[go: up one dir, main page]

WO2013179613A1 - Capteur de courant - Google Patents

Capteur de courant Download PDF

Info

Publication number
WO2013179613A1
WO2013179613A1 PCT/JP2013/003276 JP2013003276W WO2013179613A1 WO 2013179613 A1 WO2013179613 A1 WO 2013179613A1 JP 2013003276 W JP2013003276 W JP 2013003276W WO 2013179613 A1 WO2013179613 A1 WO 2013179613A1
Authority
WO
WIPO (PCT)
Prior art keywords
current
magnetic
magnetic field
magnetoresistive element
current path
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/JP2013/003276
Other languages
English (en)
Japanese (ja)
Inventor
正憲 鮫島
澄夫 前川
隆司 梅田
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Corp
Original Assignee
Panasonic Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Panasonic Corp filed Critical Panasonic Corp
Publication of WO2013179613A1 publication Critical patent/WO2013179613A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
    • G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
    • G01R15/20—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using galvano-magnetic devices, e.g. Hall-effect devices, i.e. measuring a magnetic field via the interaction between a current and a magnetic field, e.g. magneto resistive or Hall effect devices
    • G01R15/205—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using galvano-magnetic devices, e.g. Hall-effect devices, i.e. measuring a magnetic field via the interaction between a current and a magnetic field, e.g. magneto resistive or Hall effect devices using magneto-resistance devices, e.g. field plates

