JP2003324855A - Charging apparatus for electric double-layer capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To uniformly charge a plurality of electric double-layer capacitors connected in series or in parallel with each other, without balance resistors. <P>SOLUTION: Entire electric double-layer capacitors 10-1 to 10-n are charged by a DC power source 26. A common rectangular wave is input from a pulse power source 12 to DC reproducing circuits 14-1 to 14-n, in parallel with the charging of the capacitors, and DC-restored to charge the capacitors 10-1 to 10-n. Since the circuits 14-1 to 14-n operate to make the charging voltages of the capacitors 10-1 to 10-n converge to the rectangular double-amplitude voltage, double-amplitude voltage is set to the rate voltage, and thereby the charging voltages of all the capacitors 10-1 to 10-n can be converted to the rated voltage. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging device for an electric double layer capacitor used as a rechargeable power storage device, and more particularly to a device for charging a plurality of electric double layer capacitors connected in series or series / parallel.

[0002]

2. Description of the Related Art Electric double layer capacitors have been used as electric storage devices that are repeatedly used. The electric double layer capacitor is capable of rapid charging / discharging with a large current and has a feature of long life. On the other hand, since the rated voltage per unit is low, usually multiple capacitors are connected in series and used. Often. The electric double layer capacitor can be efficiently used by charging it to the full rated voltage, but it has a characteristic that it is rapidly deteriorated if it is charged more than the rated voltage. Therefore, when charging multiple electric double layer capacitors connected in series at the same time, we want to charge each capacitor evenly to the full rated voltage, but in reality, due to the variation in the capacity of each capacitor The time required for each capacitor is different. Therefore, it is necessary to perform charging while monitoring the charging voltage of each capacitor so as not to exceed the rated voltage.

As an example of a conventional apparatus for charging a plurality of electric double layer capacitors connected in series, a plurality of capacitors connected in series are simultaneously charged using one charging power source. In that case, the charging voltage of each capacitor is monitored, and the current flowing from the charging power supply to the capacitor is controlled so that the charging voltage of the capacitor does not exceed the rated voltage. Further, a balance resistor is provided in parallel with each capacitor, and a current is caused to flow through the balance resistor to suppress variations in charging voltage due to variations in capacitance of each capacitor.

[0004]

However, in the conventional device in which the balance resistance is provided in parallel with each capacitor, the electric power from the charging power source is stored as the electric energy of the capacitor, and the balance resistance is also stored. Will be consumed in. In particular, in an electric double layer capacitor, since a large current is handled, the power consumed by the balance resistor increases, so the charging efficiency deteriorates, and during discharging, the balance resistor must be disconnected to self-discharge. Therefore, there is a problem that charging is inconvenient.

The present invention has been made in view of the above problems, and when charging a plurality of electric double layer capacitors connected in series or series-parallel, it is possible to perform uniform voltage charging without a balance resistor. An object is to provide a charging device for a double layer capacitor.

[0006]

In order to achieve such an object, a charging device for an electric double layer capacitor according to a first aspect of the present invention comprises a plurality of electric double layer capacitors connected in series or in series and parallel. A device for charging, comprising: a pulse power source for outputting a pulse signal; and a plurality of direct current regeneration circuits provided for each electric double layer capacitor, each of the direct current regeneration circuits being common from the pulse power source. Of the electric pulse signal is input, and the pulse signal is DC-reproduced to flow a DC current to each electric double layer capacitor to charge each electric double layer capacitor.

As described above, each of the DC regenerating circuits DC regenerates a common pulse signal from the pulse power source and causes a DC current to flow to each of the electric double layer capacitors, thereby charging voltages of the plurality of electric double layer capacitors. Can be converged so as to be even, and variation in charging voltage due to variation in capacitance of the electric double layer capacitor can be suppressed. Therefore, when a plurality of electric double layer capacitors connected in series are charged, the electric double layer capacitors can be charged so that the respective voltages of the electric double layer capacitors are equalized without a balance resistor, and the charging efficiency can be improved.

A charging device for an electric double layer capacitor according to a second aspect of the present invention is the device according to the first aspect of the present invention, further comprising a DC power supply for charging the entire electric double layer capacitor. Characterize.

As described above, the pulse power supply can have a small capacity by further including the DC power supply for charging the entire electric double layer capacitor. further,
The time required to evenly charge the electric double layer capacitor to the rated voltage can be shortened.

