JP4615046B2 - Electronic energy meter - Google Patents

Description

  The present invention relates to a multi-functional electronic watt-hour meter that can also store voltage values and current values, detect abnormal voltages, and the like.

  FIG. 2 is a block diagram showing an internal configuration of a conventional general electronic watt-hour meter. In FIG. 2, P1 to P3 are probes for detecting an AC voltage value supplied to the internal electric wires L1 to L3 connected to a lead-in wire coming out of a transformer such as a utility pole, and 1 is an impact noise from outside, a surge voltage, etc. 2 is a voltage dividing circuit for generating the polarity of the voltage detected at P1 and P3, CT1 and CT2 are current transformers for detecting the amount of current passing through L1 and L3, and 3 is a voltage dividing circuit. 2 is a power calculation circuit that calculates the power consumption based on the output voltage from 2 and the detected current values from CT1 and CT2, 4 is a CPU that controls each circuit, 5 is an EEPROM that stores the calculated power consumption, etc. A non-volatile memory, 6 is a display unit that displays the calculated power consumption, and 7 is a power supply circuit that generates an internal power supply from the supplied AC voltage and supplies it to each circuit.

  In the electronic watt-hour meter having the above-described configuration, the detected voltage value and current value are multiplied to obtain the amount of power for a predetermined time, and these are integrated to calculate the amount of power used. Data relating to the calculated power consumption is temporarily stored in the nonvolatile memory 5, read out in a predetermined cycle by the CPU 4, and displayed on the display unit 6.

  The conventional electronic watt-hour meter described above only measures and displays the amount of electric power used. However, consumers who install the watt-hour meter are required to manage the voltage and current at the receiving point. There are many requests for information on fluctuations in RMS values.

  In addition, since the conventional electronic watt hour meter does not have means for detecting abnormal voltage or storing such a situation, when trouble such as instrument damage caused by abnormal voltage application occurs, There was a problem that the factor analysis was difficult.

An object of the present invention is to provide a detection and Ru electronic type power meter can store data about the status of the abnormal voltage.

The electronic watt-hour meter according to the present invention is a non-volatile memory that stores power calculation means for calculating the amount of power used based on the detected AC voltage and AC current, and data relating to the power amount calculated by the power calculation means. In an electronic watt-hour meter including a memory, a DC voltage is generated from the detected AC voltage, and the DC voltage is an abnormal voltage based on a comparison result between the DC voltage and a predetermined voltage value set in advance. determining whether, when it is determined that the abnormal voltage is detection time, the DC voltage value and abnormal writes abnormality detection data consisting of three items were duration in the nonvolatile memory abnormal voltage detection It has a recording means.

  According to the electronic watt-hour meter having the above configuration, a circuit for generating a DC voltage from the detected AC voltage is provided, and by comparing the generated DC voltage value with a predetermined voltage value set in advance, the abnormal voltage Perform detection. Specifically, for example, the maximum voltage value of the applied voltage that can be allowed is set as the predetermined voltage value, and it is determined that an abnormal voltage is detected when the generated DC voltage value exceeds this value. When an abnormal voltage is detected, for example, data including a detection date and time, a detected (DC) voltage value, a time during which the abnormality has continued (hereinafter referred to as “abnormality detection data”), and the like are generated. Write to memory.

  Similar to the case of the additional information data, the abnormality detection data can be taken out by communication means provided separately (infrared communication with a handy terminal, data communication using an optical communication line, etc.).

The electronic watt-hour meter of the present invention has a function of detecting abnormal voltage, and when abnormal voltage is detected, data relating to the situation can be saved, so that when a meter trouble occurs due to application of abnormal voltage, etc. By extracting and analyzing such data, it becomes possible to make it easier to clarify the cause.

  Hereinafter, an embodiment of an electronic watt-hour meter according to the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram showing an internal configuration of the electronic watt-hour meter according to the present embodiment. In FIG. 2, the same reference numerals are given to the same parts as the internal configuration (FIG. 2) of the conventional electronic wattmeter.

  As shown in FIG. 1, in addition to the conventional configuration (FIG. 2), the electronic watt-hour meter according to this embodiment has a new configuration in which voltage value and current value data are output from the power calculation circuit to the CPU. In addition, an abnormal voltage detection circuit 30 is newly added. The electronic watt-hour meter according to the present embodiment is provided with new functions (additional information data recording function and abnormality detection data recording function) that are not found in the conventional electronic watt-hour meter due to these newly added configurations. It has characteristics.

[Additional information data recording function]
First, the additional information data (data regarding the detected AC voltage and AC current) recording function will be described. In this embodiment, the CPU 20 constitutes measurement data recording means. CPU20 outputs the signal which requests | requires the data (additional information data) regarding a detection voltage and an electric current with respect to the electric power arithmetic circuit 10 for every fixed period (for example, cycle for every 30 minutes). Upon receiving this, the power calculation circuit 10 receives the data on the detected voltage and current used in the processing at that time (calculation processing of the amount of power used) (in this embodiment, the effective voltage detected at P1 and P3). Value and effective value data of the passing current detected by CT1 and CT2).