Definitions

  • the present invention relates to a current sensor that measures a current to be measured by detecting a magnetic field generated around a current line through which the current to be measured flows.
  • FIG. 7 is a schematic plan view of a conventional current sensor.
  • the current sensor 1 includes a substrate 2 placed parallel to the XY plane.
  • the substrate 2 is formed with slits 3 penetrating from the front surface 2a of the substrate 2 to the back surface 2b.
  • a plate-like current path 4 through which the measured current Id flows is inserted into the slit 3.
  • the direction of the measured current Id flowing through the current path 4 is the negative direction of the Z-axis, that is, the direction penetrating perpendicularly from the front surface to the back surface.
  • Magnetoresistive elements 5 a and 6 a are attached to the surface 2 a of the substrate 2.
  • the magnetoresistive elements 5 a and 6 a are provided at symmetrical positions with respect to the current path 4.
  • a bias magnet 5b for applying a bias magnetic field to the magnetoresistive element 5a and a bias magnet 66b for applying a bias magnetic field to the magnetoresistive element 6a are attached.
  • the magnetoresistive element 5a is disposed directly above the bias magnet 5b with the substrate 2 interposed therebetween, and the magnetoresistive element 6a is disposed directly above the bias magnet 66b with the substrate 2 interposed therebetween.
  • each bias magnet 5b, 66b The area of the cross section of each bias magnet 5b, 66b is made larger than the area of the cross section of the magnetoresistive elements 5a, 6a arranged immediately above. Further, the bias magnets 5b and 66b are arranged with the N poles facing each other.
  • the magnetoresistive elements 5a and 6a are provided with magnetoresistors Ra and Rb constituting a half bridge circuit, respectively.
  • Each magnetic resistance Ra, Rb is formed on the same surface 2 a of the substrate 2.
  • the easy magnetization axes (current flow directions) of the respective magnetic resistances Ra and Rb are the same as the extending direction of each magnetic resistance, and the respective easy magnetization axes are parallel to the surface 2 a of the substrate 2.
  • each of the magnetic resistances Ra and Rb is arranged such that the easy axis of magnetization and the direction of the induced magnetic field generated by the current Id to be measured form 45 °.
  • the magnetic resistance Ra and the magnetic resistance Rb in the magnetoresistive element 5a are connected at a connection point 7a, one end of the magnetic resistance Ra is connected to the ground, and one end of the magnetic resistance Rb is connected to the power source Vcc. Further, in the magnetoresistive element 6a, the magnetic resistance Ra and the magnetic resistance Rb are connected at a connection point 7b, one end of the magnetic resistance Ra is connected to the ground, and one end of the magnetic resistance Rb is connected to the power source Vcc.
  • the connection points 7a and 7b are connected to the input terminals of the differential amplifier.
  • FIGS. 8A and 8B are explanatory diagrams of magnetic flux density vectors acting on the current sensor 1.
  • the magnetoresistive elements 5a and the magnetic flux density vector Bm 1 from the bias magnet 5b is applied to the positive direction of the Y-axis
  • the magnetic flux density vector Bm 2 from the bias magnet 66b is the magnetoresistive element 6a is Y Applied in the negative direction of the shaft.
  • the resistance values of the magnetic resistances Ra and Rb are uniformly reduced by the action of the magnetic flux density vectors Bm 1 and Bm 2 .
  • the full bridge circuit composed of the magnetoresistive elements 5a and 6a is balanced, so that the output VOUT of the differential amplifier remains at a so-called zero point potential of Vcc / 2, for example.
  • the magnetic flux density vector Bc 1 facing the positive direction of the X-axis is further applied to the magneto-resistive element 5a.
  • synthetic magnetic flux density vector B 1 obtained by combining the magnetic flux density vector Bc 1 by the measured current Id is applied.
  • the resultant magnetic flux density vector B 1 forms an angle ⁇ with the magnetic flux density vector Bm 1 .
  • the magnetoresistive element 6a is the magnetic flux density vector Bc 2 is further applied in the negative direction of the X axis.
  • the synthetic magnetic flux density vector B 2 obtained by combining the magnetic flux density vector Bm 2, Bc 2 is applied to the magnetoresistive element 6a.
  • the resultant magnetic flux density vector B 2 forms an angle ⁇ with the magnetic flux density vector Bm 2 .
  • the magnitude of the magnetic flux density vector Bm 1 is substantially uniform within the magnetoresistive element 5 a, but the magnitude of the magnetic flux density vectors Bc 1 and Bc 2 becomes substantially inversely proportional to the distance from the current path 4. .
  • the magnetoresistive elements 5a and 6a have the same magnetic flux density vectors Bm 1 and Bm 2 , and the magnetic flux density vectors Bc 1 and Bc 2 at positions symmetrical with respect to the current path 4 in the magnetoresistive elements 5a and 6a. Are configured to have the same size. For this reason, the resultant magnetic flux density vectors B 1 and B 2 at symmetrical positions with respect to the current path 4 in the magnetoresistive elements 5a and 6a, for example, the centers of the magnetoresistive elements 5a and 6a, have the same magnitude and the direction of 180 degrees. Since they are different, the sum of both composite magnetic flux density vectors B 1 and B 2 is zero.
  • the magnetic flux density vectors Bc 1 and Bc 2 decrease, so that the phase ⁇ decreases and the combined magnetic flux density vectors B 1 and B 2 decrease.
  • the output V OUT of the differential amplifier becomes V 2 (V 2 ⁇ V 1 ), for example, which is larger than the zero point potential of Vcc / 2. In this way, the measured current Id flowing in the current path 4 from the output V OUT of the differential amplifier can be detected.
  • the resistance value of the magnetic resistance Ra of the magnetoresistive element 5a increases and the resistance value of the magnetic resistance Rb decreases.
  • the potential at the connection point 7a increases.
  • the resistance value of the magnetoresistor Ra of the magnetoresistive element 6a increases and the resistance value of the magnetoresistor Rb decreases.
  • the potential at the connection point 7b increases.
  • the full bridge circuit composed of the magnetoresistive elements 5a and 6a maintains a balanced state, so that the output VOUT of the differential amplifier remains at a so-called zero point potential of Vcc / 2, for example.
  • the current sensor 1 detects the measured current Id flowing through the current path 4 in a non-contact manner without causing an error in the current value of the measured current Id even when an external magnetic field is present. be able to.
  • Patent Document 1 A conventional current sensor similar to the current sensor 1 is described in Patent Document 1, for example.
  • the current sensor includes a current path configured to flow a current to be measured, first and second magnetoresistive elements arranged around the current path, and a first direction in a direction coinciding with a direction in which the current to be measured flows. And a first magnetic field generator for applying a second bias magnetic field to the first and second magnetoresistive elements, respectively.
  • the current to be measured is detected from the output signals of the first and second magnetoresistive elements.
  • the first and second magnetoresistive elements respectively have first and second magnetoresistors arranged along first and second planes parallel to the current path. The distance between the first plane and the current path is equal to the distance between the second plane and the current path.
  • This current sensor is small and can accurately measure the current flowing in the current path.
  • FIG. 1A is a side view of a current sensor according to an embodiment of the present invention.
  • 1B is a cross-sectional view of the current sensor shown in FIG. 1A along line 1B-1B.
  • FIG. 2 is a plan view of the magnetoresistive element of the current sensor in the embodiment.
  • FIG. 3A is a side view of the current sensor of the example in the embodiment.
  • 3B is a cross-sectional view of the current sensor shown in FIG. 3A along line 3B-3B.
  • 4A is a bottom view of the magnetoresistive element of the current sensor shown in FIGS. 3A and 3B.
