JP3850184B2 - Electricity meter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a watt-hour meter that calculates an electric energy from an alternating current and a voltage of a system to be measured.
[0002]
[Prior art]
FIG. 4 shows a configuration of a general watt-hour meter.
[0003]
The primary voltage 1 and the primary current 2 input to the watt-hour meter 400 are converted into a voltage signal and a current signal by the voltage input conversion unit 3 and the current input conversion unit 4, respectively. These signals are input to a power calculation unit (multiplication unit) 5 to output a power signal. This electric power signal is converted into electric energy by integration in the integrating unit 6, recorded in the electric energy recording unit 7, and displayed on the electric energy display unit 8.
[0004]
By the way, in the conventional watt-hour meter, the voltage signal is always detected unless the power supply source has a power failure. However, when this is zero or cannot be detected, the power amount is also determined to be zero inside the apparatus.
[0005]
And when the power supply source is a power failure, since the current is zero, the power is zero and it can be said that the metering is normal.
[0006]
[Problems to be solved by the invention]
However, the watt-hour meter device is normal, but in the state where the voltage signal that should be detected due to miswiring or mischief is not normally detected, the conventional watt-hour meter becomes impossible to measure accurately. It was impossible to determine whether the finally obtained measurement value was a normal measurement value or an abnormal measurement value.
[0007]
The present invention has been made in view of such conventional points, and an object thereof is to provide a watt-hour meter capable of determining whether or not an abnormal measurement value is included.
[0008]
[Means for Solving the Problems]
The present invention according to claim 1 detects the AC voltage and AC current of the circuit to be measured, calculates the signals corresponding to them, converts them into signals proportional to the power, and accumulates them to measure the amount of power. In the single-phase or multi-phase watt-hour meter, a means for determining an abnormal state by detecting that the AC voltage value exceeds a preset upper limit value or lower limit value, and an abnormal state by this means And means for measuring the amount of electric power during the determination.
[0009]
The present invention according to claim 2 detects the AC voltage and AC current of the circuit to be measured, calculates signals corresponding to them, converts them into signals proportional to power, and accumulates them to measure the amount of power. In the single-phase or multi-phase watt hour meter, the means for determining the abnormal state by detecting that the frequency of the AC voltage exceeds the preset upper limit value or lower limit value, and this means And means for measuring the amount of electric power while it is determined to be present.
[0010]
According to the third aspect of the present invention, the AC voltage and AC current of the circuit to be measured are detected, the signals corresponding to these are calculated and converted into signals proportional to the power, and this is accumulated to measure the amount of power. In the multiphase watt-hour meter, a means for determining an abnormal state by detecting that the phase difference of the AC voltage between the phases exceeds a preset upper limit value or lower limit value, and this means And means for measuring the amount of electric power while it is determined to be present.
[0011]
According to the first to third aspects of the present invention having such a configuration, it is possible to separate the normal state and abnormal state measurements, and to obtain a normal state electric energy measurement value with high accuracy.
[0012]
The present invention according to claim 4 detects the AC voltage and AC current of the circuit to be measured, calculates signals corresponding to them, converts them into signals proportional to power, and accumulates them to measure the amount of power. In the single-phase or multi-phase watt-hour meter, a means for determining an abnormal state by detecting that the AC voltage value exceeds a preset upper limit value or lower limit value, and an abnormal state by this means And means for measuring the integrated current value during the determination.
[0013]
The present invention according to claim 5 detects the AC voltage and AC current of the circuit to be measured, calculates signals corresponding to them, converts them into signals proportional to power, and accumulates them to measure the amount of power. In the single-phase or multi-phase watt hour meter, the means for determining the abnormal state by detecting that the frequency of the AC voltage exceeds the preset upper limit value or lower limit value, and this means And a means for measuring an integrated current value during the determination.
