Current detection device

Abstract

To provide a current detector capable of accurately detecting a current value with a simple configuration.SOLUTION: A current detector includes: a first electrode portion 10 having conductivity; a second electrode portion 20 having conductivity; a Hall effect generation portion 30 that is provided between the first electrode portion and the second electrode portion, generates a magnetic field around the Hall effect generation portion, and generates electromotive force inside the Hall effect generation portion by a Hall effect generated when a current flows to a direction from the first electrode portion to the second electrode portion; and a calculation portion 60 that is connected to the Hall effect generation portion, detects the electromotive force generated by the Hall effect generation portion, and detects the magnitude of the current flowing between the first electrode portion and the second electrode portion on the basis of the detected electromotive force.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a current detection device.

Background Art

[0002] Conventionally, a current detection device using a shunt resistor including two electrode portions, a resistor disposed between the two electrode portions, and voltage detection terminals provided on each of the two electrode portions has been known (see, for example, Patent Document 1). In this shunt resistor, each of the electrode portion and the resistor is composed of a different member.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The current detection device described in Patent Document 1 detects the potential difference between the voltage detection terminals provided on the two electrode portions, and calculates the voltage drop due to the resistor using Ohm's law, thereby detecting the value of the current flowing through the shunt resistor.

[0005] By the way, in a shunt resistor configured by combining an electrode portion and a resistor, when current flows, the electrode portion and the resistor generate heat, and the resistance values of these electrode portion and resistor may change. However, since the current detection device described in Patent Document 1 detects the value of the current flowing through the shunt resistor using Ohm's law, the change in the resistance value due to the temperature change of the electrode portion and the resistor becomes a factor causing an error in the current value detected by the current detection device. On the other hand, in a current detection device using a shunt resistor, there is a method for correcting the error in the current value due to the temperature change of the electrode portion and the resistor.

[0006] However, when the electrodes and resistor of a shunt resistor are made of different materials, their temperature characteristics—the ratio of the change in resistance to the change in temperature—will differ. Therefore, when correcting errors in the current value, it is necessary to consider the temperature characteristics of both the electrodes and the resistor.

[0007] In contrast, the current detection device described in Patent Document 1 includes a temperature compensation circuit having three temperature sensors that detect the temperature of each of the two electrode parts and the resistor, and corrects the current value detected by the temperature compensation circuit. However, it is undesirable to include a temperature compensation circuit with multiple temperature sensors in this way because it increases the number of components in the current detection device.

[0008] The purpose of this disclosure is to provide a current detection device that can accurately detect current values ​​with a simple configuration. [Means for solving the problem]

[0009] The invention described in claim 1 is, A current detection device, A first electrode portion (10) having conductivity, A second electrode portion (20) having conductivity, A Hall effect generating unit (30) is provided between the first electrode portion and the second electrode portion, is magnetized itself, and generates an electromotive force within itself due to the Hall effect that occurs when current flows in the direction from the first electrode portion to the second electrode portion, The system includes a calculation unit (60) connected to a Hall effect generating unit, which detects the electromotive force generated by the Hall effect generating unit and, based on the detected electromotive force, detects the magnitude of the current flowing between the first electrode unit and the second electrode unit. 、 The Hall effect generating section is composed of a magnetic material that has spontaneous magnetization and maintains the direction of spontaneous magnetization even without being affected by an external magnetic field, and is set so that the magnitude of its own magnetization is smaller than the magnitude of the magnetic field strength at which it saturates. ru. Furthermore, the invention described in claim 6 is, A current detection device, A first electrode portion (10) having conductivity, A second electrode portion (20) having conductivity, A Hall effect generating unit (30) is provided between the first electrode portion and the second electrode portion, is magnetized itself, and generates an electromotive force within itself due to the Hall effect that occurs when current flows in the direction from the first electrode portion to the second electrode portion, It includes a calculation unit (60) connected to a Hall effect generating unit, which detects the electromotive force generated by the Hall effect generating unit and detects the magnitude of the current flowing between the first electrode unit and the second electrode unit based on the detected electromotive force, The Hall effect generating unit includes a magnet (31) that generates a magnetic field and a magnetic material (32) that is magnetized by the influence of the magnetic field generated by the magnet. Magnetic materials maintain their magnetization direction due to the influence of the magnetic field generated by a magnet. A magnet generates a magnetic field strength that is less than the magnetic field strength required for a magnetic material to reach saturation magnetization. Furthermore, the invention described in claim 11 is, A current detection device, A first electrode portion (10) having conductivity, A second electrode portion (20) having conductivity, A Hall effect generating unit (30) is provided between the first electrode portion and the second electrode portion, is magnetized itself, and generates an electromotive force within itself due to the Hall effect that occurs when current flows in the direction from the first electrode portion to the second electrode portion, It includes a calculation unit (60) connected to a Hall effect generating unit, which detects the electromotive force generated by the Hall effect generating unit and detects the magnitude of the current flowing between the first electrode unit and the second electrode unit based on the detected electromotive force, The Hall effect generating section consists of a magnet (31) that generates a magnetic field and a non-magnetic material (33) which is made of a material that does not interact with the magnetic field generated by the magnet, and generates an electromotive force by generating a normal Hall effect when the magnetic field generated by the magnet is applied. A magnet generates a magnetic field strength that is less than the magnetic field strength required for a magnetic material to reach saturation magnetization.

[0010] According to this, the current detection device detects the electromotive force generated in the Hall effect generating section by the calculation section connected to the Hall effect generating section. Therefore, even when the temperature of the first electrode section and the second electrode section changes due to the flow of current through the first electrode section and the second electrode section, and their resistance values change, it is difficult for the detection result of the electromotive force of the Hall effect generating section detected by the calculation section to be affected. Thus, a compensation circuit or the like for compensating for an error in the detection value caused by the temperature change of the first electrode section and the second electrode section can be made unnecessary, and the current value can be accurately detected with a simple configuration.

[0011] The reference numerals with parentheses attached to each component or the like indicate an example of the correspondence relationship between the component or the like and the specific components or the like described in the embodiments described later.