  • 4B is a cross-sectional view taken along line 4B-4B of the magnetoresistive element of the current sensor shown in FIG. 4A.
  • FIG. 4C is a top view of the magnetoresistive element of the current sensor shown in FIGS. 3A and 3B.
  • FIG. 4D is a cross-sectional view taken along line 4D-4D of the magnetoresistive element of the current sensor shown in FIG. 4C.
  • FIG. 4E is a circuit diagram of the current sensor shown in FIG. 3A.
  • FIG. 5A is a diagram showing an output change rate of the adder of the current sensor in the embodiment.
  • FIG. 5B is a diagram illustrating an output change rate of the adder of the current sensor according to the embodiment.
  • FIG. 6A is a plan view of another magnetoresistive element of the current sensor in the embodiment. 6B is a cross-sectional view of the magnetoresistive element shown in FIG. 6A along line 6B-6B.
  • FIG. 6C is a plan view of another magnetoresistive element of the current sensor in the embodiment.
  • 6D is a cross-sectional view of the magnetoresistive element shown in FIG. 6C taken along line 6D-6D.
  • FIG. 6E is a side view of a current sensor according to another example of the embodiment.
  • FIG. 7 is a schematic plan view of a conventional current sensor.
  • FIG. 8A is an explanatory diagram of a magnetic flux density vector acting on a conventional current sensor.
  • FIG. 8B is an explanatory diagram of a magnetic flux density vector acting on a conventional current sensor.
  • FIG. 1A is a side view of current sensor 21 in the embodiment of the present invention.
  • 1B is a cross-sectional view of current sensor 21 shown in FIG. 1A taken along line 1B-1B.
  • XYZ coordinates defined by the X axis, the Y axis, and the Z axis orthogonal to each other are defined as shown in FIGS. 1A and 1B.
  • the current path 22 extends in the Z-axis direction and is made of a good conductor such as copper.
  • a current Id to be measured flows through the current path 22 in the negative direction of the Z axis.
  • a magnetoresistive element 23 is disposed above the current path 22, that is, in the positive direction of the Y axis from the current path 22.
  • a magnetic field generator 24 for applying a bias magnetic field to the magnetoresistive element 23 is disposed immediately above the magnetoresistive element 23.
  • a magnetoresistive element 25 is disposed below the current path 22, that is, in the negative direction of the Y axis from the current path 22.
  • a magnetic field generator 26 that applies a bias magnetic field to the magnetoresistive element 25 is disposed immediately below the magnetoresistive element 25.
  • the magnetic field generators 24 and 26 are magnets.
  • the direction from the center of the N pole 24N to the center of the S pole 24S of the magnetic field generator 24 coincides with the flowing direction of the current Id to be measured, and from the center of the S pole 26S of the magnetic field generator 26 to the center of the N pole 26N.
  • the magnetic field generators 24 and 26 are arranged so that the direction coincides with the direction in which the measured current Id flows. That is, the magnetic field generator 24 applies a bias magnetic field in a direction coinciding with the flowing direction of the current Id to be measured to the magnetoresistive element 23, and the magnetic field generator 26 is opposite to the direction of the bias magnetic field applied to the magnetoresistive element 23.
  • a direction bias magnetic field is applied to the magnetoresistive element 25.
  • a magnetic field 27 is generated around the current path 22 by the measured current Id flowing through the current path 22.
  • a magnetic field 28 from the N pole 24N to the S pole 24S is generated around the magnetic field generator 24, and a magnetic field 29 from the N pole 26N to the S pole 26S is generated around the magnetic field generator 26.
  • FIG. 2 is a plan view of the magnetoresistive elements 23, 25, specifically a bottom view of the magnetoresistive element 23 and a top view of the magnetoresistive element 25.
  • the magnetoresistive element 23 includes an insulating substrate 131 made of an insulating member such as ceramic, and magnetic resistors 130a, 130b, 130c, and 130d that constitute a full bridge circuit.
  • the magnetoresistive element 25 includes an insulating substrate 231 made of an insulating member such as ceramic, and magnetic resistors 230a, 230b, 230c, and 230d that constitute a full bridge circuit.
  • the magnetic resistors 130a, 130b, 130c, and 130d are formed on the lower surface 131b of the insulating substrate 131, that is, the same surface of the insulating substrate 131.
  • the magnetic resistances 230a, 230b, 230c, and 230d are formed on the upper surface 231a of the insulating substrate 231, that is, the same surface of the insulating substrate 231.
  • the magnetic resistors 130a to 130d and 230a to 230d are magnetoresistive thin films made of a ferromagnetic material such as Ni—Co and having a thickness of about 0.1 ⁇ m.
  • the magnetic resistances 130a to 130d and 230a to 230d are elongated in the longitudinal direction perpendicular to the magnetic sensing direction, and sense a magnetic field in the magnetic sensing direction.
  • the longitudinal directions of the magnetic resistors 130a and 130b are perpendicular to each other, and are arranged so as to form 45 ° with the Z axis, which is the direction of the current Id to be measured.
  • the longitudinal directions of the magnetic resistors 130c and 130d are perpendicular to each other, and are arranged to form 45 ° with the Z axis.
  • each of the magnetic resistances 130 a and 130 b in the magnetoresistive element 23 is connected at a connection point 32, and one end of each of the magnetic resistances 130 c and 130 d is connected at a connection point 33.
  • the other ends of the magnetic resistors 130a and 130d are connected to the power supply Vcc, and the other ends of the magnetic resistors 130b and 130c are connected to the ground.
  • the magnetic resistances 130a and 130b are connected in series with each other, and the magnetic resistances 130d and 130c are connected in series with each other.
  • the longitudinal directions of the magnetic resistors 230a and 230b are perpendicular to each other, and are arranged to form 45 ° with the Z axis.
  • the longitudinal directions of the magnetic resistors 230c and 230d are perpendicular to each other, and are arranged to form 45 ° with the Z axis.
  • One end of each of the magnetic resistances 230 a and 230 b in the magnetoresistive element 25 is connected at the connection point 34, and one end of each of the magnetic resistances 230 c and 230 d is connected at the connection point 35.
  • the other ends of the magnetic resistors 230a and 230d are connected to the power source Vcc, and the other ends of the magnetic resistors 230b and 230c are connected to the ground.
  • the magnetic resistances 230a and 230b are connected in series with each other, and the magnetic resistances 230d and 230c are connected in series with each other.
  • connection point 32 and the connection point 33 are connected to the non-inverting input terminal and the inverting input terminal of the differential amplifier 123, respectively.
  • connection point 34 and the connection point 35 are connected to the non-inverting input terminal and the inverting input terminal of the differential amplifier 125, respectively.
  • the output of the differential amplifier 123 and the output of the differential amplifier 125 are input to the adder 223.
  • the plane including the magnetic resistances 130a to 130d of the magnetoresistive element 23, that is, the surface 131b of the insulating substrate 131 and the plane including the magnetic resistances 230a to 230d of the magnetoresistive element 25, that is, the surface 231a of the insulating substrate 231 are parallel to each other. 22 in parallel.
  • the magnetoresistive elements 23 and 25 are arranged so that the distance between the surface 131 b and the current path 22 is equal to the distance between the surface 231 a and the current path 22.
  • a straight line passing through the center 131c of the surface 131b of the insulating substrate 131 of the magnetoresistive element 23 and passing through the center of the magnetic field generator 24 through the center 131c of the insulating substrate 131 is close to the magnetoresistive element 23 and the magnetic field generator 24.
