Search

CN-121986267-A - Fluxgate current sensor

CN121986267ACN 121986267 ACN121986267 ACN 121986267ACN-121986267-A

Abstract

Fluxgate current sensor (1) comprising a fluxgate head (2) and a main magnetic conductor assembly (5), the fluxgate head comprising a soft magnetic core (14) and an excitation coil (16) wound around the soft magnetic core, the soft magnetic core surrounding a central channel (20, 20 a). The fluxgate sensor further comprises a planar substrate extending through the central channel between a first (10) and a second (11) connecting edge, the main conductor assembly comprising a plurality of stacked main conductor layers formed on or inside the planar substrate, each main conductor layer being separated from an adjacent main conductor layer by an insulating layer.

Inventors

  • S. Trumbert

Assignees

  • 莱姆国际股份有限公司

Dates

Publication Date
20260505
Application Date
20241001
Priority Date
20231025

Claims (10)

  1. 1. Fluxgate current sensor (1) comprising a fluxgate head (2) comprising a soft magnetic core (14) surrounding a central channel (20, 20 a) in the form of an elongated slot and a main conductor assembly (5) extending through the central channel between a first connection edge (10) and a second connection edge (11), each main conductor layer being separated from an adjacent main conductor layer by an insulating layer, and an excitation coil (16) wound around the soft magnetic core.
  2. 2. The fluxgate current sensor according to claim 1, wherein the main conductor assembly comprises a first connection terminal (7) provided along the first connection edge (10) of the substrate, which is located outside the central channel (20) of one side of the fluxgate head (2), and a second connection terminal (8) provided along the second connection edge (11) of the substrate, which is formed outside the central channel of the second side of the fluxgate head in the axial direction.
  3. 3. A fluxgate current sensor according to any of the preceding claims, wherein the substrate takes the form of a circuit board (4), the main conductor layers being formed on different layers within the circuit board.
  4. 4. Fluxgate current sensor according to any of the preceding claims, wherein the first connection end terminal (7) comprises conductive pads arranged along and spaced apart from adjacent connection terminals, the conductive pads being provided for surface mount soldered connection with conductive tracks of an external circuit board (101).
  5. 5. Fluxgate current sensor according to any of the preceding claims, wherein the soft magnetic core (14) of the fluxgate head is mounted in a core receiving cavity (19) of a coil support housing (18), the excitation coil (16) being wound around the coil support housing (18).
  6. 6. Fluxgate current sensor according to any of the preceding claims, wherein the fluxgate head is mounted inside a housing (3), the housing (3) being provided with a central channel (20 a), the central channel (20 a) being intended to be inserted into the substrate forming the main conductor assembly.
  7. 7. Fluxgate current sensor according to any of the preceding claims, wherein each of the main conductor layers of the main conductor assembly (5) comprises a central portion (9) connecting the first and second connection terminals, wherein the central portions of a plurality of stacked main conductor layers completely overlap each other.
  8. 8. A fluxgate current sensor according to any one of the preceding claims, wherein each of the main conductor layers includes a slot (22) extending from a side edge that extends axially of the central channel.
  9. 9. The fluxgate current sensor according to any one of the preceding claims, wherein the first and second connection terminals of each main conductor layer are arranged diametrically opposite with respect to a center line extending axially along the central channel as a symmetry axis.
  10. 10. An electronic system (100) comprising a fluxgate current sensor according to any of the preceding claims and a system circuit board (101) with electrically conductive tracks (102), the system circuit board further comprising a fluxgate head receiving cutout (103), a portion of the fluxgate head (2) being inserted into the fluxgate head receiving cutout (103).

Description

Fluxgate current sensor The present invention relates to a fluxgate current sensor, in particular for mounting on a circuit board. It is known to provide a fluxgate sensor arranged to be mounted on an electronic circuit board, the fluxgate sensor being adapted to measure leakage current in a single-phase or multi-phase main conductor assembly passing through its central channel. Unless a residual current is generated due to leakage or short-circuiting of at least one phase current, the magnetic fields generated by the main conductors should cancel each other. Fluxgate sensors are known which comprise a soft magnetic core surrounded by an excitation coil, the core being configured to be alternately saturated when an alternating excitation current is passed through the excitation coil. The external magnetic field affects this alternating saturation phenomenon and thus the excitation behaviour, by measuring which the magnitude of the external magnetic field can be determined. For the residual current sensor, when at least one phase is leaked, the magnetic field generated by the main magnetic component is not zero, and the magnitude of the magnetic field corresponds to the magnitude of the leakage current. In some conventional fluxgate sensors 1', as shown in fig. 4, the main conductor 5' is in the form of a wire that passes through the circular channel 20' of the annular sensor. The toroidal core has a height and the main conductor is soldered to the pins of the circuit board 101', plus the height of the toroidal core, resulting in the assembly being taller than the other electronic components. In view of the space usage requirements of various electronics, it is necessary to reduce the height of the electronic components on the circuit board. In addition, the wire diameter and location of the main conductor assembly can result in different spacing between each main conductor and the fluxgate sensor, which can result in the generated magnetic field not being completely cancelled. One of the problems with the distribution of the electric field of the conductors of the wires is the need to provide an electrical shield between the fluxgate sensor and the main conductor to attenuate the dipole field effect created by each wire, and such a shield structure also creates additional costs. The production cost of the traditional residual current sensor is higher as that of the circuit board assembly, manual intervention is needed in the assembly process, and small deviation often exists between the pin connection part of the main conductor assembly and the positioning of the corresponding wiring hole on the circuit board, so that the assembly difficulty is high. In view of the foregoing, it is an object of the present invention to provide a fluxgate current sensor that is compact, highly accurate, and inexpensive to manufacture and install. It would be advantageous to provide a low height fluxgate sensor that is mountable on an external electronic system circuit board. It would be advantageous to provide a fluxgate sensor for residual current measurement that is mountable on a circuit board of an electronic system and capable of automated assembly using conventional electronic component assembly equipment. It would be advantageous to provide a fluxgate sensor for residual current measurement that is structurally robust, reliable and accurate. It would be advantageous to provide a fluxgate current sensor that is lightweight. In some applications it is advantageous to provide a fluxgate current sensor that can be easily mounted and connected to an external electronic system circuit board. In some applications it is advantageous to provide a fluxgate current sensor that is particularly suited for residual current measurement. In some applications it is advantageous to provide a fluxgate current sensor that is particularly suited for residual current measurement of multi-phase conductor devices. The object of the invention has been achieved by providing a system according to claim 1. The dependent claims set forth advantageous technical features of the various embodiments of the invention. A fluxgate current sensor includes a fluxgate head and a main magnetic body assembly, the fluxgate head including a soft magnetic core surrounding a central passage in the form of an elongated slot and an excitation coil wound around the soft magnetic core. The fluxgate sensor further includes a planar substrate extending through the central channel between the first and second connection edges, the primary conductor assembly including a plurality of stacked primary conductor layers formed on or within the planar substrate, each primary conductor layer being separated from an adjacent primary conductor layer by an insulating layer. In a preferred embodiment, the main conductor assembly includes a first connection terminal provided along the first connection edge of the substrate, which is located outside the central passage on one side o