[0014]
The present invention according to claim 6 detects the AC voltage and AC current of the circuit to be measured, calculates signals corresponding to them, converts them into signals proportional to power, and accumulates them to measure the amount of power. In the multiphase watt-hour meter, a means for determining an abnormal state by detecting that the phase difference of the AC voltage between the phases exceeds a preset upper limit value or lower limit value, and this means And a means for measuring an integrated current value during the determination.
[0015]
According to the present invention described in claims 4 to 6, the integrated current value during the abnormal state can be measured, and the power value during the abnormal state is assumed from the integrated current value. be able to.
[0016]
According to a seventh aspect of the present invention, there is provided the watt-hour meter according to any one of the first to sixth aspects, wherein the watt hour meter records a type of an event that is in an abnormal state when it is determined as an abnormal state. It is provided with.
[0017]
With such a configuration, it is possible to determine the type of event (abnormal voltage value, frequency abnormality, phase difference abnormality, etc.) that has become an abnormal state from the recording.
[0018]
The present invention according to claim 8 detects the AC voltage and AC current of the circuit to be measured, calculates signals corresponding to them, converts them into signals proportional to the power, and accumulates them to measure the amount of power. In a single-phase or multi-phase watt-hour meter, the means for detecting that the AC voltage is in a state below a certain value that can be regarded as an open phase, and the integrated current during which the state is detected by this means And a means for measuring the value.
[0019]
With such a configuration, the integrated current value during the open phase state can be measured, and the power value during the open phase state can be assumed from the integrated current value.
[0020]
The present invention according to claim 9 detects the AC voltage and AC current of the circuit under test, calculates the signals corresponding to them, converts them into signals proportional to the power, and accumulates them to measure the amount of power. If the phase of the phase of the voltage phase that is not in phase is assumed and the phase of the phase that is out of phase is assumed, the phase of the phase of the phase that is out of phase is set to the phase of the voltage of the other phase. And calculating the phase difference between the phase of the voltage calculated by this means and the phase of the current detected in the phase in which the voltage is lost, and the current value is obtained from this phase difference and the instantaneous current value. Means for calculating the effective portion of the current value, and means for measuring the cumulative value of the effective portion of the current value calculated by the means.
[0021]
With such a configuration, it is possible to measure an accumulated value of an effective portion of a current value during an open phase state, ie, an effective integrated current value, for a phase that is open.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, in the following figures, including the figure which shows a prior art example, the same code | symbol shows the same part or a corresponding part.
[0023]
(First embodiment)
First, a watt-hour meter according to the first embodiment of the present invention will be described.
[0024]
FIG. 1 shows the configuration of the first embodiment. In FIG. 1, reference numerals 1 and 2 denote a primary voltage and a primary current input to the watt-hour meter 100, respectively. Reference numerals 3 and 4 denote a voltage input conversion unit that converts the input primary voltage 1 and primary current 2 into a voltage signal and a current signal, respectively, a current input conversion unit, and 5 a power calculation unit (multiplication unit).
[0025]
In this embodiment, an input voltage monitoring unit 9 using a signal value comparison function is provided on the output side of the voltage input conversion unit 3 so that the voltage input value is between an upper limit or a lower limit of a preset normal range value. Monitor whether there is any.
[0026]
Further, a switch circuit 10 is provided on the output side of the power calculation unit 5 to switch the output between the normal clock amount unit 30 which is an original power amount recording unit and the abnormal clock amount unit 40 which is a recording unit in an abnormal state. It can be configured.
[0027]
The normal clock amount unit 30 includes an integration unit 61, a normal power amount recording unit 71, and a normal power amount display unit 81. The abnormal clock amount unit 40 includes an integration unit 62 and an abnormal power amount recording unit. 72 and an abnormal power amount display unit 82.
[0028]
Next, this operation will be described.
[0029]
When the deviation of the voltage signal value from the normal range is detected by the input voltage monitoring unit 9, the switch circuit 10 is switched from the normal clock amount unit 30 to the abnormal clock amount unit 40, and the abnormal clock amount unit 40 is in an abnormal state. Accumulate the amount of power.
