KR20220093926A - Apparatus for detecting voltage and current - Google Patents

Abstract

The present invention relates to an apparatus for detecting a voltage and current, which comprises: a voltage sensor for detecting a voltage and outputting a voltage signal; a current sensor for detecting a current and outputting a current signal; a voltage signal amplifier for amplifying the voltage signal output from the voltage sensor and outputting a voltage signal for measurement; a current signal amplifier for measurement for amplifying the current signal output from the current sensor and outputting a current signal for measurement; an analog-to-digital converter for sampling the voltage signal for measurement and the current signal for measurement according to a sampling rate determined by a sampling signal and converting the same into digital data to generate voltage data for measurement and current data for measurement; a resampler for resampling and outputting the voltage data for measurement and the current data for measurement according to a resampling rate determined based on the sampling rate; and a motion control module for outputting the sampling signal to the analog-to-digital converter, comparing a phase of the resampled voltage data for measurement with a phase of the resampled current data for measurement to calculate phase difference data, and outputting the voltage data or current data for measurement by correcting the phase thereof. An objective of the present invention is to perform phase correction of a voltage and current, thereby enhancing reliability in an operation of the apparatus for detecting a voltage and current.

Description

Voltage current detection device {APPARATUS FOR DETECTING VOLTAGE AND CURRENT}

The present invention relates to a voltage and current detection device, and more particularly, to an electronic voltage and current detection device.

A transformer, which is an example of a voltage and current detection device, is divided into an electric transformer and an electronic transformer, and the electronic transformer is divided into a transformer that outputs an analog signal or a digital signal.

An electronic transformer that outputs an analog signal has the advantage of being able to use the output as it is without a special signal converter or use it after undergoing some signal correction.

On the other hand, an electronic transformer that outputs a digital signal can transmit and receive data to another remote device through communication using an optical cable or the like.

These electronic transformers are devices for converting current and voltage used together with electrical instruments or measuring devices, including instrument current transformers (CT) and instrument transformers (PT). to allow it to function normally.

An electronic transformer is also an electrical device that converts the primary current or voltage of a current or voltage into a secondary current or voltage suitable for the connected equipment (eg, measuring instrument, wattmeter or protective relay, etc.). , If you apply extra-high voltage directly to equipment such as a watt-hour meter or a protection device, the equipment is damaged.

Republic of Korea Patent Registration No. 10-0765344 (Announcement Date: October 10, 2007, Title of Invention: Electric and Electronic Combined Voltage and Current Detector) Republic of Korea Patent No. 10-1099953 (Announcement Date: December 28, 2011, Title of Invention: Electronic Transformer for Composite Insulation Instrument)

The problem to be solved by the present invention is to improve the reliability of the operation of the voltage and current detection device by performing phase correction of voltage and current.

A voltage and current detection device according to one aspect of the present invention for solving the above problems is a voltage sensor that detects a voltage and outputs a voltage signal, a current sensor that detects a current and outputs a current signal, and is connected to the voltage sensor, A voltage signal amplifying unit for amplifying the voltage signal output from the voltage sensor and outputting it as a voltage signal for measurement, is connected to the current sensor, amplifies the current signal output from the current sensor and outputs it as a current signal for measurement is connected to the current signal amplification unit for measurement, the voltage signal amplification unit and the current signal amplification unit for measurement, and samples the voltage signal for measurement and the current signal for measurement according to a sampling ratio determined by the sampling signal to obtain digital data An analog-to-digital converter that changes to and generates voltage data for measurement and current data for measurement, is connected to the analog-to-digital converter, and is connected to the voltage data for measurement and It is connected to the resampling unit and the resampling unit for resampling and outputting current data for measurement, and outputs the sampling signal to the analog-to-digital converter, and the resampled voltage data for measurement and the resampled current for measurement and an operation control module for calculating phase difference data by comparing the phases of the data, and correcting and outputting the phase of voltage data or current data for measurement.

When the sampling rate and the resampling rate are the same, the resampling unit delays each phase of the voltage data for measurement and the current data for measurement by using a minute delay filter, and the resampling rate is higher than the sampling rate In this case, the interpolation method is applied to each of the measurement voltage data and the measurement current data to obtain data and perform a resampling operation, and then perform a phase correction using a minute delay filter, and perform the re-sampling than the sampling rate. When the ratio is low, after filtering each of the voltage data for measurement and the current data for measurement using a Gaussian filter, the phase may be corrected using a minute delay filter.

The operation control module operates according to a synchronization signal and compares the phases of the resampled measurement voltage and the resampled measurement current to output a phase difference data phase comparator, an amplitude correction target and an amplitude correction value, and re-sampled measurement current. A memory for storing delayed data information, which is information of delayed data among the sampled measurement data and the resampled measurement current data, is connected to the phase comparator and is delayed using the phase difference data applied from the phase comparator Correcting the phase of the re-sampled voltage data for measurement or the re-sampled current data corresponding to the data information, correcting the phase of the re-sampled voltage data for measurement or the re-sampled current data, stored in the memory a control unit for correcting the amplitude of the resampled measurement voltage data or the resampled current data using the amplitude correction target and the amplitude correction value; and an oscillator that operates under the control of the control unit to generate a synchronization signal and a sampling signal and respectively output the synchronization signal and the sampling signal to the analog-to-digital converter and the phase comparator.

