Ultra-wide-area current sensor measuring instrument, control panel, and power plant

Abstract

To realize "reduction of a detection error", "increase of a winding number", etc., by comprising a substantially rectangular coil in a current sensor section.SOLUTION: A current sensor measuring machine 1 comprises a current sensor section 2 which outputs a current corresponding to a current in a predetermined cable run and a measuring section 3 which measures a value, etc., of the current in the predetermined cable run on the basis of the output current from the current sensor section 2, and the current sensor section 2 includes a substantially rectangular coil 4. The substantially rectangular coil 4 is formed by abutting end faces of two substantially U-shaped core members 5 with each other. A winding wire is wound around an opposed side, a current rating range is from 15 A or more to 1,800 A or less, and a correction section 6 is included for correcting the current value measured by the measuring section 3. A relay section 7 which performs a relay operation corresponding to the measured current value, etc., and the measuring section 3 are incorporated in an identical housing 8 or a panel including the current sensor measuring machine 1 may also be provided. In a power plant 20 in which a load F or a power generation system 22 is connected to a system panel 21 connected to a system K, the current sensor section 2 includes the substantially rectangular coil 4.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a current sensor measuring device attached to a predetermined electric circuit, a panel having this current sensor measuring device, and a power plant.

Background Art

[0002] Conventionally, a current transformer has been known (see Patent Document 1). This current transformer includes a coil formed by winding a wire in a toroidal shape around the outer periphery of an annular core portion, an annular first shield plate and an annular second shield plate, and an annular case. The annular case is a member having a cross-sectional H shape including an inner cylindrical wall, an outer cylindrical wall located outside the inner cylindrical wall, and an annular connecting plate connecting between the inner cylindrical wall and the outer cylindrical wall. In an annular first storage space surrounded by one surface of the annular connecting plate, the inner cylindrical wall, and the outer cylindrical wall, the coil and the first shield plate are stacked and stored. In an annular second storage space surrounded by the other surface of the annular connecting plate, the inner cylindrical wall, and the outer cylindrical wall, the second shield plate is stored. The coil and the first shield plate are pressed and held against one surface of the annular connecting plate by a pressing and holding portion formed in the annular case, and the second shield plate is pressed and held against the other surface of the annular connecting plate.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the current transformer described in Patent Document 1 requires that the coil be annular (circular in shape), as shown in Figure 1(a), etc. Since the outer circumference of an annular coil is longer than the inner circumference, when windings are wound around the coil, the gaps between adjacent windings on the outer circumference are larger than the gaps between adjacent windings on the inner circumference. Therefore, it is difficult to wind the coil with a constant winding spacing (making it difficult to achieve a uniform winding density), resulting in a large detection error as a current transformer. Furthermore, in the current transformer described in Patent Document 1, as shown in Figure 1(b), even if the winding spacing on the annular coil is kept constant, the gap between adjacent windings becomes larger, resulting in a decrease in the number of windings and a problem in that the detection range of the current transformer becomes narrower.

[0005] In view of these points, the present invention aims to provide a current sensor measuring instrument, control panel, and power plant that achieve "reduction of detection error" and "increase in the number of turns" by having a substantially rectangular coil in the current sensor section. [Means for solving the problem]

[0006] The current sensor measuring device 1 according to the present invention is attached to a predetermined electrical circuit. Available for use A current sensor measuring device comprising a current sensor unit 2 that outputs a current corresponding to the current in a predetermined circuit, and a measuring unit 3 that measures at least the value of the current in the predetermined circuit based on the current output from the current sensor unit 2, wherein the current sensor unit 2 comprises a substantially rectangular coil 4. The substantially rectangular coil 4 is formed by butting the end faces of two substantially U-shaped core members 5 together, and the two substantially U-shaped core members 5 as a whole are substantially rectangular, and a winding is wound around each of the two substantially rectangular substantially U-shaped core members 5 on a coil bobbin 5A, and the current sensor unit 2 comprises a sensor housing 10 that houses the substantially rectangular coil 4 and has an opening in the approximate center, and the two substantially rectangular substantially U-shaped core members 5 are substantially rectangular in plan view, while the shape of the opening in the sensor housing 10 is The current sensor measuring device is approximately square in shape, has a rated current range of 15A to 1800A, and can be attached to and used in a power plant having a grid panel 21 connected to a grid K, a load F and / or a power generation system 22 connected to the grid panel 21, a main circuit M from the grid K to the load F via the grid panel 21, an instrument current transformer 21f provided in the grid panel 21, and an output circuit 21f' on the output side of the instrument current transformer 21f. Its first characteristic is this.

[0007] The second feature of the current sensor measuring device 1 according to the present invention is, A current sensor measuring device that can be attached to a predetermined electrical circuit and used, comprising a current sensor unit 2 that outputs a current corresponding to the current in the predetermined electrical circuit, and a measuring unit 3 that measures at least the value of the current in the predetermined electrical circuit based on the current output from the current sensor unit 2, wherein the current sensor unit 2 is equipped with a substantially rectangular coil 4. The aforementioned roughly rectangular coil 4 is formed by butting the end faces of two roughly U-shaped core members 5 together. The two substantially U-shaped core members 5 are substantially rectangular in shape as a whole, and the two substantially U-shaped core members 5 are substantially rectangular in shape A winding is wound around each of the opposing pairs of edges in The number of windings wound around each of the opposing pairs of edges is one, the number of turns of each winding wound around each of the opposing pairs of edges is the same, the two roughly rectangular, roughly U-shaped core members 5 have a uniform thickness, each of the roughly U-shaped core members 5 comprises a body portion 5a and branch portions 5b provided at each end of the body portion 5a, in each of the roughly U-shaped core members 5, the length of the body portion 5a is approximately the same and the length of each of the branch portions 5b is approximately the same, the current sensor measuring instrument The rated current range is 15A to 1800A, and the current sensor measuring instrument can be attached to and used in a power plant having a grid panel 21 connected to a grid K, a load F and / or a power generation system 22 connected to the grid panel 21, a main circuit M from the grid K to the load F via the grid panel 21, an instrument current transformer 21f provided in the grid panel 21, and an output circuit 21f' on the output side of the instrument current transformer 21f. It is located at the point.

[0008] A third feature of the current sensor measuring device 1 according to the present invention is the first feature described above. or 2In addition to its features, The main circuit M and the output circuit 21f' of the instrument current transformer 21f are three-phase, three-wire circuits. The current sensor measuring device can be mounted and used in the shielded portion where the electric field in two of the three wires of the main circuit M and the output circuit 21f' of the instrument current transformer 21f is shielded. It is located at the point.

[0009] The fourth feature of the current sensor measuring device 1 according to the present invention is the first feature described above. or 2 In addition to the features mentioned above, The potential of the main circuit M is the same as that of the system K, and the potential of the output circuit 21f' of the current transformer 21f is one of 110V, 220V, or 440V. Other, The measurement unit 3 includes a correction unit 6 that corrects the value of the current in the predetermined circuit measured by the measurement unit 3 based on the current output from the current sensor unit 2. You can .

[0010] The fifth feature of the current sensor measuring device 1 according to the present invention is the first feature described above. or 2 In addition to the features mentioned above, the device also includes a relay unit 7 that performs a relay operation according to the value in the predetermined circuit measured by the measurement unit 3, and both the measurement unit 3 and the relay unit 7 are housed in the same housing 8.

[0011] Due to these features, the current sensor unit 2 is equipped with a substantially rectangular coil 4. Unlike Patent Document 1, in the substantially rectangular coil 4, the length of the inner circumference and outer circumference of each side are substantially the same. Therefore, when windings are wound around each side, the gaps between adjacent windings on the inner circumference side and the gaps between adjacent windings on the outer circumference side are substantially the same. This makes it easier to wind windings at a constant winding interval around the substantially rectangular coil 4 (making it easier to achieve a uniform winding density), thereby reducing the detection error of the current sensor unit 2 ("reduction of detection error"). As a result, the number of turns that can be made around the roughly rectangular coil 4 at a constant winding interval increases ("increase in the number of turns"), which can be said to widen the rated current range of the current sensor measuring device 1. Therefore, such a current sensor measuring instrument 1 can also be called an "ultra-wide-range current sensor measuring instrument" because it has a wider rated current range (i.e., it can handle an ultra-wide range).

[0012] Furthermore, by forming a roughly rectangular coil 4 by butting the end faces of two roughly U-shaped core members 5 together, and winding the wire around each of the opposing pairs of sides of the roughly rectangular coil 4, it becomes easier to wind the wire compared to the case described in Patent Document 1, where it is difficult to wind the wire around a single, annular coil (special winding equipment is required). This allows for further reduction of detection errors and an increase in the number of windings, and can be said to realize a current sensor measuring device 1 that is more "compatible with an ultra-wide range". Furthermore, the current rating range may be set to 15A or more and 1800A or less.

[0013] Furthermore, by providing the measurement unit 3 with a correction unit 6 that corrects the current value measured by the measurement unit 3 based on the output current from the current sensor unit 2, a further reduction in detection errors can be achieved.

[0014] Furthermore, by integrating the relay unit 7, which performs relay operations according to the value measured by the measurement unit 3, into the same housing 8 as the measurement unit 3, "space saving" is achieved by integrating them into the same housing 8. Moreover, when the threshold value of the current, etc., which serves as the criterion for whether or not to perform relay operations is a very small value, if the relay and digital ammeter are separate devices, the minute errors generated by the relay and digital ammeter will differ, leading to malfunctions. However, in this invention, since the decision of whether or not to perform relay operations is made based on the current value etc. measured by the measurement unit 3, it can be said that malfunctions will not occur.

[0015] others, The panel has a panel support on which the current sensor measuring device 1 described above is installed. You can . still, in this case In this context, "panel support" includes not only the panel enclosure (box-shaped container or casing, etc.) that houses the current sensor measuring instrument 1 and other equipment installed in the panel, but also the panel frame that supports the panel. In this case, it can also be said that the current sensor measuring instrument 1 and other equipment installed in the panel are installed (mounted) on the panel frame. Therefore, In this caseThe "panel" refers not only to the so-called "panel" that houses devices such as the current sensor measuring device 1 in the panel housing so that the devices are not exposed, but also to a system (so-called "panel system") in which devices such as the current sensor measuring device 1 are attached to the panel frame body and the devices are exposed.

[0016] This case , by providing the current sensor measuring device 1 on the panel support (such as the distribution board support 31', the system board support 21', the power generation connection board support 41', etc.) of the panel (such as the distribution board 31, the system board 21, the power generation connection board 41, etc. to be described later), when retrofitting the current sensor unit 2, the measurement unit 3, etc. to the circuit in the existing system board 21, etc., it is only necessary to add a panel having the panel support, and the efficiency of the retrofitting work is improved ("improvement of the efficiency of the retrofitting work").

[0017] The power plant 20 according to the present invention is a power plant in which a system board 21 is connected to a system K, and a load F and / or a power generation system 22 is connected to the system board 21 The system comprises a current sensor measuring device 1 attached to a predetermined circuit, a main circuit M from the system K through the system panel 21 to the load F, a current transformer 21f provided in the system panel 21, and a circuit 21f' on the output side of the current transformer 21f. and has a current sensor unit 2 that outputs a current corresponding to the current in the The current sensor measuring device 1 is the predetermined circuit, and a measurement unit 3 that measures at least the current in the circuit based on the current output from the current sensor unit 2. The current sensor unit 2 includes a substantially rectangular coil 4 The substantially rectangular coil 4 is formed by butting the end faces of two substantially U-shaped core members 5 together, and the two substantially U-shaped core members 5 as a whole are substantially rectangular, and a winding is wound around each of the two substantially rectangular substantially U-shaped core members 5 on a coil bobbin 5A, and the current sensor unit 2 comprises a sensor housing 10 that houses the substantially rectangular coil 4 and has an opening in the approximate center, and the two substantially rectangular substantially U-shaped core members 5 are substantially rectangular in plan view, while the shape of the opening in the sensor housing 10 is substantially square in plan view, the rated current range of the current sensor measuring device 1 is 15A or more and 1800A or less, and the current sensor measuring device 1 is attached to either the main circuit M or the output side circuit 21f' of the instrument current transformer 21f and is characterized by the first feature. A second feature of the power plant 20 according to the present invention is that a grid panel 21 is connected to a grid K, a load F and / or a power generation system 22 is connected to the grid panel 21, and the power plant has a current sensor measuring device 1 attached to a predetermined circuit, a main circuit M from the grid K to the load F via the grid panel 21, an instrument current transformer 21f provided on the grid panel 21, and an output circuit 21f' on the output side of the instrument current transformer 21f, wherein the current sensor measuring device 1 has a current sensor unit 2 that outputs a current corresponding to the current in the predetermined circuit, and a measuring unit 3 that measures at least the current in the circuit based on the current output from the current sensor unit 2, the current sensor unit 2 comprises a substantially rectangular coil 4, the substantially rectangular coil 4 is formed by butting the end faces of two substantially U-shaped core members 5 together, and the two substantially U-shaped core members 5 as a whole are substantially rectangular The two substantially U-shaped core members 5 are roughly rectangular in shape, and windings are wound around each of the opposing pairs of sides of each of the two substantially U-shaped core members 5, with one winding wound around each of the opposing pairs of sides, and the number of turns of each winding wound around each of the opposing pairs of sides is the same, the two substantially U-shaped core members 5 are roughly rectangular in shape, and each substantially U-shaped core member 5 comprises a body portion 5a and branch portions 5b provided at each end of the body portion 5a, and in each substantially U-shaped core member 5, the length of the body portion 5a is roughly the same and the length of each branch portion 5b is roughly the same, the rated current range of the current sensor measuring device 1 is 15A or more and 1800A or less, and the current sensor measuring device 1 is attached to either the main circuit M or the output side circuit 21f' of the instrument current transformer 21f.