Brief Description of the Drawings

[0012] [Figure 1] It is a schematic configuration diagram of a current detection device according to the first embodiment. [Figure 2] It is for explaining the operation of the current detection device according to the first embodiment. [Figure 3] It is a diagram showing the relationship between the magnetic field strength and the magnitude of magnetization. [Figure 4] It is a schematic configuration diagram of a current detection device of a comparative example. [Figure 5] It is a schematic configuration diagram of a current detection device according to the second embodiment. [Figure 6] This is a schematic diagram of the current detection device according to the third embodiment. [Modes for carrying out the invention]

[0013] Embodiments of this disclosure will be described below with reference to the drawings. In the following embodiments, parts that are the same as or equivalent to those described in the prior embodiments will be denoted by the same reference numerals, and their descriptions may be omitted. Also, if only a part of a component is described in an embodiment, the components described in the prior embodiments can be applied to the other parts of that component. The following embodiments can be partially combined with each other, even if not explicitly stated, as long as it does not impede the combination.

[0014] (First Embodiment) This embodiment will be described with reference to Figures 1 and 2. The current detection device 1 of this embodiment is installed in an electric vehicle and is used to measure the magnitude of the current flowing through the battery of the electric vehicle. As shown in Figure 1, the current detection device 1 comprises a first electrode section 10, a second electrode section 20, a Hall effect generating section 30, a terminal section 40, an electric wire 50, and a calculation section 60.

[0015] The first electrode section 10 and the second electrode section 20 are conductive conductors and are busbars for conducting current to the current detection device 1. The first electrode section 10 and the second electrode section 20 are rectangular parallelepipeds and are formed in the shape of thin plates. In this embodiment, the first electrode section 10 and the second electrode section 20 are made of the same material and have the same shape, and are made of, for example, copper, which is a conductive metal. A Hall effect generating section 30 is provided between the first electrode section 10 and the second electrode section 20. The first electrode section 10 and the second electrode section 20 may be made of different materials or may be formed in different shapes.

[0016] In the following description, as shown in Figure 1, the direction in which the first electrode section 10, the Hall effect generating section 30, and the second electrode section 20 are aligned is defined as the X direction, and the direction perpendicular to the X direction and corresponding to the plate thickness of the first electrode section 10 and the second electrode section 20 is defined as the Y direction. The direction perpendicular to both the X and Y directions is defined as the Z direction. The current detection device 1 of this embodiment measures the current value of the current flowing from the first electrode section 10 to the second electrode section 20 along the direction from the first electrode section 10 to the second electrode section 20.

[0017] Therefore, in the following, the direction in the X direction from the first electrode section 10 to the second electrode section 20 will be defined as the current flow direction. In the Y direction, the direction toward the upper side in Figure 1 will be defined as the upward direction, and the direction toward the lower side will be defined as the downward direction. In the Z direction, the direction toward the back side in Figure 1 will be defined as the back direction, and the direction toward the front side will be defined as the front direction.

[0018] The Hall effect generating section 30 is a component that generates an electromotive force within itself through the Hall effect when current flows across the Hall effect generating section 30 from the first electrode section 10 to the second electrode section 20 along the direction of current flow. The Hall effect generating section 30 is rectangular parallelepiped in shape, with its dimensions in the Y direction being the same as those of the first electrode section 10 and the second electrode section 20 in the Y direction, and its dimensions in the Z direction being the same as those of the first electrode section 10 and the second electrode section 20 in the Z direction. In contrast, the dimensions of the Hall effect generating section 30 in the X direction are smaller than those of the first electrode section 10 and the second electrode section 20 in the X direction.

[0019] Furthermore, the Hall effect generating unit 30 is made of a magnetic material that can magnetize itself. Here, magnetization includes generating a magnetic field around itself through spontaneous magnetization that is spontaneously formed within itself without being affected by an external magnetic field, and generating a magnetic field around itself by being magnetized under the influence of an externally applied magnetic field.

[0020] Furthermore, the Hall effect is the phenomenon in which an electromotive force is generated in an object when an electric current flows through it, due to the influence of a magnetic field, in a direction perpendicular to the direction of current flow and magnetization within the object. There are two types of Hall effects: the anomalous Hall effect and the normal Hall effect. The anomalous Hall effect occurs when an electric current flows through a magnetic material that has spontaneous magnetization. The electromotive force generated by the anomalous Hall effect increases with increasing magnetic field strength of the magnetic material with spontaneous magnetization.

[0021] In contrast, the normal Hall effect occurs when an object that does not possess ferromagnetism (e.g., a non-magnetic material) is affected by an external magnetic field, causing the Lorentz force to bend the orbit of electrons, resulting in an electric current flowing through the object. Furthermore, the electromotive force generated by the normal Hall effect increases with increasing external magnetic field strength. Generally speaking, the electromotive force generated by the normal Hall effect tends to be smaller than that generated by the anomalous Hall effect.

[0022] The Hall effect generating unit 30 in this embodiment is configured to maintain spontaneous magnetization even without being affected by an external magnetic field, by being pre-magnetized. In other words, the Hall effect generating unit 30 is configured to maintain the direction of spontaneous magnetization even when the magnetic field strength in the surrounding environment is zero, by being pre-magnetized. Hereinafter, the direction of magnetization will also be referred to as the magnetization direction.

[0023] In this embodiment, the Hall effect generating unit 30 is arranged so that its magnetization direction is perpendicular to the direction of current flow. Specifically, the Hall effect generating unit 30 is arranged so that its magnetization direction overlaps with the upward direction. With the Hall effect generating unit 30 arranged in this way, when current flows in the direction of current flow through the Hall effect generating unit 30, an abnormal Hall effect occurs in the magnetized Hall effect generating unit 30. As a result, electromotive force is generated in the front and back portions of the Hall effect generating unit 30 in the Z direction.

[0024] The Hall effect generating unit 30 is connected to the first electrode unit 10 and the second electrode unit 20 by connecting means such as crimping, while it is pre-magnetized. Alternatively, the Hall effect generating unit 30 may be magnetized after being connected to the first electrode unit 10 and the second electrode unit 20.

[0025] Furthermore, the Hall effect generating section 30 of this embodiment is composed of a Heusler alloy that has a relatively high anomalous Hall coefficient and whose Curie temperature at which spontaneous magnetization disappears is above room temperature (for example, 30°C).

[0026] A Heusler alloy is, for example, one having the composition "XYZ" or "X2YZ". Here, "X" is, for example, Co (i.e., cobalt) from the periodic table. "Y" is, for example, at least one selected from the group consisting of V (i.e., vanadium), Cr (i.e., chromium), Mn (i.e., manganese), and Fe (i.e., iron) from the periodic table. "Z" is at least one selected from the group consisting of Al (i.e., aluminum), Si (i.e., silicon), Ga (i.e., gallium), and Ge (i.e., germanium) from the periodic table.

