KR101341107B1 - Adaptive safety diagnosis power meter - Google Patents

Abstract

According to an embodiment of the present invention, an active power meter for measuring power transferred through an external power line comprises an input contact part which is an input terminal of the power line, an output contact part which is an output terminal of the power line, a measurement part which is mounted on the power line to detect a power factor of the power by sensing a value of the transferred current or analyzing a power signal, temperature sensing parts which are respectively mounted in the input contact part and the output contact part to sense the temperature, a control part for determining whether or not there is a leakage current from the current value measured by the measurement part and determining whether or not there is an overheat from the temperature values measured by the temperature sensing parts, and a display part for displaying whether or not there are the leakage current and the overheat of the power meter according to the control of the control part, wherein the control part transmits information corresponding to the sensed values to a user when determining an abnormal operation from the values sensed by the measurement part and the temperature sensing parts. [Reference numerals] (10) Circuit breaker; (110) Temperature sensing part; (120) Measurement part; (130) Spark detection part; (140) Display part; (150) Control part; (160) Commumication part; (20) Server; (30) House/Building

Description

Adaptive safety diagnosis power meter

The present invention relates to a wattmeter, and in particular, in order to prevent failure or malfunction of the wattmeter in advance, it is possible to detect high temperature, overcurrent, arc voltage, power factor and high frequency (THD), and to the wattmeter that can inform the information thereof. It is about.

Mechanical wattmeters have been widely used and used, but digital wattmeters have been increasingly used in recent years. For example, KEPCO plans to replace mechanical electricity meters with digital electricity meters by 2015, and is in the process of gradually replacing them.

The digital electricity meter converts an analog signal into a digital signal and measures the amount of power. For this purpose, a memory, a CPU, and the like are provided. In addition to the basic functions of power measurement, additional functions such as remote meter reading through communication function are added to enable the use of a high-performance, multi-function power meter. However, as functions increase and high-performance components are provided, the probability of occurrence of failure also increases.

In addition, smart grids and micro grids are being applied to each home and residential environment. In order to provide a real-time plan and improved power service in the smart grid environment, a digital electricity meter must be provided. In the smart grid environment, the digital electricity meter communicates in both directions to control the amount of electricity in the residential environment. If the digital electricity meter fails, service disruption may occur.

In particular, when an operator installs a electricity meter, when there is a defect in assembly, a construction failure, or when an electrical abnormality occurs in the operation process, a leakage current may occur in the electricity meter, and it is impossible to check this. There is. In addition, if the leakage current is not confirmed, it may lead to a fire, which requires accurate diagnosis and detection.

The present invention accurately monitors whether leakage current occurs in the electricity meter due to poor assembly or construction failure by an operator, and furthermore, if such leakage current is detected, an active safety diagnostic electricity meter capable of informing the operator or the administrator of the defect. I would like to propose.

In addition, the present invention proposes an active safety diagnostic power meter capable of monitoring contact failure, arc voltage occurrence, power factor or high frequency generation, and informing the user of the results of these results.

An active safety diagnostic power meter according to the present embodiment is an electric power meter for measuring the amount of power transmitted through an external power supply line, comprising: an input contact portion serving as an input terminal of the power supply line, an output contact portion serving as an output terminal of the power supply line; A temperature sensor provided on the power line and mounted on each of the input contact part and the output contact part for sensing a power factor by sensing a value of a transmitted current or analyzing a power signal; A control unit for determining whether a leakage current is generated from a current value measured through the measurement unit, and whether or not to overheat from a temperature value measured through the temperature sensor unit, and a leakage current generation of the electricity meter under the control of the controller. And a display unit displaying whether or not to overheat, and the control unit includes the measurement unit and the temperature sensor unit. To the sensed value from the, if judged not to be a normal operation, characterized in that the transmission information corresponding to the sensed value of the at the user side.

The active safety diagnostic power meter, as proposed, can detect leakage current, arc voltage, overheating, power factor, and harmonic distortion that can cause a breakdown or fire of the power meter. Since it can be actively delivered to the user side, there is an advantage that can prevent accidents in advance.

1 is a block diagram showing the configuration of an active power meter according to an embodiment of the present invention.
2 is a diagram illustrating an external configuration of an active watt hour meter according to an embodiment of the present invention.
3 is a diagram schematically showing an internal configuration of an active watt-hour meter according to an embodiment of the present invention.
4 is a diagram for describing a method of detecting generation of an arc voltage in a wattmeter using a Fourier transform according to an embodiment of the present invention.
5 is an example of signal analysis for explaining a process of determining whether harmonic distortion (noise) is included in a voltage or current signal in a wattmeter according to an embodiment of the present invention.

Hereinafter, the present embodiment will be described in detail with reference to the accompanying drawings. It should be understood, however, that the scope of the inventive concept of the present embodiment can be determined from the matters disclosed in the present embodiment, and the spirit of the present invention possessed by the present embodiment is not limited to the embodiments in which addition, Variations.

1 is a block diagram showing the configuration of an active power meter according to an embodiment of the present invention.

