JP2006184090A - Method and device for measuring and circuit breaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To acquire phase wire type information of a cable way in order to acquire various electrical quantity information only by performing a simple operation without setting or manipulating. <P>SOLUTION: This device is equipped with a sample hold circuit 23 for holding sampling values of various electrical quantities of the cable way, an A/D conversion part 27 for performing successively A/D conversion of each sampling electrical quantity held in the sample hold circuit 23, and an operation device 26 for inputting a digital output from the A/D conversion part 27 and operating a necessary electrical quantity of the cable way. In the device, the phase wire type is discriminated from a voltage between input lines, and the various electrical quantities are operated by the operation device corresponding to the phase wire type acquired by discrimination and then displayed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a measurement method, a measurement apparatus, and a circuit breaker that perform at least one of display and communication of energization information obtained by calculating various electric quantities corresponding to a phase wire type of an electric circuit.

  There are various types of phase wire represented by single-phase two-wire, single-phase three-wire, three-phase three-wire, and three-phase four-wire, depending on the load device to be connected. There are various measuring devices that measure and display the current-carrying information of these electric circuits, that is, current, voltage, electric energy, power factor, etc., but the measurement / display conforms to the phase line type of the electric circuit. Needless to say, you have to. Therefore, although it is conceivable to prepare these measuring devices in accordance with the phase line type of the electric circuit to be arranged, it is difficult to say that it is very advantageous from the viewpoint of product standardization. Therefore, a changeover switch that can be set from the outside is provided in the device (for example, refer to Patent Document 1), or a nonvolatile memory in which rating information is stored is built in the device, and the setting is automatically performed by communication from the central device, for example. (For example, refer to Patent Document 2).

  In order to obtain information on the state of various quantities of electricity in the circuit, it is indispensable to install a primary current transformer and a measurement transformer in the circuit, but these primary current transformers and measurement transformers There must be no misconnections between the measuring devices. As a means for recognizing this erroneous connection, first, a phase line type is set for the device (described as “determination device” in Patent Documents 3 and 4 to be described later), and then the phase difference between the voltage and current is calculated. Detect and determine whether this phase difference is within a specified value (see, for example, Patent Document 3), or calculate the phase angle by Fourier transforming waveform data obtained by sampling each line voltage, There is a method of determining whether or not the phase angle matches the phase angle obtained by the selected phase wire system (see, for example, Patent Document 4).

JP-A-8-317476 (page 6, right column, lines 2 to 19) JP 2004-85413 A (right column on page 3, line 3 to line 8) JP 2000-162299 A (page 4, right column, lines 9 to 16) JP 2000-258484 A (right column on page 5, line 33 to line 40)

  In a conventional measuring device, the phase line type of the electric circuit measured by the measuring device is set by a dip switch or the like provided in the measuring device, or the measuring device recognizes it by transmission means from the central device. In any case, the troublesome operation or setting cannot be avoided. Moreover, there may be a case where the energization information is not displayed correctly if a setting omission or an incorrect setting occurs. In addition, as a method that can omit these settings, use the above-described phase difference detection method described in Patent Documents 3 and 4 above or the phase angle calculation after Fourier transform to obtain phase-line information of the electric circuit. Although it is possible to incorporate this method into the measuring device itself, as a result, a large number of repetitive calculations are required, which increases the calculation time. The problem of having to use a simple microcomputer occurs. In particular, in the case where there is a low possibility of erroneous connection, for example, in the case where the primary current transformer and the measurement transformer are provided in the circuit breaker together with the measurement device, it is costly to adopt such a method. It ’s hard to say that it ’s a good idea.

  The present invention has been made to solve the above-described problems. Phase line information of an electric circuit for obtaining various electric quantity information by simply performing a simple calculation without performing setting or operation. It is intended to be able to acquire.

  The measurement method according to the present invention is a measurement device that displays at least one of energization information and communication obtained by calculating various electric quantities corresponding to the phase line type of the electric circuit. Is determined, and various electric quantities are calculated and displayed in accordance with the phase and wire type obtained by the determination.

