JP2005195427A - Current measurement system, current measurement method, and current measurement program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase the accuracy of measuring a current flowing through a conductor to be measured while relaxing restrictions on the placement of a magnetic sensor and the shape of the conductor to be measured. <P>SOLUTION: Integrated magnetic sensors 2a, 2b incorporate magnetic sensors 3a, 3b of which the magnetic surfaces are in parallel with each other and signal processing sections 4a, 4b which calculate the value of a current I flowing through the conductor to be measured 5 based on output signals from the magnetic sensors 3a, 3b. The value of the current I flowing through the conductor to be measured 5 is calculated based on the current sensitivity of the magnetic sensors 3a, 3b. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a current measuring device and a current measuring method for measuring the magnitude of a current flowing through a conductor to be measured using a magnetic sensor, and in particular, a current measuring device in which a plurality of magnetic sensors are arranged close to a conductor to be measured, The present invention relates to a current measurement method and a current measurement program.

As a conventional technique for measuring the magnitude of a current flowing through a conductor, a current measuring method using a magnetic sensor is known. In a magnetic sensor, a magnetic detection element is provided inside the sensor, and a voltage proportional to the magnitude of a magnetic field input to the magnetic detection element is output.
When measuring the current using this magnetic sensor, the magnitude of the current flowing through the conductor is measured by arranging the magnetic sensor around the conductor and detecting the induced magnetic field caused by the current flowing through the conductor with the magnetic sensor. be able to.

In addition, there is a current measurement device that measures the magnitude of current by disposing a surface-mountable magnetic sensor on a substrate having a conductor to be measured. In this current measuring device, the magnetic sensor can detect a magnetic field parallel to the mounting surface. For this reason, the magnitude | size of the electric current which flows into a conductor can be measured by arrange | positioning a magnetic sensor on a to-be-measured conductor, and detecting the magnetic field produced in the width direction of a conductor with a magnetic sensor.
Further, for example, Patent Document 1 discloses a method of using two magnetic sensors in order to reduce the influence of a disturbing magnetic field when measuring a current flowing through a conductor with a magnetic sensor.
JP 2001-153895 A

However, in the method disclosed in Patent Document 1, there are restrictions on the arrangement position of the magnetic sensor and the shape of the conductor to be measured.
That is, in the method disclosed in Patent Document 1, in order to match the output of the magnetic sensor with respect to the disturbance magnetic field, the conductor to be measured is sandwiched so that the two magnetic sensors are arranged on the same circumference. It is necessary to make the current sensitivities of the magnetic sensors equal to each other. If the arrangement of these magnetic sensors deviates from the same circumference, the disturbance magnetic field is different in magnitude and direction, so that the disturbance magnetic field cannot be canceled and the current measurement accuracy deteriorates.

In addition, if the position of the magnetic sensor and the shape of the conductor to be measured are restricted, the size and shape of the current measuring device are restricted, or the magnetic sensor is placed at regular intervals with respect to the conductor to be measured. There is a problem that a jig or a spacer is required.
Further, the current sensitivity of the magnetic sensor is greatly influenced by the magnetic sensitivity of the Hall element and the distance of the conductor to be measured. For this reason, in order to accurately measure the current flowing through the conductor to be measured, it is necessary to arrange two magnetic sensors accurately and to equalize the current sensitivity to the current flowing through the conductor to be measured. The measurement accuracy is greatly affected by variations in the current sensitivity of the magnetic sensor.

Furthermore, in the method disclosed in Patent Document 1, excellent measurement accuracy can be achieved when the conductor to be measured is a cylindrical (or linear) conductor (or conductor), but the shape of the object to be measured is other than a cylinder. Measurement of the current flowing through the conductor was not considered.
Accordingly, an object of the present invention is to provide a current measuring apparatus, a current measuring method, and a current measuring apparatus capable of improving the measurement accuracy of a current flowing through a measured conductor while relaxing restrictions on the arrangement position of the magnetic sensor and the shape of the measured conductor. It is to provide a current measurement program.

In order to solve the above-described problem, according to the current measuring device according to claim 1, the current flows to the conductor under measurement based on a plurality of magnetic sensors and an output signal reflecting a difference in current sensitivity between the magnetic sensors. Signal processing means for calculating a current value.
As a result, when calculating the value of the current flowing through the conductor to be measured, the current sensitivities of the magnetic sensors can be made different from each other, and the current sensitivities of the magnetic sensors are made to coincide with each other in order to reduce the influence of the disturbance magnetic field. There is no need. For this reason, it becomes possible to improve the measurement accuracy of the current flowing through the conductor to be measured while relaxing restrictions on the arrangement position of the magnetic sensor and the shape of the conductor to be measured, thereby reducing the price and size of the magnetic sensor. Thus, it is possible to easily measure the current flowing through the conductor to be measured.

According to a second aspect of the present invention, the magnetic sensor includes a magnetoelectric conversion element having magnetic sensitive surfaces arranged in parallel to each other.
This makes it possible to easily match the magnitude and direction of the disturbance magnetic field with respect to the plurality of magnetic sensors, and cancel the disturbance magnetic field by taking the difference between the output signals from the plurality of magnetic sensors.
According to the current measuring device of the third aspect, the magnetic field sensitivities of the plurality of magnetic sensors are equal to each other.
Thereby, by taking the difference between the output signals from the plurality of magnetic sensors, the disturbance magnetic field can be canceled, and the measurement accuracy of the current flowing through the conductor to be measured can be improved.

According to a fourth aspect of the present invention, there is provided the current measuring device further comprising a base material on which the plurality of magnetic sensors are mounted such that the magnetic sensitive surfaces are parallel to each other.
As a result, the magnetic sensitive surfaces of the plurality of magnetic sensors can be made parallel to each other only by placing the base material in the vicinity of the measured conductor so that the magnetic sensor is asymmetric with respect to the measured conductor. The current sensitivities of the magnetic sensors can be made different from each other. For this reason, it is possible to measure the current flowing through the conductor to be measured while reducing the influence of the disturbance magnetic field, and to improve the measurement accuracy of the current flowing through the conductor to be measured. It is possible to easily measure the current flowing through the conductor to be measured while relaxing restrictions on the shape of the conductor.

According to the current measuring device of claim 5, the magnetic sensor is arranged parallel to the Hall element and the magnetic sensing surface of the Hall element, and generates a magnetic field generated by the current flowing through the conductor to be measured. And a magnetic converging plate for converging and guiding a vertical component of the converged magnetic field to the magnetic sensitive surface of the Hall element.
As a result, even when the magnetic sensing surface of the Hall element is arranged in parallel to the magnetic field generated from the conductor to be measured, the magnetic field generated from the conductor to be measured can be efficiently detected. While making it possible to arrange the magnetic sensor horizontally, the current flowing through the conductor to be measured can be accurately measured.

