JPH10261551A - Apparatus for aging electrolytic capacitors - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a apparatus for aging electrolytic capacitors in a short time, without needing the step of selecting the broken electrolytic capacitor after aging. SOLUTION: Electric bulbs L11 , L21 -Ln2 are connected in series to electrolytic capacitors C1 -Cn and a voltage is applied to the capacitors through the bulbs to quickly raise the capacitor terminal voltages to a power source applied voltage, thereby aging the capacitors in a short time. The lighting condition of the bulbs is monitored to detect the breakdown of the capacitors during aging.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aging device for an electrolytic capacitor, and more particularly, to an electrolytic capacitor connected in series with a light bulb having a positive temperature coefficient of resistance, and using a large resistance change of the light bulb to appropriately supply a current. The present invention relates to a technology for performing aging in a short time while suppressing heat generation of an electrolytic capacitor by restricting.

[0002]

2. Description of the Related Art Generally, an electrolytic capacitor is formed by interposing an electrolyte between an anode electrode and a cathode electrode each having an oxide film such as a metal oxide formed on a surface thereof. For example, in a foil type electrolytic capacitor, the surface of a metal foil such as aluminum constituting the anode electrode is oxidized to a metal oxide film of aluminum oxide, which is opposed to the cathode electrode of the metal foil such as aluminum via an electrolyte solution. Let me.

In the manufacturing process of such an electrolytic capacitor, a part of the metal oxide film may be damaged.
This breakage of the metal oxide film degrades the performance of the electrolytic capacitor or renders it unusable. Therefore, after assembling the electrolytic capacitor, aging is performed to re-form the metal oxide film of the electrolytic capacitor to repair the metal oxide film. This aging is performed by applying a re-forming voltage determined by characteristics such as the capacity and withstand voltage of the electrolytic capacitor to both electrodes of the electrolytic capacitor for an appropriate time.

When an electrolytic capacitor is to be aged, the flowing current is limited within a certain frame to prevent a rise in the temperature inside the electrolytic capacitor element during aging, so that the electrolytic capacitor can be re-formed in a short time without deterioration. It can be carried out. Therefore, as a current limiter,
A resistor, a constant current diode, a PTC thermistor, and the like are connected in series with the electrolytic capacitor to perform aging of the electrolytic capacitor.

[0005]

However, when a resistor is used as the current limiter, it is necessary to set the resistance value in consideration of the internal resistance of the electrolytic capacitor element. In particular, when a plurality of electrolytic capacitors are connected in parallel. It is difficult to set the resistance value appropriately, for example, when performing aging treatment. In addition, there is also a disadvantage that it takes a relatively long time to increase the terminal voltage of the electrolytic capacitor, and the aging processing time becomes longer.

When a semiconductor element such as a PTC thermistor or a constant current diode having a positive temperature coefficient of resistance is used as a current limiter, the self-heating of the PTC thermistor element or the constant current when a certain current or more flows. Due to the current-voltage characteristics of the diode, the resistance value of the semiconductor element increases, which acts to suppress an excessive increase in current. Also, even if the internal resistance between the electrolytic capacitors varies somewhat, a current close to a constant current can be stably flowed. However, in a semiconductor device, for example, a PTC thermistor reflects the current-voltage characteristics of a constant current diode due to a forward voltage, and the final voltage of an electrolytic capacitor becomes lower than the applied voltage of a power supply, resulting in poor efficiency. Was.

Furthermore, the variable range of the resistance of the PTC thermistor often does not have an appropriate resistance value for aging. When the PTC thermistor is used for aging of an electrolytic capacitor, it is actually used in combination with another resistance element. There is a need to. Therefore, the resistance change range cannot be sufficiently increased as an aging resistance element,
It was not possible to further reduce the aging time.

