SU898351A1 - Magnetic field pickup - Google Patents

Description

(54) MAGNETIC FIELD SENSOR

one

The invention relates to a technique for measuring variable and pulsed magnetic fields, is intended to simultaneously measure at one point in space the three components of the magnetic field vector and the vector itself in the Cartesian coordinate system and can be used in the technique of strong magnetic fields, nuclear physics and geophysics.

A high-frequency electromagnetic microprobe containing three inductors is known, in which the simultaneous measurement of three mutually perpendicular components of the magnetic field vector is ensured by the fact that the coils are wound on a common substrate in three mutually perpendicular planes.

The disadvantage of this probe is the presence of strong interference in the measurement of variable and pulsed magnetic fields, due to the action of the accompanying electric field (unshielded probe coils are antennas with a certain height).

The closest technical solution to the proposed invention is a device containing two pairs of sensitive elements arranged on a sphere in pairs-orthogonally and connected in pairs to a counter 2l.

The drawback of the device lies in its low accuracy.

The purpose of the invention is to improve the measurement accuracy.

The goal is achieved by the fact that in a magnetic field sensor containing 2n identical sensing elements arranged in pairs orthogonally, one ends of the sensing elements are connected in pairs, the second ends are connected to each other at the center of symmetry of the sensor.

Claims (2)

The drawing shows a diagram of the sensor. 3898. The sensor has three pairs of sensitive elements 1-1, 1-2, 1-3, 1-4, 1-5, 1-6 in the form of flat spiral inductor coils wound counter-to-one and shunted by resistors 2-1, 2- 2, 2-3, 2-4, 2-5, 2-6 by the value where (L) is the frequency of the measured field, L is the inductance of the coil. The coils have the same number of turns, the same geometrical dimensions and are fixed on the ball 3 of insulating material symmetrically with respect to the planes of the Cartesian coordinate system. All coils are electrically connected by the same. pins directly with each other in the center of symmetry (the origin of coordinates. The potential coil pins are connected in pairs to differential measuring devices 4-1, 4-2, 4-3, and from them to the adder 5. The sensor works as follows. When acted upon or pulsed magnetic field in each pair of coils 1 in accordance with the Farah electromagnetic induction law; positive and negative voltage pulses are induced, proportional to the strength of that component of the magnetic field vector This pair of coils is axially directed. The voltage pulses from the coils are fed to the differential measuring instruments 4 and the adder b, where the useful signal is finally filtered out of common mode electrical noise and the magnetic field vector and its direction are determined. The shunting of the coils by rheistors 2 ensures independence sensitivity of the sensor from the frequency of the measured field Recorders of output pulses from the sensor are differential meters: -; devices 4 and adder 5 can be constructively compatible live with a sensor and execute as a memory device or an electro-optical converter (a transmitter with information transfer from dat- ages to an adder via optical fibers is not shown). The accompanying electric field, for example, directed along the Z axis, acts only on coils located on the same axis and having a minimum height in the direction of the floor. The remaining coils fall into the screened zone of the upper and lower coils. The conditions of mutual screening of the coils and their low effective height are also observed in any other direction of the electric field, as is easily seen by decomposing the vector E into its components. In addition, despite the separation of the coils on iieKOTOpoe distance h from the center of the sensor, if the condition is h GL, where D, is the wavelength of the measured magnetic field, the sensor gives a close fit to the point measurement, and the components of the vector H in the center of the sensor with an error of no more than 1%, equal to the sum of the values of the components of the magnetic field measured by each pair of coils on the axes X, Y, Z around the center of the sensor. An experimental test on a model constructed in the same way as a description of two inductors in a strong electromagnetic field showed that the background from an electric component with a strength of up to 100 kV / m does not exceed 8% of the useful signal. Claims of the Magnetic Field Sensor Containing 2p Identical Sensing Elements Arranged in Pairs Orgogononno, One Ends of Sensing Elements Are Coupled In Pair To Counter, Characterized In That In order To Improve Accuracy, The Second Ends Of Sensing Elements Are Connected With Each Other At The Center Of Symmetry Of Dates . Sources of information taken into account in the examination 1..The author's certificate of the USSR No. 250293, cl. G O R 29/08, 1967. 2. USSR author's certificate in application number 2530212, cl. G01 R 33/02, 1977. 1-6 h .. 1i 2-2