Further, according to the current measuring device of claim 6, the signal processing means includes magnetic field sensitivities of two magnetic sensors, current sensitivities of the two magnetic sensors, and the two magnetic sensors of the plurality of magnetic sensors. The value of the current flowing through the conductor to be measured is calculated based on the value of the output signal of the magnetic sensor.
Thereby, even when the current sensitivities of the magnetic sensors are different from each other, the value of the current flowing through the conductor to be measured can be calculated by the arithmetic processing, and the restrictions on the position of the magnetic sensor and the shape of the conductor to be measured are relaxed. Therefore, it is possible to easily measure the value of the current flowing through the conductor to be measured.

According to the current measuring device of claim 7, the current sensitivities of the two magnetic sensors are Sa and Sb [V / A], respectively, and the values of the output signals of the two magnetic sensors are Va. , Vb [V], the current value I [A] flowing through the conductor to be measured is I = (Va−Vb) / (Sa−Sb).
Thereby, the disturbance magnetic field can be canceled by taking the difference between the output signals from the plurality of magnetic sensors. Therefore, by using the current sensitivity of the magnetic sensor and the value of the output signal of the magnetic sensor, the value of the current flowing through the conductor to be measured can be calculated, and the measurement accuracy of the current flowing through the conductor to be measured is improved. Is possible.

Further, according to the current measuring device according to claim 8, the signal processing means is configured based on a known current value flowing through the conductor to be measured and output signal values of the two magnetic sensors at that time. It further comprises calibration means for preliminarily calculating a difference (Sa−Sb) in current sensitivity between the two magnetic sensors.
This makes it possible to easily obtain the difference in current sensitivity of the magnetic sensor, and to calculate the current flowing through the measured conductor without obtaining the individual current sensitivity of the magnetic sensor. It is possible to easily measure the current flowing through the.

According to the current measurement method of claim 9, the step of arranging a plurality of magnetic sensors so that the current sensitivities to the current flowing through the conductor to be measured are different from each other, and the step of capturing the output signal from the magnetic sensor; Calculating a value of a current flowing through the conductor to be measured based on output signals taken from the plurality of magnetic sensors.
As a result, when measuring the current flowing through the conductor to be measured, it is possible to reduce the influence of the disturbance magnetic field without arranging the magnetic sensor so that the current sensitivities of the magnetic sensors match each other. The measurement accuracy of the current flowing in the conductor to be measured can be improved while relaxing restrictions on the position and the shape of the conductor to be measured.

According to the current measurement method of claim 10, the plurality of magnetic sensors include magnetoelectric transducers having a magnetic sensitive surface, and the magnetic sensitive surface is adapted to a magnetic field generated by a current flowing through the measured conductor. It is characterized by being vertical.
As a result, it is possible to easily detect the magnetic field generated from the conductor to be measured, and to easily match the magnitude and direction of the disturbance magnetic field with respect to the plurality of magnetic sensors. For this reason, by taking the difference between the output signals from the plurality of magnetic sensors, the disturbance magnetic field can be canceled and the value of the current flowing through the conductor to be measured can be accurately measured.

According to the current measuring method of claim 11, the plurality of magnetic sensors include a magnetoelectric transducer having a magnetic sensitive surface, and the magnetic sensitive surface is adapted to a magnetic field generated by a current flowing through the conductor to be measured. And parallel.
This makes it possible to easily match the magnitude and direction of the disturbance magnetic field with respect to the plurality of magnetic sensors, and cancel the disturbance magnetic field by taking the difference between the output signals from the plurality of magnetic sensors.
The current measuring method according to claim 12 is characterized in that the conductor to be measured is a bus bar.
As a result, it is possible to measure the current flowing through the conductor to be measured while relaxing restrictions on the shape of the conductor to be measured, and to accurately measure the value of the current flowing through the conductor to be measured having a shape other than the cylinder.

According to the current measurement program of the thirteenth aspect of the present invention, the step of acquiring output signals from a plurality of magnetic sensors arranged so that the current sensitivities to the current flowing through the conductor to be measured are different from each other; And causing the computer to execute a step of calculating a value of a current flowing through the conductor to be measured based on the fetched output signal.
As a result, it is possible to reduce the influence of the disturbance magnetic field when measuring the current flowing through the conductor to be measured without arranging the magnetic sensors so that the current sensitivities of the magnetic sensors coincide with each other. The measurement accuracy of the current flowing through the conductor to be measured can be improved while reducing the size and size.

  As described above, according to the present invention, the magnetic sensors are arranged so that the current sensitivities to the currents flowing through the conductors to be measured are different from each other, and the currents flowing through the conductors to be measured based on the output signals from these magnetic sensors. By calculating the value, it is possible to reduce the influence of the disturbance magnetic field without arranging the magnetic sensors so that the current sensitivities of the magnetic sensors coincide with each other. For this reason, it becomes possible to improve the measurement accuracy of the current flowing through the conductor to be measured while relaxing restrictions on the arrangement position of the magnetic sensor and the shape of the conductor to be measured, thereby reducing the price and size of the magnetic sensor. Thus, it is possible to easily measure the current flowing through the conductor to be measured.

Hereinafter, a current measuring device and a current measuring method according to embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing a schematic configuration of a current measuring apparatus according to the first embodiment of the present invention.
In FIG. 1, two one-package magnetic sensors 2 a and 2 b are mounted on a printed circuit board 1. Here, the magnetic sensors 3a and 3b are built in the one-package magnetic sensors 2a and 2b, respectively, and the value of the current I flowing through the conductor 5 to be measured based on the output signals from the magnetic sensors 3a and 3b. The signal processing units 4a and 4b for calculating are incorporated. Examples of the conductor 5 to be measured include a bus bar, a cylindrical conductor, or a conductive wire.

In addition, as the magnetic sensors 3a and 3b, for example, magnetoelectric conversion elements such as Hall elements, MR, and ferromagnetic MR can be used, and one-package so that the magnetosensitive surfaces of these magnetoelectric conversion elements are parallel to each other. Magnetic sensors 2 a and 2 b can be arranged on the printed circuit board 1.
When measuring the value of the current I flowing through the conductor to be measured 5, the one-package magnetic sensors 2a and 2b are connected to the conductor to be measured 5 so that the magnetic sensors 3a and 3b are arranged asymmetrically with respect to the conductor to be measured 5. Install in the vicinity of.

