JP2002174648A - Watt-hour meter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve a watt-hour meter capable of obtaining useful information on reducing electric energy. SOLUTION: The relation between voltage and power can be obtained without particularly changing the voltage of an electric circuit by providing a voltage- power characteristics calculating part 47 for finding the relation between voltage and power from a voltage measured value at a voltage measuring part 41 and a power measured value at a power measuring part 44. In addition, by providing an electric energy simulation part 48 at a specific voltage for calculating the electric energy at a specific voltage in a given period using the relation between voltage and power determined by the voltage-power characteristic calculating part 47, the electric energy when changing the voltage of an alternating current electric circuit 1 to the specific voltage may be known easily. In addition, by providing an electric energy reduction calculation part 49 for determining a difference between the electric energy calculated by the electric energy measuring part 43 and the electric energy calculated by the electric energy simulation part at a specific voltage 48, an effect of the electric energy reduction when changed to the specific voltage may be known easily.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a watt hour meter for measuring an amount of power from the voltage and current of an AC circuit.

[0002]

2. Description of the Related Art FIG. 6 is a block diagram showing the configuration of a conventional watt-hour meter. Reference numeral 1 denotes an AC circuit of an electric circuit to be measured, 2 denotes a current transformer, 3 denotes a load, and 6 denotes a conventional watt-hour meter. . The conventional watt-hour meter 6 includes a voltage measurement unit 41 that captures and measures the voltage of the AC circuit 1, a current measurement unit 42 that captures and measures the current of the AC circuit 1 via the current transformer 2, and a voltage measurement unit 41. And a power amount measuring unit 43 for inputting a measurement value of the current measuring unit 42 to obtain a power amount, a voltage measuring unit 41 and a current measuring unit 42.
And a power measuring unit 44 for inputting the measured values of the above and calculating the power.

[0003]

In the above-mentioned conventional configuration, the electric power metering unit 43 measures the electric energy and the voltage measuring unit 41
, The power is measured by the power measuring unit 44, but no useful information such as the relationship with the voltage was obtained in reducing the amount of power.

An object of the present invention is to provide a watt hour meter capable of obtaining useful information for reducing the amount of power. Furthermore, it is to provide a watt hour meter that can clearly grasp the relationship between the voltage of the electric circuit and the electric power,
It is still another object of the present invention to provide a watt hour meter that also shows the effect of reducing the amount of power due to voltage improvement.

[0005]

According to a first aspect of the present invention, there is provided a watt-hour meter comprising: a voltage measuring unit for continuously measuring a voltage of an electric circuit; a current measuring unit for continuously measuring a current of the electric circuit; A watt hour meter that measures an amount of power based on the voltage measured by the voltage measuring unit and the current measured by the current measuring unit, and divides the range of the measured voltage of the voltage measuring unit into a plurality. And a voltage section for each voltage section for inputting a voltage measurement value continuously measured by the voltage measurement section and calculating a frequency of occurrence of the input voltage measurement value for each voltage section. It is characterized by.

According to a second aspect of the present invention, there is provided a watt-hour meter comprising: a voltage measuring unit for continuously measuring a voltage of an electric circuit; a current measuring unit for continuously measuring a current of the electric circuit; A watt hour meter comprising a power meter and a power meter based on the current value measured by the value and the current measuring unit, wherein the range of the measured voltage of the voltage measuring unit is divided into a plurality of voltage categories, A voltage measurement value continuously measured by the voltage measurement unit is input, and a voltage measurement value only when the load connected to the electric circuit is operated is extracted from the input voltage measurement values. It is characterized in that an occurrence frequency counting section for each voltage section at the time of load for calculating the occurrence frequency for each voltage section is provided.

According to a third aspect of the present invention, there is provided a watt-hour meter comprising: a voltage measuring unit for continuously measuring a voltage of an electric circuit; a current measuring unit for continuously measuring a current of the electric circuit; A power measurement unit that measures power based on the current measurement value by the value and current measurement unit, and a power amount measurement unit that measures the power amount based on the voltage measurement value by the voltage measurement unit and the current measurement value by the current measurement unit. A watt-hour meter with
A voltage-power characteristic calculation unit is provided for obtaining a relationship between voltage and power from a voltage measurement value of the voltage measurement unit measured at the same time and a power measurement value of the power measurement unit.

