JP2015212632A - Power transmission direction detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect a direction in which power is transmitted through a detection electric path in a non-contact state, without calculating effective power.SOLUTION: A power transmission direction detector comprises: a voltage detection part 4 for detecting a voltage waveform of an AC voltage of a detection electric path 50, in a non-contact state, and for outputting a voltage signal Vv; and a current detection part 5 for detecting an AC current, in a non-contact state, flowing through the detection electric path 50, and for outputting a voltage signal Vi indicating a waveform of the current in a state where a phase when the AC current flows through the detection electric path 50 in a second direction B is opposite to a phase when the AC current flows through the detection electric path 50 in a first direction A opposite to the second direction B. The current detection part 5 also outputs the voltage signal Vi, in a case of the first direction A, in a state where a phase difference from the voltage signal Vv ranges from -90° to +90°. In addition, the power transmission direction detector includes: binarization parts 6, 7 for outputting binarized signals S1, S2 of the voltage signals Vv, Vi; and a processing part 8 for deciding, when a duty ratio of a logical AND of the binarized signals S1, S2 is 0.25 or more, that power is transmitted in the first direction A, and, when the duty ratio is less than 0.25, that the power is transmitted in the second direction B, and for displaying the power transmission direction on a display part 9.

Description

  The present invention relates to a power transmission direction detection device that detects a power transmission direction (power flow direction) in a detection electric circuit.

  As this type of power transmission direction detection device, the present applicant has already proposed a power measuring instrument disclosed in Patent Document 1 below. This power measuring device is a power measuring device that detects the voltage and current of the measurement circuit (measured circuit) and calculates the effective power generated in the measurement circuit based on the detected voltage and current. Based on the polarity of electric power, it is comprised so that measurement of the power transmission direction (power flow direction) in a measurement electric circuit is possible, and it functions also as a power transmission direction detection apparatus. Specifically, when this power measuring device functions as a power transmission direction detection device, when the polarity of the active power is positive (+), power is transmitted from the power supply side to the load on the measurement circuit ( When the power flow direction is “consumption” and the polarity of the active power is negative (−), power is transmitted from the load to the power supply side on the measurement circuit (the power flow direction is "Regeneration").

Japanese Patent Laid-Open No. 11-64403 (2nd page, FIG. 4)

  However, this power transmission direction detection device (power measuring device) has the following problems to be improved. That is, for example, when renovating an indoor wiring, the worker of the construction may want to know the power transmission direction (the power flow direction) using the desired wiring as a detection power circuit. However, in the conventional power transmission direction detection device described above, when detecting the power transmission direction, it is necessary to detect the current and voltage of the detection circuit, and to calculate the active power based on the detected current and voltage. For this reason, the power transmission direction detection device has a problem to be improved that the processing is complicated because the processing for calculating the active power is required, and as a result, the device cost increases.

  In order to improve this problem, it is necessary to carry out the work of electrically connecting the power transmission direction detection device to the core wire (conductive wire) constituting the detection electric circuit for the detection of the current and voltage of the detection electric circuit. Since it is troublesome for the operator, it is preferable to omit the connection work of the power transmission direction detection device to the core wire of the detection electric circuit. In this case, a technique for detecting the current and voltage of the detection circuit in a non-contact manner is known, and there are various methods (for example, Japanese Patent Laid-Open No. 2012-137496 already proposed by the applicant of the present application). Disclosure technology), any one of these can be used.

  The present invention has been made in view of such a problem, and it is a main object of the present invention to provide a power transmission direction detection device that can detect the power transmission direction of a detection electric circuit in a non-contact manner without executing processing for calculating active power. And

  In order to achieve the above object, a power transmission direction detection device according to claim 1 is configured to detect a voltage waveform of an alternating voltage applied to a detection electric circuit in a non-contact manner and output the detected voltage waveform, and to apply the alternating voltage. The current waveform of the alternating current flowing through the detection circuit is detected in a non-contact manner, and the detected current waveform is detected with respect to the phase when the alternating current flows through the detection circuit in the first direction. And a current detection unit that outputs in a state in which the phase when flowing in the second direction opposite to the direction of is opposite to the direction of the detection, and the detection electric circuit based on the detected voltage waveform and the current waveform In the power transmission direction detecting device for detecting a power transmission direction in the above, the current detection unit, when the alternating current is flowing in the first direction, has a phase of the voltage waveform minus 90 ° or more plus 90 °. Less than A first binarization unit that outputs the current waveform in a phase difference state within the range of the above, binarizes the voltage waveform with reference to zero volts, and outputs a first binarized signal; And a second binarization unit that binarizes and outputs a second binarized signal, and a duty ratio for a logical product of the first binarized signal and the second binarized signal is 0.25 The processing unit detects that the power transmission direction is the first direction at the above time, and detects that the power transmission direction is the second direction when the duty ratio is less than 0.25. A first output unit that outputs information of the detected power transmission direction.

