JPS62103381A - Electrolytic corrosion preventive device - Google Patents

Abstract

PURPOSE:To electrolytically protect a body to be protected day and night for a long period of time by respectively electrically connecting the anode of a solar battery and the cathode of a reverse blocking type semiconductor element to a galvanic anode and the cathode and anode thereof to the body to be protected. CONSTITUTION:An electrolytic corrosion preventive device is constituted by electrically connecting the anode of the solar battery 1 and the cathode of a diode 2 as the reverse blocking type semiconductor element provided in paral lel therewith to the galvanic anode 3 embedded in the ground 4 and electrically connecting the cathode of the solar battery 1 and the anode of the diode 2 to a steel pipe 5 which is the body to be protected and is embedded in the ground 4. The corrosion preventive current generated by the solar battery 1 in the day time flows out into the ground 4 then into the steel pipe 5 from which the current returns to the solar battery 1. On the other hand the current generated by the electromotive force based on the potential difference in the night time flows in the route of the anode 3 the ground 4 the steel pipe 5 the diode 2 the anode 3. The steel pipe 5 is thereby electrolytically protected efficiently day and night.

Description

[Detailed Description of the Invention] [Industrial Application Fields] Does this invention use solar cells as a power source? The present invention relates to an electrolytic corrosion protection device, and particularly to an electrolytic corrosion protection device that uses a solar cell and a submerged anode in combination.

[Prior Art] Conventionally, this type of cathodic protection device has been disclosed in which the anode of a solar M pond is directly connected to an insoluble electrode, and the cathode is connected to an object to be protected. (For example, in 1977-
Public No. 39450! F3) Also, connect the anode of the solar cell to the insoluble electrode via the positive terminal of the battery,
A device is disclosed in which the cathode is connected to the object to be protected from corrosion via the negative terminal of the battery.

In other words, the current due to the electromotive force of the solar cell is Kazushi hatch ζ
Corrosion protection is achieved by storing the output current of this battery in the form of corrosion protection current that flows into the object to be protected through the insoluble electrode. (An example is Utility Model Application Publication No. 57-125771.) [Problem q that the invention attempts to solve] Considering the above-mentioned conventional solar power, the lightning corrosion protection boiling tυζ where 1st cell is 7I9, the former (1 ) HR has not been put into practical use because there is a risk that it may not be possible to obtain a sufficient Q-value of anti-corrosion current on rainy or cloudy days, and there is a fatal problem that no current is generated especially at night. is the current situation.

On the other hand, the latter device stores the f4 current generated by the solar cell in the battery for one day and then uses it as the anti-corrosion current, so it has the advantage of being able to supply the anti-corrosion current even when the current generated by the solar cell fluctuates at night. However, with this method of using batteries, the life of the battery is short, less than a few years, so if you use long-term lightning strikes like cathodic protection equipment, you will need to replace the battery with a new one every time the battery's life runs out. It would have to be replaced, and the cost of replacement would be enormous.

In addition, in order to maintain the battery in good condition, maintenance and inspections are required at least several times a year, which poses various problems both economically and technically.

The present invention provides a cathodic protection device that can eliminate the problems listed in item H of conventional cathodic protection devices using solar cells as a power source and can prevent metal corrosion over a long period of time. [Means for solving the problem] In order to achieve this object, the present invention has the following various configurations and 1-.τ.

That is, the M corrosion protection H according to the first invention connects the seven nodes of a solar cell and the cathode of a reverse mesh semiconductor element installed in parallel with the solar cell to the N anode. It is constructed by connecting the cathode of the solar cell and the anode of the reverse protection type semiconductor element to an object to be protected from corrosion.

Further, the cathodic protection device according to the second invention includes an electromagnetic device that connects the anode of the solar cell to a galvanic anode, connects the cathode to the object to be protected, and is connected to be driven by the current generated by the solar cell. It is constructed by connecting the relay's b contact (a contact that opens when current flows through the electromagnetic relay coil and closes when the current does not flow) in parallel with the battery.

[Function] With the above configuration, first, the galvanic anode is connected to the anode of the solar cell, and the object to be protected is connected to the cathode. A current generated by the electromotive force flows from the current anode through the electrolyte to the surface of the object to be protected from corrosion, thereby protecting the object from corrosion.

Next, at night when sunlight cannot be irradiated, a current flows due to the electromotive force caused by the potential difference between the galvanic anode and the object to be protected, flows onto the surface of the object to be protected, and protects the object from corrosion. become.