According to a fourth aspect of the present invention, in the watt hour meter according to the third aspect, the watt hour meter corresponds to the voltage measurement value of the voltage measurement unit and the power measurement value of the power measurement unit measured at the same time. The power at the specific voltage is calculated using the relationship between the voltage and the power obtained by the voltage-power characteristic calculation unit, and the power amount at the specific voltage within a predetermined period is calculated using the calculated value. A power amount simulation unit is provided.

According to a fifth aspect of the present invention, there is provided the watt-hour meter according to the fourth aspect, wherein the watt-hour within the predetermined period calculated by the watt-hour meter and the predetermined period calculated by the watt-hour simulation unit are used. And a power reduction calculator for calculating a difference between the power and the power when a specific voltage is set.

According to a sixth aspect of the present invention, in the watt-hour meter according to the third aspect, an optimum voltage having a maximum efficiency is obtained from a relationship between the voltage and the power obtained by the voltage-power characteristic calculation unit. Calculates the power when the optimum voltage is calculated by the optimum voltage calculator using the relationship between the voltage and the power calculated by the optimal voltage calculator and the voltage-power characteristic calculator, and uses the calculated value for a predetermined period. And a power amount simulation unit for calculating a power amount when the voltage is the optimum voltage.

[0011]

The watt hour meter according to the first aspect of the present invention divides the range of the voltage measured by the voltage measuring unit into a plurality of voltage divisions and continuously measures the voltage by the voltage measuring unit. It is characterized in that an occurrence frequency counting unit for each voltage section for inputting a value and calculating the occurrence frequency of the input voltage measurement value for each voltage section is provided. Since the voltage variation characteristics of the electric circuit can be known by the occurrence frequency counting unit for each voltage section, the electric circuit voltage can be analyzed with respect to the electric energy by the electric energy measuring unit, and useful information for reducing the electric energy can be obtained. It has the effect of being able to.

According to a second aspect of the present invention, in the watt hour meter, the range of the voltage measured by the voltage measuring unit is divided into a plurality of voltage divisions, and a voltage measurement value continuously measured by the voltage measuring unit is inputted. , Extracts voltage measurement values only during operation of the load connected to the electric circuit from the input voltage measurement values, and calculates the frequency of occurrence of the extracted voltage measurement values for each voltage division. A frequency counting unit is provided. Since the voltage variation characteristics of the electric circuit during the load operation can be known by the occurrence frequency counting unit for each voltage division at the time of the load, the electric circuit voltage can be analyzed with respect to the electric energy by the electric energy meter during the load operation, and the electric power can be analyzed. This has the effect that useful information for reducing the amount can be obtained.

According to a third aspect of the present invention, there is provided a watt-hour meter which calculates a voltage-power relationship from a voltage measurement value of a voltage measurement unit measured at the same time and a power measurement value of a power measurement unit.
A power characteristic calculation unit is provided. This voltage-
The provision of the power characteristic calculation unit has an effect that a relationship between voltage and power, which is useful information for reducing the amount of power, can be obtained without particularly changing the voltage of the electric circuit.

According to a fourth aspect of the present invention, in the watt-hour meter according to the third aspect, the watt-hour meter corresponds to the voltage measurement value of the voltage measurement unit and the power measurement value of the power measurement unit measured at the same time. The power at the specific voltage is calculated using the relationship between the voltage and the power obtained by the voltage-power characteristic calculation unit, and the power amount at the specific voltage within a predetermined period is calculated using the calculated value. A power amount simulation unit is provided. The power amount simulation unit has an effect that the power amount when the voltage of the electric circuit is improved to the specific voltage can be easily known by the simulation.

According to a fifth aspect of the present invention, there is provided the watt-hour meter according to the fourth aspect, wherein the watt-hour within the predetermined period calculated by the watt-hour meter and the predetermined period calculated by the watt-hour simulation unit are used. And a power reduction calculator for calculating a difference between the power and the power when a specific voltage is set. This power amount reduction calculator has an effect that the power amount reduction effect when the voltage of the electric circuit is changed to the specific voltage can be easily known.