  The power transmission direction detection device according to claim 2, wherein the processing unit is configured to change the alternating current when the logic is low based on the logic of the second binarized signal when the first binarized signal rises. When the phase of the alternating current is delayed with respect to the phase of the voltage and the logic is High, it is detected that the phase of the alternating current is advanced with respect to the phase of the alternating voltage, and the processing unit And a second output unit that outputs information on the state of the phase of the alternating current with respect to the phase of the alternating voltage detected in step (b).

  According to the power transmission direction detection device according to claim 1, the voltage detection unit, the current detection unit, the first binarization unit, the second binarization unit, the processing unit, and the first output unit are provided. Without executing the process of calculating the active power transmitted in step 1, the power transmission direction of the detected electric circuit can be detected in a non-contact manner, and the information on the power transmission direction can be output to the first output unit. Therefore, the worker can surely recognize the power transmission direction of the detection electric circuit based on the information output from the first output unit.

  According to the power transmission direction detection device according to claim 2, the AC voltage is determined based on the information output from the second output unit by clamping to the detection electric circuit so that the detected power transmission direction coincides with the first direction. The phase state of the alternating current with respect to the phase of the current (whether the phase of the alternating current is advanced or delayed with respect to the phase of the alternating voltage) can be detected without contact.

1 is a configuration diagram illustrating a configuration of a power transmission direction detection device 1. FIG. It is explanatory drawing for demonstrating the structure of the process part 8 and the display part 9 of the power transmission direction detection apparatus 1. FIG. It is a perspective view in the use condition of power transmission direction detection apparatus. 4 is a waveform diagram for explaining the operation of the power transmission direction detection device 1. FIG. It is another waveform diagram for demonstrating operation | movement of the power transmission direction detection apparatus.

  Hereinafter, embodiments of a power transmission direction detection device will be described with reference to the accompanying drawings.

  Initially, the structure of the power transmission direction detection apparatus 1 shown in FIG. 1 as an example of a power transmission direction detection apparatus is demonstrated. The power transmission direction detection device 1 includes a clamp unit 2, a sensor body unit 3, a voltage detection unit 4, a current detection unit 5, a first binarization unit 6, a second binarization unit 7, a processing unit 8, and an output unit (described later). In this example, the display unit 9 is provided as an example, and is configured to detect the power transmission direction in the detection circuit 50. In this example, as shown in FIGS. 1 and 2, the detection electric circuit 50 includes a core wire 50 a made of a conductor and an insulating coating 50 b that covers the outer periphery of the core wire 50 a. May be constituted only by the core wire 50a.

  The clamp portion 2 is U-shaped using a synthetic resin material (material having electrical insulation), or a pair of arc shapes in which the other end portions are connected to each other so that one end portions can be brought into contact with and separated from each other (in this example, As an example, a clamp arm 11 formed in a U shape as shown in FIGS. 1 and 3 is provided, and the detection electric circuit 50 can be clamped by this clamp arm 11 (the detection electric circuit 50 can be introduced between the clamp arms 11). It is configured.

  In the clamp arm 11, a later-described detection electrode 4a constituting a part of the voltage detection unit 4 is disposed, and a later-described magnetoelectric conversion element 5a and a magnetic core 5b constituting a part of the current detection unit 5 are disposed. Is arranged.

  The sensor body 3 is a long cylindrical body made of a synthetic resin material (for example, a polygonal cylindrical body or a cylindrical body having a thickness that can be grasped with one hand and closed at both ends. In this example, as an example 1 to 3, and a clamp portion 2 is disposed at one end portion in the length direction. In addition, a voltage detection unit 4, a current detection unit 5, a first binarization unit 6, a second binarization unit 7, a processing unit 8, and a display unit 9 are disposed inside the sensor body 3. .

  The voltage detection unit 4 detects and outputs the voltage waveform of the AC voltage V1 applied to the detection electric circuit 50 in a non-contact manner. As an example, the voltage detection unit 4 is configured in the same manner as the voltage detection circuit disclosed in the above-described Japanese Patent Application Laid-Open No. 2012-137497, and is detected by capacitive coupling with the detection circuit 50 (in this example, the core wire 50a of the detection circuit 50). Reference with the same voltage and phase as the AC voltage V1 applied to the detection electric circuit 50 (in this example, the core wire 50a of the detection electric circuit 50) based on the current flowing between the electrode 4a and the detection electric circuit 50 and the detection electrode 4a And a voltage detection circuit 4b for generating a potential signal. In this case, the detection electrode 4 a is disposed in the clamp arm 11. Further, the voltage detection circuit 4b has the same voltage as that of the reference potential signal (that is, the same phase as the AC voltage V1) and a voltage that has been stepped down to a voltage that can be processed by a subsequent component (first binarization unit 6). The signal Vv is also simultaneously generated and output as a signal (AC signal) indicating the voltage waveform of the AC voltage V1.

