KR101721574B1 - Electronic power meter - Google Patents

Abstract

The present invention relates to an electronic power meter having a shielding and an anti-static function. It is possible to prevent the operation abnormality and the metering stoppage of the electronic power meter due to the influence of a magnetic field. It is robust against the operation abnormality due to the magnetic field and is capable of stable metering by allowing the metering of the power meter to be performed by using auxiliary power even if the metering of the power meter is stopped by the magnetic field. The electronic power meter includes a shielding cap, an auxiliary power supply, and switches.

Description

An electronic watt-hour meter with integrated shielding and power failure compensation {Electronic power meter}

The present invention relates to an electronic watt-hour meter, and more particularly, to an electronic watt-hour meter having a shielding and power-saving function.

Korean Patent Laid-Open No. 10-2009-0008763 (2009.01.22) proposes an electronic watt-hour meter. If a magnet is attached to a power transformer used in an SMPS (Switching Mode Power Supply) used as a power source of an electronic watt-hour meter, the operation of the electronic watt-hour meter and metering stop phenomenon occur due to the magnetic field formed by the magnet, When the magnet is removed, it returns to its original state and the electronic watt hour meter re-operates.

As a result, a malicious user usually stops measuring the amount of electricity by attaching a magnet to the power transformer of the power source of the electronic watt hour meter, and then removes the magnet from the power source transformer only at the time of visit to the meter reading unit and restarts the electronic watt- .

Therefore, the inventor of the present invention has studied an electronic watt-hour meter with a built-in shielding and power-saving function by minimizing the influence of the magnetic field and realizing the weighing of the watt-hour meter by using the auxiliary power source even if the weighing of the watt- .

Korean Patent Publication No. 10-2009-0008763 (2009. 01. 22)

It is an object of the present invention to provide an electronic watt-hour meter with built-in shielding and power failure compensation function that can prevent an operation abnormality and a metering stop phenomenon of an electronic watt-hour meter due to the influence of a magnetic field.

It is still another object of the present invention to provide an electronic watt-hour meter including a shielding and an electric power-saving function capable of stable metering by allowing the metering of the watt-hour meter to be performed by using an auxiliary power source even when the metering of the watt-

According to an aspect of the present invention, there is provided an electronic watt-hour meter including a shielding and an electrostatic charge compensating function, a meter transformer for converting a high voltage of the power input side to a low voltage; A current transformer for converting a large current at a power input side into a small current; A controller for measuring a voltage converted by the meter transformer and a current changed by the meter current transformer to calculate an amount of power used; And a cap for shielding a magnetic field affecting the power transformer by covering the power transformer of the main power unit, including a main power unit for supplying a main power to the watt-hour meter.

According to a further aspect of the present invention, there is provided an electronic watt-hour meter including the shielding and power-saving function, the auxiliary watt-hour unit supplying an auxiliary power to the control unit; And a switch for switching the auxiliary power of the auxiliary power unit to be supplied to the control unit when the power failure of the main power unit is detected and a power failure of the main power unit is detected.

The electronic watt-hour meter according to the present invention can prevent the operation abnormality and the metering stop of the electronic watt-hour meter due to the influence of the magnetic field, so that it is robust against the operation abnormality caused by the magnetic field.

Further, even when the weighing of the watt-hour meter is stopped by the magnetic field, the present invention has an effect that the weighing of the watt-hour meter is performed by using the auxiliary power source, thereby enabling stable metering.

FIG. 1 is a view showing a configuration of an electronic watt-hour meter incorporating a shielding and power failure compensation function according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

The terms used throughout the specification of the present invention have been defined in consideration of the functions of the embodiments of the present invention and can be sufficiently modified according to the intentions and customs of the user or operator. It should be based on the contents of.

FIG. 1 is a view showing a configuration of an electronic watt-hour meter incorporating a shielding and power failure compensation function according to the present invention. 1, an electronic watt-hour meter 100 incorporating a shielding and power-saving function according to this embodiment includes a meter transformer 110, a meter current transformer 120, a controller 130, A power supply unit 140, and a cap 150 for shielding.

The PT (Potential Transformer) 110 transforms the high voltage on the power input side to a low voltage. Since the high voltage flowing in the power system can not be directly measured, it must be transformed to a low voltage through the meter transformer 110 and measured.

The CT (Current Transformer) 120 converts the large current at the power input side into a small current. Since the large current flowing in the power system can not be measured directly, it must be measured and converted to a small current through the meter current transformer 120.

The controller 130 measures the voltage converted by the meter transformer 110 and the current changed by the meter current transformer 120 to calculate the amount of power used. The control unit 130 may include a measurement unit 131 and an operation unit 132.

The measuring unit 131 measures a voltage changed by the meter transformer 110 and a current changed by the meter current transformer 120.

The calculating unit 132 calculates the amount of power to be used by using the voltage and current measured by the measuring unit 131. The power can be calculated by multiplying the current by the voltage.

The main power supply unit 140 supplies a main power to the watt-hour meter. In this case, a switching power supply (SMPS) may be used as the main power supply unit 140. Meanwhile, the main power supply unit 140 may include a power supply transformer 141 and a rectifying unit 142.

The power transformer 141 converts the commercial AC power to a low-voltage AC power. The rectifying unit 142 rectifies the transformed AC power and outputs a rated DC power. The rated DC power output from the rectifying section 142 is applied as an operating power source to the transformer 110 for the instrument which is the measuring module, the current transformer 120 for the instrument and the control section 130 which is the control module.

The shielding cap 150 covers the power supply transformer 141 of the main power supply unit 140 to shield the magnetic field affecting the power supply transformer. For example, the shielding cap 150 may be a material containing or coated with cobalt or a nickel alloy having a high porosity.

According to the present invention, the power supply transformer 141 of the main power supply unit 140 affected by the magnetic field is shielded through the shielding cap 150 so that it is not affected by the magnetic field, Even if the magnet is attached, the operation of the electronic watt-hour meter and the stoppage phenomenon do not occur, and stable metering is possible.

According to a further aspect of the present invention, the electronic watt-hour meter 100 having the shielding and power failure compensation function may further include an auxiliary power unit 160 and a switch 170.

The auxiliary power unit 160 supplies an auxiliary power to the controller 130. [ For example, the auxiliary power unit may be a rechargeable battery.

The switch 170 senses a power failure of the main power unit 140 and switches the auxiliary power of the auxiliary power unit 160 to be supplied to the controller 130 when the power failure of the main power unit 140 is detected. For example, when the switch 170 senses an abnormality in the power supply of the main power supply 140, it may be implemented as a switching transistor that applies a specific voltage to the gate to conduct a current between the collector and the emitter.

When the auxiliary power is supplied to the control unit 130 by the auxiliary power unit 160, the control unit 130 applies the auxiliary power to the transformer 110 for meters and the current transformer 120 for the instrument, , So that the meter current transformer 120 operates normally.

That is, this embodiment intentionally destroys the shielding cap 150, or even if the shielding cap 150 loses its shielding function and thus the operation of the electronic watt-hour meter and the metering stop phenomenon occur, The transformer 110 for a meter, the current transformer 120 for a meter, and the control unit 130, which is a control module, to operate normally without stopping the metering operation.

In FIG. 1, two diodes provided in each of the power supply lines between the main power supply unit 140 and the auxiliary power supply unit 160 and the control unit 130 function to prevent reverse current. Reference numeral 180 denotes a display unit such as an LED for displaying the amount of used electric power calculated by the control unit 130 and reference numeral 190 denotes a communication unit for externally wired or wirelessly transmitting the amount of electric power calculated by the control unit 130.

Industrial Applicability As described above, the electronic watt-hour meter according to the present invention is robust against an operation error caused by a magnetic field because it can prevent an operation abnormality and a stoppage phenomenon of an electronic watt-hour meter due to the influence of a magnetic field.

Further, even if the weighing of the watt-hour meter is stopped by the magnetic field, the weighing of the watt-hour meter can be performed rapidly by using the auxiliary power source, so that stable metering can be performed.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. .

INDUSTRIAL APPLICABILITY The present invention is industrially applicable in the technical field related to an electronic watt-hour meter and its application field.

100: Electronic watt hour meter
110: Instrument transformer
120: Current transformer for meters
130:
131:
132:
140:
141: Power transformer
142:
150: Shielding cap
160: auxiliary power unit
170: Switch
180:
190:

Claims (2)

A meter transformer for transforming the high voltage at the power input side to a low voltage;
A current transformer for converting a large current at a power input side into a small current;
A controller for measuring a voltage converted by the meter transformer and a current changed by the meter current transformer to calculate an amount of power used;
A main power unit for supplying main power to the watt hour meter;
In the watt-hour meter,
A shielding cap covering a power transformer of the main power unit and shielding a magnetic field affecting the power transformer, the shield being made of or containing cobalt or nickel alloy;
An auxiliary power unit for supplying auxiliary power to the control unit;
A switching transistor which is switched to supply an auxiliary power of the auxiliary power unit to the control unit by detecting a power supply abnormality of the main power unit and applies a specific voltage to the gate when a power supply failure of the main power unit is detected to conduct a connection between the collector and the emitter, ;
And an electronic watt hour meter incorporating a shielding and power failure compensation function. delete

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