According to a sixth aspect of the present invention, in the watt-hour meter according to the third aspect, an optimum voltage having a maximum efficiency is obtained from the relationship between the voltage and the power obtained by the voltage-power characteristic calculation section. Calculates the power when the optimum voltage is calculated by the optimum voltage calculator using the relationship between the voltage and the power calculated by the optimal voltage calculator and the voltage-power characteristic calculator, and uses the calculated value for a predetermined period. And a power amount simulation unit for calculating a power amount when the voltage is the optimum voltage. The provision of the optimum voltage calculation unit and the power amount simulation unit has an effect that the power amount when the voltage of the electric circuit is improved to the optimum voltage can be easily known by the simulation.

An embodiment of the present invention will be described below with reference to FIGS.

(First Embodiment) FIG. 1 shows a first embodiment of the present invention.
FIG. 3 is a block diagram showing a watt hour meter according to the embodiment. 1 is an AC circuit of a circuit to be measured, 2 is a current transformer for detecting a current of the AC circuit 1, 3 is a load, and 4 is a watt hour meter of the present embodiment.

The watt hour meter 4 of the present embodiment comprises an AC power line 1
A voltage measuring unit 41 for continuously taking in the voltage of the AC circuit 1, a current measuring unit 42 for continuously taking in the current of the AC circuit 1 via the current transformer 2, and a voltage measuring unit 41 and a current measuring unit 42. An electric energy meter 43 for obtaining electric energy based on the measured value, and an electric power measuring unit 44 for inputting the measured values of the voltage measuring unit 41 and the current measuring unit 42 to obtain electric power are provided. Further, the occurrence frequency counting unit 45 for each voltage section
A load-frequency-specific-occurrence-frequency counting unit 46, a voltage-power characteristic calculation unit 47, a power amount simulation unit 48 at a specific voltage, and a power amount reduction calculation unit 49. Here, it is assumed that the voltage measurement unit 41 samples the input voltage waveform at regular intervals and outputs a sampled value. The current measurement unit 42 samples the input voltage waveform at regular intervals and outputs a sampled value.

The frequency counting unit 45 for each voltage division divides the range of the voltage measured by the voltage measurement unit 41 into a plurality of voltage divisions at appropriate intervals to form a plurality of voltage divisions. By judging which voltage division the value (sampling value) is, and counting the number of voltage measurement values (sampling value) included in each voltage division, each voltage division of the continuously measured voltage measurement value Is calculated, and a voltage division-frequency characteristic as shown in FIG. 2 is obtained. The occurrence frequency counting unit 45 for each voltage section performs a counting operation regardless of whether the load is applied (when the load 3 is operated) or not (when the load 3 is not operated).

A frequency counting unit 4 for each voltage division under load
Reference numeral 6 denotes a plurality of voltage divisions obtained by subdividing the range of the voltage measured by the voltage measurement unit 41 into a plurality of voltage divisions at appropriate intervals, and selecting a voltage measurement value (sampling value) input from the voltage measurement unit 41 during load. Only during the operation of the load 3 is the voltage measurement value extracted, the voltage measurement value (sampling value) extracted is determined to which voltage division, and the number of voltage measurement values included in each voltage division is counted. In this way, the frequency of occurrence of continuously measured voltage measurement values for each voltage section is calculated.
The frequency characteristic is obtained. The frequency counting unit 46 for each voltage division at the time of load inputs the measurement value of the current measurement unit 42 or the power measurement unit 44 (not shown), and the measurement value of the current measurement unit 42 or the power measurement unit 44 becomes zero. In the case of, it is determined that there is no load, and when it is not zero, it is determined that there is load.

The voltage-power characteristic calculation unit 47 includes a voltage measurement unit
41 measured voltage and electric power for continuous measurement of instantaneous electric power
With the power measured value of the measuring unit 44 as input, the circuit voltage fluctuates
By calculating the power at the time of
Multiple characteristics of voltage and power for pressure range
A function y indicating a plurality of voltage-power characteristics such as₁= F ₁
(X), y_Two= F_Two(X) or y_Three= F_Three(X) (y₁,
y_Two, Y_ThreeAre different loads A, B, and C, respectively.
Power, x is voltage) and characteristic curve
It is. These functions and characteristic curves are
From the plot of pressure and power on one plane,
Approximate by connecting adjacent data from the data in contact and the tendency of fluctuation
Voltage-power corresponding to load fluctuation
A characteristic curve is obtained. Also, here, voltage-power
To obtain the characteristic curve, as much data as possible
It takes the required period and can be used in subsequent measurements
Requires the following procedure.