  The current detection unit 5 detects and outputs a current waveform of an alternating current I1 (an alternating current having the same cycle as the alternating voltage V1) flowing in the detection circuit 50 in an application state of the alternating voltage V1 in a non-contact manner. As an example, the current detection unit 5 is configured in the same manner as the current detection circuit disclosed in the above-described Japanese Patent Application Laid-Open No. 2012-137497, and a magnetoelectric conversion element (for example, a magnetic flux such as a Hall element) disposed in the clamp arm 11. 5a, a magnetic core 5b disposed in the clamp arm 11, and an electric signal output from the magnetoelectric conversion element 5a are amplified and output as a voltage signal Vi. Current detection circuit 5c.

  In this case, the magnetic core 5b efficiently guides the magnetic flux generated around the detection electric circuit 50 to the magnetoelectric conversion element 5a due to the alternating current I1 flowing through the detection electric circuit 50 clamped by the clamp unit 2. Further, the magnetoelectric conversion element 5a outputs an electric signal having the same phase as the alternating current I1. Therefore, the current detection circuit 5c outputs the voltage signal Vi having the same phase as the alternating current I1 as a signal (alternating current signal) indicating the current waveform of the alternating current I1.

  The direction of the magnetic flux generated around the detection electric circuit 50 is reversed when the direction of the alternating current I1 flowing through the clamped detection electric circuit 50 is changed. For this reason, the magnetoelectric conversion element 5a is in the first direction (the direction of the arrow A in FIGS. 2 and 3; the direction of the arrow mark 31a described later as an example in this example) on the detection electric circuit 50 in which the alternating current I1 is clamped. A second direction (the direction of arrow B in FIGS. 2 and 3, which is opposite to the first direction) of alternating current I <b> 1 in detection circuit 50 with respect to the phase when it is flowing. The electrical signal is output in a state where the phase when flowing in the direction (31b) is opposite. Thereby, the current detection circuit 5c (that is, the current detection unit 5) outputs the voltage signal Vi whose phase is inverted when the direction of the alternating current I1 flowing through the clamped detection circuit 50 is changed.

  The phase of the alternating current I1 flowing through the detection circuit 50 with respect to the alternating voltage V1 is based on the phase of the alternating voltage V1 depending on whether the detection circuit 50 is connected to an inductive load or a capacitive load. As a result, it changes in a range from minus (−) 90 ° to plus (+) 90 °. In this example, as an example, when the alternating current I1 flows in the clamped detection circuit 50 in the first direction A, the current detection unit 5 uses the phase of the voltage waveform of the voltage signal Vv for the alternating voltage V1 as a reference. As described above, the voltage signal Vi for the alternating current I1 is output in a phase difference state within a range of minus 90 ° to plus 90 °. Therefore, when the alternating current I1 flows in the clamped detection circuit 50 in the second direction B, the current detection unit 5 is plus 90 ° or more plus 270 ° with reference to the phase of the voltage waveform of the voltage signal Vv. A voltage signal Vi for the alternating current I1 is output in a phase difference state within the following range.

  The first binarization unit 6 is configured by a comparator, for example, and receives the voltage signal Vv as an AC signal, and also converts the voltage signal Vv into a binarization signal (duty ratio) with reference to a reference potential (ground potential, zero volts). Is 0.5, a voltage pulse having the same cycle as the AC voltage V1) S1 is converted and output. Specifically, when the voltage signal Vv is less than the reference potential (that is, when the voltage signal Vv is a negative voltage), the first binarization unit 6 is detected as logic low in the subsequent processing unit 8. When the voltage level is zero volts and the voltage signal Vv is equal to or higher than the reference potential (that is, when the voltage signal Vv is a positive voltage), the voltage level detected by the processing unit 8 as logic high (the power supply voltage of the processing unit 8) The binarized signal S1 having a voltage level close to (2) is output to the processing unit 8.

  The second binarization unit 7 is configured by a comparator, for example, and receives the voltage signal Vi as an AC signal, and also converts the voltage signal Vi into a binarized signal (duty ratio) with reference to a reference potential (ground potential, zero volts). Is 0.5, a voltage pulse having the same cycle as the alternating current I1) S2 and output. Specifically, when the voltage signal Vi is less than the reference potential (that is, when the voltage signal Vi is a negative voltage), the second binarization unit 7 detects a logic low in the subsequent processing unit 8. When the voltage level is zero volts and the voltage signal Vi is equal to or higher than the reference potential (that is, when the voltage signal Vi is a positive voltage), the voltage level detected by the processing unit 8 as logic high (the power supply voltage of the processing unit 8) The binarized signal S2 having a voltage level close to (2) is output to the processing unit 8.

