Current measurement system, current measurement device, current measurement method, and current measurement program

Abstract

To improve the accuracy of measuring the electric current flowing through a conductor. [Solution] A current measurement system comprising a magnetic field shield 3 configured to take in the magnetic field H generated by the current I flowing through the cable 9, a magnetic field sensor 4 installed inside the magnetic field shield 3, a predetermined sensor, and a current measuring device, wherein the predetermined sensor is a sensor for detecting the cable 9, the magnetic field sensor 4 detects the magnetic field H at the installation location, and the current measuring device acquires the detection result of the predetermined sensor and the detection result of the magnetic field sensor 4, identifies the center position of the cable 9 based on the acquired detection result of the predetermined sensor, and calculates the current value of the current I flowing through the cable 9 based on the identified center position and the acquired detection result of the magnetic field sensor 4.

Description

Technical Field

[0001] The present invention relates to a current measurement system, a current measurement device, a current measurement method, and a current measurement program.

Background Art

[0002] There is known a current measurement device that measures a magnetic field generated from a current flowing through a cable, which is a conductor to be measured, and measures the current flowing through the cable from the measured magnetic field. Among the current measurement devices as described above, there is known a current measurement device that has a substantially U-shaped magnetic field shield inside a sensor head, installs a cable, which is a conductor, in the magnetic field shield, and installs a magnetic field sensor inside the magnetic field shield.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, it is difficult to improve the measurement accuracy of the current flowing through the conductor. For example, in the above technique, when the central position of the cable through which the current flows is not accurately specified, it is difficult to calculate an accurate current value using the sensor value detected by the magnetic sensor.

[0005] The present invention has been made in view of the above, and can improve the measurement accuracy of the current flowing through the conductor.

Means for Solving the Problems

[0006] A current measuring system according to one embodiment of the present invention comprises a magnetic field shield configured to take in a magnetic field generated by a current flowing through a conductor, a magnetic field sensor installed inside the magnetic field shield, a predetermined sensor, and a current measuring device, wherein the predetermined sensor is a sensor for detecting the conductor, the magnetic field sensor detects a magnetic field at the installation location, and the current measuring device comprises an acquisition unit that acquires the detection result of the predetermined sensor and the detection result of the magnetic field sensor, a identification unit that identifies the center position of the conductor based on the acquired detection result of the predetermined sensor, and a calculation unit that calculates the current value of the current flowing through the conductor based on the identified center position and the acquired detection result of the magnetic field sensor.

[0007] A current measuring device according to one embodiment of the present invention includes: an acquisition unit that acquires the detection result of a conductor detected by a predetermined sensor and acquires the detection result of a magnetic field sensor detected at the installation position by a magnetic field sensor installed in a magnetic field shield configured to take in the magnetic field generated by the current flowing through the conductor; an identification unit that identifies the center position of the conductor based on the acquired detection result of the predetermined sensor; and a calculation unit that calculates the current value of the current flowing through the conductor based on the identified center position and the acquired detection result of the magnetic field sensor.

[0008] A current measurement method according to one embodiment of the present invention involves a computer acquiring the detection result of a conductor detected by a predetermined sensor, acquiring the detection result of a magnetic field sensor installed in a magnetic field shield configured to take in the magnetic field generated by the current flowing through the conductor at the installation location, identifying the center position of the conductor based on the acquired detection result of the predetermined sensor, and calculating the current value of the current flowing through the conductor based on the identified center position and the acquired detection result of the magnetic field sensor.

[0009] A current measurement program according to one embodiment of the present invention causes a computer to perform the following processes: acquire the detection result of a conductor detected by a predetermined sensor; acquire the detection result of a magnetic field detected at the installation location by a magnetic field sensor installed in a magnetic field shield configured to take in the magnetic field generated by the current flowing through the conductor; identify the center position of the conductor based on the acquired detection result of the predetermined sensor; and calculate the current value of the current flowing through the conductor based on the identified center position and the acquired detection result of the magnetic field sensor. [Effects of the Invention]

[0010] According to the present invention, there is an effect that the measurement accuracy of the current flowing through a conductor can be improved. [Brief explanation of the drawing]

[0011] [Figure 1] This figure shows an example configuration and processing example of the current measurement system according to Embodiment 1. [Figure 2] This figure shows an example of the configuration of a magnetic field shield according to Embodiment 1. [Figure 3] This figure shows an example of the configuration of a sensor head according to Embodiment 1. [Figure 4] This is a block diagram showing an example of the configuration of each device in the current measurement system according to Embodiment 1. [Figure 5] This figure shows an example of the first detection data storage unit of the current measuring device according to Embodiment 1. [Figure 6] This figure shows an example of the first position data storage unit of the current measuring device according to Embodiment 1. [Figure 7] This figure shows an example of the current data storage unit of the current measuring device according to Embodiment 1. [Figure 8] This flowchart shows an example of the processing flow of the current measurement system according to Embodiment 1. [Figure 9] This figure shows an example configuration and processing example of the current measurement system according to Embodiment 2. [Figure 10] This figure shows an example of the configuration of a sensor head according to Embodiment 2. [Figure 11] It is a block diagram showing a configuration example of each device of the current measurement system according to Embodiment 2. [Figure 12] It is a diagram showing an example of the second detection data storage unit of the current measurement device according to Embodiment 2. [Figure 13] It is a diagram showing an example of the second position data storage unit of the current measurement device according to Embodiment 2. [Figure 14] It is a flowchart showing an example of the processing flow of the current measurement system according to Embodiment 2. [Figure 15] It is a diagram showing a configuration example and a processing example of the current measurement system according to Embodiment 3. [Figure 16] It is a diagram showing a configuration example of the sensor head according to Embodiment 3. [Figure 17] It is a diagram showing Configuration Example 1-1 of the cable fixture according to Embodiment 3. [Figure 18] It is a diagram showing Configuration Example 1-2 of the cable fixture according to Embodiment 3. [Figure 19] It is a diagram showing Configuration Example 2-1 of the cable fixture according to Embodiment 3. [Figure 20] It is a diagram showing Configuration Example 2-2 of the cable fixture according to Embodiment 3. [Figure 21] It is a block diagram showing a configuration example of each device of the current measurement system according to Embodiment 3. [Figure 22] It is a diagram showing an example of the third detection data storage unit of the current measurement device according to Embodiment 3. [Figure 23] It is a diagram showing an example of the third position data storage unit of the current measurement device according to Embodiment 3. [Figure 24] It is a flowchart showing an example of the processing flow of the current measurement system according to Embodiment 3. [Figure 25] It is a diagram showing a hardware configuration example according to Embodiments 1 to 3.

Embodiments for Carrying Out the Invention

[0012] A current measurement system, current measurement device, current measurement method, and current measurement program according to one embodiment of the present invention will be described in detail below with reference to the drawings. However, the present invention is not limited to embodiments 1 to 3 described below.

[0013] [Embodiment 1] The configuration and processing of the current measurement system 100-1 according to Embodiment 1, the configuration and processing of each device in the current measurement system 100-1, the flow of each process in the current measurement system 100-1, and the effects of Embodiment 1 will be described below.

[0014] [1. Configuration and operation of current measurement system 100-1] The configuration and operation of the current measurement system 100-1 according to Embodiment 1 will be described using Figures 1 to 3. Below, an example of the overall configuration of the current measurement system 100-1, an example of the configuration of the magnetic field shield 3, an example of the configuration of the cable 9, an example of the configuration of the sensor head 1-1, an example of the operation of the current measurement system 100-1, and the effects of the current measurement system 100-1 will be described.

[0015] (1-1. Example of the overall configuration of the current measurement system 100-1) An example of the overall configuration of the current measurement system 100-1 will be explained using Figure 1. Figure 1 is a diagram showing an example of the configuration and processing of the current measurement system 100-1 according to Embodiment 1. The current measurement system 100-1 consists of a sensor head 1-1, a current measuring device 2-1, a probe 5, and a distance measuring sensor 6. Here, the sensor head 1-1, the current measuring device 2-1, the probe 5, and the distance measuring sensor 6 are connected to each other via a predetermined communication network, either by wire or wireless. Various communication networks such as the Internet or dedicated lines can be used as the predetermined communication network.

[0016] (1-1-1. Sensor head 1-1) Sensor head 1-1 is a sensor device installed on cable 9, which is the conductor to be measured, and measures the magnetic field H generated by the current I flowing through cable 9. Sensor head 1-1 is covered by a magnetic field shield 3 with a partial opening on its bottom surface, and a magnetic field sensor 4 is installed inside. Note that the current measurement system 100-1 shown in Figure 1 may include multiple sensor heads 1-1.

[0017] Here, the direction of the current I flowing through cable 9 is schematically indicated by the arrow in the figure. Current I may be a direct current or an alternating current. The frequency (fundamental frequency) of current I is called frequency f. Also, the direction of the magnetic field H generated by the current I flowing through cable 9 is schematically indicated by the arrow in the figure.

[0018] Next, we will explain the XYZ coordinate system. The Z-axis direction corresponds to the direction in which cable 9 extends. The X-axis and Y-axis directions (XY plane direction) correspond to the cross-sectional direction of cable 9. The positive and negative X-axis directions are also called the left-right direction, etc. The positive and negative Y-axis directions are also called the up-down direction, etc. The positive and negative Z-axis directions are also called the front-back direction, etc.

[0019] The magnetic field shield 3 takes in (a portion of) the magnetic field H generated by the current I flowing through the cable 9 into its internal space 30 through its opening 37. The magnetic field sensor 4 detects the magnetic field H taken in into the internal space 30 of the magnetic field shield 3 and outputs it as a sensor voltage value V1. At this time, the magnetic field sensor 4 outputs the sensor voltage value V1 to the detection circuit 51 built into the probe 5 via the terminal 38 and wiring W1 of the magnetic field shield 3.

[0020] (1-1-2. Current measuring device 2-1) The current measuring device 2-1 is a device that identifies the cable center position CC of cable 9 and measures the current I flowing through cable 9. Note that the current measuring system 100-1 shown in Figure 1 may include multiple current measuring devices 2-1. Furthermore, while the example in Figure 1 shows the current measuring device 2-1 implemented by an oscilloscope, it may also be implemented by a desktop PC (Personal Computer), notebook PC, smartphone, server device, cloud system, etc.

[0021] The current measuring device 2-1 has an input unit 21 and an output unit 22. In the example shown in Figure 1, the input unit 21 is an input terminal connected to the probe 5. The output unit 22 is a display that shows the waveform of the measured current I.

[0022] (1-1-3. Probe 5) The probe 5 is a device that is communicatively connected between the current measuring device 2-1 and the sensor head 1-1 by wiring W1, and incorporates a detection circuit 51 that converts the sensor voltage value V1 detected by the sensor head 1-1. Note that the current measuring system 100-1 shown in Figure 1 may include multiple probes 5. Furthermore, the probe 5 may be integrated with either the sensor head 1-1 or the current measuring device 2-1.

[0023] (1-1-4. Distance measuring sensor 6) The distance measuring sensors 6 (61, 62, ...) are connected to the current measuring device 2-1 via wired or wireless communication and are sensor devices that detect distance data D1 indicating the distance between the cable 9 and each distance measuring sensor 6. For example, the distance measuring sensors 6 can be implemented as radar sensors 6A or imaging sensors 6B.

[0024] (1-2. Example of Magnetic Field Shield 3 Configuration) An example of the configuration of the magnetic field shield 3 will be explained using Figure 2. Figure 2 is a diagram showing an example of the configuration of the magnetic field shield 3 according to Embodiment 1. The magnetic field shield 3 has a hollow, substantially box shape. The magnetic field shield 3 includes a bottom plate 31, a top plate 32, side plates 33, side plates 34, side plates 35, and side plates 36. The bottom plate 31, top plate 32, side plates 33, side plates 34, side plates 35, and side plates 36 define the shape of the magnetic field shield 3 such that the magnetic field shield 3 has an internal space 30 inside it and also has an opening 37.

[0025] The bottom plate 31 and the top plate 32 are located on opposite sides of each other in the vertical direction (Y-axis direction), with the internal space 30 in between, and extend opposite each other in the XZ plane direction as the plane direction. In the positive Y-axis direction, the bottom plate 31, the internal space 30, and the top plate 32 are located in this order.

[0026] Side plates 33 and 34 are located on opposite sides of the internal space 30 in the left-right direction (X-axis direction), and extend opposite each other in the YZ plane direction as the plane direction. In the positive X-axis direction, side plate 33, internal space 30, and side plate 34 are located in this order.

[0027] Side plates 35 and 36 are located on opposite sides of each other in the front-to-back direction (Z-axis direction), with the internal space 30 in between, and extend so as to face each other in the XY plane direction. Side plate 35, internal space 30, and side plate 36 are located in this order in the positive Z-axis direction.

[0028] In the example shown in Figure 2, the opening 37 is formed by cutting out parts of the bottom plate 31, the side plate 35, and the side plate 36, and extends throughout the entire length of the magnetic field shield 3 in the front-to-back direction (Z-axis direction). The area of ​​the opening 37 in the XY plane (size of the opening) is designed so that the cable 9 can pass through the opening 37.

[0029] Unless otherwise specified, "inside the magnetic field shield 3" refers to the internal space 30 of the magnetic field shield 3. Within the bounds of consistency, "inside the magnetic field shield 3" and "internal space 30" may be interpreted differently as appropriate.

[0030] (1-3. Example configuration of cable 9) The conductive cable 9 is installed in vehicles such as hybrid vehicles (HV) and electric vehicles (EV) and is used to carry currents ranging from several amperes to tens of amperes or larger. Examples of cable 9 include cables and busbars used to connect batteries and power units, or converters and inverters.

[0031] (1-4. Example configuration of sensor head 1-1) An example of the configuration of the sensor head 1-1 will be explained using Figure 3. Figure 3 is a diagram showing an example of the configuration of the sensor head 1-1 according to Embodiment 1. The sensor head 1-1 has a magnetic field shield 3 and a magnetic field sensor 4. In the example of Figure 3, the sensor head 1-1 is installed on the cable 9 so as to pass through the opening 37 at the bottom of the magnetic field sensor 4. At this time, the sensor head 1-1 may use, for example, a hook-shaped member, a ring-shaped member, etc. to attach the magnetic field shield 3 to the cable 9, or a spring member, etc. to fix the attachment. In addition, the sensor head 1-1 has the magnetic field sensor 4 built into the magnetic field shield 3 so that the magnetic field sensor 4 is located in the vertical direction of the cable 9, but the installation position of the magnetic field sensor 4 is not particularly limited. In the following, the installation position of the magnetic field sensor 4 in the XZ plane direction of the sensor head 1-1 will be described as the magnetic field sensor position MS, and the center of the cable 9 in the XY plane direction closest to the magnetic field sensor position MS will be described as the cable center position CC.

[0032] (1-5. Processing example of current measurement system 100-1) This section describes an example of the processing of the current measurement system 100-1. The following describes the distance data measurement process, distance data acquisition process, cable center position identification process, and current data calculation process. Note that the above processes can be executed in a different order. Furthermore, some of the above processes may be omitted.

[0033] (1-5-1. Distance data measurement processing) Firstly, the distance sensor 6 measures distance data D1 with respect to the cable 9. For example, distance sensor 61 measures distance data D1(1) indicating the distance between distance sensor 61 and the surface of cable 9. Also, distance sensor 62 measures distance data D1(2) indicating the distance between distance sensor 62 and the surface of cable 9.