The voltage-current detection device according to the above characteristics cuts off the DC components of each of the voltage signal for measurement and the current signal for measurement that are output from the voltage signal amplifying unit and the current signal amplifying unit for measurement and output to the analog-to-digital conversion unit It may further include a DC component blocking unit.

The voltage and current detection device according to the above feature is connected to the operation control module, and converts the corrected voltage data for measurement and the measurement current data output from the operation control module into analog signals and outputs digital-analog conversion, respectively. It may include more wealth.

The voltage and current detection device according to the above feature A first temperature sensor positioned adjacent to the voltage sensor to sense the temperature of the voltage sensor and outputting a first temperature signal to the analog-to-digital converter, and a first temperature sensor positioned adjacent to the current sensor to detect the temperature of the current sensor The second temperature signal may further include a second temperature sensor for outputting the analog-to-digital converter, wherein the analog-to-digital converter converts the first temperature signal and the second temperature signal into digital data, respectively, to obtain a first temperature data and second temperature data may be output to the resampling unit, and the resampling unit resampling the first temperature data and the second temperature data according to a resampling rate determined based on the sampling rate to control the operation module, wherein the operation control module calculates a temperature correction value corresponding to the first temperature data on the voltage data for measurement performed as a phase correction, and performs temperature correction on the voltage data for measurement performed as a phase correction do,

A temperature correction value corresponding to the second temperature data may be calculated on the measurement current data that is a phase correction, and the temperature correction of the measurement current data that is a phase correction may be performed.

According to this feature, since the phase difference from the Rogowski coil current measurement method of the capacitive non-contact voltage measurement method and the magnetic field non-saturation method is corrected, the precision of power measurement using voltage, current, and the phase difference between voltage and current can be improved. .

In this case, since the phase difference between the voltage signal and the current signal is corrected by using the minute delay filter, the accuracy of the phase difference correction is improved.

Furthermore, since a new voltage signal and a current signal are generated by resampling the voltage signal and the current signal to which the phase difference correction has been performed, the accuracy of the signal is further improved.

1 is a schematic block diagram of an apparatus for detecting voltage and current according to an embodiment of the present invention.
FIG. 2 is a schematic block diagram of the operation control module shown in FIG. 1 .

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In describing the present invention, if it is determined that adding a detailed description of a technique or configuration already known in the field may make the gist of the present invention unclear, some of it will be omitted from the detailed description. In addition, the terms used in this specification are terms used to properly express embodiments of the present invention, which may vary according to a person or custom in the relevant field. Accordingly, definitions of these terms should be made based on the content throughout this specification.

The terminology used herein is for the purpose of referring to specific embodiments only, and is not intended to limit the invention. As used herein, the singular forms also include the plural forms unless the phrases clearly indicate the opposite. As used herein, the meaning of 'comprising' specifies a particular characteristic, region, integer, step, operation, element and/or component, and other specific characteristic, region, integer, step, operation, element, component, and/or group. It does not exclude the existence or addition of

Hereinafter, a voltage-current detecting apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings.

The voltage and current detection device of the present example may be applied to an electronic transformer, but is not limited thereto.

First, referring to FIG. 1 , the voltage and current detection device of this example includes a voltage signal amplifier connected to the voltage sensor unit 11 , the current sensor unit 12 , the temperature sensor unit 13 , and the voltage sensor unit 11 . (21), the current signal amplification unit 22 for measurement connected to the current sensor unit 12, the protection current signal amplification unit 23 connected to the current sensor unit 12, the amplification unit 21-23 and a DC component blocker 30 connected to the temperature sensor unit 13, an analog-to-digital conversion unit (A-D conversion unit) 40 connected to the DC component blocker 30, an analog-to-digital conversion unit ( The resampling unit 50 connected to 40), the operation control module 60 connected to the resampling unit 50, the memory 70 connected to the operation control module 40, the operation control It may include a digital-to-analog converter (D-A converter) 80 connected to the module 40 , and a communication module 90 connected to the operation control module 40 .

The voltage sensor unit 11 may include at least one voltage sensor, and each voltage sensor may detect a voltage applied to the power equipment to which it is mounted and output an analog signal, that is, a voltage signal.

In this case, the number of voltage sensors may be determined according to at least one of the magnitude, position, and measurement precision of the voltage to be sensed.

In this example, the voltage sensor may secure insulation performance by using a capacitive type capacitor sensor. In this case, the voltage sensor 111 may detect a capacitance and output a voltage proportional to the sensed capacitance.

The current sensor unit 12 may also include at least one current sensor, and each current sensor detects a current flowing through the power equipment to which it is mounted and outputs it as an analog signal (eg, a current signal).

The number of such current sensors may also be determined according to at least one of the size, position, and measurement precision of the current to be sensed.