The power amount simulation unit 48 at a specific voltage receives the outputs of the voltage-power characteristic calculation unit 47, the power measurement unit 44, and the voltage measurement unit 41 as inputs, and outputs the instantaneous power measured by the power measurement unit 44; The instantaneous voltage measured by the voltage measurement unit 41 and a plurality of functions y ₁ = f ₁ (x), y ₂ = f ₂ (x), y ₃ = f of the voltage-power characteristic calculation unit 47
₃ (x), the voltage-corrected power at the specific voltage is obtained, and by continuously performing the power, the power amount of the specific voltage for a predetermined period is obtained by simulation. Note that the power amount simulation section 48 at a specific voltage has a specific voltage setting section for setting an arbitrary voltage as the specific voltage.

The power amount reduction calculation unit 49 includes the power amount measurement unit 4
The difference between the power amount within the predetermined period calculated in step 3 and the power amount at the specific voltage within the predetermined period calculated by the power amount simulation unit 48 at the specific voltage is calculated.

In this case, the voltage measuring section 41 and the current measuring section 42 output the sampling values. However, if the voltage or current is measured and output in an analog manner, the output values are output. , A power amount measuring unit 43, a power measuring unit 44, an occurrence frequency counting unit 45 for each voltage division, an occurrence frequency counting unit 46 for each voltage division under load,
In the voltage-power characteristic calculation unit 47 and the power amount simulation unit 48, their input values may be sampled at regular intervals.

The details will be described below. For example, in FIG. 3, when the load A is set and the specific voltage setting unit in the electric energy simulation unit 48 sets V _s to a specific voltage, W _s1
Is the power at a particular voltage V _s , whereas V _a
In measuring the voltage at a certain time is, W _a1 is the measured power at the time measures the measurement voltage V _a, the voltage corrected power at a particular voltage V _s, W _a1 is W _s1 in this example.

There are the following two methods for calculating the electric energy in the electric energy simulation unit 48.

First, the first method will be described with reference to FIG. Measurement of the instantaneous voltage at the voltage measuring unit 41, measures the instantaneous current in the current measurement unit 42, measurement of the instantaneous power by the power measuring unit 44, but the metering of electric energy in the electric energy measuring section 43 is made, the time t ₀ ~t _{During one} time, each time the instantaneous voltage and instantaneous power are measured by the voltage-power characteristic calculation unit 47, the values are stored in a voltage-power table.

Then, between the times t ₁ and t ₂ , the voltage-power characteristic calculating section 47 obtains a voltage-power characteristic curve (or function).

Next, from time t _{2 to} time t ₃ , the power amount simulation section 48 sets the voltage-power characteristic curve every time the instantaneous voltage and the instantaneous power are measured, with the time t _{2 to} t ₃ being a predetermined period. with reference seek power whose voltage has been corrected at a particular voltage, by doing this continuously, the amount of power between the time t ₂ ~t ₃ of when the specific voltage (kWH
2). Incidentally, the specific voltage is a value set at time t ₂ in the amount of power simulation unit 48.

In the first method, the power reduction calculator 4
9 values for determining the time t ₂ watt measuring section 43 between ~t ₃
Let kWH1 be the amount of power measured by kWH1
−kWH2.

Next, the second method will be described with reference to FIG. Similarly, the voltage measurement unit 41 measures the instantaneous voltage, the current measurement unit 42 measures the instantaneous current, and the power measurement unit 44
In measuring instantaneous power, but weighed amount of power in the electric energy measuring section 43 is made, between the time t ₀ ~t _1, each time the instantaneous voltage and instantaneous power measurement, continuously power them at paired data Each time the instantaneous voltage and the instantaneous power are measured, the values are stored in the voltage-power table in the voltage-power characteristic calculating section 47.

Then, between the times t ₁ and t ₂ , the voltage-power characteristic calculating section 47 obtains a voltage-power characteristic curve (or function).

Next, at time t_Two~ T_FourBetween the electricity
The simulation unit 48 calculates the time t ₀~ T₁Predetermined period
As the interval, based on the pair data stored continuously, the voltage
− Voltage compensation at a specific voltage with reference to the power characteristic curve
Find corrected power and perform this continuously to identify
Time t as voltage₁~ T_Two(KWH3)
).

