when activating the information processing device 2, the switch means 64 is operated from the server 65. This makes AC
-Power is supplied to the load 13 via the DC converters 3a and 3b, and the load 13 starts operating. Next, load 13
When turning off, the load 13 is shut down by sending a shutdown signal from the server to the load 13. At this time, the operating state of the load 13 is AC-D.
It is transmitted to the C converters 3a and 3b and the backup power source 6a, and when a power failure occurs before shutdown, the backup power source 6a operates to supply power to the load 13. When the shutdown of the load 13 is completed, the signal output from the load 13 to the AC-DC converters 3a and 3b and the backup power supply 6a changes. Then, after the server 65 recognizes the shutdown of the load 13, the server 65 is instructed to the switch means 64.
Outputs an off signal from the power supply to disconnect the power supply to the load 13.
Since the backup power source 6a knows the state of the load 13, it does not operate even if the switch means 64 is turned off at this time to enter the power failure state.

As described above, also in this embodiment, the operation of the backup power supply /
Inactivity can be determined.

Next, an eleventh embodiment of the present invention will be described with reference to FIG. FIG. 17 shows the relationship between the power source and the load of the information processing apparatus, and is a diagram showing the direction of power supply and demand depending on the state of the load and the power source. In FIG. 17, the same symbols are given to the same constituent elements as those in the other figures. The connection relationship of FIG. 17 is the same as that of FIG. Note that the power supply / load connection relationship in FIG. 17 shows only the power supply and demand line, so the backup power supplies 6 a and 6 b are not connected to the commercial AC power supply 1.

FIG. 17A shows the supply and demand of electric power when the load is light, in which the commercial AC power source 1 supplies power to the load 13 through the AC-DC converters 3a and 3b, while the AC-
From the DC converters 3a and 3b to the backup power source 6a,
The secondary battery in 6b is charged.

Next, FIG. 17B shows the supply and demand of electric power at the time of peak load. At this time, the commercial AC power sources 1 to A
Electric power is supplied to the load 13 through the C-DC converters 3a and 3b, and discharged from the backup power supplies 6a and 6b. This operation is called peak cut. As a result, the AC-DC converter 3a during peak load,
The load of 3b is lighter than that when the peak cut operation is not performed. For this reason, it is possible to lower the rated power of the AC-DC converter from the power at the peak load for the load in which the degree of appearance of the peak load is determined. As a result, the capacity of the AC-DC converter can be reduced, and the volume and cost can be reduced.

Further, (c) shows an operation at the time of a power failure or an AC-DC converter failure, and this operation is the same as the content described in the first embodiment of the present invention. That is, when the commercial AC power supply 1 fails,
The backup power supplies 6a and 6b can discharge the load 13 to supply power. Further, the AC-DC converter has a multiplexing structure, and for example, even if only the AC-DC converter 3a fails, the AC-DC converter 3b.
The load 13 is maintained by supplying power from the AC-D
Even if the C converter 3b also fails, the power to the load 13 can be maintained by discharging the backup power supplies 6a and 6b.

Further, in the present embodiment, during the peak load of (b), the peak current component is compensated only from the backup power supply 6a, the backup power supply 6b is stopped, and at the time of the power failure of (c), the backup power supply 6a,
It is also possible to supply electric power from 6b. In the peak cut operation, the states of (a) and (b) are frequently repeated according to the state of the load, so by any chance, the peak load may continue to some extent and the secondary battery remaining amount inside the backup power supply 6a may decrease. If there is a power failure while the power is off, the system will not work unless sufficient power backup time is maintained. However, in this way, the peak cut is always shared only by the AC-DC converter 6a and the backup power supply 6b is put on standby for a power failure, so that this problem can be solved.