  • a straight line that passes through the center 231c of the surface 231a of the insulating substrate 231 of the magnetoresistive element 25 and passes through the center of the magnetic field generator 26 passes through the center of the magnetic field generator 26, and the magnetoresistive element 25 and the magnetic field generator It is desirable to arrange them so that they are close to each other.
  • the center 131c of the surface 131b of the insulating substrate 131 is specifically the center of the bridge where the four magnetic resistors 130a to 130d are arranged, and specifically the center 231c of the surface 231a of the insulating substrate 231. Is the center of the bridge where the four magnetoresistors 230a-230d are arranged.
  • the magnetoresistive elements 23 and 25 can be given a uniform and high magnetic flux density, and the current flowing through the current path 22 can be measured with higher accuracy.
  • a magnetic flux density vector Bm 1 from the magnetic field generator 24 is applied to the magnetoresistive element 23 in the negative direction of the Z axis
  • a magnetic flux density vector Bm 2 from the magnetic field generator 26 is applied to the magnetoresistive element 25 in the positive direction of the Z axis. Is applied.
  • the magnetic sensing direction which is the direction of the magnetic field detected by the magnetic resistors 130a to 130d, is perpendicular to the direction of the current flowing through the magnetic resistors 130a to 130d and is parallel to the surface 131b of the insulating substrate 131.
  • the magnetic sensing direction which is the direction of the magnetic field detected by the magnetic resistors 230a to 230d, is perpendicular to the direction of the current flowing through the magnetic resistors 230a to 230d and is parallel to the surface 231a of the insulating substrate 231.
  • the change in the resistance value of the magnetic resistances 230a to 230d with respect to the change in the magnetic field in the magnetic sensing direction becomes the largest.
  • the resistance values of the magnetic resistors 130a to 130d and 230a to 230d decrease.
  • the resistance value of the magnetoresistive 130a ⁇ 130d are decreased uniformly by the action of the magnetic flux density vector Bm 1, the resistance value of the magnetoresistive 230a ⁇ 230d magnetic flux density vector Bm It decreases uniformly by the action of 2 .
  • Magnetoresistive 130a, and the product of the resistance value of 130c, magnetoresistive 130b, the product of the resistance value of 130d is set to be equal, constituted by magnetoresistive 130a ⁇ 130d also act magnetic flux density vector Bm 1 Since the full bridge circuit to be balanced is balanced, the output V OUT1 of the differential amplifier 125 becomes zero.
  • magnetoresistive 230a and the product of the resistance value of 230c magnetoresistive 230b, the product of the resistance value of 230d is set to be equal, the magnetoresistive 230a ⁇ also act magnetic flux density vector Bm 2 Since the full bridge circuit composed of 230d is balanced, the output V OUT2 of the differential amplifier 125 becomes zero.
  • the output of the adder 223 that adds the outputs V OUT1 and V OUT2 of the differential amplifiers 123 and 125 remains at a so-called zero point potential of Vcc / 2, for example.
  • the magnetic flux density vector Bc 1 facing the positive direction of the X axis is further applied to the magnetoresistive element 23. That is, the magnetoresistive element 23 and the magnetic flux density vector Bm 1 from the magnetic field generator 24, the synthetic magnetic flux density vector B 1 obtained by combining the magnetic flux density vector Bc 1 by the measured current Id is applied.
  • the resultant magnetic flux density vector B 1 forms an angle ⁇ 1 with the magnetic flux density vector Bm 1 .
  • the magnetic resistance element 25 is further applied with a magnetic flux density vector Bc 2 directed in the negative direction of the X axis.
  • a combined magnetic flux density vector B 2 obtained by combining the magnetic flux density vector Bm 2 from the magnetic field generator 26 and the magnetic flux density vector Bc 2 by the measured current Id is applied to the magnetoresistive element 25.
  • the resultant magnetic flux density vector B 2 forms an angle ⁇ 2 with the magnetic flux density vector Bm 2 .
  • the magnetic field intensity generated by the magnetic field generator 24, the magnetic field intensity generated by the magnetic field generator 26, and the magnetic field generator 24 so that the magnitude of the magnetic flux density vector Bm 1 matches the magnitude of the magnetic flux density vector Bm 2.
  • the distance between the magnetoresistive element 23 and the distance between the magnetic field generator 26 and the magnetoresistive element 25 are adjusted.
  • the plane (surface 131b) including the magnetic resistances 130a to 130d of the magnetoresistive element 23 and the plane (surface 231a) including the magnetic resistances 230a to 230d of the magnetoresistive element 25 are arranged in parallel to the current path 22.
  • the distance between the plane (surface 131b) including the magnetic resistances 130a to 130d of the magnetoresistive element 23 and the current path 22 is equal to the plane (plane 231a) including the magnetic resistances 230a to 230d of the magnetoresistive element 25 and the current path 22. It is arranged to be equal to the distance.
  • the magnitudes of the magnetic flux density vectors Bc 1 and Bc 2 are constant in the planes (surfaces 131b and 231a) of the magnetoresistive elements 23 and 25 and are equal to each other. Therefore, the combined magnetic flux density vectors B 1 and B 2 in the surfaces 131b and 231a of the magnetoresistive elements 23 and 25 are the same in size and different in direction by 180 degrees.
  • the magnetic resistances 130a to 130d and 230a to 230d show the same resistance value in the absence of a magnetic field, and the amount of change in the resistance value with respect to the applied magnetic field is the same.
  • variation occurs, but the smaller the variation, the better.
  • Magnetoresistive 130a ⁇ 130d are so insensitive direction of the magnetic field of the current flowing through the magnetoresistive 130a ⁇ 130d, the change in the resistance value and the synthetic magnetic flux density vector B 1 is closer to the current direction parallel through the magnetoresistive 130a ⁇ 130d The amount, i.e. the amount of decline, decreases.
  • Direction of the synthetic magnetic flux density vector B 1 is the resistance value of the magnetoresistive 130a ⁇ 130d approaches the direction perpendicular to the direction of the current flowing through the magnetoresistive 130a ⁇ 130d is lowered more significantly.
  • magnetoresistive 230a ⁇ 230d are so insensitive direction of the magnetic field of the current flowing through the magnetoresistive 230a ⁇ 230d includes a synthetic magnetic flux density vector B 2 approaches the current direction parallel through the magnetoresistive 230a ⁇ 230d resistor
  • the amount of change that is, the amount of decrease, decreases.
  • Direction of the synthetic magnetic flux density vector B 2 is the resistance value of the magnetoresistive 230a ⁇ 230d approaches the direction perpendicular to the direction of the current flowing through the magnetoresistive 230a ⁇ 230d is lowered more significantly.
  • the magnitude and magnetic characteristics of the magnetic field generators 24 and 26 are made the same, and the magnetic field generator 24 and the magnetoresistive element 23 It is preferable that the distance is equal to the distance between the magnetic field generator 26 and the magnetoresistive element 25.
  • the magnetic flux density vectors Bc 1 and Bc 2 increase, so that the resistance values of the magnetoresistances 130a and 130c of the magnetoresistive element 23 decrease and the resistance values of the magnetoresistances 130b and 130d increase.
  • the potential at the connection point 32 increases and the potential at the connection point 33 decreases.
  • the balance of the full bridge circuit is lost, and the output V OUT1 of the differential amplifier 123 is generated.
  • the resistance values of the magnetic resistors 230a and 230c of the magnetoresistive element 25 are decreased, and the resistance values of the magnetic resistors 230b and 230d are increased.
  • the output of the adder 223 that adds the outputs V OUT1 and V OUT2 of the differential amplifiers 123 and 125 is, for example, a voltage V 2 (V 2 ⁇ V ⁇ 2 ) that is larger than the zero point potential of Vcc / 2 and smaller than the voltage V 1. V 1 ).
  • V 2 V 2 ⁇ V ⁇ 2
  • the current sensor 21 in the embodiment can accurately detect the measured current Id flowing in the current path 22 without contact.
