The sensor strength of the electric field (options)
(57) Abstract:The invention relates to electrophysical measurements, in particular for measurements of current density conductivity or electric field strength, and can be used in Oceanography, geophysical surveys, prospecting. The technical result consists in minimizing the distortion of a sensor in the monitoring of the electric field. The technical result is achieved by selecting the shape of the dielectric housing, the rails of which coincide with the lines of force of the field, and the electrodes measuring the potential difference is set perpendicular to the body axis coincide with the equipotential surfaces and connected to each other through the coil of the current transformer. The case can be made in the form of a hollow straight cylinder, the electrodes located inside the housing and communicated with the environment through the waterway, having the form of truncated cones. The case can be made in the form of a hollow cube sealed and equipped with a flat dielectric screens, forming canals in the form of a truncated four-sided pyramids. For embodiments is the choice of the geometrical dimensions. 2 S. p. f-crystals, 2 Il. Isoprodol or the strength of the electric fields in conductive media, and can be used in geophysical, Oceanographic research, including seismology.A known electric field sensor having a system of metal electrodes placed in a conductive medium at a small distance from each other and connected through a matching transformer to the input of the preamp , introduces distortions in the studied electric field whatever small sensor size, which does not ensure a high conversion rate due to technical difficulties, not to ensure optimal coordination on the noise of the electrode system with a preamp.A known electric field sensor, which is free from the last of these shortcomings  . This sensor has an electrode system in the form of two hollow prosteroids separated by a dielectric insert in the cavity of the electrodes is measuring coil, the primary winding of which is connected to the electrodes and contains a few turns; the secondary winding via a decoupling capacitor is connected with the vanishing of the preamplifier. This design helps to ensure optimal coordination of the noise. However, to realize high limit of sensitivity is parallel to the vector of intensity of the studied electric field. In addition, increasing the size of the volume of the electrodes causes a significant distortion of the picture field.Closest to the claimed technical solution is the System response and the measurement of the electric field within a predetermined environment"  (U.S. patent N 3641427, 1972), containing three pairs of electrodes, arranged and structurally arranged so that they form opposite strips of the cube, the outside has a relationship with the environment, and the inner surface is isolated from the external environment. Each pair of electrodes electrically connected to each other via a differential amplifier, having an input impedance equal to the impedance of the environment, to the outputs of differential amplifiers connected the measuring system.However, as with all listed counterparts, ensuring maximum sensitivity and conversion is achieved by the greatest power of the useful signal from the environment and, as a consequence, due to their application in the study of the homogeneous field of higher distortion by increasing the field measurements. The latter is not always desirable, and in some cases unacceptable. First of all, oblastites implemented by the primary Converter, and its measurement area - averaging of the fields will overlap region of homogeneity of the source field. This will lead to incorrect interpretation of measurement results. Furthermore, the area distortion of the primary Converter in the field being studied, does not allow close to place similar or different sensors for complex measurements when several sensors must be placed in a limited volume. This is especially important circumstance in the calibration and metrological testing of sensors. Typically, the reference calibration unilateral field is strictly limited, which should be placed at least two sensor - checked (calibrated) and the reference (control). There may be other situations where the sensor should not introduce distortion in the field being studied or to distort it in a minimum volume, for example, for stealth measurements when the sensor can be detected by such distortions in the source field.The task of the proposed technical solution consists in the reduction to the minimum values of the distortion of a sensor in the monitoring of the electric field.The problem is solved in that in the known sensor tension by electrode, according to the invention the casing is made in the form of a hollow straight cylinder, the electrodes are placed inside the housing is symmetrical about an axis and a Central body and communicated with the environment through the waterway, having the form of truncated cones, and the electrodes are short-circuited through the coil of the current transformer, the ratio of the geometric dimensions selected conditions:
R = 2Rto,
R is the resistance of the medium volume displaced by the probe;
Rkthe resistance of the volume of medium in the streaming channel.In the second variant of the invention the problem is solved in that the known gauge the strength of the electric field, containing dielectric housing made in the form of a hollow cube sealed with a flat metal electrodes on the faces of the cube, and each pair of oppositely spaced electrodes electrically connected according to the invention is further provided with a flat dielectric screens attached to the edges of the cube, forming canals in the form of a truncated four-sided pyramids, through which electrodes is in communication with the external environment, while the smaller pyramid base are supported on the electrodes, the height of the pyramids SEL is smaller base, and electrodes located on opposite faces of the cube, in pairs shorted through the coils of the transformers.The essence of the proposed technical solution is illustrated by drawings, where Fig. 1 is a cross section of a cylindrical sensor with canals, in Fig. 2 is a cross section of the cubic sensor waterway.The sensor (Fig. 1) has a cylindrical dielectric housing 1 is hermetically installed conductive electrodes 2 are located inside the housing symmetrically about the axis and the Central section of the housing 1 and connected to the environment through the waterway 3, having the shape of truncated cones. The electrodes 2 are short-circuited by means of a coil 5 and the current transformer 6.Three-component sensor voltage electric field (Fig. 2) has a dielectric housing 1, made in the form of a hollow cube, all six faces of which there are identical planar conductive electrodes 2, mutually opposite pairs of which are short-circuited to form an electronic system components for field coinciding with the axis of the pair of electrodes. To eliminate the mutual shunting electrodes on all edges of the cube are mounted flat dielectric 5, the image of what atom electrodes 2 are in contact with the external environment through the canals 4, formed by faces of the pyramids. In the cavity of the dielectric cube are matching device 6 three-component measuring system.In the working position sensor is placed in a conductive medium, while the component of the electric field, the axis of which coincides with the axis of the dielectric housing 1, creates a potential difference between the electrodes 2, and the circuit electrode winding matching device electrode current flows.As is known , the permissible distortion of the initial homogeneous field sensor housing of the order of few percent, the size of the field distortion (averaging or measurement) field reach the five dimensions of the sensor. The obvious way to reduce the size of the field distortion due to the reduction of the dimensions of the PM sensor is not always acceptable, as this intensifies sensitivity and reduced conversion factors PP. This contradiction may be resolved with the use of such designs dielectric sensor bodies that are outside theoretically do not cause any distortion of the studied field. If in a conductive medium with a uniform electric field to Deposit the dielectric cylindrical surface right is lindra the surrounding water and its orientation forming parallel to the force lines of the field there is no distortion. The same result will be obtained for entry into the field of the infinitely thin electrodes-of the ends of the cylinder, if the plane will be perpendicular to the power lines, i.e., will coincide with the equipotential surfaces of the source field. When the combination of the ends of the electrodes is filled environment dielectric cylindrical shell source field will remain both inside and outside containment. However, the paragraphs in the specified form has no practical significance. Real design PP should only externally to match the shape of a straight cylinder or any direct prism, since we are interested in the distortion-free field just outside of the housing. The thickness of the end electrodes and walls of the dielectric housing may be any, and the cavity is sealed, if the inside between the electrodes include a resistor with resistance equal to the resistance of extruded PP volume of water. For direct cylinder
< / BR>where
hg- the axial dimension of the cylindrical body,
a is the radius of the base of the cylindrical body.For voltage drop and current through the resistor expressions
Ie= Eoa2, (4)
where Eabout= intensity of the issled thee= UeIe= 2E2oa3x = E2oa2hgthat is identically equal to the power of the source field in the volume of the sensor, so the sensor and does not introduce distortion.In the case of a cylindrical sensor with waterway electrical connections, where the waterway is made in the form of truncated direct cones (Fig. 2), the radius of the electrode is determined in accordance with (2) from equation
< / BR>where
- half the angle at the top of the housing. In particular, when = 45ofrom (5) we get
< / BR>In this case, when the change of the environment condition (2) and all related ratios are performed automatically as you fill the canals surrounding water.When the direction of the intensity vector of the investigated electric fields are not pre-determined, the most preferred is the use of three-component sensor. Besides the already noted above advantages of the sensor (Fig. 2), can be further noted almost perfect geometric symmetry of all three channels. Because of the inertia of the added masses of water enclosed between the plates of the screens, the sensor is not sensitive to changes in temperature and pressure of the enclosing environment. P even in the presence of weak currents. It should be added and the number of operational advantages: ease of transport, ease of marine production, protection of electrodes from accidental damage. Metrological parameters of the sensor, in particular the conversion factor can be changed in accordance with the specific requirements on the measurements due to extra plates on the already prepared for the production of the sensor.The calculation of the resistance of the streaming channel is calculated by the formula
< / BR>Taking into account (7) for cubic primary Converter, you can define the basic geometrical relations of the three-PP, without introducing distortions in the studied field.As
< / BR>here we define the size of the electrode
b = a/2
and the height of the truncated regular four-sided pyramid, forming a streaming channel
< / BR>Thus, a three-component sensor (Fig. 2) will contribute in the study of homogeneous electric field minimum distortion, if the square of the electrode is less than half of fin plates of the screen.The above indicates that the sensor, differing from the known, ensures minimum distortion investigated ELEKTRIChESKIE E. C. Measurements of electric and magnetic fields in conductive media. M.: Energoatomizdat, 1985, 254 S.2. USSR author's certificate N 615440, G 01 F 3/06, 1978.3. U.S. patent N 3641427, 1972. 1. The sensor strength of the electric field, containing dielectric housing with hermetically mounted flat metal electrodes, characterized in that the casing is made in the form of a hollow straight cylinder, the electrodes located inside the housing symmetrically about the axis and the Central section of the casing and communicated with the environment through the waterway, having the form of truncated cones, and the electrodes are short-circuited through the coil of the current transformer, the ratio of the geometric dimensions selected from the condition
R = 2Rk,
where R is the resistance of the medium volume displaced by the probe;
Rkthe resistance of the volume of medium in the streaming channel.2. The sensor strength of the electric field, containing dielectric housing made in the form of a hollow cube sealed with a flat metal electrodes on the faces of the cube, and each pair of oppositely spaced electrodes electrically connected, characterized in that it is equipped Engrande pyramids, through which electrodes is in communication with the external environment, while the smaller pyramid base are supported on the electrodes, the height of the pyramids is selected equal to one third of the larger its base as the side of the larger base twice the side of the smaller base, and electrodes located on opposite faces of the cube, in pairs shorted through the coils of the transformers.
R = (0,25oC 0,3)(A + B)
A and B are respectively the width and height of the cross-section of the outer conductor of THE camera, B = (0,7oC0,1)
FIELD: laboratory tests of operation of aerials and direction finders.
SUBSTANCE: separate uniform field formers are used for both kinds (E- and H-) of waves. Electric field (E) former is disposed inside magnetic field (H) former in such a way that uniform fields formed by both formers could coincide or cross each other in bigger area to create electromagnetic (EH) uniform field at that area. Tested aerial is mounted precisely into the area. Relation between intensities of electric and magnetic field is changed by means of matching dividers mounted at output of signal oscillator. Sonic frequency generator or pulse generators are used as signal oscillator. Any component of field can be changed without making changes in the others.
EFFECT: improved noise immunity; widened range of working frequencies.
3 cl, 3 dwg