[0034] (1-5-2. Distance data acquisition process) Secondly, the current measuring device 2-1 acquires distance data D1 from the distance measuring sensor 6. For example, the current measuring device 2-1 acquires distance data D1(1) measured by the distance measuring sensor 61. The current measuring device 2-1 also acquires distance data D1(2) measured by the distance measuring sensor 62.

[0035] (1-5-3. Cable center position identification process) Thirdly, the current measuring device 2-1 identifies the cable center position CC of the cable 9. For example, the current measuring device 2-1 identifies the cable center position CC of the cable 9 using distance data D1(1), D1(2), ... obtained from multiple distance measuring sensors 6 (61, 62, ...). At this time, the current measuring device 2-1 further identifies the cable center position CC using the set values ​​of the distance measuring sensor 6's distance measuring sensor position DS, the magnetic field sensor position MS of the magnetic field sensor 4, and the cable radius d of the cable 9.

[0036] (1-5-4. Current Data Calculation Process) Fourth, the current measuring device 2-1 calculates current data A of the current I flowing through the cable 9. For example, the current measuring device 2-1 uses the cable center position CC of the identified cable 9 and the magnetic field data M obtained from the magnetic field sensor 4 to calculate current data A, which indicates the current value (A) of the current I flowing through the cable 9 at regular intervals.

[0037] (1-6. Effects of the 100-1 Current Measurement System) After describing the outline of the current measurement system 100-1 according to Embodiment 1, the effects of the current measurement system 100-1 will be explained.

[0038] (1-6-1. Overview of Current Measurement System 100-1) An overview of the current measurement system 100-1 according to Embodiment 1 will be described. The current measurement system 100-1 performs the following processes. First, the distance sensor 6 measures distance data D1 indicating the distance to the cable 9. Second, the current measurement device 2-1 acquires the distance data D1 from the distance sensor 6. Third, the current measurement device 2-1 uses the distance data D1 to identify the cable center position CC of the cable 9. Fourth, the current measurement device 2-1 uses the cable center position CC and magnetic field data M to calculate current data A indicating the current value (A) of the current I flowing through the cable 9.

[0039] (1-6-2. Effects of the current measurement system 100-1) The effects of the current measurement system 100-1 according to Embodiment 1 will now be described. The current measurement system 100-1 collects distance data D1 to the cable 9 using distance measuring sensors 6 such as a radar sensor 6A and an imaging sensor 6B installed outside the sensor head 1-1, and accurately identifies the cable center position CC for calculating the current value (A) of the current I flowing through the cable 9. Therefore, the current measurement system 100-1 can improve the measurement accuracy of the current I flowing through the cable 9.

[0040] [2. Configuration and operation of each device in the current measurement system 100-1] Using Figures 4 to 7, the configuration and processing of each device in the current measurement system 100-1 shown in Figure 1 will be explained. Below, an example of the overall configuration of the current measurement system 100-1 according to Embodiment 1, an example of the configuration and processing of the sensor head 1-1, an example of the configuration and processing of the current measurement device 2-1, an example of the configuration and processing of the probe 5, and an example of the configuration and processing of the distance measuring sensor 6 will be explained.

[0041] (2-1. Example of the overall configuration of the current measurement system 100-1) Using Figure 4, an example of the overall configuration of the current measurement system 100-1 shown in Figure 1 will be explained. Figure 4 is a block diagram showing an example of the configuration of each device in the current measurement system 100-1 according to Embodiment 1. As shown in Figure 4, the current measurement system 100-1 consists of a sensor head 1-1, a current measuring device 2-1, a probe 5, and a distance measuring sensor 6. The sensor head 1-1 and the current measuring device 2-1 are connected via the probe 5 so as to be able to communicate using a dedicated line or the like. The current measuring device 2-1 and the distance measuring sensor 6 are connected so as to be able to communicate using a communication network N, which is implemented via the internet or a dedicated line or the like.

[0042] (2-2. Example configuration and processing of sensor head 1-1) Using Figure 4, an example of the configuration and processing of the sensor head 1-1 will be explained. As shown in Figure 4, the sensor head 1-1 consists of a magnetic field shield 3 and a magnetic field sensor 4, and is installed on a cable 9 which is a conductor.

[0043] (2-2-1. Magnetic field shielding 3) The magnetic field shield 3 is configured to take in the magnetic field H generated by the current I flowing through the cable 9. The magnetic field shield 3 is also configured to shield the magnetic field H. The magnetic field shield 3 may be made of various known materials, including metallic materials.

[0044] (2-2-2. Magnetic field sensor 4) The magnetic field sensor is installed inside the magnetic field shield 3. The magnetic field sensor 4 detects the magnetic field H at the installation location, magnetic field sensor position MS. For example, the magnetic field sensor 4 is an integrated circuit (IC) sensor that includes a Hall element, and is also called an analog Hall IC. Alternatively, the magnetic field sensor 4 may be a coil sensor that includes a coil. In this case, a Rogowski coil may be used for the magnetic field sensor 4, and because it can be miniaturized, it becomes easier to place the magnetic field sensor 4 inside the magnetic field shield 3.

[0045] (2-3. Example configuration and processing of current measuring device 2-1) Using Figure 4, an example of the configuration and processing of the current measuring device 2-1 will be explained. As shown in Figure 4, the current measuring device 2-1 is composed of an input unit 21, an output unit 22, a communication unit 23, a storage unit 24-1, and a control unit 25.

[0046] (2-3-1. Input section 21) The input unit 21 is responsible for inputting various types of information to the current measuring device 2-1. For example, the input unit 21 is implemented using input terminals, etc., and accepts various types of information input to the current measuring device 2-1.

[0047] (2-3-2. Output section 22) The output unit 22 is responsible for outputting various types of information from the current measuring device 2-1. For example, the output unit 22 is implemented as a display or the like and displays various types of information stored in the current measuring device 2-1.

[0048] (2-3-3. Communications Section 23) The communication unit 23 is responsible for data communication with other devices. For example, the communication unit 23 performs data communication with each communication device via a router or the like. The communication unit 23 can also perform data communication with terminals (not shown).

[0049] (2-3-4. Storage section 24-1) The storage unit 24-1 stores various information that the control unit 25 refers to when it operates, and various information acquired when the control unit 25 operates. The storage unit 24-1 is composed of a first detection data storage unit 24a-1, a first position data storage unit 24b-1, and a current data storage unit 24c. Here, the storage unit 24-1 can be implemented as, for example, a semiconductor memory element such as RAM (Random Access Memory) or flash memory, or a storage device such as a hard disk or optical disc. In the example in Figure 4, the storage unit 24-1 is installed inside the current measuring device 2-1, but it may be installed outside the current measuring device 2-1, or multiple storage units may be installed.

[0050] (2-3-4-1. First detection data storage unit 24a-1) The first detection data storage unit 24a-1 stores the first detection data. For example, the first detection data storage unit 24a-1 stores distance data D1 as the first detection data, which corresponds to the sensor value detected by the distance measuring sensor 6 and is acquired by the acquisition unit 25a of the control unit 25, which will be described later. Here, an example of the data stored by the first detection data storage unit 24a-1 will be explained using Figure 5. Figure 5 is a diagram showing an example of the first detection data storage unit 24a-1 of the current measuring device 2-1 according to Embodiment 1. In the example in Figure 5, the first detection data storage unit 24a-1 has items such as "sensor head", "cable", "distance measuring sensor", and "distance".

[0051] "Sensor head" refers to identification information for identifying sensor head 1-1, such as the identification number or identification symbol of sensor head 1-1. "Cable" refers to identification information for identifying cable 9, which is the conductor to be measured, such as the identification number or identification symbol of cable 9 on which sensor head 1-1 is installed. "Distance measuring sensor" refers to identification information for identifying distance measuring sensor 6, such as the identification number or identification symbol of distance measuring sensor 6. "Distance" is distance data D1 between distance measuring sensor 6 and the surface of cable 9, expressed in millimeters (mm), centimeters (cm), meters (m), etc.

[0052] In other words, Figure 5 shows an example in which data such as distance data D1 being {distance sensor: "DS001", distance: "D001-DS"}, {distance sensor: "DS002", distance: "D002-DS"}, {distance sensor: "DS003", distance: "D003-DS"}, etc., is stored in the first detection data storage unit 24a-1 for the sensor head 1-1 identified by "H001" and the cable 9 identified by "C001".

[0053] (2-3-4-2. First position data storage unit 24b-1) The first position data storage unit 24b-1 stores first position data. For example, the first position data storage unit 24b-1 stores position data L1 indicating the cable center position CC of cable 9, which has been identified from distance data D1 by the identification unit 25b of the control unit 25, which will be described later. Here, an example of the data stored by the first position data storage unit 24b-1 will be explained using Figure 6. Figure 6 is a diagram showing an example of the first position data storage unit 24b-1 of the current measuring device 2-1 according to Embodiment 1. In the example in Figure 6, the first position data storage unit 24b-1 has items such as "sensor head", "cable", and "center position".

[0054] "Sensor head" indicates identification information for identifying sensor head 1-1, such as the identification number or identification symbol of sensor head 1-1. "Cable" indicates identification information for identifying cable 9, which is the conductor to be measured, such as the identification number or identification symbol of cable 9 on which sensor head 1-1 is installed. "Center position" is position data L1 indicating the center position CC of cable 9, which is represented by the 3D coordinates of the point that passes through the center of the cylindrical cable 9 and is closest to the magnetic field sensor position MS of magnetic field sensor 4, or the distance r from the magnetic field sensor position MS.

[0055] In other words, Figure 6 shows an example in which data such as position data L1 being {center position: "CC001-DS"} is stored in the first position data storage unit 24b-1 for the sensor head 1-1 identified by "H001" and the cable 9 identified by "C001".

[0056] (2-3-4-3. Current data storage unit 24c) The current data storage unit 24c stores current data A. For example, the current data storage unit 24c stores current data A that indicates the current value (A) calculated by the calculation unit 25c of the control unit 25, which will be described later. Here, an example of the data stored by the current data storage unit 24c will be explained using Figure 7. Figure 7 is a diagram showing an example of the current data storage unit 24c of the current measuring device 2-1 according to Embodiment 1. In the example in Figure 7, the current data storage unit 24c has items such as "sensor head", "cable", "time", "magnetic field", and "current".

[0057] "Sensor head" indicates identification information for identifying sensor head 1-1, such as the identification number or symbol of sensor head 1-1. "Cable" indicates identification information for identifying cable 9, which is the conductor to be measured, such as the identification number or symbol of cable 9 on which sensor head 1-1 is installed. "Time" indicates the time when the current data A was output, such as year, month, day, hour, minute, and second. "Magnetic field" indicates the strength of the magnetic field H generated by the current I flowing through cable 9, such as amperes per meter (A / m). "Current" indicates the strength of the current I flowing through cable 9, such as amperes (A).

[0058] In other words, Figure 7 shows an example in which data such as {time: "T001", magnetic field: "M001", current: "A001"}, {time: "T002", magnetic field: "M002", current: "A002"}, {time: "T003", magnetic field: "M003", current: "A003"}, ... is stored in the current data storage unit 24c for the sensor head 1-1 identified by "H001" and the cable 9 identified by "C001".

[0059] (2-3-5. Control Unit 25) The control unit 25 is responsible for controlling the entire current measuring device 2-1. The control unit 25 consists of an acquisition unit 25a, a specification unit 25b, and a calculation unit 25c. Here, the control unit 25 can be implemented by electronic circuits such as a CPU (Central Processing Unit) or an MPU (Micro Processing Unit), or by integrated circuits such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

[0060] (2-3-5-1. Acquisition part 25a) The acquisition unit 25a acquires various types of information. The acquisition unit 25a may also store the acquired information in the storage unit 24-1. The magnetic field data acquisition process and the first detection data acquisition process will be described below.

[0061] (Magnetic field data acquisition process) The acquisition unit 25a performs magnetic field data acquisition processing. For example, the acquisition unit 25a acquires the detection result of the magnetic field sensor 4. At this time, the acquisition unit 25a acquires the magnetic field strength (A / m) converted by the probe 5 according to the sensor voltage value V1 detected by the magnetic field sensor 4 at the magnetic field sensor position MS, etc., as the detection result magnetic field data M.

[0062] A specific example of the magnetic field data acquisition process will be described. Firstly, the acquisition unit 25a acquires magnetic field data M, which is detected by the magnetic field sensor 4 identified by "MS001" and converted by the probe 5, for the sensor head 1-1 identified by "H001" and the cable 9 identified by "C001", and for the magnetic field sensor 4 identified by "MS001", and converted by the probe 5, as {time: "T001", magnetic field: "M001"}, {time: "T002", magnetic field: "M002"}, {time: "T003", magnetic field: "M003"}, ... Secondly, the acquisition unit 25a stores the acquired magnetic field data M in the current data storage unit 24c.

[0063] Furthermore, the acquisition unit 25a can acquire the sensor voltage value V1 detected by the magnetic field sensor 4 as magnetic field data M and store it in the current data storage unit 24c. Alternatively, the acquisition unit 25a can acquire the sensor voltage value V1 detected by the magnetic field sensor 4 as magnetic field data M, convert the acquired sensor voltage value V1 into magnetic field strength (A / m), and store the converted magnetic field strength (A / m) in the current data storage unit 24c.

[0064] (First detection data acquisition process) The acquisition unit 25a executes a first detection data acquisition process. For example, the acquisition unit 25a acquires the detection result of a predetermined sensor. At this time, the acquisition unit 25a acquires first detection data as a detection result, corresponding to the sensor value of the predetermined sensor with respect to the position where the conductor cable 9 is installed. At this time, the acquisition unit 25a assumes that the predetermined sensor is a distance measuring sensor 6 that measures the distance of the cable 9, and acquires multiple distance data D1 as first detection data, indicating the distance from each of the multiple distance measuring sensors 6 to the cable 9, according to the sensor values ​​of the multiple distance measuring sensors 6. Alternatively, the acquisition unit 25a assumes that the distance measuring sensor 6 is a radar sensor 6A, and acquires multiple distance data D1 as first detection data, indicating the distance from each of the multiple radar sensors 6A to the cable 9, according to the sensor values ​​of the multiple radar sensors 6A. Alternatively, the acquisition unit 25a assumes that the distance measuring sensor 6 is an imaging sensor 6B that images the cable 9, and acquires multiple distance data D1 as first detection data, indicating the distance (m) from each of the multiple imaging sensors 6B to the cable 9, according to the sensor values ​​of the multiple imaging sensors 6B.

[0065] A specific example of the first detection data acquisition process will now be described. Firstly, the acquisition unit 25a acquires "D001-DS" as distance data D1(1) detected by the distance measuring sensor 61 identified by "DS001" for the sensor head 1-1 identified by "H001" and the cable 9 identified by "C001", acquires "D002-DS" as distance data D1(2) detected by the distance measuring sensor 6-2 identified by "DS002", and acquires "D003-DS" as distance data D1(3) detected by the distance measuring sensor 6-3 identified by "DS003". Secondly, the acquisition unit 25a stores the acquired distance data D1(1), D1(2), and D1(3) in the first detection data storage unit 24a-1.