  As an example in this example, the processing unit 8 inputs two binarized signals S1 and S2 and a logical product signal S3 indicating the logical product of these binarized signals S1 and S2, as shown in FIG. And a direction detection circuit 22 for detecting the duty ratio of the logical product signal S3 and detecting the power transmission direction in the detection circuit 50 based on the detected duty ratio. The processing unit 8 receives the two binarized signals S1 and S2 and detects whether the phase of the binarized signal S2 is advanced with respect to the phase of the binarized signal S1. A detection circuit 23 is provided.

  Specifically, the AND circuit 21 includes, for example, a 2-input AND operation element, and generates an AND signal S3 indicating the AND of the binarized signals S1 and S2, for example, positive logic (binarization). The logic of the signals S1 and S2 is output only when the logic of the signals S1 and S2 is both High. Of course, the logical product circuit 21 may output a logical product signal S3 indicating the logical product of the binarized signals S1 and S2 in negative logic.

  Specifically, for example, the direction detection circuit 22 includes two counters that operate with a clock having a sufficiently high frequency with respect to the frequency of the AC voltage V1 and the AC current I1, and a logical product based on the count value of each counter. Whether or not the duty ratio of the signal S3 is 0.25 or more is detected, and when the duty ratio is 0.25 or more, the first detection signal S4 is output, and when the duty ratio is less than 0.25, the second detection is performed. And an arithmetic circuit (none of which is shown) for outputting the signal S5.

  In this case, for example, one of the two counters counts in synchronization with the clock immediately after the input start timing of the logical product signal S3 (at the time of positive logic, the timing of changing from logic low to logic high). Is reset, the count operation is started from the next clock, and this count operation is executed only during the input period of the logical product signal S3. That is, this one counter detects the pulse width of the logical product signal S3. On the other hand, the counter value of the other counter of the two counters is reset in synchronization with the clock immediately after the input start timing of the logical product signal S3 (at the time of positive logic, the timing when the logic low changes to the logic high). At the same time, the count operation is started from the next clock, and this count operation is executed until the next new logical product signal S3 is input (until the count value is reset next). That is, the other counter detects the cycle of the logical product signal S3.

  The arithmetic circuit is provided for every two counters, for example, a latch that inputs and holds the count value of each counter in synchronization with the clock of the counter, and a latch that holds the count value of one of the counters A shift register that quadruples the count value by inputting two outputs after the input of the logical product signal S3 and before the input of the next new logical product signal S3, and As an example, the output of the shift register is compared with the count value of the other counter in synchronization with the timing at which the count value of each counter is reset, and when the output of the shift register is equal to or greater than the count value of the other counter (that is, When the duty ratio of the logical product signal S3 is 0.25 or more), the first detection signal S4 is output, and the output of the shift register is the count of the other counter. When (i.e., the duty ratio of the logical product signal S3 when less than 0.25) than in and a comparator which outputs a second detection signal S5.

  Specifically, as an example, the phase detection circuit 23 operates by using the binary signal S1 of the voltage signal Vv as a clock, and holds one logic state for the binary signal S2 of the voltage signal Vi. It consists of With this configuration, the phase of the binarized signal S2 with a duty ratio of 0.5 is advanced in the same cycle as the binarized signal S1 with respect to the phase of the binarized signal S1 with a duty ratio of 0.5. In the phase state, the binarized signal S2 at the rising timing of the binarized signal S1 is in a logic state in which the logic is High. On the other hand, when the phase of the binarized signal S2 is delayed with respect to the phase of the binarized signal S1, the binarized signal S2 at the rising timing of the binarized signal S1 is in a logic state in which the logic is low. It becomes. Therefore, the phase detection circuit 23 composed of D-FF outputs the third detection signal S6 whose logic is High from the Q output terminal when the phase of the binarized signal S2 is advanced, and the binary signal S2 is binary. When the phase of the signal S2 is delayed, the fourth detection signal S7 whose logic is High is output from the QB (Q bar) output terminal.

