RU1770929C - Three-component electric field meter - Google Patents

Abstract

Usage: in the field of physical oceanology, in particular in measurements of constant and slowly changing electric fields in the sea. SUMMARY OF THE INVENTION: A three-component electric field meter comprises corps, electrodes, hydraulic channels, and a hydraulic key. New in the device is the implementation of a spherical cavity in the housing and the execution of a hydraulic key in the form of an elastic elastic shell connected by a barbell with a pulsating pressure source. A strain gauge is mounted on the spherical surface of the cavity, connected to the recording unit and through a timer with a pressure source drive. In the injection stroke, the shell fills the cavity and isolates the electrodes from each other. In the vacuum cycle, the electrodes are contacted through a low resistance circuit. 2 ill.

Description

The invention relates to the field of physical oceanology, in particular to the measurement of constant

slow-moving electric fields in the sea, and can be used to study the spatio-temporal structure of electric fields in the ocean.

A three-component primary transducer is known for studying the vertical structure of electric fields in the sea, consisting of a housing with electrodes and hydraulic channels and a hydraulic key in the form of a cylinder with a contact cavity located in its side surface.

The disadvantage of these devices is the low accuracy of the measurements, since the electrodes are spaced in space and are in different physicochemical conditions, and

intrinsic EMF and their drift are not controlled.

The closest technical solution is a three-component electric field sensor in the marine environment, containing a cylindrical hollow dielectric casing, on the inside of the first base of which on a circle of radius r, the center of which coincides with the center of the base, three measuring distances are installed at angular distances of 120 ° the troda and three hydro channels, which are radially mounted at an angle of 120 °, open to the environment by external messengers, and secured in the case against internal measuring channels by internal messengers electrodes.

The fourth hydrochannel is installed in the center of the base of the body and the external end is in communication with the environment, and in

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a reference electrode mounted to its inner end; Inside the casing there is a hydraulic key in the form of a cylinder, at the base of which, facing the measuring electrodes, there is a contact cavity extending to its side surface, and at a distance r from its center, an additional cavity and a through channel are made on the base facing the measuring electrodes, connected an additional cavity with the center of the opposite base of the hydrokey and the open end of the fourth hydrochannel. The hydraulic key is connected to the axis of the mechanical drive passing through the center of the housing base,

When the hydrokey is rotated, each of the three measuring electrodes is connected in series with the corresponding hydrochannel and then through the through channel directly with the fourth reference electrode, which eliminates the parasitic effect of the intrinsic EMF electrodes.

This device does not have a sufficiently high measurement accuracy, which is associated with a low sensitivity and a high level of interference from electrification during friction.

Indeed, the sensitivity of the electric field meter is proportional to the length of the measuring base, which. in turn, it is limited by the condition that the resistance of the hydrochannels should be much less than the resistance of the hydrokey in the closed state. In our case, this is leakage resistance along the gap between the side surface of the rotating hydraulic key and the housing. Practice has shown that this leakage resistance typically ranges from a few hundred ohms to units of ohms. During operation, the side surfaces are worn away, beats appear, and leakage resistance decreases further over time, limiting the possibility of using long hydro channels.

A high level of interference is associated with the presence of rubbing surfaces. In this case, the device parts are electrified up to the occurrence of microdischarges that interfere with the measurements,

The aim of the invention is to improve the accuracy of measurements.

In FIG. 1 is a perspective view showing an example of a practical implementation of the device, and FIG. 2 - device housing and hydraulic key.

The three-component electric field meter comprises a supporting body 1, where there is a container with registration equipment, a rack 2, a meter body 3;

hydro channels 4-9. The housing 3 is made in the form of a cube, in the faces of which the ends of the orthogonal hydrochannels 4-9 are attached.

Electrodes 10-14 (sixth electrode on

Fig. 2 (not shown) are mounted in the housing 3 near the ends of the hydrochannels 4-9 with a protrusion into the hydrochannels 4-9. In the center of the housing 3, a spherical cavity 15 is made, into which the elastic shell 16 is inserted, made

for example, of thin rubber, the cavity of the sheath 16 is connected by a hose 17 to a pulsating pressure source 18.

Hydrochannels 4-8 are made in the form of pipes open from the ends.