Further, when the electrolytic capacitor element is broken during aging, for example, breakage of a wire or short-circuit is required, it is necessary to remove the broken element. However, in some cases, the broken element was indistinguishable in appearance, and a screening test had to be performed again after aging. For this reason, there have been inconveniences such as a complicated manufacturing process of the electrolytic capacitor and an increase in manufacturing cost. Furthermore, small breaks can be temporarily repaired and cause failure later, but such small breaks have been difficult to sort after aging.

SUMMARY OF THE INVENTION An object of the present invention is to provide an aging apparatus for an electrolytic capacitor which can accurately perform an aging process for the electrolytic capacitor in a short time in view of the above-mentioned problems in the prior art.

Another object of the present invention is to provide an aging apparatus for an electrolytic capacitor in which a terminal voltage of the electrolytic capacitor can quickly reach a voltage applied to a power supply.

It is still another object of the present invention to provide an electrolytic capacitor aging apparatus which does not need to sort out a broken electrolytic capacitor by a sorting tester after the aging treatment is completed.

[0012]

According to the present invention, there is provided an aging device for an electrolytic capacitor, the aging device for an electrolytic capacitor comprising: a bulb connected in series to an electrolytic capacitor to be aged; A DC power supply for applying an aging voltage to the electrolytic capacitor. With such a configuration, ideal aging conditions can be accurately realized.

In this case, the light bulb may be an incandescent light bulb. With such a configuration, the aging processing time of the electrolytic capacitor is shortened, and ideal aging conditions can be easily and accurately realized.

The aging device for an electrolytic capacitor further includes circuit switching means for disconnecting a circuit composed of the electrolytic capacitor and the bulb connected in series from the DC power supply and short-circuiting both ends of the circuit. After applying an aging voltage to the electrolytic capacitor via the electric bulb by the power supply, the circuit switching means short-circuits the circuit composed of the electrolytic capacitor and the electric bulb connected in series to discharge the electrolytic capacitor. Can also. Thus, a series of processes from aging to discharging of the electrolytic capacitor can be performed consistently using one device.

[0015] The aging device for the electrolytic capacitor may include means for detecting the light intensity of the light bulb, and the aging state may be monitored based on the light intensity of the light bulb. With such a configuration, it is possible to monitor the light of the light bulb and detect the destruction of the electrolytic capacitor during aging.

Further, in this case, the aging device for the electrolytic capacitor may be configured such that the aging device applies the aging voltage to the electrolytic capacitor via the bulb based on an output signal of a means for detecting the light intensity of the bulb. It can also be configured to detect destruction of the capacitor. With such a configuration, it is possible to easily and reliably detect the destruction of the electrolytic capacitor during aging.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An aging apparatus for an electrolytic capacitor according to the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic circuit of an electrolytic capacitor aging apparatus according to an embodiment of the present invention.

In FIG. 1, for example, there are _n electrolytic capacitors to be aged, for example, C _{1 to} C _n , each of which has a positive temperature coefficient of resistance, whose electric resistance increases with increasing temperature. number of bulbs (for example, two light bulbs _{L 11} and _{L 12} for the electrolytic capacitor _{C 1)} are connected in series. As the light bulb, a light bulb having a filament, for example, an incandescent light bulb is used.
Each of the electrolytic capacitor _C 1 -C _n, for example, _{C 1} is
Although shown as a single electrolytic capacitor, it may be configured as a set in which a plurality of electrolytic capacitors are connected in parallel as necessary in consideration of the type and number of electrolytic capacitors to be aged. The capacitance of each of C _{1 to} C _n is set to 10 so that the magnitude of the current flowing through each bulb becomes appropriate.
It is preferably at least 00 μF. If the capacitance is too small, the current will be too small. When aging an electrolytic capacitor having a small capacitance, each of C _{1 to} C _n may be configured by a set in which a sufficient number of electrolytic capacitors are connected in parallel. Further, the electrolytic capacitor _C 1 -C _n
The number of bulbs connected in series with each is not limited to two, but may be arbitrarily set to one or more, but preferably so as to withstand the maximum withstand voltage of the aged electrolytic capacitor. Is set in consideration of the withstand voltage of each bulb.