[0027] Examples of such Heusler alloys include Co2FeSi, Co2FeGe, Co2FeGa, Co2MnSi, Co2MnAl, and Co2FeGe. In this embodiment, Co2MnAl, which contains cobalt, is used among the Heusler alloys, and the Hall effect generating section 30 is made of Co2MnAl. The Hall effect generating section 30 may also be made of Co2FeSi, which contains iron, among the Heusler alloys.

[0028] The Hall effect generating unit 30 is provided with terminals 40 on both the front and back sides in the Z direction for detecting the electromotive force (i.e., abnormal Hall voltage) generated in the Hall effect generating unit 30 due to the abnormal Hall effect. Specifically, the terminals 40 are attached to the surface of the Hall effect generating unit 30 in a direction perpendicular to the current flow direction and the magnetization direction. A calculation unit 60 is connected to the terminals 40 via an electric wire 50. This allows the calculation unit 60 to detect the value of the abnormal Hall voltage generated in the Hall effect generating unit 30 via the terminals 40 and the electric wire 50.

[0029] The calculation unit 60 calculates the value of the current flowing through the Hall effect generating unit 30 based on the value of the abnormal Hall voltage generated in the Hall effect generating unit 30. The calculation unit 60 consists of an amplification circuit that amplifies the signal related to the value of the abnormal Hall voltage output by the Hall effect generating unit 30, a microcomputer which includes a CPU, ROM, RAM and other memory units, and peripheral circuits thereof.

[0030] The calculation unit 60 calculates the value of the current flowing through the Hall effect generating unit 30 by performing various calculations and processing based on a control map determined based on the value of the abnormal Hall voltage of the Hall effect generating unit 30 and the value of the current flowing through the Hall effect generating unit 30, which are stored in the memory unit. The control map determined based on the value of the abnormal Hall voltage generated in the Hall effect generating unit 30 and the value of the current flowing through the Hall effect generating unit 30 can be obtained from experimental results or the like, which are performed in advance.

[0031] The calculation unit 60 may also calculate the value of the current flowing through the Hall effect generating unit 30 based on the value of the abnormal Hall voltage generated in the Hall effect generating unit 30 and the magnetic field strength when the Hall effect generating unit 30 spontaneously magnetizes.

[0032] The operation of the current detection device 1 with the above configuration will be explained below with reference to Figure 2. The current detection device 1 has a first electrode section 10 and a second electrode section 20 connected in series to a battery (not shown), which is a symmetrical object for detecting the magnitude of the current. As a result, as shown in Figure 2, current flows from the first electrode section 10 to the second electrode section 20. At this time, the current flows in the direction of current flow in the Hall effect generating section 30 via the first electrode section 10 and the second electrode section 20.

[0033] Here, the Hall effect generating unit 30 is pre-magnetized, so that it maintains an upward magnetization direction, as shown in Figure 2, even without being affected by an external magnetic field. Therefore, when current flows through the Hall effect generating unit 30, an abnormal Hall effect occurs in the Hall effect generating unit 30, and an abnormal Hall voltage is generated in the Z direction, which is perpendicular to the current flow direction and the magnetization direction in the Hall effect generating unit 30. Specifically, the Hall effect generating unit 30 becomes positively charged on the far side and negatively charged on the near side.

[0034] Incidentally, the abnormal Hall voltage generated by the abnormal Hall effect increases as the magnitude of the magnetization of the Hall effect generating unit 30 increases, provided that the current flowing through the Hall effect generating unit 30 is constant. And, as shown in Figure 3, the magnitude of this magnetization increases as the magnetic field strength of the Hall effect generating unit 30 increases. In Figure 3, the vertical axis represents the magnitude of the magnetization of the Hall effect generating unit 30, and the horizontal axis represents the magnetic field strength of the Hall effect generating unit 30.

[0035] Specifically, within the range of the magnetic field strength of the Hall effect generating unit 30 from 0 to a predetermined value, the magnitude of magnetization increases approximately proportionally to the magnetic field strength of the Hall effect generating unit 30. When the magnetic field strength of the Hall effect generating unit 30 exceeds the predetermined value, the increase in the magnitude of magnetization in response to the change in the magnitude of the magnetic field strength of the Hall effect generating unit 30 decreases rapidly. Furthermore, as the magnetic field strength of the Hall effect generating unit 30 increases, the magnitude of magnetization of the Hall effect generating unit 30 reaches a saturation magnetization where the magnetization does not increase approximately even when the magnetic field strength of the Hall effect generating unit 30 increases.

[0036] Therefore, if the objective is to maximize the abnormal Hall voltage generated by the abnormal Hall effect, it is conceivable to set the magnetic field strength of the Hall effect generating unit 30 to the maximum possible value and bring the magnitude of the magnetization of the Hall effect generating unit 30 closer to the saturation magnetization.

[0037] However, the magnitude of magnetization of the Hall effect generating unit 30 is affected by the external temperature and the temperature of the Hall effect generating unit 30 itself. Specifically, when the magnetic field strength of the Hall effect generating unit 30 is set to saturation magnetization, as shown in Figure 3, the lower the external temperature and the temperature of the Hall effect generating unit 30 itself, the greater the magnitude of magnetization of the Hall effect generating unit 30. Conversely, when the magnetic field strength of the Hall effect generating unit 30 is set to saturation magnetization, the higher the external temperature and the temperature of the Hall effect generating unit 30 itself, the smaller the magnitude of magnetization of the Hall effect generating unit 30.

[0038] In Figure 3, the solid line shows the relationship between the magnetic field strength and magnetization magnitude of the Hall effect generating unit 30 when the ambient temperature is 25°C. The dashed line shows the relationship between the magnetic field strength and magnetization magnitude of the Hall effect generating unit 30 when the ambient temperature is 100°C. The dashed line shows the relationship between the magnetic field strength and magnetization magnitude of the Hall effect generating unit 30 when the ambient temperature is 150°C.

[0039] Furthermore, x1, x2, and x3 in Figure 3 represent the magnetic field strength at which the Hall effect generating section 30 reaches saturation magnetization when the external temperature is 25°C, 100°C, and 150°C, respectively. And y1, y2, and y3 in Figure 3 represent the saturation magnetization at 25°C, 100°C, and 150°C, respectively.