  In addition, the measuring device according to the present invention includes a sample hold circuit that holds sampling values of various electric quantities of the electric circuit, an A / D conversion unit that sequentially A / D converts the sampling electric quantities held in the sample hold circuit, And an arithmetic unit that inputs the digital output of the A / D converter and calculates the necessary amount of electricity of the electric circuit, and determines the phase line type from the input line voltage and corresponds to the phase line type obtained by the determination Then, it is a measuring device that calculates and displays various amounts of electricity by a calculation device.

  In addition, the circuit breaker according to the present invention executes a measuring method for calculating and displaying various electric quantities corresponding to the phase wire type obtained by the determination after determining the phase line type from the input line voltage. A circuit breaker having a function to

  In addition, a circuit breaker according to the present invention includes a sample hold circuit that holds sampling values of various electric quantities in an electric circuit, and an A / D converter that sequentially A / D converts the sampling electric quantities held in the sample hold circuit. And an arithmetic unit that inputs the digital output of the A / D converter and calculates a necessary amount of electricity of the electric circuit, determines the phase line type from the input line voltage, and obtains the phase line type obtained by the determination. Correspondingly, it is a circuit breaker provided with a measuring device for calculating and displaying various electric quantities by an arithmetic device.

  The present invention relates to a measurement device that displays at least one of energization information and communication obtained by calculating various electric quantities corresponding to the phase and wire type of the electric circuit, and then determines the phase and wire type from the input line voltage. This is a measurement method that calculates and displays various electric quantities corresponding to the phase and wire type obtained by the discrimination. Also, a sample hold circuit that holds sampling values of various electric quantities on the electric circuit, and holds in this sample hold circuit. An A / D converter for sequentially A / D converting a sampling electric quantity, and an arithmetic unit for inputting a digital output of the A / D converter and calculating a necessary electric quantity of the electric circuit, and an input line voltage Is a measuring device that determines the phase wire type from the input and calculates and displays various amounts of electricity by the arithmetic unit corresponding to the phase wire type obtained by the determination, and also determines the phase line type from the input line voltage Later A circuit breaker with a function to execute a measurement method that calculates and displays various electric quantities corresponding to the phase and wire type obtained separately, and also holds a sampling value of various electric quantities on the electric circuit A hold circuit, an A / D converter that sequentially A / D converts the sampling electric quantity held in the sample hold circuit, and a digital output of the A / D converter are inputted to calculate a necessary electric quantity of the electric circuit A circuit breaker having a measuring device for determining the phase wire type from the input line voltage and calculating and displaying various electric quantities by the calculating device corresponding to the phase wire type obtained by the determination Therefore, a user-friendly measurement method, a measurement device, and a circuit breaker are obtained, and a manufacturer is provided with an economical measurement device and a circuit breaker. Can.

Embodiment 1 FIG.
A first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a schematic circuit diagram, and FIG. 2 is a flowchart of a phase wire type discrimination process.

  1 and 2 are diagrams illustrating a procedure for discriminating a phase line type based on voltage information obtained from a measurement transformer disposed on a current-carrying conductor in Embodiment 1 of the present invention. In the figure, (a) is a single-phase two-wire system, (b) is a single-phase three-wire system or three-phase three-wire system, and (c) is a three-phase four-wire circuit example.

  In FIG. 1, for convenience, the energizing conductor 4 is denoted by 1 · 2, 3 · N from the left side to the right side in the drawing. A measuring transformer 16 is disposed between the lines of the conducting conductor 4, and voltage signals obtained from the measuring transformer 16 are V12 in the case of the single-phase two-wire system (a). (Line voltage between current-carrying conductor (symbol 1) and current-carrying conductor (symbol 2)), V12 and V23 (current-carrying conductor (symbol 2) in the case of single-phase three-wire system or three-phase three-wire system (b)) Between the current-carrying conductor (symbol 3) and the three-phase four-wire system (c), V12, V23, and V2N (between the current-carrying conductor (symbol 2) and the current-carrying conductor (symbol N)) Line voltage).

  Subsequently, according to FIG. 2, from the voltage signal of the line voltage obtained from the output of the instrument transformer, the circuit is one of the phase wire type (a) to (c) and the phase wire type (b). In this case, the process up to the determination of single phase or three phase will be described.