Next, a twelfth embodiment of the present invention will be described with reference to FIG. FIG. 18 shows AC-
It is a figure showing the connection form of two DC converters and two backup power supplies, and is based on FIG. 14 explained in the eighth embodiment of the present invention. In FIG. 18, the same symbols are given to the same components as in the other drawings. In addition, in FIG. 18, 68 is a DC line, 69a, 69
b, 70a, 70b are switching means. The connection relationship of FIG. 18 is almost the same as that of FIG. 14, but there are two DC systems corresponding to the DC line 20 of FIG.
0 and the DC line 68 are in parallel. In addition, AC-
In the DC converter 3a, the switching means 69a is connected to the drain of the power MOSFET 9a and selectively connected to the DC lines 20 and 68. Similarly, also in the AC-DC converter 3b, the switching means 69b has the DC line 20.
And 68 are selectively connected. On the other hand, backup power supply 6a
In, the switching means 70a is selectively connected to the DC line 20 and the DC line 68. Also, backup power supply 6
In b, the switching means 70b is selectively connected to the DC line 20 and the DC line 68.

Next, the operation of the present invention will be described. AC-DC
The switching means 69a of the converter 3a is connected to the DC line 20. Also, the switching means 6 of the AC-DC converter 3b
9b is set to be connected to the DC line 68.
On the other hand, the switching means of the backup power source 6a is the DC line 2
0, and the switching means of the backup power supply 6b is set to be connected to the DC line 68.

Therefore, the DC line 20 is connected to the AC-DC converter 3a and the backup power source 6a, and the DC line 68 different from this is connected to the AC-DC converter 3a.
b and the backup power supply 3b are connected.

In the unlikely event that the DC line 20 is the DC line 21
AC-DC converter 3
a is in a failure state and cannot output. However, even in such a case, A connected to the DC line 68
Since the C-DC converter 3b and the backup power supply 6b are sound, it is possible to continue supplying power to the load 13. Further, at the time of this failure, the backup power supply 3a detects a power failure and operates, but becomes an overcurrent state. At this time, the backup can be continued by promptly switching the switching means 70a to the DC line 68 side.

As described above, by dividing the DC line into two systems as in the configuration of this embodiment, the influence on the load can be minimized even when the DC line is short-circuited, and the system down can be avoided. it can.

[0099]

As described above, according to the present invention,
The parallel redundant operation of the backup power supply is possible and the system reliability is improved. In other words, when performing maintenance replacement of the secondary battery and other parts inside the backup power supply, hot-plugging / removing the backup power supply one by one allows the system to maintain the power outage compensation function and keep the load uninterrupted. Can be replaced without interruption.

Further, according to the present invention, since the connectors of the AC-DC converter and the backup power supply have the same specifications, the AC-DC converter and the backup power supply can be operated extremely even when the load increases as the system expands. It can be added easily and there is no need to stop the load at this time.

Further, in the present invention, the current sharing control is performed, so that the same current is output to the load from a plurality of backup power supplies during backup, so that the load of the backup power supplies becomes the same and the backup due to load concentration is performed. There is no need to worry about power deterioration. Further, in the unlikely event that one backup power supply fails, the load is not affected by first separating from the current share control and completely disconnecting from the system by the switch means provided on the output side of the backup power supply. .

Further, regarding the charging of the backup power supply, by setting the difference between the capacity and load of the AC-DC converter to the upper limit value of the charging current command value, the fastest rapid charging within the allowable range becomes possible. Should this happen, AC-D
When the C converter fails, the failure is detected and the charging current is reduced, so there is no risk of overload. In this way, it is possible to quickly prepare for the next power failure, thus improving the reliability of the system.

Further, by performing the peak cut control, it is possible to compensate for the peak current component from the backup power source for the peak load, and it is possible to reduce the rated capacity of the AC-DC converter. As a result, The cost and volume can be reduced.

Further, the bidirectional DC-DC converter of the backup power source described in the present invention has a very simple structure and can realize cost reduction, and also limits the current from the secondary battery even when the load is short-circuited. It is possible to prevent damage to the power supply or the load due to overcurrent in advance.

Further, the backup power supply insertion method of the present invention is a method in which after the output side capacitor is charged from the secondary battery, the switch means is gently turned on and connected to the system, and thus the influence on the load is extremely small. , Reliability is improved.