In the second method, the electric energy reduction calculator 4
The value obtained in step 9 is determined by the electric energy meter 43 between the times t _{0 and} t _1.
Let kWH0 be the power amount measured by kWH0.
−kWH3. That is, in the second method, since the simulation is performed based on the pair data after the measurement, the specific voltage can be changed and the simulation can be performed any number of times.
A larger memory capacity is required than in the first method.

The function and operation of each part of the above configuration will be described in detail below. In general, a plurality of various loads are connected to the AC power line, and therefore, the power supply voltage of the system fluctuates more toward the end depending on the operation state of the load. On the other hand, it is known that the amount of power varies depending on the circuit voltage even with the same load.
It is desirable to make the circuit voltage the optimum voltage as a power saving measure. However, it has been difficult to improve the circuit voltage to the optimum voltage without grasping the actual state of the instantaneous fluctuation of the circuit voltage such as flicker.

On the other hand, in the present embodiment, the occurrence frequency counting section 45 for each voltage section is provided, and the frequency of occurrence of the voltage measurement value measured by the voltage measurement section 42 for each voltage section is calculated. Since the voltage fluctuation characteristics can be known, it is possible to analyze the electric circuit voltage with respect to the electric energy by the electric energy measuring unit 43, and to obtain useful information for reducing the electric energy. For example, if it is found that the range of the voltage fluctuation characteristic is narrow and the maximum frequency voltage is higher than the rated value of the load to be used, it is possible to reduce the voltage of the electric circuit and use it. In a simple load, the lower the voltage is, the lower the power consumption of the load is. Here, since the working voltage range is defined for the device serving as the load, it is necessary to know that the device is used within the guaranteed range. Therefore, the voltage fluctuation characteristic is used. As one method of lowering the voltage, it is common to change the tap voltage of a transformer that supplies a voltage to an electric circuit.

Further, an occurrence frequency counting section 46 for each voltage section at the time of load is provided, and the frequency of occurrence of the voltage measurement value measured by the voltage measurement section 42 at the time of load operation for each voltage section is calculated. Since the voltage fluctuation characteristics during the load operation can be known, the electric circuit voltage can be analyzed with respect to the electric energy by the electric energy metering unit 43 during the load operation, and useful information for reducing the electric energy can be obtained. it can. Since the voltage-frequency occurrence frequency counting section 46 at the time of load can know the voltage fluctuation characteristics only at the time of load operation, the voltage-frequency occurrence frequency counting section 46 has higher accuracy than the voltage-frequency occurrence frequency counting section 45 as information for reducing the amount of power. The circuit voltage can be analyzed.

Therefore, even if only one of the voltage division occurrence frequency counting section 45 and the load voltage division occurrence frequency counting section 46 is provided, it is possible to obtain useful information for reducing the amount of power. However, the occurrence frequency counting section 46 for each voltage division at the time of load provides more useful information. In the present embodiment, since both are provided, comparing the two data has the following effects. If the magnitude of the voltage fluctuation is during load operation, it is affected by both the load before and after the measurement point,
On the other hand, the voltage fluctuation at the time of no load is due to the influence of only the load before the measurement point. Therefore, when the voltage fluctuation at the time of no load is small and the voltage fluctuation at the time of the load operation is large, it is understood that the voltage fluctuates due to the line resistance to the load, and the size of the electric wire up to the load is improved. As a result, voltage fluctuation can be reduced, and there is an effect that load characteristics are stabilized by power loss and voltage improvement on the line.

Next, when the load 3 is a fixed load, even if it is desired to know an efficient circuit voltage, it is necessary to actually vary the circuit voltage and to investigate it. Is generally not provided, which is very difficult.

On the other hand, in the present embodiment, a voltage-power characteristic calculating section 47 is provided, whereby the voltage and current at that time are checked for a certain period every time the circuit voltage fluctuates.
Since it is possible to know the voltage-power characteristic with respect to the range of the voltage fluctuation, information (voltage-power) useful for reducing the power amount while measuring the power amount without changing the voltage of the AC circuit 1 in particular. Characteristics) can be obtained.

Further, by providing the power amount simulation section 48 at a specific voltage, the power amount when the circuit voltage is improved to the specific voltage can be easily known by simulation. However, in this case, it is necessary to first determine the voltage-power characteristics within a certain period and then simulate the power amount.

