CN103499800A - Frequency characteristic detecting system of electronic type voltage transformer - Google Patents
Frequency characteristic detecting system of electronic type voltage transformer Download PDFInfo
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- CN103499800A CN103499800A CN201310406284.XA CN201310406284A CN103499800A CN 103499800 A CN103499800 A CN 103499800A CN 201310406284 A CN201310406284 A CN 201310406284A CN 103499800 A CN103499800 A CN 103499800A
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Abstract
The invention discloses a frequency characteristic detecting system of an electronic type voltage transformer. The frequency characteristic detecting system comprises a frequency conversion power supply, a boosting unit, a high frequency voltage divider, a merging unit and a frequency characteristic detecting unit. The nominal voltage of the output end of the frequency conversion power supply adjusts the voltage amplitude of a power supply through the boosting unit to supply the primary side high voltage U1 used in an experiment to the electronic type voltage transformer to be detected; the primary side high voltage U1 is converted into the low voltage U2 through the high frequency voltage divider, and the low voltage U2 is used as standard source signals of the frequency characteristic detecting unit; the sampling value of the electronic type voltage transformer to be detected is sent to the frequency characteristic detecting unit through the merging unit, and the sampling value is used as detected signals of the frequency characteristic detecting unit. The frequency characteristic detecting system of the electronic type voltage transformer can reliably and perfectly detect the frequency characteristics of the electronic type voltage transformer, and aims to improve the frequency transmission performance of the electronic type voltage transformer and provide the technical guarantee for safe and stable operation of the electronic type voltage transformer.
Description
Technical field
The present invention relates to intelligent grid detection technique field, be specifically related to a kind of frequency characteristic detection system of electronic type voltage transformer.
Background technology
Fast development along with intelligent grid; electronic type voltage transformer (EVT) is widely applied in intelligent grid; undertaking the metering to secondary side by the progress of disease quickly and accurately of electric system primary side voltage; measure; protection; the IED equipment such as failure wave-recording, the quality of its performance directly affects the operation of IED equipment.
Due to, the application of nonlinear-load, flexible AC transmitting system, Power Electronic Technique in intelligent grid, track traffic, the impact of transformer during no-load closing etc., can produce a large amount of harmonic waves in intelligent grid, the voltage levvl of harmonic content and intelligent grid is closely related, and harmonic wave is the component sine waves of one-period electric parameters, comprise the higher hamonic wave that frequency is the fundamental frequency integral multiple, and frequency not fractional harmoni or a harmonic wave of fundamental frequency integral multiple.
Digitalized electrical energy meter directly utilizes the sampled value of EVT transmission to be measured, therefore the accuracy of EVT directly affects the order of accuarcy of measurement result, if it is non-linear that the frequency characteristic of EVT exists, conversion accuracy difference to the each harmonic composition, to make the measured signal distorted, increase the error of metering, particularly take first-harmonic during as measurement standard.At present, the user is more and more higher to the sensitivity of power supply quality, it is an important content that improves the quality of power supply that harmonic wave improves, EVT is basis and the prerequisite that power quality analysis and the quality of power supply are improved to the Measurement accuracy of harmonic wave, at present both at home and abroad, also for the frequency characteristic of EVT, not carrying out special testing scheme and system, is current urgent problem.
Summary of the invention
Technical matters solved by the invention is to overcome in prior art also for the frequency characteristic of EVT, not carry out special testing scheme and system, so that improve the problem of EVT to the Measurement accuracy of harmonic wave.The frequency characteristic detection system of electronic type voltage transformer provided by the invention, the frequency characteristic to electronic type voltage transformer that can be reliably perfect is detected, be intended to improve the frequency progress of disease performance of electronic type voltage transformer, improve the measuring technology of electronic type voltage transformer, for the safe and stable operation of electronic type voltage transformer provides technical guarantee.