Hydrochannel 9 is made in the form of a pipe segment with an outlet in pin 2. The pulsating pressure source 18 is a piston-type push-pull hydraulic pump closed to a fluid reservoir and providing a sequential pumping stroke and a vacuum stroke. Shell 16, hose 17 and hydraulic pump are filled with water. In FIG. 2 dashed line indicates the position

shell 16 in a filled state, and in a solid curve the position of shell 16 in a deflated state. On the surface of the spherical cavity 15, a strain gauge 19 is mounted, connected to the recording unit 20 and to the drive 22 of the source 18 through a timer 21. Electrodes 10-14 are also connected to the recording unit 20.

As the strain gauge 19, you can use, for example, a spring-loaded

contact pair or semiconductor film strain gauge. The registration system employs well-known methods of synchronous detection using the signals of the strain gauge 19 as reference.

The device operates as follows.

The meter is placed in the sea; for example, they are fixed at the bottom. In this case, the axes of the hydrochannels 4–9 form an orthogonal coordinate system, for example, channels 5–6 — the X axis, channels 7–9 — the Y axis, channels 4–9 — the Z axis. Corresponding information channels form pairs of electrodes 10-11, 1213, 14 and the sixth electrode.

When the drive 22 of the source 18 is turned on, the shell 16 is filled, enveloping the surface of the spherical cavity 15. As soon as the excess pressure on the surface of the cavity 15 reaches a predetermined value that determines the degree of electrical isolation of the hydraulic channels 4-9, the strain gauge 19 will give signals to the drive 22 with the cessation of cycle injection into block 2C

registration - about the beginning of the measure

starts timer 21. The voltages taken from the pairs of electrodes 10-14 are equal in this cycle to the sum of the potential difference between the open ends of the hydrochannels 4-9 (field in the medium) and the intrinsic EMF of the electrodes 10-14.

After a predetermined time determining the duration of the measurement cycle, the timer 21 will give a signal to the registration unit 20 about the end of the measurement cycle and to the drive 22 about the beginning of the rarefaction cycle. The hydraulic pump pumps water from the shell 16. providing direct electrical contact between the electrodes 10-14. The shell 16 is compressed, and the strain gauge 19 provides a signal to the hydraulic pump drive 22 to stop the rarefaction cycle, to the recording unit 20 to start the comparison cycle and starts timer 21 again, which determines the duration of the comparison cycle.

In this cycle, the voltages removed from the pairs of electrodes 10-14 are equal to the intrinsic EMF of the electrodes 10-14. An external electric field enters into these signals as many times weakened as the resistance between the electrodes located near each other 10-14 is less than the resistance of the hydrochannels 4-9, in practice, hundreds of times. thus, it has practically no effect on the measurement results.

Next, the timer 21 signals the end of the comparison clock to the recording unit 20 and starts the hydraulic pump in the pressure boosting mode, and thus the complete measurement cycle is completed. Subsequently, all processes are cyclically repeated. The voltages taken from the pairs of electrodes 10-14 are pulse signals, the synchronous detection of which gives

the desired electric field in the medium, regardless of the intrinsic EMF of the electrodes 10-14 and their drift.

In the measurement cycle, the shell 16 provides a very high degree of electrical insulation of the electrodes 10-14 (almost to several megaohms), which allows the use of long channels 4-9 and thereby increase the real sensitivity

meter.

The device has no rubbing surfaces and, therefore, there is no interference from electrification during friction.

Thanks to this, the device has

Claims (1)

greater sensitivity, noise immunity and, accordingly, greater accuracy of the measurement results. SUMMARY OF THE INVENTION A three-component electric field meter containing a dielectric body in which a cavity is made in the form of a body of revolution, six hydrochannels, four of which are mutually perpendicular in one plane, and two others - perpendicular to this plane, and six measuring electrodes, and the hydrochannels are fixed on the housing and connected to the cavity inside the housing, and the measuring electrodes are fixed in the housing with a protrusion into the hydrochannels and connected to the recording unit, characterized in that, in order to increase the accuracy of measurements, an elastic shell is introduced into the cavity, connected by a hose to the source pulsating pressure, and in the cavity on the inner surface of the housing a strain gauge is installed, connected to the registration unit and through a timer to the drive of the pulsating pressure source. to the electrodes