[0066] The acquisition unit 25a can also acquire the sensor value detected by the distance measuring sensor 6 as distance data D1, convert the acquired sensor value into distance (m), and store the converted distance (m) in the first detection data storage unit 24a-1.

[0067] (2-3-5-2. Specific part 25b) The identification unit 25b identifies various types of information. The identification unit 25b may also store the identified information in the storage unit 24-1. The position data output process will be described below.

[0068] (Location data output processing) The identification unit 25b performs position data output processing. For example, it identifies the cable center distance CC of the conductor cable 9 based on the detection results of a predetermined sensor that has been acquired. At this time, the identification unit 25b identifies the cable center position CC of the cable 9 based on the first detection data, which is the detection result. The identification unit 25b also identifies the cable center position CC of the cable 9 using a plurality of distance data D1 that have been acquired.

[0069] A specific example of the position data output processing will be described. Firstly, the identification unit 25b refers to the distance data D1, which is {distance sensor: "DS001", distance: "D001-DS"}, {distance sensor: "DS002", distance: "D002-DS"}, {distance sensor: "DS003", distance: "D003-DS"}, ... for the sensor head 1-1 identified by "H001" and the cable 9 identified by "C001", as first detection data stored in the first detection data storage unit 24a-1. Secondly, the identification unit 25b refers to the cable radius d of the cable 9, "CD001", the magnetic field sensor position MS of the magnetic field sensor 4, and the distance sensor position DS of the distance sensor 6, "L001-DS", "L002-DS", "L003-DS", ... as setting values ​​to be stored in the storage unit 24-1 for the sensor head 1-1 identified by "H001" and the cable 9 identified by "C001". Thirdly, the identification unit 25b outputs position data L1, which is {center position: "CC001-DS"}, using the distance data D1, cable radius d, magnetic field sensor position MS of the magnetic field sensor 4, and distance sensor position DS of the distance sensor 6 for the sensor head 1-1 identified by "H001" and the cable 9 identified by "C001". Fourthly, the identification unit 25b stores the output position data L1 in the first position data storage unit 24b-1.

[0070] (2-3-5-3. Calculation part 25c) The calculation unit 25c acquires various information. The calculation unit 25c may also store the calculated information in the storage unit 24-1. The current data calculation process will be described below.

[0071] (Current data calculation process) The calculation unit 25c performs current data calculation processing. For example, the calculation unit 25c calculates the current value (A) of the current I flowing through the cable 9 as current data A, based on the cable center position CC of the cable 9, which is the identified conductor, and the detection result obtained from the magnetic field sensor 4.

[0072] A specific example of the current data calculation process will be explained. Firstly, the calculation unit 25c refers to the position data L1, which is {center position: "CC001-DS"}, as the first position data stored in the first position data storage unit 24b-1 for the sensor head 1-1 identified by "H001" and the cable 9 identified by "C001", and determines the distance r (m) from the magnetic field sensor position MS of the magnetic field sensor 4 to the cable center position CC. Secondly, the calculation unit 25c obtains the magnetic field data M, which is {time: "T001", magnetic field: "M001"}, {time: "T002", magnetic field: "M002"}, {time: "T003", magnetic field: "M003"}, ..., stored in the current data storage unit 24c for the sensor head 1-1 identified by "H001" and the cable 9 identified by "C001". Thirdly, the calculation unit 25c calculates current data A, such as {time: "T001", current: "A001"}, {time: "T002", current: "A002"}, {time: "T003", current: "A003"}, ... by substituting the distance r (m) and the magnetic field strength (A / m) indicated by the magnetic field data M into the formula H = I / (2πr) derived from Ampère's law. Fourthly, the calculation unit 25c stores the calculated current data A in the current data storage unit 24c.

[0073] (2-4. Example configuration and processing of Probe 5) Using Figure 4, an example of the configuration and processing of probe 5 will be explained. Probe 5 includes a detection circuit 51 and converts the detection result of the magnetic field sensor 4. For example, probe 5 converts the sensor voltage value V1 detected by the magnetic field sensor 4 into magnetic field strength (A / m).

[0074] (2-5. Example configuration and processing of the distance measuring sensor 6) Using Figure 4, an example of the configuration and processing of the distance measuring sensor 6 will be explained. The distance measuring sensor 6 is an example of a predetermined sensor that detects a conductor cable 9. For example, the distance measuring sensor 6 measures the distance of the cable 9. In this case, the distance measuring sensor 6 includes a radar sensor 6A. The distance measuring sensor 6 also includes an imaging sensor 6B that images the cable 9.

[0075] [3. Flow of each process in the current measurement system 100-1] The processing flow of the current measurement system 100-1 according to Embodiment 1 will be explained using Figure 8. Figure 8 is a flowchart showing an example of the processing flow of the current measurement system 100-1 according to Embodiment 1. Note that the processes in steps S101 to S110 below can be executed in a different order. Also, some of the processes in steps S101 to S110 below may be omitted.

[0076] (3-1. First detection data measurement process) Firstly, the current measurement system 100-1 performs a first detection data measurement process (step S101). For example, the distance measuring sensor 61 outputs distance data D1(1) as first detection data, which indicates the distance from the distance measuring sensor 61 to the surface of the cable 9. The distance measuring sensor 62 also outputs distance data D1(2) as first detection data, which indicates the distance from the distance measuring sensor 62 to the surface of the cable 9.

[0077] (3-2. First detection data acquisition process) Secondly, the current measuring system 100-1 performs a first detection data acquisition process (step S102). For example, the current measuring device 2-1 acquires distance data D1(1) from the distance measuring sensor 61 as first detection data. The current measuring device 2-1 also acquires distance data D1(2) from the distance measuring sensor 62 as first detection data.

[0078] (3-3. First detection data storage process) Thirdly, the current measurement system 100-1 performs a first detection data storage process (step S103). For example, the current measurement device 2-1 stores the distance data D1(1) acquired from the distance measuring sensor 61 and the distance data D1(2) acquired from the distance measuring sensor 62 as first detection data in the first detection data storage unit 24a-1.

[0079] (3-4. First detection data reference processing) Fourth, the current measuring system 100-1 performs a first detection data reference process (step S104). For example, the current measuring device 2-1 refers to the distance data D1(1) and distance data D1(2) stored in the first detection data storage unit 24a-1 as the first detection data. The current measuring device 2-1 also refers to the cable radius d of the cable 9, which is a set value stored in the storage unit 24-1. The current measuring device 2-1 also refers to the magnetic field sensor position MS of the magnetic field sensor 4, which is a set value stored in the storage unit 24-1. The current measuring device 2-1 also refers to the distance sensor position DS-1 of the distance sensor 61 and the distance sensor position DS-2 of the distance sensor 62, which are set values ​​stored in the storage unit 24-1.

[0080] (3-5. First position data calculation process) Fifth, the current measurement system 100-1 performs a first position data calculation process (step S105). For example, the current measurement device 2-1 uses distance data D1(1), distance data D1(2), cable radius d, magnetic field sensor position MS, distance measuring sensor position DS-1, and distance measuring sensor position DS-2 as first position data to calculate position data L1 indicating the cable center position CC of cable 9.

[0081] (3-6. First position data storage process) Sixth, the current measurement system 100-1 performs a first position data storage process (step S106). For example, the current measurement device 2-1 stores position data L1, which includes the calculated three-dimensional coordinates of the cable center position CC and the distance r from the magnetic field sensor position MS, as first position data in the first position data storage unit 24b-1.

[0082] (3-7. First position data reference processing) Seventh, the current measuring system 100-1 performs a first position data reference process (step S107). For example, the current measuring device 2-1 references the position data L1 stored in the first position data storage unit 24b-1 as the first position data.

[0083] (3-8. Magnetic field data reference processing) Eighth, the current measurement system 100-1 performs magnetic field data reference processing (step S108). For example, the current measurement device 2-1 references the magnetic field data M measured by the magnetic field sensor 4 and stored in the current data storage unit 24c.

[0084] (3-9. Current Data Calculation Process) Ninth, the current measurement system 100-1 performs current data calculation processing (step S109). For example, the current measurement device 2-1 uses position data L1 and magnetic field data M to calculate current data A, which indicates the current value (A) of the current I flowing through the cable 9 at regular intervals.

[0085] (3-10. Current Data Storage Process) Tenth, the current measurement system 100-1 performs current data storage processing (step S110) and terminates the process. For example, the current measurement device 2-1 stores the calculated current data A in the current data storage unit 24c. At this time, the current measurement device 2-1 can also display the calculated current data A as a waveform of current I on the output unit 22, which is a display.

[0086] [4. Effects of Embodiment 1] The effects of Embodiment 1 will be described below. Effects 1 to 3 corresponding to the processing of Embodiment 1 will be described below.

[0087] (4-1. Effect 1) Firstly, in the process according to Embodiment 1 described above, the current measurement system 100-1 includes a magnetic field shield 3 configured to take in the magnetic field H generated by the current I flowing through the cable 9, a magnetic field sensor 4 installed inside the magnetic field shield 3, a distance measuring sensor 6 for measuring the distance of the cable 9, and a current measurement device 2-1. The current measurement device 2-1 acquires the detection results of the distance measuring sensor 6 and the detection results of the magnetic field sensor 4, identifies the cable center position CC of the cable 9 based on the acquired detection results of the distance measuring sensor 6, and calculates the current value (A) of the current I flowing through the cable 9 based on the identified cable center position CC and the acquired detection results of the magnetic field sensor 4. Therefore, in this process, by using the distance measuring sensor 6 as a predetermined sensor for detecting the cable 9, the measurement accuracy of the current I flowing through the cable 9 can be improved.

[0088] (4-2. Effect 2) Secondly, in the process according to Embodiment 1 described above, the distance measuring sensor 6 includes a radar sensor 6A. Therefore, in this process, by using the radar sensor 6A as a predetermined sensor for detecting the cable 9, the measurement accuracy of the current I flowing through the cable 9 can be improved.

[0089] (4-3. Effect 3) Thirdly, in the process according to Embodiment 1 described above, the distance measuring sensor 6 includes an imaging sensor 6B that images the cable 9. Therefore, in this process, by using the imaging sensor 6B as a predetermined sensor for detecting the cable 9, the measurement accuracy of the current I flowing through the cable 9 can be improved.

[0090] [Embodiment 2] The configuration and processing of the current measurement system 100-2 according to Embodiment 2, the configuration and processing of each device in the current measurement system 100-2, the flow of each process in the current measurement system 100-2, and the effects of the embodiment will be described below. Note that configurations and processes common to Embodiment 1 will not be described.

[0091] [1. Configuration and operation of current measurement system 100-2] Using Figure 9, the configuration and processing of the current measurement system 100-2 according to Embodiment 2 will be described. Below, an example of the overall configuration of the current measurement system 100-2, an example of the configuration of the sensor head 1-2, an example of the processing of the current measurement system 100-2, and the effects of the current measurement system 100-2 will be described. Note that the example configuration of the magnetic field shield 3 and the example configuration of the cable 9 are the same as in Embodiment 1, so their explanation will be omitted.

[0092] (1-1. Example of the overall configuration of the current measurement system 100-2) Figure 9 illustrates an example of the overall configuration of the current measurement system 100-2. The current measurement system 100-2 consists of a sensor head 1-2, a current measuring device 2-2, and a probe 5. Figure 9 is a diagram showing an example of the configuration and processing of the current measurement system 100-2 according to Embodiment 2. Here, the sensor head 1-2, the current measuring device 2-2, and the probe 5 are connected to each other via a predetermined communication network, either by wire or wireless communication. Various communication networks such as the Internet or dedicated lines can be used as the predetermined communication network.

[0093] (1-1-1. Sensor head 1-2) Sensor heads 1-2 are sensor devices installed on a cable 9, which is the conductor to be measured, and measure the magnetic field H generated by the current I flowing through the cable 9. Sensor heads 1-2 are covered by a magnetic field shield 3 with a partial opening on the bottom surface, and multiple magnetic field sensors 4 (41, 42) are installed inside. Note that the current measurement system 100-2 shown in Figure 9 may include multiple sensor heads 1-2. Note that the direction of the current I, the direction of the magnetic field, and the XYZ coordinate system are the same as in Embodiment 1, so their explanation will be omitted.

[0094] The magnetic field shield 3 takes in (a portion of) the magnetic field H generated by the current I flowing through the cable 9 into its internal space 30 through its opening 37. The magnetic field sensor 41 detects the magnetic field H taken in into the internal space 30 of the magnetic field shield 3 and outputs it as a sensor voltage value V1. The magnetic field sensor 42 also detects the magnetic field H taken in into the internal space 30 of the magnetic field shield 3 and outputs it as a sensor voltage value V2. At this time, the magnetic field sensor 4 outputs the sensor voltage values ​​V1 and V2 to the detection circuit 51 built into the probe 5 via the terminal 38 and wiring W1 of the magnetic field shield 3.

[0095] (1-1-2. Current measuring device 2-2) The current measuring device 2-2 is a device that identifies the cable center position CC of cable 9 and measures the current I flowing through cable 9. Note that the current measuring system 100-2 shown in Figure 9 may include multiple current measuring devices 2-2. Furthermore, while the example in Figure 9 shows the current measuring device 2-2 being implemented using an oscilloscope, it may also be implemented using a desktop PC, notebook PC, smartphone, server device, cloud system, etc.

[0096] The current measuring device 2-2 has an input unit 21 and an output unit 22. In the example shown in Figure 9, the input unit 21 is an input terminal connected to the probe 5. The output unit 22 is a display that shows the waveform of the measured current I.

[0097] (1-1-3. Probe 5) The probe 5 is a device that is communicatively connected between the sensor head 1-2 and the current measuring device 2-2 by wiring W1, and incorporates a detection circuit 51 that converts the sensor voltage values ​​V1 and V2 detected by the sensor head 1-2. Note that the current measuring system 100-2 shown in Figure 9 may include multiple probes 5. Furthermore, the probe 5 may be integrated with the current measuring device 2-2 or the sensor head 1-2.

[0098] (1-2. Example configuration of sensor head 1-2) An example of the configuration of the sensor head 1-2 will be explained using Figure 10. Figure 10 is a diagram showing an example of the configuration of the sensor head 1-2 according to Embodiment 2. The sensor head 1-2 has a magnetic field shield 3, a magnetic field sensor 41, and a magnetic field sensor 42. In the example of Figure 10, the sensor head 1-2 is installed on the cable 9 so as to pass through the opening 37 at the bottom of the magnetic field sensor 4. At this time, the sensor head 1-2 may use, for example, a hook-shaped member, a ring-shaped member, etc. for attaching the magnetic field shield 3 to the cable 9, or a spring member, etc. for fixing the attachment. Furthermore, the sensor head 1-2 may have the magnetic field sensor 41 built into the magnetic field shield 3 so that the magnetic field sensor 41 is located in the vertical direction of the cable 9, or the magnetic field sensor 42 may be built into the magnetic field shield 3 so that the magnetic field sensor 42 is located offset from the vertical direction of the cable 9, and the installation position of the magnetic field sensor 4 is not particularly limited. In the following description, the installation position of magnetic field sensor 41 in the XZ plane direction of sensor head 1-2 will be referred to as magnetic field sensor position MS-1, and the installation position of magnetic field sensor 42 will be referred to as magnetic field sensor position MS-2. Furthermore, the center of cable 9 in the XY plane direction closest to magnetic field sensor position MS-1 or magnetic field sensor position MS-2 will be referred to as cable center position CC.