The present invention also proposes a bidirectional DC-DC converter using two secondary batteries, which improves reliability when the secondary battery fails and allows easy replacement of the secondary battery. Can be done. According to the present invention, even when the switch means is placed outside the device for schedule management, the operation of the backup power supply is switched in synchronization with the schedule, so that there is no fear of the system going down due to wasteful discharge or erroneous operation.

Also, by multiplexing the DC lines described in the present invention, it is possible to avoid a system down due to a short circuit failure of the DC lines and improve the system reliability.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a backup power supply with a hot-swap function according to a first embodiment of the present invention.

FIG. 2 is an AC-DC according to the first embodiment of the present invention.
It is a control circuit block diagram of a converter.

FIG. 3 is a block diagram of a control circuit for a backup power supply according to the first embodiment of the present invention.

FIG. 4 is a bidirectional DC according to the first embodiment of the present invention.
FIG. 6 is a circuit diagram of a DC converter.

FIG. 5 is an equivalent connection diagram of a charge upper limit value calculation circuit according to the first embodiment of the present invention.

FIG. 6 is a characteristic diagram showing a relationship between a load factor and a voltage of each part in the first embodiment of the present invention.

FIG. 7 is an equivalent connection diagram of a charge upper limit value calculation circuit according to a second embodiment of the present invention.

FIG. 8 is a characteristic diagram showing a relationship between a load factor and a voltage of each part in the second embodiment of the present invention.

FIG. 9 is a mounting layout diagram of a backup power supply with a hot-swap function according to a third embodiment of the present invention.

FIG. 10 is a mounting layout diagram of a backup power supply with a hot-swap function according to a fourth embodiment of the present invention.

FIG. 11 is a diagram showing a startup procedure of a backup power supply with a hot-swap function showing a fifth embodiment of the present invention.

FIG. 12 is a bidirectional D according to the sixth embodiment of the present invention.
It is a circuit diagram of a C-DC converter.

FIG. 13 is a bidirectional D according to the seventh embodiment of the present invention.
It is a circuit diagram of a C-DC converter.

FIG. 14 is a configuration diagram of a backup power supply with a hot-swap function according to an eighth embodiment of the present invention.

FIG. 15 is a configuration diagram of a backup power supply with a hot-swap function according to a ninth embodiment of the present invention.

FIG. 16 is a configuration diagram of a backup power supply with a hot-swap function according to a tenth embodiment of the present invention.

FIG. 17 is a diagram for explaining the operation of the backup power supply with the hot-swap function according to the eleventh embodiment of the present invention.

FIG. 18 is a configuration diagram of a backup power supply with a hot-swap function according to a twelfth embodiment of the present invention.

FIG. 19 is a configuration diagram showing a configuration of a conventional backup power supply with a built-in device.