A charging device for an electric double layer capacitor according to a third aspect of the present invention is the device according to the second aspect of the present invention, wherein the pulse power source has a switch element between the input and the output. A direct current signal from a direct current power source is input, the signal level is adjusted with respect to the direct current signal, and the switching operation of the switching element is performed, and the pulse signal is converted and output.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention (hereinafter referred to as embodiments) will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a charging device for an electric double layer capacitor according to an embodiment of the present invention. The charging device of this embodiment is roughly divided into a DC power supply 2
6, pulse power supply 12 and each electric double layer capacitor 10-
It is configured by a plurality of DC regeneration circuits 14-1 to 14-n provided for each of 1 to 10-n (n is a natural number). Although not shown, loads are connected to both ends of the electric double layer capacitors 10-1 to 10-n.

The output of the DC power supply 26 is connected to both ends of a plurality of electric double layer capacitors 10-1 to 10-n connected in series. As the DC power supply 26, for example, a DC-DC converter is used, and a DC voltage is input. Positive side terminal 5 of each of electric double layer capacitors 10-1 to 10-n
0-1 to 50-n includes a DC regeneration circuit 1 corresponding to it.
Output terminals 46-1 to 46-n of 4-1 to 14-n
Are connected respectively. DC regeneration circuit 14-1 to 1
The output terminal 38 of the pulse power supply 12 is commonly connected to the 4-n input terminals 42-1 to 42-n.
Voltage detection means 80-1 to 80-n for detecting the charging voltage of each of the electric double layer capacitors 10-1 to 10-n are provided at both ends of each of the electric double layer capacitors 10-1 to 10-n. The electric double layer capacitor 10-
The electric double layer capacitor 10-1 is provided at both ends of 1 to 10-n.
An overall voltage detecting means 16 for detecting the charging voltage of the entire 10 to 10-n is further provided. A current detecting resistor 20 is provided on the line between the DC power supply 26 and the electric double layer capacitor 10-1, and both terminals thereof are connected to the current control circuit 22.
Entered in. The current control circuit 22 detects the resistance for current detection when the voltage detection value of the overall voltage detection means 16 is smaller than a predetermined value and all the voltage detection values of the voltage detection means 80-1 to 80-n are smaller than the set value. From the DC power supply 26 to the electric double layer capacitor 10 based on the current detection value of 20.
The currents flowing from -1 to 10-n are controlled to have a constant value. On the other hand, when the voltage detection value of the overall voltage detection means 16 reaches a predetermined value, or the voltage detection means 80-1 to 80
If any of the -n voltage detection values reaches the set value,
The switch 70 in the DC power supply 26 is made non-conductive to stop the supply of power from the DC power supply 26 to the electric double layer capacitors 10-1 to 10-n. Here, the voltage detection means 80-1
When any of the voltage detection values of 80 to 80-n reaches the set value, the voltage is output to the OR circuit 90, and the switch 70
Becomes non-conducting. In addition, the predetermined value is set to, for example, a neighborhood value of (rated voltage × number of capacitors) or less, and the neighborhood value is set in consideration of variation in capacitance of the electric double layer capacitors 10-1 to 10-n. The set value is the maximum applied voltage determined by the characteristics of the electric double layer capacitors 10-1 to 10-n.

Next, an example of the configuration of the pulse power supply 12 in FIG. 1 will be described. The pulse power supply 12 includes an auxiliary DC power supply 36, switch elements 28 and 30, and a switch control circuit 24. The auxiliary DC power supply 36 is, for example, DC-
A DC converter is used, and the DC voltage from the DC power supply 26 is input. The switch element 28 is provided on the line between the output of the auxiliary DC power supply 36 and the output terminal 38 of the pulse power supply 12, and switches conduction / non-conduction between them.
The switch element 30 includes an output terminal 38 of the pulse power source 12,
It is provided on a line connecting both terminals of 40 and switches conduction / non-conduction between them. The switch element 28 and the switch element 30 are, for example, pMOSFET and nMO.
Each SFET is used, the control voltage from the switch control circuit 24 is input to its gate terminal, and when the switch element 28 is conductive, the switch element 30 is non-conductive,
When the switch element 28 is non-conductive, the switch element 30 is conductive. The output terminal 40 of the pulse power supply 12 is connected to the negative side terminal 52-n of the electric double layer capacitor 10-n.