  • FIG. 3A is a side view of the current sensor 121 of the example in the embodiment.
  • 3B is a cross-sectional view taken along line 3B-3B of current sensor 121 shown in FIG. 3A.
  • the current path 40 is a copper round bar having a diameter of 3 mm extending in the Z-axis direction.
  • a current Id to be measured flows through the current path 40 in the negative direction of the Z axis.
  • a magnetoresistive element 41 and a magnetic field generator 42 that applies a bias magnetic field to the magnetoresistive element 41 are disposed above the current path 40, that is, in the positive direction of the Y axis.
  • the magnetic field generator 42 is disposed immediately above the magnetoresistive element 41.
  • a magnetoresistive element 43 and a magnetic field generator 44 that applies a bias magnetic field to the magnetoresistive element 43 are disposed below the current path 40, that is, in the negative direction of the Y axis.
  • the magnetic field generator 42 is disposed immediately below the magnetoresistive element 43.
  • the magnetic field generators 42 and 44 are magnets.
  • the magnetic field 45 is generated by the measured current Id flowing through the current path 40 and circulates around the current path 40.
  • Magnetic fields 46 and 47 are generated around the magnetic field generators 42 and 44, respectively.
  • the direction from the center of the N pole 42N to the center of the S pole 42S of the magnetic field generator 42 coincides with the negative direction of the Z axis, and the direction from the center of the S pole 44S to the center of the N pole 44N of the magnetic field generator 44 is the same.
  • Magnetic field generators 42 and 44 are arranged so as to coincide with the negative direction of the Z-axis.
  • the magnetic field generator 42 gives a bias magnetic field to the magnetoresistive element 41 in a direction coinciding with the direction in which the current Id to be measured flows.
  • the magnetic field generator 44 applies a bias magnetic field to the magnetoresistive element 43 in a direction opposite to the direction of the bias magnetic field applied to the magnetoresistive element 41.
  • the magnetic field generators 42 and 44 are so-called rubber magnets, each having a length and width of 3 mm and a thickness of 0.4 mm, in which ferrite powder is kneaded and molded in rubber, and those having a surface magnetic flux density of 200 gauss are used.
  • FIG. 4A is a bottom view of the magnetoresistive element 41
  • FIG. 4B is a cross-sectional view of the magnetoresistive element 41 taken along line 4B-4B shown in FIG. 4A.
  • the lengths of the magnetoresistive element 41 in the X-axis, Y-axis, and Z-axis directions are 3 mm, 0.8 mm, and 3 mm, respectively.
  • the magnetoresistive element 41 includes an insulating substrate 150 made of an insulating member such as ceramic, a power application electrode 151, output electrodes 152 and 153, a ground electrode 154, magnetic resistors 155a to 155d, and an insulating layer 160.
  • the power application electrode 151, the output electrodes 152 and 153, the ground electrode 154, and the magnetic resistors 155a to 155d are provided on the lower surface 150b of the insulating substrate 150.
  • the magnetic resistance 155 a is formed of a meandering magnetic resistor, is provided between the power application electrode 151 and the output electrode 152, and is connected between the power application electrode 151 and the output electrode 152.
  • the magnetoresistor 155b is formed of a meandering magnetoresistor, is provided between the output electrode 152 and the ground electrode 154, and is connected between the output electrode 152 and the ground electrode 154.
  • the magnetoresistor 155c is formed of a meandering magnetoresistor, is provided between the output electrode 153 and the ground electrode 154, and is connected between the output electrode 153 and the ground electrode 154.
  • the magnetic resistance 155 d is formed of a meandering magnetic resistor, is provided between the power supply application electrode 151 and the output electrode 153, and is connected between the power supply application electrode 151 and the output electrode 153. By making such electrical connection, the magnetic resistors 155a to 155d constitute a bridge circuit.
  • the magnetic resistors 155a to 155d are made of a magnetoresistive thin film made of a ferromagnetic material such as Ni—Co and having a thickness of about 0.1 ⁇ m. As shown in FIG.
  • the longitudinal direction of the meandering pattern of the magnetoresistive 155a is between the positive direction of the Z axis and the positive direction of the X axis, which is the direction of the current Id to be measured. It extends between the negative direction and is inclined 45 ° with respect to the Z axis.
  • the magnetic resistance 155a extends in a magnetic sensitive direction perpendicular to the longitudinal direction of the magnetic resistance 155a while meandering, and detects a magnetic field in the magnetic sensitive direction.
  • the longitudinal direction of the meandering pattern of the magnetic resistance 155b adjacent to the magnetic resistance 155a is inclined by 45 ° with respect to the Z axis and is perpendicular to the longitudinal direction of the magnetic resistance 155a.
  • the magnetic resistance 155b extends in a magnetic sensing direction perpendicular to the longitudinal direction of the magnetic resistance 155b while meandering, and detects a magnetic field in the magnetic sensing direction.
  • the longitudinal direction of the meandering pattern of the magnetic resistance 155c adjacent to the magnetic resistance 155b is inclined by 45 ° with respect to the Z axis and perpendicular to the longitudinal direction of the magnetic resistance 155b.
  • the magnetic resistance 155c extends in a magnetic sensing direction perpendicular to the longitudinal direction of the magnetic resistance 155c while meandering, and detects a magnetic field in the magnetic sensing direction.
  • the magnetic sensing direction of the magnetic resistance 155a and the longitudinal direction of the meander pattern coincide with those of the magnetic resistance 155c.
  • the longitudinal direction of the meandering pattern of the magnetic resistance 155d adjacent to the magnetic resistances 155a and 155c is inclined by 45 ° with respect to the Z-axis and is perpendicular to the longitudinal direction of the magnetic resistances 155a and 155c.
  • the magnetic resistance 155d extends in a magnetic sensitive direction perpendicular to the longitudinal direction of the magnetic resistances 155a and 155c while meandering, and detects a magnetic field in the magnetic sensitive direction.
  • the magnetic sensing direction of the magnetic resistance 155d and the longitudinal direction of the meander pattern coincide with those of the magnetic resistance 155b.
  • the magnetic resistances 155a to 155d sense a magnetic field along the lower surface 150b of the insulating substrate 150.
  • the insulating layer 160 is an SiO 2 thin film having a thickness of about 1 ⁇ m provided on the lower surface 150b of the insulating substrate 150, and protects the magnetic resistances 155a to 155d by covering the magnetic resistances 155a to 155d.
  • FIG. 4C is a top view of the magnetoresistive element 43
  • FIG. 4D is a cross-sectional view taken along line 4D-4D of the magnetoresistive element 43 shown in FIG. 4C.
  • the lengths of the magnetoresistive element 43 in the X-axis, Y-axis, and Z-axis directions are 3 mm, 0.8 mm, and 3 mm, respectively.
  • the magnetoresistive element 43 includes an insulating substrate 250 made of an insulating member such as ceramic, a power application electrode 251, output electrodes 252 and 253, a ground electrode 254, magnetic resistors 255 a to 255 d, and an insulating layer 260.
  • the power application electrode 251, the output electrodes 252 and 253, the ground electrode 254, and the magnetic resistances 255 a to 255 d are provided on the upper surface 250 a of the insulating substrate 250.
  • the magnetoresistor 255a is formed of a meandering magnetoresistor and is provided between the power supply application electrode 251 and the output electrode 252 and connected between the power supply application electrode 251 and the output electrode 252.
  • the magnetoresistor 255b is formed of a meandering magnetoresistor, is provided between the output electrode 252 and the ground electrode 254, and is connected between the output electrode 252 and the ground electrode 254.
  • the magnetoresistor 255c is formed of a meandering magnetoresistor, is provided between the output electrode 253 and the ground electrode 254, and is connected between the output electrode 253 and the ground electrode 254.