In this example, each current sensor of the current sensor unit 12 may be a current sensor using a Rogowskii coil.

The current sensor using the Rogowski coil integrates and amplifies the output voltage induced by the current flowing in the conductor (that is, the power medium for which the current is to be measured) located inside the circular Rogowski coil made of a nonmagnetic material using an integrating circuit. So the current value can be calculated.

In this case, the Rogowski coil may use a printed circuit board (PCB) Rogoski coil.

In addition, each current sensor of this example may be an air-core coil-type current sensor having a structure for shielding an electric field and a magnetic field that detects a magnetic field generated when a current flows in a conducting wire, and in this case, the accuracy of current measurement is improved.

The temperature sensor unit 13 may also include at least one temperature sensor 131 , 132 , and each temperature sensor 131 , 132 detects the temperature of the mounting position and provides an analog signal (eg, a temperature signal) of the corresponding state. can be printed out.

When the voltage sensor unit 11 includes a voltage sensor using a capacitive method, the dielectric constant of the dielectric provided in the voltage sensor is changed according to the temperature of each voltage sensor.

In addition, a coil used for a current sensor or the like may be mainly made of copper (Cu), and the resistance value of the copper changes according to temperature.

As such, according to the temperature, characteristics of electric and electronic devices used in the voltage current detecting device of the present example, such as a voltage sensor and a current sensor, may change.

Therefore, in order to compensate for a change in characteristics of an electric/electronic device that varies according to temperature, at least one temperature sensor includes an electric/electronic device (eg, a current sensor, a voltage sensor, and an amplifier, etc.) whose characteristics change according to the temperature or its surroundings. It is mounted on the , and may generate a signal (eg, a temperature signal) corresponding to the temperature sensed at the mounting position and output it to the operation control module 40 . Here, the periphery may be referred to as within a set range with respect to the corresponding electrical and electronic device.

In this specification, as an example, the voltage sensor unit 11 includes one voltage sensor to output one voltage signal Vs, and the current sensor unit 12 includes one current sensor to generate one voltage signal Vs. The current signal Is may be output, and the temperature sensor unit 13 includes a first temperature sensor 131 and a second temperature sensor 132 that respectively detect the temperature of the voltage sensor and the current sensor, and each of the first Although it is assumed that the temperature signal Ts1 and the second temperature signal Ts2 are output, the operation of the voltage and current detection device is described, but the present invention is not limited thereto.

The voltage signal amplification unit 21 connected to the voltage sensor unit 11 amplifies the voltage signal (Vs) output from the voltage sensor unit 11 at a set ratio and then uses the amplified voltage signal (Vt) as a voltage signal for measurement. The analog-to-digital conversion unit 40 may output the output.

At this time, the voltage signal amplifying unit 21 amplifies the voltage signal (Vs) output from the voltage sensor so that the magnitude of the voltage signal (Vt) for measurement is included within the set input range of the analog-to-digital converter 40 located at the rear end. can do.

The current signal amplifying unit 22 for measurement and the current signal amplifying unit 23 for protection also amplifies the current signal (Is) output from the current sensor at a set ratio, and converts the amplified current signal (It, Id) to analog-digital It can be output to the unit 40 .

At this time, the current signal amplifying unit 22 for measurement and the current signal amplifying unit 23 for protection are also located at the rear end so that the size of each current signal (It, Id) is included within the set input range of the analog-digital conversion unit 40 It is possible to amplify the current signal output from each current sensor.

The current signal amplifying unit 22 for measurement amplifies the current signal (Is) output from the current sensor within the range of about 1.0 to 1.5 times the normal rating to output the corresponding current signal (It), and a current signal for protection The amplifying unit 23 may amplify the current signal Is output from the current sensor within a range of about 10 to 20 times the normal rating and output the amplified current signal Id.

In this way, the current signal amplifying unit 22 for measurement and the current signal amplifying unit 23 for protection may amplify the same current signal Is using different amplification ratios to each corresponding amplification ratio.

At this time, the amplified current signal (It) output from the current signal amplifying unit for measurement (22) is the final measurement current signal (Itf) output to a measuring device (not shown) that measures the current and voltage of the corresponding power device. It may be a current signal for measurement (It) for, and the amplified current signal (Id) output from the protection current signal amplifying unit 23 is a final protection current signal output to protection equipment (not shown) that protects the corresponding power device It may be a protection current signal (Id) for (Idf).

As described above, since the amplification ratio of the current signal amplification unit 23 for protection is larger than that of the current signal amplification unit 22 for measurement, the protection equipment located at the rear stage is an instantaneous value in each final protection current signal Idf input. value), peak value, and current value at the time of a short circuit can be easily detected, so that the abnormal state of the corresponding power device can be accurately and easily detected, and safety measures such as power-off operation can be taken when an abnormality occurs. can be taken quickly.

The DC component blocking unit 30 is a DC component included in the analog signals (Vt, It, Id) output from the respective amplification units 21-23 and the signals Ts1 and Ts2 output from the temperature sensor unit 13 . In order to remove the DC component, as an example, a high pass filter of 10 Hz to 20 Hz may be used to block the DC component.

