JPH10112942A - Dc power supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the reliabilities of storage batteries, to enhance the preventive maintenance for the batteries, and to eventually provide a DC power supply device which is as a whole small in size and has a high efficiency, by measuring the capacity of one storage battery being in parallel operation. SOLUTION: In this DC power supply device, a plurality of units 11, 12, 13..., with one unit being a circuit constituted of an AC rectifying circuit section 115, a storage battery 113, and a DC-DC converting section 116, are parallelly connected to supply power to a load 20. Each unit is provided with an operation stopping means 117, a voltage measuring means 118, and an output voltage variable command means 119, and therefore a command signal can be transmitted between the AC rectifying circuit section 115 and the DC-DC converting section 116.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a DC power supply capable of measuring the capacity of one storage battery in parallel operation.

[0002]

2. Description of the Related Art Conventionally, as a DC power supply for a stationary communication device, conventionally, it is necessary to combine a storage battery and a DC-DC converter into a unit and connect a plurality of the unitized power circuits in parallel. It can be used from the viewpoint of miniaturization and high reliability. The idea of unitization is, for example, Japanese Unexamined Utility Model Publication No. Hei 4-39039, Japanese Unexamined Patent Publication No. Hei 5-276689, and Japanese Unexamined Patent Publication No. Hei 6-189469.

[0003] The DC power supply device shown in FIG.
This shows a configuration in the case where Japanese Patent Application Laid-Open No. 5-276689 is applied to a DC power supply. 7, reference numeral 10 denotes an AC power source, 11, 12, 13,..., DC power supply units connected in parallel, and 20, a load. DC power supply unit 11
And the like have the same internal configuration, and they are rectifying and smoothing circuits 11 for rectifying and smoothing input AC and outputting DC.
1, a DC-DC converter 112 for stabilizing the DC to a constant voltage, a storage battery 113 floatingly charged by the output of the converter, and a DC power input from the DC-DC converter 112 and the storage battery 113 as a load. 20 is a load voltage stabilizing circuit 114 for stabilizing the supply voltage when supplying to the power supply 20.

The DC-DC converter 112 uses a well-known switching power supply to satisfy the requirements of miniaturization and high performance, and to maintain insulation between input and output. As an operation when the AC power supply is normal, the DC input from the rectifying / smoothing circuit 111 is stabilized to a constant voltage, and the voltage is applied to the DC voltage stabilizing circuit 114 while the storage battery 113 is floatingly charged.

[0005] The storage battery 113 supplies power to the load 20 when the AC power supply fails. Therefore, when the terminal voltage is
The required number of storage batteries are connected in series so as to be substantially equal to the rated voltage of the storage battery. For example, for a load with a rated voltage of 48 V, two storage battery cells are connected in series.

[0006] The load voltage stabilizing circuit 114 includes a storage battery 113.
Is different between charging and discharging, and the difference voltage exceeds the allowable terminal voltage range of the load. If the voltage is higher than the load terminal rated voltage during floating charging, a silicon dropper is used for stepping down. If the floating charge voltage is lower than the load voltage, a booster converter is used for boosting.

Each of the DC power supply units 11, 12, 13,... Has a relatively small capacity, and is connected in parallel with each other to supply power to the load 20 while sharing power.
By providing such redundancy, it is possible to prevent the entire system from going down due to a failure of the DC power supply unit, and to increase the reliability of the device.

[0008]

In the above-mentioned power supply device, the characteristics of the power supply device except for the storage battery 113 hardly change even after the use time elapses. However, the storage battery 113 is a so-called consumable and has a charging capacity during use. It is necessary to know exactly. Recently, the maintenance performance has been improved due to the sealed type of lead storage battery, but as described above, even one of the storage batteries connected in series of 20 or more has poor characteristics compared to the others. In such a case, good operation as a storage battery cannot be maintained. In such a case, when the power supply of the AC power is cut off and the power supply is switched to the power supply from the storage battery, the voltage at both ends of the storage battery drops abnormally quickly with the lapse of time, and the operation cannot be covered by another unit. It is.