  The specific examples of the direction detection circuit 22 and the phase detection circuit 23 described above are merely examples, and the direction detection circuit 22 and the phase detection circuit 23 can be configured by combining other known logic circuits. Further, the direction detection circuit 22 is constituted by a CPU, and the duty ratio of the logical product signal S3 calculated from the detection of the pulse width and cycle of the logical product signal S3 and the pulse width and cycle of the logical product signal S3 is 0. The detection of whether or not 25 or more may be executed by software to output the first detection signal S4 and the second detection signal S5. When the direction detection circuit 22 is configured by a CPU, a configuration in which the CPU executes the software with respect to the function of the AND circuit 21 can also be adopted. The phase detection circuit 23 is also configured by a CPU, and the phase state of the binarized signal S2 with respect to the phase of the binarized signal S1 is executed by software, and the third detection signal S6 and the fourth detection signal S7 are output. You may make it do. In this case, the logical product circuit 21, the direction detection circuit 22, and the phase detection circuit 23 can be entirely constituted by a CPU.

  In this example, the output unit 9 includes a display unit such as an LCD (Liquid Crystal Display) (hereinafter also referred to as “display unit 9”). As shown in FIGS. 2 and 3, the display unit 9 includes, as an example, a first display unit 31 as a first output unit for displaying the power transmission direction of the detection electric circuit 50 clamped by the clamp unit 2. A second display unit 32 as a second output unit for displaying the phase state of the binarized signal S2 with respect to the phase of the binarized signal S1 (that is, the phase state of the alternating current I1 with respect to the phase of the AC voltage V1); It has. Note that the output unit 9 is not limited to the display unit, and may be configured by, for example, a transmission unit that transmits information (data) to an external device. When this configuration is adopted, the transmission unit is configured by including the first transmission unit as the first output unit and the second transmission unit as the second output unit, and information indicating the power transmission direction is obtained from the first transmission unit. In addition, information indicating the phase state is output from the second transmitter to an external device.

  Specifically, as an example, the first display unit 31 includes an arrow mark 31a and an arrow mark 31b that is arranged adjacent to and parallel to the arrow mark 31a and that indicates a direction opposite to the arrow mark 31a. It is configured to be displayable. The first display unit 31 shifts the arrow mark 31a to the display state when the first detection signal S4 is input from the direction detection circuit 22, and the arrow mark 31b when the second detection signal S5 is input. Transition to the display state. In addition, as shown in FIGS. 1, 2, and 3, the first display unit 31 is exposed when each arrow mark 31 a and 31 b is exposed from one side surface 3 a of the sensor body 3 and is clamped to the clamp unit 2. The sensor main body 3 is arranged so as to be parallel to the length direction of the detection electric circuit 50.

  In addition, in order to display the power transmission direction of the detection electric circuit 50, although it described above about the example which comprises the 1st display part 31 so that a pair of arrow mark 31a, 31b which shows a mutually reverse direction can be displayed, it is not limited to this, For example, the first display unit 31 can be configured to selectively light the arrow portion on the side corresponding to the power transmission direction of the detection electric circuit 50 in one arrow mark having arrows formed at both ends. A configuration can be employed.

  As an example, the second display unit 32 has a phase state in which the phase of the binarized signal S2 is advanced with respect to the phase of the binarized signal S1 (that is, the phase of the alternating current I1 is relative to the phase of the AC voltage V1). A mark 32a (in this example, the letter “LEAD” indicating this phase state) for displaying the advancing phase state) and the binarized signal S2 phase with respect to the phase of the binarized signal S1 A mark 32b for displaying a phase state in which the phase is delayed (that is, a phase state in which the phase of the alternating current I1 is delayed with respect to the phase of the alternating voltage V1) (in this example, a character indicating this phase state) "LAG" mark) can be displayed. The second display unit 32 shifts the mark 32a to the display state when the third detection signal S6 is input from the direction detection circuit 22, and displays the mark 32b when the fourth detection signal S7 is input. To migrate. In addition, as shown in FIGS. 1, 2, and 3, the second display unit 32 is disposed on the sensor body 3 so that the marks 32 a and 32 b are exposed from one side surface 3 a of the sensor body 3. Yes.

  In addition, in order to display the phase state of the alternating current I1 with respect to the phase of the AC voltage V1, an example in which the second display unit 32 is configured to be able to display marks 32a and 32b for displaying two characters corresponding to each phase state. As described above, the present invention is not limited to this. For example, the second display unit 32 can be configured so that marks for displaying two different colors corresponding to each phase state can be displayed. Can do.

  Next, operation | movement of the power transmission direction detection apparatus 1 is demonstrated. In the following, when the detection electric circuit 50 is clamped to the clamp portion 2 as shown in FIGS. 2 and 3, when the alternating current I1 flows in the detection electric circuit 50 in the first direction A, the alternating current I1 is The operation when flowing in the detection circuit 50 in the second direction B will be described separately.

  First, the operation for detecting the power transmission direction of the clamped detection circuit 50 (the direction of the alternating current I1 flowing through the detection circuit 50) will be described.