[0099] (1-3. Processing example of current measurement system 100-2) This section describes an example of the current measurement system 100-2's processing. The following describes the distance data measurement process, distance data acquisition process, cable center position identification process, and current data calculation process. Note that the above processes can be executed in a different order. Furthermore, some of the above processes may be omitted.

[0100] (1-3-1. Distance data measurement processing) Firstly, the sensor head 1-2 measures distance data D2 with respect to the cable 9. At this time, the sensor head 1-2 measures distance data D2 indicating the distance between the magnetic field sensor position MS and the cable center position CC, corresponding to the magnetic field data M detected by the magnetic field sensor 4. For example, the sensor head 1-2 converts the sensor voltage value V1 detected by the magnetic field sensor 41 into the detection circuit 51 of the probe 5 and outputs distance data D2(1) indicating the distance between the magnetic field sensor position MS-1 and the cable center position CC of the cable 9. The sensor head 1-2 also converts the sensor voltage value V2 detected by the magnetic field sensor 42 into the detection circuit 51 of the probe 5 and outputs distance data D2(2) indicating the distance between the magnetic field sensor position MS-2 and the cable center position CC of the cable 9.

[0101] (1-3-2. Distance data acquisition process) Secondly, the current measuring device 2-2 acquires distance data D2 from the sensor head 1-2. For example, the current measuring device 2-2 acquires distance data D2(1) corresponding to the detection result of the magnetic field sensor 41 via the probe 5 from the sensor head 1-2. The current measuring device 2-2 also acquires distance data D2(2) corresponding to the detection result of the magnetic field sensor 42 via the probe 5 from the sensor head 1-2.

[0102] (1-3-3. Cable center position identification process) Thirdly, the current measuring device 2-2 identifies the cable center position CC of the cable 9. For example, the current measuring device 2-2 identifies the cable center position CC of the cable 9 using distance data D2(1) corresponding to the detection result of the magnetic field sensor 41 and D2(2) corresponding to the detection result of the magnetic field sensor 42. At this time, the current measuring device 2-2 further identifies the cable center position CC using the set values ​​of the magnetic field sensor position MS-1 of the magnetic field sensor 41 and the magnetic field sensor position MS-2 of the magnetic field sensor 42.

[0103] (1-3-4. Current Data Calculation Process) Fourth, the current measuring device 2-2 calculates current data A of the current I flowing through the cable 9. For example, the current measuring device 2-2 uses the cable center position CC of the identified cable 9, the magnetic field sensor position MS of the magnetic field sensor 4 (which is a set value), and the magnetic field data M acquired from the magnetic field sensor 4 to calculate current data A, which indicates the current value (A) of the current I flowing through the cable 9 at regular intervals. At this time, the current measuring device 2-2 can calculate the current data A using magnetic field data M acquired from any of the multiple magnetic field sensors 4 (41, 42).

[0104] (1-4. Effects of the 100-2 Current Measurement System) After describing the outline of the current measurement system 100-2 according to Embodiment 2, the effects of the current measurement system 100-2 will be explained.

[0105] (1-4-1. Overview of Current Measurement System 100-2) An overview of the current measurement system 100-2 according to Embodiment 2 will be described. The current measurement system 100-2 performs the following processes. First, the sensor head 1-2 measures distance data D2 indicating the distance to the cable 9 via a plurality of magnetic field sensors 4 (41, 42, ...). Second, the current measurement device 2-2 acquires the distance data D2 from the sensor head 1-2. Third, the current measurement device 2-2 identifies the cable center position CC of the cable 9 using the distance data D2. Fourth, the current measurement device 2-2 calculates current data A indicating the current value (A) of the current I flowing through the cable 9 using the cable center position CC and magnetic field data M.

[0106] (1-4-2. Effects of the current measurement system 100-2) The effects of the current measurement system 100-2 according to Embodiment 2 will now be described. The current measurement system 100-2 collects distance data D2 to the cable 9 using multiple magnetic field sensors 4 installed inside the sensor head 1-2, and accurately identifies the cable center position CC for calculating the current value (A) of the current I flowing through the cable 9. Therefore, the current measurement system 100-2 can improve the measurement accuracy of the current I flowing through the cable 9.

[0107] [2. Configuration and operation of each device in the current measurement system 100-2] Using Figures 11 to 13, the configuration and processing of each device in the current measurement system 100-2 shown in Figure 10 will be explained. Below, an example of the overall configuration of the current measurement system 100-2 according to Embodiment 2, an example of the configuration and processing of the sensor head 1-2, an example of the configuration and processing of the current measurement device 2-2, and an example of the configuration and processing of the probe 5 will be explained.

[0108] (2-1. Example of the overall configuration of the current measurement system 100-2) Using Figure 11, an example of the overall configuration of the current measurement system 100-2 shown in Figure 10 will be explained. Figure 11 is a block diagram showing an example of the configuration of each device in the current measurement system 100-2 according to Embodiment 2. As shown in Figure 11, the current measurement system 100-2 consists of a sensor head 1-2, a current measuring device 2-2, and a probe 5. The sensor head 1-2 and the current measuring device 2-2 are connected via the probe 5 so as to be able to communicate using a dedicated line or the like. The current measuring device 2-2 is also connected so as to be able to communicate using a communication network N, which is implemented via the internet or a dedicated line or the like.

[0109] (2-2. Example configuration and processing of sensor head 1-2) Using Figure 11, an example of the configuration and processing of the sensor head 1-2 will be explained. As shown in Figure 11, the sensor head 1-2 is composed of a magnetic field shield 3 and a plurality of magnetic field sensors 4 (41, 42, ...), and is installed on a cable 9 which is a conductor.

[0110] (2-2-1. Magnetic field shielding 3) The magnetic field shield 3 is configured to take in the magnetic field H generated by the current I flowing through the cable 9. The magnetic field shield 3 is also configured to shield the magnetic field H. The magnetic field shield 3 may be made of various known materials, including metallic materials.

[0111] (2-2-2. Magnetic field sensor 4) The magnetic field sensor 4 is an example of a predetermined sensor that detects the cable 9. The magnetic field sensor 4 is installed inside the magnetic field shield 3. The magnetic field sensor 4 detects the magnetic field H at the installation location, magnetic field sensor position MS. The magnetic field sensor 4 is a plurality of magnetic field sensors 4 (41, 42, ...) installed at different locations. For example, the magnetic field sensor 4 is an IC sensor that includes a Hall element, and is also called an analog Hall IC. The magnetic field sensor 4 may also be a coil sensor that includes a coil. In this case, the magnetic field sensor 4 may be a Rogowski coil, which can be miniaturized and therefore easier to arrange inside the magnetic field shield 3.

[0112] (2-3. Example configuration and processing of current measuring device 2-2) Using Figure 11, an example of the configuration and processing of the current measuring device 2-2 will be explained. As shown in Figure 11, the current measuring device 2-2 is composed of an input unit 21, an output unit 22, a communication unit 23, a storage unit 24-2, and a control unit 25. Note that the input unit 21, output unit 22, and communication unit 23 are the same as in Embodiment 1, so their explanation will be omitted.

[0113] (2-3-1. Storage section 24-2) The storage unit 24-2 stores various information that the control unit 25 refers to when it operates, and various information acquired when the control unit 25 operates. The storage unit 24-2 includes a second detection data storage unit 24a-2, a second position data storage unit 24b-2, and a current data storage unit 24c. Here, the storage unit 24-2 can be implemented as, for example, a semiconductor memory element such as RAM or flash memory, or a storage device such as a hard disk or optical disc. In the example in Figure 11, the storage unit 24-2 is installed inside the current measuring device 2-2, but it may be installed outside the current measuring device 2-2, or multiple storage units may be installed. Furthermore, the current data storage unit 24c is the same as in Embodiment 1, so its explanation is omitted.

[0114] (2-3-1-1. Second detection data storage unit 24a-2) The second detection data storage unit 24a-2 stores the second detection data. For example, the second detection data storage unit 24a-2 stores distance data D2, which corresponds to the sensor value detected by the magnetic field sensor 4 and is acquired by the acquisition unit 25a of the control unit 25 (described later), as the second detection data. Here, an example of the data stored by the second detection data storage unit 24a-2 will be explained using Figure 12. Figure 12 is a diagram showing an example of the second detection data storage unit 24a-2 of the current measuring device 2-2 according to Embodiment 2. In the example in Figure 12, the second detection data storage unit 24a-2 has items such as "sensor head", "cable", "magnetic field sensor", and "distance".

[0115] "Sensor head" refers to identification information for identifying sensor heads 1-2, such as the identification number or symbol of sensor heads 1-2. "Cable" refers to identification information for identifying cable 9, which is the conductor to be measured, such as the identification number or symbol of cable 9 on which sensor heads 1-2 are installed. "Magnetic field sensor" refers to identification information for identifying magnetic field sensor 4, such as the identification number or symbol of magnetic field sensor 4. "Distance" is distance data D2 between magnetic field sensor 4 and the center of cable 9, expressed in millimeters (mm), centimeters (cm), meters (m), etc.

[0116] In other words, Figure 12 shows an example in which data such as distance data D2 being {magnetic field sensor: "MS001", distance: "D001-MS"}, {magnetic field sensor: "MS002", distance: "D002-MS"}, {magnetic field sensor: "MS003", distance: "D003-MS"}, etc., is stored in the second detection data storage unit 24a-2 for sensor heads 1-2 identified by "H001" and cable 9 identified by "C001".

[0117] (2-3-1-2. Second position data storage unit 24b-2) The second position data storage unit 24b-2 stores the second position data. For example, the second position data storage unit 24b-2 stores position data L2 indicating the cable center position CC of the cable 9, which has been identified from the distance data D2 by the identification unit 25b of the control unit 25, which will be described later. Here, an example of the data stored by the second position data storage unit 24b-2 will be explained using Figure 13. Figure 13 is a diagram showing an example of the second position data storage unit 24b-2 of the current measuring device 2-2 according to the embodiment. In the example in Figure 13, the second position data storage unit 24b-2 has items such as "sensor head", "cable", and "center position".

[0118] "Sensor head" refers to identification information for identifying sensor heads 1-2, such as the identification number or identification symbol of sensor heads 1-2. "Cable" refers to identification information for identifying cable 9, which is the conductor to be measured, such as the identification number or identification symbol of cable 9 on which sensor heads 1-2 are installed. "Center position" is position data L2 indicating the center position CC of cable 9, which is represented, for example, by the 3D coordinates of the point that passes through the center of the cylindrical cable 9 and is closest to the magnetic field sensor position MS of magnetic field sensor 4, or the distance r from the magnetic field sensor position MS.

[0119] In other words, Figure 13 shows an example in which data such as position data L2 being {center position: "CC001-MS"} is stored in the second position data storage unit 24b-2 for the sensor head 1-2 identified by "H001" and the cable 9 identified by "C001".

[0120] (2-3-2. Control Unit 25) The control unit 25 is responsible for controlling the entire current measuring device 2-2. The control unit 25 has an acquisition unit 25a, a specification unit 25b, and a calculation unit 25c. Here, the control unit 25 can be implemented by, for example, an electronic circuit such as a CPU or MPU, or an integrated circuit such as an ASIC or FPGA.

[0121] (2-3-2-1. Acquisition part 25a) The acquisition unit 25a acquires various types of information. The acquisition unit 25a may also store the acquired information in the storage unit 24-2. The magnetic field data acquisition process and the second detection data acquisition process will be described below.

[0122] (Magnetic field data acquisition process) The acquisition unit 25a performs magnetic field data acquisition processing. For example, the acquisition unit 25a acquires the detection result of the magnetic field sensor 4. At this time, the acquisition unit 25a acquires the magnetic field strength (A / m) converted by the probe 5 according to the sensor voltage value V1 detected by the magnetic field sensor 41 at the magnetic field sensor position MS, etc., as the detection result magnetic field data M.

[0123] A specific example of the magnetic field data acquisition process will be described. Firstly, the acquisition unit 25a acquires magnetic field data M, which is detected by the magnetic field sensor 41 identified by "MS001" and converted by the probe 5, for the sensor head 1-2 identified by "H001" and the cable 9 identified by "C001", and for the magnetic field sensor 41 identified by "MS001", and converted by the probe 5, as {time: "T001", magnetic field: "M001"}, {time: "T002", magnetic field: "M002"}, {time: "T003", magnetic field: "M003"}, ... Secondly, the acquisition unit 25a stores the acquired magnetic field data M in the current data storage unit 24c.

[0124] The acquisition unit 25a can also acquire the sensor voltage value V1 detected by the magnetic field sensor 41 as magnetic field data M and store it in the current data storage unit 24c. Alternatively, the acquisition unit 25a can acquire the sensor voltage value V1 detected by the magnetic field sensor 41 as magnetic field data M, convert the acquired sensor voltage value V1 into magnetic field strength (A / m), and store the converted magnetic field strength (A / m) in the current data storage unit 24c.

[0125] (Second detection data acquisition process) The acquisition unit 25a executes a second detection data acquisition process. For example, the acquisition unit 25a acquires the detection result of a predetermined sensor as the second detection data. In this case, the acquisition unit 25a assumes that the predetermined sensor includes a plurality of magnetic field sensors 4 (41, 42, ...), and acquires the detection result of each of the plurality of magnetic field sensors 4 (41, 42, ...) as the detection result of the predetermined sensor. The acquisition unit 25a also acquires a plurality of distance data D2 indicating the distance (m) from each of the plurality of magnetic field sensors 4 (41, 42, ...) to the cable 9, which has been converted by the probe 5 according to the sensor values ​​of the plurality of magnetic field sensors 4 (41, 42, ...).

[0126] A specific example of the second detection data acquisition process will now be described. Firstly, the acquisition unit 25a acquires "D001-MS" as distance data D2(1) for the sensor head 1-2 identified by "H001" and cable 9 identified by "C001", the magnetic field sensor 41 identified by "MS001" is detected and converted by the probe 5, "D002-MS" as distance data D2(2) for the magnetic field sensor 42 identified by "DS002" is detected and converted by the probe 5, and "D003-MS" as distance data D2(3) for the magnetic field sensor 43 identified by "MS003" is detected and converted by the probe 5. Secondly, the acquisition unit 25a stores the acquired distance data D2(1), D2(2), and D2(3) in the second detection data storage unit 24a-2.

[0127] The acquisition unit 25a can also acquire sensor voltage values ​​V1, V2, ... detected by multiple magnetic field sensors 4 (41, 42, ...) as distance data D2 and store them in the second detection data storage unit 24a-2. Alternatively, the acquisition unit 25a can acquire sensor voltage values ​​V1, V2, ... detected by multiple magnetic field sensors 4 (41, 42, ...) as distance data D2, convert the acquired sensor voltage values ​​V1, V2, ... into distance (m), and store the converted distance (m) in the second detection data storage unit 24a-2.

[0128] (2-3-2-2. Specific part 25b) The identification unit 25b identifies various types of information. The identification unit 25b may also store the identified information in the storage unit 24-2. The position data output process will be described below.