[0018] This ReraDue to these characteristics, even in the power plant 20, the current sensor unit 2 is equipped with a substantially rectangular coil 4. Unlike Patent Document 1, in the substantially rectangular coil 4, the length of the inner circumference and outer circumference of each side are substantially the same. Therefore, when windings are wound around each side, the gap between adjacent windings on the inner circumference side and the gap between adjacent windings on the outer circumference side are substantially the same. This makes it easier to wind winds at a constant winding interval around the substantially rectangular coil 4, thereby reducing the detection error of the current sensor unit 2 ("reduction of detection error"). As a result, the number of windings that can be wound at a constant winding interval around the substantially rectangular coil 4 increases ("increase in the number of windings"), which can be said to widen the rated current range of the current sensor measuring instrument 1. Therefore, such a power plant 20 can also be called a "power plant capable of handling an ultra-wide area" because it has a wider range of current ratings (i.e., it can handle an ultra-wide area). [Effects of the Invention]

[0019] According to the current sensor measuring device, panel, and power plant of the present invention, the current sensor section is equipped with a substantially rectangular coil, thereby enabling "reduction of detection error" and "increase in the number of turns." [Brief explanation of the drawing]

[0020] [Figure 1] This is a schematic diagram showing the current sensor measuring device (current sensor unit, measuring unit, etc.) according to the present invention. [Figure 2] This is a bottom perspective view showing the current sensor section. [Figure 3] This is a partially perspective plan view showing the current sensor section. [Figure 4] This is a front view showing the current sensor section. [Figure 5] This is a side view showing the current sensor section. [Figure 6] This is a photograph used as a substitute for a drawing, showing a perspective view of the roughly rectangular coil in the current sensor section. [Figure 7] This is a photograph used as a substitute for a drawing, showing a plan view of the roughly rectangular coil in the current sensor section. [Figure 8]This is a photograph used as a substitute for a drawing, showing a front view of the roughly rectangular coil in the current sensor section. [Figure 9] This is a photograph used as a substitute for a drawing, showing a rear view of the roughly rectangular coil in the current sensor section. [Figure 10] This is a photograph used as a substitute for a drawing, showing a side view of the roughly rectangular coil in the current sensor section. [Figure 11] The graph shows the detection results of the current sensor, where (a) shows the case when the AC current frequency is 50 Hz, and (b) shows the case when the AC current frequency is 60 Hz. [Figure 12] The graph shows the phase angle characteristics of the current sensor section, where (a) shows the case when the AC current frequency is 50 Hz, and (b) shows the case when the AC current frequency is 60 Hz. [Figure 13] This is a schematic diagram illustrating a power plant and a panel (such as a switchboard) according to the first embodiment of the present invention. [Figure 14] This is a schematic diagram illustrating a power plant and a panel (such as a switchboard) according to a second embodiment of the present invention. [Figure 15] This is a schematic diagram illustrating a power plant and a panel (such as a switchboard) according to a third embodiment of the present invention. [Figure 16] This is a schematic diagram illustrating a power plant and a panel (such as a switchboard) according to the fourth embodiment of the present invention. [Modes for carrying out the invention]

[0021] Hereinafter, embodiments of the present invention will be described with reference to the drawings. <Overall configuration of current sensor measuring device 1> Figures 1 to 16 show the current sensor measuring device 1 according to the present invention. This current sensor measuring device 1 is a device that is attached to a predetermined electrical circuit S and comprises a current sensor unit 2 and a measuring unit 3, which will be described later.

[0022] The current sensor measuring device 1 may have a measurement unit 3 equipped with a correction unit 6 (described later), or it may also have a relay unit 7 and a housing 8. Here, "attached to a predetermined circuit S" in the present invention includes cases where the device is attached to the opening of the substantially rectangular coil 4 of the current sensor unit 2, which will be described later, by passing it through circuits such as the main circuit M, branch circuit 24, and the secondary circuit 21f' of the instrument current transformer 21f, which will be described later, as well as cases where it is connected to a transformer (for example, the low-voltage side of the instrument transformer 21b, which will be described later, or the low-voltage side of the pole-mounted transformer K', etc.).

[0023] The current sensor measuring device 1 may also have an output unit (not shown) that digitizes the output current from the current sensor unit 2 (described later) and outputs it to the measuring unit 3 (described later) or the control unit 28 of the power plant 20 (described later) via a wired connection such as a communication cable 1A, or wirelessly. The current sensor measuring device 1 can have any value for the detection interval by the current sensor unit 2 or the output interval (communication speed) of the output unit described above. For example, the output interval may be 0.1 seconds or less, 0.05 seconds to 2.00 seconds, 0.75 seconds to 1.50 seconds, or 0.10 seconds to 1.00 seconds (such as 0.1 seconds).

[0024] The rated current range of such a current sensor measuring device 1 is not particularly limited, but for example, it may be 15A or more and 1800A or less, preferably 20A or more and 1650A or less, and more preferably 25A or more and 1500A or less. Here, the "rated current range" in this invention refers to the range of rated currents, and "rated current" can also be said to be the limit value of current compensated by the manufacturer for the safe use of electrical products. Furthermore, "rating" can also be said to be the usage limit or conditions under which safe and proper operation of equipment or devices is guaranteed. Furthermore, in this invention, the "current value" refers to the effective value. Furthermore, the maximum value of the current actually flowing through the current sensor measuring device 1 may be 10 to 20 times the maximum value of the current rating range mentioned above (for example, 40,000A, 36,000A, 30,000A, etc.), and the minimum value of the current actually flowing through the current sensor measuring device 1 may be 0A. Next, the current sensor unit 2 will be described below.

[0025] <Current Sensor Unit 2> As shown in Figures 1 to 16 (especially Figures 2 to 10), the current sensor unit 2 is the part that detects the current in the predetermined circuit S described above, and it can be said that the current sensor measuring device 1 has a current detection function. Here, "electrical circuit" in this invention refers to a device that carries electricity, and includes conductors such as copper, aluminum, silver, gold, and nichrome, as well as cables in which such conductors are covered with an insulator, and general electric wires.

[0026] The predetermined circuit S through which the current sensor unit 2 detects the current is not particularly limited, but may be, for example, a three-phase three-wire (3φ3W) circuit like the system K described later, a circuit through which current (alternating current) flows with a voltage of 6600V, 22000V, 3300V, etc., or a frequency of 60Hz or 50Hz, or a circuit through which current flows such as a single-phase two-wire (1φ2W) or single-phase three-wire (1φ3W). More specifically, the predetermined circuit S in which the current sensor unit 2 detects the current may be, for example, the circuit from system K to load F via system panel 21 in the power plant 20 described later (hereinafter referred to as "main circuit M"), or the branch circuit 24 described later, or it may also be the secondary circuit 21f' of the instrument current transformer 21f described later.

[0027] Furthermore, if the current sensor unit 2 is directly attached to the main circuit M, etc., or attached to the secondary circuit 21f' of the instrument current transformer 21f, etc., and the current sensor unit 2 can detect the current value of the main circuit M, etc., then the voltage value (potential) of the main circuit M, etc. will be the same potential as the system K (6600V, 22000V, 3300V, etc.). Therefore, the product of the current value of the main circuit M, etc. detected by the current sensor unit 2 and the voltage value of the main circuit M, etc. can be said to be the power in the main circuit M, etc., which is the power sold to the system K (reverse power) or the power purchased (received power) flowing from the system K, etc., as detected by the current sensor unit 2. This is also true when the current sensor unit 2 is connected to the low-voltage side of the pole-mounted transformer (step-down transformer) K'. As long as the current sensor unit 2 can detect the current value on the low-voltage side of the pole-mounted transformer K', the power will be approximately the same on both the high-voltage and low-voltage sides of the pole-mounted transformer K' (ignoring iron losses, copper losses, etc.). Therefore, the product of the current value on the low-voltage side of the pole-mounted transformer K' detected by the current sensor unit 2 and the voltage value on the low-voltage side of the pole-mounted transformer K' can be said to be the power in the system K (the power sold to the system K (reverse power) and the power purchased to the system K (received power) detected by the current sensor unit 2).

[0028] Such a current sensor unit 2 may exist as a single unit in a current sensor measuring device 1, or it may exist as a multiple unit. The current sensor unit 2 can have any configuration as long as it can detect the current in a predetermined circuit S. For example, it can be a fluxgate type (open-loop or closed-loop type), a Hall element type (open-loop or closed-loop type), a CT (Current Transformer) type, or a Rogowski coil type.

[0029] Furthermore, there are no particular limitations on the power supply for the current sensor measuring device 1, but it may be shared with the voltage of the circuit to be detected as described above (i.e., 110V, 220V, 440V at 60Hz or 50Hz, or 100V to 200V), or it may be DC 100V or 110V. The current sensor unit 2 is not particularly limited as long as it can detect current, but it may be electronic, mechanical, three-phase (a method that detects two phases out of three wires), or single-phase.

[0030] Furthermore, the current transformation ratio of the current sensor unit 2 between the primary side (the predetermined circuit S side) and the secondary side (the output from the current sensor unit 2 (sensor circuit 11) side) is not particularly limited, but for example, the minimum value may be 10:1 or 100:1, and the maximum value may be 5000:1 or 20000:1 (1500:1 or 15000:1, etc.). In other words, if the current transformation ratio between the primary and secondary sides of the current sensor unit 2 is 1500:1, even if the current flowing through the circuit to be detected is very large, for example, 1500A, the current output from the current sensor unit 2 will be approximately 1A (1000mA). If the current transformation ratio between the primary and secondary sides of the current sensor unit 2 is 15000:1, even if the current flowing through the circuit to be detected is very large, for example, 1500A, the current output from the current sensor unit 2 will be approximately 0.1A (100mA).

[0031] Furthermore, there are no particular limitations on the detectable range of the current sensor unit 2. For example, it may be 15A or more and 1800A or less, preferably 20A or more and 1650A or less, and even more preferably 25A or more and 1500A or less. It may also be 0.1A or more and 5.0A or 1A or more and 50A or less. Such a current sensor unit 2 can be installed at any position relative to a predetermined circuit S, as long as it can detect the current in that circuit. For example, it may be installed in the secondary circuit 21f' of the instrument current transformer 21f described later, or in the main circuit M from system K through the system panel 21 to the load F, or on the low-voltage side of the pole-mounted transformer K' described later.

[0032] The current sensor unit 2 described above includes a roughly rectangular coil 4, which will be described later. In addition, the current sensor unit 2 may also include a sensor housing 10 and a sensor circuit 11, which will be described later. Furthermore, the current sensor unit 2 may be of the open / close type that can be attached to the predetermined electrical circuit S without interrupting the predetermined electrical circuit S, but it does not have to be of the open / close type. Next, the roughly rectangular coil 4 in the current sensor unit 2, the sensor housing 10, and the sensor circuit 11 will be described below.

[0033] <Roughly rectangular coil 4> As shown in Figures 1-16 (especially Figures 2-10), the roughly rectangular coil 4 is a coil that is roughly rectangular in shape when viewed from above. More specifically, the roughly rectangular coil 4 may be roughly rectangular in shape (i.e., roughly rectangular) in plan view, having a pair of roughly parallel and opposing long sides and a pair of roughly parallel and opposing short sides, or it may be roughly rectangular in shape (i.e., roughly square) in plan view, having four sides of equal length (and two pairs of opposing sides).

[0034] Furthermore, the roughly rectangular coil 4 may have rounded corners when viewed from above, or it may have sharp corners when viewed from above, or it may have chamfered corners (the ends of the corners may be cut off). The roughly rectangular coil 4 may have windings only around its edges (i.e., the sides), or it may have windings around both the corners and the sides, or it may have windings only around the corners.

[0035] If a roughly rectangular coil 4 has windings around its edges, the windings may be wound around each of the four opposing pairs of edges, or around two adjacent edges, all four edges, any three edges, or any one edge. Hereafter, we will assume that the roughly rectangular coil 4 has windings wound around each of its opposing pairs of sides (that is, there are two windings wound around each roughly rectangular coil 4).

[0036] From these two wound wires, one end and the other end (so to speak, the beginning and end of the winding) may protrude as lead wires, etc. Alternatively, the ends of each winding may be connected to each other or to each other (or one end to the other) with screws or the like to create electrical conductivity, thereby connecting the two wound wires in series. Each of the two wound wires connected in series may have a connecting terminal, such as a round or open-ended type, at the end that is not connected to the other, and these connecting terminals may be color-coded, for example, red and blue.

[0037] There are no particular limitations on the size (length and width), cross-sectional shape, and thickness of the roughly rectangular coil 4, nor on the material of the winding wire, etc. However, as long as the size is such that it is not limited to the coil bobbin 5A described later (that is, with the end faces of the two roughly U-shaped core members 5 butted together), the length (for example, the length in the shorter direction) may be 6.0 cm or more and 21.0 cm or less, preferably 8.0 cm or more and 18.0 cm or less, and more preferably 10.0 cm or more and 15.0 cm or less (e.g., 11.7 cm), and the length (for example, the length in the longer direction) may be 7.0 cm or more and 22.0 cm or less, preferably 9.0 cm or more and 19.0 cm or less, and more preferably 11.0 cm or more and 16.0 cm or less (e.g., 12.0 cm). Furthermore, in the roughly rectangular coil 4, the edges around which the windings are wound may be either each of the two opposing pairs of vertical (short) edges, or each of the two opposing pairs of horizontal (long) edges.

[0038] The cross-sectional shape of the roughly rectangular coil 4 may be, for example, roughly rectangular (roughly rectangular or roughly square), or it may also be roughly circular, roughly elliptical, roughly triangular, etc. The thickness of the roughly rectangular coil 4 is such that, when the cross-sectional shape is roughly rectangular, the width in a plan view may be, for example, 0.1 cm or more and 3.0 cm or less, preferably 0.3 cm or more and 2.0 cm or less, and more preferably 0.5 cm or more and 1.5 cm or less (such as 0.8 cm), and the width in a side view (length in the vertical direction) may be 0.1 cm or more and 4.0 cm or less, preferably 0.3 cm or more and 3.0 cm or less, and more preferably 0.5 cm or more and 2.0 cm or less (such as 1.0 cm).

[0039] Furthermore, the thickness of the roughly rectangular coil 4 may be different or approximately the same in width when viewed from above and in width when viewed from the side, as described above. Also, the thickness of the roughly rectangular coil 4 may be uniform or vary along its length (for example, the thickness of the vertical sides (short sides) and the horizontal sides (long sides) may be approximately the same or different). The roughly rectangular coil 4 has a roughly rectangular opening (i.e., roughly rectangular or roughly square) inside when viewed from above. The size of this opening is not particularly limited, but for example, the vertical length (e.g., the length in the shorter direction) may be 5.0 cm or more and 20.0 cm or less, preferably 7.0 cm or more and 17.0 cm or less, and more preferably 9.0 cm or more and 14.0 cm or less (e.g., 11.0 cm), and the horizontal length (e.g., the length in the longer direction) may be 6.0 cm or more and 21.0 cm or less, preferably 8.0 cm or more and 18.0 cm or less, and more preferably 10.0 cm or more and 15.0 cm or less (e.g., 11.3 cm).

[0040] The windings wound around the roughly rectangular coil 4 can also be called electric wires, and their material can be any material or type of wire that can conduct electricity, such as polyurethane copper wire (UEW), polyester copper wire (PEW), polyamide-imide copper wire (AIW), nichrome wire, silver, gold, aluminum, etc. Furthermore, the diameter of the winding wire is not particularly limited, but it may be 0.1 mm or more and 10.0 mm or less, preferably 0.2 mm or more and 5.0 mm or less, and even more preferably 0.3 mm or more and 1.0 mm or less (such as 0.6 mm).

