CN201196659Y - Portable electric power quality monitoring instrument - Google Patents
Portable electric power quality monitoring instrument Download PDFInfo
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- CN201196659Y CN201196659Y CNU2008200841420U CN200820084142U CN201196659Y CN 201196659 Y CN201196659 Y CN 201196659Y CN U2008200841420 U CNU2008200841420 U CN U2008200841420U CN 200820084142 U CN200820084142 U CN 200820084142U CN 201196659 Y CN201196659 Y CN 201196659Y
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Abstract
The utility model discloses a portable electric power quality monitoring instrument which comprises a signal sensing conditioning and A/D conversion module, an FPGA module, a DSP system and an ARM embedded type system; the output ends of the signal sensing conditioning and A/D conversion module and the FPGA module are connected to the input end of the DSP system by a double-port RAM; and the output end of the DSP system is connected with the ARM embedded type system. The portable electric power quality monitoring instrument adopts a system structural proposal of combining FPGA, DSP and ARM. The portable electric power quality monitoring instrument adopts a parallel structure of combining FPGA and DSP to realize multichannel high-speed synchronous sampling and data analysis and processing in parallel, adopts FPCA pure hardware to realize multichannel high-speed data acquisition needed by the electric power quality monitoring, fully utilizes the advantages of DSP on high-speed digital computation and adopts a method of combining FFT, continuous wavelet transform and self-adaptive filtering to realize the high-precision analysis and computation of electric power quality parameters in a stable state and a transient state. The portable electric power quality monitoring instrument can comprehensively reflect the situation of actual electric power quality of a monitored object and greatly improve measuring precision.
Description
[technical field]
The utility model relates to electric power quality monitoring technical field, particularly a kind of portable DSP power harmonic monitoring instrument.
[technical background]
The electric power quality is the important indicator of power industry product, relates to generating, power supply, electricity consumption each side investor, operator's rights and interests.Ensure that the electric power quality is electric power enterprise and user's common responsibility and obligation, country has done corresponding requirement in electric power law.The generation of electric power quality problem may derive from the electrical power trans mission/distribution system of supplier of electricity, also may derive from the unreasonable electricity consumption of user side, also may derive from spontaneous phenomenons such as thunder and lightning.Therefore, be necessary to strengthen to the management of electric power quality and carry out the electric power quality monitoring, find out electric power quality problem and reason thereof, and definite accident responsibility side, ensure the legitimate rights and interests of each side.
Along with the development of China's industrial economy growth at full speed, particularly metallurgical industry, electric railway, chemical industry and popularizing of industrial variable-frequency power sources, non-linear, impact load in the electric system increase fast, and the electric power quality problem is on the rise.On the other hand, electric power quality sensitive equipment increases gradually, requires to improve constantly, not only comprise traditional static power Q factor, as mains by harmonics, frequency departure, voltage deviation and three-phase imbalance etc., also comprise voltage swells, rapid drawdown and transient state electric power Q factors such as short supply interruption, transient overvoltage.The electric power quality goes wrong and can make power supply department and power consumer suffer enormous economic loss; the voltage dip of a few tens of milliseconds will cause the waste product of a semiconductor plants millions of dollar; also can cause relay protection mistake jumping, motor burning, transformer is overheated, capacitor is unusual etc., and the safety and economic operation of electric system is caused serious harm.The annual economic loss that causes because of the electric power quality problem is up to 30,000,000,000 dollars.And improve electric system electric power quality, and can reduce the loss of electric power energy on power circuit and equipment, help energy-conservation and environmental protection.
At home, electric power quality monitoring aspect has also obtained certain achievement, and companies such as electricity, Shenzhen neck step, Hefei development, Baoding side head, Shanghai Baosteel An Da all develop some specific products in Shenzhen, comprise hand-held analyzer, remote monitoring instrument.But its major function still is confined to traditional steady state power Q factor monitoring such as voltage deviation, frequency departure, imbalance, harmonic wave, lack the monitoring of transient state electric power Q factor, and the general technical level is still more backward, can not finely satisfy the actual requirement of current power quality monitoring.
External electric power quality monitoring equipment level is generally higher, and of a great variety.But because instrument itself does not have perfect interface, be difficult for being implemented in the on-the site analysis function of each monitoring point, and measuring accuracy is not high enough, price is very expensive high, and promoting at home has certain degree of difficulty.
[summary of the invention]
The purpose of this utility model is exactly in order to solve problems of the prior art, proposes a kind of portable power quality monitoring instrument, can reflect the true electric power quality situation of monitoring target comprehensively, and improves measuring accuracy.
For achieving the above object, the utility model patent has proposed a kind of portable power quality monitoring instrument, comprise sensing conditioning and A/D modular converter, FPGA module, dsp system and ARM embedded system, the output terminal of described sensing conditioning and A/D modular converter and FPGA module all is connected to the input end of dsp system by dual port RAM, the output terminal of dsp system is connected with the ARM embedded system.