FIG. 20 is a diagram showing an operation form of a conventional backup power supply with a built-in device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Commercial AC power supply, 2 ... Information processing apparatus, 3a, 3b, 3c ... AC-DC converter, 4a, 4b are secondary batteries, 5 ... Bidirectional DC-DC converter, 6a, 6b ... Backup power supply, 7 ... Blackout Detection circuit, 8a, 8b ... Smoothing capacitor, 9a, 9b ... Power MOSFET, 10a, 10b, 10c, 10d ... Connector, 11a, 11b, 11c, 11d, 11e ... Connector, 12 ... DC-DC converter, 13 ... Load 14a , 14b, 14c, 14d ... AC plug, 15a, 15b, 15c, 15d ... AC connector, 16 ... Power factor correction circuit, 17 ... Output control circuit, 18a, 18b ... Reverse current detection protection circuit, 19a, 19b ... Current detection means , 20, 21 ... DC line, 22 ... AC-DC converter current sharing signal line, 23 ... Backup power supply Flow share signal line, 24 ... AC-DC converter operating state signal line, 25 ... Operating state determination circuit, 26a, 26b ... Comparator, 27a, 27b ... Voltage error amplifier, 28a, 28b ... Voltage command value, 29a, 29b ... Addition , 30a, 30b ... Current error amplifier, 31a, 31b ... Diode, 32a, 32b ... Triangular wave generating means, 33 ... Voltage reference value, 34 ... Comparator, 35a, 35b ... Current detecting circuit, 36 ... Current detecting means, 37 ... Charge upper limit value calculation circuit, 38, 39 ... Operational amplifier, 40 ... Subtractor, 41, 42 ... Resistance, 43 ... Positive / negative inverting means, 44 ... Gain, 45 ... Integrator, 46 ... Control circuit, 47 ... Control circuit, 48 ... voltage detection means, 49 ... battery monitor, 50 ... discharge control circuit, 51 ... charging control circuit, 52 ... operation mode switching circuit, 3 ... driving circuit, 54a, 54b, 54c, 54d ... P-channel power M
OSFET, 55a, 55b, 55c, 55d ... Power MOSFE
T, 56 ... Inductor, 57a, 57b ... Smoothing capacitor, 58 ... Diode, 59a, 59b, 59c, 59d ... DC output line, 60 ... AC-DC converter, 61 ... Balance control part, 62 ... Charging circuit, 63 ... DC -DC converter, 64 ... Switch means, 65 ... Server, 66 ... Secondary battery, 67 ... Multi-output DC-DC converter, 68 ... DC line, 69a, 69b, 70a, 70b ... Switching means.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ identification code FI theme code (reference) H02M 3/155 H02M 3/155 W Y (72) Inventor Reiko Hatada 7-chome, Omika-cho, Hitachi City, Ibaraki Prefecture No. 1 Company Hitachi Ltd. Hitachi Research Laboratory (72) Inventor Satoru Masuyama 2880 Kozu, Odawara-shi, Kanagawa Hitachi Computer Equipment Co., Ltd. (72) Masato Isogai 1-88, Itora, Ibaraki-shi, Osaka Issue Hitachi Maxell, Ltd. F-term (reference) 5G015 FA18 GB02 HA16 JA07 JA08 JA32 JA52 KA03 5G065 AA00 BA02 DA01 DA06 EA06 FA01 GA06 HA01 HA07 JA04 LA01 MA01 MA10 NA03 NA06 PA04 PA05 5H730 AA13 AA16 AS01 AS08 AS21 AS22 BB13 BB14 BB14 BB14 BB14 BB86 CC01 CC11 CC16 CC17 DD04 DD12 DD13 EE13 FD01 FD31 XC19 XX50

Claims (21)