[0041] There are no particular limitations on the number of turns (windings) of such a winding, but the upper limit is, for example, 50,000 turns or less, preferably 25,000 turns or less, more preferably 10,000 turns or less, and even more preferably 2,000 turns or less (such as 750 or 1,000 turns). There are also no particular limitations on the lower limit of the number of turns, but for example, 10 turns or more, preferably 100 turns or more, more preferably 300 turns or more, and even more preferably 500 turns or more. The upper and lower limits for the number of turns of the winding described above can be combined with each other, for example, between 10 and 50,000 turns, or between 300 and 2,000 turns.

[0042] Furthermore, if multiple windings are provided around a single roughly rectangular coil 4, the number of turns for each winding may be the same or different. Furthermore, with respect to the number of turns of the windings in the roughly rectangular coil 4 (if there is one winding, it is the number of turns of that winding; if there are multiple windings, it is the total number of turns of those multiple windings), the predetermined circuit S that is the target of detection can be said to have 1 turn. Therefore, the current transformation ratio between the primary side (the predetermined circuit S side) and the secondary side (the output from the current sensor 2 (sensor circuit 11) side) of the current sensor unit 2 is the number of turns of the windings in the roughly rectangular coil 4 for the number of turns in the predetermined circuit S, which is 1 (i.e., 1: number of turns of the windings in the roughly rectangular coil 4).

[0043] When winding this wire, you can use a winding machine such as a spindle winding machine, a flyer winding machine, or a tracing winding machine, or you can do it by hand; any method is acceptable. Furthermore, when using a winding machine to perform aligned winding, it is necessary to apply some tension to the winding to keep it taut in order to achieve neat, aligned winding. Therefore, you may temporarily secure the beginning and end of the winding with tape or wrap it around the aforementioned retaining pins.

[0044] Such a roughly rectangular coil 4 may have two core members 5, which will be described later, and may also be equipped with a coil bobbin 5A, a fixing device 5B, etc. Furthermore, the roughly rectangular coil 4 may have only one roughly rectangular core member, and it may not have a coil bobbin 5A (i.e., the winding may be directly wound around the roughly rectangular coil 4), nor may it have a fixing device 5B, etc. Hereafter, we will assume that the roughly rectangular coil 4 has two core members 5, and we will describe these core members 5 first.

[0045] <Core component 5> As shown in Figures 1-16 (especially Figures 2-10), the core member 5 can also be described as an iron core member (magnetic core member), and the above-mentioned substantially rectangular coil 4 may be formed by two core members 5. The shape of the core member 5 is not particularly limited, but for example, each may be formed in a roughly U-shape when viewed from above. In this case, the end faces of two such roughly U-shaped core members 5 are brought together to form one of the roughly rectangular coils 4 described above.

[0046] To elaborate on this roughly U-shaped core member 5, it comprises a roughly rod-shaped (roughly square or roughly round) body portion 5a and roughly rod-shaped (roughly square or roughly round) branch portions 5b provided at both ends (left and right ends) of the body portion 5a (that is, there is one body portion 5a and two branch portions 5b), and the longitudinal direction of the body portion 5a and the longitudinal direction of each branch portion 5b are roughly perpendicular. In other words, the branches 5b extend from both the left and right ends of the longitudinal body 5a in directions perpendicular to the longitudinal direction of the body 5a, forming a roughly U-shape (horseshoe shape). Therefore, bringing the end faces of the two roughly U-shaped core members 5 together means bringing the tip faces of each branch portion 5b of each core member 5 together.

[0047] Furthermore, while the lengths of the body portions a of the two roughly U-shaped core members 5 are approximately the same, the lengths of the branches 5b may be, for example, approximately the same for both branches 5b of one roughly U-shaped core member 5 and both branches 5b of the other roughly U-shaped core member 5, or one may be longer (or shorter) than the other, or one branch 5b of one roughly U-shaped core member 5 may be longer (or shorter) than the other branch 5b. Furthermore, if one branch 5b of a roughly U-shaped core member 5 is longer than the other branch 5b, then if there are two roughly U-shaped core members 5 of the same shape, they can be joined together, with the tip surfaces of their respective branches 5b facing each other, to form a roughly rectangular coil 4.

[0048] In addition, the shape of the core member 5 may be such that one side is roughly U-shaped and the other side is roughly rod-shaped (such as roughly square rod-shaped or roughly round rod-shaped). In this case, the tip surfaces of each branch portion 5b of the roughly U-shaped core member 5 may be abutted against the side surfaces of each end of the other roughly rod-shaped core member 5 to form a single roughly rectangular coil 4. The core member 5 may be formed, for example, by laminating multiple long (tape-shaped) thin plates that are curved in a roughly U-shape (i.e., the laminated thin plates are visible in a plan view), or by laminating multiple thin plates that are roughly U-shaped (i.e., the laminated thin plates are visible in a side view).

[0049] Furthermore, if the core member 5 is made up of multiple long, thin plates laminated together, it can be said that the plates laminated on the outer periphery of the core member 5 are longer. Similarly, if the core member 5 is made up of multiple thin plates that are roughly U-shaped, it can be said that the shape of each plate is roughly the same. Furthermore, if the core member 5 is made up of multiple thin plates laminated together, these multiple thin plates may be bonded to each other with an adhesive or the like.

[0050] The material of the core member 5 may be silicon steel such as grain-oriented silicon steel or ultrathin silicon steel, electrical steel, dust materials such as iron dust, Sendust, or Permalloy, ferrite, amorphous, or Finemet (registered trademark). Furthermore, the core member 5 may be constructed by cutting out thin plates into predetermined shapes such as the elongated or roughly U-shaped forms described above, and then stacking them to give a certain thickness.

[0051] <Coil Bobbin 5A> As shown in Figures 1 to 16 (especially Figures 2 to 10), the coil bobbin 5A comprises a spool portion 5A1 into which each branch portion 5b of the core member 5 described above can be fitted, and flange portions 5A2 provided at both ends of the spool portion 5A1. The material of the coil bobbin 5A is not particularly limited, but it may be made of engineering plastics such as polyacetal or polycarbonate, or synthetic resins such as silicon resin or nylon (polyamide), or other materials such as fiber-reinforced plastic, ceramics, or wood.

[0052] The spool portion 5A1 in the coil bobbin 5A is a rectangular tubular member with a substantially square cross-section, and the opening shape and opening area inside this tube are slightly larger than or substantially the same as the cross-sectional shape and cross-sectional area of ​​the core member 5 (especially the branch portion 5b) described above. Therefore, the spool portion 5A1 is fixed to the core member 5 (branch portion 5b) by fitting, double-sided tape, adhesive, etc.

[0053] Inside this spool section 5A1, the tip surfaces of the branches 5b of the two roughly U-shaped core members 5 come into contact with each other. Therefore, two spool sections 5A1 (i.e., coil bobbins 5A) are provided for one roughly rectangular coil 4 formed by butting the end faces of two roughly U-shaped core members 5 together. As described above, it can also be said that a coil bobbin 5A is placed on each of the opposing pairs of sides of the roughly rectangular coil 4 (the sides formed by butting the end faces of the two roughly U-shaped core members 5 together).

[0054] The wire will be wound around the outer surface of the spool section 5A1, but the wound wire may be further wrapped with vinyl tape or the like. Furthermore, the open end of the spool portion 5A1 may abut against the curved corner of the roughly U-shaped core member 5 to position the coil bobbin 5A relative to the core member 5, thereby defining the insertion depth of each branch portion 5b into the spool portion 5A1.

[0055] The flange portion 5A2 in the coil bobbin 5A is a pair of substantially square, flat plate-like members integrally provided at the upper and lower ends of the spool portion 5A1 described above, and each flange portion 5A2 is arranged perpendicular to the axis of the spool portion 5A1, that is, each side faces substantially towards the front or back. Furthermore, each flange portion 5A2 may abut against a curved corner of the roughly U-shaped core member 5 to position the coil bobbin 5A relative to the core member 5, and the insertion depth of each branch portion 5b into the spool portion 5A1 may also be defined.

[0056] In addition, the flange portion 5A2 may be provided with a retaining pin for securing the winding at the beginning or end of winding onto the spool portion 5A1, and a guide groove may be provided to guide the winding when securing it to the retaining pin. There are no particular limitations on the number of these locking pins and guide grooves, but for example, if two locking pins are provided, a protrusion may be provided between the two locking pins (approximately in the middle position) to hook the wire and change the winding direction.

[0057] <Fixing fixture 5B> As shown in Figures 1-16 (especially Figures 2-10), the fastener 5B maintains (or maintains or fixes) the state in which the end faces of the two roughly U-shaped core members 5 described above are abutted against each other. The fastener 5B is not particularly limited in its configuration, but may be, for example, a cable tie. If the shape and area of ​​the opening inside the cylinder of the spool portion 5A1 of the coil bobbin 5A described above are substantially the same as the cross-sectional shape and cross-sectional area of ​​the core member 5 (especially the branch portion 5b) (in other words, the branch portion 5b of the core member 5 fits tightly into the spool portion 5A1 of the coil bobbin 5A), then the coil bobbin 5A can also be said to be the fastener 5B.

[0058] Hereafter, fastener 5B will be described primarily as a cable tie. The fastener 5B, which is a cable tie, comprises a band portion 5B1 that surrounds the outer circumferential surfaces of the two roughly U-shaped core members 5 in the butted state described above, and a fastening portion 5B2 that fastens both ends of the band portion 5B1 together.

[0059] The band portion 5B1 of the fastener 5B is a band-shaped member, and its width (band width) may be approximately the same as, or slightly narrower than, the width (length in the vertical direction) of the substantially rectangular coil 4 (core member 5) in a side view, and its length (band length) may be approximately the same as, or slightly larger than, the outer circumference length of the substantially rectangular coil 4. Furthermore, if the length of the band portion 5B1 is approximately the same as the outer circumference of the roughly rectangular coil 4, the band portion 5B1 can be said to be substantially aligned with the outer surface of the roughly rectangular coil 4 (subtly in contact with it along the entire circumference without any gaps). However, if the length of the band portion 5B1 is slightly greater than the outer circumference of the roughly rectangular coil 4, the band portion 5B1 may have a slight gap between it and the outer surface of the roughly rectangular coil 4 with respect to one of the four sides of the roughly rectangular coil 4 (for example, the side where the binding portion 5B2 described later is located), but it may be substantially aligned with the outer surface of the roughly rectangular coil 4 with respect to the other three sides.

[0060] Furthermore, a portion of the band portion 5B1, along with the core member 5 (branch portion 5b), is fitted into the spool portion 5A1 of the coil bobbin 5A described above. In this way, the band portion 5B1, which is fitted into the spool portion 5A1 together with the core member 5, is held in a state that is substantially aligned with the outer surface of the substantially rectangular coil 4 by the fastening portion 5B2, which will be described later. As a result, the state in which the tip surfaces of each branch portion 5b of the two substantially U-shaped core members 5 are abutted against each other is maintained inside the spool portion 5A1.

[0061] The thickness (band thickness) and material of the band portion 5B1 are not particularly limited, but the thickness may be, for example, 0.1 mm or more and 1.0 mm or less, preferably 0.1 mm or more and 0.8 mm or less, and more preferably 0.1 mm or more and 0.5 mm or less (such as 0.3 mm). The material of the band portion 5B1 may be metal such as stainless steel, or synthetic resin.

[0062] The fastening portion 5B2 of the fastener 5B is a member that maintains the state in which the band portion 5B1 described above is substantially aligned with the outer surface of the substantially rectangular coil 4. The binding portion 5B2 is not particularly limited in its configuration, but for example, it may be a flat cylindrical member through which the band portion 5B1 can be inserted and which has a cross-sectional shape substantially similar to that of the band portion 5B1, or it may be a substantially square-shaped member in the center. In particular, the flat cylindrical member may be formed by bending a long (tape-like) thin sheet into a flat cylindrical shape, or by crushing a pipe material with a substantially circular cross-section into a flat cylindrical shape.

[0063] Hereafter, the binding portion 5B2 will be described as mainly being a flat, cylindrical member. The binding portion 5B2, which is a flat, cylindrical member, may have any length (cylinder length), width (cylinder width), thickness (cylinder thickness), or material in its outer shape. However, the length of the outer shape may be, for example, 0.1 cm or more and 3.0 cm or less, preferably 0.3 cm or more and 2.0 cm or less, and more preferably 0.5 cm or more and 1.5 cm or less (1.0 cm, for example). The length of the outer shape can be said to be the same as the length of its opening (cylinder hole).

[0064] The width of the outer shape of the binding portion 5B2 is greater than the width of the band portion 5B1 (that is, it is the width of the band portion 5B1 plus the gap between the band portion 5B1 and the binding portion 5B2 and the thickness of the tube described later), for example, it may be 0.1 cm or more and 3.0 cm or less, preferably 0.3 cm or more and 2.0 cm or less, and more preferably 0.5 cm or more and 1.5 cm or less (1.0 cm, etc.). The thickness of the outer shape is also greater than the thickness of the band portion 5B1 (that is, it is the thickness of the band portion 5B1 plus the gap between the band portion 5B1 and the binding portion 5B2 and the thickness of the tube described later), for example, it may be 0.1 mm or more and 10.0 mm or less, preferably 0.5 mm or more and 8.0 mm or less, and more preferably 1.0 mm or more and 6.0 mm or less (3.0 mm, etc.). The material of the binding portion 5B2 may be, for example, a metal such as iron, or it may be plated with nickel or other materials, or it may be made of synthetic resin or other materials.

[0065] Furthermore, the size (width and vertical length) of the opening (hole) of the binding portion 5B2, which is a flat, cylindrical member, and the wall thickness of the cylinder (wall thickness) are not particularly limited. However, the width of the hole (hole width) can be said to be slightly larger than the width of the band portion 5B1, for example, 0.1 cm or more and 3.0 cm or less, preferably 0.3 cm or more and 2.0 cm or less, and more preferably 0.5 cm or more and 1.5 cm or less (1.0 cm, etc.). The vertical length of the hole (hole vertical length) can be said to be slightly larger than the thickness of the band portion 5B1, for example, 0.1 mm or more and 5.0 mm or less, preferably 0.5 mm or more and 4.0 mm or less, and more preferably 0.7 mm or more and 3.0 mm or less (1.5 mm, etc.). The thickness of the cylindrical part 5B2, which is a flat cylindrical member (this can also be called the cylindrical wall thickness, or the thickness of the elongated thin plate that forms the flat cylindrical member), may be, for example, 0.1 mm or more and 2.0 mm or less, preferably 0.2 mm or more and 1.5 mm or less, and more preferably 0.3 mm or more and 1.0 mm or less (such as 0.6 mm).