Here, the one-package magnetic sensors 2a and 2b are mounted on the printed circuit board 1 so that the magnetic sensitive surfaces of the magnetic sensors 3a and 3b are parallel to each other. By simply placing the substrate 1 in the vicinity of the conductor to be measured 5, the directions of the magnetic sensitive surfaces of the magnetic sensors 3a and 3b with respect to the conductor to be measured 5 can be aligned with each other.
When a current I flows from the front of the conductor to be measured 5 toward the back, a magnetic field 6 is generated around the conductor to be measured 5. Then, the parts 6 a and 6 b of the magnetic field 6 generated around the conductor to be measured 5 penetrate the magnetic sensors 3 a and 3 b, respectively. The magnetic sensors 3 a and 3 b are magnetic fields generated around the conductor to be measured 5. 6 parts 6a and 6b can be sensed.

When the magnetic sensors 3a and 3b sense portions 6a and 6b of the magnetic field 6 generated around the conductor 5 to be measured, the signal processing units 4a and 4b are based on output signals from the magnetic sensors 3a and 3b. Thus, the value of the current I flowing through the conductor to be measured 5 can be calculated.
Here, the magnetic sensors 3a and 3b are arranged asymmetrically with respect to the conductor 5 to be measured, and the current sensitivity of the magnetic sensors 3a and 3b is increased by arranging the magnetic sensitive surfaces of the magnetic sensors 3a and 3b in the same direction. It is possible to make them different from each other and to match the magnitude and direction of the disturbance magnetic field with respect to these magnetic sensors 3a and 3b.

  For this reason, when calculating the value of the current I flowing through the conductor 5 to be measured, the influence of the disturbance magnetic field can be reduced, and the magnetic sensors 3a and 3b have the same current sensitivity so as to match each other. 3b is no longer required, and it is possible to improve the measurement accuracy of the current I flowing through the conductor 5 to be measured while relaxing restrictions on the positions of the magnetic sensors 3a and 3b and the shape of the conductor 5 to be measured. .

That is, the current sensitivities of the magnetic sensors 3a and 3b are Sa and Sb [V / A], respectively, and the current flowing through the conductor 5 to be measured is I [A]. In addition, the magnetic flux density of the disturbance magnetic field given from the outside to the magnetic sensors 3a and 3b is Ba and Bb [T], respectively, and the output voltages of the magnetic sensors 3a and 3b are Va and Vb [V], respectively.
Here, the current sensitivities Sa and Sb of the magnetic sensors 3 a and 3 b can be determined by the relative positions of the magnetic sensors 3 a and 3 b and the conductor to be measured 5. Then, in order to make the current sensitivities Sa and Sb of the magnetic sensors 3a and 3b with respect to the conductor to be measured 5 different from each other, the two magnetic sensors are made so that the distances between the magnetic sensors 3a and 3b and the conductor to be measured 5a are different from each other. A printed circuit board 1 on which 3a and 3b are mounted can be installed.

For example, in the example of FIG. 1, since the magnetic sensor 3a is closer to the conductor to be measured 5 than the magnetic sensor 3b, the current sensitivity Sa of the magnetic sensor 3a is higher than the current sensitivity Sb of the magnetic sensor 3b. Can be increased.
If the magnetic field sensitivities of the magnetic sensors 3a and 3b are ma and mb [V / T], the output voltages Va and Vb of the magnetic sensors 3a and 3b are given by the following equations (1) and (2), respectively. be able to.
Va = Sa × I + ma × Ba (1)
Vb = Sb × I + mb × Bb (2)

When the magnetic sensors 3a and 3b are installed in the vicinity of the conductor 5 to be measured so that the magnetic sensitive surfaces of the magnetic sensors 3a and 3b are parallel to each other, the magnetic field sensitivity of the disturbance magnetic field felt by the magnetic sensors 3a and 3b is uniform. Thus, the direction and value of the disturbance magnetic field are considered to be equal. For this reason, in the formulas (1) and (2), Ba = Bb, and the current I to be measured at this time can be expressed as follows by taking the difference between the formulas (1) and (2). It can be given by equation (3).
I = (Va−Vb−Ba (ma−mb)) / (Sa−Sb) (3)

If the characteristics of the two magnetic sensors 3a and 3b are equal to each other, it is considered that ma = mb. Therefore, the output voltages Va and Vb of the magnetic sensors 3a and 3b are expressed by the following equations (4) and (5). Can be given respectively.
Va = Sa × I + ma × Ba (4)
Vb = Sb × I + ma × Ba (5)
Then, by taking the difference between the equations (4) and (5), the magnetic flux density Ba of the disturbance magnetic field can be eliminated, and the measured current I at this time can be given by the following equation (6). it can.
I = (Va−Vb) / (Sa−Sb) (6)

Here, assuming that the current sensitivities Sb and Sa of the magnetic sensors 3a and 3b are known, the current I flowing through the measured conductor 5 can be easily calculated by using the output voltages Va and Vb of the magnetic sensors 3a and 3b. can do. The current sensitivities Sb and Sa of the magnetic sensors 3a and 3b are simulated according to the size, such as the outer shape, cross-sectional shape, and length of the conductor 5 to be measured, and the distance between the magnetic sensors 3a and 3b and the conductor 5 to be measured. It can be easily calculated by calculating with The magnetic field sensitivities ma and mb of the magnetic sensors 3a and 3b are voltage values output when a reference magnetic field is applied, and are predetermined because they are unique to the magnetic sensors 3a and 3b.
For this reason, when measuring the value of the current I flowing through the conductor to be measured 5, the printed circuit board 1 may be installed so that the distance between the magnetic sensors 3a and 3b and the conductor to be measured 5a is different from each other, and the magnetic sensors 3a and 3b. It is possible to perform highly accurate current measurement while improving the degree of freedom regarding the mounting position.

Further, the difference (Sa−Sb) between the current sensitivities Sb and Sa of the magnetic sensors 3a and 3b can be calculated by calibration. That is, a current having a known current value I0 is passed through the conductor 5 to be measured, and the output voltages Va0 and Vb0 of the magnetic sensors 3a and 3b at this time are measured. When the output voltages Va0 and Vb0 of the magnetic sensors 3a and 3b when the current of the current value I0 is passed are obtained, the difference between the current sensitivities Sb and Sa of the magnetic sensors 3a and 3b is obtained by using the equation (6). Sa-Sb) can be given by the following equation (7).
(Sa−Sb) = (Va0−Vb0) / I0 (7)
Thus, by previously obtaining the difference (Sa-Sb) between the current sensitivities Sb and Sa of the magnetic sensors 3a and 3b, there is no need to obtain the individual current sensitivities Sb and Sa of the magnetic sensors 3a and 3b. The measured current I can be obtained simply by measuring the output voltages Va and Vb of the sensors 3a and 3b.