1, the DC component blocking unit 30 uses a separate DC component blocking circuit implemented as a circuit to block the DC component included in the analog signals (Vt, It, Id, Ts1, Ts2). However, alternatively, in an alternative example, the direct current component may be implemented in software.

In this case, the DC component blocking unit 30 is implemented as a digital filter whose calculation is performed by the operation of the processor, and after removing the DC component included in each analog signal (Vt, It, Id, Ts1, Ts2), analog-digital It may output to the converter 40 . In this case, the digital filter may be a finite impulse response filter (FIR), an infinite impulse response filter (IIR), or an FFT filter.

However, the DC component blocking unit 30 may be omitted if necessary.

The analog-to-digital conversion unit 40 includes the amplified voltage signal for measurement (Vt) from which the DC component has been removed, the amplified current signal for measurement (It), and the amplified current signal for protection (Id) and each temperature sensor (131, 132). ), the first temperature signal Ts1 and the second temperature signal Ts2 output from the input signal may be respectively received, converted into a digital state having a corresponding value, and outputted to the operation control module 40 .

Accordingly, the analog-to-digital conversion unit 40 synchronizes with the sampling signal applied from the operation control module 40 , the voltage signal for measurement (Vt), the current signal for measurement (It), the current signal for protection (Id), and each By performing a sampling operation on the temperature signal (Ts1, Ts2), sampling data for each signal (Vs, It, Id, Ts2, Ts2) is extracted, quantization is performed on each sampling data, and a decoding operation is performed to Resampling unit 50 by converting the digital data of the number of bits into voltage data for measurement (Vtd), current data for measurement (Itd), current data for protection (Idd), and first and second temperature data (Ts1d, Ts2d) can be output as

Accordingly, the analog-to-digital conversion unit 40 receives the voltage signal for measurement (Vt), the current signal for measurement (It), the current signal for protection (Id) and the temperature signals (Ts1, Ts2) in real time for each cycle of the sampling signal. Generates digital data (Vtd, Itd, Idd, Ts1d, Ts2d) for the corresponding measurement voltage signal (Vt), measurement current signal (It), and protection current signal (Id) at a sampling rate determined according to the sampling signal cycle ) and temperature signals Ts1 and Ts2 can be sampled and converted into digital data.

In this case, each of the data Vtd, Itd, Idd, Ts1d, and Ts2d converted by the analog-to-digital converter 40 may be 16 bits, 24 bits, or 32 bits.

The resampling unit 50 compensates for data lost through a sampling operation performed when an analog signal is converted into a digital signal so that the digital signal waveform has a waveform similar to that of the original signal (Vs, Is, Ts1, Ts1). This is to increase the accuracy of the operation.

The resampling operation of the resampling unit 50 is performed at the same resampling rate as the sampling rate according to the resampling rate, at a resampling rate higher than the sampling rate, or at a resampling rate lower than the sampling rate. cases may exist.

In this case, as the resampling rate is higher than the sampling rate, the similarity with the waveform of the original signal increases, but a distorted portion may occur in the shape of the low-sampling wave.

When resampling is performed in a case where the sampling rate is higher than the sampling rate during analog-to-digital conversion, the resampling unit 50 may use an interpolation method.

That is, when it is higher than the sampling rate during analog-to-digital conversion, the re-sampling unit 50 applies an interpolation method to each of the voltage data for measurement (Vtd), the current data for measurement (Itd), and the current data for protection (Idd). can be obtained to perform the resampling operation.

At this time, the re-sampling unit 50 changes the slope value according to the magnitude of the signal so that the distortion factor of the waveform is the same as or close to the distortion factor of the original signal (VT, IoS, Ts1, Ts2) so as to be as close to the original signal as possible. can Since the interpolation coefficient for this purpose can be already stored in the memory 70 by applying a reference signal and calculating this value during mass production, the resampling unit 50 uses the interpolation coefficient stored in the memory 70 to correspond to the interpolation coefficient. An interpolation operation may be performed on the signals Vtd, Itd, Ts1d, and Ts2d.

As such, after the resampling operation is performed using the interpolation method, the resampling unit 50 corrects the phase of the data generated using the delay filter provided therein, that is, the resampled data, and then the operation control module 60 ) can be printed.

When resampling is performed at the same rate as the sampling rate in analog-to-digital conversion, there is no need to readjust the sampling rate, so the resampling unit 50 uses only a minute delay filter provided therein to measure voltage data (Vtd). ), by delaying each phase of the current data for measurement (Itd) and the current data for protection (Idd), only the phase can be corrected.

Finally, when the next resampling is performed at a rate lower than the sampling rate during analog-to-digital conversion, the resampling unit 50 may use a Gaussian filter.

Accordingly, the resampling unit 50 may filter each of the voltage data for measurement (Vtd), the current data for measurement (Itd), and the current data for protection (Idd) with a Gaussian filter.