  • the magnetoresistor 255d is a meandering magnetic resistor, is provided between the power supply application electrode 251 and the output electrode 253, and is connected between the power supply application electrode 251 and the output electrode 253.
  • the magnetic resistances 255a to 255d constitute a bridge circuit.
  • the magnetic resistances 255a to 255d are made of a magnetoresistive thin film made of a ferromagnetic material such as Ni—Co and having a thickness of about 0.1 ⁇ m. As shown in FIG.
  • the longitudinal direction of the meandering pattern of the magnetoresistive 255a is between the positive direction of the Z axis and the positive direction of the X axis, which is the direction of the current Id to be measured, and the negative direction of the Z axis and the X axis. It extends between the negative direction and is inclined 45 ° with respect to the Z axis.
  • the magnetic resistance 255a extends in a magnetic sensing direction perpendicular to the longitudinal direction of the magnetic resistance 255a while meandering, and detects a magnetic field in the magnetic sensing direction.
  • the longitudinal direction of the meandering pattern of the magnetic resistance 255b adjacent to the magnetic resistance 255a is inclined by 45 ° with respect to the Z axis and is perpendicular to the longitudinal direction of the magnetic resistance 255a.
  • the magnetic resistance 255b extends in a magnetic sensitive direction perpendicular to the longitudinal direction of the magnetic resistance 255b while meandering, and detects a magnetic field in the magnetic sensitive direction.
  • the longitudinal direction of the meandering pattern of the magnetic resistance 255c adjacent to the magnetic resistance 255b is inclined by 45 ° with respect to the Z axis and perpendicular to the longitudinal direction of the magnetic resistance 255b.
  • the magnetic resistance 255c extends in a magnetic sensing direction perpendicular to the longitudinal direction of the magnetic resistance 255c while meandering, and detects a magnetic field in the magnetic sensing direction.
  • the magnetic sensing direction of the magnetic resistance 255a and the longitudinal direction of the meander pattern coincide with those of the magnetic resistance 255c.
  • the longitudinal direction of the meander pattern of the magnetoresistor 255d adjacent to the magnetoresistors 255a and 255c is inclined by 45 ° with respect to the Z axis and is perpendicular to the longitudinal direction of the magnetoresistors 255a and 255c.
  • the magnetic resistance 255d extends in a magnetic sensitive direction perpendicular to the longitudinal direction of the magnetic resistances 255a and 255c while meandering, and detects a magnetic field in the magnetic sensitive direction.
  • the magnetic sensing direction of the magnetic resistance 255d and the longitudinal direction of the meander pattern coincide with those of the magnetic resistance 255b.
  • the magnetic resistances 255a to 255d sense a magnetic field along the upper surface 250a of the insulating substrate 250.
  • the insulating layer 260 is formed of a SiO 2 thin film having a thickness of about 1 ⁇ m provided on the upper surface 250a of the insulating substrate 250, and protects the magnetic resistances 255a to 255d by covering the magnetic resistances 255a to 255d.
  • FIG. 4E is a circuit diagram of the current sensor 121.
  • the power application electrode 151 and the ground electrode 154 of the magnetoresistive element 41 are connected to the power supply Vcc and the ground, respectively.
  • the output electrodes 152 and 153 of the magnetoresistive element 41 are connected to the non-inverting input terminal and the inverting input terminal of the differential amplifier 141, respectively.
  • the differential amplifier 141 outputs a difference signal obtained by subtracting the signal input to the inverting input terminal from the signal input to the non-inverting input terminal.
  • the power application electrode 251 and the ground electrode 254 of the magnetoresistive element 43 are connected to the power supply Vcc and the ground, respectively.
  • the output electrodes 252 and 253 of the magnetoresistive element 43 are connected to the non-inverting input terminal and the inverting input terminal of the differential amplifier 143, respectively.
  • the differential amplifier 143 outputs a difference signal obtained by subtracting the signal input to the inverting input terminal from the signal input to the non-inverting input terminal.
  • the outputs of the differential amplifiers 141 and 143 are connected to the adder 241.
  • the adder 241 adds the signals output from the differential amplifiers 141 and 143 and outputs the result.
  • the plane including the magnetic resistances 155a to 155d of the magnetoresistive element 41, that is, the lower surface 150b of the insulating substrate 150, and the plane including the magnetic resistances 255a to 255d of the magnetoresistive element 43, that is, the upper surface 250a of the insulating substrate 250 are arranged in parallel with the current path 40.
  • the distance between the lower surface 150b of the insulating substrate 150 of the magnetoresistive element 41 and the current path 40 and the distance between the upper surface 250a of the insulating substrate 250 of the magnetoresistive element 43 and the current path 40 are equal to each other and 1.76 mm.
  • the entire current sensor 121 was arranged at the center on the central axis in the Helmholtz coil. Initially, when no current was applied to the Helmholtz coil and a current of 10 amperes was passed through the current path 40, the output of the adder 241 was 2.77 volts. At this time, the magnetic flux density of the current magnetic field applied to the magnetoresistive elements 41 and 43 is about 0.2 mT. Next, with the central axis of the Helmholtz coil and the current direction of the current path 40 orthogonal to each other and a current of 10 amperes flowing in the current path 40, a current is passed through the Helmholtz coil, so that the X in FIG. 3A and FIG. An external magnetic field parallel to the current magnetic field applied to the magnetoresistive elements 41 and 43 by the measured current Id flowing through the current path 40 in the axial direction was applied to the magnetoresistive elements 41 and 43.
  • FIG. 5A shows the evaluation result of the current sensor 121. Specifically, by adjusting the current passed through the Helmholtz coil, the magnetic flux density of the external magnetic field facing the X-axis direction shown in FIGS. 3A and 3B is set to 0 mT (Tesla). The output change rate of the adder 241 when changing from 1 to 2 mT is shown.
  • the direction of the current of the current path 40 is made to coincide with the central axis of the Helmholtz coil, and a current of 10 amperes is passed through the current path 40, whereby a current is passed through the Helmholtz coil, as shown in FIGS. 3A and 3B.
  • An external magnetic field orthogonal to the current magnetic field 45 applied to the magnetoresistive elements 41 and 43 by the measured current Id flowing through the current path 40 in the Z-axis direction was applied to the magnetoresistive elements 41 and 43.
  • FIG. 5B shows the output change of the adder 241 when the current flowing through the Helmholtz coil is adjusted to change the magnetic flux density of the external magnetic field facing the Z-axis direction shown in FIGS. 3A and 3B from 0 mT (Tesla) to 2 mT. Indicates the rate.
  • the error voltage generated when an external magnetic field of 0.5 mT, which is 5 times, is applied is 0.05% or less. Even when a 2 mT external magnetic field corresponding to 10 times the magnetic flux density of the current magnetic field is applied, the generated error voltage is 0.15% or less.
  • the current sensor 121 has an extremely small error in the current value of the measured current Id even when an external magnetic field is present, and accurately measures the measured current Id flowing in the current path 40 in a non-contact manner. it can.
  • the magnetoresistive elements 5a and 6a are arranged in a plane (XY plane) perpendicular to the measured current Id flowing through the current path 4, the current sensor The dimension in the Y-axis direction becomes large.
  • the magnetoresistive elements 5a and 6a are arranged in a plane perpendicular to the measured current Id flowing through the current path 4, and the magnetoresistances Ra to Rd are respectively directed to the magnetization easy axis and the direction of the induced magnetic field generated by the measured current Id. Therefore, there is a limit to disposing the magnetoresistive elements 5a and 6a close to the current path 4.
