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KR-20260065933-A - Sensor device

KR20260065933AKR 20260065933 AKR20260065933 AKR 20260065933AKR-20260065933-A

Abstract

The sensor device (1) comprises a magnetic core part (2) capable of forming a closed magnetic path including two outer parts, two coil parts (L1, L2) configured such that windings are wound around each of the two outer parts and each generate a signal magnetic flux according to an applied AC signal, a magnetic flux generating part that generates a bias magnetic flux to circulate the closed magnetic path, an AC signal circuit (3) that applies an AC signal to the two coil parts so that a signal magnetic flux in the same direction as the bias magnetic flux is generated in each outer part, and signal output terminals (V1, V2) that output a detection signal capable of detecting a voltage balance between the two coil parts (L1, L2) that changes according to an external magnetic field acting on the magnetic core part (2).

Inventors

  • 미야자키 히로유키
  • 하타케야마 다케시

Assignees

  • 스미다 코포레이션 가부시키가이샤

Dates

Publication Date
20260511
Application Date
20241004
Priority Date
20231124

Claims (12)

  1. A first magnetic core part comprising two outer legs and capable of forming a first closed magnetic path, and Two coil sections, each configured with a winding wound around the two outer sections above and each generating a signal magnetic flux according to an applied AC signal, and A magnetic flux generating unit that generates a bias magnetic flux to circulate the first closed magnetic path, and An AC signal circuit that applies an AC signal to the two coil sections such that the signal flux in the same direction as the bias flux is generated in each of the outer sections, and A signal output terminal that outputs a detection signal capable of detecting the voltage balance between the two coil sections that changes according to the external magnetic field acting on the first magnetic core section. Sensor device equipped with
  2. The magnetic flux generating unit generates the bias magnetic flux having a magnetic field strength such that the range of permeability corresponding to a specific range within a region where the permeability linearly decays with respect to the increase in magnetic field strength in the core characteristics of the magnetic core part in which the two coil parts are installed is 40% or more and 60% or less. The sensor device described in claim 1.
  3. The signal magnetic flux generated from the two coil sections has a polarity that circulates the first closed path in the same direction, and The above AC signal circuit includes the above magnetic flux generating unit, and The above AC signal circuit applies the AC signal, in which a DC bias current corresponding to the bias magnetic flux is superimposed, to the two coil sections. The sensor device described in claim 2.
  4. The signal magnetic flux generated from the two coil sections has a polarity that circulates the first closed path in the same direction, and The above magnetic flux generating unit is, Two bias coil sections configured by winding wires around each of the two outer sections mentioned above, and A DC signal circuit that applies a DC signal to the two bias coil sections so that the bias magnetic flux is generated by the polarity circulating the first closed path in the same direction. including, The sensor device described in claim 2.
  5. The signal magnetic flux generated from the two coil sections has a polarity that circulates the first closed path in the same direction, and The above magnetic flux generating unit includes a bias magnet part locally installed in the first magnetic core part so as to generate the bias magnetic flux by means of a polarity that circulates the first closed magnetic path in the same direction. The sensor device described in claim 2.
  6. A second magnetic core part capable of forming a second closed path including one of the two outer parts and the other outer part, and A third magnetic core part capable of forming a third closed path including the other side of the two outer parts and another outer part. Equip more, The magnetic flux generating unit includes two or more bias magnets locally installed in the first magnetic core portion to generate the bias magnetic flux by means of polarity that circulates the first closed magnetic path in the same direction. The signal flux generated from one of the two coil sections has a polarity that circulates through the second closed path, and The signal flux generated from the other side of the two coil sections has a polarity that circulates through the third closed path, and The second magnetic core part and the third magnetic core part are connected through the two or more bias magnet parts, and The above-mentioned first closed section is formed by the above-mentioned two or more bias magnet sections, a part of the above-mentioned second magnetic core section, and a part of the above-mentioned third magnetic core section, A sensor device as described in claim 1 or 2.
  7. The two coil sections mentioned above are installed to be close to or in contact with a conductor through which the current to be detected flows, and A method for measuring the current value of the detected current by the above detection signal, A sensor device described in any one of claims 1 to 6.
  8. In the above AC signal circuit, the two coil sections are connected in series, and The above signal output terminal is capable of outputting an intermediate signal level of the two coil sections as the detection signal. A sensor device described in any one of claims 1 to 7.
  9. The above AC signal circuit includes a self-excited oscillation circuit having a resonant capacitor connected in parallel to the two coil sections, and applies an oscillation signal output from the self-excited oscillation circuit to both ends of the two coil sections. The sensor device described in claim 8.
  10. A magnetic core for current detection, having an air gap, is further provided in a magnetic path formed by the flow of a detected current, said air gap being inserted therein. The signal flux generated from the two coil sections has a polarity that circulates the first closed path in the same direction, and The first magnetic core portion further includes a middle leg portion, and the two outer leg portions and the middle leg portion are arranged in the air gap in a direction extending orthogonally to each core end face facing each other with the air gap in between in the magnetic core for current detection. The area of the cross-section perpendicular to the extension direction in the middle section of the first magnetic core part is equal to or greater than the area of the core end surface of the magnetic core for current detection. The first magnetic core portion is aligned such that, when viewed from a direction orthogonal to the core end surface, the cross-section of the intermediate portion encloses the core end surface of the magnetic core for current detection. A sensor device described in any one of claims 1 through 5, 8 and 9.
  11. The core end surface of the magnetic core for current detection and the first magnetic core portion are joined together. The sensor device described in claim 10.
  12. A gap is formed between the core end surface of the magnetic core for current detection and the first magnetic core portion, The sensor device described in claim 10.