As preferably, described sensing conditioning and A/D modular converter comprise that voltage sensor, current sensor, signal conditioning circuit, channel selecting control circuit and band sampling keep 16 8 passage high-speed a/ds of function, the output terminal of described voltage sensor and current sensor is connected to the input end of signal conditioning circuit, the output terminal of signal conditioning circuit is connected respectively to channel selecting control circuit and 16 8 passage high-speed a/ds, and the output terminal of 16 8 passage high-speed a/ds is connected to dual port RAM.
As preferably, described FPGA module comprises that automatic choosing is controlled mutually, robust phaselocked loop and A/D conversion and control and sampled data storage control, the described input end that selects facies-controlled output terminal to be connected to the channel selecting control circuit automatically, robust phaselocked loop and A/D conversion and control are connected between channel selecting control circuit and 16 the 8 passage high-speed a/ds, and sampled data storage control output end is connected to the input end of dual port RAM.
As preferably, carry out exchanges data by the HPI parallel interface between described dsp system and the ARM embedded system.
The beneficial effect of the utility model patent: the utility model adopts the system architecture scheme of FPGA+DSP+ARM.Utilize the FPGA+DSP parallel organization, the multichannel high-speed synchronous sampling of Parallel Implementation is handled with data analysis, adopt the pure hardware of FPGA to realize the multi-channel high-speed data collection that the electric power quality monitoring needs, and made full use of the advantage of DSP on high-speed figure is calculated, the method that adopts FFT, continuous wavelet transform and auto adapted filtering to combine realizes that the high accuracy analysis of stable state and transient state electric power Q factor calculates.The preservation of signals sampling and sampled data realizes that by the FPGA hardware controls speed is fast fully.The electric power attributional analysis calculates then and is realized by an other special high-speed dsp.Carry out data interaction by dual port RAM between the two, finish when gathering current sample window data in FPGA control, high-speed dsp carries out analyzing and processing to last sample window data, parallel processing technique by this data sampling and electric power attributional analysis, eliminated the time interval between two groups of sampled datas, thereby realize uninterruptedly sampling and handle each cycle voltage and current signal of each passage, find the various electric power quality incidents in each cycle.Can reflect the true electric power quality situation of monitoring target comprehensively, improve measuring accuracy greatly, and have advantages such as monitoring parameter is complete, man-machine interface is friendly, data management is convenient, convenient and fast communication.
[description of drawings]
Fig. 1 is the structural representation of the utility model portable power quality monitoring instrument.
[embodiment]
Consult Fig. 1, portable power quality monitoring instrument, comprise sensing conditioning and A/D modular converter 1, FPGA module 2, dsp system 3 and ARM embedded system 4, the output terminal of described sensing conditioning and A/D modular converter 1 and FPGA module 2 all is connected to the input end of dsp system 3 by dual port RAM 5, the output terminal of dsp system 3 is connected with ARM embedded system 4.By the FPGA+DSP parallel system organization, realized the parallel processing of data sampling and electric power attributional analysis, each cycle voltage and current signal of uninterrupted sampling and each passage of analyzing and processing, find the various electric power quality incidents in arbitrary cycle, realize perfect information electric power Quality Detection, thereby reflect the electric power quality truth of monitoring target comprehensively.Adopt this technology can monitor the various randomness electric power quality incidents of finding in the random time, guarantee monitoring target is carried out the overall process on-line real time monitoring.FPGA hardware is realized the sampling of data and is preserved control, high-speed dsp carries out the electric power attributional analysis specially and calculates, comprise FFT, continuous wavelet transform and auto adapted filtering etc., the man-machine interface of system, data communication and data management function are then realized by the ARM embedded system.Three modules have been given full play to intrinsic advantage separately, have realized the needed various functions of electric power quality monitoring device well, satisfy different on-the-spot actual needs.
Described sensing conditioning and A/D modular converter 1 comprise that voltage sensor 11, current sensor 12, signal conditioning circuit 13, channel selecting control circuit 14 and band sampling keep 16 8 passage high-speed a/ds 15 of function, the output terminal of described voltage sensor 11 and current sensor 12 is connected to the input end of signal conditioning circuit 13, the output terminal that the output terminal of signal conditioning circuit 13 is connected respectively to channel selecting control circuit 14 and 15,16 8 passage high-speed a/ds 15 of 16 8 passage high-speed a/ds is connected to dual port RAM 5.Sensing conditioning and 1 pair of voltage of A/D modular converter, electric current electric weight carry out sensing, conditioning and A/D conversion.