  • the magnetic flux density generated by the measured current Id flowing in the current path 4 decreases in inverse proportion to the distance from the current path 4, so that the magnetic flux density in the magnetoresistive elements 5a and 6a is not uniform. For this reason, if the positions of the magnetic resistances Ra and Rb vary, an error occurs in the resistance change of the bridge circuit composed of the magnetoresistive elements 5a and 6a, and an error occurs in the measured current value.
  • the surface 150b which is a plane including the magnetic resistances 155a to 155d of the magnetoresistive element 41 and the surface 250a which is a plane including the magnetic resistances 255a to 255d of the magnetoresistive element 43 are connected to the current path 40. Since they are arranged in parallel, the dimension of the current sensor 121 in the Y-axis direction can be reduced. Further, since the magnetoresistive elements 41 and 43 can be arranged close to the current path 40, the current sensor 121 effectively detects the magnetic field generated by the measured current Id flowing through the current path 40 and increases the S / N ratio. Can do.
  • the magnetic field generators 42 and 44 are brought close to each other, and the attractive force acting between the N pole 42N of the magnetic field generator 42 and the S pole 44S of the magnetic field generator 44, and the S pole 42S of the magnetic field generator 42 and the magnetic field generator
  • the magnetoresistive elements 41 and 43 can be easily attached to the current path 40 by the attractive force acting between the 44 N poles 44N. Further, since the magnetic flux density generated by the measured current Id flowing in the current path 40 is constant in the magnetoresistive elements 41 and 43, the planes of the magnetic resistors 155a to 155d and 255a to 255d constituting the magnetoresistive elements 41 and 43, respectively. The restriction on the position in the (surfaces 150b, 250a) can be eliminated.
  • the distance between the plane (surface 150b) of the magnetoresistive element 41 including the magnetic resistances 155a to 155d and the current path 40 is equal to the plane (plane 250a) of the magnetoresistive element 43 including the magnetic resistances 255a to 255d and the current path 40. Therefore, even if an external magnetic field exists, the current sensor 121 does not cause an error in the current value of the current Id to be measured, and the current path 40 is contactless. It is possible to accurately measure the current to be measured Id flowing through the.
  • the magnetic resistances 130a to 130d of the magnetoresistive element 23 are connected to the full bridge, and the magnetic resistances 230a to 230d of the magnetoresistive element 25 are connected to the full bridge.
  • the magnetic resistances 155a to 155d of the magnetoresistive element 41 are connected to the full bridge, and the magnetic resistances 255a to 255d of the magnetoresistive element 43 are connected to the full bridge. The same effect can be obtained even if the magnetic resistances 155a to 155d of the magnetoresistive element 41 are connected to the half bridge and the magnetic resistances 255a to 255d of the magnetoresistive element 43 are connected to the half bridge.
  • FIG. 6A is a plan view of another magnetoresistive element 71 of the current sensor 121 in the embodiment.
  • 6B is a cross-sectional view taken along line 6B-6B of the magnetoresistive element 71 shown in FIG. 6A.
  • FIG. 6C is a plan view of another magnetoresistive element 73.
  • 6D is a cross-sectional view of the magnetoresistive element 73 shown in FIG. 6C taken along line 6D-6D.
  • 6A to 6D the same reference numerals are assigned to the same portions as those of the magnetoresistive elements 41 and 43 shown in FIGS. 4A to 4D.
  • 6A and 6B is arranged on the plurality of thin film magnets 161 arranged on the lower surface 160b of the insulating layer 160 of the magnetoresistive element 41 shown in FIGS. 4A and 4B, and on the lower surface 160b of the insulating layer 160. And an insulating layer 162 covering the thin film magnet 161.
  • 6C and 6D are disposed on the upper surface 260a of the insulating layer 260 and the plurality of thin film magnets 261 disposed on the upper surface 260a of the insulating layer 260 of the magnetoresistive element 43 illustrated in FIGS. 4C and 4D.
  • an insulating layer 262 that covers the thin film magnet 261.
  • the thin film magnets 161 and 261 are made of a magnetic material such as CoPt having a thickness of about 0.6 ⁇ m. After forming a thin film of the magnetic material on the entire surfaces 160b and 260a of the insulating layers 160 and 260 by vapor deposition, sputtering, or the like, exposure is performed. It is formed by patterning those thin films by etching.
  • the plurality of thin film magnets 161 has a substantially rectangular shape elongated in the direction of 45 degrees with the direction of magnetic resistance of the magnetic resistances 155a to 155d, specifically in the X-axis direction, and is arranged in the Z-axis direction. ing.
  • the plurality of thin-film magnets 261 have a substantially rectangular shape extending in the direction of 45 degrees with the direction of the magnetic resistance of the magnetic resistances 255a to 255d, specifically the X-axis direction, and are arranged in the Z-axis direction. ing.
  • the thin film magnets 161 and 261 are magnetized in the width direction, that is, the direction of the Z axis that is the direction of the current Id to be measured.
  • the thin film magnet 161 functions as a magnetic field generator that gives the magnetoresistive element 71 a bias magnetic field in a direction that coincides with the direction in which the measured current Id flows.
  • the thin film magnet 261 functions as a magnetic field generator that applies a bias magnetic field in a direction opposite to the direction of the bias magnetic field applied to the magnetoresistive element 71 to the magnetoresistive element 73.
  • the insulating layers 162 and 262 are made of SiO 2 thin film having a thickness of about 1 ⁇ m, and the thin film magnets 161 and 261 are protected by covering the thin film magnets 161 and 261, respectively. According to this configuration, the magnetic resistances 155a to 155d and 255a to 255d of the magnetoresistive elements 71 and 73 can be given a more uniform and high magnetic flux density. Furthermore, since the thin film magnets 161 and 261 can be formed integrally with the magnetoresistive elements 71 and 73, respectively, an extremely small current sensor 121 can be obtained.
  • FIG. 6E is a side view of a current sensor 221 of another example in the embodiment using the magnetoresistive elements 71 and 73 shown in FIGS. 6A to 6D.
  • the current sensor 221 includes the thin film magnets 161 and 261 shown in FIGS. 6A to 6D instead of the magnetoresistive elements 41 and 42 of the current sensor 121 shown in FIG. 3A, and does not include the magnetic field generators 42 and 44 shown in FIG. 3A.
  • the thin film magnet 161 shown in FIGS. 6A and 6B functions as the magnetic field generator 42 shown in FIG.
  • the thin film magnet 261 shown in FIGS. 6C and 6D functions as the magnetic field generator 44 shown in FIG. 3A, and applies the same magnetic field as the magnetic field applied by the magnetic field generator 44 to the magnetic resistors 255a to 255d.
  • the current sensor 221 operates in the same manner as the current sensor 121 and can accurately measure the measured current Id.
  • connection between the inverting input terminal and the non-inverting input terminal of the differential amplifier may be the reverse of the above.
  • terms indicating directions such as “upper”, “lower”, “above”, “below”, “upper surface”, and “lower surface” are relative positions of current sensor components such as current paths and magnetoresistive elements. It indicates the relative direction depending only on the relationship, and does not indicate the absolute direction such as the vertical direction.
  • the current sensor according to the present invention can be reduced in size and can accurately measure the current flowing in the current path in a non-contact manner, and is particularly useful as a current detection device that detects current in vehicles, industrial equipment, and the like. It is.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
  • Measuring Magnetic Variables (AREA)