  First, the presence or absence of V2N is determined by a microcomputer (not shown) (S1). If V2N is present, it is recognized that the circuit is a three-phase four-wire system. If V2N is not present, it is next determined whether or not V23 is present (S2). Here, if there is no V23, it is recognized that the circuit is a single-phase two-wire system, and if V23 is present, then this V23 is generated between V12 and V31, ie, 3-1. The voltage signal corresponding to the voltage is compared (S3). At this time, if V12, V23, and V31 are substantially equal, the circuit is recognized as a three-phase three-wire system, and if this relationship does not hold, it is recognized as a single-phase three-wire system.

  Thus, by utilizing the presence or absence of the line voltage or the relationship thereof, the phase line type of the electric circuit can be easily obtained. For S3, the same result can be obtained even if the flow is recognized as a single-phase three-wire system if the sum of V12 and V23 is substantially equal to V31, and a three-phase three-wire system if they are not equal. Needless to say.

  Further, Embodiment 1 of the present invention is a measurement apparatus that displays at least one of energization information obtained by calculating various amounts of electricity corresponding to the phase wire type of the electric circuit and performs communication from the input line voltage. This is a measurement method for calculating and displaying various electric quantities corresponding to the phase and wire type obtained by the discrimination after discriminating the phase and wire type.

Embodiment 2. FIG.
A second embodiment of the present invention will be described below with reference to FIGS. FIG. 3 is a block diagram showing the configuration of a circuit breaker with an energization information measuring / displaying device, FIG. 4 is a flowchart showing the operation of the microcomputer in FIG. 3, and FIG. 5 is a flowchart of the phase line type discrimination processing in FIG.

  In the second embodiment of the present invention, the basic concept described in the first embodiment described above is incorporated into a measuring device, that is, a more practical use is described as a second embodiment. In the second embodiment, the measurement device is a circuit breaker with an energization information measurement display device (hereinafter abbreviated as a circuit breaker) mounted on a three-phase four-wire wiring circuit breaker, and FIG. FIG. 4 is a flowchart showing the operation of the microcomputer, and FIG. 5 is each example of a flowchart of the phase wire type discrimination process.

  In FIG. 3, the circuit breaker unit 1 of the circuit breaker 101 is provided with a power supply side terminal 2 for the power supply side of the electric circuit to be attached, and a load side terminal 5 for the load side, and an energizing conductor that connects these terminals. Four sets of 4 are provided. As in the first embodiment, for the sake of convenience, reference numerals 1, 2, 3, and N are assigned from the left side to the right side in the figure. The current-carrying conductor 4 includes an open / close contact 3 for turning on and off the current flowing through the current-carrying conductor 4 by the electromagnetic device 14 and a primary current transformer 6 for detecting a current signal proportional to the current, as many as the number of poles of the circuit breaker 101. (In this case, 4).

  The current signal detected by the primary current transformer 6 is sent to the rectifier circuit 7, and the current signal rectified and waveform-shaped by the rectifier circuit 7 is instantaneously transmitted via the peak value conversion circuit 8 according to its magnitude. It is sent to the circuit 10 or the short time limit circuit 11 or to the long time limit circuit 12 via the effective value conversion circuit 9. In the instantaneous circuit 10, the short time limit circuit 11, and the long time limit circuit 12, when a predetermined time elapses after the operation, a trigger signal is output to the trigger circuit 13, and the electromagnetic signal is transmitted via the trigger circuit 13. It is well known that when the device 14 is excited, the switching contact 3 is cut, that is, the circuit breaker 101 is cut off, and the abnormal current flowing in the electric circuit prevents the electric wires from being burned out. .

  The secondary current transformer disposed on the secondary side of the primary current transformer 6 that generates a current signal that is input to the current information input device 21 and the current signal input circuit 21 provided in the current information display device 20. A so-called measuring device is configured by the flow device 15 and the measuring transformer 16 that similarly generates a voltage signal input to the voltage signal input circuit 22. The secondary current transformers 15 are arranged for the number of poles (in this case, four), but the measuring transformer 16 is between 1-2, 2-3, as can be seen from FIG. And a total of three between 2-N. As described in the first embodiment, the voltage signal proportional to the voltage between 3-1, 1-N, and 3-N is the voltage signal input circuit 22 serving as a measurement point of the voltage signal. This is because detection is possible by changing the input terminal (that is, the secondary output side of the measurement transformer 16).