In general, the most reliable means of determining the charge capacity of a storage battery is to check the time to the end of discharge while actually discharging the storage battery to check the capacity. In the DC power supply device shown in FIG. 7, it is appropriate to make only the DC power supply unit 11 into an AC input power failure state, supply power to the load by the storage battery 113, and check the capacity of the storage battery 113. Is completely defective, and depending on the power supply from the other DC power supply units 12, 13,. Therefore, the characteristics other than the DC power supply unit to be in the power failure state are complete, and even when testing one power supply unit as described above, it is necessary to prepare beforehand such as confirming that the operation cover can be sufficiently provided.

[0010] Other than the above-mentioned capacity confirmation, complicated means have been adopted. It is a troublesome means to remove the storage battery to be measured from the unit without disconnecting the specified power supply unit from the power failure state, connect a temporary storage battery instead, and connect a discharge resistor outside the removed battery to perform a discharge test. there were. In the past, when the device was in operation, it was difficult to determine the capacity of the storage battery by a discharge test, so-called preventive maintenance could not be performed, and when the storage battery had passed the standard service life, it did not matter whether it was good or bad. Had been replaced. As a result, there is a disadvantage that the maintenance and maintenance cost of the apparatus is high.

As the rectifying / smoothing circuit 111 shown in FIG. 7, a capacitor-input-type smoothing circuit having a simple structure has been conventionally used. The capacitor input type smoothing circuit includes a circuit 111
Output current contains many harmonics and has the drawback that the waveform is distorted.
Is often used. If a high power factor converter is used, it is necessary to use three converters in one DC power supply unit, including the converter of the DC-DC converter 113 of the next stage and the booster converter of the load voltage stabilizing circuit 114. Becomes In that case, there is a drawback that the device becomes large and the power use efficiency naturally decreases.

An object of the present invention is to improve the reliability of the storage battery and improve the preventive maintenance by measuring the capacity of the storage battery even during the operation of the apparatus to improve the above-mentioned drawbacks. It is to provide a DC power supply.

[0013]

In order to achieve the above-mentioned object, an AC rectifying circuit section having a rectifying / smoothing circuit for input AC and a constant voltage charging circuit, and a storage battery charged by the output of the AC rectifying circuit section are provided. A DC power supply circuit composed of the AC rectifier circuit output and a DC-DC converter to which a storage battery output is input as one unit, and a plurality of units connected in parallel to supply a load to a load. In the apparatus, the present invention employs the following configuration. That is, claim 1
According to the invention, each unit has an operation stop command unit for an AC rectification circuit unit of each unit, a voltage measurement unit for a storage battery of each unit, and a command unit for varying an output voltage to a DC-DC conversion unit of each unit. With
Further, the AC rectification circuit section of each unit is provided with a signal input terminal for receiving a command signal from the operation command means, and a corresponding circuit for stopping the operation, and the storage battery of each unit is provided with the voltage measurement means. The DC-DC converter of each unit is provided with a signal input terminal for receiving a command signal from the output voltage varying command means, and a circuit for varying the output voltage correspondingly. It is characterized by the following.

According to a second aspect of the present invention, there is provided an integrated commanding means for instructing the operation stopping means, the voltage measuring means, and the output voltage variable commanding means to perform simultaneous operations on the means, and the storage battery voltage. And a storage battery capacity calculating means for processing a measured voltage of the measuring means to obtain a charged capacity of the storage battery.

According to a third aspect of the present invention, when the capacity of the storage battery based on the value measured by the storage battery voltage measuring means is equal to or less than a specified value, the deterioration of the storage battery in the unit is reduced. It is characterized by comprising an alarm means for judging and outputting an alarm prompting replacement.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram showing an embodiment of the invention according to claim 1, wherein an AC rectifier circuit section 115 for an input AC 10 and a storage battery charged by the output of the AC rectifier circuit section 115. 113, a DC-DC converter 116 to which the output of the AC rectifier circuit 115 and the output of the storage battery 113 are input.
Are configured as a single unit, and a plurality of units 11, 12, 13,... Are connected in parallel to each other and supplied to a load 20.

Each of the units 11, 12, 13, and 13 shown in FIG.
Are provided with operation stop command means 117 for the AC rectification circuit unit of each unit, voltage measurement means 118 for the storage battery of each unit, and command means 119 for varying the output voltage for the DC-DC converter of each unit. ing. The AC rectification circuit unit 115 of each unit has a signal input terminal for receiving a command signal from the operation stop command unit 117,
A circuit for correspondingly stopping the operation is provided, and the DC-DC converter 116 of each unit is provided with a command means 1 for varying the output voltage.
A signal input terminal for receiving a command signal from the control unit 19 and a circuit for correspondingly varying an output voltage are provided.

The DC power supply shown in FIG.
Are normal and the units 11, 12, 13,... Are also normal, the storage battery of each unit, for example, the storage battery 113 of the first unit, is so-called floating charged and is in a substantially charged state. The DC-DC converter 11 of each unit
The output voltage of the load 4 is adjusted to be a specified voltage for the load 20, and the current for the load 20 is shared equally by each unit.

If the input AC 10 loses power,
The storage battery of each unit enters a discharge state, and supplies the same voltage and current to the load 20 via the DC-DC converter of each unit as in the normal state. Therefore, normally, if the storage battery characteristics are normal, the operation of the load is normal until the storage battery is discharged.

If the discharge test can be performed on the storage battery of each unit when the input AC 10 is normal, the maintainability of the DC power supply is greatly improved. Therefore, each unit shown in FIG. 1 is provided with an operation command means for the purpose. For example, a case where a test is performed on each unit shown in FIG. 1 will be described below. The operation stop unit 117 for the AC rectification circuit unit 115 first issues an operation stop command for the AC rectification circuit unit 115 to generate a power outage state for the first unit. The terminal voltage of the storage battery 113 is measured by the voltage measuring means 118. If the terminal voltage is in a completely abnormal state, the discharge test is immediately stopped, the connection of the storage battery is disconnected, and the normal storage battery is replaced and connected. Next, the operation of the AC rectifier circuit is restored. When the terminal voltage of the storage battery is not abnormal, the following operation is performed.

At this time, the output voltage variable command means 119 issues a command to the DC-DC converter 116 to slightly increase the output voltage. The command is sent to the DC-DC converter 11
6 and reaches the terminal with the output voltage variable command means 119. The DC-DC converter 116 converts the DC power input from the storage battery 113 into a specified voltage, and at the same time, boosts the power slightly more than before to supply the load 20. At this time, the unit bears a larger amount of load current than the other units, so that the output current value increases and finally reaches the droop point of the unit. Due to the current value, the output voltage of the unit drops to the same voltage as the other units. This “drop point” will be described later.

Therefore, at this time, since the output current value of the unit is the maximum and the output voltage is the same value, the unit is in the maximum output state, and the state is not related to the magnitude of the load. From the storage battery 113, the DC-DC converter 116
To the DC-DC converter 116
Generates the maximum output, the input power thereof, that is, the discharge power of the storage battery 113 is substantially constant, and the discharge test is performed under constant conditions. If the terminal voltage of the storage battery 113 is monitored by the voltage measuring means 118 and the time until the voltage drops to the predetermined discharge voltage is measured, the capacity of the storage battery can be accurately obtained based on the length of the time.

FIG. 2 is a diagram showing a specific configuration of the DC-DC converter 116 shown in FIG. In FIG. 2, 21 is a current input terminal from a storage battery, and 22 is a FET.
Switch 23, a transformer 23, a rectifier diode 24, a smoothing circuit 25, a current detector 26, a flow angle controller (including a circuit for varying the output voltage) for the FET 27, and an output 28 A current detector, 29 is a current output terminal from the DC-DC converter to the load 20, and 40 is a fuse.

The output capacitance from terminal 21 to terminal 29 is
Since the characteristics of the DC-DC converter 116 are predetermined, the output current detector 28 detects the output of the current detector 26, and the output voltage variable command means 119 shown in FIG.
Is received via the signal input terminal provided in the DC-DC converter 116, the control amount of the flow angle with respect to the FET for setting the maximum output state can be determined. By applying that amount of control to FET 22, the current at terminal 29 will be at a maximum value. Since the terminal 29 is connected in parallel with another unit, the output voltage of the terminal 29 is stabilized in common.

FIG. 3 is a diagram showing changes in output voltages and output currents of the units 11 and 12 shown in FIG. FIG. 3A shows the first unit 11, and FIG.
The output of each unit 12 is shown, and the time tt on the horizontal axis in each figure is shown.
In, a discharge test of the storage battery is started. At time tt, the output voltage of the first unit slightly increases (for example, 5%) as described above, and the output current increases greatly, and continues thereafter. The output current of the second unit or lower decreases in accordance with the number of parallel units of the second unit or lower. For example, when up to the third unit is connected in parallel, the output currents of the second and third units decrease by half the value of the increased current of the first unit. Thereafter, the output voltage of the first unit gradually decreases, and after reaching the same voltage as the other units, stabilizes at that voltage.

FIG. 4 is a diagram for explaining the drooping characteristic of the DC-DC converter 116. The power supply has a specific rated capacity like the DC-DC converter 116, and if a load that requires driving exceeding the capacity is connected, the power supply is destroyed. Therefore, the output current is constantly monitored, and the output current is constantly monitored. %, The output voltage is kept constant (constant voltage control).
The constant voltage is denoted by Vo. If the output current is 110% or more of the rating, the control is switched to the constant current control so that the large current does not flow. The transition to the constant current control is called a drooping operation, and the point at which the constant voltage region switches to the constant current region is called a drooping point. Operating in the constant current region beyond the droop point is called drooping operation. In the case of the present invention, the output voltage of the device in the constant current region is the output voltage of the device (unit) that is not drooping because the units are connected in parallel. Since the output current value Io in the drooping operation is maximum and the output voltage is large, this unit is operating at the maximum output.

The operation stop command means 117 shown in FIG. 1 issues a command to stop driving the IGBT which is an operation element in the AC rectifier circuit unit 115. AC rectifier circuit 115
Is provided with a signal input terminal for receiving the command, and the operation of the element stops when the command signal is received.

As the voltage measuring means 118, a well-known means is employed. The terminal voltage of the storage battery is constantly measured and monitored.
FIG. 5 is a diagram showing the voltage of the storage battery after the start of the discharge test as time elapses. The terminal voltage of the storage battery is Vt
However, it falls to the right as time passes. By determining the discharge end voltage Vb for each type of storage battery, for example, 1.9 V / cell, the time required to decrease to Vb is measured. A standard time to reach Vb is defined as tr. When the time during which a predetermined storage battery has dropped to Vb is measured and the time is long as at t1, it indicates that the storage battery indicating the progress line Ba has a sufficient discharge capacity. The storage battery whose voltage reaches Vb in a short time such as the discharge time t2 is a lapsed line Bd, and has insufficient capacity. It is desirable that the voltage measuring means 118 notifies that the replacement is required immediately by issuing an alarm or the like.

FIG. 6 shows a first embodiment of the invention according to claim 2.
Here is an example. FIG. 6 is a block diagram of the centralized monitoring unit 30 capable of issuing commands to the units shown in FIG. 1 in an integrated manner and displaying test results. The centralized monitoring unit 30 designates a storage battery of a specific unit, issues a command to execute a discharge test for the storage battery, and a command unit 31 for performing a test as described above and obtaining test data based on the data. Test data calculation unit 33 for determining pass / fail
1, a display unit 32 for displaying an output of a storage battery discharge test result to which an output 36 of the arithmetic unit 33 is input, a communication line 34 for transmitting a command to each unit shown in FIG. A communication line 35 for receiving test data is provided. The storage battery under test needs to be set cyclically at predetermined intervals.

In one embodiment of the present invention, when it is determined that the capacity of the storage battery is equal to or less than the specified value, an alarm prompting replacement of the storage battery is output.
The drive of T is stopped, the power supply from the unit to the load is stopped, and the storage battery is replaced. If this operation is not performed, the DC-DC converter will not operate as a whole due to power supply from the storage battery that has been reduced to a low capacity.