[0066] The fastener 5B, which is a cable tie as described above, maintains the state in which the end faces of the two roughly U-shaped core members 5 are abutted against each other by the band portion 5B1 and the fastening portion 5B2 described above. This hold is, for example, <1> While unwinding from the rolled band portion 5B1, one end of the band portion 5B1 is passed through the flat, cylindrical binding portion 5B2 from one opening to the other, so that it protrudes from the other opening by a predetermined length (for example, the length of the binding portion 5B2). <2> One end of the protruding band portion 5B1 is bent from the other opening of the fastening portion 5B2 toward the other opening. <3> With one end of the band portion 5B1 passed through the fastening portion 5B2 and bent, the band portion 5B1 is further unwound for a length longer than one full circumference of the outer circumferential surface of the two roughly U-shaped core members 5 that are butted together, so that the band portion 5B1 is roughly aligned with the outer circumferential surface of the core members 5. <4> With the band portion 5B1 roughly aligned, cut the band portion 5B1 so that its length is longer than one full circumference of the outer surface of the core member 5, and detach it from the unwound band portion 5B1. <5> The detached end (the other end) is passed through the binding portion 5B2 from the other opening to the one opening, so that it protrudes from the one opening by a predetermined length (for example, the length of the binding portion 5B2). <6> While pulling the other end of the protruding band portion 5B1, the band portion 5B1 can be used to tighten the two roughly U-shaped core members 5, and the other end of the band portion 5B1 can be bent from one opening to the other of the fastening portion 5B2 to hold it in place. Furthermore, this retention is as described above. <4> ~ <6> Instead of pulling the other end of the band 5B1 after detaching it from the unwound band 5B1 and then tightening the two roughly U-shaped core members 5 with the band 5B1, it is also acceptable to pull the other end of the band 5B1 while tightening the two roughly U-shaped core members 5 with the band 5B1 and then detaching it from the unwound band 5B1.

[0067] To explain this holding in detail, <1'>While unwinding from the band portion 5B1 which has been wound into a roll shape, one end of the band portion 5B1 is passed through the flat cylindrical binding portion 5B2 from one opening to the other, <2'>Furthermore, a length longer than one circumference of the outer surface of the two roughly U-shaped core members 5 which are butted together is unwound, so that the band portion 5B1 is roughly along the outer surface of the core members 5, <3'>One end of the band portion 5B1 is passed through the binding portion 5B2 from one opening to the other, so that it protrudes from the other opening by a predetermined length (for example, the length of the cylinder of the binding portion 5B2), <4'> One end of the protruding band portion 5B1 is bent from the other opening of the fastening portion 5B2 toward the other opening, <5'> While pulling the portion of the band portion 5B1 that is wound up into a roll, the band portion 5B1 is tightened around the two roughly U-shaped core members 5, and the band portion 5B1 is cut at a point that protrudes from the one opening by a predetermined length (for example, the length of the fastening portion 5B2), separating it from the unwound band portion 5B1, <6'> The separated end (other end) may be held in place by bending it from the one opening of the fastening portion 5B2 toward the other opening. As mentioned above <1> ~ <6> In any of the holding methods such as <1'> to <6'>, when the band portion 5B1 is positioned substantially along the outer surface of the core member 5, it can be said that the band portion 5B1 is inserted into the inside of the coil bobbin 5A (spool portion 5A1), and the core member 5 (branch portion 5b) is also fitted into the inside of the coil bobbin 5A (spool portion 5A1).

[0068] <Sensor housing 10> As shown in Figures 1 to 16 (especially Figures 2 to 10), the sensor housing 10 is a housing that houses (incorporates) the above-mentioned substantially rectangular coil 4. The material of the sensor housing 10 is not particularly limited, but like the material of the coil bobbin 5A mentioned above, it may be made of engineering plastics such as polyacetal or polycarbonate, or synthetic resins such as silicon resin or nylon (polyamide), or other materials such as fiber-reinforced plastic, ceramics, or wood.

[0069] The sensor housing 10 is not particularly limited in terms of its shape, size, or configuration. For example, its shape may be roughly rectangular (roughly rectangular or roughly square) with an opening in the approximate center when viewed from above, or it may be equipped with lids 10a and 10b that enclose a roughly rectangular coil 4 sandwiched from above and below. In particular, the sensor housing 10 may have an outer periphery that is roughly rectangular in plan view, while its opening shape (so to speak, its inner periphery) may be roughly square. Alternatively, its outer periphery may be roughly rectangular in plan view, and its opening shape may also be roughly rectangular; its outer periphery may be roughly square in plan view, and its opening shape may also be roughly square; or its outer periphery may be roughly square in plan view, and its opening shape may also be roughly rectangular.

[0070] Hereafter, the shape of the sensor housing 10 will be described assuming that its outer periphery is roughly rectangular in plan view, and its opening is roughly square. Regarding the size of the sensor housing 10, the vertical length of the outer periphery (for example, the length in the shorter direction) may be 7.0 cm or more and 22.0 cm or less, preferably 9.0 cm or more and 19.0 cm or less, and more preferably 11.0 cm or more and 16.0 cm or less (e.g., 13.65 cm), and the horizontal length of the outer periphery (for example, the length in the longer direction) may be 11.0 cm or more and 26.0 cm or less, preferably 13.0 cm or more and 23.0 cm or less, and more preferably 15.0 cm or more and 20.0 cm or less (e.g., 16.0 cm).

[0071] The width (vertical length) of the sensor housing 10 in a side view may be 1.0 cm or more and 6.0 cm or less, preferably 1.5 cm or more and 5.0 cm or less, and more preferably 2.0 cm or more and 4.0 cm or less (such as 2.7 cm). Furthermore, since the approximate center portion in the longitudinal direction of the sensor housing 10 houses the coil bobbin 5A mentioned above, its vertical length may be smaller than other parts (i.e., it may be recessed). For example, it may be 0.5 cm or more and 5.5 cm or less, preferably 1.0 cm or more and 4.5 cm or less, and even more preferably 1.5 cm or more and 3.5 cm or less (such as 2.3 cm).

[0072] The depth of the recess in the approximate center of the longitudinal direction of the sensor housing 10 is not particularly limited, but may be, for example, 0.1 cm or more and 3.0 cm or less, preferably 0.1 cm or more and 2.0 cm or less, and more preferably 0.2 cm or more and 1.0 cm or less (e.g., 0.4 cm). The width of the recess (length in the longitudinal direction) is also not particularly limited, but may be, for example, 5.0 cm or more and 20.0 cm or less, preferably 7.0 cm or more and 17.0 cm or less, and more preferably 9.0 cm or more and 14.0 cm or less (e.g., 9.9 cm). If the sensor housing 10 has an opening shape (inner circumference shape) that is approximately square, the length of each side may be, for example, 5.0 cm or more and 20.0 cm or less, preferably 7.0 cm or more and 17.0 cm or less, and more preferably 9.0 cm or more and 14.0 cm or less (such as 10.5 cm).

[0073] In addition, the sensor housing 10 may be fixed by means of fastening the lid portion 10a and the bottom portion 10b described above using screws, adhesive, fitting, or other fastening methods. The lead wires and connection terminals of the roughly rectangular coil 4 described above may be exposed from the sensor housing 10, and these lead wires can be said to be part of the sensor circuit 11 described later. Furthermore, the ends of the lead wires may have a strip portion of a predetermined length (for example, 6 mm) (a portion in which the internal circuit (copper wire, etc.) is exposed), and two lead wires may be twisted together, and there are no particular limitations on this twist pit.

[0074] <Sensor circuit 11> As shown in Figures 1 to 16 (especially Figures 2 to 10), the sensor circuit 11 is a circuit that connects the current sensor unit 2 described above with the measurement unit 3, which will be described later. The value of the current flowing through this sensor circuit 11 and output from the current sensor unit 2 does not have any particular limitations, but it is related to the current transformation ratio between the primary and secondary sides of the current sensor unit 2 as described above (that is, the number of turns of the winding as the entire roughly rectangular coil 4 (if there is one wound winding, it is the number of turns of that winding, and if there are multiple wound windings, it is the total sum of the number of turns of those multiple windings)), and may be, for example, 2A or less.

[0075] In other words, the upper limit of the output current is, for example, 2A (2000mA) or less, preferably 1000mA or less, more preferably 500mA or less, and even more preferably 100mA or less (such as several hundred mA, several tens of mA, 1mA to 50mA or less). On the other hand, there are no particular limitations on the lower limit of the output current, but for example, it may be 0.01 mA or more, preferably 0.10 mA or more, more preferably 0.20 mA or more, and even more preferably 0.30 mA or more.

[0076] The upper and lower limits of the output current described above may be combined with each other, for example, 0.01mA to 2000mA or 0.01mA to 1000mA. Based on the current value flowing through this sensor circuit 11, the current sensor unit 2 detects the current value flowing through a predetermined circuit S that is the target of detection. The mounting of the current sensor unit 2, which has the roughly rectangular coil 4 described above, will be explained below.

[0077] <Installation of the current sensor unit 2 to a predetermined circuit S (main circuit M, etc.)> As shown in Figures 14 and 15, the current sensor unit 2 may be installed on two of the three wires if the predetermined circuit S to be detected is a three-phase three-wire (3φ3W) main circuit M or branch circuit 24 with voltages such as 6600V, 22000V, or 3300V, or a circuit with voltages such as 110V, 220V, or 440V that has passed through a pole-mounted transformer K' (which may also include the secondary circuit 21f' of the instrument current transformer 21f). In this case, naturally, one current sensor measuring device 1 will have two current sensor units 2.

[0078] Here, the current sensor unit 2 is installed not near the exposed terminal portion of each of the three cables of the main circuit M, but rather in the portion where the electric field is shielded (shielded) by passing through the electric field mitigation portion from the terminal portion. Furthermore, the length of the electric field mitigation section from the terminal portion of the cable varies depending on the voltage value of the cable. For example, it will be longer for high-voltage cables such as 6600V, 22000V, and 3300V, and shorter for low-voltage cables such as 110V, 220V, 440V, or between 100V and 200V.

[0079] Furthermore, there are no particular limitations on the actual thickness of each cable. For example, a high-voltage cable may be 38 sq mm (including the insulation coating made of polyvinyl chloride resin, the thickness is approximately 13.0 mm), while a low-voltage cable may be 100 sq mm (similarly including the insulation, the thickness is approximately 19.5 mm). Up to this point, the predetermined electrical circuit S that the current sensor unit 2 is supposed to detect has been a three-phase three-wire (3φ3W) circuit. However, if it is a single-phase three-wire (1φ3W) circuit, the current sensor unit 2 may be attached to two of the three wires, and if it is a single-phase two-wire (1φ2W) circuit, the current sensor unit 2 may be attached to one of the two wires.

[0080] <Detection results and phase angle characteristics of current sensor unit 2> Figures 11 and 12 show the detection results and phase angle characteristics of the current sensor unit 2 described above. Furthermore, the results shown in Figures 11 and 12 were obtained by creating 20 current sensor units 2, each with a total of 1500 turns in a roughly rectangular coil 4. For each of these 20 current sensor units 2, the frequency of the AC current to be detected (input current) was set to 50Hz or 60Hz, and the input currents were 50.00A, 40.00A, 37.50A, 30.00A, 25.00A, 24.00A, 20.00A, 18.75A, 16.00A, 15.00A, 12.50A, 12.00A, 10.00A, 8.000A, 7.500A, and 6. For currents of 000A, 5,000A, 4,000A, 3,750A, 3,000A, 2,500A, 2,000A, 1,500A, 1,000A, and 0.750A, the ratio error (%) and phase difference were calculated from the difference between the reference value (1 / 1500th of each input current, based on 1500 turns) and phase of the current output from each current sensor unit 2 and the detected value (measured value) of the current actually output from each current sensor unit 2 (output current), and the phase difference. The average values ​​of the ratio error and phase difference for 20 current sensor units 2 were then calculated.

[0081] As shown in Figure 11, the current sensor unit 2 exhibits a correlation between the input current value (reference value) and the detected output current, regardless of whether the frequency of the AC current to be detected is 50Hz or 60Hz. In particular, for input current values ​​from 50.00A (reference value 33.33mA) to predetermined values ​​(for example, 7.500A (reference value 5.00mA), 5.000A (reference value 3.33mA), and 3.000A (reference value 2.00mA)), it can be said that the ratio error between the reference value and the detected value for all current sensor units 2 is approximately 1% or less. Furthermore, for input current values ​​from the predetermined values ​​mentioned above to 0.750A (reference value 0.50mA), although the ratio error between the reference value and the detected value exceeds 1%, all current sensor units 2 tend to produce detected values ​​smaller than the reference value. Therefore, in this range where smaller values ​​occur, it is possible to compensate using the correction unit 6 described later (that is, it can handle a very wide range (ultra-wide range) of input current from 50.00A to 0.750A (the minimum value of the rated range is approximately 1 / 50th of the maximum value)). In Figure 11, the numbers in black circles indicate the number of current sensor units 2 out of 20 that exhibited the ratio error. The number of units with a ratio error of around 5% (4% or about 6%) relative to the smallest input current of 0.750A (reference value 0.50mA) was "17 units" when the frequency of the detected AC current was 50Hz and "19 units" when it was 60Hz. Regardless of the frequency, the majority of the ratio errors were at most around 5%. Conversely, "3 units" when the frequency was 50Hz and "1 unit" when it was 60Hz were exceptional. Excluding these exceptional cases, the average ratio error in the current sensor unit 2 at the smallest input current of 0.750A (reference value 0.50mA) can be said to be about "5%". Furthermore, if the input current to the current sensor unit 2 is multiplied by 30 (for example, 50A becomes 1500A, and 0.75A becomes 22.5A), the corresponding reference values ​​will also be multiplied by 30, but the ratio error of the detected value to the reference value will not change from the detection results shown in Figure 11.

[0082] As shown in Figure 12, the current sensor unit 2 exhibits a small difference in phase angle between the input current value (reference value) and the detected value, regardless of whether the frequency of the AC current to be detected is 50Hz or 60Hz. Note that the unit of the vertical axis in the graph in Figure 12 is "′ (minutes)", which is 1 / 60th of the angle unit "° (degrees)". In particular, for input current values ​​from 50.00A to 5.000A (reference values ​​from 33.33mA to 3.33mA), the difference in phase angle between the reference value and the detected value is approximately 60 minutes (1 degree) or less for all current sensor units 2. Furthermore, for input current values ​​from 5.000A to 0.750A (reference values ​​from 3.33mA to 0.50mA), although the difference in phase angle between the reference value and the detected value exceeds 60 minutes (1 degree), the phase angle of the detected value tends to be larger than the phase angle of the reference value for all current sensor units 2, and the difference in phase angle tends to be within 180 minutes (3 degrees). Therefore, it can be said that the phase angle can also be handled by correcting it in the correction unit 6 described later, within this range of larger values.

[0083] <Measurement Unit 3> As shown in Figure 1, the measurement unit 3 is the part that measures at least the value of the current in a predetermined circuit S based on the current output from the current sensor unit 2 described above. The measurement unit 3 may also include a correction unit 6, which will be described later.