  The conductor to be measured 5 is not particularly limited, and may be a rectangular parallelepiped, cylindrical, linear, rectangular, or edge-lined conductor in addition to a bus bar. The magnetic sensors 3a and 3b are not particularly limited as long as they are magnetic sensors such as magnetoelectric transducers that detect the magnetic field 6. Here, the magnetoelectric conversion element is preferably a magnetoresistive element or a Hall element, and the magnetic sensors 3a and 3b using the Hall element are those that receive the magnetic field 6 directly perpendicular to the magnetic sensitive surface, or a magnetic convergence plate. It is preferable to receive the magnetic field by bending it perpendicularly to the magnetosensitive surface. In particular, as the magnetoelectric conversion element, in addition to a monolithic Si Hall element, use of a high sensitivity Hall element such as InSb, GaAs, or InAs is preferable. Further, in order to make the current sensitivities of the magnetic sensors 3a and 3b different from each other, in addition to the method of making the distances between the magnetic sensors 3a and 3b and the measured conductor 5 different from each other, the magnetic sensors 3a and 3b and the measured conductor 5 , The magnetic sensitivity of the magnetic sensors 3a and 3b themselves may be changed, and the current sensitivity may be changed.

FIG. 2 is a block diagram showing a schematic configuration of a current measuring apparatus according to the second embodiment of the present invention.
In FIG. 2, a one-package magnetic sensor 11 includes a magnetic sensor unit 12a and a signal processing unit 12b.
Here, the magnetic sensor unit 12a is provided with a plurality of magnetic sensors 14a and 14b and bias circuits 13a and 13b for driving the magnetic sensors 14a and 14b, respectively. As the magnetic sensors 14a and 14b, for example, magnetoelectric conversion elements such as Hall elements can be used, and the magnetosensitive surfaces of these magnetoelectric conversion elements can be arranged in parallel to each other.

  The signal processing unit 12b is provided with amplification circuits 15a and 15b for amplifying output signals from the magnetic sensors 14a and 14b, respectively, and magnetic field sensitivities ma and mb and current sensitivities Sb and Sa of the magnetic sensors 14a and 14b. Furthermore, a storage circuit 17 is provided for storing a current value I0 at the time of calibration. Further, the signal processing unit 12b includes an arithmetic processing circuit 16 for calculating the value of the current flowing through the conductor to be measured based on the amplified values output from the amplifier circuits 15a and 15b and the value stored in the storage circuit 17, and the arithmetic processing circuit 16 An output circuit 18 is provided for outputting the value calculated by the processing circuit 16 to the outside.

When measuring the value of the current flowing through the conductor to be measured, the one package magnetic sensor 11 is installed in the vicinity of the conductor to be measured so that the magnetic sensors 14a and 14b are arranged asymmetrically with respect to the conductor to be measured.
When magnetic fields generated around the conductor to be measured are detected by the magnetic sensors 14a and 14b, output signals from the magnetic sensors 14a and 14b are amplified by the amplifier circuits 15a and 15b, respectively.

The signals amplified by the amplifier circuits 15a and 15b are respectively input to the arithmetic processing circuit 16, and the arithmetic processing circuit 16 is based on the values of the current sensitivities Sb and Sa stored in the storage circuit 17 and measured. The value of the current flowing through the conductor is calculated. The value of the current flowing through the conductor to be measured is buffered by the output circuit 18 and can be output to the outside.
At the time of calibration, the arithmetic processing circuit 16 reads the current value I0 stored in the storage circuit 17, and outputs the output signal from each of the magnetic sensors 14a and 14b when the current of the current value I0 flows through the conductor to be measured. Based on this, the difference (Sa−Sb) between the current sensitivities Sb and Sa of the magnetic sensors 14a and 14b can be calculated. Then, the arithmetic processing circuit 16 may obtain the value of the current flowing through the conductor to be measured by using the difference (Sa−Sb) between the current sensitivities Sb and Sa of the magnetic sensors 14a and 14b.

Alternatively, the storage circuit 17 may store a difference (Sa−Sb) between the current sensitivities Sb and Sa at the time of calibration and output the value to the arithmetic processing circuit 11 at the time of current measurement.
As a result, the plurality of magnetic sensors 14a, 14b and the signal processing unit 12b can be packaged, and the measurement accuracy of the current flowing through the conductor to be measured can be improved. It is possible to easily measure the current flowing through the conductor to be measured while reducing the cost and size.

FIG. 3 is a perspective view illustrating a schematic configuration of a current measuring device according to the third embodiment of the present invention.
In FIG. 3, the one-package current sensor 21 is provided with two magnetic sensors 23 a and 23 b and a signal processing circuit 24. As the magnetic sensors 23a and 23b, Hall elements, magnetoresistive elements, coils, and the like can be used. The magnetic sensors 23a and 23b and the signal processing circuit 24 are mounted on the lead frame 22, and the magnetic sensors 23a and 23b and the signal processing circuit 24 are connected to the lead pin 22 '.

  Here, when the magnetic sensors 23a and 23b are mounted on the lead frame 22, the magnetic sensors 23a and 23b can be arranged so that the magnetic sensitive surfaces thereof are parallel to each other. The lead frame 22 on which the magnetic sensors 23 a and 23 b and the signal processing circuit 24 are mounted is sealed with a sealing material 25. As the sealing material 25, a sealing resin such as epoxy can be used.

As a result, it is possible to make the plurality of magnetic sensors 23a and 23b and the signal processing circuit 24 into one package while suppressing complication of the manufacturing process, and reducing the cost and size of the one-package magnetic sensor 21. Thus, it is possible to easily measure the current flowing through the conductor to be measured.
The magnetic sensors 23a and 23b may be magnetic sensors such as a Hall element that can detect a magnetic field perpendicular to the package surface, or the Hall element is set up perpendicular to the package surface, or a magnetic converging plate is used. A magnetic field horizontal to the package surface may be detected. In either case, the mounting direction on the lead frame 22 may be selected as appropriate.

FIG. 4 is a perspective view illustrating a schematic configuration of a current measuring device according to the fourth embodiment of the present invention.
In FIG. 4, the one-package current sensor 31a is provided with a magnetic sensor 33a and a signal processing circuit 34a, and the one-package current sensor 31b is provided with a magnetic sensor 33b and a signal processing circuit 34b. As the magnetic sensors 33a and 33b, Hall elements, magnetoresistive elements, coils and the like can be used.