Referring to FIG. 1, the active watt hour meter 100 includes a circuit breaker 10 disposed on a path through which power is supplied from a KEPCO or an external power generator that supplies power, and a home or building 30 that receives power. Is located between).

The active watt hour meter 100 includes a temperature sensor unit 110 for sensing whether high temperature heat is generated by a voltage (current) transmitted through the breaker 10, whether the leakage current is generated, and whether the power factor is generated. The measurement unit 120 for sensing, the spark detector 130 for detecting the arc voltage and harmonics inside the wattmeter, and the controller 150 for determining the risk of the wattmeter from the information transmitted through the sensing means. Include.

In addition, the active meter 100, the display unit 140 to display the current status or whether the risk of the electricity meter under the control of the controller 150, and the communication unit 160 capable of network connection to inform the user of the state of the electricity meter More).

Components included in the active watt hour meter 100 of the present embodiment will be described in more detail with reference to FIGS. 2 to 4.

2 is a diagram showing an external configuration of an active meter according to an embodiment of the present invention, Figure 3 is a diagram showing an internal configuration of an active meter according to an embodiment of the present invention, Figure 4 is an embodiment of the present invention FIG. 4 is a diagram for explaining a method of detecting generation of an arc voltage in a power meter using a Fourier transform.

The temperature sensor unit 110 of the active watt hour meter 100 may be mounted at a contact area of the watt hour meter and detect overheating due to an increase in the junction resistance. This will be described with reference to FIG. 3.

Referring to FIG. 3, a wattmeter is generally physically coupled to a meter and a power line by using a volt, which includes an input contact portion 101 positioned at an input portion of a power line, and an output contact portion positioned at an output portion of a power line. 101). When the meter is bolted to the meter and the power line, if the physical joint of the bolt joint is loosened, the joint resistance may increase and heat may be generated.

As described above, in order to detect the occurrence of overheating due to incomplete bonding with the external power line, at least one temperature sensor 110 is mounted according to the present embodiment. The temperature sensor unit 110 may include, for example, first to fourth temperature sensors. In this case, first and second temperature sensors 111 and 112 may be provided at the input contact unit 101. The third and fourth temperature sensors 113 and 114 are provided at the output contact 102.

Each of the first and second temperature sensors 111 and 112 is mounted to the positive and negative lines of an external power line in the input contact region, and each of the third and fourth temperature sensors 113 and 114 is an output contact portion. It is mounted on each of the positive and negative wires of the external power line in the area.

The temperature of the contact area detected by the temperature sensors is transmitted to the controller 150, and the controller 150 is overheated through the display unit 140 when the controller 150 is overheated above a preset temperature. It can be known or through the communication unit 160 may deliver notification information, such as e-mail / message of the specified user. In addition, although not shown, when a speaker is provided in the electricity meter, a warning sound may be generated.

In addition, when it is determined that the controller 150 is overheated, the control unit 150 may transmit a control signal to the breaker side connected through the power line so that power is not transmitted to the power meter side.

In FIG. 2, the display unit 140 shown on the user side is illustrated. Referring to FIG. 2, the active electricity meter 100 according to the embodiment is an electronic meter displaying the amount of power applied through a power line and transferred to homes or buildings, and includes a power display window 1 on which power used is displayed. In addition, according to the exemplary embodiment, the display unit 140 displays whether leakage current is generated, whether overheating occurs due to a temperature rise, and whether an arc voltage is generated.

As shown in FIG. 2, the display unit 140 may display a leakage current, an overheat, an arc voltage, an operating power factor, and a harmonic distortion (noise) through LEDs. However, the matters shown in these drawings are only examples, and the scope of the present invention is not limited to these matters.

Meanwhile, referring back to FIG. 3, the wattmeter of the present embodiment includes a measurement unit 120 mounted on a power line to measure voltage and / or current, and the measurement unit 120 is mounted on a positive power line. And a first current sensor 121 and a second current sensor 122 mounted on a negative power line.

Preferably, the first current sensor 121 and the second current sensor 122 are mounted on both power lines, and this indicates whether leakage current is generated from current values measured through each current sensor in order to detect leakage current. This is to accurately detect. If the current sensor is mounted only on any one of the two power lines, only the amount of power can be measured, and it is difficult to check whether leakage current is generated.

That is, the controller 150 has a leakage current when a difference occurs in the current value from a current value measured by each current sensor mounted on both the (+) power line and the (-) power line, over a preset range. You can judge that. When the controller 150 determines that a leakage current has occurred, the controller 150 may notify the user of the matter through the display unit 140 or the communication unit 160.

In addition, the measurement unit 120 serves to measure the power factor which means the ratio of the active power to the apparent power. The measurement unit analyzes the input power signal in detail and analyzes the phase of the voltage and current waveforms to calculate the effective power and the reactive power amount so that the user can check the ratio (power factor) of the active power and the reactive power of the power being used. The ratio is then analyzed as power factor. As a result, the user may enable efficient power usage through the reactive power ratio of the power used by the user.