[0040] The magnetic field strength at which the increase in magnetization magnitude in response to a change in the magnetic field strength of the Hall effect generating unit 30 becomes rapidly smaller increases as the external temperature and the temperature of the Hall effect generating unit 30 itself decrease. In other words, the lower the external temperature and the temperature of the Hall effect generating unit 30 itself, the larger the range of magnetization magnitude that increases approximately proportionally to the magnetic field strength of the Hall effect generating unit 30. That is, the higher the external temperature and the temperature of the Hall effect generating unit 30 itself, the smaller the range of magnetization magnitude that increases approximately proportionally to the magnetic field strength of the Hall effect generating unit 30.

[0041] Therefore, if the magnetic field strength of the Hall effect generating unit 30 is set so that the magnitude of magnetization of the Hall effect generating unit 30 approaches saturation magnetization, the influence of changes in external temperature and the temperature of the Hall effect generating unit 30 on the change in the magnitude of magnetization of the Hall effect generating unit 30 tends to increase. In other words, if the magnetic field strength of the Hall effect generating unit 30 is set so that the magnitude of magnetization of the Hall effect generating unit 30 approaches saturation magnetization, the abnormal Hall voltage generated by the abnormal Hall effect becomes more susceptible to changes in external temperature and the temperature of the Hall effect generating unit 30 itself.

[0042] Therefore, the magnetic field strength of the Hall effect generating unit 30 is set such that the magnitude of magnetization of the Hall effect generating unit 30 when the external temperature is a predetermined temperature is smaller than the magnitude of the magnetic field strength at which it saturates. Specifically, the magnetic field strength of the Hall effect generating unit 30 may be set to be 80% or less of the magnitude of the magnetic field strength at which the Hall effect generating unit 30 saturates when the external temperature is 25°C.

[0043] In Figure 3, x4 represents 80% of the magnetic field strength at which the Hall effect generating section 30 reaches saturation magnetization when the ambient temperature is 25°C.

[0044] For example, when the current detection device 1 is used in an environment where the ambient temperature is 150°C or lower, and the magnitude of the magnetic field strength of the Hall effect generating unit 30 is set to 80% or less of the magnetic field strength at which the Hall effect generating unit 30 saturates, the magnitude of magnetization will be approximately equal regardless of the ambient temperature or the temperature of the Hall effect generating unit 30 itself, as shown in Figure 3. Also, when the current detection device 1 is used in an environment where the ambient temperature is 150°C or lower, and the magnitude of the magnetic field strength of the Hall effect generating unit 30 is set to 80% or less of the magnetic field strength at which the Hall effect generating unit 30 saturates, the magnitude of the magnetic field will be approximately proportional to the magnetic field strength of the Hall effect generating unit 30.

[0045] Therefore, in this embodiment, the Hall effect generating unit 30 is configured to have a magnetic field strength that is 80% or less of the magnitude of the magnetic field strength at which the Hall effect generating unit 30 saturates when the ambient temperature is 25°C. This makes the abnormal Hall voltage generated by the abnormal Hall effect less susceptible to changes in ambient temperature and the temperature of the Hall effect generating unit 30 itself.

[0046] Furthermore, generally speaking, the cost of the Hall effect generating unit 30 tends to increase as the set value of the magnetic field strength increases. Therefore, by setting the magnetic field strength of the Hall effect generating unit 30 to be 80% or less of the magnitude of the magnetic field strength at which the Hall effect generating unit 30 saturates, it is possible to suppress the increase in the cost of the Hall effect generating unit 30. The abnormal Hall voltage generated by the Hall effect generating unit 30 configured in this way is then detected by the calculation unit 60.

[0047] As mentioned above, the higher the external temperature and the temperature of the Hall effect generating unit 30 itself, the smaller the range of the magnitude of magnetization, which increases approximately in proportion to the magnetic field strength of the Hall effect generating unit 30. In other words, the higher the external temperature and the temperature of the Hall effect generating unit 30 itself, the smaller the range in which the abnormal Hall voltage generated by the abnormal Hall effect is susceptible to changes in the external temperature and the temperature of the Hall effect generating unit 30 itself.

[0048] In contrast, by setting the magnitude of the magnetic field strength of the Hall effect generating unit 30 to be smaller than the magnitude of the magnetic field strength at which the Hall effect generating unit 30 saturates, it becomes easier to suppress the influence of abnormal Hall voltage on the rise in external temperature and the temperature of the Hall effect generating unit 30 itself.

[0049] Therefore, the Hall effect generating unit 30 may be set to a magnetic field strength that is 1 / 2 or less of the magnetic field strength at which the Hall effect generating unit 30 saturates when the ambient temperature is 25°C.

[0050] According to this, even at external temperatures higher than 150°C, the abnormal Hall voltage generated by the abnormal Hall effect can be made less susceptible to changes in external temperature and the temperature of the Hall effect generating unit 30 itself. Furthermore, it becomes easier to suppress increases in the cost of the Hall effect generating unit 30.

[0051] Furthermore, the magnetic field strength of the Hall effect generating unit 30 may be set to be 80% or less of the magnetic field strength at which the Hall effect generating unit 30 saturates when the external temperature is different from 25°C. For example, the magnetic field strength of the Hall effect generating unit 30 may be set to be 80% or less of the magnetic field strength at which the Hall effect generating unit 30 saturates when the external temperature is lower than 25°C. Alternatively, the magnetic field strength of the Hall effect generating unit 30 may be set to be 80% or less of the magnetic field strength at which the Hall effect generating unit 30 saturates when the external temperature is higher than 25°C.

[0052] The calculation unit 60 is connected to the Hall effect generating unit 30 via the terminal unit 40 and the electric wire 50, and detects the value of the abnormal Hall voltage generated in the Hall effect generating unit 30. The calculation unit 60 then calculates the magnitude of the current flowing through the Hall effect generating unit 30 based on the detected abnormal Hall voltage value and a defined control map.

[0053] As described above, the current detection device 1 of this embodiment calculates the current value based on the electromotive force generated in the Hall effect generating unit 30 due to the abnormal Hall effect when current flows through the Hall effect generating unit 30.

[0054] Here, the effects of the present invention will be explained using a current detection device 100, which is a comparative example using a shunt resistor. As shown in Figure 4, the current detection device 100, which is a comparative example, has electrode sections 101 and 102, a resistor 103 provided between the electrode sections 101 and 102, two terminals 104 provided on the electrode sections 101 and 102 to detect the voltage drop across the resistor 103, and a current calculation unit 105 that calculates a current value based on the potential difference between the two terminals 104.