At this time, the resampling unit 50 determines a range to take a representative value, and discards a value larger or smaller than a value automatically determined by the resampling unit 50 or a value determined by a user based on the representative value. Therefore, the value of the down-resampled data may be close to the distortion factor of the original signal.

In this way, after the resampling operation is performed using the Gaussian filter, the resampling unit 50 may output the resampled signal to the operation control module 60 after correcting the phase by using a minute delay filter. .

The operation control module 40 is the resampled measurement voltage data (Vtd) applied from the connected resampling unit 50, the resampled measurement current data (Itd), the resampled protection current data (Idd), and The resampled first and second temperature data Ts1d and Ts2d are received.

The operation control module 60 controls the phase of the resampled voltage data for measurement (Vtd) and each of the resampled current data (that is, the resampled current data for measurement (Itd) and the resampled current data for protection (Idd)). may be compared to calculate phase difference data, and the calculated phase difference data may be stored in the memory 70 .

Using the stored phase difference data, the operation control module 60 may correct a phase of at least one of the resampled measurement voltage data Vtd and the resampled current data Itd and Idd.

In addition, the operation control module 60 may perform temperature error correction for the measurement voltage data (Vtd) and the current data (Vtd, Vdd) using the resampled first and second temperature data (Ts1d, Ts2d). have.

In addition, the operation control module 60 uses the amplitude correction value stored in the memory 70 to control at least one of the corresponding data (ie, voltage data for measurement (Vtd) and current data (Itd, Idd)). Amplitude correction can also be performed.

This operation control module 60 will be described in detail next.

The memory 70 may be a storage medium in which data or commands necessary for the operation of the voltage and current detection device are stored.

The memory 70 may store a temperature correction value that is a correction value for a corresponding electrical and electronic device with respect to temperature in the form of a table, and the voltage signal Vs output from the voltage sensor unit 11 and the current sensor unit ( At least one amplitude correction value that is a correction value for the amplitude difference between the current signals Is output in 12) may be set and stored.

In this example, since the temperature sensor includes a first temperature sensor 131 for one voltage sensor and a second temperature sensor 132 for one current sensor, the memory 70 stores voltage data ( The temperature correction value (eg, the first temperature correction value) of Vd) and the temperature correction value (eg, the second temperature correction value) of each current data (Itd and Idd) for the temperature may be stored.

Accordingly, the operation control module 60 uses the first temperature correction value and the second temperature correction value of the memory 70 to check the temperature sensed by the operation of each temperature sensor 131 and 132 and detect the detected temperature. Read each corresponding temperature correction value corresponding to the temperature, and correct the measurement voltage data (Vtd) and current data (ie, measurement current data (Itd) and correction current data (Idd)) output from the corresponding electrical and electronic device can do.

In addition, the memory 70 may store not only the amplitude correction value but also the name of the type of data to be subjected to the amplitude correction, that is, at least one of the voltage data Vd and the current data Itd and Idd. For this reason, the operation control module 60 may perform amplitude correction on the corresponding data using the type of data stored in the memory 70 and an amplitude correction value corresponding thereto.

The digital-to-analog converter 80 includes voltage data for measurement (Vtd'), current data for measurement (Itd'), and protection for measurement in which phase compensation, amplitude compensation, and temperature compensation are made by the operation of the operation control module 60 . The current data Idd' may be respectively converted into a corresponding analog signal and output as a final measurement voltage signal Vtf, a final measurement current signal Itf, and a final protection current signal Idf, respectively.

In this example, the digital signal output from the operation control module 60 may have a step shape due to the quantized digital data.

Accordingly, the digital-to-analog converter 80 of this example may include a smoothing filter or an anti-aliasing filter, and in this case, the waveform of the output signal is supplemented by these filters. can

The final measurement voltage signal Vtf and the final measurement signal Itf in an analog state may be output to the measurement equipment, and the final protection current signal Idf may be output to the protection equipment.

The communication module 90 is connected to the operation control module 60 and is for wireless communication or wired communication with an external device.

Accordingly, the operation control module 60 may transmit the voltage data Ttd' and the current data Itd' and Idd' on which the correction operation has been performed to an external device through the communication module 90 .

In this example, the communication module 90 may use at least one communication method among RS-232, RS-485, CAN, ETHERNET, FIBER OPTIC, and WIFI.

Next, with reference to FIG. 2 , the operation control module 60 will be described in detail.

As shown in FIG. 2 , the operation control module 60 of this example includes a phase comparator 61 , a control unit 62 connected to the phase comparator 61 , a phase comparator 61 , and a control unit 62 . ) may be provided with an oscillation unit 63 connected to.

The phase comparator 61 may generate phase difference data by comparing the phases of the measurement voltage data Vtd applied from the resampling unit 50 and the measurement current data (at least one of Itd and Idd).

At this time, the phase comparator 61 calculates the phase difference between the voltage data for measurement (Vtd) and the current data for measurement (Itd) and between the voltage data for measurement (Vtd) and the current data for protection (Idd) or for measurement A phase difference between the voltage data Vtd and one current data Itd or Idd may be calculated.