Described FPGA module 2 comprises that automatic choosing controls 21 mutually, robust phaselocked loop and A/D conversion and control 22 and sampled data storage control 23, the input end that 21 output terminal is connected to channel selecting control circuit 14 is controlled in described automatic choosing mutually, robust phaselocked loop and A/D conversion and control 22 are connected between channel selecting control circuit 14 and 16 the 8 passage high-speed a/ds 15, and sampled data storage control 23 output terminals are connected to the input end of dual port RAM 5.A kind of robust phase-locked loop systems has been adopted in signal synchronous collection control, and this robust phaselocked loop can effectively obtain the electrical network basic frequency under various complex electric network environment, have very strong robustness.This phase-locked module produces the synchronized sampling control signal, and the conversion chip of 16 8 passage high-speed a/ds 15 is controlled, and realizes the signal Synchronization sampling.This method has better stability, synchronism than conventional phase locked loops technology, guarantees for the electric power quality high accuracy analysis of back provides good prerequisite.FPGA module 2 is mainly finished the signal sampling control and the sampled data storage control of this electric power quality monitoring device.
Carry out exchanges data by the HPI parallel interface between described dsp system 3 and the ARM embedded system 4.High-speed dsp system 3 mainly finishes various electric power attributional analysis computing functions, and the data interaction of FPGA module and dsp system realizes by a dual port RAM.
ARM embedded system module is mainly finished man-machine interface, data management and the correspondence with foreign country of electric power quality monitoring device, realize electric power attributional analysis result's literal and graphical the displaying, data management functions such as data storage and deletion, data query, statistical study, and functions such as data communication such as 232/485 serial ports, USB interface and Ethernet interface, carry out exchanges data by the HPI parallel interface between DSP and the ARM.
On the software configuration, mainly comprise modules compositions such as data acquisition, electric power attributional analysis, electric power quality event classification, data management, data communication and man-machine interface.
1. data acquisition module
Finish the data acquisition of electric weight such as three-phase voltage, three-phase current and neutral point voltage and neutral current, system's counting of ripple sampling weekly is 256 points, realizes that by the VHDL code of FPGA image data is saved in the dual port RAM.
2. electric power attributional analysis module
The main analytical calculation of finishing electric power Q factors such as voltage deviation, frequency departure, voltage fluctuation and flickering, harmonic wave, three-phase imbalance, short supply interruption, voltage swells, rapid drawdown, transient overvoltage according to the data that collect of electric power attributional analysis module.The electric power attributional analysis mainly adopts the through engineering approaches algorithm of FFT and continuous wavelet S conversion and auto adapted filtering to realize.Electric power attributional analysis module realizes in dsp system.
4. electric power quality event classification module
According to electric power attributional analysis result, by extracting feature, obtain the category feature that characterizes variety of event, adopt intellectual technologies such as support vector machine, fuzzy technology to realize presorting of electric power quality incident then, to reduce requirement, provide quicker, assessment and decision information more accurately for the monitor staff at scene simultaneously to memory capacity.
5. data management module
This electric power quality monitoring device embeds on the platform base at ARM and has realized data storage and data management functions such as deletion, data query, statistical study and file management, and electric power attributional analysis result data is managed.
6. data communication module
Design communication interface driver is realized ethernet communication, USB interface and RS232/485 serial communication.The use of many communication modes has made things convenient for the electric power quality monitoring data transmission of different field conditions.
7. human-computer interface module
Utilize ARM+LINUX embedded system gui interface close friend's characteristics, every electric power Q factor of finishing monitored point shows various parameter forms, oscillogram, spectrogram, changing trend diagram etc. galore, can carry out the analysis processing result of various parameters, the output and the printing of statistics form.
Traditional steady state power Q factors such as this equipment not only can overall process on-line monitoring voltage deviation, three-phase imbalance, harmonic wave, but also monitoring voltage rise sharply, transient state electric power Q factor such as rapid drawdown, short supply interruption, transient overvoltage, reflect the true electric power quality situation of monitoring target with this comprehensively.This equipment can be widely used in electric company, generating plant, electricity and build electric power enterprises such as company, and the electric power quality monitoring of industrial circle such as petroleum chemical enterprise, automobile making, electric railroad, subway, steelworks.
The foregoing description is to explanation of the present utility model, is not to qualification of the present utility model, any scheme after the utility model simple transformation is all belonged to protection domain of the present utility model.
Claims (4)
1. portable power quality monitoring instrument, it is characterized in that: comprise sensing conditioning and A/D modular converter (1), FPGA module (2), dsp system (3) and ARM embedded system (4), the output terminal of described sensing conditioning and A/D modular converter (1) and FPGA module (2) all is connected to the input end of dsp system (3) by dual port RAM (5), the output terminal of dsp system (3) is connected with ARM embedded system (4).