[0129] (Location data output processing) The identification unit 25b performs position data output processing. For example, the identification unit 25b uses the detection results (second detection data) of each of the acquired magnetic field sensors 4 (41, 42, ...) to identify the cable center position CC of the conductor cable 9. At this time, the identification unit 25b uses the acquired distance data D2 to identify the cable center position CC of the cable 9.

[0130] A specific example of the position data output processing will be described. Firstly, the identification unit 25b refers to the distance data D2, {magnetic field sensor: "MS001", distance: "D001-MS"} and {magnetic field sensor: "MS002", distance: "D002-MS"}, as second detection data stored in the second detection data storage unit 24a-2 for the sensor head 1-2 identified by "H001" and the cable 9 identified by "C001". Secondly, the identification unit 25b refers to the magnetic field sensor position MS-1 of the magnetic field sensor 41, "L001-MS", and the magnetic field sensor position MS-2 of the magnetic field sensor 42, "L002-MS", as setting values ​​stored in the storage unit 24-2 for the sensor head 1-2 identified by "H001" and the cable 9 identified by "C001". Thirdly, the identification unit 25b identifies the cable center position CC of the cable 9 by drawing a perfect circle on the XY plane with "L001-MS" as the center and "D001-MS" as the radius, and a perfect circle on the XY plane with "L002-MS" as the center and "D002-MS" as the radius, for the sensor head 1-2 identified by "H001" and the cable 9 identified by "C001", and outputs position data L2, which is {center position: "CC001-MS"}. Fourthly, the identification unit 25b stores the output position data L2 in the second position data storage unit 24b-2.

[0131] (2-3-2-3. Calculation part 25c) The calculation unit 25c acquires various information. The calculation unit 25c may also store the calculated information in the storage unit 24-2. The current data calculation process will be described below.

[0132] (Current data calculation process) The calculation unit 25c performs current data calculation processing. For example, the calculation unit 25c calculates the current value (A) of the current I flowing through the cable 9 as current data A, based on the cable center position CC of the identified conductor cable 9 and the detection result of the acquired magnetic field sensor 4. At this time, the calculation unit 25c calculates the current value (A) of the current I flowing through the cable 9 based on the detection result of at least one of the multiple magnetic field sensors 4 (41, 42, ...) and the cable center position CC of the identified cable 9.

[0133] A specific example of the current data calculation process will be explained. Firstly, the calculation unit 25c refers to the position data L2, which is {center position: "CC001-MS"}, as the second position data stored in the second position data storage unit 24b-2 for the sensor head 1-2 identified by "H001" and the cable 9 identified by "C001", and determines the distance r (m) from the magnetic field sensor position MS-1 of the magnetic field sensor 41 to the cable center position CC. Secondly, the calculation unit 25c obtains the magnetic field data M, which is {time: "T001", magnetic field: "M001"}, {time: "T002", magnetic field: "M002"}, {time: "T003", magnetic field: "M003"}, ..., stored in the current data storage unit 24c for the sensor head 1-2 identified by "H001" and the cable 9 identified by "C001". Thirdly, the calculation unit 25c calculates current data A, such as {time: "T001", current: "A001"}, {time: "T002", current: "A002"}, {time: "T003", current: "A003"}, ... by substituting the distance r (m) and the magnetic field strength (A / m) indicated by the magnetic field data M into the formula H = I / (2πr) derived from Ampère's law. Fourthly, the calculation unit 25c stores the calculated current data A in the current data storage unit 24c.

[0134] Furthermore, the calculation unit 25c may use only the magnetic field data M acquired from the specified magnetic field sensor 4 for the current data calculation process, or it may use the magnetic field data M acquired from multiple magnetic field sensors 4 (41, 42, ...) that output distance data D2 for the current data calculation process. That is, any of the magnetic field data M such as multiple sensor voltage values ​​V1, V2, ... output from multiple magnetic field sensors 4 (41, 42, ...) may be used to calculate the distance data D2, or any of the data may be used to calculate the current data A. In addition, the calculation unit 25c can also use the distance data D1 output from the distance measuring sensor 6 according to Embodiment 1.

[0135] (2-4. Example configuration and processing of Probe 5) Using Figure 11, an example of the configuration and processing of probe 5 will be explained. Probe 5 includes a detection circuit 51 and converts the detection results of the magnetic field sensor 4. For example, probe 5 converts the sensor voltage values ​​V1, V2, ... detected by multiple magnetic field sensors 4 (41, 42, ...) into magnetic field strength (A / m).

[0136] Probe 5 converts the sensor voltage values ​​V1, V2, ... detected by multiple magnetic field sensors 4 (41, 42, ...) into distance data D2. For example, Probe 5 converts the magnetic field strength (A / m) of the magnetic field H generated by a current I with a constant current amount (A) flowing through cable 9 into distance data D2 by substituting it into the formula H = I / (2πr) derived from Ampere's law.

[0137] [3. Flow of each process in the current measurement system 100-2] The processing flow of the current measurement system 100-2 according to Embodiment 2 will be explained using Figure 14. Figure 14 is a flowchart showing an example of the processing flow of the current measurement system 100-2 according to Embodiment 2. Note that the processes in steps S201 to S210 below can be executed in a different order. Also, some of the processes in steps S201 to S210 below may be omitted.

[0138] (3-1. Second detection data measurement process) Firstly, the current measurement system 100-2 performs a second detection data measurement process (step S201). For example, the sensor head 1-2 outputs a sensor voltage value V1 as second detection data, corresponding to the magnetic field H at the magnetic field sensor position MS-1 of the magnetic field sensor 41. The sensor head 1-2 also outputs a sensor voltage value V2 as second detection data, corresponding to the magnetic field H at the magnetic field sensor position MS-2 of the magnetic field sensor 42.

[0139] (3-2. Second detection data acquisition process) Secondly, the current measurement system 100-2 performs a second detection data acquisition process (step S202). For example, the current measurement device 2-2 acquires distance data D2(1) as second detection data, which is obtained by the probe 5 converting the sensor voltage value V1 detected by the magnetic field sensor 41 into the distance (m) from the magnetic field sensor 41 to the center of the cable 9. The current measurement device 2-2 also acquires distance data D2(2) as second detection data, which is obtained by the probe 5 converting the sensor voltage value V2 detected by the magnetic field sensor 42 into the distance (m) from the magnetic field sensor 42 to the center of the cable 9.

[0140] (3-3. Second detection data storage process) Thirdly, the current measurement system 100-2 performs a second detection data storage process (step S203). For example, the current measurement device 2-2 stores the distance data D1(1) and distance data D1(2) acquired from the sensor head 1-2 as second detection data in the second detection data storage unit 24a-2.

[0141] (3-4. Second detection data reference processing) Fourth, the current measurement system 100-2 performs a second detection data reference process (step S204). For example, the current measurement device 2-2 refers to the distance data D1(1) and distance data D1(2) stored in the second detection data storage unit 24a-2 as the second detection data. The current measurement device 2-2 also refers to the magnetic field sensor position MS-1 of the magnetic field sensor 41 and the magnetic field sensor position MS-2 of the magnetic field sensor 42, which are set values ​​stored in the storage unit 24-2.

[0142] (3-5. Second position data calculation process) Fifth, the current measurement system 100-2 performs a second position data calculation process (step S205). For example, the current measurement device 2-2 uses distance data D2(1), distance data D2(2), magnetic field sensor position MS-1, and magnetic field sensor position MS-2 as second position data to calculate position data L2 indicating the cable center position CC of cable 9.

[0143] (3-6. Second position data storage process) Sixth, the current measurement system 100-2 performs a second position data storage process (step S206). For example, the current measurement device 2-2 stores position data L2, which includes the calculated three-dimensional coordinates of the cable center position CC and the distance r from the magnetic field sensor position MS, as second position data in the second position data storage unit 24b-2.

[0144] (3-7. Second position data reference processing) Seventh, the current measuring system 100-2 performs a second position data reference process (step S207). For example, the current measuring device 2-2 refers to the position data L2 stored in the second position data storage unit 24b-2 as the second position data.

[0145] (3-8. Magnetic field data reference processing) Eighth, the current measurement system 100-2 performs magnetic field data reference processing (step S208). For example, the current measurement device 2-2 references the magnetic field data M stored in the current data storage unit 24c, which corresponds to the detection result of the magnetic field sensor 41 closest to the cable 9, based on the magnetic field strength (A / m) detected by the multiple magnetic field sensors 4 (41, 42, ...).

[0146] (3-9. Current Data Calculation Process) Ninth, the current measurement system 100-2 performs current data calculation processing (step S209). For example, the current measurement device 2-2 uses position data L2 and magnetic field data M to calculate current data A, which indicates the current value (A) of the current I flowing through the cable 9 at regular intervals.

[0147] (3-10. Current Data Storage Process) Tenth, the current measurement system 100-2 performs current data storage processing (step S210) and terminates the process. For example, the current measurement device 2-2 stores the calculated current data A in the current data storage unit 24c. At this time, the current measurement device 2-2 can also display the calculated current data A as a waveform of current I on the output unit 22, which is a display.

[0148] [4. Effects of Embodiment 2] The effects of Embodiment 2 will now be described. Below, Effect 1 and Effect 2, which correspond to the processing according to Embodiment 2, will be explained.

[0149] (4-1. Effect 1) Firstly, in the process according to Embodiment 2 described above, the current measurement system 100-2 includes a magnetic field shield 3 configured to take in the magnetic field H generated by the current I flowing through the cable 9, a magnetic field sensor 4 installed inside the magnetic field shield 3, and a current measurement device 2-2. The current measurement device 2-2 acquires detection results from a plurality of magnetic field sensors 4 (41, 42, ...) installed at different positions, identifies the cable center position CC of the cable 9 based on the acquired detection results from the plurality of magnetic field sensors 4 (41, 42, ...), and calculates the current value (A) of the current I flowing through the cable 9 based on the identified cable center position CC and the acquired detection results from the magnetic field sensors 4. Therefore, in this process, by using a plurality of magnetic field sensors 4 (41, 42, ...) as predetermined sensors for detecting the cable 9, the measurement accuracy of the current I flowing through the cable 9 can be improved.

[0150] (4-2. Effect 2) Secondly, in the process according to Embodiment 2 described above, the current measuring device 2-2 calculates the current value (A) of the current I flowing through the cable 9 based on the detection result of at least one of the multiple magnetic field sensors 4 (41, 42, ...) and the identified cable center position CC. Therefore, in this process, the measurement accuracy of the current I flowing through the cable 9 can be improved by using any detection result from the multiple magnetic field sensors 4 (41, 42, ...).

[0151] [Embodiment 3] The configuration and processing of the current measurement system 100-3 according to Embodiment 3, the configuration and processing of each device in the current measurement system 100-3, the flow of each process in the current measurement system 100-3, and the effects of the embodiment will be described below. Note that configurations and processes common to Embodiment 1 or Embodiment 2 will not be described.

[0152] [1. Configuration and operation of current measurement system 100-3] Using Figure 15, the configuration and processing of the current measurement system 100-3 according to Embodiment 3 will be described. Below, an example of the overall configuration of the current measurement system 100-3, an example of the configuration of the sensor head 1-3, an example of the processing of the current measurement system 100-3, and the effects of the current measurement system 100-3 will be described. Note that the example configuration of the magnetic field shield 3 and the example configuration of the cable 9 are the same as in Embodiment 1, so their explanation will be omitted.

[0153] (1-1. Example of the overall configuration of the current measurement system 100-3) An example of the overall configuration of the current measurement system 100-3 will be explained using Figure 15. The current measurement system 100-3 consists of a sensor head 1-3, a current measuring device 2-3, a probe 5, and a cable fixing device 7. Figure 15 is a diagram showing an example of the configuration and processing of the current measurement system 100-3 according to Embodiment 3. Here, the sensor head 1-3, the current measuring device 2-3, and the probe 5 are connected to each other via a predetermined communication network, either by wire or wireless communication. Various communication networks such as the internet or dedicated lines can be used as the predetermined communication network.

[0154] (1-1-1. Sensor head 1-3) Sensor heads 1-3 are sensor devices that are attached to the cable 9, which is the conductor to be measured, by cable fasteners 7, and measure the magnetic field H generated by the current I flowing through the cable 9. Sensor heads 1-3 are covered by a magnetic field shield 3 with a partial opening on the bottom surface, and a magnetic field sensor 4 and a state sensor 8 are installed inside. Note that the current measurement system 100-3 shown in Figure 15 may include multiple sensor heads 1-3. Note that the direction of the current I, the direction of the magnetic field, and the XYZ coordinate system are the same as in Embodiment 1, so their explanation will be omitted.

[0155] The magnetic field shield 3 takes in (a portion of) the magnetic field H generated by the current I flowing through the cable 9 into its internal space 30 through its opening 37. The magnetic field sensor 4 detects the magnetic field H taken in into the internal space 30 of the magnetic field shield 3 and outputs it as a sensor voltage value V1. At this time, the magnetic field sensor 4 outputs the sensor voltage value V1 to the detection circuit 51 built into the probe 5 via the terminal 38 and wiring W1 of the magnetic field shield 3. The state sensor 8 outputs the sensor value, which is the detection result, to the current measuring device 2-3 via a predetermined communication network (not shown).

[0156] (1-1-2. Current measuring device 2-3) The current measuring device 2-3 is a device that identifies the cable center position CC of the cable 9, which is the conductor to be measured, and measures the current I flowing through the cable 9. Note that the current measuring system 100-3 shown in Figure 15 may include multiple current measuring devices 2-3. Furthermore, while the example in Figure 15 shows the current measuring device 2-3 being implemented using an oscilloscope, it may also be implemented using a desktop PC, notebook PC, smartphone, server device, cloud system, etc.

[0157] The current measuring device 2-3 has an input unit 21 and an output unit 22. In the example shown in Figure 15, the input unit 21 is an input terminal connected to the probe 5. The output unit 22 is a display that shows the waveform of the measured current I.

[0158] (1-1-3. Probe 5) Probe 5 is a device that is communicatively connected between the current measuring device 2-3 and the sensor head 1-3 by wiring W1, and incorporates a detection circuit 51 that converts the sensor voltage value V1 detected by the sensor head 1-3. Note that the current measuring system 100-3 shown in Figure 15 may include multiple probes 5. Furthermore, the probe 5 may be integrated with the current measuring device 2-3 or the sensor head 1-3.

[0159] (1-1-4. Cable fastener 7) The cable fixing device 7 is a device for fixing the cable 9 to the sensor head 1-3. Note that the current measurement system 100-3 shown in Figure 15 may include multiple cable fixing devices 7.

[0160] (1-2. Example configuration of sensor head 1-3) An example of the configuration of the sensor head 1-3 will be described using Figure 16. Figure 16 is a diagram showing an example of the configuration of the sensor head 1-3 according to Embodiment 3. The sensor head 1-3 has a magnetic field shield 3, a magnetic field sensor 4, and a state sensor 8. In the example of Figure 16, the sensor head 1-3 is installed on the cable 9 via a cable fixing device 7 so as to pass through the opening 37 at the bottom of the magnetic field sensor 4. At this time, the sensor head 1-3 may use, for example, a hook-shaped member, a ring-shaped member, etc. to attach the magnetic field shield 3 to the cable fixing device 7, or a spring member, etc. to fix the attachment. Furthermore, the sensor head 1-3 may have the magnetic field sensor 4 built into the magnetic field shield 3 so that the magnetic field sensor 4 is positioned in the vertical direction of the cable 9, or it may have the magnetic field sensor 4 built into the magnetic field shield 3 so that the magnetic field sensor 4 is positioned offset from the vertical direction of the cable 9, and the installation position of the magnetic field sensor 4 is not particularly limited. Furthermore, the sensor heads 1-3 only need to have a state sensor 8 in a position capable of detecting a state such as the deformation amount W of the cable fixing device 7, and there are no particular limitations on the installation position of the state sensor 8. In the following, the installation position of the magnetic field sensor 4 in the XZ plane direction of the sensor heads 1-3 will be described as the magnetic field sensor position MS, and the center of the cable 9 closest to the magnetic field sensor position MS in the XY plane direction will be described as the cable center position CC.