Description

Sensor device The present invention relates to a sensor device based on magnetic detection. A Hall element is known to perform magnetic detection using the Hall effect as a magnetic sensor. Patent documents 1 and 2 below disclose a current sensor in which a Hall element is placed in the gap of a magnetic core. Patent document 1 below addresses the problem that detection errors occur due to changes in the characteristics of the magnetic core and the Hall element with temperature changes, and to solve this, a temperature compensation circuit is added to the amplification circuit of the output signal of the Hall element. Furthermore, in patent document 2 below, in order to reduce errors caused by the placement precision of the Hall element during sensor assembly, the Hall element is used to detect the direction of the current to be detected, and is not used directly to measure the magnitude of the current to be detected. [Fig. 1] This is a schematic diagram showing the configuration of a sensor device according to the first embodiment. [Fig. 2] This is a schematic diagram showing the flow of magnetic flux within the magnetic core. [Fig. 3] This is a schematic diagram showing the configuration of a sensor device according to the second embodiment. [Fig. 4] This is a schematic diagram showing the configuration of a sensor device according to the third embodiment. [Fig. 5] This is a graph showing the core characteristics (permeability and magnetic field strength characteristics) of a magnetic core. [Fig. 6] This is a schematic diagram showing the configuration of a sensor device according to the fourth embodiment. [Fig. 7] This is a circuit diagram showing a first example of an AC signal circuit and a signal output circuit. [Fig. 8] This is a diagram showing an example of an output signal when the AC signal circuit and signal output circuit shown in Fig. 7 are applied. [Fig. 9] This is a circuit diagram showing a second example of an AC signal circuit and a signal output circuit. [Fig. 10] This is a diagram showing an example of an output signal when the AC signal circuit and signal output circuit shown in Fig. 9 are applied. [Fig. 11] This is a schematic diagram showing the external appearance of a current sensor device according to the fifth embodiment. [Fig. 12] This is a partial schematic diagram showing the arrangement of the magnetic core portion of the sensor device in the current sensor device according to the fifth embodiment. [Fig. 13] This is a graph showing an example of a voltage signal (detection signal) output from a signal output terminal in a current sensor device according to the fifth embodiment. [Fig. 14] This is a schematic diagram showing an example of the arrangement of the current line of the current sensor device according to the 6th embodiment. [Fig. 15] This is a schematic diagram showing the external appearance of a sensor device according to the seventh embodiment. [Fig. 16] This is a schematic diagram showing the flow of signal flux and bias flux in a sensor device according to the seventh embodiment. [Fig. 17] This is a schematic diagram showing the external appearance of a sensor device according to a modified example of the seventh embodiment. [Fig. 18] This is a schematic diagram showing an example of the arrangement of the current line of the current sensor device according to the eighth embodiment. [Fig. 19] This is a graph showing the results of the evaluation test of the current sensor device in this embodiment. Embodiments of the present invention will be described below. Each of the embodiments described below is an example, and the present invention is not limited to the configurations of each of the following embodiments. [First Embodiment] FIG. 1 is a schematic diagram showing the configuration of a sensor device (1) according to a first embodiment. The sensor device (1) according to a first embodiment is equipped with a magnetic core part (2), a coil part (L1) and a coil part (L2), an AC signal circuit (3), a signal output terminal (V1) and a signal output terminal (V2), etc. In the example of FIG. 1, the magnetic core part (2) is formed by combining an E-type core (21) and an E-type core (22), each having a middle section and two outer sections, to form a closed magnetic path, and has a core shape called an EE-type core. The E-type core (21) has an outer section (21a), an outer section (21b), and a middle section (21c), and the E-type core (22) has an outer section (22a), an outer section (22b), and a middle section (22c). The middle section (21c) and the middle section (22c) may be cylindrical in shape or prismatic in shape. The magnetic core part (2) corresponds to the first magnetic core part. There are cases where the outer section (21a) and outer section (22a) connected as one, and the outer section (2lb) and outer section (22b) connected as one are each referred to as the core outer section, and the middle section (21c) and middle section (22c) connected as one a