[0055] In the comparative example, the current detection device 100 has a current calculation unit 105 that detects the voltage drop across the resistor 103 using two terminals 104 provided on the electrode sections 101 and 102, and calculates the current value of the current flowing through the resistor 103 using Ohm's law.

[0056] Incidentally, in the comparative example current detection device 100, there is a risk that the temperatures of the electrode parts 101 and 102 and the resistor 103 will change as current flows through them. In particular, when the comparative example current detection device 100 is used to detect the current flowing through the battery of an electric vehicle, the temperature of the electrode parts 101 and 102 and the resistor 103 is likely to rise because currents of 1000 amperes or more can flow through the battery of an electric vehicle.

[0057] When the temperature of the electrodes 101, 102 and the resistor 103 changes, the resistance values ​​of these electrodes 101, 102, and the resistor 103 change. Each of these changes in resistance values, both for electrodes 101 and 102 and resistor 103, causes a change in the voltage drop between the two terminals 104. In other words, the change in resistance values ​​caused by temperature changes in electrodes 101, 102, and the resistor 103 causes an error in the current value calculated based on the voltage drop.

[0058] Furthermore, the current calculation unit 105 calculates the current value of the current flowing through the resistor 103 using Ohm's law. Therefore, changes in resistance values ​​due to temperature changes in the electrode units 101, 102 and the resistor 103 tend to increase the error in the detected current value.

[0059] In contrast, the current detection device 1 of this embodiment has a terminal 40 provided on the Hall effect generating section 30 for detecting the electromotive force generated in the Hall effect generating section 30. Therefore, even if the resistance values ​​of the first electrode section 10 and the second electrode section 20 change due to temperature changes in the first electrode section 10 and the second electrode section 20, the detection result of the electromotive force of the Hall effect generating section 30 detected by the current detection device 1 is less likely to be affected. As a result, a compensation circuit or the like to compensate for errors in the detected value due to temperature changes in the first electrode section 10 and the second electrode section 20 can be eliminated, and the current value can be detected accurately with a simple configuration.

[0060] Furthermore, the current detection device 1 detects the electromotive force generated in the Hall effect generating section 30 due to the abnormal Hall effect. The electromotive force generated by the abnormal Hall effect is relatively unaffected by the temperature of the Hall effect generating section 30 and the magnitude of the electrical resistance of the Hall effect generating section 30.

[0061] Therefore, even when the temperature of the Hall effect generating section 30 changes due to the flow of current through it, the current value can be detected with greater accuracy compared to methods that calculate the current value using Ohm's law, such as the current detection device 100 in the comparative example.

[0062] Furthermore, according to the above embodiment, the following effects can be obtained.

[0063] (1) In the above embodiment, the Hall effect generating unit 30 is made of a magnetic material that has spontaneous magnetization and maintains the direction of spontaneous magnetization even without being affected by a magnetic field from outside the Hall effect generating unit 30.

[0064] Therefore, since it is not necessary to separately provide a member for generating a magnetic field to magnetize the Hall effect generating unit 30, and an abnormal Hall effect can be generated in the Hall effect generating unit 30, the configuration of the current detection device 1 can be simplified.

[0065] Furthermore, if a member is provided that magnetizes the Hall effect generating unit 30 independently of the Hall effect generating unit 30, an electromotive force will be generated in the Hall effect generating unit 30 by the magnetic field of the member that generates the magnetic field. However, the magnetic field strength of the member that generates the magnetic field may change due to influences from the external environment, etc. Since the electromotive force generated in the Hall effect generating unit 30 changes in accordance with the change in the magnetic field strength of the member that generates the magnetic field, if the magnetic field strength of the member that generates the magnetic field changes due to influences from the external environment, etc., there is a risk that an error will occur in the current value detected by the current detection device 1.

[0066] In contrast, by using a Hall effect generating unit 30 that has spontaneous magnetization, it is possible to eliminate the need for a member to magnetize the Hall effect generating unit 30, thereby reducing the factors that cause errors in the current value detected by the current detection device 1 due to influences from the external environment, etc. Therefore, compared to the case where a member to magnetize the Hall effect generating unit 30 is provided independently of the Hall effect generating unit 30, it is possible to make it less likely for errors to occur in the current value detected by the current detection device 1.

[0067] (2) In the above embodiment, the Hall effect generating section 30 is made of a Heusler alloy having a relatively high abnormal Hall coefficient. The higher the abnormal Hall coefficient of the Hall effect generating section 30, the greater the electromotive force generated in the Hall effect generating section 30 by the abnormal Hall effect.

[0068] Furthermore, the larger the electromotive force generated in the Hall effect generating section 30, the easier it is to detect changes in the current value flowing through the Hall effect generating section 30. Therefore, the current detection device 1 can detect the current value with greater accuracy compared to the case where the Hall effect generating section 30 is made of a metal other than the Heusler alloy.

[0069] (3) In the above embodiment, the Hall effect generating unit 30 is made of a Heusler alloy and contains at least one of cobalt and iron. The Hall effect generating unit 30 is more likely to produce a large abnormal Hall coefficient compared to the case in which the Hall effect generating unit 30 does not contain cobalt and iron. For this reason, the current detection device 1 can detect the current value with greater accuracy compared to the case in which the Hall effect generating unit 30 does not contain cobalt and iron.

[0070] (4) In the above embodiment, the Hall effect generating unit 30 is arranged such that the magnetization direction of the Hall effect generating unit 30 is perpendicular to the direction of current flow. Incidentally, in the abnormal Hall effect, an electromotive force is generated in the Hall effect generating unit 30 in a direction perpendicular to the direction of current flow and the magnetization direction. For this reason, the smaller the component in the direction perpendicular to the direction of current flow in the magnetization direction of the Hall effect generating unit 30, the smaller the electromotive force generated in the Hall effect generating unit 30 becomes.

[0071] In contrast, in this embodiment, the Hall effect generating unit 30 is arranged such that its magnetization direction is perpendicular to the current flow direction. Therefore, the electromotive force generated in the Hall effect generating unit 30 can be increased compared to the case where it is not arranged in this way. Consequently, the current detection device 1 can detect the current value with greater accuracy compared to the case where the Hall effect generating unit 30 is made of a metal other than the Heusler alloy.