[0161] (1-3. Example of cable fastener 7 configuration) Using Figures 17 to 20, we will explain the configuration examples of the cable fastener 7. Below, we will describe cable fastener 7-1 as configuration example 1 of cable fastener 7, and cable fastener 7-2 as configuration example 2 of cable fastener 7.

[0162] (1-3-1. Configuration Example 1) Using Figures 17 and 18, we will describe cable fastener 7-1 as example configuration 1 of cable fastener 7. Figure 17 is a diagram showing example configuration 1-1 of cable fastener 7 according to embodiment 3. Figure 18 is a diagram showing example configuration 1-2 of cable fastener 7 according to embodiment 3. Below, we will describe cable fastener 7-1, in which the clamping portion 71 that holds the cable 9 is not deformable, as example configuration 1 of cable fastener 7.

[0163] Figure 17(1) shows a schematic diagram of the cable 9 in the XY plane. As shown in Figure 17(1), the current measurement system 100-3 accurately measures the current I flowing through the cable 9 by identifying the precise cable center position CC of the cable 9 and accurately calculating the distance r(m) from the magnetic field sensor position MS of the magnetic field sensor 4 to the cable center position CC. At this time, the current measurement system 100-3 measures the deformation amount W of the deformed part 72-1 of the cable fixing device 7-1, calculates the cable radius d of the cable 9 according to the measured deformation amount W, and identifies the cable center position CC using the calculated cable radius d and the fixing device position CF, which is the installation position of the cable fixing device 7, which is a set value.

[0164] Figures 17(2) to (4) show schematic diagrams of the cable fastener 7-1 and cable 9 in the XY plane. As shown in Figures 17(2) to (4), the cable fastener 7-1 has a clamping portion 71, a deformable portion 72-1, a base portion 73, an extending portion 74, and a lower contact portion 75. In the cable fastener 7-1, the clamping portion 71 and the extending portion 74, which are scissor-shaped with the base portion 73 as a fulcrum, do not deform when the cable 9 is pushed in and fixed. On the other hand, in the cable fastener 7-1, the lower contact portion 75 presses the cable 9 into contact with the clamping portion 71 from below, locking the cable 9 in place by pressing it in from below so that there is no gap. That is, in the cable fastener 7-1, the lower contact portion 75 corresponds to the deformable portion 72-1 which moves in the Y-axis direction according to the cable radius d of the cable 9. The examples in Figures 17(2) to (4) show that the smaller the cable radius d of cable 9, the more the lower contact portion 75 moves upward, and the larger the cable radius d of cable 9, the more the lower contact portion 75 moves downward.

[0165] Figure 18(1) shows a schematic diagram of the cable fastener 7-1 and cable 9 in the XY plane. Figure 18(2) shows a schematic diagram of the cable fastener 7-1 and cable 9 in the YZ plane, corresponding to Figure 18(1). As shown in Figures 18(1) and (2), the cable fastener 7-1 may also have a plate 76 and a spring 77 as a deformable part 72-1, in addition to the lower contact part 75. In the example of Figure 18(2), the spring 77 connected to the plate 76 is pressed into the lower contact part 75 according to the cable radius d of the cable 9, and it can be seen that the shorter the width WA from the plate 76 to the lowest end of the spring 77, the larger the cable radius d. That is, the current measurement system 100-3 can calculate the cable radius d of the cable 9 by detecting the width WA of the cable fastener 7-1 with the state sensor 8, and the cable center position CC can be identified.

[0166] (1-3-2. Configuration Example 2) Using Figures 19 and 20, we will describe cable fastener 7-2 as example 2 of the configuration of cable fastener 7. Figure 19 is a diagram showing example 2-1 of the configuration of cable fastener 7 according to embodiment 3. Figure 20 is a diagram showing example 2-2 of the configuration of cable fastener 7 according to embodiment 3. Below, we will describe cable fastener 7-2, in which the clamping portion 71 that holds the cable 9 is deformable, as example 2 of the configuration of cable fastener 7.

[0167] Figure 19(1) shows a schematic diagram of the cable 9 in the XY plane. As shown in Figure 19(1), the current measurement system 100-3 accurately measures the current I flowing through the cable 9 by identifying the precise cable center position CC of the cable 9 and accurately calculating the distance r(m) from the magnetic field sensor position MS of the magnetic field sensor 4 to the cable center position CC. At this time, the current measurement system 100-3 measures the amount of deformation W of the deformed part 72-2 of the cable fixing device 7-2, calculates the cable radius d of the cable 9 according to the measured amount of deformation W, and identifies the cable center position CC using the calculated cable radius d and the fixing device position CF, which is the set value of the installation position of the cable fixing device 7.

[0168] Figures 19(2) to (4) show schematic diagrams of the cable fastener 7-2 and cable 9 in the XY plane. As shown in Figures 19(2) to (4), the cable fastener 7-2 has a clamping portion 71, a deformable portion 72-2, a base portion 73, an extending portion 74, a lower contact portion 75, and an upper contact portion 78. In the cable fastener 7-2, the clamping portion 71 and the extending portion 74, which are scissor-shaped with the base portion 73 as a fulcrum, deform when the cable 9 is pushed in and fixed. On the other hand, in the cable fastener 7-2, the lower contact portion 75 presses the cable 9 in contact with the upper contact portion 78 fixed to the clamping portion 71 from below, and locks the cable 9 in place by pressing it in from below so that there is no gap. That is, in the cable fastener 7-2, the extending portion 74 corresponds to the deformable portion 72-2, which moves so that the paired structure opens in the X-axis direction according to the cable radius d of the cable 9. The examples in Figures 19(2) to (4) show that the smaller the cable radius d of cable 9, the smaller the deformation width WB-1 at which the extended portion 74 opens, and the larger the cable radius d of cable 9, the larger the deformation width WB-1 at which the extended portion 74 opens.

[0169] Figure 20(1) shows a schematic diagram of the cable fastener 7-2 and cable 9 in the XY plane. Figure 20(2) shows a schematic diagram of the cable fastener 7-2 and cable 9 in the YZ plane, corresponding to Figure 20(1). As shown in Figures 20(1) and (2), the cable fastener 7-2 may also have a plate 76 and a spring 77 as a deformable part 72-2, in addition to the lower contact part 75 and the upper contact part 78. In the example of Figure 20(2), depending on the cable radius d of the cable 9, the spring 77 connected to the plate 76 is pressed into the lower contact part 75, and it can be seen that the shorter the deformation width WB-2 from the top of the plate 76 to the lowest end of the spring 77, the larger the cable radius d. That is, the current measurement system 100-3 can calculate the cable radius d of the cable 9 by detecting the deformation width WB-1 or deformation width WB-2 of the cable fastener 7-1 with the state sensor 8, and identify the cable center position CC.

[0170] (1-3. Example of processing by current measurement system 100) This section describes an example of the current measurement system 100-3. The following describes the width data measurement process, width data acquisition process, cable center position identification process, and current data calculation process. Note that the above processes can be executed in a different order. Furthermore, some of the above processes may be omitted.

[0171] (1-3-1. Width data measurement processing) Firstly, the sensor heads 1-3 measure width data D3 indicating the state of the cable fastener 7. At the same time, the sensor heads 1-3 measure width data D3 indicating the amount of deformation W of the deformed portion 72 of the cable fastener 7, which is detected by the state sensor 8.

[0172] (1-3-2. Width data acquisition process) Secondly, the current measuring device 2-3 acquires width data D3 from the sensor head 1-3. For example, the current measuring device 2-3 acquires width data D3 from the sensor head 1-3 according to the detection result of the state sensor 8.

[0173] (1-3-3. Cable center position identification process) Thirdly, the current measuring device 2-3 identifies the cable center position CC of the cable 9. For example, the current measuring device 2-3 identifies the cable center position CC of the cable 9 using width data D3 corresponding to the detection result of the state sensor 8. At this time, the current measuring device 2-3 further identifies the cable center position CC using the fixed position CF of the cable fixing device 7, which is a set value, and the magnetic field sensor position MS of the magnetic field sensor 4.

[0174] (1-3-4. Current Data Calculation Process) Fourth, the current measuring device 2-3 calculates current data A of the current I flowing through the cable 9. For example, the current measuring device 2-3 uses the cable center position CC of the identified cable 9 and the magnetic field data M obtained from the magnetic field sensor 4 to calculate current data A, which indicates the current value (A) of the current I flowing through the cable 9 at regular intervals.

[0175] (1-4. Effects of the current measurement system 100-3) After describing the outline of the current measurement system 100-3 according to Embodiment 3, the effects of the current measurement system 100-3 will be explained.

[0176] (1-4-1. Overview of Current Measurement System 100-3) An overview of the current measurement system 100-3 according to Embodiment 3 will be described. The current measurement system 100-3 performs the following processes. First, the sensor head 1-3 measures width data D3 indicating the state of the cable fixing device 7 via the state sensor 8. Second, the current measurement device 2-3 acquires the width data D3 from the sensor head 1-3. Third, the current measurement device 2-3 uses the width data D3 to identify the cable center position CC of the cable 9. Fourth, the current measurement device 2-3 uses the cable center position CC and magnetic field data M to calculate current data A indicating the current value (A) of the current I flowing through the cable 9.

[0177] (1-4-2. Effects of the current measurement system 100-3) The effects of the current measurement system 100-3 according to Embodiment 3 will now be described. The current measurement system 100-3 installs a sensor head 1-3 on the cable 9 using a cable fixing device 7, and collects width data D3 corresponding to the deformation amount W of the cable fixing device 7 using a state sensor 8 that detects the state of the cable fixing device 7, thereby accurately identifying the cable center position CC for calculating the current value (A) of the current I flowing through the cable 9. Therefore, the current measurement system 100-3 can improve the measurement accuracy of the current I flowing through the cable 9.

[0178] [2. Configuration and operation of each device in the current measurement system 100-3] Using Figures 21 to 23, the configuration and processing of each device in the current measurement system 100-3 shown in Figure 15 will be explained. Below, an example of the overall configuration of the current measurement system 100-3 according to Embodiment 3, an example of the configuration and processing of the sensor head 1-3, an example of the configuration and processing of the current measurement device 2-3, an example of the configuration and processing of the probe 5, and an example of the configuration and processing of the cable fixing device 7 will be explained.

[0179] (2-1. Example of the overall configuration of the current measurement system 100-3) Using Figure 21, an example of the overall configuration of the current measurement system 100-3 shown in Figure 15 will be explained. Figure 21 is a block diagram showing an example of the configuration of each device in the current measurement system 100-3 according to Embodiment 3. As shown in Figure 21, the current measurement system 100-3 consists of a sensor head 1-3, a current measuring device 2-3, a probe 5, and a cable fixing device 7. The sensor head 1-3 and the current measuring device 2-3 are connected via the probe 5 so as to be able to communicate using a dedicated line or the like. The current measuring device 2-3 and the state sensor 8 are connected so as to be able to communicate using a communication network N, which is implemented via the internet or a dedicated line or the like.

[0180] (2-2. Example configuration and processing of sensor head 1-3) Using Figure 21, an example of the configuration and processing of sensor head 1-3 will be explained. As shown in Figure 21, sensor head 1-3 is composed of a magnetic field shield 3, a magnetic field sensor 4, and a state sensor 8.

[0181] (2-2-1. Magnetic field shielding 3) The magnetic field shield 3 is configured to take in the magnetic field H generated by the current I flowing through the conductor cable 9. The magnetic field shield 3 is also configured to shield the magnetic field H. The magnetic field shield 3 may be made of various known materials, including metallic materials.

[0182] (2-2-2. Magnetic field sensor 4) The magnetic field sensor 4 is installed inside the magnetic field shield 3. The magnetic field sensor 4 detects the magnetic field H at the installation location, magnetic field sensor position MS. For example, the magnetic field sensor 4 is an IC sensor that includes a Hall element, and is also called an analog Hall IC. Alternatively, the magnetic field sensor 4 may be a coil sensor that includes a coil. In this case, the magnetic field sensor 4 may use a Rogowski coil, which allows for miniaturization and thus facilitates the placement of the magnetic field sensor 4 inside the magnetic field shield 3.

[0183] (2-2-3. State Sensor 8) The state sensor 8 is an example of a predetermined sensor for detecting the cable 9. The state sensor 8 detects the state of the cable fastener 7. For example, the state sensor 8 detects the state of the cable fastener 7 based on output values ​​such as the stress of the spring 77, a piezoelectric element, or a strain gauge. The state sensor 8 also detects the amount of deformation W of the deformed portion 72 of the cable fastener 7. At this time, the state sensor 8 detects a width WA indicating the displacement of the spring 77 included in the deformed portion 72-1. The state sensor 8 also detects a width WB indicating the distance between a pair of extended portions 74 included in the deformed portion 72-2. In the example shown in Figure 21, the state sensor 8 is installed inside the sensor head 1-3, but it may be installed outside the sensor head 1-3, or multiple state sensors 8 may be installed.

[0184] (2-3. Example configuration and processing of current measuring device 2-3) Using Figure 21, an example of the configuration and processing of the current measuring device 2-3 will be explained. As shown in Figure 21, the current measuring device 2-3 is composed of an input unit 21, an output unit 22, a communication unit 23, a storage unit 24-2, and a control unit 25. Note that the input unit 21, output unit 22, and communication unit 23 are the same as in Embodiment 1, so their explanation will be omitted.

[0185] (2-3-1. Storage section 24-3) The storage unit 24-3 stores various information that the control unit 25 refers to when it operates, and various information acquired when the control unit 25 operates. The storage unit 24-3 includes a third detection data storage unit 24a-3, a third position data storage unit 24b-3, and a current data storage unit 24c. Here, the storage unit 24-3 can be implemented as, for example, a semiconductor memory element such as RAM or flash memory, or a storage device such as a hard disk or optical disc. In the example in Figure 21, the storage unit 24-3 is installed inside the current measuring device 2-3, but it may be installed outside the current measuring device 2-3, or multiple storage units may be installed. Furthermore, the current data storage unit 24c is the same as in Embodiment 1, so its explanation is omitted.

[0186] (2-3-1-1. Third detection data storage unit 24a-3) The third detection data storage unit 24a-3 stores the third detection data. For example, the third detection data storage unit 24a-3 stores the width data D3, which corresponds to the sensor value detected by the state sensor 8 and is acquired by the acquisition unit 25a of the control unit 25 (described later), as the third detection data. Here, an example of the data stored by the third detection data storage unit 24a-3 will be explained using Figure 22. Figure 22 is a diagram showing an example of the third detection data storage unit 24a-3 of the current measuring device 2-3 according to Embodiment 3. In the example in Figure 22, the third detection data storage unit 24a-3 has items such as "sensor head", "cable", "state sensor", and "width".