Next, the DC regeneration circuit 14-m in FIG.
An example of the configuration (m is one of 1 to n) will be described. A capacitor 54-m is provided on the line between the input terminal 42-m and the output terminal 46-m. A diode 56-m is provided on the line between the capacitor 54-m and the output terminal 46-m, the anode side is connected to the capacitor 54-m, and the cathode side is the output terminal 46.
-M. The line between the capacitor 54-m and the diode 56-m, and the electric double layer capacitor 10-m
The diode 60 is connected to the line connecting the negative terminal 52-m of
-M is provided, the anode side is connected to the negative side terminal 52-m, and the cathode side is connected to the line between the capacitor 54-m and the diode 56-m.

Next, the charging operation in this embodiment will be described. DC power supply 26 to electric double layer capacitor 1
Current flows to 0-1 to 10-n and charging is performed. The current control circuit 22 controls the current flowing from the DC power supply 26 to the electric double layer capacitors 10-1 to 10-n.

On the other hand, in the pulse power source 12, the set output voltage of the auxiliary DC power source 36 is the electric double layer capacitor 10.
It is set to a rated voltage value of -1 to 10-n. Then, the switch control circuit 24 repeats turning on and off the input of the control voltage to the switch elements 28 and 30 so that the switch element 2
The conduction / non-conduction of 8 and 30 are alternately switched. Specifically, when a positive control voltage is supplied to the switch elements 28 and 30, the switch element 28 is non-conductive and the switch element 30 is conductive, and the control voltage is the switch elements 28 and 30.
When the voltage is not supplied to 30 and is close to 0 V, the switch element 28 is conductive and the switch element 30 is non-conductive. With the above operation, the pulse power supply 12 outputs a rectangular wave (pulse signal) whose both amplitudes are the rated voltage. The output of this rectangular wave is performed in parallel with the charging by the DC power supply 26,
The output rectangular wave is input to the DC reproduction circuits 14-1 to 14-n.

In the DC regenerating circuit 14-m, the rectangular wave from the pulse power source 12 is input to the input terminal 42-m. This rectangular wave passes through the capacitor 54-m and is subjected to DC regeneration by the diode 60-m. At this time,
The diode 56 is arranged so that the potential of the positive side terminal 50-m of the electric double layer capacitor 10-m becomes higher than the cathode potential of the diode 60-m by the amplitude voltage of both rectangular waves.
Charging is performed by passing a current through the -m to the electric double layer capacitor 10-m. The anode side of the diode 60-m is the negative side terminal 52 of the electric double layer capacitor 10-m.
-M, the electric double layer capacitor 10
The charging voltage of -m acts so as to converge to both amplitude voltages of the rectangular wave, that is, the rated voltage. This action works in parallel for all electric double layer capacitors 10-1 to 10-n.

As described above, the electric double layer capacitors 10-1 to 10-n are charged by the DC power supply 26 and the DC regenerating circuits 14-1 to 14-n, and the detection value of the total voltage detecting means 16 is ( When a neighborhood value less than or equal to (rated voltage × number of capacitors) is reached, or the voltage detection means 80-1 to 80-8
When any of the voltage detection values of 0-n reaches the set value, the switch 70 in the DC power supply 26 is made non-conductive to stop the charging by the DC power supply 26 and the DC regeneration circuits 14-1 to 14-1.
Switch to charging by 14-n only. Then, constant voltage charging is performed until the charging voltage of all electric double layer capacitors 10-1 to 10-n reaches the rated voltage.

In this embodiment, a common rectangular wave from the pulse power source 12 is input to the DC regenerating circuits 14-1 to 14-n, and this rectangular wave is regenerated to the DC regenerating circuits 14-1 to 14-n.
DC regeneration by electric double layer capacitors 10-1 to
10-n are charged respectively. Here, since the electric double layer capacitors 10-1 to 10-n have variations in capacitance, if charging is performed only by the DC power supply 26, variations in charging voltage will occur. However, in the present embodiment, the DC regeneration circuit 14-m acts so as to converge the charging voltage of the electric double layer capacitor 10-m to both amplitude voltages of the rectangular wave, and this rectangular wave is the DC regeneration circuits 14-1 to 14-14. Since it is commonly input to -n, it acts to converge the charging voltage of all electric double layer capacitors 10-1 to 10-n to both amplitude voltages of a uniform rectangular wave. Then, the charging voltage of all the electric double layer capacitors 10-1 to 10-n can be converged to the rated voltage by setting both amplitude voltages of the rectangular wave to the rated voltage. Therefore, it is possible to uniformly charge the electric double layer capacitors 10-1 to 10-n by suppressing variations in the charging voltage due to variations in the capacities of the electric double layer capacitors 10-1 to 10-n without using a balancing resistor. Further, by increasing the value of the current flowing from the DC power supply 26 to the electric double layer capacitors 10-1 to 10-n, it is possible to use the auxiliary DC power supply 36 having a small capacity and to charge the auxiliary voltage evenly to the rated voltage. The time required for can be shortened.

