JP2009014659A - Deemed power value output current monitoring device by own power source system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a current monitoring measurement device capable of safely and easily measuring and excellent in economic efficiency, for visualizing the amount of power consumption on real time for cost reduction by electric energy saving, to provide a measurement device which does not have to carry out direct connection to a power line, and to provide a current monitoring and measuring device, the driving electric power source of which is a self electric power source system without needing 100 V electric power source or electric battery. <P>SOLUTION: This device which is equipped without voltage input terminals like as a conventional watt meter calculates the deemed power value and obtains the integrated value by using the rating voltage of the installation place preset in the CPU memory and the current value detected by the device for realizing saving work and low cost, thus outputting the result to a real time power monitoring system which is a backward system. The electric energy for activating this device is secured by the electromagnetic induction through the current transformers from the power line to be measured, and the unevenness of the power generation is coped with a super capacitor, therefore the external power source or electric battery is not needed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention makes it possible to visualize electricity consumption in real time in order to effectively promote cost savings through energy saving and CO2 emission reduction, which is a greenhouse gas. The present invention relates to a current monitoring and measuring apparatus that can measure the current and is excellent in economy.

Since voltage measurement is required for conventional power consumption monitoring and measurement, it is necessary to connect the measurement device directly to the power line of the circuit to be measured. For this reason, connection work is dangerous, wiring becomes complicated, and troubles such as poor contact and short circuit may occur.
For this reason, each electric power company installs a power trading meter on the high voltage side for customers who consume 50kw or more of electricity, and conducts meter readings of monthly power consumption. The metering pulse is provided from there. Conventionally, customers who have demanded electricity can measure the amount of electricity used by using this measurement pulse.

However, since this measuring pulse is a flow of a transient pulse, the counting device that counts it was not allowed to stop counting or pause every minute. Further, as a driving power source for the counting device, it is necessary to supply power from a low voltage power source of 100V or 200V, or to attach a battery to the counting device. In this case, when a transaction meter is installed outdoors, there is a problem in that the construction of the power supply line is complicated or the battery needs to be replaced periodically.
In addition, customers with high power demand have multiple high-voltage transformers installed underneath the power company's trading meters. When measuring and monitoring the power consumption of each of these high-voltage transformers, use measurement pulses. There was a problem that it was not possible.
JP 06-058960 JP 2000-338141 A

  The main problem to be solved by the present invention is to provide a measuring device that does not need to be directly connected to a power line, and the driving power source of the device is a self-powered current monitoring measurement that does not require a 100 V power source or a battery. Is to provide a device. This is to provide a device that realizes the visualization of electricity consumption in a cheap, safe and real-time manner for energy saving. In addition, the measured data is sent to the back-end processing system using a communication module and processed, and the real-time trend graph is provided by a web application via the Internet, realizing the popularization of energy-saving activities. is there.

In order to solve the above-mentioned problems, the present invention does not measure voltage, performs current measurement, and regards the amount of electric power to be regarded as a numerical value, and current that is electromagnetically induced from the power line to be measured for electric energy for operating the apparatus. The problem is solved by supplying the printer with the following configuration.
The present invention is to measure the load current of the power line, in order to measure the load current of the power line, an annular current transformer CT1 that is mounted in a contactless manner, and a non-power source for taking out the power for self-power supply by electromagnetic induction by the load current of the power line. A current transformer CT2 mounted by contact, a power supply module connected to the current transformer CT2 and a large-capacity capacitor, a memory for storing a rated voltage value parameter of the power line, and a current from the current transformer CT1 are digitally And a communication module for transmitting the processed data, and using the voltage value parameter of the memory, the measured current value is not converted into the power value, and the data is periodically communicated. It is a thing.

Further, the present invention comprises a pulse input circuit for receiving the power value pulse when the power value pulse sent from the transaction power meter can be utilized, and based on the power value from the transaction power meter, the current transformer CT1 The assumed power value measured in (1) is corrected.

The power supply module further includes a semiconductor switch provided in a power supply path that supplies the communication module, detects a decrease in a measured current value flowing through a power line, shuts off the semiconductor switch, and supplies power to the communication module. It is intended to stop.