A plurality (n) of such series circuits of the electrolytic capacitor and the bulb are connected in parallel between the terminals d and e. The number n of parallel connections is arbitrarily set in consideration of the type and number of electrolytic capacitors to be aged, the size of a power supply, and the like. The changeover switch 2 is configured to switch between connecting the terminal d to the terminal a or connecting to the terminal b branched from the terminal e. Terminal a is connected to the positive potential side of DC power supply 1. The terminal e is also connected to the negative potential side of the DC power supply 1.

Therefore, when the changeover switch 2 is switched to the terminal a, the DC voltage from the DC power supply 1 is applied to each electrolytic capacitor via the bulb, and when the changeover switch 2 is switched to the terminal b, The series circuit of the electrolytic capacitor and the bulb is configured to be short-circuited.

FIG. 2 is a schematic view showing a part of the aging device for an electrolytic capacitor according to an embodiment of the present invention, which monitors a lighting state of a light bulb. A light receiving element 3 such as a phototransistor is disposed at a position where the light emitted from each bulb is received. Although the light receiving element 3 may be arranged for each of all the light bulbs, each of the electrolytic capacitors C ₁
The light receiving element 3 may be arranged for at least one of the series-connected light bulbs every C _n .
The light receiving element 3 is connected to the detection device 4. Detection device 4
Is composed of, for example, an A / D converter 5, a CPU 6, a memory 7, a display device 8, and the like.

FIG. 3 is a diagram showing the temperature (filament temperature) dependency of the electric resistance of the electric bulb used in this embodiment. As the temperature (filament temperature) increases, the electrical resistance increases.

Next, the operation of the aging device for an electrolytic capacitor having such a configuration will be described.

Firstly, the changeover switch 2 is switched to the terminal a side, applying an electrolytic capacitor to obtain a voltage necessary for reformation, DC voltage of the DC power source 1, for example V ₁ is the terminal d, between e Is done. Thus each bulb, for example L ₁₁ and L ₁₂ current flows, the filament is heated to light by incandescent. However, since each light bulb has a positive temperature coefficient of resistance as shown in FIG. 3, when the energizing current of the light bulb increases, the temperature of the filament increases and the electric resistance increases, so that the current is suppressed. Works. Thus, the electrolytic capacitor, it is possible to suppress in the frame with a current flowing for example, C _1, while suppressing the heat generation of the electrolytic capacitor, it is possible to perform stable aging.

It is preferable that the bulb used has a variable resistance of approximately several tens of ohms (a minute current, near the room temperature of the filament temperature) to 1 kΩ (when the current increases and the filament temperature increases) in the range of the use current. Further, only a light bulb may be used as the current limiter, and it is not always necessary to combine another element such as a resistor. For example, when using a constant current diode or a PTC thermistor as the current limiter, it is necessary to use it in combination with a resistance element etc. in preparation for short-circuit destruction of the electrolytic capacitor during aging. This is preferable because it can cope with short-circuit destruction of the capacitor. Furthermore, if a light bulb is used as a current limiter, it acts to flow a constant current at the start of re-formation, and the current flowing decreases when the re-formation converges when the electrolytic capacitor terminal voltage rises, and the resistance value decreases. Reformation conditions can be achieved.