  First, the operation of the power transmission direction detection device 1 when the alternating current I1 flows in the detection electric circuit 50 in the first direction A will be described.

  In the power transmission direction detection device 1, as shown in FIG. 4, the voltage detection unit 4 detects the AC voltage V1 applied to the detection circuit 50, and has the same phase and the same polarity as the AC voltage V1. Vv is output. Further, the current detection unit 5 detects the alternating current I1 flowing through the detection electric circuit 50 and outputs a voltage signal Vi. Further, the first binarization unit 6 converts the voltage signal Vv into a binarization signal S1 and outputs it, and the second binarization unit 7 converts the voltage signal Vi into a binarization signal S2 and outputs it.

  In this case, since the alternating current I1 flows in the detection circuit 50 in the first direction A, the current detection unit 5 uses the 0 ° phase of the voltage signal Vv as a reference, as shown in FIG. As shown by the broken line, the phase advances by 90 ° at the maximum (the phase difference becomes plus 90 °), and the phase is delayed by 90 ° at the maximum as shown by the alternate long and short dash line in the figure (the phase difference becomes minus 90 °). The voltage signal Vi in any phase state between the phase states (including a phase state in which the phase difference is 0 ° as shown by a solid line in the figure) is output.

  For this reason, as shown in FIG. 4, the second binarization unit 7 also advances the phase by 90 ° at the maximum with the phase of the binarization signal S1 output from the first binarization unit 6 as a reference (position). Any phase state between the phase state in which the phase difference is plus 90 ° and the phase state in which the phase is delayed by 90 ° at the maximum (the phase difference is minus 90 °) (the phase state in which the phase difference is 0 °) 2) is output.

  In the processing unit 8, the logical product circuit 21 receives the binarized signals S1 and S2 and outputs a logical product signal S3 indicating the logical product of these signals. When the alternating current I1 flows in the clamped detection circuit 50 in the first direction A, the binarized signal S2 is in the phase state (the binarized signal S1 of the binarized signal S1) with respect to the binarized signal S1. The phase difference is output within the range of minus 90 ° or more and plus 90 ° or less with respect to the phase. Therefore, as shown in FIG. 4, the duty ratio of the logical product signal S3 is such that the phase of the binarized signal S2 is 0 ° (phase difference is 0 °) with respect to the phase of the binarized signal S1. It becomes maximum (0.5) and becomes smaller as the phase shifts to the minus side or plus side, and becomes minimum (0.25) when the phase difference is minus 90 ° and when the phase difference is plus 90 °. That is, when the alternating current I1 flows in the clamped detection circuit 50 in the first direction A, the duty ratio of the logical product signal S3 is 0.25 or more and 0.5 or less.

  In the processing unit 8, the direction detection circuit 22 detects whether or not the duty ratio of the logical product signal S3 is 0.25 or more, and is 0.25 or more. The first detection signal S4 is output, and the output of the second detection signal S5 is stopped.

  Thereby, in the display part 9, the 1st display part 31 inputs 1st detection signal S4, the arrow mark 31a which shows the same direction as the 1st direction A is changed to a lighting state, On the other hand, 2nd detection Since the signal S5 is not input, the arrow mark 31b is shifted to the off state.

  Next, the operation of the power transmission direction detection device 1 when the alternating current I1 flows in the detection electric circuit 50 in the second direction B will be described.

  In the power transmission direction detection device 1, as shown in FIG. 5, the voltage detection unit 4 detects the AC voltage V1 applied to the detection circuit 50, and is a voltage signal having the same phase and polarity as the AC voltage V1. Vv is output. Further, the current detection unit 5 detects the alternating current I1 flowing through the detection electric circuit 50 and outputs a voltage signal Vi. Further, the first binarization unit 6 converts the voltage signal Vv into a binarization signal S1 and outputs it, and the second binarization unit 7 converts the voltage signal Vi into a binarization signal S2 and outputs it.

  In this case, since the alternating current I1 flows in the detection circuit 50 in the second direction B, the current detection unit 5 uses the + 180 ° phase of the voltage signal Vv as a reference, as shown in FIG. As shown by the broken line, the phase advances by 90 ° at the maximum (the phase difference from the voltage signal Vv becomes minus 90 °), and as shown by the alternate long and short dash line in FIG. Any phase state between the phase state and the voltage signal Vv (including the phase state in which the phase difference from the voltage signal Vv is minus 180 ° as shown by the solid line in the figure). The voltage signal Vi at is output.

