JP3179385B2 - Lead battery replacement time recognition method and uninterruptible power supply using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lead battery replacement time recognition system and an uninterruptible power supply using the same.
More particularly, the present invention relates to a lead battery replacement time recognition method for predicting the life of a lead battery at the time of trickle charging in an uninterruptible power supply and recognizing its replacement time, and an uninterruptible power supply using the same.

[0002]

2. Description of the Related Art In a conventional uninterruptible power supply, there is a method of recognizing a replacement time of a lead battery by, for example, performing temporary discharge or temporary charge for a certain period of time and predicting a life from a voltage fluctuation value at that time. The life expectancy from the temporary charging and the voltage fluctuation value may be manually performed by an operator or performed by a computer.

FIG. 4 is a circuit diagram showing a conventional lead battery replacement time recognition method by a computer. In FIG. 4, the lead battery 21 has a normal charging circuit 3, a discharging circuit 4,
Connected to the inverter 5 via the power supply to form an uninterruptible power supply.

When estimating the life of the lead battery 21, the microcomputer 7 instructs the temporary discharge circuit 6 to temporarily discharge the lead battery 21 for a predetermined time set by the timer 9. A discharge voltage value of the lead battery 21 when temporarily discharged,
The temperature detected by the thermistor TH is input to the A / D converter 8. The microcomputer 7 reads the voltage corrected by the temperature at certain time intervals, and
The life expectancy. As a result, when it is determined that the service life has expired, the transistor 10 is operated to activate the LED 14.
Is turned on to indicate the battery replacement time.

[0005]

In the above-mentioned prior art, the temporary discharge of the lead battery is performed for a certain period of time, and the life is recognized based on the voltage drop at that time or the voltage fluctuation value at the time of transition to the temporary discharge. In addition, there is a problem that a complicated circuit such as a computer is required in order to recognize the life based on the potential change gradient. Alternatively, there is a problem that manual operation and judgment by a person is required.

According to the present invention, there is provided a lead battery replacement time recognition method capable of recognizing a replacement time of a lead battery at the time of trickle charging in an uninterruptible power supply without requiring human intervention or a complicated circuit such as a computer. An object of the present invention is to provide an uninterruptible power supply using the same.

[0007]

[0008]

[0009]

A first lead battery replacement time recognition system according to the present invention is a lead battery replacement time recognition for recognizing a replacement time based on a trickle charge life of a lead battery used in an uninterruptible power supply. A method, wherein an electrolytic capacitor under the same temperature environment as the lead battery, and a ripple current such that the life characteristic of the electrolytic capacitor becomes substantially the same as the life characteristic of the lead battery for the electrolytic capacitor. A ripple generating circuit, a comparator for comparing a voltage value between both ends of the electrolytic capacitor with a reference voltage value, and a result of the comparison by the comparator, when a voltage value between both ends of the electrolytic capacitor is smaller than a reference voltage value. Is O
FF, a transistor that repeats ON or ON / OFF when the voltage value at both ends of the electrolytic capacitor is equal to or higher than a reference voltage value, and turns off when the transistor is OFF,
A battery replacement time display section that lights up when N and blinks when it is repeatedly turned on and off.

In a second lead battery replacement time recognition method according to the present invention, in the first lead battery replacement time recognition method according to the first invention, the reference voltage is set when the replacement time of the electrolytic capacitor has reached its life. And a voltage across the electrolytic capacitor.

A third lead battery replacement timing recognition method according to the present invention is the first or second lead battery replacement timing recognition method, wherein the electrolytic capacitor and the lead battery are stored in the same battery unit. It is characterized by being performed.

The uninterruptible power supply of the present invention is the first uninterruptible power supply of the present invention.
Characterized by using the to third replacement time recognition method of at least one of the lead battery.

The above means focuses on the fact that the life of a lead battery when trickle charging is used in an uninterruptible power supply depends on the ambient temperature, and utilizes the characteristics of an electrolytic capacitor whose life also depends on the ambient temperature. Further, by recognizing the deterioration of the performance of the electrolytic capacitor, it is recognized as the life of the lead battery.

[0014]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a circuit diagram showing an embodiment of the present invention. In the uninterruptible power supply, a part for recognizing the life of a lead battery when trickle charging is used is indicated as a battery replacement time recognition circuit 1. It is the part that is. The lead battery 21 is connected to the inverter 5 via the normal charging circuit 3 and the discharging circuit 4 to constitute an uninterruptible power supply.

The battery replacement timing recognition circuit 1 compares an electrolytic capacitor 22, a ripple generating circuit 11 for constantly generating a ripple current to the electrolytic capacitor 22, and a voltage value at both ends of the electrolytic capacitor 22 and a reference voltage value. It comprises a comparator 12, a transistor 13, and an LED 14 that indicates when the lead battery 21 needs to be replaced. Comparator 1
The reference voltage input to 2 is the voltage at both ends of the electrolytic capacitor 22 when the electrolytic capacitor 22 reaches the replacement time due to its life.

The lead battery 21 and the electrolytic capacitor 2
2 is stored in the battery unit 2.