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The hardware of these measuring devices can be mounted in a small package and can be easily attached to the current test terminal exposed on the panel surface with less danger in the high-voltage power receiving panel, and also to the main breaker of the low-voltage circuit It can be installed.

  The current monitoring device of the present invention uses a non-contact current sensor, derives an electric power value from current measurement, and uses it as an energy saving index, thereby simplifying the structure of the electric power measurement unit and making installation work safe and easy. Can be done. Further, the power source required by the present apparatus eliminates the need for routing of the 100V power source line by using a current transformer from the power line to be measured by means of electromagnetic induction, or does not require a consumable battery. Therefore, installation and relocation are easy, and it has a great effect on the spread of energy conservation activities. As the data communication module, wireless, infrared, or PLC (power line carrier communication) can be used, and the transmitted data can be used for promoting energy saving activities, verifying the effectiveness of the activities, and managing energy intensity.

In order to carry out the invention,
As a means for measuring the load current of the power line, an annular current transformer CT1 (2) mounted in a non-contact manner on the measurement target power line (1) and the power for self-power supply are extracted by electromagnetic induction by the load current of the power line. A current transformer CT2 (5) mounted in a non-contact manner, and a power module (3) and a large-capacitance capacitor (4) are connected to the current transformer (5) to stabilize and level the power source. Make it.
The rated voltage value parameter of the power line is stored in the memory (9), the current from the current transformer CT1 is digitized by the CPU and calculated by the rated voltage value parameter, and the assumed power value is derived. Considered power data is transmitted by the communication module (6).
Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a diagram for explaining a specific embodiment of the apparatus of the present invention.
In FIG.
1 is a power line to be measured, 2 is an annular current transformer CT1 that measures the current of the power line, 3 is a power supply module of the device, 4 is a large-capacity capacitor, and 5 is a self-power supply energy extracted from the power line by electromagnetic induction Current transformers CT2 and 6 are communication modules that transmit the measured power data, 7 is a CPU that digitizes the current and performs data processing such as calculation of power values, 8 is a pulse input circuit that receives power metering pulses, and 9 is rated A memory for storing voltage value parameters, 10 is a semiconductor switch for supplying power to the communication module, and 11 is an antenna terminal or a signal terminal.
The signal detected by the current transformer CT1 is digitized by an A / D conversion circuit of the CPU to obtain an average current. The power consumption is calculated using the average current and the rated voltage value preset in the memory. The deemed power amount is intermittently transmitted to the rear processing device via the communication module at a preset transmission interval. Current transformer CT1 uses an annular current transformer with good linearity to measure accurate current.
On the other hand, the current induced by the current transformer CT2 is rectified by a power supply module and charged to a large-capacity capacitor to stabilize, and the current transformer CT2 has saturation characteristics and the voltage saturates even when a large current flows. I am using something. Also, when the load current value to be measured is small and the electrical energy that can be extracted is small, the induction current can be increased by winding the wire penetrating the current transformer CT2 multiple times and further increasing the number of current transformer CT2. . The power supply module supplies power to the CPU circuit and also supplies power to the communication module via the semiconductor switch.
The communication module uses wireless (radio wave, infrared) or power line carrier communication (PLC).
By the way, when the communication module is a PLC, the signal transformer CT2 and the power supply module are unnecessary because a low voltage DC current of about 5V is superimposed on the signal line from the receiving device side.

On the other hand, when a power value pulse is sent from the power meter for transaction, the power value for transaction is taken into the CPU via the pulse input circuit, and the assumed power value calculated from the current value measured by this instrument is corrected. I can do it. For example, the voltage value is calculated from the current value measured by this instrument, and the preset rated voltage value in the memory is corrected.
This calibration operation only needs to be performed once, and it is not necessary to constantly monitor the power pulse. With this correction, it is possible to measure a deemed power value close to the actual power value. The rated voltage value to be set in the memory can be changed at any time by causing the above-mentioned calibration operation to be performed by giving a command to the CPU from the rear processing system via the communication module. Here, the pulse input circuit is a buffer circuit provided with a noise filter for a pulse signal sent from a trading power meter, and its output is connected to an interrupt circuit of the CPU.

Although the self-power supply voltage of this unit is stabilized by a large-capacitance capacitor, it gradually decreases when the load current of the power line becomes very small. Therefore, a decrease in the current of the measurement target power line detected by the current transformer CT1 is detected, and the semiconductor switch is controlled by the CPU to cut off the power supply to the communication module with high power consumption. As the semiconductor switch, a CMOS or transistor semiconductor switch can be used. As a result, the decrease in the power supply voltage can be sufficiently delayed, and the operation of the communication module can be recovered again when the load current is recovered.
This does not apply when a PLC is used for the communication module.
This unit is equipped with an energy-saving CPU that operates with minute current.

FIG. 2 is a block diagram illustrating a small package that houses the current monitoring device of the present invention. The small package has a movable metal measurement terminal, and the current measurement terminal of the device is connected to the metal measurement terminal. Yes. Since the metal measuring terminal of the small package is movable, the connection to the power line to be measured is flexible.
FIG. 3 shows a method of measuring the package of FIG. 2 by connecting it to a current test terminal in a high voltage power receiving panel.
When installing the instrument, connect the instrument to avoid opening the current transformer connected to the current test terminal.
FIG. 4 is a diagram showing a method of connecting a small package containing the current monitoring device of the present invention to a low voltage switchboard via a switchable current transformer.
In the low-voltage switchboard, the power flowing through the low-voltage switchboard can be measured equivalently by clamping and measuring the split current transformer CT3 as shown in FIG.

  If the power consumption is real-time and the time trend can be seen in a graph, it is easy to find irregularities and waste of electricity use, and the results of some energy-saving activities can be immediately verified, so the PDCA cycle can be turned. In such energy-saving activities, it is desirable that a measuring device for viewing power consumption in real time is low in cost and safe and simple to install. Since the present invention gives a practical answer to such a demand, it can contribute to energy saving activities which are the current worldwide demand.

It is a block diagram of the apparatus explaining the implementation method of the self-power-supply-type current monitoring apparatus of this invention. It is a block diagram explaining the small package which accommodates the current monitoring apparatus of this invention. It is the figure which showed the method of connecting the small package which accommodates the current monitoring apparatus of this invention to the current test terminal of a high voltage receiving board. It is the figure which showed the method of connecting the small package which accommodates the current monitoring apparatus of this invention to a low voltage switchboard via a switching type current transformer.

Explanation of symbols

1: Measurement target power line
2: Current transformer CT1
3: Power supply module
4: Large capacitor
5: Current transformer CT2
6: Communication module
7: CPU
8: Pulse input circuit
9: Memory
10: Semiconductor switch
11: Antenna / signal terminal
12: Small package
13: Metal measuring terminal
14: Split-type current transformer CT3
15: Low voltage switchboard main breaker

Claims (4)

In a device that monitors power in real time, in order to measure the load current of the power line, the ring-shaped current transformer CT1 that is attached to the power line in a contactless manner and the electromagnetic power generated by the load current of the power line is used to generate power for self-power supply. A current transformer CT2 to be mounted in a contactless manner, a power supply module connected to the current transformer CT2, a large-capacitance capacitor, a memory for storing a rated voltage value parameter of the power line, and the current transformer CT1 A signal processing unit for digitizing the current of the current and a communication module for transmitting the processed data, and using the voltage value parameter of the memory, the measured current value is converted into an electric power value without regular processing. Self-powered current monitoring device characterized by communicating with 2. The current monitoring device according to claim 1, further comprising a pulse input circuit that receives a power value pulse sent from a transaction power meter, and measured by the current transformer CT1 based on a power value from the transaction power meter. A self-powered current monitoring device characterized by correcting the assumed power value. The current monitoring device according to claim 1, further comprising a semiconductor switch provided in a power supply path that supplies power to the communication module from the power supply module, and detects a decrease in a measured value of a current flowing through a power line, and shuts off the semiconductor switch. A self-powered current monitoring device characterized by stopping the supply of power to the communication module. In the current monitoring device according to claim 1,
A small package containing the current monitoring device; and a movable metal measuring terminal provided in the small package and connected to the current monitoring device. The high voltage power receiving board has the movable metal measuring terminal connected to the high voltage A self-powered current monitoring device characterized in that it is connected to the current test terminal of the power receiving panel, and in the low voltage distribution panel, it is connected to the main breaker via a switching current transformer.

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