[0084] The measurement unit 3 may be built into (or provided within) the housing 8, which will be described later. The measurement unit 3 is not particularly limited in its configuration, but for example, it may be equipped with an A / D converter, a CPU (central processing unit) that calculates and processes the value of the current output from the A / D converted current sensor unit 2, memory, and an LCD (liquid crystal display) as described later. In addition, the measurement unit 3 may be equipped with an auxiliary CT (auxiliary current transformer) between the current sensor unit 2 and the A / D converter and CPU, or it may not be equipped with an auxiliary CT. Furthermore, if the measurement unit 3 is equipped with an auxiliary CT, there are no particular limitations on the current transformation ratio between the primary side (input from the current sensor unit 2 (sensor circuit 11) side) and the secondary side (A / D converter side or CPU side) of the auxiliary CT. For example, the minimum value may be 2:1 or 3:1, and the maximum value may be 50:1 or 30:1 (10:1 or 20:1, etc.).

[0085] The measuring unit 3 measures at least the value of the current in a predetermined circuit S. In addition to the value of the current, if the measuring unit 3 (current sensor measuring device 1) is also connected to the low-voltage side of the instrument transformer 21b or the low-voltage side of the generator transformer 35, which will be described later, it may also measure the voltage and power values ​​in the predetermined circuit S, or measure reactive power, power factor, energy, reactive energy, etc. In addition, the measurement unit 3 may also measure the frequency of the alternating current at a predetermined power level, or the zero-sequence current.

[0086] <Correction Section 6> As shown in Figures 1 and 11, the correction unit 6 is provided in the measurement unit 3 described above and corrects the value of the current in a predetermined circuit S measured by the measurement unit 3 based on the current output from the current sensor unit 2 described above. The correction unit 6 is not particularly limited in its correction, but for example, as described above in Figure 11, the value of the current output from the current sensor unit 2 (detected value) tends to be smaller than the reference value. Within the range in which this smaller value occurs, the measurement unit 3 may perform a correction to set the measured value to a value corresponding to the ratio error (such as the value obtained by multiplying the detected value by the reciprocal of the average value of the ratio error in Figure 11 (which may be the average value excluding exceptional cases)).

[0087] Here, for the range in which the detected value from the current sensor unit 2 is smaller than the reference value, for example, in Figure 11 above, the above-mentioned correction may be performed in all ranges other than 0% where the ratio error is 0%, or the measurement unit 3 may be corrected to use a value corresponding to the ratio error only when the input current value is less than or equal to the predetermined value mentioned above (for example, 7.500A (reference value 5.00mA), 5.000A (reference value 3.33mA), or 3.000A (reference value 2.00mA)). Furthermore, the range in which the detected value from the current sensor unit 2 is smaller than the reference value may be defined as follows: for example, in the range where the input current value is between 0.750A (reference value 0.50mA) and less than 3.000A (reference value 2.00mA), the ratio error changes linearly (linearly) from 5.0% to 1.5%; in the range where the input current value is between 3.000A (reference value 2.00mA) and less than 5.000A (reference value 3.33mA), the ratio error changes linearly (linearly) from 1.5% to 1.0%; and in the range where the input current value is between 5.000A (reference value 3.33mA) and 50.00A (reference value 33.33mA), the ratio error changes linearly (linearly) from 1.0% to 0.0%. In this range in which a small value occurs, the measurement unit 3 may correct the value measured by the measurement unit 3 to a value corresponding to that ratio error.

[0088] Alternatively, the correction performed by the correction unit 6 may be a correction in which the value obtained by first-order scaling of the detected value is used as the value measured by the measurement unit 3. The correction unit 6 does not have any particular limitations in its configuration, but for example, the correction performed by the correction unit 6 may be calculated and processed by the CPU in the measurement unit 3 described above, and can therefore be considered software.

[0089] <Relay section 7> As shown in Figure 1, the relay unit 7 is the part that performs relay operations according to the value (value such as current value) in a predetermined circuit S measured by the measurement unit 3 described above, and it can be said that the current sensor measuring device 1 has a relay function. Here, in this invention, "according to the value in the predetermined circuit S measured by the measurement unit 3" means that when the measured current, etc., becomes greater than or equal to a predetermined value (threshold) (exceeds the threshold) or becomes less than or equal to a predetermined value (threshold) (falls below the threshold), the relay operation described later will be performed.

[0090] Furthermore, the threshold values, such as current values, may include not only currents such as overcurrent, instantaneous overcurrent, and ground fault overcurrent, but also other values ​​such as voltage values ​​such as undervoltage, power values ​​such as reverse power, and frequency values. Furthermore, "according to the value in the predetermined circuit S measured by the measurement unit 3" includes not only cases where the relay operation described later is performed immediately after the measured current value or other value exceeds a predetermined value (threshold), but also cases where the next relay operation is performed after a predetermined time has elapsed.

[0091] Furthermore, the specified time may be 0.1 seconds or more and 15.0 seconds or 0.2 seconds or more and 5.0 seconds or more, 0.5 seconds or more, or 3.0 seconds or more (such as 2.0 seconds) after the threshold is exceeded or fallen below the threshold (that is, if 2.0 seconds or so have elapsed after the threshold is exceeded, the relay operation described later may be performed). In addition, this specified time may be adjustable in 0.1-second steps (0.0 seconds, 0.1 seconds, 0.2 seconds...15.0 seconds) from 0.0 seconds to 15.0 seconds. Furthermore, in the present invention, "relay operation" means, for example, in the power plant 20 described later, an operation to interrupt the circuit from the power generation system 22 to the grid K via a signal using one of the circuit breakers, or, if the power generation system 22 has a power conditioner 26 (a power conditioner 26 that converts DC current or AC current to AC current), stopping the conversion of said power conditioner 26.

[0092] The signals from the relay unit 7 may include, in addition to the "trip" signal (a signal to interrupt the circuit breaker) to the circuit breaker as described above, an "on" signal (a signal to turn the circuit breaker itself ON), an "off" signal (a signal to turn the circuit breaker itself OFF), and a signal to release the interruption of a predetermined circuit S. Furthermore, the signal from the relay unit 7 may include a signal to stop the conversion of the power conditioner 26, or a signal to start the conversion of the power conditioner 26.

[0093] Furthermore, the circuit breaker may be configured to trip via a tripping coil or the like based on a signal from the control unit 28 (or current sensor measuring device 1), which will be described later. The relay unit 7 is not particularly limited in its configuration, but may be a contact-type (electromagnetic) relay using an electromagnet, or a contactless relay using a semiconductor element. Furthermore, if it is an electromagnetic relay, it may be a make-type (a-contact that closes when current is passed through the electromagnet), a break-type (b-contact that opens when current is passed through the electromagnet), a transfer-type (c-contact that switches multiple contacts by passing current through the electromagnet), a ratchet-type (which switches the opening and closing of the contacts each time current is passed through the electromagnet), or any other type of polarized relay with a permanent magnet in parallel with the electromagnet.

[0094] Such a relay unit 7 may exist as only one (one element) in a single current sensor measuring device 1, but it may also exist as multiple (multiple elements). Hereafter, we will assume that there are mainly multiple relay units 7 in a single current sensor measuring device 1.

[0095] <Enclosure 8> As shown in Figure 1, the housing 8 is a housing that incorporates at least the measuring unit 3. The housing 8 can be said to be a measurement housing 8 when the current sensor measuring device 1 has a measurement unit 3 but does not have a relay unit 7, and can also be said to be a measurement relay housing 8 when the current sensor measuring device 1 has both a measurement unit 3 and a relay unit 7.

[0096] The housing 8 may be provided with a display unit, such as an LCD (liquid crystal display), that displays values ​​such as the current value measured by the measurement unit 3, and this display unit may be provided with a backlight. The information displayed on the display unit may include not only the current value measured by the measurement unit 3, but also voltage, power, or numbers representing the mode or status.

[0097] Furthermore, the housing 8 may have an operating section, and there are no particular limitations on the configuration, function, or location of this operating section; for example, it may have multiple buttons. The functions of the control panel may include, for example, a button to turn the display on and off (display button), a reset button to reset the current sensor measuring device 1, buttons to select a mode or state (such as a "+" button or a "-" button), or a set button to confirm (set) the selected mode, etc. The position of such an operating unit may also be, for example, located on the front of the housing 8, below the display unit mentioned above.

[0098] The enclosure 8 may have terminal sections (terminal blocks), and there are no particular limitations on the number or position of these terminal sections. For example, one enclosure 8 may have one terminal section or multiple terminal sections (such as three). The terminal section may also be located, for example, in the lower half of the back of the housing 8. The aforementioned measurement unit 3 and relay unit 7 are built into this single housing 8.

[0099] <Power plant 20 of the first embodiment> Figure 13 shows a power plant 20 according to the present invention. This power plant 20 has a grid panel 21, which will be described later, and the current sensor measuring device 1 mentioned above. Furthermore, this power plant 20 of the first embodiment can be described as a CB receiving type (a type equipped with a high-voltage circuit breaker (VCB) 21a) that receives high voltage power with a capacity exceeding 300 kVA. Furthermore, in the first embodiment, the current sensor unit 2 of the current sensor measuring device 1 may be directly attached to the main circuit M from system K to load F (in particular, the circuit between the instrument transformer 21h and system K within the system panel 21), or it may be attached to the output side (secondary side) circuit 21f' of the instrument transformer 21f within the system panel 21 (see the dotted line in Figure 13).

[0100] The power plant 20 may also have a load F and / or a power generation system 22, which will be described later. In other words, the grid panel 21 described above can be said to be connected to two things, grid K and load F, or to two things, grid K and power generation system 22, or to three things, grid K, load F and power generation system 22. Here, we will first describe grid K below.

[0101] <System K> As shown in Figure 13, etc., System K, also known as the commercial power system, is an integrated system of power generation, transformation, transmission, and distribution for supplying electricity to the receiving equipment of consumers. System K is a three-phase three-wire (3φ3W) system that supplies power at 6600V, 22000V, 3300V, etc., at 60Hz or 50Hz, etc., from the power company's substations, etc. However, in the third embodiment of the power plant 20 described later, the pole-mounted transformer K' and subsequent components may be supplied with single-phase two-wire (1φ2W) or 1φ3W (single-phase three-wire) power. Such a system K is first connected to the system panel 21, and the system panel 21 and other related components will be described below.

[0102] <System board 21, etc.> As shown in Figure 13, etc., the grid panel 21 is the part that has the equipment connected to the grid K described above, and this grid panel 21 can be said to be a grid panel 21 such as a power supply panel or an existing panel. The equipment of such a grid panel 21 is built into the panel support (grid panel housing) 21'. The control panel 21 may have any configuration as long as it is connected to the system K and the equipment of the control panel 21 is built into the control panel enclosure 21', but it may also be equipped with at least one of the following: a circuit breaker such as a vacuum circuit breaker (VCB) or a high-voltage circuit breaker (so-called system circuit breaker) 21a, or a surge arrester (SAR) or an instrument transformer (VT, Voltage Transformer, so-called voltage transformer) 21b.

[0103] The circuit breaker 21a in the control panel 21 may be configured to trip via a tripping coil or the like in response to a signal from the control unit 28 (or the current sensor measuring device 1 described above), which will be described later. Such a circuit breaker 21a is installed inside the grid panel 21 (grid panel enclosure 21'), and thus interrupts the electrical circuit between the power generation system 22 (power conditioner 26), which will be described later, and grid K (in other words, the electrical circuit within the grid panel 21, such as the main circuit M from grid K to load F via the grid panel 21).

[0104] Furthermore, as mentioned above, the potential in the main circuit M, etc., may be the same as the potential in the system K (6600V, 22000V, 3300V, etc.), and if the load F described later has a transformer (step-down transformer) F1, the circuit connecting this transformer F1 (the high-voltage side) and the system panel 21 can be said to be part of the main circuit M, etc. The power generation system 22, described later, may be connected to this main power circuit M, etc., via power generation connection equipment 23 (especially branch power circuits 24), which will be described later.

[0105] The instrument transformer 21b in the grid panel 21 is located between the power generation system 22 (power conditioner 26), which will be described later, and grid K, and within the circuitry of the grid panel 21, on the side closer to grid K (closer to grid K) than the aforementioned circuit breaker 21a. The high-voltage side of such an instrument transformer 21b is connected to a circuit closer to system K than the circuit breaker 21a, via a branch circuit (transformed branch circuit) 21d from a branch point (transformed branch point) 21c in that circuit, and the low-voltage side of the instrument transformer 21b is connected to the current sensor measuring device 1, etc.

[0106] The configuration of the instrument transformer 21b in the power distribution panel 21 is not particularly limited, but it may be a configuration that steps down voltages such as 6600V, 22000V, 3300V, etc., to 110V, etc. In the control panel 21, a high-voltage current-limiting fuse (PF, Power Fuse) may be provided in the circuit between the instrument transformer 21b and the transformer branching point 21c.

[0107] <Other equipment in the control panel 21> As shown in Figure 13, the grid panel 21 may also be equipped with at least one of the following: disconnectors (so-called service entrance disconnectors, high-voltage switches) 21e, instrument current transformers (so-called high-voltage grid current transformers) 21f, overcurrent measuring instruments (so-called power receiving OCRs) 21g, and instrument voltage transformers / current transformers (so-called high-voltage voltage / current transformers, which can also be said to constitute part of the trading meter 21h') 21h. Furthermore, the control panel 21 may also be equipped with at least one of the following: an undervoltage relay, an overvoltage relay, an underfrequency relay (also called a frequency reduction relay), an overfrequency relay, a reverse power relay, an energy meter, or a pole-mounted air switch.

[0108] The disconnecting switch (DS) 21e in the grid panel 21 is a device that opens and closes a circuit in the power plant 20 when no current is flowing through it. The disconnecting switch 21e does not have a function to interrupt the current; the current is interrupted by another circuit breaker (such as a grid circuit breaker 21a or a generator circuit breaker 34) before the disconnecting switch is opened or closed. The disconnector 21e can be configured in any way as long as it can open and close the circuit when no current is flowing, but for example, it may be installed in the circuit between the branch point (transformation branch point) 21c to the instrument transformer 21b described above and the power system K.

[0109] The current transformer (CT) 21f in the grid panel 21 is located between the power generation system 22 and grid K, as described later, and within the grid panel 21 (the circuit within the grid panel 21 among the main circuit M, etc.), on the circuit closer to the power generation system 22 than the aforementioned circuit breaker 21a. There are no particular limitations on the configuration of such an instrument current transformer 21f. For example, the current sensor unit 2 of the current sensor measuring device 1 described above may be attached to the output side (secondary side) of the current transformer 21f' circuit 21f', or the current sensor measuring device 1 may be directly connected. The overcurrent relay (OCR) 21g is connected to this instrument current transformer 21f.