The magnetic sensor 33a and the signal processing circuit 34a are mounted on the lead frame 32a, and the magnetic sensor 33a and the signal processing circuit 34a are connected to the lead pin 32a ′. The lead frame 32a on which the magnetic sensor 33a and the signal processing circuit 34a are mounted is sealed with a sealing material 35a.
The magnetic sensor 33b and the signal processing circuit 34b are mounted on the lead frame 32b, and the magnetic sensor 33b and the signal processing circuit 34b are connected to the lead pin 32b ′. The lead frame 32b on which the magnetic sensor 33b and the signal processing circuit 34b are mounted is sealed with a sealing material 35b.

  When measuring the current flowing through the conductor under measurement, the one package current sensors 31a and 31b are arranged so that the magnetic sensitive surfaces of the magnetic sensors 33a and 33b are parallel to each other, so that the current flowing through the conductor under measurement is measured. Measurement can be performed, and the measurement accuracy of the current flowing through the conductor to be measured can be improved while relaxing restrictions on the arrangement positions of the one-package current sensors 31a and 31b.

  The magnetic sensors 33a and 33b may be magnetic sensors such as a Hall element that can detect a magnetic field perpendicular to the package surface, or the Hall element is set up perpendicular to the package surface, or a magnetic converging plate is used. A magnetic field horizontal to the package surface may be detected. In either case, the mounting direction on the lead frames 32a and 32b may be selected as appropriate.

FIG. 5 is a cross-sectional view for explaining a current measuring method according to the fifth embodiment of the present invention. In the fifth embodiment shown in FIG. 5, attention is paid to the positional relationship between the conductor 41 to be measured and the magnetic sensors 42a and 42b, and the printed circuit board on which the magnetic sensors 42a and 42b are mounted is omitted.
In FIG. 5, a plurality of magnetic sensors 42 a and 42 b are arranged on the conductor 41 to be measured so that the magnetosensitive surfaces are parallel to each other. Here, the distance between the left and right magnetic sensors 42a and 42b and the conductor 41 to be measured is different. That is, since the magnetic sensor 42a is closer to the measured conductor 41 than the magnetic sensor 42b, the current sensitivity of the magnetic sensor 42a can be made larger than the current sensitivity of the magnetic sensor 42b. When the difference between the distances is increased, the sensitivity difference between the magnetic sensors 42a and 42b can be increased, and the measurement accuracy of the current flowing through the conductor to be measured 41 can be improved.

  Here, when the magnetic sensors 42a and 42b are arranged, it is only necessary that the current sensitivities of the magnetic sensors 42a and 42b with respect to the conductor 41 to be measured are different. Even if the polarities of the outputs of the magnetic sensors 42a and 42b are the same, It doesn't matter if they are opposite to each other. Further, by arranging the magnetic sensors 42a and 42b on the same plane, the magnetic sensors 42a and 42b can be mounted on the same plane of the printed circuit board or the lead frame having the same thickness, and the mounting of the magnetic sensors 42a and 42b. Can be facilitated.

FIG. 6 is a cross-sectional view showing a schematic configuration of a current measuring apparatus according to the sixth embodiment of the present invention. The sixth embodiment corresponds to an example of the fifth embodiment in FIG.
In FIG. 6, the magnetic sensor 56a is provided with a hall element 54a standing vertically on the substrate 53a so as to detect a magnetic field parallel to the substrate surface, and the hall element 54a is sealed with a sealing material 55a. ing. The magnetic sensor 56 a provided with the Hall element 54 a is mounted on the printed circuit board 52, and the printed circuit board 52 mounted with the magnetic sensor 56 a is disposed on the bus bar 51.

  In addition, the magnetic sensor 56b is provided with a hall element 54b standing vertically on the substrate 53b, and the hall element 54b is sealed with a sealing material 55b. The magnetic sensor 56b provided with the Hall element 54b is disposed beside the magnetic sensor 56a so that the magnetic sensitive surfaces of the Hall elements 54a and 54b are parallel to each other. Here, the magnetic sensor 56b can be disposed at an arbitrary position within a range where current sensitivity can be obtained as long as the magnetic sensitive surfaces of the Hall elements 54a and 54b are parallel to each other.

  Accordingly, it is possible to efficiently detect the magnetic field generated due to the current flowing through the bus bar 51 and measure the current flowing through the bus bar 51 based on the difference in current sensitivity between the Hall elements 54a and 54b. It becomes possible to cancel the influence of the disturbance magnetic field. For this reason, it becomes possible to improve the measurement accuracy of the current flowing through the bus bar 51 while relaxing restrictions on the arrangement positions of the magnetic sensors 56a and 56b and the shape of the bus bar 51.

FIG. 7 is a sectional view showing a schematic configuration of a current measuring apparatus according to the seventh embodiment of the present invention. The seventh embodiment corresponds to an example of the fifth embodiment in FIG.
In FIG. 7, the magnetic sensor 66 is provided with Hall elements 64a and 64b that are vertically set on the substrates 63a and 63b, respectively, and a signal processing circuit 63c so as to detect a magnetic field parallel to the substrate surface. The Hall elements 64 a and 64 b and the signal processing circuit 63 c are sealed with a sealing material 65. The magnetic sensor 66 provided with the Hall elements 64 a and 64 b and the signal processing circuit 63 c is mounted on the printed circuit board 62, and the printed circuit board 62 mounted with the magnetic sensor 66 is installed on the bus bar 61. Here, when the printed circuit board 62 on which the magnetic sensor 66 is mounted is installed on the bus bar 61, the bus bar 61 is arranged immediately below the hall element 64 a and the hall element 64 b is arranged outside the bus bar 61. be able to.

  Thus, it is possible to efficiently detect the magnetic field generated due to the current flowing through the bus bar 61, and to measure the current flowing through the bus bar 61 based on the difference in current sensitivity between the Hall elements 64a and 64b. In addition, it is possible to cancel the influence of the disturbance magnetic field by simply installing the printed circuit board 62 on which the magnetic sensor 66 is mounted on the bus bar 61. Therefore, it is possible to improve the measurement accuracy of the current flowing through the bus bar 61 while relaxing the restrictions on the arrangement position of the magnetic sensor 66 and the shape of the bus bar 61, and easily measure the accuracy of the current flowing through the bus bar 61. Can be done.

FIG. 8 is a cross-sectional view for explaining a current measuring method according to the eighth embodiment of the present invention. In the eighth embodiment shown in FIG. 8, attention is paid to the positional relationship between the conductor to be measured 71 and the magnetic sensors 72a and 72b, and the printed circuit board on which the magnetic sensors 72a and 72b are mounted is omitted.
In FIG. 8, a plurality of magnetic sensors 72a and 72b are arranged on the conductor to be measured 71 so that the magnetic sensitive surfaces are parallel to each other. Here, the projection of one magnetic sensor 72a onto the conductor to be measured 71 can be the same as the projection of the other magnetic sensor 72b onto the conductor under measurement 71.