Abstract

La présente invention concerne un capteur de courant qui est doté : d'un trajet de courant qui est conçu de sorte qu'un courant devant être mesuré circule dans celui-ci ; de premier et second éléments magnétorésistants, le trajet de courant étant disposé entre eux ; et de premier et second générateurs de champ magnétique, qui appliquent respectivement des premier et second champs magnétiques de polarisation aux premier et second éléments magnétorésistants, lesdits premier et second champs magnétiques de polarisation étant dans la direction correspondant à la direction de circulation du courant devant être mesuré. Le capteur de courant est conçu pour détecter, sur la base de signaux de sortie des premier et second éléments magnétorésistants, le courant devant être mesuré. Les premier et second éléments magnétorésistants possèdent respectivement des premier et second corps magnétorésistants qui sont disposés le long de premier et second plans parallèles au trajet de courant. La distance entre le premier plan et le trajet de courant est égale à la distance entre le second plan et le trajet de courant. Le capteur de courant est de petite taille, et est capable de mesurer avec précision le courant circulant dans le trajet de courant.
PCT/JP2013/003276 2012-05-31 2013-05-23 Capteur de courant Ceased WO2013179613A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2012-124096 2012-05-31
JP2012124096A JP2015155796A (ja) 2012-05-31 2012-05-31 電流センサ

Publications (1)

Publication Number Publication Date
WO2013179613A1 true WO2013179613A1 (fr) 2013-12-05

Family

ID=49672840

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2013/003276 Ceased WO2013179613A1 (fr) 2012-05-31 2013-05-23 Capteur de courant

Country Status (2)

Country Link
JP (1) JP2015155796A (fr)
WO (1) WO2013179613A1 (fr)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018092580A1 (fr) * 2016-11-16 2018-05-24 株式会社村田製作所 Capteur de courant
DE102021127855A1 (de) * 2021-06-11 2022-12-22 Methode Electronics Malta Ltd. Stromsensor, der einen Magnetfeldsensor in einer V-förmigenAnordnung umfasst

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006162360A (ja) * 2004-12-06 2006-06-22 Tdk Corp 電流センサ
JP2007101253A (ja) * 2005-09-30 2007-04-19 Tdk Corp 電流センサ

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006162360A (ja) * 2004-12-06 2006-06-22 Tdk Corp 電流センサ
JP2007101253A (ja) * 2005-09-30 2007-04-19 Tdk Corp 電流センサ

Also Published As

Publication number Publication date
JP2015155796A (ja) 2015-08-27

Similar Documents

Publication Publication Date Title
EP2442117B1 (fr) Capteur de courant à équilibre magnétique
US8487612B2 (en) Current sensor
JP6107942B2 (ja) 磁気電流センサおよび電流測定方法
US8269492B2 (en) Magnetic balance type current sensor
JP5888402B2 (ja) 磁気センサ素子
CN1659444A (zh) 用于测量带电粒子电流的传感器和方法
JP6299069B2 (ja) 磁気センサ装置
JP5439595B2 (ja) 磁界角計測装置およびこれを用いた回転角計測装置
JP2012063203A (ja) 磁気センサ
CN110837066A (zh) 磁场感测装置
WO2013179613A1 (fr) Capteur de courant
WO2013105489A1 (fr) Capteur de courant
US11815571B2 (en) Electric current sensor and sensing device
JP2013047610A (ja) 磁気平衡式電流センサ
CN114460347B (zh) 电流传感器及电气控制装置
EP3851864B1 (fr) Capteur magnétique et capteur de courant
JP5793681B2 (ja) 電力計測装置
WO2012063584A1 (fr) Capteur de courant
JP6285641B2 (ja) 磁気センサ及び磁場成分演算方法
JP2012073034A (ja) 電力計測装置および電力計測方法
WO2016111278A1 (fr) Capteur de courant
JP2015034774A (ja) 電流検出システム、電流検出方法、及び充電制御装置
CN120065081A (zh) 磁传感器及电流传感器
JP2015031647A (ja) 電流センサおよびその製造方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 13796319

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 13796319

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP