Power measurement device and power measurement method

Abstract

A power measurement device according to one aspect of the present disclosure is connected to a power line and comprises: a reading unit that detachably loads a recording medium and reads predetermined setting information recorded on the recording medium; and a communication unit that receives provision request information from a monitoring device and transmits, to the monitoring device, response information including dummy data simulating a measurement value including at least one of a current value and a voltage value of the power line in response to the provision request information.

Description

Power Measurement Device and Power Measurement Method

[0001] The present disclosure relates to a power measurement device and a power measurement method.

[0002] In order to monitor the power consumption of electrical equipment and the like, a power measurement device is provided for each piece of equipment. Patent Document 1 discloses a technique for setting the station number of its own power measurement device by performing serial communication with another power meter via a network.

[0003] Japanese Unexamined Patent Application Publication No. 2016-005418

[0004] When installing a power measurement device, initial settings used for communication tests, operation tests, etc. are performed on the device. When a plurality of power measurement devices are installed, the same settings are made for these devices. It is desirable that the initial settings cover not only the station number of the device but also all necessary settings as in the technique disclosed in Patent Document 1. When manually performing the necessary initial settings for a plurality of power measurement devices one by one, there is a problem that the man-hours involved in the settings increase. ...

[0005] The present disclosure provides a power measurement device capable of reducing the man-hours for initial settings.

[0006] A power measurement device according to an aspect of the present disclosure is a power measurement device connected to a power line, comprising: a reading unit configured to removably load a recording medium and read predetermined setting information recorded on the recording medium; and a communication unit configured to receive provision request information from a monitoring device and transmit response information including dummy data simulating a measurement value including at least one of a current value and a voltage value of the power line with respect to the provision request information to the monitoring device.

[0007] According to the power measurement device according to the present disclosure, the man-hours for initial settings can be reduced.

[0008] Figure 1 is a configuration diagram of a power supply system according to one embodiment of the present disclosure. Figure 2 is a functional block diagram showing the configuration of a power measuring device according to one embodiment of the present disclosure. Figure 3 is a diagram showing an example of predetermined setting information in a power measuring device according to one embodiment of the present disclosure. Figure 4 is a diagram showing an example of time-series change of measured values ​​in a power measuring device according to one embodiment of the present disclosure. Figure 5 is a sequence diagram for explaining a power measurement method according to one embodiment of the present disclosure.

[0009] The embodiments for carrying out the invention will be described below with reference to the drawings. In each drawing, the same reference numerals are used for identical components, and redundant explanations may be omitted.

[0010] [Embodiment] <Configuration of Power Supply System 1> Figure 1 is a configuration diagram of a power supply system 1 according to one embodiment of the present disclosure. The power supply system 1 includes a power source 2, a load 3, a power measuring device 10, and a monitoring device 20. The load 3 is included in work equipment 30 of a factory or the like that performs a predetermined work process. In addition, the power supply system 1 may include multiple power measuring devices 10, loads 3, and work equipment 30, and the number of loads 3 per work equipment 30 may be multiple.

[0011] The work equipment 30 is equipment installed in a factory or the like where products are manufactured and processed, and is equipped with a load 3 that operates using electricity supplied from a power source 2. The predetermined work process is a process in the manufacturing and processing of products, and is a process that is performed using the load 3. The predetermined work process is not limited to, for example, a process of cutting a key with an electric motor when processing an object to be processed such as a key.

[0012] Power source 2 is a power generation facility, etc., for transmitting commercial AC power. Power generation facilities are, for example, facilities of power generation operators such as thermal power generation facilities, solar power generation facilities, and wind power generation facilities. Power source 2 may transmit three-phase AC power consisting of U-phase, V-phase, and W-phase, or it may transmit single-phase AC power. In this embodiment, power source 2 will be described as one that transmits three-phase AC power.

[0013] Hereinafter, the U-phase current flowing from power source 2 through power line 4a to load 3 will be referred to as the "U-phase load current." The V-phase current flowing from power source 2 through power line 4b to load 3 will be referred to as the "V-phase load current." The W-phase current flowing from power source 2 through power line 4c to load 3 will be referred to as the "W-phase load current." Furthermore, the U-phase load current, V-phase load current, and W-phase load current are collectively referred to as the "load current."

[0014] Load 3 is a device used in factory or other work equipment 30 and operates using load current supplied from power supply 2. Load 3 may be, for example, an electric motor used to drive processing equipment such as a cutter for processing objects such as keys. The type of load 3 is not limited to this, and may also be a tool for welding and soldering, an electric drill, an electric screwdriver, a sawing machine, etc.

[0015] The power measuring device 10 is installed in factories and other facilities for purposes such as calculating power consumption. By being connected to power lines 4a, 4b, and 4c, the power measuring device 10 can measure the current and voltage of power lines 4a, 4b, and 4c. The power measuring device 10 is connected between the power source 2 and the load 3.

[0016] Current transformer (CT) 5a detects the U-phase load current flowing through power line 4a. Current transformer 5b detects the W-phase load current flowing through power line 4c. Based on the detection signals detected by current transformers 5a and 5b, the power measuring device 10 measures the current values ​​of the U-phase and W-phase load currents flowing from power source 2 to load 3.

[0017] Voltage transformers (VTs) 6a and 6b are connected to power lines 4a, 4b, and 4c. Voltage transformer 6a is connected between power line 4a, which carries the U-phase load current, and power line 4b, which carries the V-phase load current, and measures the line voltage between U and V. Voltage transformer 6b is connected between power line 4b, which carries the V-phase load current, and power line 4c, which carries the W-phase load current, and measures the line voltage between V and W.

[0018] The power measuring device 10 includes, for example, an integrating circuit that integrates the detection signals detected by the current transformers 5a and 5b, and an amplification circuit that amplifies the signal integrated by the integrating circuit. However, the configuration of the power measuring device 10 is not limited to this.

[0019] Furthermore, the power measuring device 10 measures the current and voltage values ​​of the load 3 and calculates the power consumption, power factor, and frequency of the load 3 based on the measured current and voltage values. The power measuring device 10 transmits the measured current and voltage values, as well as the calculated power consumption and other information, to the monitoring device 20, which is a higher-level device, as response information to the information request information obtained from the monitoring device 20. The response information includes the current and voltage values ​​and power consumption information measured by the power measuring device 10, as well as dummy data for these values.

[0020] As described later, the power measuring device 10 may transmit dummy data, which simulates a measured value including at least one of the current and voltage values ​​of the power lines 4a, 4b, and 4c, to the monitoring device 20 as response information. The power measuring device 10 may be provided with an operable button, and whether or not to transmit dummy data may be set by operating the button.

[0021] The power measuring device 10 and the monitoring device 20 are connected via a communication channel 7a. The power measuring device 10 and the work equipment 30 are connected via a communication channel 7b. The communication channels 7a and 7b may be wireless communication channels or wired communication channels. Examples of communication channels 7a and 7b include Ethernet, RS-485, Wi-Fi (registered trademark), etc.

[0022] The monitoring device 20 monitors the power consumption of the load 3 and the status of the connections of the power lines 4a, 4b, and 4c in the power supply system 1 based on the information received from the power measuring device 10. The status of the connections of the power lines 4a, 4b, and 4c in the power supply system 1 refers to, for example, the on / off status of a Molded Case Circuit Breaker (MCCB) (not shown) and the status of the screw wiring of the MCCB cable.

[0023] Furthermore, the monitoring device 20 can determine the connection status and validity of the measured values ​​of each power line 4a, 4b, and 4c of the multiple power measuring devices 10 by acquiring measured values ​​such as current values, voltage values, and power consumption from the multiple power measuring devices 10. Based on the measured values ​​acquired from the power measuring devices 10, the monitoring device 20 can determine any abnormality in the work equipment 30. If the monitoring device 20 determines that there is an abnormality in the work equipment 30, it can notify the monitoring device 20 of the abnormality.

[0024] <Configuration of Power Measurement Device 10> Figure 2 is a functional block diagram showing the configuration of a power measurement device 10 according to one embodiment of the present disclosure. The power measurement device 10 can perform various settings within the device by reading information recorded on the recording medium 11. The power measurement device 10 comprises a reading unit 12, a communication unit 13, a determination unit 14, and a calculation unit 15.

[0025] The recording medium 11 is a medium that can be attached to and detached from the power measuring device 10. The recording medium 11 is, for example, an SD card. Various data such as dummy data that simulates measured values ​​including at least one of the current and voltage values ​​of power lines 4a, 4b, and 4c, predetermined setting information, and information processing programs are recorded on the recording medium 11. The predetermined setting information includes various information such as items related to alarms corresponding to the measured values, communication protocols with other devices, and initial settings such as time settings.

[0026] The dummy data and predetermined setting information recorded on the recording medium 11 are included in a file that is created in advance so that it can be copied by another device. The power measuring device 10 can read the file containing the predetermined setting information from the recording medium 11 and automatically perform initial settings based on the contents of the read file.

[0027] The reading unit 12 loads the recording medium 11 in a removable manner and reads predetermined setting information recorded on the recording medium 11. When the power measuring device 10 is powered on, the reading unit 12 detects that the recording medium 11 is loaded and reads the predetermined setting information recorded on the recording medium 11.

[0028] The communication unit 13 communicates with the monitoring device 20 and the work equipment 30, which are higher-level devices. The communication unit 13 receives information requesting information from the monitoring device 20 and sends response information to the monitoring device 20 that includes dummy data simulating measured values, which include at least one of the current and voltage values ​​of the power lines 4a, 4b, and 4c, in response to the information requesting information.

[0029] Furthermore, the communication unit 13 determines whether or not to transmit response information to the information request received from the monitoring device 20, and whether or not to enable communication between the power measuring device 10 and the monitoring device 20. The communication unit 13 communicates with the power measuring device 10 and the work equipment 30 and receives a trigger signal from the work equipment 30 to start a predetermined work process.

[0030] The determination unit 14 determines whether or not there is an abnormality based on the measured value and a predetermined threshold value for the measured value. More specifically, the determination unit 14 may determine whether or not there is an abnormality based on the time-series change of the measured value and a predetermined threshold value for the measured value. If there is an abnormality in the work equipment 30, the measured values ​​such as the current value of the load 3 included in the work equipment 30, measured by the power measuring device 10, are often different from normal values.

[0031] Therefore, the determination unit 14 may determine that there is an abnormality in the work equipment 30, for example, when the measured current value is greater than a predetermined threshold value. If the determination unit 14 determines that there is an abnormality in the work equipment 30, the power measuring device 10 may notify the user of the abnormality by sound and by lighting up an LED (light-emitting diode).

[0032] The calculation unit 15 receives a trigger signal transmitted from the work equipment 30 that performs the predetermined work process when the predetermined work process is started, and starts calculating the amount of power consumed in the load 3 during the predetermined work process to calculate the integrated value of the power.

[0033] The calculated cumulative energy consumption may be recorded on the recording medium 11. Furthermore, the recording of the cumulative energy consumption on the recording medium 11 may be performed during a predetermined time period. This allows for a comparison of daily energy consumption changes within the same time period, and enables the correlation between energy consumption and process content at the work process level.

[0034] Here, an example of predetermined setting information recorded on the recording medium 11 will be described. Figure 3 is a diagram showing an example of predetermined setting information in a power measuring device 10 according to one embodiment of the present disclosure. The predetermined setting information includes items related to communication (T1 in the figure), items related to measurement (T2 in the figure), and items related to alarms (T3 in the figure).

[0035] In the communication-related items, CT and CT ratio are the sensor magnifications for current transformers 5a and 5b. The sensor magnification can be set for each current transformer 5a and 5b. The primary voltage and secondary voltage of VT are the rated voltages for the primary and secondary sides of instrument transformers 6a and 6b, respectively. The fixed power factor is set for each circuit in increments of 0.01. The pulse multiplier is the number of pulses converted for each unit of power consumption.

[0036] The communication protocol may be a standard protocol or a proprietary protocol. The communication station number is a station number set for each power measuring device 10. The transmission speed is the transmission speed between the power measuring device 10 and the monitoring device 20, set within the range of 4.8 to 38.4 kbps. The data length and parity are set as either odd parity or even parity.

[0037] In the measurement-related items, the average time / recording time is the period for recording the measured values ​​on the recording medium 11, and is set in minutes. The card recording mode is a setting that determines when the measured values ​​are recorded on the recording medium 11, once a day. The time setting is the setting for the internal clock of the power measuring device 10. The current / voltage demand time, power demand time, and leakage current demand time are the time periods for recording the presence or absence of current, voltage, power, and leakage current, respectively, on the recording medium 11.

