JPS5848633B2 - Battery voltage monitoring system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention divides a large number of electrolytic cells arranged in series into two or more groups, and monitors the voltage difference between each group, thereby detecting abnormalities in any one of the electrolytic cells. Concerning how to detect.

Furthermore, a large number of electrolytic cells arranged in series are divided into two or more equal groups, and a bridge circuit is constructed in which the voltages of 20 series-connected groups are used as two measurement elements. The present invention relates to a method for detecting an abnormality in an electrolytic cell by monitoring fluctuations in a DC balance current in a bridge circuit that occurs when one of the electrolytic cells is abnormal.

Furthermore, a large number of electrolytic cells arranged in series are divided into two or more groups of equal number, and a bridge circuit is constructed in which the voltages of two series-connected groups are used as two measuring elements. The present invention relates to a method for detecting an abnormality in any electrolytic cell by having a variable resistor in the circuit that can normally make the DC balanced current zero, and when one of the electrolytic cells is abnormal, the DC balanced current is no longer zero.

Industrial electrolytic cells generally have an electrolysis voltage of 2 to 1 per tank.
It is 0 volts.

Therefore, the price of the rectifier can be reduced as much as possible by connecting a large number of these electrolytic cells in series, increasing the terminal voltage to about 100 to iooo volts, increasing the secondary voltage of the rectifier, and lowering the amount of DC current. It will be done.

In such a large number of industrial electrolytic cells connected in series, it is expected that a major accident will occur if any one of the electrolytic cells malfunctions.

For example, in industrial electrolytic cells, the distance between the two electrodes is made as narrow as possible in order to lower the electrolysis voltage as much as possible.

Therefore, there is a risk that the two poles will come into contact with each other, resulting in a short circuit and burnout.

Additionally, there is a risk that the insulation between the two electrodes will break down and cause burnout.

In addition, there is a risk that the insulation between the electrolytic cell and the ground may be destroyed and burnt out.

In addition, the liquid supply becomes uneven, and there is a risk that current will be concentrated in a specific location, causing heat generation.

In addition, there is a risk that electrolyte leaks from one of the electrolytic cells, causing a large current to flow between the electrolytic cell and the main body, resulting in burnout.

Various other accidents can be expected, but in general in electrolyzers,
Since a large current of 100A to 100KA is constantly flowing, when an abnormality occurs in these electrolytic cells, the large current concentrates locally, resulting in a major accident such as burnout.

Therefore, it is absolutely necessary to detect these abnormalities quickly and with high sensitivity to prevent the accident from spreading, for example by turning off the power.

Commonly used detection methods include measuring the voltage between the terminals of each battery case, and tripping when the terminal voltage and/or current of the rectifier fluctuates beyond the upper and lower limits. There is.

For example, how to measure the voltage between the poles of each battery case, etc.
It is common practice to measure the voltages of all about 60 electrolytic cells for producing caustic soda using the mercury method, but this method is generally expensive because of the large number of electrolytic cells.

Moreover, in electrolytic cells, the stress current is often intentionally varied, so the accompanying fluctuations in cell voltage are calculated and corrected.
It quickly becomes complicated and expensive, as it requires a computational mechanism.

Also, although it is cheap and easy to measure the fluctuations in the terminal voltage and current of the rectifier, the terminal voltage of the rectifier is
ooo volts, whereas the voltage of one electrolytic cell is 3
It is normal that the voltage is about 5 to 5 volts, so even if the voltage is 1 to 5 volts,
Even if one electrolytic cell shorts and the voltage drops to zero, the effect on the terminal voltage of the rectifier is small and difficult to detect due to the buffering effect of the other electrolytic cells.

Furthermore, when intentionally varying the charge current of the electrolytic cell, it is necessary to constantly vary the upper limit contact that trips, which is insufficient and may cause malfunctions.

In contrast, the method of the present invention is inexpensive, simple, and extremely insensitive to conscious changes in the electrolytic cell's stress current, and is extremely sensitive to abnormalities in any of the electrolytic cells. You can quickly take measures such as tripping the power supply.

The principle of the present invention is that a large number of electrolytic cells arranged in series are first
Figure 1 shows the case of dividing into two groups. .

1 is a rectifier, ■ is an electrolytic current, and E1tE2 is an electrolytic voltage of two groups.

By monitoring E1-E2-ΔE1, an abnormality in one of the electrolytic cells is detected.

If the groups are divided so that E1=E2, even if the normal electrolytic current is intentionally varied and E1 and E2 vary, ΔE1=0.

Therefore, ΔE1 to 0 will be obtained only when there is an abnormality such as a short circuit in one of the electrolytic cells.

Generally, the specific resistance of each electrolytic cell is different, so
vEz, but if E1=E2, under normal conditions it will be △E1 character 0 even if ■ changes.

Generally, the electrolysis voltage per electrolytic cell is 1 to 5 volts, so if any electrolytic cell becomes abnormal, ΔE will fluctuate by about 1 to 5 volts, so only the abnormality can be detected.

As is clear from the above explanation, if the number of electrolytic cells is too large or the variation in the specific resistance of the electrolytic cells is too large, the variation in △E0 during normal times will be quite large, making it difficult to detect the difference from abnormal times. In such cases, it is preferable to divide the large number of electrolytic cells arranged in series into three or more groups, as this will reduce the variation in ΔE during normal operation and increase detection sensitivity. .