  Upon receiving this, the CPU 20 writes the additional information data in the nonvolatile memory 5. More specifically, the non-volatile memory 5 is prepared in advance with a memory area having a predetermined area range for recording additional information data. The CPU 20 writes additional information data in order from the top of this area. Note that when the area becomes full (a state in which there is no free space for newly recording additional information data), a method of overwriting the recorded data in the oldest order (cyclical update) is adopted.

  The additional information data written in the nonvolatile memory 5 can be taken out by communication means (not shown). In this case, specifically, data transfer by infrared communication performed with a data collection terminal (handy terminal) used at the time of meter reading, data transfer using an optical communication line, or the like can be assumed.

[Abnormality detection data recording function]
Next, the data recording function relating to the detection of abnormal voltage and its situation will be described. In the present embodiment, the CPU 20 and the abnormal voltage detection circuit 30 constitute an abnormal voltage detection recording unit. The electronic watt-hour meter according to the present embodiment has an internal circuit configuration in which the AC voltage detected at P1 to P3 is input to the power calculation circuit 10 via the protection circuit 1 and the voltage dividing circuit 2. A line that is input to the abnormal voltage detection circuit 30 through the protection circuit 1 is provided.

  The abnormal voltage detection circuit 30 includes a voltage dividing circuit 31, a P1 rectification / smoothing circuit 32, and a P3 rectification / smoothing circuit 33 therein, and P1 to P3 detection (alternating current) voltages output from the protection circuit 1. To generate DC voltages P1 and P3.

  The CPU 20 inputs the DC voltages of P1 and P3 generated by the abnormal voltage detection circuit 30 and converts them numerically by the built-in A / D converter, and this value (DC voltage value) is an abnormal voltage. It is determined whether it is a value. The determination of whether or not the voltage is abnormal is compared with a maximum allowable voltage value of a preset applied voltage, and when the generated DC voltage value exceeds this value, it is considered that an abnormal voltage has been detected.

  When detecting an abnormal voltage, the CPU 20 generates abnormality detection data. The abnormality detection data is data composed of three items: a detection date and time, a DC voltage value, and a time when the abnormality has continued. Then, the generated abnormality detection data is written into the nonvolatile memory 5. More specifically, as in the case of recording the additional information data described above, the nonvolatile memory 5 is provided with a memory area having a predetermined area range for recording the abnormality detection data in advance. Additional information data is written in order from the top of the area. As in the case of recording additional information data, when the area becomes full, the data is overwritten in the oldest order of the recorded data.

  As in the case of the additional information data described above, the abnormality detection data written in the non-volatile memory 5 is transferred by data transfer (not shown) using communication means (not shown) using infrared communication or an optical communication line. Data transfer etc.).

  The electronic watt-hour meter according to the present invention is not limited to the above embodiment, and various modifications can be made without departing from the gist of the present invention.

  For example, in the above embodiment, the additional information data stored in the nonvolatile memory is the effective value data of the voltage detected by P1 and P3 and the effective value data of the passing current detected by CT1 and CT2, but is not limited thereto. However, as long as it can be generated based on data that can be acquired from the power calculation circuit, any content may be used according to the needs of consumers.

  In the above embodiment, an EEPROM is used as the non-volatile memory, but a flash memory may be employed.

It is a block diagram which shows the internal structure of the electronic watt-hour meter which concerns on one Embodiment of this invention. It is a block diagram which shows the internal structure of the conventional electronic watt-hour meter.

Explanation of symbols

1 protection circuit 2, 31 voltage dividing circuit 3, 10 power calculation circuit 4, 20 CPU
5 Nonvolatile Memory 6 Display Unit 7 Power Supply Circuit 30 Abnormal Voltage Detection Circuit 32 P1 Rectification / Smoothing Circuit 33 P3 Rectification / Smoothing Circuits L1-L3 Internal Wires CT1, CT2 Current Transformers P1-P3 Probe

Claims (1)

In an electronic watt-hour meter comprising: power calculating means for calculating the amount of power used based on the detected AC voltage and AC current; and a nonvolatile memory for storing data relating to the amount of power calculated by the power calculating means ,
A DC voltage is generated from the detected AC voltage, and whether or not the DC voltage is an abnormal voltage is determined based on a comparison result between the DC voltage and a predetermined voltage value set in advance. and if it is determined, the detection date, electronic power and having an abnormal voltage detecting recording means for writing abnormality detection data consisting of three items of time the DC voltage value and abnormality has continued in the nonvolatile memory Quantity meter.

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