By the way, if a solar cell and a galvanic anode are connected in series to the object to be protected to form a cathodic protection circuit, the internal resistance of the solar cell is quite large, so the galvanic anode will not generate current at night when the solar cell does not generate current. Almost no current flows due to the electromotive force between the anode and the object to be protected, and therefore it is difficult to achieve corrosion protection.

However, in the first invention, reverse blocking 1. I: type semiconductor element is
In addition, in the second invention, since the relay BTA which is operated by the R current of the solar cell is connected in parallel to the solar cell so as to act as a bypass, the anti-corrosion current is mainly caused by the electric resistance. Small reverse fu11. The current flows through the circuit via the IF type semiconductor element or the b contact of the electromagnetic relay, and even a relatively small potential difference between the galvanic anode and the object to be protected generates enough current to protect the object from corrosion. Be able to flow.

On the other hand, the above-mentioned reverse-blocking semiconductor element or the parallel circuit with the solar cell including the b contact of the electromagnetic relay forms a short circuit to the solar cell, but the reverse-blocking semiconductor element For the opposite direction, it is 11J. :: If the short-circuit current of the solar cell is ignored, the short-circuit current will not flow.

Furthermore, while the solar cell is generating current, the current from the solar cell flows through the coil of the electromagnetic relay and the B contact is open, so a short circuit in the solar cell will not occur.

[Example] The present invention will be described below based on an example shown in the drawings.

FIG. 1 and FIG. 2 are explanatory diagrams showing an embodiment of the invention of v.1 when a reverse blocking type semiconductor element is used.

In Figure 1, (1) is thick lJ! battery, (2) is the diode, (3) is the galvanic anode, (4) is the earth, (5)
) is a steel pipe as the object to be protected against corrosion.

The anode of the solar cell (1) is between current F! +(3), the cathode is electrically connected to the steel pipe (5) buried in the ground (4).

Further, the anode of the diode (2) is electrically connected to the steel pipe (5), and the cathode is electrically connected to the flow TL anode (3), forming a parallel circuit with respect to the solar cell.

The name of configuring the cathodic protection circuit in this way and the daytime solar electric oil (
While I) is generating lightning, the anti-corrosion current flows from the 7 nodes of the (+) solar cell through the galvanic anode (3) to the earth (4).
The water flows out into the steel pipe (5), which is the object to be protected from corrosion, and passes through the electrical circuit to the cathode of the solar cell (1), thereby protecting the steel pipe (5) from corrosion.

In addition, at night when the solar cell does not generate current, the current generated by the electromotive force based on the potential difference between the steel pipe (5) as the object to be protected and the galvanic anode (3) flows from the galvanic anode to the earth ( 4), flows into the steel pipe (5), and flows into the diode (
2) to prevent corrosion of the steel pipe (5) by immersing the electric circuit so that the current returns to the anode (3) via the galvanic current anode (3).

FIG. 2 shows an embodiment in which a reverse blocking three-terminal thyristor (6) is used as the reverse blocking semiconductor element.

In FIG. 2, components other than the reverse blocking three-terminal thyristor (6) and the resistor (7a) inserted in the gate circuit of this reverse blocking three-terminal thyristor are designated by the same symbols as in FIG. 1.

In FIG. 2, the flow of anti-corrosion current while the thick R4 battery (1) is generating electricity is the same as in FIG.

When the solar cell (1) does not generate current, the galvanic anode (
3) and the steel pipe (5) due to the electromotive force, a resistance (
7a), the gate trigger current stagnates and makes this reverse blocking three-terminal thyristor conductive, thereby forming a sacrificial protection circuit.

The anticorrosion current in case 2 is from galvanic anode (3) to earth (4)
It flows into the steel pipe (5) via the reverse blocking three-terminal thyristor, flows through the electric circuit to return to the galvanic anode, and protects the steel pipe (5) from corrosion.

Further, as the reverse blocking three-terminal semiconductor device used in the present invention, in addition to the thyristor described in -H, a gate turn-off thyristor or an electrostatic induction thyristor can be used.

FIG. 3 is an explanatory diagram showing an embodiment of the second invention.

In Fig. 3, a resistor (7b), an electromagnetic relay (8), and a coil (8a) included in this electromagnetic relay, and a b that operates to open when Mt current flows through this coil and close when no current flows. Contact (Rh) L: / outside, 7A
It is indicated by the same reference numerals as in Figure I.