  For this reason, as shown in FIG. 5, the second binarization unit 7 also uses the phase of the binarized signal S1 output from the first binarization unit 6 as a reference and the phase difference from the binarized signal S1. Any phase state between the phase state in which the phase difference is minus 90 ° and the phase state in which the phase difference between the binarized signal S1 is minus 270 ° (the phase difference from the binarized signal S1 is minus 180 °) The binarized signal S2 in the phase state (including the above) is output.

  In the processing unit 8, the logical product circuit 21 receives the binarized signals S1 and S2 and outputs a logical product signal S3 indicating the logical product of these signals. When the alternating current I1 flows in the clamped detection circuit 50 in the second direction B, the binarized signal S2 is in the phase state (the binarized signal S1 of the binarized signal S1) with respect to the binarized signal S1. With respect to the phase, the phase difference is output within a range of minus 90 ° to minus 270 °). For this reason, as shown in FIG. 5, the duty ratio of the logical product signal S3 becomes minimum (0) when the phase difference of the binarized signal S2 with respect to the phase of the binarized signal S1 is minus 180 °. From this phase state, the phase increases as the phase shifts to the plus side or minus side, and becomes maximum (0.25) when the phase difference is minus 90 ° and when the phase difference is minus 270 °. That is, when the alternating current I1 flows in the clamped detection circuit 50 in the second direction B, the duty ratio of the logical product signal S3 is less than 0.25.

  In the processing unit 8, the direction detection circuit 22 detects whether or not the duty ratio of the logical product signal S3 is 0.25 or more and is less than 0.25. Therefore, as shown in FIG. The output of the first detection signal S4 is stopped and the second detection signal S5 is output.

  Thereby, in the display part 9, the 1st display part 31 inputs 2nd detection signal S5, the arrow mark 31b which shows the same direction as the 2nd direction B is changed to a lighting state, On the other hand, 1st detection Since the signal S4 is not input, the arrow mark 31a is shifted to the off state.

  Thus, in this power transmission direction detection device 1, only the arrow mark in the same direction as the direction of the alternating current I1 flowing in the clamped detection electric circuit 50 among the two arrow marks 31a and 31b of the first display unit 31 is lit. Therefore, based on the lighting state of the arrow marks 31a and 31b, it is possible to detect the direction of the alternating current I1 (power transmission direction (power flow direction)) flowing through the clamped detection circuit 50.

  Subsequently, the phase state of the AC current I1 with respect to the phase of the AC voltage V1 applied to the detection circuit 50, that is, the phase state in which the phase of the AC current I1 is advanced with reference to the phase of the AC voltage V1 of 0 ° ( A phase state in which the phase difference is any of 0 ° to plus 90 °) or a phase state in which the phase of the alternating current I1 is delayed (a phase in which the phase difference is between 0 ° and minus 90 °). The operation for detecting whether the state is a state will be described.

  In this case, as shown in FIG. 4, the phase of the alternating current I1 advances by 90 ° at the maximum (the phase difference becomes plus 90 °) with respect to the phase of 0 ° of the AC voltage V1, and the maximum of 90 °. In order to be in any phase state between the delayed phase state (the phase difference is minus 90 °), that is, as described above, the alternating current I1 flows in the first direction A (that is, the arrow It is necessary to clamp the detection electric circuit 50 with the power transmission direction detection device 1 so that the mark 31a is lit.

  Therefore, when the direction of the alternating current I1 flowing in the detection electric circuit 50 detected by clamping with the power transmission direction detection device 1 is in the first direction A (that is, the direction in which the arrow mark 31a is lit), the clamped state may remain. However, when the detected direction of the alternating current I1 is in the second direction B (that is, the direction in which the arrow mark 31b is lit), the direction of the alternating current I1 and the arrow mark 31a coincide with each other. Is re-clamped to the detection circuit 50.

  Thus, when the alternating current I1 is flowing in the clamped detection circuit 50 in the first direction A (that is, the arrow mark 31a is lit), the power transmission direction detection device 1 uses the phase. The detection circuit 23 outputs one of the third detection signal S6 and the fourth detection signal S7 based on the logic state of the binary signal S2 at the rising timing of the binary signal S1.

  Specifically, the phase detection circuit 23 is in the case where the phase of the binarized signal S2 is advanced with respect to the phase of the binarized signal S1 (when the phase difference is greater than 0 ° and less than 90 °). As shown in FIG. 4, the logic state of the binarized signal S2 at the rising timing of the binarized signal S1 becomes High. Therefore, the phase detection circuit 23 outputs the third detection signal S6 and stops outputting the fourth detection signal S7. Thereby, in the display unit 9, the second display unit 32 inputs the third detection signal S6, shifts the mark 32a (mark of the character “LEAD”) to the lighting state, and moves the mark 32b (mark of the character “LAG”). Mark) is turned off.