  The energization information measuring / displaying device 20 is configured by a circuit described below in addition to the current signal input circuit 21 and the voltage signal input circuit 22 described above. That is, when a hold signal is received from a microcomputer (arithmetic unit) 26, which will be described later, the current signal / voltage signal that has been subjected to waveform shaping and level conversion in the current signal input circuit 21 / voltage signal input circuit 22 is held. A signal selection circuit 24 that selects a current signal / voltage signal output from the sample hold circuit 23 according to a selection signal of a microcomputer 26 described later, and a current signal / voltage signal output from the signal selection circuit 24 matches the measurement range. The range amplifier circuit 25 to be amplified in this manner, the current signal / voltage signal output from the range amplifier circuit 25 is converted into a digital value by the built-in A / D conversion circuit 27, and each phase current / line voltage is sampled. By acquiring waveform data, each phase current effective value, each line voltage effective value, harmonic current, effective Force, the reactive power, power amount, reactive energy, the microcomputer 26 for calculating the current information such as power factor, a.

  Furthermore, a display circuit 28 that displays energization information output from the microcomputer 26, a communication interface (I / F) circuit 29 that relays communication data between an external device such as a personal computer (not shown) and the microcomputer 26, and the microcomputer 26 are time-consuming. Clock circuit 30 for obtaining the date and time necessary for measurement and calculation of electric energy, distinction between circuit breaker and earth leakage breaker, or circuit breaker information such as the number of poles, sensitivity and trip time Storage circuit 31 for storing operation conditions such as temperature adjustment values, measurement values such as integrated electric energy and maximum value, and operation switch circuit 32 for inputting setting operation information and display selection information to the microcomputer 26. And a power supply circuit 33 for supplying predetermined power necessary for the microcomputer 26 and each circuit described so far.

  Next, the operation of the microcomputer 26 will be described with reference to FIG. After a desired voltage is applied to the power supply circuit 33, first, preparation for the start of measurement, specifically, an initial setting process for reading information in the clock circuit 30 and the storage circuit 31 is executed. Whether or not (S11). If measurement has already been performed, each of the measurement, display, communication, storage, and the like of energization information of the circuit in which the circuit breaker 101 is arranged is performed according to the phase / line type information calculated in the phase / line type discrimination process described later. Repeat the calculation process. Note that each calculation process does not form a main part of the present invention, and thus detailed description thereof is omitted.

  In the measurement of the energization information described above, the root mean square (that is, the effective value) of the waveform data of each line voltage is repeatedly calculated, and abnormalities such as voltage drop of the circuit are promptly displayed. RMS value, that is, between 1-2, 2-3, 3-1, 1-N, 2-N, and 3-N (in addition, when N phase is concerned, it becomes a phase voltage) In S11, if it is the first time, it is calculated prior to the phase wire type discrimination process described later.

  Next, referring to FIG. 5, the phase / wire type discrimination process which is the main part of the present invention will be described. In the following description, for example, the voltage between 1-2 is expressed as V12.

  First, it is determined whether V1N, V2N, and V3N are equal to or greater than zero, that is, whether a voltage is generated (S21 to S23). If these V1N, V2N, and V3N are all generated, the circuit is recognized as a three-phase four-wire system. If any one of V1N, V2N, and V3N has not occurred, it is next determined whether or not V12 and V23 have occurred (S24, S25). If any one of V12 and V23 is not generated, the circuit is recognized as a single-phase two-wire system. Conversely, if both V12 and V23 are generated, V31 is inevitably generated, and the values of V12, V23, and V31 are compared (S26). As a result, if the values of V12, V23, and V31 are substantially equal, the circuit is recognized as a three-phase three-wire system, and if the values are not equal, a single-phase three-wire system is recognized.