[0030]
With these operations, it is possible to clearly record and display the electric energy measurement values in the normal state and the abnormal state. At this time, in the input voltage monitoring unit 9, if the determination is made with respect to the input voltage value and the result is abnormal, record it so that it can be understood (the input voltage value is abnormal). Thus, it is possible to determine the type of the event that is in an abnormal state from the record.
[0031]
As another example of the configuration method of the switch circuit 10, a method is also conceivable in which the amount of electric power is always accumulated in the normal clock amount unit 30 and is also measured in parallel in the abnormal clock amount unit 40 when there is an abnormality. It is done. In this case, the normal clock amount unit 30 records all the measured power amounts, and the abnormal clock amount unit 40 indicates the measured value in the abnormal state. At this time, the former indicates the total measured value, and the value at the normal time can be known by subtracting the latter value from the former value.
[0032]
If the input voltage monitoring unit 9 detects and determines the frequency instead of detecting and determining the input voltage value as described above, a measured value corresponding to the abnormal state of the frequency can be obtained. In this case, an abnormal state is determined by detecting that the frequency exceeds a preset upper limit value or lower limit value.
[0033]
Further, not only a single-phase watt-hour meter but also a multi-phase watt-hour meter can detect and determine the input voltage value or frequency of each phase and obtain a measured value corresponding to the abnormal state.
[0034]
Furthermore, in a polyphase energy meter, the phase difference between each phase of the output obtained from a plurality of voltage input converters is detected, and by detecting this phase difference, it is possible to detect an abnormality related to the phase. A metric value corresponding to the state can be obtained. In this case, an abnormal state is determined by detecting that the phase difference exceeds a preset upper limit value or lower limit value.
[0035]
Note that if the result is abnormal when the frequency or phase difference is determined, record it so that it can be understood (the frequency or phase difference is abnormal). The type of event (whether it is a voltage value abnormality, a frequency abnormality, or a phase difference abnormality) can be determined.
[0036]
As described above, according to this embodiment, it is possible to separate the records of the normal state and the abnormal state, and obtain a power amount measurement value of the normal state with high accuracy. That is, particularly in an abnormal state that may be caused by human intentional or negligence, the power amount measurement value in that state can be recorded separately from the power amount measurement value in the normal state.
[0037]
(Second Embodiment)
Next, a watt-hour meter according to the second embodiment of the present invention will be described.
[0038]
This embodiment is configured to record an integrated current value (a value obtained by multiplying the current value by time) instead of the abnormal power amount when the input voltage monitoring unit detects a voltage value below a certain value. Thus, the state of the current circuit independent of the voltage state can be recorded.
[0039]
The configuration of this embodiment is shown in FIG. In the watt-hour meter 200 shown in the figure, reference numeral 50 denotes an integrated current measuring unit, which includes an integrating unit 63, an integrated current recording unit 73, and an integrated current display unit 83.
[0040]
In this embodiment, when the input voltage monitoring unit 9 that monitors the output of the voltage input conversion unit 3 detects a voltage value equal to or lower than a certain value, an open phase determination output is performed.
[0041]
The output of the current input conversion unit 4 is supplied to the integration unit 63 via the switch circuit 10, where the current is integrated, the integrated current value is recorded by the integrated current recording unit 73, and the integrated current display unit 74.
[0042]
Further, the output of the power calculation unit 5 can stop the accumulation of the power amount to the normal clock amount unit 30 by the switch 10 a of the switch circuit 10.
[0043]
Next, this operation will be described.
[0044]
When the power supply is in a phase loss state, the output of the power calculation unit 5 is cut off by the determination output of the input voltage monitoring unit 9, and the accumulation of the electric energy during the phase loss period is temporarily stopped.
[0045]
At the same time, if the switch 10b from the output side of the current input conversion unit 4 to the integration unit 63 is closed and the current input is a non-zero value, that is, if a current input is detected, the output is integrated and the phase loss period The total amount of current flowing in the integrated current recording unit 73 is recorded.