The anode of the solar cell (+) is electrically connected to the galvanic anode (3), and the cathode is electrically connected to the All tube (5) buried in the ground (4).

Further, the coil (8a) of the electromagnetic relay (8) has a resistance (7
b) is connected in parallel with the electric wire connecting the solar cell (1) and the galvanic anode (3).

With this configuration, while the solar cell (+) is generating current, the anti-corrosion current flows from the anode of the (+) solar cell through the galvanic anode (3) to the ground (4), and is covered with It flows into the tJA pipe (5) which is a corrosion protector, protects this steel pipe, and returns to the cathode of the thick R4 battery (1>).

At this time, since the b contact (8h) of the electromagnetic relay (8) is open, the short circuit current of the solar cell (1,) does not flow through the b contact.

In addition, when the solar cell is not generating W current, the b contact (8b) of the electromagnetic relay (8) is closed, and the current anode (3
) and the steel pipe (5) A current generated by an electromotive force based on the difference in ohms flows into the steel pipe (5) via the earth (4), protects the steel pipe from corrosion, and activates the electromagnetic relay ( The current flows through the b contact (8h) of 8) and returns to the galvanic anode (3>).

Furthermore, a plurality of electromagnetic relays (8) can be connected in parallel to reduce the contact resistance of the b contact.

The galvanic anodes used in this invention include magnesium alloy anodes, aluminum alloy anodes, and zinc alloy anodes. Or, or
Multiple pieces of the same shape can be connected in parallel.

[Effects of the Invention] As explained above, in this invention, a galvanic anode is connected to the object to be protected via a solar cell, and the solar cell and the seedling row are connected to the +l-7 semiconductor element or the solar cell. Since the B contact of the electromagnetic relay is connected to the contact B of the electromagnetic relay, which is driven by the current generated by the battery, while the solar cell is irradiated with light and generates current, the current generated by the solar cell is passed through the current anode. It is possible to prevent corrosion by flowing into the surface of the object to be protected, and there is no need for light irradiation. When the pond does not generate an ILF current, the current from the current anode does not pass through the solar cell, which has a large electrical resistance, but is connected to a reverse blocking semiconductor element with a small electrical resistance or an electromagnetic relay in parallel with the solar cell. Since the current flows through the contacts, even a relatively small potential difference between the galvanic anode and the object to be protected can provide sufficient electrical current required for corrosion protection.

Moreover, the inverted double gate type semiconductor element installed in parallel to the solar cell has unidirectional conductivity, and the b contact of the electromagnetic relay installed in parallel to the solar cell is unidirectionally conductive. Since the circuit is open while the battery is generating current, no short circuit is formed to the solar cell and no short circuit current flows.

Since the galvanic anode continues to generate a predetermined current after being installed, it does not require any special maintenance and can protect the battery from corrosion over a long period of time.

As described above, according to the present invention, during the daytime when the solar cell can receive light beams, the current from the solar cell protects the object to be corroded, and before night when light beams cannot be irradiated, the galvanic anode protects the object. Since the object to be corroded is sufficiently protected from corrosion by the Wl flow generated by the electric fff difference between the object and the object to be corroded, the object to be corroded can be protected from corrosion for a long period of time even in a place where there is no commercial power supply.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 are explanatory diagrams showing an embodiment of the first invention. FIG. 1 is an explanatory diagram of the case where a V-auto is used as the reverse blocking type semiconductor element, and FIG. 2 is a detailed explanatory diagram of the present invention when a three-terminal thyristor is used as the reverse blocking type semiconductor element. be. FIG. 3 is an explanatory diagram showing a second embodiment of the present invention.

Claims (1)

[Claims] 1. An anode of a solar cell and a cathode of a reverse blocking semiconductor element provided in parallel with the solar cell are connected to a galvanic anode, and the cathode of the solar cell and the reverse blocking semiconductor element are connected to a current anode. A cathodic protection device characterized in that an anode is connected to an object to be protected. 2. The electrolytic protection device according to claim 1, wherein the reverse blocking semiconductor element is a diode. 3. The electrolytic protection device according to claim 1, wherein the reverse blocking semiconductor element is a reverse blocking three-terminal thyristor. 4. The anode of the solar cell is connected to the current anode, the cathode is connected to the object to be protected, and the b contact of the electromagnetic relay connected to be driven by the current generated by the solar cell is connected to the solar cell. A cathodic protection device characterized by being connected in parallel.