[0072] (5) In the above embodiment, the magnetic field strength of the Hall effect generating unit 30 is set to be 80% or less of the magnitude of the magnetic field strength at which the Hall effect generating unit 30 saturates. As a result, the abnormal Hall voltage generated by the abnormal Hall effect is less affected by changes in external temperature and the temperature of the Hall effect generating unit 30 itself. Therefore, since the Hall voltage is less likely to change due to changes in external temperature and the temperature of the Hall effect generating unit 30 itself, the current value can be detected with greater accuracy compared to when it is not configured in this way. In addition, it is easier to suppress the increase in cost of the Hall effect generating unit 30 compared to when it is not configured in this way.

[0073] (Second Embodiment) Next, a second embodiment will be described with reference to Figure 5. This embodiment differs from the first embodiment in that the Hall effect generating unit 30 is composed of a magnet 31 and an abnormal Hall effect material 32. In this embodiment, the parts that differ from the first embodiment will be mainly described, and the parts that are the same as the first embodiment may be omitted from the description.

[0074] The magnet 31 is a magnetic field generating unit that applies a constant magnetic field to the anomalous Hall effect material 32 by generating a magnetic field of a predetermined magnetic field strength around itself and maintaining its own magnetization direction. As shown in Figure 5, the magnet 31 is rectangular in shape and is located on the underside of the anomalous Hall effect material 32.

[0075] Furthermore, the magnet 31 is positioned such that its upper side is the north pole and its lower side is the south pole. The magnet 31 is also positioned so that the magnetization direction of the magnetic field applied to the anomalous Hall effect material 32 is upward. In other words, the magnet 31 is positioned so that a magnetic field perpendicular to the direction of current flow can be applied to the anomalous Hall effect material 32.

[0076] The abnormal Hall effect material 32 in this embodiment is a Heusler alloy, specifically Co2MnAl containing cobalt, similar to the Hall effect generating unit 30 in the first embodiment. However, unlike the Hall effect generating unit 30 in the first embodiment, the abnormal Hall effect material 32 is not magnetized and, when not affected by an external magnetic field, cannot generate a magnetic field around itself.

[0077] However, the anomalous Hall effect material 32 is magnetized by the influence of the magnetic field generated by the magnet 31, and is configured to maintain its magnetization direction in the direction of magnetization received from the magnet 31, due to the influence of the magnetic field generated by the magnet 31. In other words, the anomalous Hall effect material 32 is magnetized in a direction perpendicular to the direction of current flow due to the influence of the magnetic field generated by the magnet 31, and is configured to maintain its magnetization direction. To put it another way, when the anomalous Hall effect material 32 is no longer influenced by the magnetic field from the magnet 31, it cannot maintain the state of being magnetized in a direction perpendicular to the direction of current flow, and cannot maintain the magnetization direction that was positioned by the magnet 31.

[0078] Specifically, the abnormal Hall effect material 32 of this embodiment is configured to maintain its magnetization direction upward, that is, perpendicular to the direction of current flow, by an upward magnetic field supplied from the magnet 31.

[0079] Furthermore, the abnormal Hall effect material 32 may be one that magnetizes in a direction other than the direction perpendicular to the current flow when it is not affected by the magnetic field from the magnet 31.

[0080] Therefore, when an electric current flows through the anomalous Hall effect material 32, which is magnetized by the magnetic field generated by the magnet 31, an anomalous Hall effect occurs in the magnetized anomalous Hall effect material 32, and an anomalous Hall voltage is generated.

[0081] The abnormal Hall voltage generated in the abnormal Hall effect material 32 increases as the magnetic field strength of the magnet 31 increases, similar to the abnormal Hall voltage generated in the Hall effect generating unit 30 described in the first embodiment. Furthermore, the change in the abnormal Hall voltage generated in the abnormal Hall effect material 32 changes in the same way as the change in the abnormal Hall voltage generated in the Hall effect generating unit 30.

[0082] Therefore, the magnet 31 in this embodiment is designed to generate a magnetic field strength that is 80% or less of the magnitude of the magnetic field strength at which the anomalous Hall effect material 32 becomes saturated. As a result, the anomalous Hall voltage generated by the anomalous Hall effect is less susceptible to changes in external temperature and the temperature of the anomalous Hall effect material 32 itself.

[0083] Furthermore, the greater the magnetic field strength that the magnet 31 can generate, the more likely the cost of the magnet 31 itself is to increase. Therefore, by using a magnet 31 that generates a magnetic field that is 80% or less of the magnetic field strength at which the anomalous Hall effect material 32 becomes saturated, it is possible to suppress the increase in the cost of the magnet 31.

[0084] In the current detection device 1 configured in this way, when a magnetic field is applied from the magnet 31 to the abnormal Hall effect material 32 via the first electrode section 10 and the second electrode section 20, and current flows in the direction of current flow, an abnormal Hall effect occurs in the abnormal Hall effect material 32. As a result, an electromotive force is generated in the abnormal Hall effect material 32 in the Z direction, which is perpendicular to the direction of current flow and the upward direction.

[0085] The calculation unit 60 is connected to the abnormal Hall effect material 32 via the terminal unit 40 and the electric wire 50, and detects the value of the abnormal Hall voltage generated in the abnormal Hall effect material 32. The calculation unit 60 then calculates the magnitude of the current flowing through the abnormal Hall effect material 32 based on the detected abnormal Hall voltage value and a defined control map.

[0086] As described above, the current detection device 1 of this embodiment calculates the current value based on the electromotive force generated in the abnormal Hall effect material 32 due to the abnormal Hall effect when current flows through the abnormal Hall effect material 32.

[0087] Thus, the current detection device 1 of this embodiment differs from the first embodiment in that the Hall effect generating unit 30 is replaced by a magnet 31 and an abnormal Hall effect material 32. When a magnetic field is applied from the magnet 31, a current flows through the abnormal Hall effect material 32, which maintains its magnetization direction, thereby generating an abnormal Hall effect in the abnormal Hall effect material 32. This allows the same effects as the first embodiment to be obtained.

[0088] Furthermore, according to the above embodiment, the following effects can be obtained.

[0089] (1) In the above embodiment, the magnet 31 is designed to generate a magnetic field strength that is 80% or less of the magnitude of the magnetic field strength at which the abnormal Hall effect material 32 becomes saturated. This makes the abnormal Hall voltage generated by the abnormal Hall effect less susceptible to changes in external temperature and the temperature of the abnormal Hall effect material 32 itself. Therefore, since the Hall voltage is less likely to change due to changes in external temperature and the temperature of the abnormal Hall effect material 32 itself, the current value can be detected with greater accuracy compared to cases where this configuration is not used. In addition, the cost increase of the magnet 31 can be more easily suppressed compared to cases where this configuration is not used.