[0046]
Further, not only a single-phase watt-hour meter but also a multi-phase watt-hour meter can detect and determine an open phase state of each phase and obtain an integrated value of the current that flows during the open phase period. . In this case, when at least one phase is in an open phase state, an integrated value of currents for all phases during the open phase period may be obtained, or the current of only the phase in the open phase state may be obtained. May be obtained.
[0047]
Furthermore, in the above description, the integrated value of the current is obtained when the voltage value is in a phase-open state where the voltage value is equal to or less than a certain value. However, not only in the case of the phase-open state, the upper limit or lower limit of the normal range value is exceeded. An integrated current value may be obtained when an abnormal state of a voltage value, an abnormal state of a frequency, or an abnormal state of a phase difference between phases in the case of multiple phases is detected and determined.
[0048]
In the case of this embodiment as well, as in the case of the first embodiment, it is possible to know the type of event that is in an abnormal state (abnormal phase state, voltage value, frequency, or phase difference is abnormal). As a result of the recording, the type of the event that has become abnormal from the recording (whether it is a phase failure state, a voltage value abnormality, a frequency abnormality, or a phase difference abnormality) Or the like) can be determined.
[0049]
As described above, according to this embodiment, the flow rate of the current can be recorded even when the connection of the circuit for detecting the voltage is not normal.
[0050]
In addition, when a circuit for detecting voltage is intentionally made abnormal and an attempt is made to steal power, the power value stolen can be assumed from the abnormality and the integrated current value in that state.
[0051]
(Third embodiment)
Next, a watt-hour meter according to the third embodiment of the present invention will be described.
[0052]
In this embodiment, a three-phase four-wire watt-hour meter is configured to record an effective integrated current value in addition to an integrated current value during an open phase period.
[0053]
That is, in this embodiment, in the multiphase watt-hour meter, if the voltage of all phases is not an open phase and the phase of the open phase can be assumed from the phase wire rating, the voltage that has become a voltage open phase Calculate the phase of the signal based on the phase of the voltage signal of the other phase, determine the phase difference between the current signal detected in this phase and the phase of the voltage loss phase, and multiply the instantaneous current value by the phase to assume the effective current value A value is calculated, and separately from the current amount not including the phase described in the second embodiment, the cumulative value of the effective current value is also recorded.
[0054]
The configuration of this embodiment is shown in FIG. In the watt-hour meter 300 shown in the figure, 11, 12, and 13 are primary voltages, 21, 22, and 23 are primary currents, 31, 32, and 33 are voltage input conversion units, and 41, 42, and 43 are current input conversion units. is there. Reference numerals 51, 52, and 53 denote power calculation units (multiplication units), and 55 denotes an addition unit. Reference numeral 130 denotes a normal power amount metering unit, which includes an integration unit 131, a normal power amount recording unit 132, and a normal power amount display unit 133.
[0055]
Reference numeral 90 denotes a phase loss determination / phase loss portion phase information generation unit. 101, 102, and 103 are 1-phase open phase determination, 2-phase open phase determination, 3-phase open phase determination, 111, 112, and 123 are 1-phase current value, 2-phase current value, 3-phase current value, 121, 122, Reference numerals 123 denote a one-phase phase calculation value, a two-phase phase calculation value, and a three-phase phase calculation value, respectively.
[0056]
Reference numeral 140 denotes a one-phase integrated current / effective integrated current measuring unit. The switch 141, the integrating unit 142, the integrated current recording unit 143, the integrated current display unit 144, the effective current calculating unit 145, the integrating unit 146, and the effective integrated current recording unit 147. , And an effective integrated current display unit 148.
Reference numerals 150 and 160 denote a two-phase integrated current / effective integrated current measuring unit and a three-phase integrated current / effective integrated current measuring unit, respectively. Has been.