In this example, the phase comparator 61 compares the phase difference between the voltage data for measurement (Vtd) and the current data for measurement (Itd) and the phase difference between the voltage data for measurement (Vtd) and the current data for protection (Idd). By calculating all of them, it is possible to generate the corresponding phase difference data.

At this time, the phase difference data between the voltage data for measurement (Vtd) and the current data for measurement (Itd) is called first phase difference data, and the phase difference data between the voltage data for measurement (Vtd) and the current data for protection (Idd) is It may be referred to as second phase difference data.

As shown in FIG. 2 , the control unit 62 may include a control unit 621 and a phase difference correcting unit 622 connected to the control unit 621 ).

The control unit 621 is a part that controls the overall operation of the operation control unit 60 , and may be a processor formed of a chip.

The control unit 621 controls the operation of the phase difference correcting unit 622 and the amplitude correcting unit 423 to control at least one of voltage data for measurement (Vtd), current data for measurement (Itd), and current data for protection (Idd). It is possible to control the operation of correcting the phase of , and using the amplitude correction value stored in the memory 70 , at least one of the voltage data for measurement (Vtd), the current data for measurement (Itd), and the current data for protection (Idd). One amplitude can also be corrected.

The phase difference correcting unit 622 operates under the control of the control unit 621 as described above, and uses the first phase difference data and the second phase difference data to measure voltage data (Vtd), measurement current data (Itd) and At least one phase of the protection current data Idd may be corrected.

In this example, the phase difference correcting unit 622 may correct the phase difference of the corresponding data using a fractional delay filter.

In this way, when the phase difference correction and the amplitude difference correction are performed on at least one of the voltage data for measurement (Vtd), the current data for measurement (Itd), and the current data for protection (Idd), the control unit 621 performs the phase difference correction and the amplitude difference Voltage data for measurement (Vtd'), current data for measurement (Itd'), and current data for correction (Idd') that have been corrected can be generated and output.

The oscillation unit 63 performs an oscillation operation under the control of the control unit 621, generates a sampling signal and a synchronization signal, which are pulse signals having a predetermined fox width, respectively, and outputs the sampling signal to the analog-to-digital conversion unit 40, The synchronization signal may be output to the phase comparator 61 .

The oscillator 63 may include a crystal oscillator.

Next, the operation of the control unit 621 will be described in detail.

First, when the operation of the controller 621 starts, the controller 621 operates the oscillator 63 so that the oscillator 63 generates a sampling signal and a synchronization signal.

Accordingly, the oscillator 63 starts an operation according to the driving signal applied by the controller 621 to generate a sampling signal and a synchronization signal having a predetermined pulse width and frequency, and then performs the analog-to-digital converter 40 and It may output to the phase comparator 61 .

In this way, when a sampling signal is applied from the oscillator 63, the analog-to-digital converter 40 (63) receives a voltage signal (Vt), a current signal (It, Id), and a second input for each cycle of the applied sampling signal. The first and second temperature signals Ts1 and Ts2 may be converted into digital data Vtd, Itd, Idd, Ts1d, and Ts2d, respectively, and applied to the phase comparator 61 and the controller 621 .

Accordingly, the phase comparator 61 calculates the phase difference between the input measurement voltage data Vtd and the measurement current data Itd and the phase difference between the input measurement voltage data Vtd and the protection current data Idd, respectively. Accordingly, first phase difference data and second phase difference data that are phase difference data for each calculated phase difference may be generated and output to the controller 621 .

Accordingly, the controller 621 may store the input first phase difference data and the second phase difference data in the memory 70 , respectively. At this time, the control unit 621 uses the states of the first phase difference data and the second phase difference data to determine which data is delayed among the voltage data for measurement (Vtd), the current data for measurement (Itd), and the current data for protection (Idd). As it is known, information on this may also be stored correspondingly to the first phase difference data and the second phase difference data, respectively.

Also, the controller 621 may store the data V td, Itd, Idd, Ts1d, and Ts2d input from the resampling unit 50 in the memory 70 , respectively.

In this way, when the first phase difference data and the second phase difference data are input from the phase comparison unit 61, the control unit 621 operates the phase difference correcting unit 622 to obtain measurement voltage data (Vtd) and measurement current data ( Itd) and at least one of the protection current data Idd may be corrected for phase difference.

Therefore, the control unit 621 reads the first phase difference data and the second phase difference data, the voltage data for measurement (Vtd), the current data for measurement (Itd), and the current data for protection (Idd) stored in the memory 70 and It may be input to the phase difference corrector 622 .

The phase difference correcting unit 622 calculates the value of at least one of the voltage data for measurement (Vtd) and the current data for measurement (Itd) by using the input first phase difference data to obtain the measurement data (Vtd) and the measurement A phase difference between the current data Itd may be corrected.

In addition, the phase difference correcting unit 622 calculates the value of at least one of the voltage data for measurement (Vtd) and the current data for protection (Idd) using the input second phase difference data to calculate the data for measurement (Vtd) and for protection A phase difference between the current data Idd may be corrected.