[0031]

According to the first aspect of the present invention, a discharge test can be performed on the storage batteries inside the power supply unit connected in parallel even while the load 20 is in operation, so that preventive maintenance on the storage batteries can be performed. This has the effect of improving the properties. At this time, the storage battery to be tested is not removed from the system or a temporary storage battery is not required, and new equipment for the test is almost unnecessary, and the test can be executed periodically. And since the discharge current can be kept constant at the maximum value, it is similarly applied to other units,
The accuracy of the test can be significantly improved. Conventionally, three converters were cascade-connected. However, according to the present invention, even if a converter is used in the AC rectification circuit unit, up to two converters may be used.
The equipment space of the device may be small.

According to the second aspect of the present invention, it is possible to instruct to periodically execute the discharge test and to display the result, so that the utilization of the equipment can be effectively used. Claim 3
According to the invention, when a defective storage battery is found as a result of the discharge test, the defective storage battery can be promptly replaced, so that the power can be stably supplied to the load at the time of an actual power failure.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the invention according to claim 1;

FIG. 2 is a diagram showing a specific configuration of a DC-DC converter shown in FIG.

FIG. 3 is a diagram showing changes in voltage and current for units 11 and 12 shown in FIG.

FIG. 4 is a diagram illustrating drooping characteristics of a DC-DC converter.

FIG. 5 is a diagram showing the voltage of the storage battery after the start of the discharge test with the passage of time.

FIG. 6 is a diagram showing an embodiment of the invention according to claim 2;

FIG. 7 is a diagram showing a configuration of a conventional DC power supply device.

[Explanation of symbols]

10 Input AC 11, 12, 1
3, ... Unit 20 Load 21 Current input terminal from storage battery 22 DC switch by FET 27 Flow angle control unit 28 Output current detector 30 Centralized monitoring unit 113 Storage battery 115 AC rectification circuit unit 116 DC-DC conversion unit 117 Operation stop command Means 118 Voltage measuring means 119 Output voltage variable command means

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI H02M 3/00 H02M 3/00 W (72) Inventor Masahiro Utashiro 597 Jingzawa Uehara, Imaichi-shi, Tochigi Furukawa Battery Co., Ltd. Inside the city office (72) Inventor Katsuhiro Horiuchi 597 Jingzawa Uehara, Imaichi-shi, Tochigi Prefecture Furukawa Battery Co., Ltd. (72) Inventor Eiji Moriyama 4-8-33 Shibaura, Minato-ku, Tokyo Kandenko Co., Ltd.

Claims (3)

[Claims] An AC rectifier circuit having a rectifying / smoothing circuit for input AC and a constant voltage charging circuit, a storage battery charged by the output of the AC rectifier circuit, and an output of the AC rectifier circuit and an output of the storage battery. A DC power supply circuit constituted by a DC-DC converter to be provided as one unit, and a plurality of units connected in parallel to supply a load to a DC power supply device. Operation stop command means for the AC rectification circuit unit, voltage measurement means for the storage battery of each unit, and DC-
Command means for varying the output voltage to the DC converter, and the AC rectifier circuit of each unit is adapted to stop operation in response to a signal input terminal for receiving a command signal from the operation command means. The circuit of each unit, the storage battery of each unit is provided with a connection terminal for the voltage measuring means, the DC-DC converter of each unit is a signal input terminal for receiving a command signal from the output voltage variable command means, And a circuit for varying an output voltage correspondingly. 2. An integrated commanding means for instructing the operation stop means, the voltage measuring means, and the output voltage variable commanding means according to claim 1 to perform a simultaneous operation to the means, and a measuring voltage of the storage battery voltage measuring means. 2. The direct-current power supply according to claim 1, further comprising a storage battery capacity calculating means for performing processing to obtain a charging capacity of the storage battery, and a communication line for communicating with each of the means. 3. When the capacity of the storage battery based on the value measured by the storage battery voltage measuring means according to claim 1 or 2 is equal to or less than a specified value, it is determined that the storage battery in the unit is deteriorated, and replacement is urged. A DC power supply device comprising an alarm unit for outputting an alarm.