[0057]
Next, this operation will be described.
[0058]
When all three phases are normal, the outputs of the power calculation units (multiplication units) 51, 52, and 53 are added by the addition unit 55 and supplied to the integration unit 131 of the normal power amount measurement unit 130 to accumulate the power amount. Is called.
[0059]
When one of the phases is in an open phase state, the open phase determination / open phase part phase information generation unit 90 detects and determines this. For example, when it is detected and determined that one phase is in an open phase open phase state, the open phase determination / open phase part phase information generation unit 90 causes the one-phase integrated current / effective integrated current measuring unit 140 to The determination 101 is output, and the one-phase phase calculation value 121 calculated from the phases of the other phases is output. In the one-phase integrated current / effective integrated current measuring unit 140, the switch 141 is closed by the one-phase open phase determination 101, the integrated unit 142 obtains the integrated value of the one-phase current value 111, and the effective current calculating unit 145 has 1 An effective current is calculated from the phase current value 111 and the one-phase phase calculation value 121 and supplied to the integration unit 146, and the integration unit 146 obtains an effective integrated current value.
[0060]
As described above, according to this embodiment, the flow rate of the current can be recorded even when the connection of the circuit for detecting the voltage is not normal.
[0061]
In addition, when an attempt is made to intentionally detect a voltage and detect theft of power, the stolen power value can be assumed from the abnormality and the integrated current value or effective integrated current value in that state. .
[0062]
(Other embodiments)
In each of the embodiments described above, a hardware implementation method has been shown as an example. However, in a digital watt-hour meter that quantizes an input signal and digitally performs each internal process, the same applies. Equivalent functions can be realized by digital processing.
[0063]
【The invention's effect】
As described above, according to the present invention, it is possible to determine whether or not a measurement value in an abnormal state is included, and in particular, the amount of power used in an environment where it is necessary to detect and record an abnormal state. It is effective in the total.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a watt-hour meter according to a first embodiment of the present invention.
FIG. 2 is a block diagram showing a configuration of a watt hour meter according to a second embodiment of the present invention.
FIG. 3 is a block diagram showing a configuration of a watt hour meter according to a third embodiment of the present invention.
FIG. 4 is a block diagram showing a configuration of a conventional watt-hour meter.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 100 ... Electricity meter 1 ... Primary voltage 2 ... Primary current 3 ... Voltage input conversion part 4 ... Current input conversion part 5 ... Power calculating part (multiplication part)
DESCRIPTION OF SYMBOLS 9 ... Input voltage monitoring part 10 ... Switch circuit 30 ... Normal clock amount part 40 ... Abnormal clock amount part 61 ... Integration part 71 ... Normal electric energy recording part 81 ... Normal electric energy display part 62 ... Integration part 72 ... Abnormality Electricity amount recording unit 82 ... Abnormal electric energy display unit 200 ... Electricity meter 10a, 10b ... Switch 50 ... Integrated current measuring unit 63 ... Integration unit 73 ... Integrated current recording unit 83 ... Integrated current display unit 300 ... Electricity meter 11 , 12, 13 ... primary voltage 21, 22, 23 ... primary current 31, 32, 33 ... voltage input converter 41, 42, 43 ... current input converter 51, 52, 53 ... power calculator (multiplier)
55 ... Addition unit 90 ... Missing phase determination / missing phase information generation unit 101 ... 1 phase missing phase determination 102 ... 2 phase missing phase determination 103 ... 3 phase missing phase determination 111 ... 1 phase current value 112 ... 2 phase current value 123 ... Three-phase current value 121 ... One-phase phase calculation value 122 ... Two-phase phase calculation value 123 ... Three-phase phase calculation value 130 ... Normal power consumption measuring unit 131 ... Integration unit 132 ... Normal power consumption recording unit 133 ... Normal Hourly power display unit 140 ... one-phase integrated current / effective integrated current measuring unit 141 ... switch 142 ... integration unit 143 ... integrated current recording unit 144 ... integrated current display unit 145 ... active current calculation unit 146 ... integration unit 147 ... effective integration Current recording unit 148 ... Effective integrated current display unit 150 ... Two-phase integrated current / effective integrated current measuring unit 160 ... Three-phase integrated current / effective integrated current measuring unit