Further, a power amount reduction calculating unit 49 is provided, and the power amount within the predetermined period calculated by the power amount measuring unit 43 and the specific voltage within the predetermined period calculated by the power amount simulation unit 48 at the specific voltage are provided. By obtaining the difference from the power amount at the time of performing, it is possible to easily know the effect of reducing the power amount by improving to the specific voltage.

(Second Embodiment) FIG. 5 shows a second embodiment of the present invention.
FIG. 5 is a block diagram showing a configuration of the watt hour meter according to the embodiment.
Is a watt hour meter of the present embodiment. The same parts as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

The optimum voltage calculating section 51 obtains the optimum voltage having the maximum efficiency from the voltage-power characteristics obtained by the voltage-power characteristic calculating section 47. For example, in FIG. 3, V ₀ is a voltage having the highest operation efficiency, which is set as an optimum voltage, and operating at this voltage leads to a minimum power consumption. The power amount simulation unit 52 at the optimum voltage is the same as the power amount simulation unit 48 at the specific voltage in the first embodiment (using the optimum voltage instead of the specific voltage), and the optimum voltage calculated by the optimum voltage calculation unit 51 is used. Is obtained by simulation. At this time, FIG.
In any of the first and second methods shown in (a) and (b), the voltage-power characteristic calculator 47 obtains the voltage-power characteristic between the times t _{1 and} t ₂ , and obtains the characteristic. The optimum voltage calculator 51 extracts the optimum voltage from the above.

According to the present embodiment, it is possible to obtain the amount of power in the case of the optimum voltage with the voltage of the AC circuit 1 as the maximum efficiency. This is compared with the actually measured power amount obtained by the power amount measurement unit 43, and the difference between the two is obtained, so that the effect of reducing the power amount by improving to the optimum voltage can be known. That is, the power amount reduction calculation unit 49 calculates the power amount within the predetermined period calculated by the power amount measurement unit 43 and the power amount when the optimum voltage within the predetermined period calculated by the power amount simulation unit 52 is obtained. By obtaining the difference, the effect of reducing the amount of power by improving the voltage can be easily known.

In the first embodiment, the optimum voltage (eg, V _{0 in} FIG. 3) is set as the specific voltage by the specific voltage setting section in the electric energy simulation section 48, thereby improving the optimum voltage. By doing so, the effect of reducing the amount of power can be easily known.

In the first embodiment, the voltage-
An optimum voltage calculator 51 that receives an output of the power characteristic calculator 47 and outputs an optimum voltage to the power amount simulator 48.
May be added so that the power amount simulation unit 48 can switch and use the specific voltage set by the internal specific voltage setting unit and the optimum voltage calculated by the optimum voltage calculation unit 51.

[0049]

According to the watt hour meter according to the first aspect of the present invention, since the occurrence frequency counting section for each voltage section is provided, the voltage fluctuation characteristics of the electric circuit can be known. The circuit voltage can be analyzed for the electric energy,
Information that is useful in reducing the amount of power can be obtained.

According to the watt hour meter according to the second aspect of the present invention, since the occurrence frequency counting unit for each voltage division at the time of load is provided, the voltage fluctuation characteristics of the electric circuit at the time of load operation can be known. The electric circuit voltage can be analyzed with respect to the electric energy by the electric energy meter during the load operation, and useful information for reducing the electric energy can be obtained.

According to the watt hour meter according to the third aspect of the present invention, since the voltage-power characteristic calculating section is provided, information useful for reducing the amount of power without changing the voltage of the electric circuit. The relationship between voltage and power can be obtained.

According to the watt hour meter according to the fourth aspect of the present invention, the watt hour meter according to the third aspect further includes a power amount simulation unit, so that the voltage of the electric circuit can be improved to a specific voltage. The amount of power can be easily known by simulation.

According to the watt hour meter according to the fifth aspect of the present invention, the power meter according to the fourth aspect further includes a power amount reduction calculating unit, so that the voltage of the electric circuit is changed to a specific voltage. Power consumption reduction effect can be easily known.

According to the watt hour meter of the present invention, the watt hour meter of the third aspect is further provided with an optimum voltage calculating section and a power amount simulating section so that the voltage of the electric circuit can be maximized. The amount of power when the voltage is improved to the optimum voltage can be easily known by simulation.