[0038] Regarding the alarm section, the output assignment assigns one of the following to each output channel: pulse output, power alarm, current alarm, leakage alarm, momentary voltage sag alarm, and reverse phase alarm, all output from the power measuring device 10. Multiple outputs can be set in the output assignment. For power alarms and current alarms, thresholds for power and current that trigger the alarm are set. For leakage alarms, the threshold for the alarm output is set based on the leakage current value and leakage time.

[0039] The reverse-phase alarm setting determines whether or not an alarm is issued in case of connection errors with each phase of power lines 4a, 4b, and 4c. The S-phase current anomaly detection setting determines whether or not an alarm is issued in case of a ground fault. Power measurement allows selection of whether to measure the power of the UV phase, VW phase, or single-phase three-wire system. Furthermore, alarm settings for offset and gain can be configured for the measured values ​​converted to industrial values.

[0040] The input type can be selected from current input (4-20mA), DI signal, voltage input (0-5V), and pulse input. The momentary voltage drop alarm setting is for alarms that occur when the voltage or other parameters temporarily drop. Additionally, a setting lock option allows you to choose whether or not to lock the above settings.

[0041] The specified setting information is not limited to the items shown in Figure 3; other items may be included, and some of the illustrated items may be omitted. Also, the "settings," "steps," and "units" in the figure are not limited to those shown.

[0042] Figure 4 is a diagram showing an example of the time-series change of measured values ​​in a power measuring device according to one embodiment of the present disclosure. In the graph shown, the horizontal axis represents time and the vertical axis represents the current value. The current value is the measured value of the load current supplied to the load 3 of the power supply system 1, and shows the time-series change of the current value when the work equipment 30 is normal and when there is an abnormality.

[0043] In the figure, A and B are time periods during which a predetermined working process in the working equipment 30 such as a factory is being carried out, and hereinafter they are referred to as "Process A" and "Process B", respectively. Process A and Process B may be, for example, cutting processes when machining a workpiece such as a key using a cutter, and may be processes for cutting different parts of the key, respectively. Also, Th1 in the figure is the threshold value of the current value in Process A, and Th2 is the threshold value of the current value in Process B.

[0044] When there is an abnormality in the working equipment 30, the measured values such as the current value of the load 3 included in the working equipment 30 measured by the power measurement device 10 often become different from the normal values. For example, when machining using a drill, if the drill is worn, the current value supplied to the working equipment 30 increases. As shown in the figure, when the current value in Process A exceeds the threshold value Th1, the determination unit 14 determines that there is an abnormality in the working equipment 30. Also, when the current value in Process B exceeds the threshold value Th2, the determination unit 14 determines that there is an abnormality in the working equipment 30.

[0045] When the determination unit 14 determines that there is an abnormality in the working equipment 30, the time-series change of the current value is recorded in the recording medium 11 in association with the occurrence date and time of the abnormality. The recording of the waveform in the recording medium 11 may be performed in a preset time period. By doing so, the user can compare the change in the waveform of the time-series change of the measured values such as the current value for each time period, and identify the cause of the abnormality in the working equipment 30.

[0046] <Power Measurement Method> Figure 5 is a sequence diagram for explaining a power measurement method according to an embodiment of the present disclosure. The state diagnosis method is executed by the power measurement device 10. <S101><S102>In the recording medium 11, various data such as dummy data simulating the measured values including at least any one of the current values and voltage values of the power lines 4a, 4b, 4c and predetermined setting information are recorded in advance (S101). When the reading unit 12 of the power measurement device 10 detects that the recording medium 11 is loaded when the power measurement device 10 is powered on, it reads a file of predetermined setting information and the like recorded in the recording medium 11 (S102).

[0048] The communication unit 13 of the power measurement device 10 receives the provision request information from the monitoring device 20 (S103). Then, it transmits response information including dummy data simulating measurement values including at least any one of the current values and voltage values of the power lines 4a, 4b, and 4c to the monitoring device 20 for the provision request information (S104).