[Claims] 1. A backup power supply that backs up an AC-DC converter that converts AC received from a commercial AC power supply into DC, and a load connected to a DC output side of the AC-DC converter is operating. It is possible to insert the backup power supply into the device and connect it to the load, and disconnect the backup power supply from the load and remove it from the device while the load is operating. Backup power supply. 2. The backup power supply according to claim 1, wherein the backup power supply includes a bidirectional DC-DC converter, a secondary battery, a power failure detection means, and means for acquiring failure information of the AC-DC converter. Backup power supply. 3. The bi-directional DC-type according to claim 2.
The DC converter has a higher voltage on the DC line side connected to the load than the terminal voltage of the secondary battery, and has a step-down chopper circuit configuration from the load side, thereby charging the secondary battery, A backup power supply, wherein the step-down chopper circuit is used as a step-up chopper circuit to discharge the secondary battery to the load when a power failure is detected by the power failure detecting means or when the failure information is acquired. 4. The backup power supply according to claim 1, further comprising a current suppressing unit provided on the secondary battery side of the step-down chopper circuit. 5. The current suppressing means according to claim 4, wherein current limiting switch means is inserted between a positive electrode side of the secondary battery and an inductor forming the step-down chopper circuit, and a negative electrode of the secondary battery is provided. A backup power supply comprising a diode having an anode connected to a side thereof and a cathode connected to a connection point of the inductor and the current limiting switch means. 6. The bidirectional DC-in accordance with claim 2.
The DC converter has a lower voltage on the DC line side connected to the load than the terminal voltage of the secondary battery, has a step-up chopper circuit configuration as seen from the load side, and charges the secondary battery as well. , At the time of power failure or the AC
A backup power supply, characterized in that, when the DC converter fails, the boost chopper circuit is used as a step-down chopper circuit to discharge the secondary battery to the load. 7. The bidirectional DC according to claim 2, wherein the secondary battery is separated into two systems, and each secondary battery is connected to the bidirectional DC via battery switch means.
-A backup power supply, which is connected to a DC converter and in which the secondary battery is inserted and removed for each system. 8. The AC-DC converter according to claim 1, further comprising: the AC-DC converter and a DC-DC converter connected to a DC output side of the AC-DC converter. A converter that is integrated with the DC-DC converter is provided with a hot-swap function, an intermediate DC line of the converter is commonly connected to another converter, and at least one backup power supply is connected to the DC line. Backup power supply characterized by 9. The AC-DC converter according to claim 1, comprising the AC-DC converter and a DC-DC converter connected to a DC output side of the AC-DC converter. And a DC-DC converter integrated with a converter having a hot-swap function, an intermediate DC line of the two converters and the backup power supply are connected in different systems, and the backup power supply is connected to the DC line. A backup power supply characterized by having a switching means at a point to be operated. 10. The AC switch means for controlling ON / OFF of a commercial AC power source outside the apparatus according to claim 1, wherein the load controls ON / OFF of the AC switch means, A backup power supply for determining whether or not the backup power supply needs to be operated based on a signal sent from the load to the backup power supply. 11. The AC switch means for controlling on / off of a commercial AC power source and a server are provided outside the device according to claim 1, and the server controls on / off of the AC switch means. At the same time, the backup power supply determines whether or not the backup power supply needs to be operated by a signal sent from the server to the backup power supply via the load. 12. The peak power cutoff function according to claim 1, wherein the backup power supply supplies a current from the backup power supply to the load when the current of the load exceeds a predetermined value. Backup power supply characterized by having. 13. The backup power supply according to claim 1, wherein the backup power supply detects a backflow detector and a current that is equal to or more than a predetermined charging current, and the backup power supply is switched to another one. A backup power supply comprising an AC-DC converter and means for disconnecting the load. 14. The backup power supply according to claim 1, further comprising a plurality of backup power supplies, and means for balancing currents flowing from the backup power supplies to the load. 15. The backup power source according to claim 1, wherein the backup power source is provided with a circuit for calculating an upper limit value of a charging current, and the upper limit value of the charging current is:
A backup power supply characterized by monitoring the load current and the number of AC-DC converters currently in operation. 16. The AC-DC device according to claim 15.
A backup power supply, wherein a current share control line of a converter is connected to the backup power supply, and the load current is calculated from current information of the current share control line and a charging current of its own backup power supply. 17. The charge storage means of the output side inside the backup power supply according to claim 2, wherein when the backup power supply is inserted, the switch means connected to the load is inserted in a turned-off state. Is charged by the secondary battery in the backup power supply, and when the voltage of the switch means becomes substantially the same as the voltage of the load side, the switch means is turned on. 18. The backup power supply according to claim 1, wherein the AC-DC converter and the backup power supply have a common connector. 19. The backup power supply according to claim 1, wherein the AC-DC converter and the backup power supply have the same dimensions. 20. In any one of claims 1 to 19, two of the vertical, horizontal, and height dimensions of the backup power supply have the same dimensions of the AC-DC converter, and the other one is an integral multiple. Backup power supply characterized by: 21. A power supply circuit for converting an alternating current received from a commercial AC power supply into a direct current, and a backup power supply for backing up the power supply circuit, wherein the backup power supply is
A secondary battery and a DC-DC converter that converts the electric power of the secondary battery into a direct current and outputs it to a load, or converts the direct current power from the output of the power supply circuit into a direct current and outputs the direct current to the secondary battery, A power supply device comprising a control circuit for controlling the conversion output of the DC-DC converter.