[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 voltage section-frequency characteristic diagram by a voltage section-based occurrence frequency counting section or a voltage section-based occurrence frequency counting section under load in the first embodiment of the present invention.

FIG. 3 is a voltage-power characteristic diagram by a voltage-power characteristic calculation unit according to the first embodiment of the present invention.

FIG. 4 is a view for explaining a method of obtaining a power amount by simulation according to the first embodiment of the present invention.

FIG. 5 is a block diagram illustrating a configuration of a watt hour meter according to a second embodiment of the present invention.

FIG. 6 is a block diagram showing a configuration of a conventional watt hour meter.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 AC electric circuit 2 Current transformer 3 Load 4 Watt hour meter 41 of the first embodiment of the present invention 41 Voltage measuring unit 42 Current measuring unit 43 Power amount measuring unit 44 Power measuring unit 45 Voltage frequency generation frequency counting unit 46 Load Occurrence frequency counting unit for each voltage division at the time 47 Voltage-power characteristic calculation unit 48 Power amount simulation unit at specific voltage 49 Power amount reduction calculation unit 5 Watt hour meter 51 of the second embodiment of the present invention 51 Optimal voltage calculation unit 52 Energy simulation unit at optimal voltage

Claims (6)

[Claims] 1. A voltage measuring unit for continuously measuring a voltage of a circuit, a current measuring unit for continuously measuring a current of the circuit, a voltage measured by the voltage measuring unit and a current measurement by the current measuring unit. A watt hour meter that measures the amount of power based on the value, wherein the range of the measured voltage of the voltage measurement unit is divided into a plurality of voltage divisions, and the voltage measurement unit continuously A watt hour meter, wherein a voltage measurement value to be measured is input, and an occurrence frequency counting unit for each voltage section is provided which calculates an occurrence frequency of the input voltage measurement value for each voltage section. 2. A voltage measuring unit for continuously measuring a voltage of a circuit, a current measuring unit for continuously measuring a current of the circuit, a voltage measured by the voltage measuring unit, and a current measurement by the current measuring unit. A watt hour meter that measures the amount of power based on the value, wherein the range of the measured voltage of the voltage measurement unit is divided into a plurality of voltage divisions, and the voltage measurement unit continuously The voltage measurement value to be measured is input, and the voltage measurement value only when the load connected to the electric circuit is operated is extracted from the input voltage measurement value, and the extracted voltage measurement value is generated for each voltage category. A watt hour meter provided with an occurrence frequency counting unit for each voltage division at the time of load for calculating a frequency. 3. A voltage measuring unit for continuously measuring a voltage of a circuit, a current measuring unit for continuously measuring a current of the circuit, a voltage measured by the voltage measuring unit, and a current measurement by the current measuring unit. A power measuring unit that measures power based on a value, and a watt hour meter that includes a power measuring unit that measures power based on a voltage measured by the voltage measuring unit and a current measured by the current measuring unit. A voltage-power characteristic calculation unit that obtains a relationship between voltage and power from a voltage measurement value of the voltage measurement unit measured at the same time and a power measurement value of the power measurement unit. Watt hour meter. 4. A specific voltage using a relationship between the voltage and the power obtained by the voltage-power characteristic calculation unit corresponding to the voltage measurement value of the voltage measurement unit measured at the same time and the power measurement value of the power measurement unit. 4. The watt hour meter according to claim 3, further comprising: a power amount simulation unit that calculates the power when the specified voltage is obtained within a predetermined period by using the calculated value. . 5. A power amount reduction calculation unit for calculating a difference between the power amount within a predetermined period calculated by the power amount measurement unit and the power amount calculated as a specific voltage within the predetermined period calculated by the power amount simulation unit. 5. The watt hour meter according to claim 4, wherein: 6. An optimum voltage calculating section for obtaining an optimum voltage having a maximum efficiency from a relationship between the voltage and the power obtained by the voltage-power characteristic calculating section, and a voltage and power obtained by the voltage-power characteristic calculating section. A power amount simulation unit that calculates the power when the optimum voltage is obtained by the optimum voltage calculation unit using the relationship, and calculates the power amount when the optimum voltage is obtained within a predetermined period by using the calculated value. The watt hour meter according to claim 3, wherein the watt hour meter is provided.