To measure the voltage difference between groups, it is best to construct a bridge circuit.

A diagram of the principle in the case of two groups is shown in FIG.

El t E2 t I is the same as in FIG. 1, and 2 indicates the monitoring system.

R1t R2 t r'1, represents a resistance, r0 represents a variable resistance, and i1, 1 2 t 1'1 represents a current.

E1, E2 where El, E2 are two measuring elements
A bridge circuit consisting of R+ tR2 * r, r is constructed, and the DC balance current i/1 and/or DC voltage difference i'
By detecting the fluctuation of 1×r'1, it is detected by monitoring that an abnormality has occurred in any of the electrolytic cells.

Rl tR2 is selected so that 12 1 11 <1.

Divide the groups so that E2 is in El, and adjust variable resistor r1 so that i'1 is 0, which is preferable if R1 = R2, which is jl-shaped 0, and correct the imbalance between E1 and E2 during normal operation. Absorption is preferred.

r/ may be a variable resistor for sensitivity adjustment.

Measurement terminals may be taken out from both ends of r/ and connected to various detection devices.

For example, a bias constant voltage device may be connected and a constant voltage may be applied to the circuit so that even if i'1 is reversed from positive to negative, a positive signal can be generated.

In addition, it is connected to the input/output converter, and furthermore, the signal, reception indicator,
For example, it may be equipped with a scanner, a recorder, etc.

It can also be connected to an alarm device and/or a rectifier power supply breaker to prevent serious accidents.

FIG. 3 shows a circuit diagram when a large number of electrolytic cells connected in series are divided into three or more groups.

Detect fluctuations in the DC balance current such as i'1, 1 '2 t 1 'a, i'1, r'1, i'2, r'2
, i'3·r/3, etc., it can be easily inferred that it is sufficient to detect fluctuations in the DC equilibrium potential difference.

In this way, by easily and reliably detecting an abnormality in one of the electrolytic cells, it is possible to not only prevent serious accidents, but also to further reduce the distance between the poles in the electrolytic cell.
By further reducing the amount of liquid supplied, increasing the number of electrolytic cells arranged in series, increasing the terminal voltage of the rectifier, and lowering the terminal current, it is possible to make the rectifier equipment cheaper.

In addition, the current capacity of one electrolytic cell can be safely increased, and various economic effects are extremely large.

Such monitoring systems include electrolytic cells for producing caustic soda using the mercury method, electrolytic cells for producing caustic soda using the diaphragm method, electrolytic cells for producing caustic soda using an ion exchange membrane, and electrolytic cells for producing caustic soda using an ion exchange membrane. It can be widely used in electrolytic cells for producing nitrile, electrolytic cells for various types of plating, electrolytic cells for refining copper, nickel, etc., electrolytic cells for water, various types of molten salt electrolytic cells, etc.

Example 90 bipolar electrolytic cells for producing caustic soda, each divided into an anode chamber and a cathode chamber, were connected in series using a cation exchange membrane.
When a current of 3.5 KA is applied, the voltage difference between both ends is 36
It was 0 volts.

These electrolytic cells were divided into two groups of 45 cells each, and the circuit shown in FIG. 2 was constructed.

R1 *R2 were each 150 ohms and r was 100 ohms.

r' was a 10 ohm variable resistor.

By adjusting the variable resistance of r1, i'l during normal operation was made zero.

Then, take out the voltage difference between both ends of r/1 as a measurement terminal E
1-E2 A circuit was constructed so that the rectifier current would be cut off in the event of a fluctuation of 2±1.0 volts or more.

[Brief explanation of drawings]

1 and 2 are circuit diagrams showing the principle of the present invention. FIG. 2 is a circuit diagram showing an embodiment of the present invention, and is a circuit diagram when the electrolytic cells are divided into two groups. FIG. 3 is a circuit diagram showing an embodiment of the present invention, and is a circuit diagram when the electrolytic cells are divided into three or more groups. 1... Rectifier, 2... Monitoring system,
E, E2, E3tEn... Electrolytic voltage, R 1
t R 2... Resistance, ■... Electrolytic current, r1jr2tr3... Variable resistance, i1?
12 tl3 ylH... Current.

Claims (1)

[Claims] 1. A method for detecting an abnormality in any electrolytic cell by dividing a large number of electrolytic cells arranged in series into two or more groups and monitoring the difference in voltage between each group. 2 A large number of electrolytic cells arranged in series are divided into two or more groups, and a bridge circuit is constructed in which the voltages of two directly connected groups are used as two measuring elements. A method of detecting an abnormality in an electrolytic cell by monitoring the fluctuation of the DC balance current in the bridge circuit that occurs when the cell is abnormal. 3 Divide a large number of electrolytic cells arranged in series into two or more groups of equal number, build a bridge circuit that uses the voltages of two series-connected groups as two measuring elements, and always A method of detecting an abnormality in one of the electrolytic cells by having a variable resistor in the circuit that can reduce the DC balance current to zero, and when one of the electrolytic cells has an abnormality, the DC current is no longer zero.