Meanwhile, the active watt hour meter of the present invention includes a spark detector 130 for detecting an arc voltage, and the spark detector 130 monitors whether an arc is generated by analyzing a voltage and current signal measured by a meter. In accordance with the result, this information can be delivered to the user.

In particular, the spark detector 130 of the present embodiment performs signal analysis in the frequency domain in order to detect whether the arc voltage / current is more accurate. The measurement result of the voltage and current flowing in the electricity meter is transmitted to the spark detector 130, and the spark detector 130 converts the transmitted analog voltage / current signal into a digital signal.

The measured voltage or current signal is shown in FIG. 4 (a), and the spark detector 130 converts the transmitted voltage or current signal into a digital signal through an ADC. Next, the transformed digital signal is frequency transformed using a fast fourier transform (FFT) technique. And, from such frequency-converted information (FIG. 4 (b)), the spark detector transmits to the controller 150 whether an arc voltage or a spark current has occurred in the electricity meter.

In particular, when there is a voltage or current signal other than the preset power signal 131 (for example, 60 Hz) (132, 133, 134, 135), the spark detector 130 may determine that an arc voltage or a spark current has occurred. .

In addition, information on whether an arc is generated by the spark detector is transmitted to the controller, and the controller may send a warning message to the user through the display unit or the communication unit.

The spark detector may measure whether harmonic distortion is present, and the controller may notify the user of such information when the harmonic distortion is greater than a predetermined value in the voltage or current signal from the result measured by the spark detector.

If harmonic distortion occurs in the voltage or current signal, the upper and lower limits of the phase may become peak values due to the harmonic distortion, and it is difficult to accurately measure the signal having such a phase. Therefore, the spark detector of the present invention determines whether noise due to harmonic distortion is included in the voltage or current signal for measuring the use power or more than a predetermined reference level.

For example, similar to the measurement of arc voltage or spark current mentioned above, the transmitted voltage or current signal is converted into a digital signal through an ADC and frequency converted by the converted digital signal. From the frequency-converted information (FIG. 5), the degree of harmonic distortion is analyzed on the transmitted voltage or current waveform.

For example, if a voltage or current signal other than a predetermined power signal (for example, 60 Hz) 138 in the range of 0 to 600 kHz has a frequency having a value higher than or equal to a preset reference level, harmonic distortion is set at the reference frequency. It is judged to be included in excess.

That is, the spark detector may determine whether a spark has occurred in the voltage or current signal, and determine whether the harmonic distortion and the degree of the harmonic distortion are together.

By the active wattmeter of the embodiment as described above, the wattmeter can actively detect and notify the leakage current, the detection and notification of the risk of fire caused by high temperature, the detection and notification of the arc generation.

Claims (7)

A wattmeter for measuring the amount of power delivered through an external power line,
An input contact portion serving as an input terminal of the power supply line,
An output contact portion serving as an output terminal of the power supply line,
A measurement unit provided at each phase of the power line and configured to detect a power factor by sensing a value of a transmitted current or analyzing a power signal;
A temperature sensor unit mounted to each of the input contact unit and the output contact unit to sense temperature;
A controller for determining whether leakage current is generated from the current value measured through the measurement unit, and determining whether to overheat from the temperature value measured through the temperature sensor unit;
A display unit displaying whether a leakage current of the electricity meter is generated and whether it is overheated under the control of the controller;
The control unit, when it is determined that the operation is not normal from the values sensed through the measurement unit and the temperature sensor unit, delivers the information corresponding to the sensed value to the user side,
When the power factor value measured by the measuring unit is smaller than a preset value, the controller transmits the content including the information on the measured power factor value to the user side,
The temperature sensor unit includes first and second temperature sensors mounted on the (+) and (-) lines of the input contact unit, respectively, and third and the third mounted on the (+) and (-) lines of the output contact unit, respectively. Active safety diagnostic power meter with temperature sensor. delete The method of claim 1,
Further comprising a spark detector for detecting whether an arc occurs from the voltage value or current value inside the wattmeter,
The spark detection unit digitally converts the measured voltage value or current value of the analog signal, and frequency-converts the digitally converted signal to determine that a spark has occurred when there is a signal corresponding to a frequency other than a preset frequency. ,
The controller is an active safety diagnostic power meter for transmitting information indicating the operation risk of the electricity meter to the user side. The method of claim 1,
A spark detector further detects whether a spark is generated from a voltage value or a current value inside the electricity meter.
The spark detector digitally converts the measured voltage value or the current value of the analog signal, and frequency-converts the digitally converted signal to generate noise when a power component of a frequency band other than a predetermined frequency is larger than a preset reference level. Judging by
The control unit is an active safety diagnostic power meter for transmitting to the user information that the noise due to the harmonic distortion in the voltage or current inside the wattmeter. delete The method of claim 1,
The measuring unit includes a current sensor disposed on the power line of each phase,
And the control unit compares the current value measured by the current sensor, and determines that there is a leakage current when a difference occurs over a predetermined range. The method of claim 1,
The control unit displays the safety state of the voltage supply through the display unit, active safety diagnostic power meter, characterized in that to provide information of the notification to the preset user side when an electrical abnormality occurs.

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