FIG. 2 shows a simulation result of the charging operation by the charging device of this embodiment. However, in this simulation, the number of electric double layer capacitors connected in series is 6, and the rated voltage of the electric double layer capacitors is 2.3V. FIG. 2 shows the negative terminal 52-
The time change of the potential of the positive-side terminal 50-m of the electric double layer capacitor 10-m based on the potential of n (n = 6 in this simulation) is shown. As shown in FIG. 2, the potential difference between the positive side terminals of the adjacent electric double layer capacitors is 2.3.
It converges on V. That is, the charging voltage of all electric double layer capacitors has converged to the rated voltage. As described above, in the charging device of the present embodiment, all electric double layer capacitors can be uniformly charged to the rated voltage.

The present embodiment is not limited to the above description, and various modifications can be made within the scope of reflecting the technical idea of the present invention. For example,
DC power supply 26 and DC regeneration circuit 14-1 from the start of charging
14-n may not be used for charging, and only the DC power supply 26 may be initially charged and charging by the DC regeneration circuits 14-1 to 14-n may be started during charging. Both amplitude voltage values of the rectangular wave do not have to be constant rated voltage values, and the amplitude may be changed according to the detection value of the overall voltage detection means 16 and finally set to the rated voltage for charging. . Further, the configurations of the DC power supply 26 and the auxiliary DC power supply 36 are not limited to the DC-DC converter, and may be anything as long as the DC voltage can be output. The charging method by the DC power supply 26 is not limited to the constant current charging. Further, the DC regenerating circuit 14-1 is provided without the DC power source 26.
Charging may be performed using only ~ 14-n. Further, the present invention is applicable not only when charging the electric double layer capacitors connected in series but also when charging the electric double layer capacitors connected in series and parallel.

[0023]

As described above, in the present invention, each of the direct current regeneration circuits receives the common pulse signal from the pulse power source, regenerates the direct current of the pulse signal and outputs the direct current to the electric double layer capacitor. By flowing to each, when charging multiple electric double layer capacitors connected in series or series / parallel, without charging the balance resistance, variation in the charging voltage due to variation in the capacitance of the electric double layer capacitors is suppressed, and charging is performed evenly. can do. Therefore, the charging efficiency can be improved, and the electric double layer capacitor can be accurately charged without deterioration.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a charging device for an electric double layer capacitor according to an embodiment of the present invention.

FIG. 2 is a diagram showing a simulation result of a charging operation in the embodiment of the present invention.

[Explanation of symbols]

10-1 to 10-n Electric Double Layer Capacitor, 12 Pulse Power Supply, 14-1 to 14-n DC Regeneration Circuit, 16
Overall voltage detection means, 20 current detection resistors, 22 current control circuit, 26 DC power supply, 80-1 to 80-n voltage detection means.

Continued front page    (72) Inventor Narumi Hayakawa             2-10-19 Tairiri, Ueda, Nagano Prefecture Ueda Sun             Inside the radio company (72) Inventor Setsumoto Setsuo             2-10-19 Tairiri, Ueda, Nagano Prefecture Ueda Sun             Inside the radio company F-term (reference) 5G003 AA01 BA03 CA12 CA14 CC08

Claims (3)

[Claims] 1. A device for charging a plurality of electric double layer capacitors connected in series or series-parallel, comprising: a pulse power source for outputting a pulse signal; and a plurality of DC regenerators provided for each electric double layer capacitor. A common pulse signal from the pulse power source is input to each of the DC regenerator circuits, and the DC signal is regenerated by causing a DC current to flow to each of the electric double layer capacitors. An electric double layer capacitor charging device, characterized in that each of the multilayer capacitors is charged. 2. The charging device for an electric double layer capacitor according to claim 1, further comprising a DC power supply for charging the entire electric double layer capacitor. . 3. The electric double layer capacitor charging device according to claim 2, wherein the pulsed power supply has a switch element between input and output, and a DC signal from the DC power supply is input to the pulsed power supply. A charging device for an electric double layer capacitor, characterized in that a signal level is adjusted for the DC signal and a switching operation of the switch element is performed to convert into a pulse signal for output.