RU1805369C - Method and device for induction measuring of electric conductivity of liquid - Google Patents

Abstract

Scope: hydrological and oceanographic studies. SUMMARY OF THE INVENTION: the method is; that in a non-contact three-transformer conductivity meter, two magnetic fluxes are excited - a low frequency F and a high frequency f, an order of magnitude or more higher than the frequency F. In the second current transformer (T), a second magnetic flux of frequency f is excited, which is equal in magnitude and opposite direction the first magnetic frequency flux, the amplitudes of these magnetic fluxes being selected in the saturation region of the magnetic cores, and the electrical conductivity is determined by the magnitude of the voltage of the second harmonic of frequency f. The device consists of three T, made on a toroidal magnetic circuit and covered by a common coil. A frequency alternating voltage generator F is connected to the voltage winding T. A frequency voltage generator f is connected to two identical series windings of the first and second T currents. The measuring winding is shunted by a capacitor. 2 sec And 1 s.p. f-ly, 1 ill. (L C

Description

The invention relates to measuring technique and can be used in hydrological and oceanographic studies.

The purpose of the invention is to increase sensitivity and reduce the volume of spatial averaging.

The drawing shows a block diagram of a device that implements the method of induction measurement of electrical conductivity.

The method is implemented in the following sequence.

In a non-conductive conductivity meter consisting of a voltage transformer (t-pa) and two identical t-currents, a low-frequency voltage magnetic flux F and two high-frequency voltage magnetic flux f of equal magnitude are excited; but counter directional. The amplitudes of these magnetic fluxes are selected in the saturation region of the magnetic cores. The signal is taken from the measuring winding and the second harmonic of the frequency f is extracted, and then along the calibration

with Oh

ate about

dependencies determine the value of electrical conductivity.

A device for measuring the electrical conductivity of a liquid that implements the method comprises a non-contact measuring gamma generator (PI) 1, a low frequency generator 2 F, a high frequency generator 3. measuring amplifier (IU) 4, voltage transformer 5, voltage transformer 6. Voltage transformer 5 is made on a magnetized magnetic conductor 7, current transformer is two-section, is made on two toroidal cores 8 and 9. The UT-pa voltage voltage 5 is connected to the generator 2. The windings 11 and 12 tons of current are identical and are located respectively on the magnetic circuits 8 and 9.

The windings are connected in opposite and in series, with the free ends of the windings 11 and 12 connected to the generator 3. The measuring winding 13 covers the magnetic circuits 8 and 9 and is connected to the DUT 4. In parallel to the winding 13, a capacitor 14 is connected.

Structurally, voltage transformer 7 is coaxial with current transformer 6 and inside magnetic circuits 8 and 9.

The device operates as follows.

IP 1 is placed in the test fluid. The magnetic circuits of T-5 and T-6 are covered by a single fluid communication loop. The capacitor 14 sets: the measuring circuit (capacitor 14, winding 13) at a frequency of 2f, where f is the frequency of the generator 3. After turning on the generator 3, the windings 11 and 12 are excited in the magnetic circuits 8 and two different and counter-directed magnetic fluxes, and the amplitude of the generator 3 is set such that a maximum envelope value is provided. Then, at the input of the DUT 4, the high-frequency voltage turns out to be modulated by the frequency F, and the depth of modulation depends on the conductivity of the fluid communication loop. The amplitude of the second harmonic of frequency f is graduated in the electrical conductivity of the liquid.

Claims (3)

1. The method of induction measurement of electrical conductivity of a liquid, which consists in the fact that in a non-contact conductivity meter in the first current transformer, two magnetic fluxes are excited by a low frequency voltage F and voltage of a high frequency f, an order of magnitude or more higher than frequency F, and measure the voltage on the measuring winding, characterized in that, in order to improve the accuracy of measuring electrical conductivity, in the second current transformer of the non-contact meter, a magnetic flux of frequency f equal to the amplitude and opposite to the first magnetic flux of frequency f, the amplitudes of these magnetic fluxes being selected in the saturation region of the magnetic cores, and the electrical conductivity is determined by the magnitude of the voltage of the second harmonic Eye of frequency f. 2. Device for the induction measurement of electrical conductivity of a liquid, comprising a primary measuring transducer consisting of a voltage transformer and two current transformers made on toroidal magnetic circuits arranged coaxially and covered by a common liquid coil, a low-frequency alternating voltage generator connected to the voltage transformer winding a measuring amplifier, the input of which is connected to a measuring winding, characterized in that, in order to increase the sensitivity, a second high-frequency alternating voltage generator was introduced, the magnetic cores of the current transformers are identical, their primary windings have the same number of turns and are connected in series, and the measuring-winding covers the magnetic circuits of both current transformers and a capacitor is connected in parallel with it, and the free terminals of the primary windings of the current transformers are connected to the second generator. 3. The device according to claim 2, characterized in that, in order to reduce the volume of spatial averaging, the voltage transformer is located coaxially with the current transformers and inside them.