RU2645840C1 - Device for measuring strength of constant magnetic field based on flux-gate transmitter - Google Patents

Abstract

FIELD: measuring equipment.

SUBSTANCE: device for measuring the strength of the constant magnetic field based on a flux-gate transmitter includes a flux gate, containing an exciting winding, a square-wave generator, and a capacitor. The output of the square-wave generator is designed to transmit a signal to the exciting winding of the flux gate through the capacitor and the exciting winding is fed by voltage emissions that occur when the square-wave generator is in operation inductive load.

EFFECT: increasing the efficiency of measuring the strength of a constant magnetic field.

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Description

FIELD OF THE INVENTION

The invention relates to the field of electrical engineering and can be used in devices for measuring the parameters of a weak constant magnetic field based on a flux-gate transducer.

State of the art

A device for measuring magnetic field strength based on a flux-gate transducer (Flux-gate magnetometer RU 2103703) is known. The disadvantage of this magnetometer is the complexity of the circuit due to the additionally introduced phase shifter and pulse shaping device.

A device based on a flux-gate transducer for measuring magnetic fields (RU 2085962) is known. The disadvantage is that increasing the sensitivity of the device is due to a significant complication of the circuit and the introduction of additional elements (comparison unit, digital integrator, digital computer, analog-to-digital converter, differential amplifier, etc.), which significantly increases the cost of the device.

A device for measuring constant magnetic fields with a standard excitation winding of a flux-gate transducer described in the literature [Yu. "Flux-gate devices." - L .: Energoatomizdat. 1986. 188 p., Milovzorov V.P. “Electromagnetic automation devices. A textbook for students of the specialty "Automation and Telemechanics" of universities. " - M .: “Higher. School ", 1974. 416 p., Ripka, P. Magnetic Sensors and Magnetometers / P. Ripka. - Boston: Artech house, 2000.494 p. and etc.].

In known devices for measuring constant magnetic fields, a standard circuit for switching on a flux gate and feeding the field winding is carried out by a sinusoidal voltage or a pulsed voltage of a sawtooth or rectangular shape with a frequency of up to hundreds of kilohertz. It was found that with increasing voltage of the excitation winding (rms value or amplitude in the pulse), the sensitivity of the flux gate increases. However, an increase in voltage leads to an increase in power consumption of the measuring device.

The present invention allows to increase the sensitivity of the measuring device due to the refinement of the inclusion circuit of the flux gate and the special supply of its field winding.

Disclosure of invention

The basis of the present invention is the creation of a device for measuring the intensity of a constant magnetic field on the basis of a flux-gate transducer with increased sensitivity, low power consumption, compactness and characterized by a simple circuit and low cost. In the implementation of the present invention, it becomes possible to eliminate the constant component of the signal, reduce the power consumption of the measuring device, significantly increase the amplitude of the voltage on the field winding and, as a result, increase the sensitivity of the flux-gate without increasing the supply voltage and power consumption.

The purpose of the present invention is to increase the efficiency of measuring the intensity of a constant magnetic field.

The technical result is to increase the efficiency of the measuring device by increasing the sensitivity of the flux-gate transducer, reducing power consumption, as well as the dimensions and weight of the device.

The technical result is achieved in that a device for measuring a constant magnetic field based on a flux-gate transducer includes a flux-gate containing an excitation winding, a rectangular pulse generator and a capacitor, while the output of the rectangular-pulse generator is configured to transmit a signal to the excitation winding of the flux-gate through a capacitor, and the field winding is carried out by means of voltage surges that occur during operation of the square-wave generator on and inductive load.

Brief Description of the Drawings

In FIG. 1 shows a device for measuring the intensity of a constant magnetic field.

In FIG. Figure 2 shows the voltage graphs at the output of the generator (a) and at the excitation winding of the flux gate (b).

The implementation of the invention

The circuit of the device of increased sensitivity for measuring the intensity of a constant magnetic field contains the following components (Fig. 1):

- a flux gate with three windings: field winding L1, consisting of two counter-wound halves L1 'and L1' ', a measuring winding L2 and a compensation winding L3,

- a rectangular pulse generator, made, for example, on the elements AND-NOT, with the ability to control the frequency within 1-200 kHz.

- connecting capacitor C1, transmitting a signal from the output of the generator to the excitation winding of the flux gate, which is a fundamental feature of the circuit.

- a recording device connected to the output of the measuring winding, with any measuring device — a voltmeter or ammeter — and with the corresponding switching circuit. The measuring device must be pre-calibrated in units of tension;

- a compensator to set the value of the recording device to zero using a variable resistor R2 in the absence of a measured magnetic field strength.

When the square-wave generator is used for the inductive load, which is the excitation coil of the flux gate, voltage surges occur at the positive and negative edges of the pulses (Fig. 2, a). The duration of the emissions is short and amounts to units of microseconds, and their value can significantly exceed the voltage in the pulse.

The capacitance of the connecting capacitor is selected in such a way as to ensure the maximum amplitude of voltage spikes on the excitation winding of the flux gate. The capacitance in this case, as a rule, does not exceed 0.01 μF.

Thus, a fundamental feature of the proposed solution is the use of voltage surges to power the excitation winding of a flux gate (Fig. 2, b). Such a power supply can significantly increase the voltage on the field winding and, as a result, increase the sensitivity of the flux gate without increasing the supply voltage. The measuring device constructed in this way is characterized by simplicity, low energy consumption and does not require complex and expensive elements.

The high sensitivity of the device allows measurements to be made at a sufficient distance from the source of a constant magnetic field and eliminates the need to incorporate a flux gate into a structure containing the source.

Preparation of the device for operation consists in taring the scale of the measuring device in units of magnetic field strength.

This device has been tested on a prototype. The test results indicate the achievement of the task.

Claims (7)

A device for measuring the intensity of a constant magnetic field based on a flux-gate transducer, including a flux-gate, containing an excitation winding, a rectangular pulse generator and a capacitor, characterized in that - the flux gate contains an excitation winding L1, consisting of two counter-wound halves L1 'and L1' ', a measuring winding L2 and a compensation winding L3, - a square-wave generator is made on AND-NOT elements with the ability to control the frequency within 1-200 kHz, - the capacitance of the capacitor C1 does not exceed 0.01 μF, - contains a recording device connected to the output of the measuring winding, - contains a compensator for setting the recording instrument to zero using a variable resistor R2 in the absence of a measured magnetic field strength, while the output of the rectangular pulse generator is configured to transmit a signal to the excitation winding of the flux gate through the capacitor, and the excitation winding is energized by voltage surges that occur during operation of the rectangular pulse generator to the inductive load.

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