  In this way, to the circuit breaker equipped with a measuring device that captures the current-carrying information of the electric circuit or the measuring device arranged in the electric circuit, the phase line information is transmitted in advance using a setting operation such as a dip switch or a personal computer. By simply starting up the measuring device without taking measures such as storing data, you can obtain the phase line type of the circuit that is already live, so that the correct energization information according to the phase line type of the circuit can be used for special operations. Can be displayed without asking the user. In addition, since the effective value of each line voltage necessary for normal display is utilized and only comparison and calculation are performed, no special calculation or time is required for obtaining the phase line expression. There is no need to improve the performance of the microcomputer. In other words, it is possible to expect a ripple effect such as providing a product with excellent cost.

  In S26, the determination is made as V12≈V23≈V31. However, as described in the first embodiment, V12 + V23≈V31 is set, and if Yes, the single-phase three-wire system is recognized, and if No, the three-phase three-wire system is recognized. It may be a flow. Further, in the case of a measuring device, connection to a measuring transformer arranged in an electric circuit is always performed, so whether or not the electric circuit is a three-phase four-wire type is only V2N described in the first embodiment. In the case of a circuit breaker, the number of poles of the circuit breaker and the number of electrical circuits (for example, two for a single-phase two-wire system and three for a three-phase three-wire system) do not always match. (For example, wiring between 2-N of a circuit breaker of a four-pole product with a single-phase two-wire system) is preferable, and the flow shown in FIG. 5 is preferably used.

  Furthermore, S11 is omitted, that is, initial setting processing → each phase / line-to-line voltage effective value measurement processing → phase wire type discrimination processing → energization information measurement processing, and after the operation switch processing, The initial setting process may include a flow of repeatedly performing the above-described steps, and each phase / line-to-line voltage effective value measurement process and phase-wire type determination process. In either case, the effect that the start-up time of the measuring device is slightly shortened can be expected.

Embodiment 3 FIG.
In the second embodiment, the phase wire type discrimination process is performed only once immediately after application of power to the measuring device. In this case, the power is supplied to the measuring device and connected to the circuit breaker. If the phase wire system of the electric circuit is changed, correct energization information cannot be displayed. Therefore, S11 is a flow that is performed a plurality of times during power supply, for example, every month or every six months. According to this, it is possible to make the energization information follow the phase line type after the change.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows Embodiment 1 of this invention, and is a circuit schematic diagram. It is a figure which shows Embodiment 1 of this invention, and is a flowchart of the phase wire type discrimination | determination process in FIG. It is a figure which shows Embodiment 2 of this invention, and is a block diagram which shows the structure of the circuit breaker with an electricity supply information measurement display apparatus. It is a figure which shows Embodiment 2 of this invention, and is a flowchart which shows the operation | movement of the microcomputer in FIG. It is a figure which shows Embodiment 2 of this invention, and is a flowchart of the phase wire type discrimination | determination process in FIG.

Explanation of symbols

3 Open / close contact,
4 Conducting conductor,
20 Energization information measurement display device,
23 Sample hold circuit,
26 microcomputer (arithmetic unit),
27 A / D conversion circuit,
28 display circuit,
29 Communication I / F circuit,
31 memory circuit,
33 Power supply circuit,
101 Circuit breaker.

Claims (7)

  In the measuring device that displays at least one of the energization information obtained by calculating various electric quantities corresponding to the phase line type of the electric circuit and communication, after determining the phase line type from the input line voltage, A measuring method characterized by calculating and displaying various electric quantities corresponding to the obtained phase wire type.   A sample hold circuit for holding sampling values of various electric quantities in the electric circuit, an A / D converter for sequentially A / D converting the sampling electric quantity held in the sample hold circuit, and a digital output of the A / D converter And calculating the necessary amount of electricity in the electric circuit, determining the phase wire type from the voltage between the input lines, and calculating various types of electricity with the calculation unit corresponding to the phase line type obtained by the determination Measuring device to display.   The measuring apparatus according to claim 2, wherein the phase wire type determination is performed when power is supplied.   The measuring apparatus according to claim 3, wherein the phase wire type discrimination is performed a plurality of times.   The measuring device according to any one of claims 2 to 4, wherein in the case of a three-wire system, a function is provided for determining whether it is a single-phase three-wire system or a three-phase three-wire system. Measuring device.   A circuit breaker having a function of executing the measurement method according to claim 1.   The circuit breaker provided with the measuring device as described in any one of Claims 2-5.

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