In order to achieve the above object, the technical solution adopted in the present invention is:
A kind of frequency characteristic detection system of electronic type voltage transformer, it is characterized in that: comprise variable-frequency power sources, boosting unit, the high frequency voltage divider, merge cells and frequency characteristic detecting unit, the single-phase 220V power supply of the external power frequency of the input end of described variable-frequency power sources, the rated voltage of the output terminal of variable-frequency power sources is regulated the voltage magnitude of power supply by boosting unit, for electronic type voltage transformer to be measured provides test different electric pressure primary side high voltage U1 used, primary side high voltage U1 also is converted into low-voltage U2 by the high frequency voltage divider, standard source signal as the frequency characteristic detecting unit, electronic type voltage transformer to be measured and high frequency voltage divider are connected in parallel on the power output end of boosting unit, the sampled value of electronic type voltage transformer to be measured sends to the frequency characteristic detecting unit by merge cells, measured signal as the frequency characteristic detecting unit.
The frequency characteristic detection system of aforesaid electronic type voltage transformer, it is characterized in that: described merge cells sends to the sampled value of electronic type voltage transformer to be measured to be connected with the frequency characteristic detecting unit by optical fiber interface, adopts IEC61850-9-1 agreement, IEC61850-9-2 agreement or FT3 agreement to send.
The frequency characteristic detection system of aforesaid electronic type voltage transformer, it is characterized in that: described frequency characteristic detecting unit comprises electric pressure converter, the signal condition module, fiber optical transceiver, the FPGA received for digital quantity, synchronization module and PowerPC processor, described electric pressure converter is for receiving the standard source signal, low-voltage U2 is converted into and can gathers voltage U 3, gathering voltage U 3 is connected with the PowerPC processor by the signal condition module, described fiber optical transceiver is for receiving measured signal, and send measured signal to the PowerPC processor by FPGA, described synchronization module is arranged between signal condition module and merge cells, for the control signal conditioning module, merge cells synchronous acquisition standard source signal and measured signal.
The frequency characteristic detection system of aforesaid electronic type voltage transformer is characterized in that: described frequency characteristic detecting unit also comprises man-machine interface, and described man-machine interface is connected with the PowerPC processor.
The frequency characteristic detection system of aforesaid electronic type voltage transformer, it is characterized in that: described man-machine interface comprises high-resolution color LCD display and USB mouse-keyboard, for the graphical drafting that completes data, the demonstration of error parameter and the setting of test parameters.
The frequency characteristic detection system of aforesaid electronic type voltage transformer is characterized in that: be provided with the low-pass filter circuit that cutoff frequency is not less than 20kHz in described signal condition module, and adopt the high-precision adc chip to be gathered, sample frequency is not less than 50kHz.
The frequency characteristic detection system of aforesaid electronic type voltage transformer, it is characterized in that: the amplitude range of the rated voltage of variable-frequency power sources output terminal is 0～250V, frequency range 20～3000Hz, capacity 10KVA, by the primary side high voltage U1 after boosting unit, frequency is constant, amplitude raises, and in rated voltage, has 5 subharmonic and when following, amplitude raises as 10% of rated voltage, there are 6 subharmonic and when above, amplitude raises as 5% of rated voltage in rated voltage.
The frequency characteristic detection system of aforesaid electronic type voltage transformer is characterized in that: the power output end place of described boosting unit is provided with switch CB, before described switch CB is positioned at electronic type voltage transformer to be measured place in parallel with the high frequency voltage divider.
The invention has the beneficial effects as follows: the frequency characteristic detection system of electronic type voltage transformer of the present invention, the frequency characteristic to electronic type voltage transformer that can be reliably perfect is detected, be intended to improve the frequency progress of disease performance of electronic type voltage transformer, improve the measuring technology of electronic type voltage transformer, for the safe and stable operation of electronic type voltage transformer provides technical guarantee, and have the following advantages
1) regulate the high-tension frequency of primary side and amplitude by variable-frequency power sources, reference frequency output is wide, and the frequency characteristic that can comprehensively carry out the electronic type voltage transformer under different harmonic waves detects;
2) the general FT3 interface light communication based on FPGA, can test the electronic type voltage transformer of each type and different purposes, is not limited to a certain fixation principle and fixing producer;
3) frequency characteristic detecting unit self bandwidth, in conjunction with perfect frequency tracking algorithm and windowing fourier algorithm, measuring accuracy is high;
4) by the synchronizeing of synchronization module control criterion source signal and measured signal, the specified phase deviation of electronic type voltage transformer is compensated, eliminated the error effect that the intrinsic parameter of electronic type voltage transformer is brought;
5) conclusion and the parameter of the frequency characteristic detection system of electronic type voltage transformer, for electronic type voltage transformer at electric energy metrical, quality monitoring, the application of the aspects such as harmonic wave control provides strong testing and verification.