[0187] "Sensor head" indicates identification information for identifying sensor heads 1-3, such as the identification number or identification symbol of sensor heads 1-3. "Cable" indicates identification information for identifying cable 9, which is the conductor to be measured, such as the identification number or identification symbol of cable 9 on which sensor heads 1-3 are installed. "State sensor" indicates identification information for identifying state sensor 8, such as the identification number or identification symbol of state sensor 8. "Width" is width data D3, which is one of the deformation amounts W of the state of the cable fastener 7 detected by state sensor 8, and is expressed in millimeters (mm), centimeters (cm), meters (m), etc.

[0188] In other words, Figure 22 shows an example in which data such as width data D3 being {state sensor: "WS001", width: "W001"} is stored in the third detection data storage unit 24a-3 for sensor heads 1-3 identified by "H001" and cable 9 identified by "C001".

[0189] (2-3-1-2. Third position data storage unit 24b-3) The third position data storage unit 24b-3 stores the third position data. For example, the third position data storage unit 24b-3 stores position data L3 indicating the cable center position CC of the cable 9, which has been identified from the width data D3 by the identification unit 25b of the control unit 25, which will be described later. Here, an example of the data stored by the third position data storage unit 24b-3 will be explained using Figure 23. Figure 23 is a diagram showing an example of the third position data storage unit 24b-3 of the current measuring device 2-3 according to Embodiment 3. In the example in Figure 23, the third position data storage unit 24b-3 has items such as "sensor head", "cable", and "center position".

[0190] "Sensor head" indicates identification information for identifying sensor heads 1-3, such as the identification number or identification symbol of sensor heads 1-3. "Cable" indicates identification information for identifying cable 9, which is the conductor to be measured, such as the identification number or identification symbol of cable 9 on which sensor heads 1-3 are installed. "Center position" is position data L3 indicating the center position CC of cable 9, which is represented by the 3D coordinates of the point that passes through the center of the cylindrical cable 9 and is closest to the magnetic field sensor position MS of magnetic field sensor 4, or the distance r from the magnetic field sensor position MS.

[0191] In other words, Figure 23 shows an example in which data such as position data L3 being {center position: "CC001-W"} is stored in the third position data storage unit 24b-3 for sensor heads 1-3 identified by "H001" and cable 9 identified by "C001".

[0192] (2-3-2. Control Unit 25) The control unit 25 is responsible for controlling the entire current measuring device 2-3. The control unit 25 has an acquisition unit 25a, a specification unit 25b, and a calculation unit 25c. Here, the control unit 25 can be implemented by, for example, an electronic circuit such as a CPU or MPU, or an integrated circuit such as an ASIC or FPGA.

[0193] (2-3-2-1. Acquisition part 25a) The acquisition unit 25a acquires various types of information. The acquisition unit 25a may also store the acquired information in the storage unit 24-3. The magnetic field data acquisition process and the third detection data acquisition process will be described below.

[0194] (Magnetic field data acquisition process) The acquisition unit 25a performs magnetic field data acquisition processing. For example, the acquisition unit 25a acquires the detection result of the magnetic field sensor 4. At this time, the acquisition unit 25a acquires the magnetic field strength (A / m) converted by the probe 5 according to the sensor voltage value V1 detected by the magnetic field sensor 4 at the magnetic field sensor position MS, etc., as the detection result magnetic field data M.

[0195] A specific example of the magnetic field data acquisition process will be described. Firstly, the acquisition unit 25a acquires magnetic field data M, which is detected by the magnetic field sensor 4 identified by "MS001" and converted by the probe 5, for the sensor heads 1-3 identified by "H001" and the cable 9 identified by "C001", and for the magnetic field sensor 4 identified by "MS001", and converted by the probe 5, as {time: "T001", magnetic field: "M001"}, {time: "T002", magnetic field: "M002"}, {time: "T003", magnetic field: "M003"}, ... Secondly, the acquisition unit 25a stores the acquired magnetic field data M in the current data storage unit 24c.

[0196] Furthermore, the acquisition unit 25a can acquire the sensor voltage value V1 detected by the magnetic field sensor 4 as magnetic field data M and store it in the current data storage unit 24c. Alternatively, the acquisition unit 25a can acquire the sensor voltage value V1 detected by the magnetic field sensor 4 as magnetic field data M, convert the acquired sensor voltage value V1 into magnetic field strength (A / m), and store the converted magnetic field strength (A / m) in the current data storage unit 24c.

[0197] (Third detection data acquisition process) The acquisition unit 25a executes the third detection data acquisition process. For example, the acquisition unit 25a acquires the detection result of a predetermined sensor as the third detection data. In this case, the acquisition unit 25a assumes that the predetermined sensor includes the state sensor 8 and acquires the detection result of the state sensor 8 as the detection result of the predetermined sensor. The acquisition unit 25a also acquires width data D3, which is one of the deformation amounts W of the state of the cable fixing device 7, according to the sensor value of the state sensor 8.

[0198] A specific example of the third detection data acquisition process will now be described. First, the acquisition unit 25a acquires "W001" as width data D3 detected by the state sensor 8 identified by "CS001" for the sensor heads 1-3 identified by "H001" and the cable 9 identified by "C001". Second, the acquisition unit 25a stores the acquired width data D3 in the third detection data storage unit 24a-3.

[0199] Furthermore, the acquisition unit 25a can acquire the sensor voltage value VW detected by the state sensor 8 as width data D3 and store it in the third detection data storage unit 24a-3. Alternatively, the acquisition unit 25a can acquire the deformation amount W, which is the distance (m) converted by the probe 5 according to the sensor voltage value VW detected by the state sensor 8, as width data D3 and store it in the third detection data storage unit 24a-3. Alternatively, the acquisition unit 25a can acquire the sensor voltage value VW detected by the state sensor 8 as width data D3, convert the acquired sensor voltage value VW into a deformation amount W, which is the distance (m), and store the converted deformation amount W in the third detection data storage unit 24a-3.

[0200] (2-3-2-2. Specific part 25b) The identification unit 25b identifies various types of information. The identification unit 25b may also store the identified information in the storage unit 24-2. The position data output process will be described below.

[0201] (Location data output processing) The identification unit 25b performs position data output processing. For example, the identification unit 25b uses the acquired detection result (third detection data) of the state sensor 8 to identify the cable center position CC of the conductor cable 9. At this time, the identification unit 25b uses the acquired width data D3 to identify the cable center position CC of the cable 9.

[0202] A specific example of the position data output processing will be described. Firstly, the identification unit 25b refers to the width data D3, {state sensor: "CS001", width: "W001"}, as the third detection data stored in the third detection data storage unit 24a-3 for the sensor head 1-3 identified by "H001" and the cable 9 identified by "C001". Secondly, the identification unit 25b refers to the magnetic field sensor position MS of the magnetic field sensor 4, "L001-MS", as the setting value stored in the storage unit 24-3 for the sensor head 1-3 identified by "H001" and the cable 9 identified by "C001". Thirdly, the identification unit 25b refers to the fixing device position CF of the cable fixing device 7, "L001-CF", as the setting value stored in the storage unit 24-3 for the sensor head 1-3 identified by "H001" and the cable 9 identified by "C001". Fourth, the identification unit 25b outputs position data L3, which is {center position: "CC001-W"}, using the width data D3, the magnetic field sensor position MS of the magnetic field sensor 4, and the fixing position CF of the cable fixing device 7 for the sensor heads 1-3 identified by "H001" and the cable 9 identified by "C001". Fourth, the identification unit 25b stores the output position data L3 in the third position data storage unit 24b-3.

[0203] (2-3-2-3. Calculation part 25c) The calculation unit 25c acquires various information. The calculation unit 25c may also store the calculated information in the storage unit 24-3. The current data calculation process will be described below.

[0204] (Current data calculation process) The calculation unit 25c performs current data calculation processing. For example, the calculation unit 25c calculates the current value (A) of the current I flowing through the cable 9 as current data A, based on the cable center position CC of the cable 9, which is the identified conductor, and the detection result obtained from the magnetic field sensor 4.

[0205] A specific example of the current data calculation process will be explained. Firstly, the calculation unit 25c refers to the position data L3, which is {center position: "CC001-W"}, as the third position data stored in the third position data storage unit 24b-3 for the sensor heads 1-3 identified by "H001" and the cable 9 identified by "C001", and determines the distance r (m) from the magnetic field sensor position MS of the magnetic field sensor 4 to the cable center position CC. Secondly, the calculation unit 25c obtains the magnetic field data M, which is {time: "T001", magnetic field: "M001"}, {time: "T002", magnetic field: "M002"}, {time: "T003", magnetic field: "M003"}, ..., stored in the current data storage unit 24c, for the sensor heads 1-3 identified by "H001" and the cable 9 identified by "C001". Thirdly, the calculation unit 25c calculates current data A, such as {time: "T001", current: "A001"}, {time: "T002", current: "A002"}, {time: "T003", current: "A003"}, ... by substituting the distance r (m) and the magnetic field strength (A / m) indicated by the magnetic field data M into the formula H = I / (2πr) derived from Ampère's law. Fourthly, the calculation unit 25c stores the calculated current data A in the current data storage unit 24c.

[0206] Furthermore, the calculation unit 25c can also use distance data D1 output from the distance measuring sensor 6 according to Embodiment 1, distance data D2 output from the multiple magnetic field sensors 4 (41, 42, ...) according to Embodiment 2, etc.

[0207] (2-4. Example configuration and processing of Probe 5) Using Figure 15, an example of the configuration and processing of probe 5 will be explained. Probe 5 includes a detection circuit 51 and converts the detection results of the magnetic field sensor 4. For example, probe 5 converts the sensor voltage value V1 detected by the magnetic field sensor 4 into magnetic field strength (A / m). Probe 5 can also convert the sensor voltage value VW detected by the state sensor 8 into width data D3.

[0208] (2-5. Example configuration and processing of cable fastener 7) Using Figure 15, an example of the configuration and processing of the cable fixing device 7 will be explained. The cable fixing device 7 supports the conductor cable 9 and fixes it to the magnetic field shield 3 of the sensor head 1-3. For example, the cable fixing device 7 includes a clamping portion 71 that clamps the cable 9 and has a clamping width that decreases as it approaches the opening 37 of the magnetic field shield 3, and a deformation portion 72 that deforms to have a deformation amount W corresponding to the position when the cable 9 is pushed into the clamping portion 71 from the opposite side of the opening 37 and positioned.

[0209] The cable fastener 7 includes a lower contact portion 75 that contacts the cable 9 so as to push the cable 9 into the clamping portion 71 from the opposite side of the opening 37 of the magnetic field shield 3. At this time, the deformable portion 72-1 of the cable fastener 7 includes a spring 77 that biases the lower contact portion 75 toward the opening 37 of the magnetic field shield 3. The cable fastener 7 also includes a base portion 73 to which the clamping portion 71 and the deformable portion 72-2 are connected. At this time, the deformable portion 72-2 of the cable fastener 7 includes a pair of extending portions 74 that extend from the base portion 73 toward the opening 37 of the magnetic field shield 3, and as the cable 9 is pushed into the clamping portion 71, the distance between the pair of extending portions 74 of the deformable portion 72-2 changes.

[0210] [3. Flow of each process in the current measurement system 100-3] The processing flow of the current measurement system 100-3 according to Embodiment 3 will be explained using Figure 24. Figure 24 is a flowchart showing an example of the processing flow of the current measurement system 100-3 according to Embodiment 3. Note that the processes in steps S301 to S310 below can be executed in a different order. Also, some of the processes in steps S301 to S310 below may be omitted.

[0211] (3-1. Third detection data measurement process) Firstly, the current measurement system 100-3 performs the third detection data measurement process (step S301). For example, the state sensor 8 outputs width data D3 indicating the state of the cable fastener 7 as the third detection data.

[0212] (3-2. Third detection data acquisition process) Secondly, the current measurement system 100-3 performs a third detection data acquisition process (step S302). For example, the current measurement device 2-3 acquires width data D3, which indicates the state of the cable fixing device 7 output by the state sensor 8, as the third detection data.

[0213] (3-3. Third detection data storage process) Thirdly, the current measurement system 100-3 performs a third detection data storage process (step S303). For example, the current measurement device 2-3 stores the width data D3 acquired from the state sensor 8 as third detection data in the third detection data storage unit 24a-3.

[0214] (3-4. Third detection data reference processing) Fourth, the current measuring system 100-3 performs a third detection data reference process (step S304). For example, the current measuring device 2-3 refers to the width data D3 stored in the third detection data storage unit 24a-3 as the third detection data. The current measuring device 2-3 also refers to the magnetic field sensor position MS of the magnetic field sensor 4, which is a set value stored in the storage unit 24-3. The current measuring device 2-3 also refers to the fixing position CF of the cable fixing device 7, which is a set value stored in the storage unit 24-3.

[0215] (3-5. Third position data calculation process) Fifth, the current measurement system 100-3 performs a third position data calculation process (step S305). For example, the current measurement device 2-3 uses the width data D3, the magnetic field sensor position MS, and the fixing position CF of the cable fixing device 7 as third position data to calculate the cable radius d of the cable 9 and also calculates position data L3 indicating the cable center position CC of the cable 9.

[0216] (3-6. Third position data storage process) Sixth, the current measurement system 100-3 performs a third position data storage process (step S306). For example, the current measurement device 2-3 stores position data L3, which includes the calculated three-dimensional coordinates of the cable center position CC and the distance r from the magnetic field sensor position MS, as third position data in the third position data storage unit 24b-3.

[0217] (3-7. Third position data reference processing) Seventh, the current measuring system 100-3 performs a third position data reference process (step S307). For example, the current measuring device 2-3 refers to the position data L3 stored in the third position data storage unit 24b-3 as the third position data.

[0218] (3-8. Magnetic field data reference processing) Eighth, the current measurement system 100-3 performs magnetic field data reference processing (step S308). For example, the current measurement device 2-3 refers to the magnetic field data M stored in the current data storage unit 24c, which is the magnetic field strength (A / m) corresponding to the detection result of the magnetic field sensor 4.

[0219] (3-9. Current Data Calculation Process) Ninth, the current measurement system 100-3 performs current data calculation processing (step S309). For example, the current measurement device 2-3 uses position data L3 and magnetic field data M to calculate current data A, which indicates the current value (A) of the current I flowing through the cable 9 at regular intervals.

[0220] (3-10. Current Data Storage Process) Tenth, the current measurement system 100-3 performs current data storage processing (step S310) and terminates the process. For example, the current measurement device 2-3 stores the calculated current data A in the current data storage unit 24c. At this time, the current measurement device 2-3 can also display the calculated current data A as a waveform of current I on the output unit 22, which is a display.

[0221] [4. Effects of Embodiment 3] The effects of Embodiment 3 will now be described. Below, effects 1 to 4 corresponding to the processing of Embodiment 3 will be explained.