[0110] The combined voltage and current transformer (VCT) 21h in the grid panel 21 is a device that combines a voltage transformer (VT) and a current transformer (CT) into one unit, and measures the current and voltage flowing in (or out of) grid panel 21 from grid K. The electricity meter, in combination with the aforementioned combined voltage and current transformer 21h, is a device that measures the amount of electricity flowing in (or out of grid panel 21) from grid K to grid panel 21, and can also be called a meter for trading. The instrument transformer / current transformer 21h can be configured in any way as long as it can measure currents and voltages such as those flowing from system K to the system panel 21. For example, the instrument transformer / current transformer 21h may be installed in the circuit between the disconnector 21e and system K as described above.

[0111] In addition, if an undervoltage relay (which may be the current sensor measuring device 1 mentioned above) is provided in the control panel 21, this undervoltage relay (UVR) is a relay that detects undervoltage and can detect undervoltage U, so any configuration is acceptable, but for example it may be connected to the low-voltage side of the instrument transformer 21b mentioned above. When the undervoltage U detected by the undervoltage relay falls below a predetermined value (6600V, 22000V, 3300V, etc., minus a predetermined voltage (for example, 100V or 200V)), the control unit 28, described later, may trip any circuit breaker (such as the system circuit breaker 21a or the power generation circuit breaker 34) from the power generation system 22 (power conditioner 26) to the grid K. However, this tripping can be said to have a lower priority than the power conditioner 26 conversion stoppage by the relay unit 7 described above. Furthermore, when an undervoltage is detected by an undervoltage relay or the like, and the aforementioned circuit breaker is tripped in hardware (for example, via a tripping coil or the like), the undervoltage relay or the like itself can be said to be the control unit 28 described later.

[0112] If an overvoltage relay is provided in the control panel 21, this overvoltage relay (OVR) is a relay that detects overvoltage, and any configuration is acceptable as long as it can detect overvoltage, but for example, it may be connected to the low-voltage side of the instrument transformer 21b described above. When the overvoltage detected by the overvoltage relay exceeds a predetermined value (such as 6600V, 22000V, or 3300V, plus a predetermined voltage (for example, 100V or 200V)), the control unit 28, described later, may trip any circuit breaker from the power generation system 22 (power conditioner 26) to grid K. However, this tripping also has a lower priority than the power conditioner 26's conversion stoppage by the relay unit 7 described above. Furthermore, when an overvoltage is detected by an overvoltage relay, and the circuit breaker described above is tripped in hardware, the overvoltage relay itself can be said to be the control unit 28 described later.

[0113] If an under-frequency relay is provided in the control panel 21, this under-frequency relay (UFR) is a relay that detects under-frequency, and any configuration is acceptable as long as it can detect under-frequency, but for example, it may be connected to the low-voltage side of the instrument transformer 21b described above. When the underfrequency detected by the underfrequency relay falls below a predetermined value (60Hz or 50Hz, etc., minus a predetermined frequency (for example, 1Hz to 10Hz)), the control unit 28, described later, may trip any of the circuit breakers from the power generation system 22 (power conditioner 26) to grid K. However, this tripping also has a lower priority than the power conditioner 26's conversion stoppage by the relay unit 7 described above. Furthermore, when an underfrequency is detected by an underfrequency relay, and the circuit breaker described above is tripped in hardware, the underfrequency relay itself can be said to be the control unit 28 described later.

[0114] If an overfrequency relay is provided in the control panel 21, this overfrequency relay (OFR) is a relay that detects overfrequency, and any configuration is acceptable as long as it can detect overfrequency, but for example, it may be connected to the low-voltage side of the instrument transformer 21b described above. If the overfrequency detected by the overfrequency relay exceeds a predetermined value (a value obtained by adding a predetermined frequency (for example, 1Hz to 10Hz) from 60Hz or 50Hz, etc.), the control unit 28, described later, may trip one of the circuit breakers from the power generation system 22 to grid K as described above. However, this tripping can be said to have a lower priority than the power conditioner 26 conversion stop by the relay unit 7 described above. Furthermore, when an overfrequency is detected by an overfrequency relay, and the circuit breaker described above is tripped in hardware, the overfrequency relay itself can also be considered a control unit 28, which will be described later.

[0115] If a reverse power relay is provided in the control panel 21, this reverse power (RPR) is a relay that detects reverse power, and any configuration is acceptable as long as it can detect reverse power, but for example, it may be connected to the low-voltage side of the instrument transformer 21b described above. When the reverse power detected by the reverse power relay exceeds a predetermined value (for example, 0.1%, 0.2%, 1.0%, etc. of the power received from system K to the system panel 21 (received power) between 0.1% and 10.0% (0.4%, 1.0%, 5.0%, etc.) or 0.0kW), the control unit 28, described later, may trip one of the circuit breakers from the power generation system 22 to system K as described above. However, this tripping also has a lower priority than the power conditioner 26 conversion stop by the relay unit 7 described above. Furthermore, when a reverse power relay detects reverse power and the circuit breaker described above is tripped in hardware, the reverse power relay itself can also be considered a control unit 28, which will be described later.

[0116] If a power meter is installed in the grid panel 21, the power meter may be configured in any way as long as it can measure the amount of power flowing from grid K to the grid panel 21, for example, it may be connected to an instrument transformer 21h, and the measured values ​​of current and voltage output from the instrument transformer 21h may be input, and the amount of power may be measured by integrating the product of these currents and voltages (the product of voltage and current). Here, the electricity meter can be said to be for purchasing electricity when measuring the amount of electricity flowing from grid K to grid panel 21, and conversely, it can be said to be for selling electricity when measuring the amount of electricity flowing from grid panel 21 to grid K. Furthermore, this electricity meter may be a Class B electrical appliance as defined by the Electrical Appliances and Materials Safety Act.

[0117] If a pole-mounted air switch is installed in the grid panel 21, this pole-mounted air switch (PAS, Pole Air Switches) is used to switch the power plant 20 and the grid K at the demarcation point of responsibility, etc. The pole-mounted air switch can be configured in any way as long as it can open and close the demarcation point between the power plant 20 and the grid K, for example, it may be installed in the circuit between the instrument transformer 21h and the grid K as described above.

[0118] <Control panel support (control panel enclosure) 21' of the control panel 21> As shown in Figure 13, etc., the grid panel enclosure 21', which is the grid panel support, is an enclosure that houses the equipment of the grid panel 21 described above, and it can be said that there is only one of them in a single power plant 20 (or the power generation system 22 described later) for connection to grid K (there is also only one grid panel 21). The system panel enclosure 21' can have any configuration as long as it houses the equipment of the system panel 21, but for example, it may be formed in a roughly rectangular parallelepiped shape overall.

[0119] <Load F etc.> As shown in Figure 13, etc., the load F is a device that consumes power received from the grid K via the grid panel 21, or power generated from the power generation system 22 (power conditioner 26), and the power consumed by such a load F is called the load power (also known as power consumption). The load F can be any configuration as long as it consumes the received or generated power, but for example it could be lighting (lighting load equipment) F in a factory, an industrial motor (IM, Industrial Motor, power load equipment) F in a factory, or a lighting distribution board connected to multiple of the aforementioned lighting Fs.

[0120] Load F may include not only equipment within a factory, but also air conditioners, fluorescent lights, and home appliances in buildings such as houses and office buildings, as well as vehicles such as electric vehicles and gasoline vehicles, and equipment within those vehicles. In addition, the load F may have a transformer (so to speak, a step-down transformer) F1 that transforms (steps down) the power received from the grid K via the grid panel 21 (or the power generated from the power conditioner 26), or a high-voltage AC load break switch (LBS) F2 in the circuit between the transformer F1 and the grid panel 21 (or power conditioner 26), or a molded case circuit breaker (MCCB) F3 in the circuit between the transformer F1 and the industrial motor (or lighting) F mentioned above. Furthermore, the circuit breaker F3 may also have a fuse such as a high-voltage current-limiting fuse.

[0121] There are no particular limitations on the configuration of the transformer F1 in load F. For example, if it is for an industrial motor (power), it may be a three-phase three-wire (3φ3W) configuration that steps down 6600V, 22000V, 3300V, etc. to 440V, 210V, etc. If it is for lighting (lighting), it may be a single-phase three-wire (1φ3W) configuration that steps down 6600V, 22000V, 3300V, etc. to 105V to 210V, etc. Load F does not necessarily have to have such a transformer F1 installed. In this case, another transformer may be installed on the grid panel 21 side, or the output from the power generation system 22 (power conditioner 26) may be directly connected to load F without going through transformer F1.

[0122] The number of loads F may be one or more. The following describes the power generation connection equipment 23 for connecting the power generation system 22, which will be described later, to the load F and grid panel 21 mentioned above.

[0123] <Power generation connection equipment 23 and current sensor measuring device 1> As shown in Figure 13, the power generation connection device 23 is a device that connects the power generation system 22, which will be described later, to the grid panel 21 and load F mentioned above. The current sensor measuring device 1 mentioned above can also be said to be a separate device that connects the power generation system 22 together with the power generation connection device 23, and will therefore be described here. Furthermore, the power generation connection equipment 23 can be configured in any way as long as it connects the power generation system 22 to the grid panel 21 and load F. For example, it may be equipped with a branch circuit 24, and may also be equipped with a power meter (not shown), a power generation circuit breaker 34 (see Figure 16), a power generation transformer 35 (see Figure 16), etc. In addition, these power generation connection equipment 23 may be installed at the same time as the grid panel 21 described above, or they may be retrofitted to an existing grid panel 21 (installed after the grid panel 21 has been installed).

[0124] <Branch circuit 24> As shown in Figure 13, the branch circuit 24 is a circuit that allows the power generation system 22, which will be described later, to be connected to the grid panel 21 and load F described above. For example, its material is something that conducts electricity and includes conductors such as copper, aluminum, silver, gold, and nichrome, as well as cables in which these conductors are covered with an insulator, and general-purpose electric wires. It may also be vinyl-insulated electric wires for electrical equipment. The branch circuit 24 (in other words, the power generation connection device 23) may be connected to the load F via only a miniature circuit breaker (MCCB) 24' without going through the transformer F1 mentioned above, or it may be connected to the main circuit M (in this case, the potential in the branch circuit 24 will be the same high voltage as the potential in the main circuit M or system K (6600V, 22000V, 3300V, etc.)). In other words, one end of the branch circuit 24 may be directly connected to the load F, or to the main circuit M (a circuit at any point between the grid panel 21 and the load F), and the other end of the branch circuit 24 may be connected to the output side of the power generation system 22 (the output side (low voltage side) of the transformer 27). Furthermore, there may be multiple branch circuits 24 in a single power plant 20.

[0125] <Other equipment in power generation connection device 23> The power meter is a power meter for measuring power generation, and may be provided as a power generation connection device 23. Here, "power generation" refers to the power output from the power generation system 22, which will be described later, and can also be called "generated power."

[0126] The power meter can be configured in any way as long as it can measure the power generated. For example, it may be connected to the low-voltage side of the instrument transformer 21b built into the grid panel 21 described above, and also connected to the output side of the power transformer 35, which will be described later and installed in the branch circuit 24. Such a power meter may also have a configuration that includes, for example, an overcurrent relay (OCR, Over Current Relay, so to speak, a power OCR) connected to the power transformer 35 described later, an ammeter connected to this overcurrent relay (so to speak, a power ammeter, which may also be the current sensor measuring device 1 described above), a power meter (which can also be called a power meter in the narrow sense, which may also be the current sensor measuring device 1 described above) connected to the output side of this ammeter and the low-voltage side of the instrument transformer 21b described above, and an output unit that digitizes the measured values ​​from this power meter and outputs them to the control unit 28.

[0127] Based on the value of the generated power measured by the power meter and the received power measured by the current sensor measuring device 1 described above, the output from the power conditioner 26, described later, is controlled by the control unit 28, which will be described later. Furthermore, the output side (high-voltage side) of the transformer 27 in the power generation system 22, which will be described later, will be connected to the branch circuit 24 mentioned above. In this case, the measurement value of the power meter, which is the output from the transformer 27, will be considered to be the power generated from the power generation system 22. Furthermore, if the control unit 28 is located inside a power distribution panel 31 or the like, as described later, the value of the power generation measured by the power meter may be output to the control unit 28 via a wired connection such as a communication cable 1A, or wirelessly.

[0128] The power generation circuit breaker 34 is a circuit breaker such as a high-voltage AC load break switch (LBS) that interrupts the branch circuit 24 (i.e., between the power generation system 22 and system K). The power generation circuit breaker 34 can be configured in any way as long as it interrupts the branch circuit 24. For example, it may be rotatable in the forward and backward directions to improve maintainability, and it may be configured to interrupt the circuit via a capacitor tripping power supply or tripping coil, etc., as described later, based on a signal from the control unit 28 (or current sensor measuring device 1), which will be described later. By interrupting the power generation circuit breaker 34 and the aforementioned system circuit breaker 21a, power generation is stopped from the power generation system 22, or current is stopped from flowing from the grid panel 21 to the system K.

[0129] The power generation connection device 23 may also be equipped with a capacitor tripping power supply and a cable bracket. Furthermore, the power generation connection device 23 may also be equipped with a power shortage relay.

[0130] The capacitor trip device (CTD) in the power generation connection equipment 23 is a device that trips high-voltage AC load switches and vacuum circuit breakers by utilizing the energy generated when the AC input voltage is rectified and discharged into a capacitor. This capacitor trip device then causes the aforementioned power generation circuit breaker 34 to interrupt the branch circuit 24. In this case, the capacitor tripping power supply unit receives a signal from the control unit 28 (or current sensor measuring device 1), which will be described later, and the generator circuit breaker 34 interrupts the branch circuit 24.

[0131] <Power generation system 22> As shown in Figure 13 and other figures, the power generation system 22 according to the present invention is a device that generates power, and its output side is a device that can be connected to the grid panel 21 and load F via the power generation connection equipment 23 and current sensor measuring device 1 described above. The power generation system 22 is not particularly limited in its configuration as long as it generates electricity. For example, it could be a photovoltaic power generation system 22' that generates electricity using solar cells 25' (described later), a power generation system that generates electricity using a motor (generator) rotated by wind, wave (tidal), hydroelectric, thermal, geothermal, etc., or any device capable of generating electricity, such as referring only to solar cells 25'.

[0132] Furthermore, the motors used in wind power generation systems, etc., can be either AC motors or DC motors. The power generation system 22 may also include a power generation unit 25, a power conditioner 26, a transformer 27, and a control unit 28.

[0133] Such a power generation system 22 is connected to the grid panel 21 and load F via power generation connection equipment 23 and current sensor measuring instrument 1. Hereafter, the power generation system 22 will be described primarily as a photovoltaic power generation system 22'.