[0090] (Third embodiment) Next, the third embodiment will be described with reference to Figure 6. This embodiment differs from the second embodiment in that the abnormal hole effect material 32 is replaced with a normal hole effect material 33. In this embodiment, the parts that differ from the second embodiment will be mainly described, and the parts that are the same as the second embodiment may be omitted from the description.

[0091] The normal Hall effect material 33 in this embodiment is made of a non-magnetic material that has the property of not interacting with the magnetic field generated by the magnet 31. In other words, the normal Hall effect material 33 in this embodiment is made of a non-magnetic material that does not generate a magnetic field around itself by being affected by the magnetic field generated by the magnet 31.

[0092] Specifically, the normal Hall effect material 33 is composed of an alloy containing copper and manganese. More specifically, the normal Hall effect material 33 is composed of manganin®, which is mainly composed of three components: copper, manganese, and nickel.

[0093] In the normal Hall effect material 33 configured in this way, when an electric current flows through the normal Hall effect material 33, the current is not significantly affected by the magnetic field from the normal Hall effect material 33, but is affected by the magnetic field generated by the magnet 31. Therefore, when an electric current flows through the normal Hall effect material 33, which is not significantly affected by the magnetic field generated by the magnet 31, the normal Hall effect occurs in the normal Hall effect material 33.

[0094] In the current detection device 1 configured in this way, when current flows through the normal Hall effect material 33 via the first electrode section 10 and the second electrode section 20 in the direction of current flow, a magnetic field is applied from the magnet 31, causing the normal Hall effect to occur in the normal Hall effect material 33. As a result, an electromotive force (i.e., a normal Hall voltage) is generated in the normal Hall effect material 33 in the Z direction perpendicular to the direction of current flow and upward.

[0095] The calculation unit 60 is connected to the normal Hall effect material 33 via the terminal unit 40 and the electric wire 50, and detects the value of the normal Hall voltage generated in the normal Hall effect material 33. The calculation unit 60 then calculates the magnitude of the current flowing through the normal Hall effect material 33 based on the detected value of the normal Hall voltage and a defined control map.

[0096] As described above, the current detection device 1 of this embodiment calculates the current value based on the electromotive force generated in the normal Hall effect material 33 by the normal Hall effect when current flows through the normal Hall effect material 33.

[0097] Thus, the current detection device 1 of this embodiment differs from the second embodiment in that the abnormal Hall effect material 32 is replaced with a normal Hall effect material 33. When current flows through the normal Hall effect material 33, the normal Hall effect can be generated in the normal Hall effect material 33. As a result, the same effects as the second embodiment can be obtained.

[0098] Furthermore, according to the above embodiment, the following effects can be obtained.

[0099] (1) In the above embodiment, the normal Hall effect material 33 is composed of both copper and manganese. Compared to the case in which the normal Hall effect material 33 does not contain copper and manganese, it is easier to increase the normal Hall coefficient. For this reason, the current detection device 1 can detect the current value with greater accuracy compared to the case in which the normal Hall effect material 33 does not contain copper and manganese.

[0100] (Other embodiments) While representative embodiments of this disclosure have been described above, this disclosure is not limited to the embodiments described above and can be modified in various ways, for example, as follows.

[0101] In the embodiments described above, an example was given in which the current detection device 1 is used to detect the current of an electric vehicle battery, but it is not limited to this. The object for which the current detection device 1 detects the current value is not limited to an electric vehicle battery, and the current detection device 1 can measure the current value flowing through various objects.

[0102] In the above-described embodiment, an example was given in which the Hall effect generating section 30 and the abnormal Hall effect material 32 are composed of a Heusler alloy, but the invention is not limited to this. For example, the Hall effect generating section 30 and the abnormal Hall effect material 32 may be composed of materials other than a Heusler alloy.

[0103] In the embodiments described above, an example was described in which the Hall effect generating section 30 and the abnormal Hall effect material 32 are composed of a Heusler alloy containing at least one of cobalt and iron, but the invention is not limited to this. For example, the Hall effect generating section 30 and the abnormal Hall effect material 32 may be composed of a Heusler alloy that does not contain cobalt and iron.

[0104] In the above-described embodiment, an example was given in which the Hall effect generating unit 30 is arranged such that the direction of spontaneous magnetization of the Hall effect generating unit 30 is perpendicular to the direction of current flow, but it is not limited to this. The direction in which the Hall effect generating unit 30 is arranged is not particularly limited as long as the direction of spontaneous magnetization of the Hall effect generating unit 30 is different from the direction parallel to the direction of current flow.

[0105] In the first embodiment described above, an example was described in which the magnetic field strength of the Hall effect generating unit 30 is set to be 80% or less of the magnitude of the magnetic field strength at which the Hall effect generating unit 30 saturates, but the invention is not limited to this. For example, the magnetic field strength of the Hall effect generating unit 30 may be set to be greater than 80% of the magnitude of the magnetic field strength at which the Hall effect generating unit 30 saturates.

[0106] In the embodiments described above, an example was given in which the normal Hall effect material 33 is composed of copper and manganese, but it is not limited to this. For example, the normal Hall effect material 33 may be composed of no copper and manganese, or no copper and manganese, respectively.

[0107] In the second embodiment described above, an example was given in which the magnet 31 generates a magnetic field strength that is 80% or less of the magnitude of the magnetic field strength at which the anomalous Hall effect material 32 becomes saturated, but the invention is not limited to this. For example, the magnet 31 may be one that generates a magnetic field strength greater than 80% of the magnitude of the magnetic field strength at which the anomalous Hall effect material 32 becomes saturated.

[0108] In the embodiments described above, an example was given in which the magnet 31 is arranged such that the magnetization direction of the magnetic field applied to the abnormal Hall effect material 32 or the normal Hall effect material 33 is perpendicular to the direction of current flow, but the invention is not limited to this. The direction in which the magnet 31 is arranged is not particularly limited, as long as the magnetization direction of the magnetic field applied to the abnormal Hall effect material 32 or the normal Hall effect material 33 is in a direction different from the direction parallel to the direction of current flow.