  As a result, the distance from the conductor 71 to be measured to the magnetic sensors 72a and 72b can be made different from each other, and the influence of the disturbance magnetic field can be canceled, while the current sensitivity of the magnetic sensors 72a and 72b is based on the difference. Thus, the current flowing through the conductor to be measured 71 can be measured, and the assembly of the magnetic sensors 72a and 72b can be facilitated. For this reason, it is possible to improve the measurement accuracy of the current flowing through the conductor to be measured 71, and to reduce the price and size of the magnetic sensors 72a and 72b.

FIG. 9 is a cross-sectional view showing a schematic configuration of a current measuring apparatus according to the ninth embodiment of the present invention. The ninth embodiment corresponds to an example of the eighth embodiment in FIG.
In FIG. 9, the magnetic sensor 86 is provided with Hall elements 84 a and 84 b mounted on the substrate 83 so as to detect a magnetic field perpendicular to the substrate surface, and the Hall elements 84 a and 84 b are sealed with a sealing material 85. It has been stopped. The magnetic sensor 86 is mounted on the printed circuit board 82 in a vertically standing state, and the printed circuit board 82 mounted with the magnetic sensor 86 is installed on the bus bar 81.

  Here, the current sensitivity of the Hall elements 84a and 84b can be determined by the distance between the conductor 81 to be measured and the Hall elements 84a and 84b. Therefore, the current flowing through the bus bar 81 can be measured based on the difference in current sensitivity between the Hall elements 84a and 84b by making the distance between the conductor 81 to be measured different from the Hall elements 84a and 84b. Further, by mounting the Hall elements 84a and 84b on the same substrate 83, the magnetic sensitive surfaces of the Hall elements 84a and 84b can be made parallel to each other, and the magnetic sensitive surfaces of the Hall elements 84a and 84b can be To face the same direction.

  Further, by mounting the magnetic sensor 86 on the printed circuit board 82 in a vertically standing state, the magnetic field generated by the current flowing through the bus bar 81 can be efficiently penetrated through the magnetic sensitive surfaces of the Hall elements 84a and 84b. it can. In addition, by using the magnetic sensor 86 in which the plurality of Hall elements 84a and 84b are integrally molded, the magnetic sensor 86 is simply installed on the bus bar 81, so that the magnetic sensitive surfaces of the Hall elements 84a and 84b are parallel to each other. Can be maintained stably.

  Therefore, the current flowing through the bus bar 81 can be measured based on the difference in current sensitivity between the Hall elements 84a and 84b while allowing the magnetic field generated due to the current flowing through the bus bar 81 to be detected efficiently. In addition, it is possible to cancel the influence of the disturbance magnetic field by simply installing the printed circuit board 82 on which the magnetic sensor 86 is mounted on the bus bar 81. As a result, it is possible to improve the measurement accuracy of the current flowing through the bus bar 81 while relaxing the restrictions on the arrangement position of the magnetic sensor 86 and the shape of the bus bar 81, and easily measure the accuracy of the current flowing through the bus bar 81. Can be done.

FIG. 10 is a cross-sectional view for explaining a current measuring method according to the tenth embodiment of the present invention. In the tenth embodiment of FIG. 10, attention is paid to the positional relationship between the conductor 91 to be measured and the magnetic sensors 92a and 92b, and the printed circuit board on which the magnetic sensors 92a and 92b are mounted is omitted.
In FIG. 10, a plurality of magnetic sensors 92a and 92b are arranged on the conductor 91 to be measured so that the magnetic sensitive surfaces are parallel to each other. Here, one magnetic sensor 92b of the plurality of magnetic sensors 92a and 92b is arranged far from the measured conductor 91, and the current sensitivity of the magnetic sensor 92a arranged close to the measured conductor 91 is mainly used. Thus, the current can be measured. That is, the current sensitivity of the magnetic sensor 92b is negligibly small, and the magnetic sensor 92b can be used as a reference only for canceling the disturbance magnetic field.
As a result, it is possible to increase the degree of freedom regarding the mounting position of the magnetic sensor 92b while suppressing the deterioration of the current measurement accuracy due to the influence of the disturbance magnetic field.

FIG. 11 is a sectional view showing a schematic configuration of a current measuring device according to the eleventh embodiment of the present invention. The eleventh embodiment corresponds to an example of the tenth embodiment of FIG.
In FIG. 11, the magnetic sensor 106 is provided with Hall elements 104a and 104b mounted on substrates 103a and 103b, respectively, so as to detect a magnetic field parallel to the substrate surface. The substrate 103b on which the Hall element 104b is mounted is disposed on the substrate 103a on which the Hall element 104a is mounted, and a step is formed between the substrates 103a and 103b. The Hall elements 104a and 104b are sealed with a sealing material 105. The magnetic sensor 106 provided with the Hall elements 104 a and 104 b is mounted on the printed circuit board 102, and the printed circuit board 102 mounted with the magnetic sensor 106 is installed on the bus bar 101.

Here, by placing the substrate 103b on which the Hall element 104b is mounted on the substrate 103a on which the Hall element 104a is mounted, simply placing the printed board 102 on which the magnetic sensor 106 is mounted on the bus bar 101, The distances from the bus bar 101 to the Hall elements 104a and 104b can be made different from each other while keeping the magnetic sensitive surfaces of the Hall elements 104a and 104b parallel to each other. Therefore, it becomes possible to measure the current flowing through the conductor to be measured 71 based on the difference in current sensitivity between the magnetic sensors 72a and 72b while making it possible to cancel the influence of the disturbance magnetic field, and the current flowing through the bus bar 61 can be measured. Measurement accuracy can be improved.
Further, by using a specially formed substrate, it is possible to mold the mounting positions of the Hall elements 104a and 104b with a step, and the magnetic sensor 106 can be easily assembled.

FIG. 12 is a cross-sectional view for explaining a current measuring method according to the twelfth embodiment of the present invention. In the twelfth embodiment of FIG. 12, attention is paid to the positional relationship between the conductor 111 to be measured and the magnetic sensors 112a and 112b, and the printed circuit board on which the magnetic sensors 112a and 112b are mounted is omitted.
In FIG. 12, a plurality of magnetic sensors 112a and 112b are arranged on the conductor to be measured 111 so that the magnetic sensitive surfaces are parallel to each other. Here, the conductor to be measured 111 is sandwiched between the magnetic sensors 112a and 112b, and the magnetic sensors 112a and 112b can be arranged so that the distances from the conductor to be measured 111 to the magnetic sensors 112a and 112b are different from each other. .