Claims (9)

A single-phase or multi-phase energy meter that detects the AC voltage and AC current of the circuit under test, calculates the signals corresponding to them, converts them into signals proportional to the power, and accumulates them to measure the power In the above, a means for determining an abnormal state by detecting that the AC voltage value exceeds a preset upper limit value or lower limit value, and measuring the amount of power during which the AC voltage value is determined to be abnormal by this means And a watt hour meter characterized by comprising: A single-phase or multi-phase energy meter that detects the AC voltage and AC current of the circuit under test, calculates the signals corresponding to them, converts them into signals proportional to the power, and accumulates them to measure the power , Means for determining an abnormal state by detecting that the frequency of the AC voltage exceeds a preset upper limit value or lower limit value, and the amount of electric power during which the means is determined to be in an abnormal state by this means. A watt-hour meter comprising means for measuring. In a multi-phase watt-hour meter that detects the AC voltage and AC current of the circuit under test, calculates the signals corresponding to them, converts them into signals proportional to power, and measures the power by accumulating these signals. Means for determining an abnormal state by detecting that the phase difference of the AC voltage exceeds a preset upper limit value or lower limit value, and the amount of electric power during which the means is determined to be in an abnormal state by this means. A watt-hour meter comprising means for measuring. A single-phase or multi-phase energy meter that detects the AC voltage and AC current of the circuit under test, calculates the signals corresponding to them, converts them into signals proportional to the power, and accumulates them to measure the power , A means for determining an abnormal state by detecting that the AC voltage value exceeds a preset upper limit value or lower limit value, and an integrated current value during which the means is determined to be in an abnormal state by this means. A watt-hour meter comprising means for measuring. A single-phase or multi-phase energy meter that detects the AC voltage and AC current of the circuit under test, calculates the signals corresponding to them, converts them into signals proportional to the power, and accumulates them to measure the power Means for determining an abnormal state by detecting that the frequency of the AC voltage exceeds a preset upper limit value or lower limit value, and an integrated current value during which the means is determined to be in an abnormal state A watt hour meter characterized by comprising: In a multi-phase watt-hour meter that detects the AC voltage and AC current of the circuit under test, calculates the signals corresponding to them, converts them into signals proportional to power, and measures the power by accumulating these signals. Means for determining an abnormal state by detecting that the phase difference of the AC voltage exceeds a preset upper limit value or lower limit value, and an integrated current value during which the abnormal state is determined by this means A watt hour meter characterized by comprising: The watt-hour meter according to any one of claims 1 to 6, further comprising means for recording a type of an event that has become an abnormal state when it is determined that the state is abnormal. Total. A single-phase or multi-phase energy meter that detects the AC voltage and AC current of the circuit under test, calculates the signals corresponding to them, converts them into signals proportional to the power, and accumulates them to measure the power And a means for detecting that the alternating voltage is in a state below a certain value that can be regarded as an open phase, and a means for measuring the integrated current value while the state is detected by this means. A watt hour meter characterized by In a multi-phase watt-hour meter that detects the AC voltage and AC current of the circuit under test, calculates the signals corresponding to them and converts them into signals proportional to power, and accumulates them to measure the power. When the phase voltage is not open and the phase of the open phase can be assumed, the phase of the phase of the phase that is open is calculated from the phase of the voltage of the other phase, and this means Means for calculating a phase difference between the phase of the voltage and the phase of the current detected in the phase in which the voltage is lost, and calculating an effective amount of the current value from the phase difference and the instantaneous current value; A watt-hour meter comprising means for measuring a cumulative value of an effective current value calculated by the means.

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