As already described, in the memory 70, the delayed data information (Vtd or Itd), which is information of delayed data among the measurement data (Vtd) and the measurement current data (Itd), and the measurement data (Vtd) and the current data for protection ( Idd), since delayed data information (Vtd or Idd), which is information of delayed data, is stored, the controller 621 may output the delayed data information to the phase difference corrector 622 .

Accordingly, the phase difference correcting unit 622 may correct data corresponding to the delayed data information applied from the control unit 621 using the first phase difference data and the second phase difference data, respectively.

By the operation of the phase difference correcting unit 622 , the voltage data for measurement Vtd, the current data for measurement Itd, and the current data for protection Idd may have the same phase without a phase difference.

Unlike this example, in an alternative example, only one phase difference data related to the phase difference between the voltage data for measurement (Vtd) and one current data (Itd or Idd) is calculated, and the subject of phase correction (that is, the delay is When the generated data) is current data, the phases of both the current data for measurement (Itd) and the current data for protection (Idd) may be corrected using one phase difference data.

On the other hand, when only one phase difference data is calculated and the phase correction target is the measurement voltage data (Vtd), of course, the phase of only the measurement voltage data (Vtd) is corrected using the phase difference data, and all data (Vtd, Itd, Idd) can be identically matched.

The phase corrector 622 may correct the phase difference between the corresponding voltage data Vtd and the current data Itd and Idd using a fractional delay filter as described above.

When the phase difference correction using a fractional delay filter is completed, the phase correction unit 622 may input the voltage data Vtd and the current data Itd and Idd for which the phase difference correction is completed to the control unit 621 . . Accordingly, the controller 621 may store the voltage data Vtd and the current data Itd and Idd for which the phase difference correction is completed in the memory 70 .

Next, the controller 621 applies the amplitude correction value to one of the voltage data Vtd and the current data Itd and Idd using the amplitude correction value stored in the memory 70 to obtain the voltage data Vtd and the current Amplitude deviations between the data (Itd and Idd) can be corrected.

At this time, since the amplitude correction target is voltage data Vtd or current data Itd and Idd for which amplitude correction is performed, and is already stored in the memory 70 in correspondence with the amplitude correction value, the controller 621 controls the memory 70 ) and apply the amplitude correction value to the voltage data (Vtd) to correct the amplitude of the voltage data (Vtd) or apply the amplitude correction value to both the current data for measurement (Itd) and the current data for protection (Idd) Thus, the amplitude of the current data Itd and Idd can be corrected.

Next, the control unit 621 controls the temperature correction for the voltage sensor unit 11 and the current sensor unit 12 using the temperature sensed by the first temperature sensor 131 and the second temperature sensor 132 . can

Accordingly, the control unit 621 uses the first temperature data Ts1d related to the temperature of the voltage sensor unit 11 to a temperature correction value corresponding to the first temperature data Ts1d, that is, to the first temperature sensor 131 . The temperature correction value corresponding to the detected temperature is read from the memory 70, and the temperature correction value is calculated on the measurement voltage data (Vt1) for which phase correction and amplitude correction have been completed. ') can be calculated and stored in the memory 70 .

Similarly in the case of the current data (Itd, Idd), the control unit 621 is a temperature correction value corresponding to the second temperature data (Ts2d) related to the temperature of the current sensor unit 12, that is, the second temperature sensor (132) A temperature correction value corresponding to the detected temperature is read from the memory 70 . Then, the control unit 621 calculates the corresponding temperature correction value on each of the current data for measurement (Itd) and the current data for protection (Idd) for which phase correction and amplitude correction are completed, and temperature correction is performed on current data for measurement (Itd') and protection current data Idd' may be calculated and stored in the memory 70 .

As described above, the method of calculating the corrected voltage data Vtd and the current data Itd and Idd as the corresponding temperature correction value may be adding or subtracting the corresponding temperature correction value. In this example, the temperature correction Although the operation is performed after the phase correction and the amplitude correction have been completed, alternatively, the operation may also be performed before at least one of the phase correction and the amplitude correction is performed.

The order of the phase difference correction control operation, the amplitude correction operation, and the temperature correction operation of the controller 4210 may be changed, and at least one of them may be omitted.

Then, the control unit 621 outputs the voltage data for temperature correction (Vtd') and the current data (Itd', Idd') to the digital-to-analog conversion unit 80 for which the temperature correction is completed, and an analog form having each corresponding waveform. A voltage signal for measurement (Vtf), a current signal for measurement (Itf), and a current signal for protection (Idf) may be generated and outputted to measurement equipment and protection equipment, respectively.

The technical features disclosed in each embodiment of the present invention are not limited only to the corresponding embodiment, and unless they are mutually incompatible, the technical features disclosed in each embodiment may be combined and applied to different embodiments.

In the above, embodiments of the present invention have been described. The present invention is not limited to the above-described embodiments and the accompanying drawings, and various modifications and variations will be possible from the point of view of those of ordinary skill in the art to which the present invention pertains. Accordingly, the scope of the present invention should be defined not only by the claims of the present specification, but also by those claims and their equivalents.