[0222] (4-1. Effect 1) First, in the process according to Embodiment 3 described above, the current measurement system 100-3 includes a magnetic field shield 3 configured to capture the magnetic field H generated by the current I flowing through the cable 9 inside, a magnetic field sensor 4 installed inside the magnetic field shield 3, a state sensor 8 that detects the state of the cable fixture 7, a current measurement device 2-3, and a cable fixture 7 that supports the cable 9 and fixes it to the magnetic field shield 3. The current measurement device 2-3 acquires the detection result of the state sensor 8, identifies the cable center position CC of the cable 9 based on the acquired detection result of the state sensor 8, and calculates the current value (A) of the current I flowing through the cable 9 based on the identified cable center position CC and the acquired detection result of the magnetic field sensor 4. Therefore, in this process, by using the state sensor 8 that detects the state of the cable fixture 7 as a predetermined sensor for detecting the cable 9, the measurement accuracy of the current I flowing through the cable 9 can be improved.

[0223] (4-2. Effect 2) Second, in the process according to Embodiment 3 described above, the cable fixture 7 includes a clamping portion 71 that has a clamping width that decreases as it approaches the opening 37 of the magnetic field shield 3 and clamps the cable 9, and a deformation portion 72 (72-1, 72-2) that deforms so as to have a deformation amount W corresponding to its position when the cable 9 is pushed into the clamping portion 71 from the side opposite to the opening 37 and positioned. The state sensor 8 detects the deformation amount W of the deformation portion 72 (72-1, 72-2). Therefore, in this process, by using the deformation amount W corresponding to the position of the cable 9 as the state of the cable fixture 7, the measurement accuracy of the current I flowing through the cable 9 can be improved.

[0224] (4-3. Effect 3) Thirdly, in the process according to the above-described Embodiment 3, the cable fixture 7 includes a lower contact portion 75 that contacts the cable 9 so as to push the cable 9 into the clamping portion 71 from the side opposite to the opening 37 of the magnetic field shield 3, and the deformation portion 72-1 includes a spring 77 that biases the lower contact portion 75 toward the opening 37. Since the state sensor 8 detects the displacement amount of the spring 77, in this process, by using the displacement amount of the spring 77 corresponding to the position of the cable 9 as the state of the cable fixture 7, the measurement accuracy of the current I flowing through the cable 9 can be improved.

[0225] (4-4. Effect 4) Fourthly, in the process according to the above-described Embodiment 3, the cable fixture 7 includes a base portion 73 to which the clamping portion 71 and the deformation portion 72-2 are connected, and the deformation portion 72-2 includes a pair of extending portions 74 that extend from the base portion 73 toward the opening 37 of the magnetic field shield 3. As the cable 9 is pushed into the clamping portion 71, the distance between the pair of extending portions 74 of the deformation portion 72-2 changes. The state sensor 8 detects the distance between the pair of extending portions 74 of the deformation portion 72-2. Therefore, in this process, by using the distance between the pair of extending portions 74 corresponding to the position of the cable 9 as the state of the cable fixture 7, the measurement accuracy of the current I flowing through the cable 9 can be improved.

[0226] [System] Regarding the processing procedures, control procedures, specific names, and information including various data and parameters shown in the above documents and drawings, they can be arbitrarily changed unless otherwise specified.

[0227] Also, each component of each device shown in the drawings is a functional concept, and it is not necessarily required to be physically configured as shown in the drawings. That is, the specific forms of dispersion and integration of each device are not limited to those shown. In other words, all or part of it can be functionally or physically dispersed and integrated in any unit according to various loads, usage situations, etc.

[0228] Furthermore, each processing function performed by each device may be implemented, in whole or in part, by a CPU and a program executed for analysis by that CPU, or by hardware using wired logic.

[0229] [Hardware] Next, an example of the hardware configuration of the current measuring device 2 (2-1, 2-2, 2-3) will be described. Note that other devices can also have a similar hardware configuration. Figure 25 shows an example of the hardware configuration according to Embodiments 1 to 3. As shown in Figure 25, the current measuring device 2 (2-1, 2-2, 2-3) includes a communication device 2a, an HDD (Hard Disk Drive) 2b, memory 2c, and a processor 2d. Furthermore, the components shown in Figure 25 are interconnected by a bus or the like.

[0230] Communication device 2a is a network interface card or the like, and communicates with other servers. HDD2b stores programs and databases that operate the functions shown in Figures 4, 11, and 21.

[0231] The processor 2d operates a process that performs the functions described in Figures 4, 11, and 21 by reading a program from the HDD 2b or the like that performs the same processing as the processing units shown in Figures 4, 11, and 21, and loading it into memory 2c. For example, this process performs the same functions as the processing units of the current measuring device 2 (2-1, 2-2, 2-3). Specifically, the processor 2d reads a program from the HDD 2b or the like that has the same functions as the acquisition unit 25a, the identification unit 25b, the calculation unit 25c, etc. Then, the processor 2d executes a process that performs the same processing as the acquisition unit 25a, the identification unit 25b, the calculation unit 25c, etc.

[0232] Thus, the current measuring device 2 (2-1, 2-2, 2-3) operates as a device that executes various processing methods by reading and executing a program. Furthermore, the current measuring device 2 (2-1, 2-2, 2-3) can also achieve the same functions as in Embodiments 1 to 3 by reading the above program from the recording medium using a media reading device and executing the read program. Note that the programs according to Embodiments 1 to 3 are not limited to being executed by the current measuring device 2 (2-1, 2-2, 2-3). For example, the present invention can be similarly applied when another computer or server executes the program, or when they cooperate to execute the program.

[0233] This program can be distributed via networks such as the Internet. Furthermore, this program can be recorded on computer-readable storage media such as hard disks, flexible disks (FDs), CD-ROMs, MOs (Magneto-Optical disks), and DVDs (Digital Versatile Discs), and executed by reading the program from these media using a computer.

[0234] 〔others〕 Some examples of the combinations of technical features that will be disclosed are listed below.

[0235] (1) A current measuring system comprising: a magnetic field shield configured to take in a magnetic field generated by an electric current flowing through a conductor; a magnetic field sensor installed inside the magnetic field shield; a predetermined sensor; and a current measuring device, wherein the predetermined sensor is a sensor for detecting the conductor; the magnetic field sensor detects a magnetic field at the installation location; and the current measuring device comprises: an acquisition unit for acquiring the detection result of the predetermined sensor and the detection result of the magnetic field sensor; an identification unit for identifying the center position of the conductor based on the acquired detection result of the predetermined sensor; and a calculation unit for calculating the current value of the electric current flowing through the conductor based on the identified center position and the acquired detection result of the magnetic field sensor.

[0236] (2) The current measuring system according to (1), wherein the predetermined sensor includes a distance measuring sensor for measuring the distance of the conductor.

[0237] (3) The current measuring system according to (2), wherein the distance measuring sensor includes a radar sensor.

[0238] (4) The current measurement system according to any one of (1) to (3), wherein the predetermined sensor includes an imaging sensor for imaging the conductor.

[0239] (5) The current measurement system according to any one of (1) to (4), wherein the magnetic field sensor is a plurality of magnetic field sensors installed at different positions from each other, the predetermined sensor includes the plurality of magnetic field sensors, the acquisition unit acquires the detection result of each of the plurality of magnetic field sensors as the detection result of the predetermined sensor, and the identification unit uses the acquired detection result of each of the plurality of magnetic field sensors to identify the center position of the conductor.

[0240] (6) The current measurement system according to (5), wherein the calculation unit calculates the current value based on the detection result of at least one magnetic field sensor among the plurality of magnetic field sensors and the identified center position.

[0241] (7) The current measuring system according to any one of (1) to (6), further comprising a fixing device that supports the conductor and fixes it to the magnetic field shield, and the predetermined sensor detects the state of the fixing device.

[0242] (8) The current measuring system according to (7), wherein the fixing device includes a clamping portion that clamps the conductor and has a clamping width that decreases as it approaches the opening of the magnetic field shield, and a deformable portion that deforms to have an amount of deformation corresponding to the position when the conductor is pushed into the clamping portion from the opposite side of the opening, and the predetermined sensor detects the amount of deformation of the deformable portion.

[0243] (9) The fixing device includes a contact portion that contacts the conductor so as to push the conductor into the clamping portion from the side opposite to the opening portion, the deformation portion includes a spring that biases the contact portion toward the opening portion, and the predetermined sensor detects the displacement amount of the spring, the current measurement system according to (8).

[0244] (10) The fixing device includes a base portion where the clamping portion and the deformation portion are connected, the deformation portion includes a pair of extending portions that extend from the base portion toward the opening portion, and as the conductor is pushed into the clamping portion, the distance between the pair of extending portions of the deformation portion changes, and the predetermined sensor detects the distance between the pair of extending portions of the deformation portion, the current measurement system according to (8) or (9).

[0245] (11) A current measurement device comprising: an acquisition unit that acquires the detection result of the conductor detected by a predetermined sensor, and acquires the detection result of the magnetic field detected at the installation position by a magnetic field sensor installed in a magnetic field shield configured to capture the magnetic field generated by the current flowing through the conductor; a specifying unit that specifies the center position of the conductor based on the acquired detection result of the predetermined sensor; and a calculating unit that calculates the current value of the current flowing through the conductor based on the specified center position and the acquired detection result of the magnetic field sensor.

[0246] (12) A current measurement method in which a computer acquires the detection result of the conductor detected by a predetermined sensor, acquires the detection result of the magnetic field detected at the installation position by a magnetic field sensor installed in a magnetic field shield configured to capture the magnetic field generated by the current flowing through the conductor, specifies the center position of the conductor based on the acquired detection result of the predetermined sensor, and calculates the current value of the current flowing through the conductor based on the specified center position and the acquired detection result of the magnetic field sensor, and executes the process.

[0247] (13) A current measurement program that causes a computer to perform the following processes: acquire detection results of a conductor detected by a predetermined sensor; acquire detection results of a magnetic field detected at the installation location by a magnetic field sensor installed in a magnetic field shield configured to take in the magnetic field generated by the current flowing through the conductor; identify the center position of the conductor based on the acquired detection results of the predetermined sensor; and calculate the current value of the current flowing through the conductor based on the identified center position and the acquired detection results of the magnetic field sensor. [Explanation of Symbols]

[0248] 1-1, 1-2, 1-3 Sensor Heads 2, 2-1, 2-2, 2-3 Current measuring device 2a Communication equipment 2b HDD 2c memory 2D processor 21 Input section 22 Output section 23 Communications Department 24-1, 24-2, 24-3 Storage section 24a-1 First detection data storage unit 24a-2 Second detection data storage unit 24a-3 Third detection data storage unit 24b-1 First position data storage unit 24b-2 Second position data storage unit 24b-3 Third position data storage unit 24c Current Data Storage Unit 25 Control Unit 25a Acquisition Department 25b Specific part 25c Calculation part 3. Magnetic field shielding 30 internal space 31 Bottom plate 32 Top plate 33, 34, 35, 36 Side panels 37 Opening 38 terminals 4, 41, 42 Magnetic field sensors 5 probes 51 Detection Circuit 6, 61, 62 Distance measuring sensors 6A Radar Sensor 6B imaging sensor 7, 7-1, 7-2 Cable fasteners 71 Clamping part 72, 72-1, 72-2 Deformed parts 73 Base 74 Extension 75 Lower contact portion 76 board 77 Springs 78 Upper contact part 8. State Sensor 9 Cables 100-1, 100-2, 100-3 Current Measurement System

Claims

1. A magnetic field shield configured to capture the magnetic field generated by the current flowing through a conductor, A magnetic field sensor installed within the aforementioned magnetic field shield, A designated sensor and A current measuring system comprising a current measuring device, The predetermined sensor is a sensor for detecting the conductor, The magnetic field sensor detects the magnetic field at the installation location, The current measuring device is An acquisition unit that acquires the detection result of the predetermined sensor and the detection result of the magnetic field sensor, A unit that identifies the center position of the conductor based on the detection results of the predetermined sensor obtained, The system includes a calculation unit that calculates the current value of the current flowing through the conductor based on the identified center position and the detection result of the acquired magnetic field sensor, Current measurement system.

2. The predetermined sensor includes a distance measuring sensor for measuring the distance of the conductor. The current measurement system according to claim 1.

3. The distance measuring sensor includes a radar sensor. The current measurement system according to claim 2.

4. The predetermined sensor includes an imaging sensor that images the conductor, The current measuring system according to any one of claims 1 to 3.

5. The magnetic field sensor is a plurality of magnetic field sensors installed at different positions from each other. The predetermined sensor includes the plurality of magnetic field sensors, The acquisition unit is, As a result of the detection of the predetermined sensor, the detection result of each of the plurality of magnetic field sensors is obtained. The specified part is, Using the detection results from each of the multiple magnetic field sensors obtained, the center position of the conductor is determined. The current measurement system according to claim 1.

6. The calculation unit described above, Based on the detection result of at least one of the plurality of magnetic field sensors and the identified center position, the current value is calculated. The current measurement system according to claim 5.

7. The current measuring system further comprises a fixing device for supporting the conductor and fixing it to the magnetic field shield, The predetermined sensor detects the state of the fixing device. The current measurement system according to claim 1.

8. The aforementioned fixing device is A clamping portion that clamps the conductor, having a clamping width that decreases as it approaches the opening of the magnetic field shield, A deformation portion that deforms to have an amount of deformation corresponding to the position when the conductor is pushed into the clamping portion from the opposite side of the opening and positioned, Includes, The predetermined sensor detects the amount of deformation of the deformed part. The current measurement system according to claim 7.

9. The fixing device includes a contact portion that contacts the conductor so as to push the conductor into the clamping portion from the opposite side of the opening, The deformation portion includes a spring that biases the contact portion toward the opening. The predetermined sensor detects the amount of displacement of the spring. The current measurement system according to claim 8.

10. The fixing device includes a base to which the clamping portion and the deformable portion are connected, The deformed portion includes a pair of extending portions that extend from the base toward the opening, As the conductor is pushed into the clamping portion, the distance between the pair of extended portions of the deformed portion changes. The predetermined sensor detects the distance between the pair of extended portions of the deformed portion. The current measuring system according to claim 8 or 9.

11. The detection result of the conductor detected by the designated sensor is obtained, A magnetic field sensor installed inside a magnetic field shield configured to capture the magnetic field generated by the current flowing through the conductor includes an acquisition unit that acquires the detection result of the magnetic field detected at the installation location, A unit that identifies the center position of the conductor based on the detection results of the predetermined sensor obtained, A calculation unit that calculates the current value of the current flowing through the conductor based on the identified center position and the detection result of the acquired magnetic field sensor, A current measuring device equipped with the following features.

12. Computers The detection result of the conductor detected by the designated sensor is obtained, A magnetic field sensor installed inside a magnetic field shield, which is configured to take in the magnetic field generated by the current flowing through the conductor, acquires the detection result of the magnetic field detected at the installation location. Based on the detection results obtained from the predetermined sensor, the center position of the conductor is determined. Based on the identified center position and the detection results of the acquired magnetic field sensor, the current value of the current flowing through the conductor is calculated. A method for measuring the current used to perform a process.

13. On the computer, The detection result of the conductor detected by the designated sensor is obtained, A magnetic field sensor installed inside a magnetic field shield, which is configured to take in the magnetic field generated by the current flowing through the conductor, acquires the detection result of the magnetic field detected at the installation location. Based on the detection results obtained from the predetermined sensor, the center position of the conductor is determined. Based on the identified center position and the detection results of the acquired magnetic field sensor, the current value of the current flowing through the conductor is calculated. A current measurement program that executes the process.

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