The accompanying drawing explanation
Fig. 1 is the system chart of the frequency characteristic detection system of electronic type voltage transformer of the present invention.
Embodiment
Below in conjunction with Figure of description, the present invention is further illustrated.
As shown in Figure 1, a kind of frequency characteristic detection system of electronic type voltage transformer, it is characterized in that: comprise variable-frequency power sources, boosting unit, the high frequency voltage divider, merge cells and frequency characteristic detecting unit, the single-phase 220V power supply of the external power frequency of the input end of described variable-frequency power sources, the rated voltage of the output terminal of variable-frequency power sources, the amplitude range of rated voltage is 0～250V, frequency range 20～3000Hz, capacity 10KVA, rated voltage is regulated the voltage magnitude of power supply by boosting unit, for electronic type voltage transformer to be measured provides test different electric pressure primary side high voltage U1 used, primary side high voltage U1, frequency is constant, amplitude raises, for the metering electronic type voltage transformer, at least apply rated voltage and there are 2 to 13 subharmonic voltages, electric energy quality measurement electronic type voltage transformer, at least apply rated voltage and there are 2 to 50 subharmonic, the GPF (General Protection False electronic type voltage transformer, at least apply rated voltage and there are few 2 to 5 subharmonic, there are 5 subharmonic and when following in rated voltage, by the boosting unit amplitude, raise as 10% of rated voltage, there are 6 subharmonic and when above in rated voltage, by the boosting unit amplitude, raise as 5% of rated voltage, primary side high voltage U1 also is converted into low-voltage U2 by the high frequency voltage divider, standard source signal as the frequency characteristic detecting unit, electronic type voltage transformer to be measured and high frequency voltage divider are connected in parallel on the power output end of boosting unit, the power output end place of boosting unit is provided with switch CB, before switch CB is positioned at electronic type voltage transformer to be measured place in parallel with the high frequency voltage divider, the sampled value of electronic type voltage transformer to be measured sends to the frequency characteristic detecting unit by merge cells, measured signal as the frequency characteristic detecting unit, merge cells sends to the sampled value of electronic type voltage transformer to be measured to be connected with the frequency characteristic detecting unit by optical fiber interface, adopt the IEC61850-9-1 agreement, IEC61850-9-2 agreement or FT3 agreement send.
Described frequency characteristic detecting unit comprises electric pressure converter, the signal condition module, fiber optical transceiver, the FPGA received for digital quantity, synchronization module and PowerPC processor, electric pressure converter is for receiving the standard source signal, low-voltage U2 is converted into and can gathers voltage U 3, gathering voltage U 3 is connected with the PowerPC processor by the signal condition module, fiber optical transceiver is for receiving measured signal, and send measured signal to the PowerPC processor by FPGA, described synchronization module is arranged between signal condition module and merge cells, for the control signal conditioning module, merge cells synchronous acquisition standard source signal and measured signal, wherein in the signal condition module, be provided with the low-pass filter circuit that cutoff frequency is not less than 20kHz, adopt the high-precision adc chip to be gathered, sample frequency is not less than 50kHz, the ADC chip is selected the over-sampling SAR analog to digital converter AD7767 of ADI company, sampling rate is decided to be 50kHz, this ADC chip has outstanding signal to noise ratio (S/N ratio) (SNR), the low temperature drift, wide dynamic range and high DC precision, be highly suitable for the application of wider dynamic range measurement small-signal,
Fiber optical transceiver is selected the AFBR5803 of Agilent company, this fiber optical transceiver meets the optical property requirement of FDDI PMD standard fully, meet FDDI LCF-PMD standard, meet the optical property requirement of ATM 100 Mb/s Physical layers, meet the optical property requirement of IEEE802.3u 100Base-FX version;
Synchronization module sends to signal condition module and merge cells (MU) by the 1pps signal simultaneously, zero clearing when merge cells (MU) counting should occur with each synchronizing pulse, it is 0 that data set counter when once sampling overlaps with synchronizing pulse is answered assignment, pass through fiber optical transceiver, receive the measured signal of merge cells (MU) output, receive in order to reduce timing jitter and the error that link is brought, realize communication interface with FPGA, obtain tested magnitude of voltage Utest, the synchronous signal conditioning module is by sample counter 1pps signal, complete the synchronous processing of standard source signal and measured signal,
The FPGA received for digital quantity, select the XC3S1000 of xilinx company, this FPGA adopts the 90nm semiconductor technology, be used in widely communication, military, electric power, control, consumer electronics, the fields such as automotive electronics, this chip is based on the ultra-large programmable logic chip of SRAM technique, there is embedded X tremeDSP function, equivalent system door up to 1,000,000 is provided, the block SRAM of 432Kbit, the multiplier of 24 18*18, and 175 pairs of abundant interface resources such as difference I/O, there is good capability of sequential control, greatly reduced the additive error that the data receiver link is brought,
The PowerPC processor is selected the MPC8247 embedded microprocessor of Freescale company, and this processor belongs to PowerQUICC II series, comprises a kernel based on PowerPC MPC603e, and a communication process kernel CPM.The double-core design has powerful processing power and higher integrated level, has reduced the composition expense of system, has simplified the design of circuit board, has reduced power consumption.
Described frequency characteristic detecting unit also comprises man-machine interface, described man-machine interface is connected with the PowerPC processor, man-machine interface comprises high-resolution color LCD display and USB mouse-keyboard, for the graphical drafting that completes data, the demonstration of error parameter and the setting of test parameters.
The software platform of frequency characteristic detecting unit adopts embedded real-time operating system Vxworks, this system has good lasting exploitation and extended capability, high performance kernel and friendly User Exploitation environment, support the embedded type CPU on nearly all modern market, it is widely used in and communicates by letter with remarkable real-time with its good reliability, military, aviation, in the high field of the high-quality precision and sophisticated technologies such as space flight and requirement of real-time, as satellite communication, military exercises, trajectory guidance, aircraft navigation etc., 256 task priorities are provided, support the multi-task scheduling of Priority-based preempt-mode, and the scheduling of the time-slotting between the same priority task, adopt ANSI C procedural language to write application program, the real time data that can guarantee to greatest extent system receives and error calculating.In the frequency characteristic detecting unit, take the PowrePC processor as host CPU, carrying out the data of standard source signal and measured signal processes, by frequency tracking algorithm and fourier filter algorithm, obtain fundamental voltage amplitude Uref and the phase place ref of standard source signal, the fundamental voltage amplitude Utest of measured signal and phase place test, thereby obtain, ratio=(Utest – Uref)/Uref, phase differential=(test – ref) – φ r, the specified phase deviation that φ r is electronic type voltage transformer, accuracy class according to electronic type voltage transformer, ratio under different harmonic tests and phase differential are had to index request, the ratio of actual measurement and phase differential and index are compared, thereby show that whether tested electronic type voltage transformer is overproof, be intended to improve the frequency progress of disease performance of electronic type voltage transformer, improve the measuring technology of electronic type voltage transformer, for the safe and stable operation of electronic type voltage transformer provides technical guarantee.
Above demonstration and described ultimate principle of the present invention, principal character and advantage.The technician of the industry should understand; the present invention is not restricted to the described embodiments; that in above-described embodiment and instructions, describes just illustrates principle of the present invention; without departing from the spirit and scope of the present invention; the present invention also has various changes and modifications, and these changes and improvements all fall in the claimed scope of the invention.The claimed scope of the present invention is defined by appending claims and equivalent thereof.
Claims (8)
1. the frequency characteristic detection system of an electronic type voltage transformer, it is characterized in that: comprise variable-frequency power sources, boosting unit, the high frequency voltage divider, merge cells and frequency characteristic detecting unit, the single-phase 220V power supply of the external power frequency of the input end of described variable-frequency power sources, the rated voltage of the output terminal of variable-frequency power sources is regulated the voltage magnitude of power supply by boosting unit, for electronic type voltage transformer to be measured provides test different electric pressure primary side high voltage U1 used, primary side high voltage U1 also is converted into low-voltage U2 by the high frequency voltage divider, standard source signal as the frequency characteristic detecting unit, electronic type voltage transformer to be measured and high frequency voltage divider are connected in parallel on the power output end of boosting unit, the sampled value of electronic type voltage transformer to be measured sends to the frequency characteristic detecting unit by merge cells, measured signal as the frequency characteristic detecting unit.
2. the frequency characteristic detection system of electronic type voltage transformer according to claim 1, it is characterized in that: described merge cells sends to the sampled value of electronic type voltage transformer to be measured to be connected with the frequency characteristic detecting unit by optical fiber interface, adopts IEC61850-9-1 agreement, IEC61850-9-2 agreement or FT3 agreement to send.
3. the frequency characteristic detection system of electronic type voltage transformer according to claim 1, it is characterized in that: described frequency characteristic detecting unit comprises electric pressure converter, the signal condition module, fiber optical transceiver, the FPGA received for digital quantity, synchronization module and PowerPC processor, described electric pressure converter is for receiving the standard source signal, low-voltage U2 is converted into and can gathers voltage U 3, gathering voltage U 3 is connected with the PowerPC processor by the signal condition module, described fiber optical transceiver is for receiving measured signal, and send measured signal to the PowerPC processor by FPGA, described synchronization module is arranged between signal condition module and merge cells, for the control signal conditioning module, merge cells synchronous acquisition standard source signal and measured signal.
4. according to the frequency characteristic detection system of claim 1 or 3 described electronic type voltage transformer, it is characterized in that: described frequency characteristic detecting unit also comprises man-machine interface, and described man-machine interface is connected with the PowerPC processor.
5. the frequency characteristic detection system of electronic type voltage transformer according to claim 4, it is characterized in that: described man-machine interface comprises high-resolution color LCD display and USB mouse-keyboard, for the graphical drafting that completes data, the demonstration of error parameter and the setting of test parameters.
6. the frequency characteristic detection system of electronic type voltage transformer according to claim 3, it is characterized in that: being provided with cutoff frequency in described signal condition module is 20kHz or the above low-pass filter circuit of 20kHz, and adopting the high-precision adc chip to be gathered, sample frequency is 50kHz or more than 50kHz.
7. the frequency characteristic detection system of electronic type voltage transformer according to claim 1, it is characterized in that: the amplitude range of the rated voltage of variable-frequency power sources output terminal is 0～250V, frequency range 20～3000Hz, capacity 10KVA, by the primary side high voltage U1 after boosting unit, frequency is constant, amplitude raises, there are 5 subharmonic and when following in rated voltage, amplitude raises as 10% of rated voltage, there are 6 subharmonic and when above, amplitude raises as 5% of rated voltage in rated voltage.
8. the frequency characteristic detection system of electronic type voltage transformer according to claim 1, it is characterized in that: the power output end place of described boosting unit is provided with switch CB, before described switch CB is positioned at electronic type voltage transformer to be measured place in parallel with the high frequency voltage divider.
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| CN106646092A (en) * | 2016-12-13 | 2017-05-10 | 中国二冶集团有限公司 | Detection method for secondary system of voltage transformer |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN105487034A (en) * | 2016-01-25 | 2016-04-13 | 云南电网有限责任公司电力科学研究院 | 0.05-level electronic transformer verification method and system |
| CN105785183A (en) * | 2016-03-23 | 2016-07-20 | 中国电力科学研究院 | Online self-monitoring system for electronic transformer measurement circuit |
| CN106646092A (en) * | 2016-12-13 | 2017-05-10 | 中国二冶集团有限公司 | Detection method for secondary system of voltage transformer |
| CN107861087A (en) * | 2017-12-07 | 2018-03-30 | 广东电网有限责任公司电力科学研究院 | A kind of closed loop test system of direct current instrument transformer |
| CN108919163A (en) * | 2018-05-25 | 2018-11-30 | 云南电网有限责任公司电力科学研究院 | Electronic current mutual inductor harmonic wave and frequency aliasing characteristic test system and its model |
| CN111121950A (en) * | 2019-12-06 | 2020-05-08 | 武汉航空仪表有限责任公司 | Non-contact frequency detection device |
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