  As a result, it is possible to measure the current flowing through the conductor to be measured 111 based on the difference in current sensitivity between the magnetic sensors 112a and 112b, while allowing the influence of the disturbance magnetic field to be canceled, and to flow through the conductor to be measured 111. The current measurement accuracy can be improved, and the degree of freedom of arrangement of the magnetic sensors 112a and 112b can be improved.

FIG. 13: is sectional drawing which shows schematic structure of the electric current measurement apparatus which concerns on 13th Embodiment of this invention. The thirteenth embodiment corresponds to an example of the twelfth embodiment of FIG.
In FIG. 13, the magnetic sensor 126a is provided with a hall element 124a standing vertically on the substrate 123a, and the hall element 124a is sealed with a sealing material 125a. The magnetic sensor 126a provided with the hall element 124a is mounted on the printed circuit board 122a.

In addition, the magnetic sensor 126b is provided with a hall element 124b that stands vertically on the substrate 123b, and the hall element 124b is sealed with a sealing material 125b. The magnetic sensor 126b provided with the hall element 124b is mounted on the printed circuit board 122b.
The printed circuit boards 122a and 122b provided with the magnetic sensors 126a and 126b are arranged above and below the bus bar 121 so as to sandwich the bus bar 121 therebetween. SHAPE ** MERGEFORMAT Here, the magnetic sensors 126a and 126b can be arranged at arbitrary positions within a range where current sensitivity can be obtained as long as the magnetic sensitive surfaces of the Hall elements 124a and 124b are parallel to each other.

  Thus, it is possible to efficiently detect the magnetic field generated due to the current flowing through the bus bar 121, and measure the current flowing through the bus bar 121 based on the difference in current sensitivity between the Hall elements 124a and 124b. It becomes possible to cancel the influence of the disturbance magnetic field. Therefore, it is possible to improve the measurement accuracy of the current flowing through the bus bar 121 while relaxing restrictions on the arrangement positions of the magnetic sensors 126a and 126b and the shape of the bus bar 121.

FIG. 14 is a cross-sectional view for explaining a current measuring method according to the fourteenth embodiment of the present invention. In the fourteenth embodiment shown in FIG. 14, attention is paid to the positional relationship between the conductor to be measured 131 and the magnetic sensors 132a and 132b, and the printed circuit board on which the magnetic sensors 132a and 132b are mounted is omitted.
In FIG. 14, a plurality of magnetic sensors 132a and 132b are arranged on a columnar conductor 131 so that the magnetic sensitive surfaces are parallel to each other. Here, the magnetic sensors 132a and 132b can be arranged so that the distances from the cylindrical conductor 131 to the magnetic sensors 132a and 132b are different from each other.

  This makes it possible to measure the current flowing through the cylindrical conductor 131 based on the difference in current sensitivity between the magnetic sensors 132a and 132b while allowing the influence of the disturbance magnetic field to be canceled, and flows into the cylindrical conductor 131. It becomes possible to improve the current measurement accuracy, and also to improve the degree of freedom of arrangement of the magnetic sensors 132a and 132b when measuring the current flowing through the cylindrical conductor 131.

FIG. 15 is a sectional view showing a schematic configuration of a current measuring apparatus according to the fifteenth embodiment of the present invention.
In FIG. 15, a signal processing circuit 142 is mounted on a substrate 141, and magnetic converging plates 144a and 144b are arranged on the signal processing circuit 142 at a predetermined interval from each other. Here, the Hall elements 104a and 104b are embedded in the surface layer of the signal processing circuit 142, the end of the magnetic focusing plate 144a is disposed on the Hall element 143a, and the end of the magnetic focusing plate 144b is positioned on the Hall element 143b. Can be arranged. The signal processing circuit 142, the Hall elements 143a and 143b, and the magnetic focusing plates 144a and 144b are sealed with a sealing material 145. The magnetic flux converging plates 144a and 144b can be made of a high magnetic permeability and soft magnetic material.

  If the magnetic resistances of the Hall elements 143a and 143b are smaller than the magnetic resistance of the signal processing circuit 142, the magnetic field horizontally incident on the magnetic converging plate 144a travels horizontally in the magnetic converging plate 144a. The magnetic field that has traveled in the magnetic converging plate 144a is bent at the position of the Hall element 143a and penetrates the Hall element 143a vertically. The magnetic field penetrating the hall element 143a is bent in the direction of the hall element 143b and vertically penetrates the hall element 143b. The magnetic field penetrating through the Hall element 143b is bent at the position of the magnetic convergence plate 144a and travels horizontally in the magnetic convergence plate 144a.

As a result, even when the magnetic sensitive surfaces of the Hall elements 143a and 143b are arranged in parallel to the magnetic field generated from the conductor to be measured, the magnetic field generated from the conductor to be measured can be efficiently detected. While making it possible to arrange the magnetic sensor horizontally on the conductor, it is possible to accurately measure the current flowing through the conductor to be measured.
As described above, according to the above-described embodiment, in the current measuring apparatus or method in which the magnetic sensor is disposed close to the wide and thick rectangular or thin plate-like measured conductor (for example, bus bar), two By arranging the above same magnetic sensors so as to be parallel to each other, even if the magnetic sensitivities of the two magnetic sensors with respect to magnetism such as disturbance are the same, the current sensitivities can be made different. For this reason, the current flowing through the conductor to be measured can be accurately measured while canceling the disturbance magnetic field by taking the difference between the output signals.

In this case, since the installation condition of the magnetic sensor is only that the magnetic sensitive surface of the magnetic sensor is parallel, the degree of freedom regarding the mounting position of the magnetic sensor can be expanded.
In addition, since magnetic sensors with the same characteristics need only be placed in parallel with the conductor to be measured, it is extremely small by being attached to a substrate such as the same printed circuit board or integrally formed on the same lead frame or the same substrate. A simple current sensor measuring device can be configured.

Further, if the positional relationship of the conductor to be measured is known, the two current sensitivities can be accurately calculated by calculation, so that sufficiently practical current measurement can be performed.
Further, the current sensitivity can be varied and adjusted in a wide range depending on the arrangement relationship between the two magnetic sensors, and the current sensitivity can be adjusted. Even if the current sensitivity is not strictly defined, if calibration is performed by passing a defined current, the current sensitivity can be obtained accurately, and therefore, a more accurate measurement is possible.

  In addition, since it is only necessary to arrange the magnetic sensitive surfaces of the magnetic sensors so as to be parallel to each other, the magnetic sensors such as Hall elements, MR elements, and coils are mounted on the printed circuit board surface so that the magnetic sensitive surfaces of the magnetic sensors are parallel. A state can be easily created, and a component placement design with a very high degree of freedom can be performed. Further, even when a magnetic sensor must be installed on the back surface of the conductor to be measured due to restrictions on component arrangement, the current measuring device can be configured on the same plane or in the same package.