2. portable power quality monitoring instrument as claimed in claim 1, it is characterized in that: described sensing conditioning and A/D modular converter (1) comprise voltage sensor (11), current sensor (12), signal conditioning circuit (13), channel selecting control circuit (14) and band sampling keep 16 the 8 passage high-speed a/ds (15) of function, the output terminal of described voltage sensor (11) and current sensor (12) is connected to the input end of signal conditioning circuit (13), the output terminal of signal conditioning circuit (13) is connected respectively to channel selecting control circuit (14) and 16 8 passage high-speed a/ds (15), and the output terminal of 16 8 passage high-speed a/ds (15) is connected to dual port RAM (5).
3. portable power quality monitoring instrument as claimed in claim 2, it is characterized in that: described FPGA module (2) comprises that (21), robust phaselocked loop and A/D conversion and control (22) are controlled in automatic choosing mutually and (23) are controlled in the sampled data storage, the output terminal that (21) are controlled in described automatic choosing mutually is connected to the input end of channel selecting control circuit (14), robust phaselocked loop and A/D conversion and control (22) are connected between channel selecting control circuit (14) and 16 the 8 passage high-speed a/ds (15), and sampled data storage control (23) output terminal is connected to the input end of dual port RAM (5).
4. as claim 1 or 2 or 3 described portable power quality monitoring instrument, it is characterized in that: carry out exchanges data by the HPI parallel interface between described dsp system (3) and the ARM embedded system (4).
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| CNU2008200841420U CN201196659Y (en) | 2008-03-21 | 2008-03-21 | Portable electric power quality monitoring instrument |
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| CNU2008200841420U CN201196659Y (en) | 2008-03-21 | 2008-03-21 | Portable electric power quality monitoring instrument |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103226293A (en) * | 2013-03-26 | 2013-07-31 | 中国科学院光电技术研究所 | High-precision multichannel data acquisition system for focus detection system of photoetching machine |
| WO2014008792A1 (en) * | 2012-07-11 | 2014-01-16 | 福建省电力有限公司电力科学研究院 | Distribution network voltage fluctuation positioning method and device |
| CN103675492A (en) * | 2012-09-07 | 2014-03-26 | 国网电力科学研究院 | Electricity consumption monitoring analysis method, portable electricity consumption monitoring analysis device and system |
| CN105516033A (en) * | 2015-07-23 | 2016-04-20 | 中国电子科技集团公司第四十一研究所 | Analog signal demodulation and analysis method based on spectrum analyzer |
| CN105896523A (en) * | 2015-02-13 | 2016-08-24 | 英飞凌科技股份有限公司 | Dynamically adapting device operations to handle changes in power quality |
| CN107167651A (en) * | 2017-06-19 | 2017-09-15 | 西北大学 | A kind of voltage signal acquisition system and method |
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2008
- 2008-03-21 CN CNU2008200841420U patent/CN201196659Y/en not_active Expired - Fee Related
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2014008792A1 (en) * | 2012-07-11 | 2014-01-16 | 福建省电力有限公司电力科学研究院 | Distribution network voltage fluctuation positioning method and device |
| CN103675492A (en) * | 2012-09-07 | 2014-03-26 | 国网电力科学研究院 | Electricity consumption monitoring analysis method, portable electricity consumption monitoring analysis device and system |
| CN103675492B (en) * | 2012-09-07 | 2016-01-20 | 国家电网公司 | A kind of electricity consumption monitoring analytical approach, portable electricity consumption monitoring analytical equipment and system |
| CN103226293A (en) * | 2013-03-26 | 2013-07-31 | 中国科学院光电技术研究所 | High-precision multichannel data acquisition system for focus detection system of photoetching machine |
| CN105896523A (en) * | 2015-02-13 | 2016-08-24 | 英飞凌科技股份有限公司 | Dynamically adapting device operations to handle changes in power quality |
| CN105896523B (en) * | 2015-02-13 | 2018-11-30 | 英飞凌科技股份有限公司 | The system and method for operation for dynamic adaptation equipment and the system tested for executing operation |
| CN105516033A (en) * | 2015-07-23 | 2016-04-20 | 中国电子科技集团公司第四十一研究所 | Analog signal demodulation and analysis method based on spectrum analyzer |
| US10031500B1 (en) | 2017-03-01 | 2018-07-24 | PLETHORA IIoT, S.L. | Device and system including multiple devices for supervision and control of machines in industrial installation |
| US10317888B2 (en) | 2017-03-01 | 2019-06-11 | PLETHORA IloT, S.L. | Device and system including multiple devices for supervision and control of machines in industrial installation |
| US10860006B2 (en) | 2017-03-01 | 2020-12-08 | Plethora Llot, S.L. | Device and system including multiple devices for supervision and control of machines in industrial installation |
| CN107167651A (en) * | 2017-06-19 | 2017-09-15 | 西北大学 | A kind of voltage signal acquisition system and method |
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Granted publication date: 20090218 Termination date: 20120321 |