  On the other hand, when the phase of the binarized signal S2 is delayed with respect to the phase of the binarized signal S1 (when the phase difference is less than 0 ° and minus 90 ° or more), the phase detection circuit 23 is shown in FIG. As shown, the logic state of the binarized signal S2 at the rising timing of the binarized signal S1 becomes Low. Therefore, the phase detection circuit 23 outputs the fourth detection signal S7 and stops outputting the third detection signal S6. Thereby, in the display unit 9, the second display unit 32 inputs the fourth detection signal S7, shifts the mark 32b (mark of the character “LAG”) to the lighting state, and moves the mark 32a (character “LEAD”). Mark) is turned off.

  As described above, in this power transmission direction detection device 1, when the direction of the alternating current I1 in the clamped detection circuit 50 is the first direction A, the phase of the binarized signal S2 with respect to the phase of the binarized signal S1 It is also possible to accurately detect the state, that is, the phase state of the alternating current I1 with respect to the phase of the alternating voltage V1 (whether the phase of the alternating current I1 is advanced or delayed with respect to the phase of the alternating voltage V1). Yes.

  Thus, according to the power transmission direction detection device 1, as described above, the voltage detection unit 4, the current detection unit 5, the binarization units 6 and 7, the processing unit 8, and the display unit 9 are provided. The power transmission direction of the detection electric circuit 50 can be detected in a non-contact manner and displayed on the display unit 9 without executing the process of calculating the effective power transmitted through the detection electric circuit 50. Therefore, the operator can surely recognize the power transmission direction of the detection circuit 50 based on the display content of the display unit 9 (in this example, the lighting state of the arrow marks 31a and 31b).

  Moreover, according to this power transmission direction detection apparatus 1, the 2nd display part 32 in this state is clamped by the power transmission direction detection apparatus 1 to the detection electric circuit 50 so that the detected power transmission direction and the arrow mark 31a may correspond. Based on the lighting state of each of the marks 32a and 32b, the phase state of the alternating current I1 with respect to the phase of the alternating voltage V1 (whether the phase of the alternating current I1 is advanced or delayed with respect to the phase of the alternating voltage V1) is contactless. Can be detected.

  Note that the power transmission direction detection device 1 includes the phase detection circuit 23 and the second display unit 32 and can detect the phase state of the alternating current I1 with respect to the phase of the alternating voltage V1 in a non-contact manner. When only the function of detecting the power transmission direction of the electric circuit 50 is sufficient, the phase detection circuit 23 and the second display unit 32 may be omitted, and the function of detecting the phase state of the alternating current I1 with respect to the phase of the alternating voltage V1 may be omitted. .

DESCRIPTION OF SYMBOLS 1 Power transmission direction detection apparatus 4 Voltage detection part 5 Current detection part 6 1st binarization part 7 2nd binarization part 8 Processing part 9 Display part 31 1st display part 32 2nd display part 50 Detection electric circuit 50
I1 AC current S1, S2 Binary signal V1 AC voltage Vi, Vv Voltage signal

Claims (2)

A voltage detection unit that detects and outputs a voltage waveform of an AC voltage applied to the detection circuit without contact, and detects a current waveform of an AC current flowing through the detection circuit without contact while the AC voltage is applied. The detected current waveform is a phase when the alternating current is flowing in the second direction opposite to the first direction with respect to the phase when the alternating current is flowing in the detection circuit in the first direction. A power transmission direction detection device that detects a power transmission direction in the detection circuit based on the detected voltage waveform and the current waveform, and a current detection unit that outputs in a state of being in reverse phase,
When the alternating current is flowing in the first direction, the current detection unit outputs the current waveform in a phase difference state within a range of minus 90 ° to plus 90 ° with respect to the phase of the voltage waveform. And
A first binarization unit that binarizes the voltage waveform with reference to zero volts and outputs a first binarization signal;
A second binarization unit that binarizes the current waveform on the basis of zero amperes and outputs a second binarized signal;
When the duty ratio for the logical product of the first binarized signal and the second binarized signal is 0.25 or more, it is detected that the power transmission direction is the first direction, and the duty ratio is 0. 0. When the power transmission direction is less than 25, the processing unit detects that the power transmission direction is the second direction;
A power transmission direction detection apparatus comprising: a first output unit that outputs information on the power transmission direction detected by the processing unit. Based on the logic of the second binarized signal when the first binarized signal rises, the processing unit delays the phase of the AC current with respect to the phase of the AC voltage when the logic is Low. And when the logic is High, it is detected that the phase of the AC current is advanced with respect to the phase of the AC voltage,
The power transmission direction detection device according to claim 1, further comprising: a second output unit that outputs information on the state of the phase of the AC current with respect to the phase of the AC voltage detected by the processing unit.
Place.

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