  In the current measuring device of the present invention, the magnitude of the current flowing through the conductor to be measured can be measured using a magnetic sensor, and for example, it can be used for various applications such as monitoring the power consumption of home appliances.

It is a perspective view showing a schematic structure of a current measuring device concerning a 1st embodiment of the present invention. It is a block diagram which shows schematic structure of the electric current measurement apparatus which concerns on 2nd Embodiment of this invention. It is a perspective view seeing through and showing the schematic structure of the current measuring device concerning a 3rd embodiment of the present invention. It is a perspective view seeing through and showing the schematic structure of the current measuring device concerning a 4th embodiment of the present invention. It is sectional drawing for demonstrating the electric current measurement method which concerns on 5th Embodiment of this invention. It is sectional drawing which shows schematic structure of the electric current measurement apparatus which concerns on 6th Embodiment of this invention. It is sectional drawing which shows schematic structure of the electric current measuring apparatus which concerns on 7th Embodiment of this invention. It is sectional drawing for demonstrating the electric current measurement method which concerns on 8th Embodiment of this invention. It is sectional drawing which shows schematic structure of the electric current measuring apparatus which concerns on 9th Embodiment of this invention. It is sectional drawing for demonstrating the electric current measurement method which concerns on 10th Embodiment of this invention. It is sectional drawing which shows schematic structure of the electric current measurement apparatus which concerns on 11th Embodiment of this invention. It is sectional drawing for demonstrating the electric current measurement method which concerns on 12th Embodiment of this invention. It is sectional drawing which shows schematic structure of the electric current measurement apparatus which concerns on 13th Embodiment of this invention. It is sectional drawing for demonstrating the electric current measurement method which concerns on 14th Embodiment of this invention. It is sectional drawing which shows schematic structure of the electric current measuring apparatus which concerns on 15th Embodiment of this invention.

Explanation of symbols

1 Printed circuit board 2a, 2b, 11, 21, 31a, 31b One package current sensor 3a, 3b, 14a, 14b, 23a, 23b, 33a, 33b, 42a, 42b, 56a, 56b, 66, 72a, 72b, 86, 92 a, 92 b, 106, 112 a, 112 b, 126 a, 126 b, 132 a, 132 b Magnetic sensor 4 a, 4 b Signal processing unit 5, 41, 71, 91, 111 Measured conductor 6 Magnetic field generated by current flowing through the measured conductor 6 a, 6 b Part of the magnetic field generated by the current flowing through the conductor to be measured 12a Magnetic sensor unit 12b, 24, 34a, 34b, 63c, 142 Signal processing circuit 13a, 13b Bias circuit 15a, 15b Amplifying circuit 16 Arithmetic processing circuit 17 Storage circuit 18 Output circuit 22, 32a, 32b Lead frame 22 ', 32a', 32b ′ Lead pin 51, 61, 81, 101, 121 Bus bar 54a, 54b, 64a, 64b, 84a, 84b, 104a, 104b, 124a, 124b, 143a, 143b Hall element 8, 52, 62, 82, 102, 122a, 122b Printed circuit board 25, 35a, 35b, 55a, 55b, 65, 85, 105, 125a, 125b, 145 Sealant 53a, 53b, 63a, 63b, 83, 103a, 103b, 123a, 123b, 141 Substrate 131 Columnar conductor 144a, 144b Magnetic converging plate

Claims (13)

A plurality of magnetic sensors;
And a signal processing unit configured to calculate a value of a current flowing through the conductor to be measured based on an output signal reflecting a difference in current sensitivity of the magnetic sensor.   The current measuring apparatus according to claim 1, wherein the magnetic sensor includes magnetoelectric transducers having magnetic sensitive surfaces arranged in parallel to each other.   The current measuring device according to claim 2, wherein the magnetic field sensitivities of the plurality of magnetic sensors are equal to each other.   The current measuring device according to claim 3, further comprising a base material on which the plurality of magnetic sensors are mounted so that the magnetic sensitive surfaces are parallel to each other. The magnetic sensor is
A Hall element;
Magnetic convergence arranged parallel to the magnetic sensing surface of the Hall element, converges the magnetic field generated by the current flowing through the conductor to be measured, and guides the vertical component of the converged magnetic field to the magnetic sensing surface of the Hall element A current measuring device according to claim 1, further comprising a plate. The signal processing means includes
Based on the magnetic field sensitivity of two magnetic sensors of the plurality of magnetic sensors, the current sensitivity of the two magnetic sensors, and the value of the output signal of the two magnetic sensors, the value of the current flowing through the conductor to be measured is calculated. The current measuring device according to claim 1, wherein the current measuring device is calculated. When the current sensitivities of the two magnetic sensors are Sa and Sb [V / A], respectively, and the values of the output signals of the two magnetic sensors are Va and Vb [V], respectively.
The value I [A] of the current flowing through the measured conductor is
I = (Va−Vb) / (Sa−Sb)
The current measurement device according to claim 3, wherein the current measurement device is a current measurement device. The signal processing means includes
Calibration for preliminarily calculating a difference (Sa−Sb) in current sensitivity between the two magnetic sensors based on a known current value flowing through the conductor to be measured and the output signal values of the two magnetic sensors at that time. The current measuring device according to claim 7, further comprising a measuring means. Arranging a plurality of magnetic sensors so that current sensitivities to currents flowing through the conductor to be measured are different from each other;
Capturing an output signal from the magnetic sensor;
Calculating a value of a current flowing through the conductor to be measured based on output signals taken from the plurality of magnetic sensors.   10. The magnetic sensor according to claim 9, wherein each of the plurality of magnetic sensors includes a magnetoelectric conversion element having a magnetosensitive surface, and the magnetosensitive surface is perpendicular to a magnetic field generated by a current flowing through the conductor to be measured. Current measurement method.   10. The magnetic sensor according to claim 9, wherein each of the plurality of magnetic sensors includes a magnetoelectric conversion element having a magnetosensitive surface, and the magnetosensitive surface is parallel to a magnetic field generated by a current flowing through the conductor to be measured. Current measurement method.   The current measuring method according to claim 9, wherein the conductor to be measured is a bus bar. Capturing output signals from a plurality of magnetic sensors arranged to have different current sensitivities to the current flowing through the conductor to be measured;
A computer program for causing a computer to execute a step of calculating a value of a current flowing through the conductor to be measured based on output signals taken from the plurality of magnetic sensors.

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