11: voltage sensor unit 12: current sensor unit
13: temperature sensor unit 21: voltage signal amplification unit
22: current signal amplification unit for measurement 23: current signal amplification unit for protection
30: DC component blocking unit 40: analog-digital conversion unit
6: motion control module 61: phase comparator
62: control unit 621: control unit
622: phase difference correcting unit 63: oscillation unit
70: memory 80: digital analog-conversion unit
Vs: voltage signal Is: current signal
Ts1: first temperature signal Ts2: second temperature signal
Vt: Voltage signal for measurement It: Current signal for measurement
Id: voltage signal for protection Vtd: resampled voltage data for measurement
Vtd: Resampled current data for measurement Idd: Resampled current data for protection
Ts1d: resampled first temperature data Ts2d: resampled second temperature data
Vtf: Voltage signal for final measurement Itf: Current signal for final measurement
Idf: current signal for final protection

Claims (6)

a voltage sensor that detects a voltage and outputs a voltage signal;
a current sensor that detects a current and outputs a current signal;
a voltage signal amplifier connected to the voltage sensor, amplifying the voltage signal output from the voltage sensor and outputting it as a voltage signal for measurement;
a current signal amplifying unit for measurement connected to the current sensor, amplifying the current signal output from the current sensor and outputting it as a current signal for measurement;
It is connected to the voltage signal amplifier and the current signal amplifier for measurement, and samples the voltage signal for measurement and the current signal for measurement according to a sampling ratio determined by the sampling signal, and converts it into digital data to obtain measurement voltage data and an analog-to-digital converter for generating measurement current data;
a resampling unit connected to the analog-to-digital converter and re-sampling and outputting the voltage data for measurement and the current data for measurement according to a resampling rate determined based on the sampling rate; and
It is connected to the resampling unit, outputs the sampling signal to the analog-digital converter, and compares the phases of the resampled voltage data for measurement and the resampled current data for measurement to calculate phase difference data, for measurement Motion control module that corrects and outputs the phase of voltage data or current data
A voltage and current detection device comprising a. According to claim 1,
The resampling unit,
If the sampling rate and the resampling rate are the same, each phase of the voltage data for measurement and the current data for measurement is delayed using a minute delay filter,
When the re-sampling rate is higher than the sampling rate, the interpolation method is applied to each of the measurement voltage data and the measurement current data to obtain data, perform a resampling operation, and then use a minute delay filter to correct the phase carried out,
When the re-sampling rate is lower than the sampling rate, the voltage and current detection apparatus for measuring the voltage and current data for measurement using a Gaussian filter, respectively, and then performing phase correction using a minute delay filter. In claim 1,
The operation control module,
a phase comparator operating according to a synchronization signal to compare phases of the resampled measurement voltage and the resampled measurement current to output phase difference data;
a memory for storing delayed data information, which is information of an amplitude correction target, an amplitude correction value, and delayed data among the resampled measurement data and the resampled current data for measurement;
It is connected to the phase comparator and corrects the phase of the resampled measurement voltage data or the resampled current data corresponding to the delayed data information using the phase difference data applied from the phase comparator, and the resampling Corrects the phase of the measured voltage data or re-sampled current data, and corrects the amplitude of the re-sampled voltage data or re-sampled current data using the amplitude correction target and the amplitude correction value stored in the memory a control unit; and
An oscillator that operates under the control of the control unit to generate a synchronization signal and a sampling signal, and output them to the analog-to-digital converter and the phase comparator, respectively
A voltage and current detection device comprising a. According to claim 1,
Voltage current further comprising a DC component blocking unit outputting to the analog-to-digital conversion unit by blocking the DC components of the voltage signal for measurement and the current signal for measurement output from the voltage signal amplifying unit and the current signal amplifying unit for measurement detection device. According to claim 1,
The voltage current detection device further comprising a digital-analog converter connected to the operation control module and outputting the corrected voltage data for measurement and the current data for measurement output from the operation control module by converting them into analog signals, respectively. According to claim 1,
a first temperature sensor positioned adjacent to the voltage sensor to sense a temperature of the voltage sensor and output a first temperature signal to the analog-to-digital converter; and
A second temperature sensor positioned adjacent to the current sensor to sense the temperature of the current sensor and output a second temperature signal to the analog-to-digital converter
further comprising,
The analog-to-digital converter converts the first temperature signal and the second temperature signal into digital data, respectively, and outputs the first temperature data and the second temperature data to the resampling unit,
The resampling unit resamples the first temperature data and the second temperature data according to a resampling rate determined based on the sampling rate and outputs the resampling to the operation control module,
The operation control module calculates a temperature correction value corresponding to the first temperature data on the measurement voltage data that is a phase correction, and performs temperature correction on the measurement voltage data that is a phase correction, and the second temperature data A voltage-current detecting device for performing temperature correction of the measured current data, which is phase-corrected, by calculating a temperature correction value corresponding to ?

Images