FIG. 2 is a graph showing the relationship between the temperature and the life of the lead battery at the time of trickle charge. The life of the lead battery 21 is as follows in a temperature range of 10 ° C. to 60 ° C. which is an actual use environment. It can be almost expressed by such a calculation formula.

L = L ₆₀ × 2 ^{(60−T0) / 10} (1 ⁾ (L = life at ambient temperature T0 ° C., L ₆₀ = ambient temperature 6)
(Life at 0 ° C., T 0 = ambient temperature) The estimated life of the electrolytic capacitor 22 can be expressed by the following formula.

L = Lm × 2 ^{(Tm−T0) / 10} × 2γ ^{· {1- (In / Im) 2}} (L = life at ambient temperature T0 ° C., Lm = ambient temperature Tm
C / lifetime at ripple current Im, T0 = ambient temperature, T
m = maximum operating temperature, γ = constant, In = actual ripple current, Im = maximum allowable ripple current at Tm) where the ambient temperature is 60 ° C./the life of the ripple current Im is L ₆₀
Then, the estimated life equation of the electrolytic capacitor 22 at 60 ° C. or lower is L = L ₆₀ × 2 ^{(60−T0) / 10} × 2γ ^{· {1- (In / Im) 2}} , and 2γ ^· Except for In of ^{{1- (In / Im) 2}} , it depends on the electrolytic capacitor to be selected. Therefore, if it is assumed to be a constant and k is assumed, the estimated life of the electrolytic capacitor 22 is as follows: L = L ₆₀ × 2 ^{(60−T0) / 10} × kIn Equation 2

Therefore, comparing Equations 1 and 2, the actual ripple current In is obtained because the ambient temperature environment is the same.
Is adjusted, the estimated life characteristics of the electrolytic capacitor 22 can be matched with the estimated life characteristics of the lead battery 21.

Next, based on the above description, the operation of the embodiment of the present invention will be described in detail with reference to FIGS. FIG. 3 is a graph showing the relationship between the life of the electrolytic capacitor and the input and output of the comparator.

As shown in FIG. 1, the battery replacement timing recognizing circuit 1 includes a ripple for generating a ripple current having a magnitude such that the estimated life characteristic of the electrolytic capacitor 22 becomes substantially the same as the life characteristic of the lead battery 21. A generation circuit 11 is provided.

The ripple generating circuit 11 constantly supplies a ripple current to the electrolytic capacitor 22. As for the voltage across the electrolytic capacitor 22, the ripple is smoothed when the electrolytic capacitor 22 has not reached the end of its life, so that the + side input of the comparator 12 is lower than the reference voltage as shown in FIG. Become. In this case, since the output of the comparator 12 is LOW, the transistor 13 is turned off,
The LED 14 for displaying the battery replacement time remains off.

When the life of the electrolytic capacitor 22 has expired, a voltage higher than the reference voltage as shown in FIG.
Is repeatedly turned ON / OFF, and the LED 14 for displaying the battery replacement time blinks.

In the above description, the lead battery 21 and the electrolytic capacitor 22 are the same in the battery unit 2.
, But may be separated if the temperature condition of the place where the device is installed is the same.

[0027]

As described above, the present invention recognizes the life of a lead battery by comparing the ripple voltage using the life characteristics of an electrolytic capacitor, so that complicated circuits such as human intervention or a computer are required. Is unnecessary, and it is possible to automatically know when to replace the lead battery with a simple circuit.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention.

FIG. 2 is a graph showing the relationship between the temperature and the life of a lead battery during trickle charging.

FIG. 3 is a graph showing the relationship between the life of an electrolytic capacitor and the input and output of a comparator.

FIG. 4 is a circuit diagram showing a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Battery replacement time recognition circuit 11 Ripple generation circuit 12 Comparator 13 Transistor 14 LED 2 Battery unit 21 Lead battery 22 Electrolytic capacitor 3 Charge circuit 4 Discharge circuit 5 Inverter

Claims (4)

(57) [Claims] 1. A lead battery replacement time recognition method for recognizing replacement time based on trickle charge life of a lead battery used in an uninterruptible power supply, comprising: an electrolytic capacitor under the same temperature environment as the lead battery; A ripple generating circuit for generating a ripple current such that a life characteristic of the electrolytic capacitor becomes substantially the same as a life characteristic of the lead battery; and a voltage value and a reference voltage value at both ends of the electrolytic capacitor. When the voltage value at both ends of the electrolytic capacitor is smaller than a reference voltage value, the comparator is turned off, and when the voltage value at both ends of the electrolytic capacitor is equal to or more than the reference voltage value, Is a transistor that repeats ON or ON / OFF, and is turned off when the transistor is OFF, lit when ON, ON, O Replacement time Recognition of the lead battery characterized by having a battery replacement timing display unit flashes when F repeated. Wherein said reference voltage is time to replace Recognition of the lead battery according to claim 1, wherein the electrolytic capacitor is a voltage across the electrolytic capacitor when it reaches the replacement time in life. Wherein the electrolytic capacitor and the lead battery and the replacement timing Recognition of lead battery according to claim 1 or 2, wherein the stored in the same battery unit. 4. An uninterruptible power supply device using the lead battery replacement timing recognition method according to at least one of claims 1 to 3 .