[0134] <Solar power generation system 22' etc.> As shown in Figure 13, the photovoltaic power generation system 22' may also have a distribution board 31 equipped with a power generation unit 25, a power conditioner 26, a transformer 27, a distribution board support 31', etc., which will be described later. In the solar power generation system 22', the distribution board 31 described above may be connected to a power grid K ending at a transmission tower or utility pole via the power generation connection equipment 23, current sensor measuring device 1, grid panel 21, distribution cables, etc.

[0135] The solar power generation system 22' may have multiple power generation units 25 such as solar cells 25' and multiple distribution boards 31. Furthermore, if there are multiple solar cells 25', the photovoltaic power generation system 22' may have multiple junction boxes (with circuit breakers, etc.) that are electrically connected to a predetermined number of the multiple solar cells 25', and each distribution board 31 will be electrically connected to these multiple junction boxes. However, the functions of these junction boxes may also be built into the distribution board 31, in which case each distribution board 31 will be directly electrically connected to a predetermined number of the multiple solar cells 25'.

[0136] The power generation units 25 such as solar cells 25' and the distribution board 31 are arranged according to the size and shape of the land on which they are installed. For example, the power generation capacity of one distribution board 31 (per power conditioner 26) can be set to, for example, 100kW or more and 180kW or less, 50kW or more and 120kW or less, 30kW or more and 50kW or less (or less than 50kW), and a solar power generation system 22' can be provided with multiple such distribution boards 31. Furthermore, there are no particular limitations on the weight of the distribution panel 31, but for example, it may be between 0.1 tons and 5.0 tons, that is, between 100 kg and 5000 kg, preferably between 150 kg and 2000 kg, and even more preferably between 200 kg and 1000 kg (such as 350 kg).

[0137] <Power generation section 25> As shown in Figure 13, the power generation unit 25 is the part that actually generates electricity. If the power generation system 22 is a photovoltaic power generation system 22', then the solar cell 25' is the power generation unit 25. If the power generation system 22 is a wind power plant or the like, where electricity is generated by a motor rotated by wind power, then the motor is the power generation unit 25.

[0138] <Solar Cell 25'> As shown in Figure 13, the solar cell 25' may be in the form of a panel (flat plate), etc., and when light is shone on it, it generates DC power between the positive electrode (+ electrode) and the negative electrode (- electrode), and the average power generated is between 100W and 400W (for example, 250W). Among these, the positive terminal of one solar cell 25' is connected to the negative terminal of another solar cell 25', and the positive terminal of another solar cell 25' is connected to the negative terminal of yet another solar cell 25', and so on, until multiple solar cells (for example, 5 to 20) are connected in series to form a single solar cell string.

[0139] Thus, the voltage between the positive terminal (power output terminal) and the negative terminal (ground terminal) of a solar cell string consisting of multiple solar cells 25' connected in series is the sum of the DC voltages generated by each solar cell 25'. This voltage fluctuates due to weather, time of day, degradation or failure of each solar cell 25', and misalignment of their installation positions, but it is between 200V and 1500V. Furthermore, the power output from the power output terminal of the solar cell string is the sum of the power of each solar cell 25', and is between 500W and 6000W (for example, if 14 solar cells 25' with an output power of 250W each are connected, the total power is 3500W = 3.5kW).

[0140] In this case, connecting the solar cells 25' in series means that if even one of the solar cells 25' malfunctions, the current in that solar cell 25' will be interrupted, making it difficult to output the power generated by the other solar cells 25'. Therefore, by providing a bypass diode (not shown) for each series-connected solar cell 25', the current is configured to bypass (redirect) the malfunctioning solar cell 25'.

[0141] Furthermore, this bypass diode is connected in parallel to the solar cell 25' in the direction that current flows from its negative terminal to its positive terminal. Specifically, the cathode of the bypass diode is connected to the positive terminal of the solar cell 25', and the anode of the bypass diode is connected to the negative terminal of the solar cell 25'. Such solar cells 25' may be installed on the mounting surface via a frame.

[0142] The installation surface for the solar cell 25' (or mounting frame) is the installation surface on which the solar power generation system 22' itself is installed. Any surface is acceptable as long as the solar cell 25' can be installed on it, such as former golf course land, mountainous land, vacant lot, fallow land, farmland, etc., as well as the roof or rooftop of a building, or a wall. Furthermore, the mounting surface of the solar cell 25' may be the same as the mounting surface of the grid panel 21 or the load F, or it may be a different mounting surface from the grid panel 21 or the load F. Furthermore, the mounting structure may be tilted to support the solar cells 25' in a predetermined direction (for example, so that they become lower as they face south) in order to increase the power generation of the solar power generation system 22'. The angle can be any degree as long as sufficient power generation can be obtained, such as 10 degrees or 5 degrees.

[0143] <Power Conditioner 26> As shown in Figure 13, the power conditioner 26 is a device that converts DC current from external sources such as the aforementioned solar cells 25', or AC current from AC motors of wind power generation systems, into AC power that matches the voltage and phase of the grid K, and outputs it. The power conditioner 26 may include an inverter device that converts direct current from a solar cell 25' or the like into alternating current (for example, 100V to 440V), a control unit that controls the voltage and frequency of the alternating current converted by the inverter device, and an air circuit breaker (ACB).

[0144] The power conditioner 26 may have a rotating fan-like air blowing mechanism to release the air inside its casing, which houses the inverter device, control unit, circuit breaker, etc. Furthermore, such a power conditioner 26 is also sometimes referred to as a power conditioner 26 for short.

[0145] The power conditioner 26 is controlled by a signal from the control unit 28, described later, to limit (suppress) the power output from the power conditioner 26 to a predetermined value (such as a target upper limit). (In other words, it may also be configured so that the conversion in the power conditioner 26 is stopped by a signal from the current sensor measuring device 1, etc. (By stopping the conversion in this way, it can be said that no power is output from the power conditioner 26.) Furthermore, as mentioned above, the number of power conditioners 26 may be one or more. If there are multiple power conditioners 26, when stopping the conversion of the power conditioners 26 based on a signal from the current sensor measuring device 1, etc., the conversion of all power conditioners 26 may be stopped at once, or the conversion of at least some of the power conditioners 26 may be stopped first.

[0146] The power conditioner 26 is housed in a separate enclosure (power conditioner enclosure) from the distribution board 31 which has the transformer 27, etc., described later. If the power conditioner 26 is installed on the distribution board support 31' of the distribution board 31 or housed in the power conditioner enclosure, then multiple power conditioner enclosures (i.e., power conditioners 26) may be distributed and installed in a single solar power generation system 22' (below the solar cells 25', for example).

[0147] <Transformer 27> As shown in Figure 13, etc., the transformer 27 is a transformer (so to speak, a step-down transformer) that transforms (steps down) the AC current from the one or more power conditioners 26 described above into a lower voltage AC current. The transformer 27 can be configured in any way as long as it transforms the AC current in the distribution panel 31 (described later) into a lower voltage AC current. For example, it may be a dry type, covered by a transformer housing, and mounted on the distribution panel support 31'.

[0148] Furthermore, the transformer 27 can also be said to be located in the branch circuit 24 (the circuit between the load F and the power conditioner 26, or the circuit between the main circuit M, etc., and the power conditioner 26) as part of the power plant 20 as a whole. The output from transformer 27 (i.e., the generated power) may be directly connected to load F via a molded case circuit breaker (MCCB). The transformer 27 may have holes in the lower side of the transformer housing for routing cables from the power conditioner 26, etc. The lower front and rear of the transformer housing are open, and cooling air may be drawn in through these openings, and warm air may be released through the gap between the transformer housing and its top cover. The transformer 27 may also convert an alternating current (e.g., 100V to 440V) from outside the distribution panel 31 to a lower voltage alternating current (e.g., 200V) that is suitable for consumption by the load F.

[0149] The transformer 27 may have sufficient capacity while being at a lower height depending on how the iron core (magnetic core) is assembled. There are no particular restrictions on the specific height of such a transformer 27, but for example it may be 1500 mm or less (900 mm to 1500 mm), preferably 1400 mm or less (900 mm to 1400 mm), more preferably 1200 mm or less (95 mm to 1200 mm), and more preferably 1150 mm or less (950 mm to 1150 mm, 1100 mm, etc.). There are no particular restrictions on the capacity of the transformer 27, but for example, it may be 1 kVA or more and 500 kVA or less, preferably 10 kVA or more and 200 kVA or less, and even more preferably 20 kVA or more and 100 kVA or less.

[0150] Such a transformer 27 may, for example, be configured to step down a voltage of 100V to 440V, etc., to 200V, etc., using a three-phase three-wire (3φ3W) system. As mentioned above, the number of transformers 27 may be one or more. Multiple transformers 27 may be distributed within a single solar power generation system 22' (e.g., below the solar cells 25'). The control unit 28 that controls the power conditioner 26 and / or grid panel 21 in the power generation system 22 described above will be described below.

[0151] <Control Unit 28> As shown in Figure 13, the control unit 28 is the part that controls the power conditioner 26 and / or the system panel 21 described above. The control unit 28 may be, for example, a smart logger installed inside the cabinet 32 ​​in the case of the distribution panel 31 described later, or it may be a sequencer or the like. The control unit 28 may control the power generated from the power generation system 22 (which can also be called the output of the power conditioner 26) by considering the sum of the power received from the system K to the grid panel 21 and the power generated from the power generation system 22 as the power consumption of the load F. Furthermore, when the control unit 28 controls the output of the power conditioner 26 (gives the power conditioner 26 an output target value), it may give the power conditioner 26 an output target value that is slightly higher than the actual power generation target value (power on the high-voltage side (output side) of the transformer 27 equipped with a power meter), taking into account power losses such as the transformation loss (which can also be called a step-up loss) in the transformer 27 mentioned above. Furthermore, the time interval at which the control unit 28 provides the power conditioner 26 with an output target value (target assignment interval) may be set at predetermined time intervals (predetermined target assignment interval), but it may also be less than 0.1 seconds or as short as 0.05 seconds, such as every 0.1 seconds, every 0.25 seconds, every 1 second, or every 5 seconds (here, the target assignment interval may be longer than or the same length as the sampling time, which will be described later).

[0152] Furthermore, if the current value detected by the current sensor measuring device 1 exceeds a predetermined threshold, the control unit 28 may stop the conversion of the power conditioner 26 or trip any of the circuit breakers (such as the generator circuit breaker 34 or the system circuit breaker 21a) in the circuit from the power conditioner 26 to the system K. Furthermore, if the conversion of the power conditioner 26 is stopped, there is no need to adjust the output from the power conditioner 26 to match the voltage and phase of grid K when restarting the conversion. Therefore, compared to the case where any part of the circuit from the power conditioner 26 to grid K is interrupted, the power plant 20 can be restored in a shorter time and with less effort (shorter and easier system restoration).

[0153] In addition, it can be said that the current sensor measuring device 1 is included in the control unit 28. The control unit 28 may be located anywhere within the power plant 20, but for example, it may be located in the switchboard 31, which will be described later. The following describes the control unit 28, the power conditioner 26 and transformer 27 mentioned above, the distribution board support 31', and the distribution board 31 equipped with the current sensor measuring device 1 mentioned above.

[0154] <Switchboard 31, switchboard support 31'> As shown in Figure 13, etc., the distribution board 31, which is one type of panel according to the present invention, can be said to be a panel having a distribution board support (which can also be called a distribution board housing or distribution board frame) 31', the power conditioner 26 described above, the transformer 27 described above, the control unit 28 described above, and the current sensor measuring device 1 described above. In the distribution panel 31, a power conditioner 26 built into a power conditioner enclosure and a transformer 27 covered by a transformer enclosure are mounted on the distribution panel support 31', and a current sensor measuring device 1 and a control unit 28 etc. are provided built into the cabinet 32, and a power generation meter may also be provided inside the cabinet 32.

[0155] The distribution panel 31 may have multiple current sensor measuring devices 1 as described above installed inside the cabinet 32, as well as other equipment such as a ground fault overvoltage relay (OVGR) 33, a circuit breaker (MCCB, which can also be called a generator circuit breaker 34), communication equipment (such as a router), an uninterruptible power supply (UPS), and outlets. Furthermore, the ground fault overvoltage relay 33 may be connected to the main circuit M, etc., within the grid panel 21 via a zero-phase potential device (ZPD) 21z. Furthermore, the number of distribution boards 31 (i.e., distribution board supports 31') in one solar power generation system 22' may be one or more, as described above, but it may also be the same number as the number of power conditioners 26 and transformers 27, etc. Multiple distribution panels 31 may be distributed within a single solar power generation system 22' (e.g., below the solar cells 25').

[0156] <Power plant 20 of the second embodiment> Figure 14 shows a power plant 20 according to a second embodiment of the present invention. The most significant difference between this second embodiment and the first embodiment is that it is an LBS-receiving type that receives high voltage power with a capacity of 300 kVA or less (a type that has a high-voltage AC load switch (LBS) 21a' instead of a high-voltage circuit breaker (VCB) 21a, and does not have a disconnector 21e, an instrument current transformer 21f, a high-voltage AC load switch F2, etc.).

[0157] Furthermore, in the second embodiment as well, the current sensor unit 2 of the current sensor measuring device 1 is directly attached to the main circuit M from the system K to the load F (in particular, the circuit between the instrument transformer 21h and the system K within the system panel 21). The configuration, effects, and usage of other components such as the power plant 20, current sensor measuring instrument 1, switchboard 31, power generation system 22, power generation connection equipment 23, power generation unit 25, power conditioner 26, transformer 27, and control unit 28 are the same as in the first embodiment.

[0158] <Power plant 20 of the third embodiment> Figure 15 shows a power plant 20 according to a third embodiment of the present invention. The most significant difference between this third embodiment and the first and second embodiments is that it is a low-voltage power receiving type with a capacity of less than 50kW (a type that has a wiring circuit breaker (MCCB) 21a'' and a trading meter 21h' instead of a high-voltage circuit breaker (VCB) 21a, a high-voltage AC load switch (LBS) 21a', and an instrument transformer / current transformer 21h, while simultaneously lacking a zero-phase detector 21z, a ground fault overvoltage relay 33, a step-down transformer F1, etc.).

[0159] Furthermore, the third embodiment differs from the first and second embodiments in that it has a pole-mounted transformer (step-down transformer) K' in the circuit between the instrument transformer 21h and the power system K, and at the same time, the current sensor unit 2 of the current sensor measuring device 1 is installed in the circuit between the instrument transformer 21h and the circuit breaker (MCCB) 21a''. The configuration, effects, and usage of other components such as the power plant 20, current sensor measuring instrument 1, switchboard 31, power generation system 22, power generation connection equipment 23, power generation unit 25, power conditioner 26, transformer 27, and control unit 28 are the same as those in the first and second embodiments.