FIG. 4 shows a non-reformed electrolytic capacitor (25 WV
22000 μF product). When a voltage of 30 V is applied from the DC power supply 1, the terminal voltage of the non-reformed electrolytic capacitor is plotted on the vertical axis, and the voltage application time is plotted on the horizontal axis. When a resistor is used as a current limiter connected in series with the electrolytic capacitor (1 kΩ winding resistor is connected in series with the electrolytic capacitor), when a constant current diode is used (multiple constant current diodes are connected in series and parallel) (A diode circuit board in which a constant current of 10 mA flows is connected in series to an electrolytic capacitor), a PTC thermistor is used, and a bulb is used as in the present embodiment (two 24V-2W bulbs) Are connected in series to an electrolytic capacitor) in each case). The electrolytic capacitor terminal voltage reaches a substantially constant value (final ultimate voltage) after a certain time (rise time). By maintaining the voltage at this voltage for an appropriate time, the electrolytic formation of the electrolytic capacitor is properly performed. In FIG. 4, the rise time of the electrolytic capacitor terminal voltage is approximately 2 times that when a light bulb, a constant current diode, and a resistor are used as current limiters.
5 seconds (t ₁ ), 84 seconds (t ₂ ), and 3 hours (not shown). In the case of the PTC thermistor, an intermediate value between the constant current diode and the resistance was shown. When a light bulb is used as the current limiter, the terminal voltage of the electrolytic capacitor rises more quickly than when a resistor, a constant current diode, or a PTC thermistor is used, and the rise time is shortened. Is shortened.

When a semiconductor device such as a constant current diode or a PTC thermistor is used as a current limiter,
The final voltage of the electrolytic capacitor terminal voltage is DC power 1
However, if a light bulb is used as the current limiter as in the present embodiment, the final attained voltage of the electrolytic capacitor terminal voltage is applied by the DC power supply 1. Since the voltage is almost equal to the voltage, the efficiency is high (see FIG. 4). The leakage current of the electrolytic capacitor can also be made smaller than when the semiconductor element is used as a current limiter.

After the aging is completed, the electrolytic capacitor can be rapidly discharged using the aging device of the present embodiment. When the switch 2 is switched to the terminal b side, the series circuit of the bulb and the electrolytic capacitor is short-circuited, and a current flows through each bulb due to the charging voltage of the electrolytic capacitor, and the bulb is lit.
When the current increases, the temperature of the filament increases, the resistance value increases, and the electric bulb acts to prevent overcurrent and to flow the current in a stable manner, so that the discharge processing of the electrolytic capacitor can be performed accurately. According to the electrolytic capacitor aging device of the present embodiment, a series of processes from aging to discharging of the electrolytic capacitor can be consistently and easily performed.

Further, according to the aging device of this embodiment, the aging state or the discharging state of the electrolytic capacitor can be monitored according to the lighting state of the electric bulb.
As shown in FIG. 2, a light receiving element 3 such as a phototransistor is disposed at a position for receiving light emitted from each bulb. During aging, electrolytic capacitors such as C
_When a break such as disconnection break or short break occurs in ₁ , the bulb L connected in series to the broken electrolytic capacitor
_11, the value of the current flowing through the _{L 12} abruptly changes. Correspondingly, the state of the light of the light bulbs L ₁₁ and L ₁₂ , for example, the luminance also changes abruptly. For example, when short-circuit breakdown occurs, the brightness of the light bulb suddenly increases. Such a change in light of the light bulb is detected by the light receiving element 3. The output signal of the light receiving element 3 is input to the detection device 4. Detection device 4
Then, the output signal of the light receiving element 3 is input to the A / D converter 5 and is converted into a digital signal. The CPU 6 compares the output signal of the A / D converter 5 with a standard output signal pattern stored in the memory 7 to detect whether or not the difference is larger than a predetermined threshold value. It is detected whether or not the time differential value of the output signal of the detector 5 is larger than a predetermined threshold value stored in the memory. If the electrolytic capacitor is destroyed during aging and the brightness of the bulb changes rapidly, the output signal of the A / D converter 5 or the time differential value of the output signal greatly changes, so that the CPU 6 compares the output signal with the standard signal. When the difference from the output signal pattern or the time differential value of the output signal exceeds a predetermined threshold value, the display device 8 displays an abnormality of the electrolytic capacitor. This detects the destruction of the electrolytic capacitor during aging,
In addition, broken electrolytic capacitors can be sorted out.
According to the aging apparatus of the present embodiment, there is no need to perform a separate test for selecting an electrolytic capacitor after aging is completed.