[0049] The communication unit 13 determines the availability of communication with the monitoring device 20 based on whether or not to transmit response information for the provision request information received from the monitoring device 20 (S105). The power measurement device 10 measures measurement values such as the current values and voltage values of the power lines 4a, 4b, and 4c (S106). At this time, the determination unit 14 of the power measurement device 10 determines the presence or absence of an abnormality based on the measured measurement values and a predetermined threshold value of the measurement values (S107). The measurement results such as the measured measurement values and the presence or absence of an abnormality are recorded on the recording medium 11 (S108) and transmitted to the monitoring device 20 (S109).

[0050] When the calculation unit 15 of the power measurement device 10 receives a trigger signal when starting a predetermined work process from the work equipment 30 that performs a predetermined work process (S110), it starts calculating the amount of power consumed in the predetermined work process and calculates a power amount integrated value (S111). The calculated power amount integrated value is recorded on the recording medium 11 (S112) and transmitted to the monitoring device 20 (S113).

[0051] By these steps, the power measurement method according to an embodiment of the present invention is implemented. However, the power measurement method according to an embodiment of the present invention may appropriately include other steps according to measurement conditions, measurement environments, and the like.

[0052] <Effect> The power measurement device 10 can automatically perform settings such as initial settings based on a file in which data such as predetermined setting information recorded on the recording medium 11 is copyable. Therefore, the man-hours for initial settings for a plurality of power measurement devices 10 can be reduced, and the occurrence of setting errors can be suppressed.

[0053] Furthermore, the recording medium 11 contains dummy data that simulates measured values, including at least one of the current and voltage values ​​of the power lines 4a, 4b, and 4c. Therefore, even if a power measuring device 10 is newly installed and there are no measured values ​​such as current values ​​yet, various tests such as communication tests can be performed by transmitting dummy data to the monitoring device 20. In addition, the man-hours required to set the dummy data in the power measuring device 10 are reduced.

[0054] Therefore, the power measuring device 10 according to this embodiment can reduce the amount of work required for initial setup.

[0055] As described above, embodiments have been explained, but these embodiments are presented as examples only, and the present invention is not limited by these embodiments. The above embodiments can be implemented in various other forms, and various combinations, omissions, substitutions, and modifications are possible without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents.

[0056] This application claims priority to Japanese Patent Application No. 2024-162007, filed with the Japan Patent Office on September 19, 2024, which is incorporated herein by reference to its entire contents.

[0057] 1 Power supply system 10 Power measuring device 11 Recording medium 12 Reading unit 13 Communication unit 14 Judgment unit 15 Calculation unit 20 Monitoring device 30 Work equipment

Claims

1. A power measuring device connected to a power line, comprising: a reading unit that detachably loads a recording medium and reads predetermined setting information recorded on the recording medium; and a communication unit that receives a request for information from a monitoring device and transmits a response information to the monitoring device that includes dummy data simulating a measured value including at least one of the current value and voltage value of the power line in response to the request for information.

2. The power measuring device according to claim 1, wherein the reading unit, when powered on to the power measuring device, detects that the recording medium is loaded and reads the predetermined setting information recorded on the recording medium.

3. The power measuring device according to claim 1, wherein the predetermined setting information includes items relating to alarms corresponding to the measured value.

4. The power measuring device according to claim 1, wherein the communication unit determines whether or not to communicate with the monitoring device based on whether or not to transmit the response information to the provision request information received from the monitoring device.

5. The power measuring device according to claim 1, further comprising a determination unit that determines whether or not there is an abnormality based on the measured value and a threshold value of the measured value.

6. The power measuring device according to claim 5, wherein the determination unit determines whether or not there is an abnormality based on the time-series change of the measured value and the threshold value of the measured value.

7. The power measuring device according to claim 1, further comprising a calculation unit that receives a trigger signal from work equipment performing a predetermined work process, starts calculating the amount of power consumed in the predetermined work process, and calculates an integrated value of power.

8. A power measurement method performed by a power measuring device connected to a power line, comprising the steps of: loading a recording medium in a removable manner and reading predetermined setting information recorded on the recording medium; and receiving a request for information from a monitoring device and transmitting a response to the monitoring device, which includes dummy data that simulates a measured value including at least one of the current value and voltage value of the power line in response to the request for information.

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