[0160] <Power plant 20 of the fourth embodiment> Figure 16 shows a power plant 20 according to a fourth embodiment of the present invention. The most significant difference between this fourth embodiment and the first to third embodiments is that, instead of the distribution board 31, the power generation connection board 41 is connected to the grid board 21 (in other words, it is retrofitted to the grid board 21).

[0161] <Power generation connection panel 41, power generation connection panel support 41'> As shown in Figure 8, the power generation connection panel 41 incorporates the aforementioned power generation connection equipment 23 and current sensor measuring instrument 1 into its power generation connection panel support 41' (power generation connection panel housing 41'). It can be said that the power generation connection panel 41 consolidates the equipment necessary for connecting the power generation system 22 to the existing grid panel 21 and load F, enabling the user of the power plant 20 to consume the electricity generated by the power generation system 22 at the load F ("self-consumption"). The power generation connection panel 41 can have any configuration as long as it connects the power generation system 22 to the existing grid panel 21 and load F and the power generation connection equipment 23 is built into the power generation connection panel housing 41'. For example, it may also be equipped with branch circuits 24, current sensor measuring instrument 1, instrument transformer (VT), high-voltage AC load switch (LBS) 34, power generation transformer 35, etc.

[0162] Furthermore, this high-voltage AC load switch (LBS) 34 can also be described as a power generation circuit breaker 34. Furthermore, one power generation connection panel 41 (power generation connection panel housing 41') may incorporate two current sensor measuring devices 1. In this case, one current sensor measuring device 1 (current sensor measuring device 1a for reverse power, etc.) detects the aforementioned reverse power, etc., and performs a relay operation according to this reverse power, while the other current sensor measuring device 1 (current sensor measuring device 1b for power generation) may detect power generation as a power generation meter. Furthermore, in the fourth embodiment, the current sensor unit 2 of the current sensor measuring device 1 for reverse power, etc., may be directly attached to the main circuit M from system K to load F (in particular, the circuit between the instrument transformer 21h and system K within the system panel 21), or it may be attached to the output side (secondary side) circuit 21f' of the instrument transformer 21f within the system panel 21 (see the dotted line in Figure 16). Furthermore, the current sensor unit 2 of the other current sensor measuring device 1 is attached to the branch circuit 24.

[0163] Furthermore, in the fourth embodiment of the power plant 20, there are one or more distribution panels 31 in which the equipment is built into a distribution panel housing 31' so that the equipment is not exposed. These distribution panels 31 house transformers (step-up transformers), power transmission units, power collection units, etc., and one or more power conditioners 26 connect multiple power generation units 25 (solar cells 25') to each distribution panel 31. Furthermore, the control unit 28 may be a PLC (Programmable Logic Controller). The configuration, effects, and usage of other power plants 20, current sensor measuring devices 1, etc., are the same as in the first to third embodiments.

[0164] <Other> The present invention is not limited to the embodiments described above. The current sensor measuring device 1, the panel, the power plant 20, and other components, as well as the overall structure, shape, dimensions, etc., can be modified as appropriate in accordance with the spirit of the present invention. The current sensor measuring device 1 does not necessarily have to have a relay unit 7. Although the current sensor measuring device 1 was described above as being installed inside the grid panel 21 or inside the power generation connection panel 41, it may also be installed anywhere in the power plant 20, such as inside the switchboard 31. The current sensor measuring device 1 does not necessarily have to have the output unit described above.

[0165] As mentioned above, the rated current range for the current sensor measuring device 1 is 15A or more and 1800A or less. However, it can also be said that the minimum value within this rated range should be 1 / 50 to 1 / 150 of the maximum value within this rated range (e.g., 1 / 50, 1 / 60, 1 / 90, 1 / 120, 1 / 150, etc.). For example, as shown in Figure 11, the rated range could be 0.750A or more and 50.000A or 1.000A or less. The rated range may be 50,000A or less, 2,000A or more and 180,000A or less, 1,500A or more and 180,000A or less, or other ranges such as 0,100A or more and 5,000A or less, 0,200A or more and 18,000A or less, 0,150A or more and 18,000A or less, 0,010A or more and 0,500A or less, 0,020A or more and 1,800A or less, 0,015A or more and 1,800A or less, etc. The current sensor measuring device 1 (current sensor unit 2) can be installed not only in the main circuit M, branch circuits 24, and the circuit 21f' on the secondary side of the instrument current transformer 21f (output from the instrument current transformer 21f) as described above, but also in the grid panel 21, power generation connection panel 41, switchboard 31, power generation system 22 such as the solar power generation system 22', and in any of the circuits within the power plant 20. The current sensor measuring device 1 may be installed not only in system panels 21 such as power supply panels, but also in extra-high voltage panels (extra-high voltage equipment), high voltage panels (high voltage equipment), low voltage panels (low voltage equipment), monitoring panels (monitoring equipment), control panels (control equipment), substations (substation equipment), equipment for buildings and condominiums, power receiving panels (especially existing power receiving panels), and lighting distribution panels. These panels can also be said to be panels according to the present invention, having a panel support (panel housing or panel frame) on which the current sensor measuring device 1 is installed.

[0166] The roughly rectangular coil 4 in the current sensor unit 2 does not have to be of the switching type, but it may or may not be of the switching type. Furthermore, if the roughly rectangular coil 4 is of the open / close type, it can be attached to the predetermined electrical circuit S described above without cleaving the predetermined electrical circuit S, and can be easily retrofitted by opening and closing itself without cleaving the predetermined electrical circuit S that is the target of detection. The current sensor unit 2 may have potting applied between the roughly rectangular coil 4 and the sensor housing 10, and the resin used for this process may be polyurethane resin or the like. This potting process makes it difficult for dust and dirt to adhere to the roughly rectangular coil 4, providing waterproofing and moisture resistance. Furthermore, because the inside of the sensor housing 10 is filled with resin and secured, the roughly rectangular coil 4 can be said to be more resistant to vibration and shock. The surface of the core member 5 may have a coating (film) formed on it for rust prevention, insulation, etc. The length of the sensor circuit 11 is not particularly limited, but for example, it may be 100 cm or more and 500 cm or less, preferably 200 cm or more and 400 cm or less, and even more preferably 250 cm or more and 350 cm or less (such as 300 cm, 280 cm, or 320 cm). The power plant 20 may have storage batteries, fuel cells, generators that run on fuels such as gasoline, etc. The reverse power relay may be installed anywhere in the power plant 20, such as inside the grid panel 21 as described above, or inside the switchboard 31 or the power generation connection panel 41. [Industrial applicability]

[0167] The current sensor measuring instrument and panel of the present invention can be used in solar power generation systems, etc., regardless of the amount or scale of power generation. In addition to solar power generation systems, it can be used as an ammeter, etc., in systems that generate electricity using generators (AC motors, etc.) rotated by wind, hydro, wave, geothermal, etc., regardless of the magnitude of the current value in the circuit to be measured. Furthermore, it can be used in system panels such as power purchase panels, as well as extra-high voltage panels (extra-high voltage equipment), high voltage panels (high voltage equipment), low voltage panels (low voltage equipment), monitoring panels (monitoring equipment), control panels (control equipment), substations (substation equipment), equipment for buildings and condominiums, power receiving panels, lighting distribution panels, and all other power plants that do not generate electricity, and can be used both indoors and outdoors. The power plant of the present invention can be used for solar power generation systems and the like, regardless of their power generation capacity or scale. In addition to solar power generation systems, it can be used in plants that generate electricity using generators (such as AC motors) rotated by wind, hydroelectric, wave, or geothermal power, and can be used both outdoors and indoors. [Explanation of Symbols]

[0168] 1. Current sensor measuring device 2 Current sensor section 3. Measurement Unit 4. Roughly rectangular coil 5 Core members 6. Correction Unit 7 Relay section 8 cabinets 20 Power Plants 21 System board 22 Power generation systems K lineage F load

Claims

1. A current sensor measuring device that can be attached to a predetermined electrical circuit and used, The system includes a current sensor unit (2) that outputs a current corresponding to the current in the predetermined circuit, and a measuring unit (3) that measures at least the value of the current in the predetermined circuit based on the current output from the current sensor unit (2). The current sensor unit (2) includes a substantially rectangular coil (4), The aforementioned roughly rectangular coil (4) is formed by butting the end faces of two roughly U-shaped core members (5) together. The two roughly U-shaped core members (5) are, as a whole, roughly rectangular in shape. A winding is wound around each of the two roughly rectangular, roughly U-shaped core members (5) via a coil bobbin (5A). The current sensor unit (2) comprises a sensor housing (10) that houses the substantially rectangular coil (4) and has an opening in the approximate center. The two roughly rectangular, roughly U-shaped core members (5) are roughly rectangular in shape when viewed from above, while the shape of the opening in the sensor housing (10) is roughly square in shape when viewed from above. The rated current range for this current sensor measuring device is 15A or more and 1800A or less. The current sensor measuring device is, In a power plant having a grid (K) to which a grid panel (21) is connected, a load (F) and / or a power generation system (22) is connected to the grid panel (21), a main circuit (M) from the grid (K) to the load (F) via the grid panel (21), an instrument current transformer (21f) provided in the grid panel (21), and an output circuit (21f') of the instrument current transformer (21f), A current sensor measuring device characterized by being usable by being attached to either the main circuit (M) or the output circuit (21f') of the current transformer (21f).

2. A current sensor measuring device that can be attached to a predetermined electrical circuit and used, The system includes a current sensor unit (2) that outputs a current corresponding to the current in the predetermined circuit, and a measuring unit (3) that measures at least the value of the current in the predetermined circuit based on the current output from the current sensor unit (2). The current sensor unit (2) includes a substantially rectangular coil (4), The aforementioned roughly rectangular coil (4) is formed by butting the end faces of two roughly U-shaped core members (5) together. The two roughly U-shaped core members (5) are, as a whole, roughly rectangular in shape. A winding is wound around each of the two roughly rectangular, roughly U-shaped core members (5) and their opposing sides. The number of windings wrapped around each of the two opposing pairs of edges is one. The number of turns of each winding wound around each of the two opposing sides is the same. The two roughly rectangular, roughly U-shaped core members (5) have a uniform thickness. Each of the aforementioned roughly U-shaped core members (5) comprises a body portion (5a) and branch portions (5b) provided at each end of the body portion (5a), In each of the aforementioned roughly U-shaped core members (5), the length of the body portion (5a) is approximately the same, and the length of each of the branch portions (5b) is approximately the same. The rated current range for this current sensor measuring device is 15A or more and 1800A or less. The current sensor measuring device is, In a power plant having a grid (K) to which a grid panel (21) is connected, a load (F) and / or a power generation system (22) is connected to the grid panel (21), a main circuit (M) from the grid (K) to the load (F) via the grid panel (21), an instrument current transformer (21f) provided in the grid panel (21), and an output circuit (21f') of the instrument current transformer (21f), A current sensor measuring device characterized by being usable by being attached to either the main circuit (M) or the output circuit (21f') of the current transformer (21f).

3. The main circuit (M) and the output circuit (21f') of the current transformer (21f) are three-phase three-wire, The current sensor measuring device according to claim 1 or 2, characterized in that the current sensor measuring device can be attached to and used in the shielded portion where the electric field in two of the three wires of the main circuit (M) and the output circuit (21f') of the instrument current transformer (21f) is shielded.

4. The current sensor measuring device according to claim 1 or 2, characterized in that the potential of the main circuit (M) is the same as that of the system (K), and the potential of the output circuit (21f') of the instrument current transformer (21f) is one of 110V, 220V, and 440V.

5. The system also includes a relay unit (7) that performs a relay operation according to the value in the predetermined circuit measured by the measurement unit (3), The current sensor measuring device according to claim 1 or 2, characterized in that the measuring unit (3) and the relay unit (7) are housed in the same housing (8).

6. A power plant comprising a grid panel (21) connected to a grid (K), a load (F) and / or a power generation system (22) connected to the grid panel (21), a current sensor measuring instrument (1) attached to a predetermined circuit, a main circuit (M) from the grid (K) to the load (F) via the grid panel (21), a current transformer (21f) provided on the grid panel (21), and a circuit (21f') on the output side of the current transformer (21f), The current sensor measuring device (1) includes a current sensor unit (2) that outputs a current corresponding to the current in the predetermined circuit, and a measuring unit (3) that measures at least the current in the circuit based on the current output from the current sensor unit (2). The current sensor unit (2) includes a substantially rectangular coil (4), The aforementioned roughly rectangular coil (4) is formed by butting the end faces of two roughly U-shaped core members (5) together. The two roughly U-shaped core members (5) are, as a whole, roughly rectangular in shape. A winding is wound around each of the two roughly rectangular, roughly U-shaped core members (5) via a coil bobbin (5A). The current sensor unit (2) comprises a sensor housing (10) that houses the substantially rectangular coil (4) and has an opening in the approximate center. The two roughly rectangular, roughly U-shaped core members (5) are roughly rectangular in shape when viewed from above, while the shape of the opening in the sensor housing (10) is roughly square in shape when viewed from above. The rated current range of the current sensor measuring device (1) is 15A or more and 1800A or less. The current sensor measuring device (1) is A power plant characterized in that it is attached to both the main circuit (M) and the output circuit (21f') of the instrument current transformer (21f).

7. A power plant comprising a grid panel (21) connected to a grid (K), a load (F) and / or a power generation system (22) connected to the grid panel (21), a current sensor measuring instrument (1) attached to a predetermined circuit, a main circuit (M) from the grid (K) to the load (F) via the grid panel (21), a current transformer (21f) provided on the grid panel (21), and a circuit (21f') on the output side of the current transformer (21f), The current sensor measuring device (1) includes a current sensor unit (2) that outputs a current corresponding to the current in the predetermined circuit, and a measuring unit (3) that measures at least the current in the circuit based on the current output from the current sensor unit (2). The current sensor unit (2) includes a substantially rectangular coil (4), The aforementioned roughly rectangular coil (4) is formed by butting the end faces of two roughly U-shaped core members (5) together. The two roughly U-shaped core members (5) are, as a whole, roughly rectangular in shape. A winding is wound around each of the two roughly rectangular, roughly U-shaped core members (5) and their opposing sides. The number of windings wrapped around each of the two opposing pairs of edges is one. The number of turns of each winding wound around each of the two opposing sides is the same. The two roughly rectangular, roughly U-shaped core members (5) have a uniform thickness. Each of the aforementioned roughly U-shaped core members (5) comprises a body portion (5a) and branch portions (5b) provided at each end of the body portion (5a), In each of the aforementioned roughly U-shaped core members (5), the length of the body portion (5a) is approximately the same, and the length of each of the branch portions (5b) is approximately the same. The rated current range of the current sensor measuring device (1) is 15A or more and 1800A or less. The current sensor measuring device (1) is A power plant characterized in that it is attached to both the main circuit (M) and the output circuit (21f') of the instrument current transformer (21f).

Images