An electrolytic capacitor connected in series with the bulb,
For example, C ₁ is the case consists of the set of connected electrolytic capacitor in a plurality of parallel, it may be culled to determine disconnection breakdown or short breakdown for each set. Also in this case, it is possible to easily detect which set of the electrolytic capacitors has failed, so that the sorting operation can be performed quickly. Further, when the lighting condition of the electric bulb is monitored even when the electrolytic capacitor is discharged, it is possible to determine the completion of the discharge.

The monitoring of the aging state or the discharge state of the electrolytic capacitor depending on the lighting state of the bulb is another configuration as long as a change in current in a series circuit of the electrolytic capacitor and the bulb is detected as a change in light of the bulb. It doesn't matter. In some cases, it is also effective to visually determine the lighting state of the light bulb without using the light receiving element 3.

Although a specific embodiment has been described, the present invention is not limited to the above-described embodiment, as long as the configuration applies a voltage to the electrolytic capacitor via a bulb connected in series to the electrolytic capacitor.

[0034]

As described above, when an aging voltage is applied to an electrolytic capacitor via a bulb connected in series with the electrolytic capacitor, a resistor, a constant current diode, a PTC thermistor, or the like is used as a current limiter. The rise time of the terminal voltage of the electrolytic capacitor can be greatly reduced, and the aging process of the electrolytic capacitor can be performed in a short time.

Furthermore, the electrolytic capacitor aging apparatus of the present invention can be used for rapid discharge after aging, so that a series of processes from aging to discharging of the electrolytic capacitor can be performed consistently.

In addition, the aging state of the electrolytic capacitor can be monitored by the lighting state of the electric bulb, and the destruction of the electrolytic capacitor during aging can be detected. It will be easier. Thereby, the production process can be shortened, and the production cost can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic circuit diagram of an aging device for an electrolytic capacitor according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a part for monitoring a lighting state of a light bulb of the aging device for an electrolytic capacitor according to an embodiment of the present invention.

FIG. 3 is a graph showing temperature dependence of electric resistance of a light bulb used in one embodiment of the present invention.

FIG. 4 is a graph showing a voltage application characteristic of an unreformed electrolytic capacitor.

[Explanation of symbols]

1 DC power source 2 changeover switch 3 light receiving element 4 detector 5 A / D converter 6 CPU 7 memory 8 display device _{C 1, C 2, ~,} C n electrolytic capacitor _{L 11, L 12, L 21} , L 22, ~ , L _n1 , L _n2
light bulb

Claims (5)

[Claims] An aging device for an electrolytic capacitor, comprising: a bulb connected in series to an electrolytic capacitor to be aged; and a DC power supply for applying an aging voltage to the electrolytic capacitor via the bulb. An aging device for an electrolytic capacitor, comprising: 2. The aging device for an electrolytic capacitor according to claim 1, wherein the light bulb is an incandescent light bulb. 3. A circuit switching means for disconnecting a circuit consisting of the electrolytic capacitor and the bulb connected in series from the DC power supply and short-circuiting both ends of the circuit, wherein the DC power supply passes through the bulb via the bulb. 2. The electrolytic capacitor according to claim 1, wherein after applying an aging voltage to the electrolytic capacitor, the circuit switching means short-circuits a circuit including the electrolytic capacitor and the bulb connected in series to discharge the electrolytic capacitor. Aging device for capacitors. 4. The aging device for an electrolytic capacitor according to claim 1, further comprising means for detecting the light intensity of the light bulb, and monitoring an aging state based on the light intensity of the light bulb. 5. The method according to claim 1, further comprising the step of detecting a breakdown of the electrolytic capacitor while applying an aging voltage to the electrolytic capacitor via the bulb based on an output signal of the light intensity detecting means. The electrolytic capacitor aging device according to claim 4.