[0109] In the above-described embodiment, an example was described in which the magnet 31 is provided below the abnormal Hall effect material 32 or the normal Hall effect material 33 so that the magnetization direction of the magnetic field applied to the abnormal Hall effect material 32 or the normal Hall effect material 33 is upward, and the magnet 31 is positioned so that the upper side is the north pole and the lower side is the south pole. However, the embodiment is not limited to this. For example, the magnet 31 may be provided above the abnormal Hall effect material 32 or the normal Hall effect material 33 so that the magnetization direction of the magnetic field applied to the abnormal Hall effect material 32 or the normal Hall effect material 33 is upward, and the magnet 31 is positioned so that the upper side is the north pole and the lower side is the south pole.

[0110] Alternatively, the magnet 31 may be placed below the abnormal Hall effect material 32 or the normal Hall effect material 33 so that the magnetization direction of the magnetic field applied to the abnormal Hall effect material 32 or the normal Hall effect material 33 is in the vertical direction, and the magnet 31 may be positioned so that the upper side of the magnet 31 is the south pole and the lower side is the north pole. Furthermore, the magnet 31 may be placed above the abnormal Hall effect material 32 or the normal Hall effect material 33 so that the magnetization direction of the magnetic field applied to the abnormal Hall effect material 32 or the normal Hall effect material 33 is in the downward direction, and the magnet 31 may be positioned so that the upper side of the magnet 31 is the south pole and the lower side is the north pole.

[0111] In the embodiments described above, it goes without saying that the elements constituting the embodiments are not necessarily essential, except in cases where they are explicitly stated to be essential or where they are clearly considered essential in principle.

[0112] In the embodiments described above, if numerical values ​​such as the number, numerical values, quantities, or ranges of the components of the embodiment are mentioned, the embodiment is not limited to those specific numbers unless explicitly stated as particularly essential or clearly limited to a specific number in principle.

[0113] In the embodiments described above, when referring to the shape, positional relationships, etc. of the components, the definition is not limited to those shapes, positional relationships, etc., unless otherwise specifically stated or when the definition is fundamentally limited to a particular shape, positional relationship, etc. [Explanation of Symbols]

[0114] 10 First electrode part 20 Second electrode part 30 Hole effect generating section 60 Calculation Unit

Claims

1. A current detection device, A first electrode portion (10) having conductivity, A second electrode portion (20) having conductivity, A Hall effect generating unit (30) is provided between the first electrode portion and the second electrode portion, is magnetized itself, and generates an electromotive force within itself by the Hall effect that occurs when a current flows in the direction from the first electrode portion to the second electrode portion, The system includes a calculation unit (60) connected to the Hall effect generating unit, which detects the electromotive force generated by the Hall effect generating unit and detects the magnitude of the current flowing between the first electrode unit and the second electrode unit based on the detected electromotive force, The Hall effect generating unit is made of a magnetic material that has spontaneous magnetization and maintains the direction of spontaneous magnetization even without being affected by a magnetic field from outside the Hall effect generating unit, and is set so that the magnitude of its own magnetization is smaller than the magnitude of the magnetic field strength at which it saturates.

2. The current detection device according to claim 1, wherein the Hall effect generating section includes a Heusler alloy.

3. The current detection device according to claim 2, wherein the Hall effect generating unit includes at least one of cobalt and iron.

4. The current detection device according to any one of claims 1 to 3, wherein the Hall effect generating section is arranged such that the direction of spontaneous magnetization is perpendicular to the direction of current flow from the first electrode section toward the second electrode section.

5. The current detection device according to claim 1, wherein the magnetic field strength of the Hall effect generating unit is set to be 80% or less of the magnitude of the magnetic field strength at which the Hall effect generating unit itself becomes saturated magnetized.

6. A current detection device, A first electrode portion (10) having conductivity, A second electrode portion (20) having conductivity, A Hall effect generating unit (30) is provided between the first electrode portion and the second electrode portion, is magnetized itself, and generates an electromotive force within itself by the Hall effect that occurs when a current flows in the direction from the first electrode portion to the second electrode portion, The system includes a calculation unit (60) connected to the Hall effect generating unit, which detects the electromotive force generated by the Hall effect generating unit and detects the magnitude of the current flowing between the first electrode unit and the second electrode unit based on the detected electromotive force, The Hall effect generating unit includes a magnet (31) that generates a magnetic field and a magnetic material (32) that is magnetized by the influence of the magnetic field generated by the magnet. The magnetic material maintains a direction of magnetization due to the influence of the magnetic field generated by the magnet. The magnet is a current detection device that generates a magnetic field strength smaller than the magnitude of the magnetic field strength at which the magnetic material becomes saturated.

7. The current detection device according to claim 6, wherein the magnetic material comprises a Heusler alloy.

8. The current detection device according to claim 7, wherein the magnetic material comprises at least one of cobalt and iron.

9. The current detection device according to any one of claims 6 to 8, wherein the magnet is arranged such that the direction of the magnetic field when influencing the magnetic material is perpendicular to the direction of current flow from the first electrode portion to the second electrode portion.

10. The current detection device according to claim 6, wherein the magnet generates a magnetic field strength that is 80% or less of the magnitude of the magnetic field strength at which the magnetic material becomes saturated.

11. A current detection device, A first electrode portion (10) having conductivity, A second electrode portion (20) having conductivity, A Hall effect generating unit (30) is provided between the first electrode portion and the second electrode portion, is magnetized itself, and generates an electromotive force within itself by the Hall effect that occurs when a current flows in the direction from the first electrode portion to the second electrode portion, The system includes a calculation unit (60) connected to the Hall effect generating unit, which detects the electromotive force generated by the Hall effect generating unit and detects the magnitude of the current flowing between the first electrode unit and the second electrode unit based on the detected electromotive force, The Hall effect generating unit consists of a magnet (31) that generates a magnetic field, and a non-magnetic material (33) formed of a member that does not interact with the magnetic field generated by the magnet, and which generates an electromotive force by generating a normal Hall effect when the magnetic field generated by the magnet is applied. The magnet is a current detection device that generates a magnetic field strength smaller than the magnitude of the magnetic field strength at which the magnetic material becomes saturated.

12. The current detection device according to claim 11, wherein the non-magnetic material comprises copper and manganese.

13. The current detection device according to claim 11 or 12, wherein the magnet is arranged such that the direction of the magnetic field when influencing the nonmagnetic material is perpendicular to the direction of current flow from the first electrode portion to the second electrode portion.

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