CN203811718U - Intelligent diagnostic instrument of energy saving of special-line user - Google Patents
Intelligent diagnostic instrument of energy saving of special-line user Download PDFInfo
- Publication number
- CN203811718U CN203811718U CN201420210383.0U CN201420210383U CN203811718U CN 203811718 U CN203811718 U CN 203811718U CN 201420210383 U CN201420210383 U CN 201420210383U CN 203811718 U CN203811718 U CN 203811718U
- Authority
- CN
- China
- Prior art keywords
- circuit
- unit
- chip
- dsp
- peripheral
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000005070 sampling Methods 0.000 claims abstract description 81
- 230000002093 peripheral effect Effects 0.000 claims abstract description 59
- 238000012545 processing Methods 0.000 claims abstract description 37
- 230000003993 interaction Effects 0.000 claims abstract description 22
- 230000001360 synchronised effect Effects 0.000 claims abstract description 11
- 238000007405 data analysis Methods 0.000 claims description 43
- 238000004134 energy conservation Methods 0.000 claims description 37
- 238000004891 communication Methods 0.000 claims description 22
- 230000003139 buffering effect Effects 0.000 claims description 19
- 230000003321 amplification Effects 0.000 claims description 15
- 238000003199 nucleic acid amplification method Methods 0.000 claims description 15
- 238000003860 storage Methods 0.000 claims description 15
- 239000004973 liquid crystal related substance Substances 0.000 claims description 3
- 230000003068 static effect Effects 0.000 claims description 3
- 238000005259 measurement Methods 0.000 abstract description 7
- 238000001514 detection method Methods 0.000 abstract description 6
- 230000003750 conditioning effect Effects 0.000 abstract description 4
- 238000005516 engineering process Methods 0.000 abstract description 4
- 238000000034 method Methods 0.000 description 13
- 238000012544 monitoring process Methods 0.000 description 13
- 238000004458 analytical method Methods 0.000 description 11
- 238000001914 filtration Methods 0.000 description 10
- 230000008569 process Effects 0.000 description 10
- 238000006243 chemical reaction Methods 0.000 description 9
- 230000006870 function Effects 0.000 description 8
- 230000005540 biological transmission Effects 0.000 description 7
- 238000010205 computational analysis Methods 0.000 description 7
- 238000003745 diagnosis Methods 0.000 description 7
- 230000008859 change Effects 0.000 description 6
- 230000004075 alteration Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- 230000005611 electricity Effects 0.000 description 5
- 238000007726 management method Methods 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 238000012550 audit Methods 0.000 description 3
- 238000004422 calculation algorithm Methods 0.000 description 3
- 238000013500 data storage Methods 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 239000003921 oil Substances 0.000 description 2
- 238000004064 recycling Methods 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 241001269238 Data Species 0.000 description 1
- 238000003556 assay Methods 0.000 description 1
- 238000009412 basement excavation Methods 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 238000013480 data collection Methods 0.000 description 1
- 238000013523 data management Methods 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 230000009897 systematic effect Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 230000003442 weekly effect Effects 0.000 description 1
Abstract
The utility model provides an intelligent diagnostic instrument of energy saving of a special-line user. The intelligent diagnostic instrument of energy saving of the special-line user includes a three-phase voltage and current signal sensing unit, a synchronous sampling signal unit, a signal conditioning unit, an A/D sampling unit, a DSP core processing unit, a CPLD and peripheral human-computer interaction unit, and a peripheral interface unit. The three-phase voltage and current signal sensing unit, the signal conditioning unit, the A/D sampling unit, the DSP core processing unit, the CPLD and peripheral human-computer interaction unit are sequentially connected. Based on the latest DSP technology, the intelligent diagnostic instrument enables the data processing to be rapid and accurate, adopts a scientific detection means, and overcomes shortcomings of slow, incomplete and inaccurate sampling data fundamentally. The intelligent diagnostic instrument is characterized by simple operation, portability, low cost, high intelligence, high measurement precision and good anti-interference capability, etc., and is of certain innovativeness in the field of diagnostic apparatuses of energy saving.
Description
Affiliated technical field
The utility model relates to individual line subscriber energy-saving potential diagnostic equipment, particularly relates to the energy-conservation intelligent diagnosing instrument of a kind of individual line subscriber.
Background technology
Since China enters 21st century, welcome one and built the high-speed development period of developing, China GDP in 2010 exceedes Japan becomes the world's second-biggest economy, within 2011, China is by means of consuming then 22.65 hundred million tons of standard oils, 21.7 hundred million tons of standard oils that exceed the U.S. become global first energy state, but China's per Unit GDP Energy Consumption is still three times of left and right of world average level, in the world in very backward position.Occur after global energy crisis from 20 century 70s, countries in the world government starts to recognize the importance of the energy, and a lot of countries have set up oneself energy saving policy and audit plan.It is a kind of professional audit activities, be audit unit according to the relevant energy-saving act of country and standard, to physical process and the financial process of enterprise and other energy unit energy utilization test, verification and assay.
Diagnosis of energy saving is as the tentative diagnosis for business electrical situation and energy conservation potential excavation in energy auditing, can better judge that enterprise produces power consumption, enterprise's energy conservation potential is excavated, the use of scientific and reasonable configuration consumer, improve the electricity consumption service efficiency of consumer, the electricity of avoiding waste, particularly large-scale current consuming apparatus, by certain diagnostic measures, rationally, scientifically drop into and use, focus on the target such as power quality and Electrical Safety, this is significant for enterprise simultaneously.
The distribution system of user side inside generally lacks on-line monitoring system, even if there is on-line monitoring system, but exist deficiency in technology aspect power quality data collection, storage and analysis, still special developed the energy-conservation intelligent diagnosing instrument of individual line subscriber based on TMS320F2812.This instrument " plug and play ", can at least store a weekly data, under the condition not having a power failure user, the electricity consumption situation to all kinds of large users and the quality of power supply can be implemented on-line monitoring and data recording effectively.
Utility model content
Based on this, in order to record quickly and accurately the electric energy service condition of actual individual line subscriber, and provide rational measure and suggestion for actual power use and configuring condition, make individual line subscriber accomplish to maximize production energy-saving, therefore, the utility model provides a kind of individual line subscriber energy-conservation intelligent diagnosing instrument.
The energy-conservation intelligent diagnosing instrument of a kind of individual line subscriber, comprising: three-phase voltage current sensing unit, synchronizing signal sampling unit, signal condition unit, A/D sampling unit, DSP core processing unit, CPLD and peripheral man-machine interaction unit and peripheral interface units;
Described three-phase voltage current sensing unit, signal condition unit, A/D sampling unit, DSP core processing unit, CPLD and peripheral man-machine interaction unit thereof connect successively;
Described synchronous sampling signal unit is connected between described three-phase voltage current sensing unit and A/D sampling unit;
Described peripheral interface units is connected between described DSP core processing unit and CPLD and peripheral man-machine interaction unit thereof;
Described three-phase voltage current sensing unit is connected to individual line subscriber circuit to be measured.
Further, three-phase voltage current sensing unit comprises: electric current and voltage collector, Hall element, magnifier and control switching circuit, and wherein electric current and voltage collector comprises current clamp and voltage clamp two parts;
Described electric current and voltage collector, Hall element, magnifier connect successively, and are connected on the bandwidth-limited circuit in signal condition unit;
Described electric current and voltage collector is connected to individual line subscriber circuit to be measured;
Described control switching circuit is connected between the DSP data analysis chip and magnifier of described DSP core processing unit;
Further, the DSP data analysis chip of described DSP core processing unit is connected on described magnifier by control switching circuit.
Further, described synchronizing signal sampling unit comprises: the zero passage comparator circuit and the Phase Locked Loop Synchronization frequency multiplier circuit that connect according to this;
Described zero passage comparator circuit is connected between described magnifier and Phase Locked Loop Synchronization frequency multiplier circuit;
Described Phase Locked Loop Synchronization frequency multiplier circuit is connected to the MAX1324 chip main circuit of described A/D sampling unit.
Further, described zero passage comparator circuit is mainly made up of CD4052 chip, OPA4227 chip and peripheral circuit thereof, and is connected to frequency multiplication of phase locked loop circuit.
Further, described signal condition unit comprises: the bandwidth-limited circuit, operational amplification circuit and the signal buffer circuit that connect successively;
Described bandwidth-limited circuit is connected between the magnifier and described operational amplification circuit of described three-phase voltage current sensing unit;
Described signal buffer circuit is connected on the MAX1324 chip main circuit of described A/D sampling unit.
Further, described DSP core processing unit comprises: DSP data analysis chip, DSP peripheral circuit, FLASH and extend out RAM.
Described DSP data analysis chip is connected between described A/D sampling unit and described DSP peripheral circuit;
Described DSP peripheral circuit is connected in the CPLD data buffering module of described CPLD and peripheral man-machine interaction unit thereof;
Described FLASH, extend out RAM and be connected between described DSP peripheral circuit and the memory module of described CPLD and peripheral man-machine interaction unit thereof.
Further, described DSP data analysis chip is TMS320F2812 chip, is connected to DSP peripheral circuit, FLASH and extends out RAM circuit;
The described RAM that extends out adopts IS61LV25616 static RAM (SRAM) storage chip, is connected to SST39VF800 chip, and is jointly connected to described DSP data analysis chip.
Further, described CPLD and peripheral man-machine interaction unit thereof, comprise CPLD data buffering module, communication module, memory module, display screen and keyboard;
Described CPLD data buffering module is made up of large scale integrated chip EPM3256SQC144 element, by DSP2812 chip and communication module, memory module, display module and four module slitless connections of keyboard input module;
Described communication module adopts wire communication and two kinds of modes of GPRS wireless telecommunications of RS232 and RS485;
Described memory module is mainly made up of CH376 control and management chip and peripheral circuit thereof, SD draw-in groove, usb circuit etc., wherein SD draw-in groove is connected to CH376 control and management chip, and CH376 control and management chip and peripheral circuit thereof are connected to MAX1324 chip and peripheral circuit thereof;
Described display module adopts LCD12864 Liquid Crystal Module, is connected to 74LVC16245 chip and peripheral circuit thereof;
Described keyboard adopts button trigger circuit, is connected between LCD12864 display screen and DSP data analysis chip.
Further, described peripheral interface units comprises SD card interface, USB interface, RS-232 interface and DC+5V interface.
This instrument has following advantage:
First, the every data of high-precision monitoring, comprising parameters of electric power such as voltage, electric current, power factor (PF), active power, reactive power, applied power, voltage deviation, frequency departure, fundamental power factor, imbalance of three-phase voltage, three-phase current unbalance, each electric current and voltage harmonic content, each harmonic aberration rate, harmonic waves, for energy auditing provides accurate, detailed data, also to solving having great importance for measure of power quality problem.
The second, adopt MAX1324 chip as AD sampled data chip, measuring accuracy is high, and slewing rate speed is high, and greatly reduced switching time, and has reduced the complexity of AD conversion chip hardware setting and Software for Design.
Three, cross zero balancing and the phase locking frequency multiplying method of sampling, can eliminate asynchronous sampling and the impact of period measurement error on measuring accuracy.
Four, consider chip type selecting from cost control and system optimization, make full use of peripheral hardware resource, make system brief efficient, thereby make this installation cost low.
The 5th, storage mode can be with USB flash disk or SD card, flexible and changeable, and removable, capacity storage greatly.Can make like this copy of data more convenient, for monitored data, can carry out local analysis by this diagnostic equipment, and realize long data recording function simultaneously, thereby be more conducive to individual line subscriber electricity consumption situation to carry out science, rationally diagnosis, accomplish to maximize production energy-saving.
Brief description of the drawings
Fig. 1 is the structural representation of the individual line subscriber energy-conservation intelligent diagnosing instrument of the utility model based on TMS320F2812;
Fig. 2 is the structural representation of the energy-conservation intelligent diagnosing instrument of individual line subscriber based on TMS320F2812 of an embodiment;
Fig. 3 is the structural representation of the energy-conservation intelligent diagnosing instrument of individual line subscriber based on TMS320F2812 of an application example;
Fig. 4 is the diagnosis operational flow diagram of the energy-conservation intelligent diagnosing instrument of individual line subscriber based on TMS320F2812 of the present utility model;
Fig. 5 is DSP master routine, signal sampling and the data computational analysis main program flow chart of the energy-conservation intelligent diagnosing instrument of individual line subscriber based on TMS320F2812 of the present utility model;
Fig. 6 is the SD card read/write circuit figure of the energy-conservation intelligent diagnosing instrument of individual line subscriber based on TMS320F2812 of the present utility model;
Fig. 7 is the USB flash disk read/write circuit figure of the energy-conservation intelligent diagnosing instrument of individual line subscriber based on TMS320F2812 of the present utility model.
Embodiment
Below in conjunction with accompanying drawing, the embodiment of the energy-conservation intelligent diagnosing instrument of individual line subscriber based on TMS320F2812 of the present utility model is described in detail.
Fig. 1 is the structural representation of the energy-conservation intelligent diagnosing instrument of individual line subscriber based on TMS320F2812 of the present utility model, comprising: three-phase voltage current sensing unit, signal condition unit, synchronizing signal sampling unit, A/D sampling unit, DSP core processing unit, CPLD and peripheral man-machine interaction unit and peripheral interface units.
Wherein, three-phase voltage current sensing unit, signal condition unit, A/D sampling unit, DSP core processing unit, CPLD and peripheral man-machine interaction unit thereof connect successively; Three-phase voltage current sensing unit is connected to individual line subscriber circuit to be measured; Synchronous sampling signal unit is connected between three-phase voltage current sensing unit and A/D sampling unit; Peripheral interface units is connected with DSP core processing unit and CPLD and peripheral man-machine interaction unit thereof respectively.
The energy-conservation intelligent diagnosing instrument of the above-mentioned individual line subscriber based on TMS320F2812, by three-phase voltage current sensing unit to the three-phase voltage on individual line subscriber circuit to be measured, three-phase current signal gathers, and after processing, signal condition unit is delivered to A/D sampling unit, three-phase voltage signal is after synchronous sampling signal cell processing simultaneously, also be delivered to A/D sampling unit, A/D sampling unit sample rate is fast, sampling precision is high, to three-phase voltage after treatment, three-phase current signal carries out after sampling processing, simulating signal becomes digital signal, again digital signal is delivered on DSP core master unit, carry out FFT processing and analysis through DSP acp chip, calculate the various parameters of electric power useful to user, as fundamental frequency and each harmonic amplitude, phase place, fundamental voltage, current effective value, three phases active power, reactive power, applied power and three-phase activity coefficient, three-phase voltage, current distortion rate etc.These useful parameters of electric power are imported to supporting with it diagnosis of energy saving and energy auditing system software, obtain the energy-conservation auditing system report of user, by report analysis, can obtain user's electric energy service condition, configuring condition, and then provide and maximize conservation measures and suggestion to user, so that electricity consumption enterprise maximizes production energy-saving, effectively utilize electric energy, focus on realizing the target such as Electrical Safety and power quality simultaneously.
The DSP technology of this individual line subscriber energy-saving potential intelligent diagnosing instrument based on up-to-date, data analysis fast, accurately, and adopt the detection means of science, high-precision A/D sampling module, fundamentally stop can't detect position, not comprehensive, sampled data is imperfect, out of true, the slow situation of sampling, simultaneously this instrument have simple to operate, can be portable, the advantage such as cost is low, intellectuality is strong, measuring accuracy is high, and antijamming capability is strong.
Shown in Figure 2, Fig. 2 is the structural representation of the energy-conservation intelligent diagnosing instrument of individual line subscriber based on TMS320F2812 of an embodiment.
In an embodiment, described three-phase voltage current sensing unit comprises therein: electric current and voltage collector, Hall element, magnifier and control switching circuit, wherein electric current and voltage collector comprises current clamp and voltage clamp two parts.
Described electric current and voltage collector, Hall element, magnifier connect successively, and are connected in the bandpass filter in signal condition unit;
Described electric current and voltage collector is connected to individual line subscriber circuit to be measured;
Described magnifier is connected to the bandpass filter of A/D sampling unit;
Described control switching circuit is out connected on magnifier by described DSP data analysis chip I/O mouth;
By electric current and voltage collector, this diagnostic equipment is connected on individual line subscriber circuit to be measured, wherein the current clamp in collector clamps on three-phase line, gathers circuit three-phase current signal to be measured; Voltage clamp in collector clips on the bus bar of circuit to be measured, gathers circuit three-phase voltage signal to be measured.Three-phase voltage, three-phase current signal that electric current and voltage collector measures are delivered to magnifier by Hall element CLSM-10mA, after magnifier, send into signal condition unit and carry out filtering, operation amplifier and buffered, simultaneously, three-phase voltage signal is sent to synchronizing signal sampling unit, after zero passage comparator circuit, by Phase Locked Loop Synchronization frequency multiplier circuit carry out automatically, fast tracking lock is sampled, ensure all the time sample frequency by 256 times of survey line frequency.
Instrument amplifier has the high and low power consumption of precision, common-mode rejection ratio is high, working band is wide feature; Adopt the mode of multistage amplification, filtering, to current signal amplify step by step, filtering step by step, effectively suppress the impact of undesired signal and noise, improve sampling precision and high s/n ratio; The order of magnitude of the current signal that control switching circuit can detect according to microprocessor unit, control instrument amplifier switches to corresponding enlargement factor and amplifies, realize range and switch by the change enlargement factor that gains, ensure measure linear degree and the precision of the current signal of each order of magnitude.
In an embodiment, described synchronizing signal sampling unit comprises therein: zero passage comparator circuit and Phase Locked Loop Synchronization frequency multiplier circuit.
Described zero passage comparator circuit is connected between the magnifier and Phase Locked Loop Synchronization frequency multiplier circuit of three-phase voltage current sensing unit;
Described Phase Locked Loop Synchronization frequency multiplier circuit is connected between the MAX1324 chip main circuit of zero passage comparator circuit and A/D sampling unit;
Zero passage comparator circuit compares by three-phase voltage signal and the threshold voltage come in described three-phase voltage current sensing unit, three-phase voltage simulating signal is converted into pulse signal, makes signal there is stronger signal to noise ratio (S/N ratio) and suppress the features such as zero point drift.Based on this, zero cross detection circuit can detect the cycle of institute's slowdown monitoring circuit according to the point of voltage zero-cross, thereby determines the frequency of institute's slowdown monitoring circuit.Recycling phase-locking frequency multiplication circuit forms frequency tracking circuit, the frequency of institute's slowdown monitoring circuit is carried out to synchronizing and frequency doubling 256 times, the frequency-doubled signal obtaining is as the cycle control signal of A/D sampling, realize the sample frequency that gathers 256 points in a power frequency period, and between these 256 points, are synchronous equal interval samplings, for dsp chip below and the FFT operational analysis of peripheral module thereof.This sample mode improves real-time and the reliability of measurement data.
Described frequency multiplication of phase locked loop circuit is made up of CD4046, CD4040, and CD4046 is universal CMOS phase-locked loop intergrated circuit, is made up of linear voltage controlled oscillator, 2 phase comparators and low-pass filter circuit.By the frequency division effect of CD4040 chip, make this frequency multiplication of phase locked loop circuit to carrying out real-time follow-up from zero passage comparator circuit pulse voltage signal out, in the time of measured signal frequency change, circuit automatically, follow the tracks of and quick lock in signal, ensure all the time sample frequency by 256 times of survey line frequency.
In an embodiment, described signal condition unit comprises therein: bandwidth-limited circuit, operational amplification circuit and signal buffer circuit.
Described bandwidth-limited circuit, operational amplification circuit and signal buffer circuit are connected successively;
Described signal buffer circuit is connected with the MAX1324 chip main circuit of described A/D sampling unit.
Signal condition unit is exactly to convert circuit three-phase voltage to be measured, current signal to standard signal that collecting device can be identified by operations such as amplification, filtering, makes it be suitable for the input of A/D converter (ADC).Then, ADC carries out digitizing to simulating signal, and digital signal is delivered to MCU, DSP or other digital devices, for use in the data processing of system.
By three-phase voltage current sensing unit three-phase voltage out, three-phase current signal flows into signal conditioning circuit, first carry out filtering processing through bandwidth-limited circuit, obtain required frequency, amplitude, the voltage and current signal of phase place, then the three-phase voltage current of by operational amplification circuit, three-phase being processed after filtering carries out gain amplification disposal, guarantee the precision that overall data process is analyzed, finally precision being done to enough signals sends into A/D sampling unit by signal buffer circuit and carries out fast, accurately digital-to-analog conversion, the digital signal converting to can and be used for the identification of DSP Main Processor Unit.
In an embodiment, described A/D sampling unit comprises therein: MAX1324 chip main circuit and sampled digital signal buffer circuit.
Described MAX1324 chip main circuit is connected between the signal buffer circuit of described signal condition unit and the sampled digital signal buffer circuit of described A/D sampling unit;
Described sampled digital signal buffer circuit is connected to the DSP data analysis chip of described DSP Main Processor Unit;
Through signal condition unit, three-phase voltage, three-phase current signal is out sent to the MAX1324 chip main circuit of A/D sampling unit; this circuit carries out fast, accurately samples simulating signal; convert digital signal to; this MAX1324 chip is a kind of 14 high-speed parallel A/D; 8 sampling channels, synchronized sampling ADC converter; can provide ± 5V or 0 to+5V simulation discrepancy scope, the overvoltage protection of can provide ± 16.5V, has dynamic perfromance and acquisition precision that switching rate is fast, excellent.After oversampled digital signal buffer circuit buffering, send into DSP Main Processor Unit through MAX1324 chip main circuit digital signal out, carry out analyzing and processing for DSP master chip.
In an embodiment, described DSP core processing unit comprises therein: DSP data analysis chip, DSP data buffer circuit, FLASH and extend out RAM.
The core master chip that described DSP data analysis chip is diagnostic equipment, is connected between described A/D sampling unit and DSP data buffer circuit;
Described DSP data buffer circuit is connected between described DSP data analysis chip and described CPLD data buffering module;
Described FLASH is connected between described DSP data analysis chip and the memory module of described CPLD and peripheral man-machine interaction unit thereof, belongs to a kind of involatile internal memory.Be connected on DSP data analysis chip;
The described RAM of extending out is connected between described DSP data analysis chip and the memory module of described CPLD and peripheral man-machine interaction unit thereof, for the memory size that expands DSP data analysis chip, the data of sampled data and the computational analysis of DSP core processing unit are stored by certain data layout, to be delivered in SD card or USB flash disk, thereby provide data file for its supporting diagnosis of energy saving and energy auditing system software.
This unit comprises DSP data analysis chip, DSP data buffer circuit, FLASH and extends out tetra-parts of RAM.The TMS320F2812 chip that DSP data analysis chip adopts TI company to produce, it is a 32 fixed-point DSP chip for the high-performance controlled, multi-functional, high performance-price ratio, the highest can work under 150MHz.This chip has a large amount of controlled GPIO mouths, and convenient control is connected with peripheral circuit.This chip integration is very high, fast operation, has remarkable digital signal processing capability, is the most frequently used chip platform in Digital Signals field.Meanwhile, data analysis chip TMS 320 F 2812 dsp chip utilizes the choosing of CS sheet to drag down, and the digital signal of A/D sampling A/D chip MAX1324 sample conversion is gathered to the data of 128 in surveyed one-period.These sampled datas can obtain three-phase voltage, three-phase current effective value through data analysis chip TMS 320 F 2812, again to sample collection to three-phase voltage, three-phase current carry out the computing of FFT fast Fourier, can obtain frequency, voltage, amplitude and the phase place of first-harmonic and each harmonic, and the data of each phase active power, reactive power, applied power, power factor and each harmonic aberration rate, resultant distortion rate etc. parameters of electric power.Fast Fourier Transform (FFT) (FFT) is a kind of variation that time-domain signal is changed into frequency-region signal, is in digital signal processing, to be a kind of method of frequent employing to signal analysis.Utilize Fast Fourier Transform (FFT) (FFT) method the first-harmonic of the electric current and voltage of sampling can be separated with each harmonic, and calculate respectively the parameters of electric power value of required fundametal compoment and each harmonic component.
In DSP Main Processor Unit, the FLASH extending out being in addition connected with TMS320F812 chip and extend out RAM storage chip.Wherein extending out FLASH is a kind of involatile internal memory, also can keep muchly data under the condition that there is no electric current supply, and its storage characteristics is equivalent to hard disk.Because the data of DSP computational analysis are huge, just not saying store the total data on institute's survey line road completely, only DSP processes rear data, and the space that ram in slice has been preserved is inadequate.Extend out intactly store data and reading for external unit of RAM storage chip and FLASH storage chip, make the data transmission of dsp chip and synchronous sampling signal module, CPLD and peripheral cell thereof more simple and efficient.
This unit is calculated and is analyzed the three-phase voltage being transmitted into by A/D sampling unit by DSP data analysis chip, three-phase current digital signal, utilize FFT fast Fourier algorithm to calculate the frequency of first-harmonic and each harmonic, voltage, amplitude and phase place, and each phase active power, reactive power, applied power, power factor and each harmonic aberration rate, the data of resultant distortion rate etc. parameters of electric power, wherein algorithm and control program leave in described FLASH, described in being stored in after described DSP data buffer circuit buffer memory, interim sampled data extends out in RAM, to facilitate read-write in SD card or USB flash disk.
In an embodiment, described CPLD and peripheral man-machine interaction unit thereof comprise therein: CPLD data buffering module, display screen, keyboard, memory module and communication module.
Described CPLD data buffering module is the main treatment circuit of CPLD, is connected on DSP data analysis chip and its peripheral circuit;
Described display screen is connected in CPLD data buffering module, for showing the situation of current three-phase power parameter;
Described keyboard load module is connected between CPLD data buffering module and DSP data analysis chip, for manual operation display screen by button trigger circuit;
Described memory module is connected in described CPLD data buffering module, comprises two kinds of storage mediums of SD card and USB flash disk;
Described communication module is connected in CPLD data buffering module, available RS232 and RS485 realize wire communication function, also usable bluetooth module realizes GPRS wireless communication function, for data transmission, is divided into RS232, RS485 wire communication and two kinds of modes of GPRS wireless telecommunications;
CPLD and peripheral cell thereof comprise five main parts, these five parts play important effect for final data storage and demonstration and panel control, wherein CPLD data buffering module is made up of large scale integrated chip EPM3256SQC144 element, there are 110 I/O mouths, logical operation is fast, this element is by DSP2812 chip and communication module, memory module, display module and four module slitless connections of keyboard input module, complete the logic control to above-mentioned four modules, make between DSP2812 chip and above-mentioned four modules data transmission more quick; Display screen adopts LCD12864 display module, this modular belt Chinese word library, and display resolution is high, can form complete Chinese man-machine interaction graphical interfaces; Keyboard input circuit adopts button trigger circuit, utilizes the I/O mouth signal of DSP data analysis chip to control the operation of display screen, and this keyboard load module is connected with CPLD, for input control detecting instrument manually; Memory module is to utilize the FLASH extension storage capacity that extends out, and utilize file management control chip CH376 read-write USP(as USB flash disk) or SD card in file, USB memory device can be stored a large amount of data, make this memory module can store the data volume at least one week, meanwhile, adopt USB memory device can make this instrument there is the function that can plug mobile storage; Communication module adopts UART chip TL16C550, it adopts RS232, RS485 wire communication mode and GPRS wireless communication mode, its major function be for providing reliably between Digital Circuit-terminating Equipment (DCE) and data terminal equipment (DTE), interface service flexibly.Communicate by letter with monitoring equipment by RS232 or RS485 interface, the function of transmission measurement data and Real-Time Monitoring, on-line monitoring is provided.Meanwhile, this data communication facility also can realize with bluetooth module control circuit, makes the data can wireless transmission, improves detection efficiency, saves detection time.
For the energy-conservation intelligent diagnosing instrument of the more clear individual line subscriber based on TMS320F2812 of the present utility model, set forth a preferred embodiment below.
Shown in Figure 3, Fig. 3 is the structural representation of the energy-conservation intelligent diagnosing instrument of individual line subscriber based on TMS320F2812 of an application example.
Three-phase voltage current sensing unit 01 mainly comprises: the current clamp 02, Hall element 03, the magnifier 05 that connect successively; The voltage clamp 03, Hall element 04, the magnifier 05 that connect successively; Be connected to the control switching circuit 06 on magnifier 05.
Current clamp 02 and voltage clamp 03 are connected to individual line subscriber circuit to be measured.Current clamp 02, Hall element 04, magnifier 05 form three-phase current signal sensing circuit, gather the three-phase current signal of circuit to be measured.The voltage clamp 03, Hall element 04, the magnifier 05 that connect successively form three-phase voltage signal sensing circuit, gather the three-phase voltage signal of circuit to be measured.Wherein, Hall element can adopt CLSM-10mA Hall element, and this sensor has the features such as linear output, high precision, high response speed, antijamming capability is strong.Magnifier can adopt INA118 amplifier.Control switching circuit 6 can be made up of SN74LVC4245 chip and CD4051 chip, control a mouthful output control signal by the I/O of DSP data analysis chip 18, simulant electronic switch through SN74LVC4245 chip controls CD4051 switches, to change the proportion resistor value of amplifier in magnifier 05, thereby change the gain enlargement factor of circuit.
Synchronous sampling signal unit 11 mainly comprises: zero passage comparator circuit 12, frequency multiplication of phase locked loop circuit 13.
Zero passage comparator circuit compares by three-phase voltage signal and the threshold voltage come in described three-phase voltage current sensing unit, three-phase voltage simulating signal is converted into pulse signal, makes signal there is stronger signal to noise ratio (S/N ratio) and suppress the features such as zero point drift.Based on this, zero cross detection circuit can detect the cycle of institute's slowdown monitoring circuit according to the point of voltage zero-cross, thereby determines the frequency of institute's slowdown monitoring circuit.Recycling phase-locking frequency multiplication circuit forms frequency tracking circuit, the frequency of institute's slowdown monitoring circuit is carried out to synchronizing and frequency doubling 256 times, the frequency-doubled signal obtaining is as the cycle control signal of A/D sampling, realize the sample frequency that gathers 256 points in a power frequency period, and between these 256 points, are synchronous equal interval samplings, for dsp chip below and the FFT operational analysis of peripheral module thereof.This sample mode improves real-time and the reliability of measurement data.
Described frequency multiplication of phase locked loop circuit is made up of CD4046, CD4040, and CD4046 is universal CMOS phase-locked loop intergrated circuit, is made up of linear voltage controlled oscillator, 2 phase comparators and low-pass filter circuit.By the frequency division effect of CD4040 chip, make this frequency multiplication of phase locked loop circuit to carrying out real-time follow-up from zero passage comparator circuit pulse voltage signal out, in the time of measured signal frequency change, circuit automatically, follow the tracks of and quick lock in signal, ensure all the time sample frequency by 256 times of survey line frequency.
Signal condition unit 07 mainly comprises: bandwidth-limited circuit 08, operational amplification circuit 09 and signal buffer circuit 10.
Signal condition unit 07 converts measured signal to standard signal that collecting device can be identified by operations such as amplification, filtering, makes it be suitable for the input of A/D converter (ADC).Then, ADC carries out digitizing to simulating signal, and digital signal is delivered to MCU, DSP or other digital devices, for use in the data processing of system.
Signal condition unit 07 is to the voltage signal, the current signal that gather, after anti-interference, operational amplifier amplifies etc. processed, after signal buffer circuit 10 bufferings, I/O mouth control A/D sampling unit 14 by DSP data analysis chip 17 carries out ADC processing, feed back to again the output of pwm signal, preferably, the operational amplification circuit 09 in signal condition unit 07 can adopt OPA4227 operational amplifier.
By three-phase voltage current sensing unit three-phase voltage out, three-phase current signal flows into signal conditioning circuit, first carry out filtering processing through bandwidth-limited circuit, obtain required frequency, amplitude, the voltage and current signal of phase place, then the three-phase voltage current of being processed after filtering mutually by operational amplification circuit 09 carries out gain amplification disposal, guarantee the precision that overall data process is analyzed, finally precision being done to enough signals sends into A/D sampling unit by signal buffer circuit and carries out fast, accurately digital-to-analog conversion, the digital signal converting to can and be used for the identification of DSP Main Processor Unit.
A/D sampling unit 14 mainly comprises: MAX1324 sampling A/D chip 15 and sampled signal buffer circuit 32.
This A/D sampling unit adopts MAX1324 sampling A/D chip 15, through signal condition unit 07, three-phase voltage, three-phase current signal is out sent to MAX1324 chip 14 main circuits of A/D sampling unit 14, this circuit carries out fast, accurately samples simulating signal, convert digital signal to, and be transferred in DSP core processing unit 16 by sampled signal buffer circuit 32.This MAX1324 chip 15 is a kind of 14 high-speed parallel A/D; 8 sampling channels, synchronized sampling ADC converter; can provide ± 5V or 0 to+5V simulation discrepancy scope, the overvoltage protection of can provide ± 16.5V, has dynamic perfromance and acquisition precision that switching rate is fast, excellent.After oversampled digital signal buffer circuit buffering, send into DSP Main Processor Unit through MAX1324 chip 15 main circuits digital signal out, carry out analyzing and processing for DSP master chip.
DSP core processing unit 16 mainly comprises: DSP data analysis chip 17, DSP peripheral circuit 18, FLASH storage chip 19 and extend out RAM storage chip 20.
CPLD and peripheral cell 21 thereof mainly comprise: display screen 22, keyboard 23, CPLD data buffering module 24, memory module 25 and communication module 26.
Wherein, DSP data analysis chip 18 is mainly used in the ADC conversion to current signal and voltage signal sampling, output pwm signal and intellectual analysis calculating and processing to sampled data, voltage signal and current signal are sent to DSP data analysis chip 17 and carry out data sampling conversion after gathering, in DSP data analysis chip 17, sampled data are carried out after digital filtering, by fast Fourier (FFT) computing, can obtain the frequency of first-harmonic and each harmonic, voltage, amplitude and phase place, and each phase active power, reactive power, applied power, power factor and each harmonic aberration rate, the data of resultant distortion rate etc. parameters of electric power.Preferably, DSP data analysis chip 17 adopts TMS320F2812 chip, and memory module 25 can adopt LV25616 static RAM (SRAM) storage chip, is connected to SST39VF800 chip, and is jointly connected to DSP data analysis chip; CPLD data buffering module 24 is connected with TMS320F2812 chip 17, is made up of large scale integrated chip EPM3256SQC144 element, has 110 I/O mouths, and logical operation is fast.This element is by TMS320F2812 chip 17 and communication module, memory module, display module, four module slitless connections of keyboard input module, complete the logic control to above-mentioned four modules, make between TMS320F2812 chip and above-mentioned four modules data transmission more quick, strengthened system rejection to disturbance ability; Display screen 22 and keyboard 23, preferably, display screen 22 is LCDs, can adopt LCD12864 to be with full Chinese word library LCD MODULE, show and read the key-press status of keyboard 23 by display screen 22, realize man-machine interaction, display measurement result or preserve relative parameters setting.
Peripheral interface units 27 mainly comprises: SD card is read mouthful (a SD card draw-in groove) 28, USB interface 29, RS-232 interface 30 and DC+5V interface 31.
For the read-write of SD card and USB flash disk read-write, preferably, can adopt the file in moderate management control chip CH376 read-write USB memory device (as USB flash disk) or SD card, USB memory device can store a large amount of data, adopt USB memory device can make this instrument memory capacity greatly increase, make this instrument there is the function that can plug mobile storage simultaneously; For USB interface, can realize USB flash disk read-write capability, the data of read-write DSP data analysis chip 17 computational analysiss and processing; RS-232 interface makes this diagnostic equipment have RS-232 wire communication function; For DC+5V interface 31, by this interface access 5V direct supply, be whole diagnostic equipment power supply, guarantee instrument is normally worked.
Shown in Figure 4, Fig. 4 is the operational flow diagram of the energy-conservation intelligent diagnosing instrument of individual line subscriber based on TMS320F2812 of an embodiment.
The energy-conservation intelligent diagnosing instrument operational scheme of individual line subscriber based on TMS320F2812 of the present utility model is described below:
First after instrument wiring completes, after checking that wiring is correct, start to detect, instrument enters init state, after initialization completes, enter startup measuring state, the diagnostic equipment circuit three-phase voltage to be measured that starts to sample, current signal, if sampled, continue sampling, until sampling finishes, sampled data enters A/D sampling module, carry out ADC conversion, change successful digital signal enter DSP data analysis chip process calculate and analyze, obtain the various valuable parameters of electric power that will use, read and write in SD card or USB flash disk with certain data layout, show by Liquid Crystal Module simultaneously, also can carry out data transmission by data communication module.After pending data is read and write in SD card or USB flash disk, can be by data importing to supporting energy auditing and energy-saving potential systematic analysis software, the report of production diagnosis of energy saving, reflect the power consumption situation of individual line subscriber by report, and improve corresponding rationality measure and suggestion, make user or enterprise maximize production energy-saving.
Shown in Figure 5, Fig. 5 is DSP main program flow chart, signal sampling and the data computational analysis process flow diagram of the energy-conservation intelligent diagnosing instrument of individual line subscriber based on TMS320F2812 of an embodiment.Be described below:
DSP master routine operational flow diagram: detect and start to start, DSP initialization, open interruption simultaneously, functional unit carries out data sampling, completes A/D conversion, sends into DSP and carries out Data Management Analysis, and finally show result.
Signal sampling and data computational analysis process flow diagram: three-phase voltage, current signal collection starts to start, collection signal first carries out preliminary signal condition, then carry out A/D sampling, when A/D conversion, the digital signal converting to is sent into and in DSP, is carried out sampling analysis, sample mode is 256 point samplings, band has been sampled, DSP utilizes fft algorithm to process sampled data, computational analysis obtains fundamental frequency and each harmonic amplitude, phase place, fundamental voltage, current effective value, each phase power, power factor, each harmonic aberration rate, the parameters of electric power such as resultant distortion rate, so far, signal sampling and data process of calculation analysis finish.
Shown in Fig. 6 and Fig. 7, Fig. 6 is the SD card read/write circuit figure of the energy-conservation intelligent diagnosing instrument of individual line subscriber based on TMS320F2812 of an embodiment, and Fig. 7 is the USB flash disk read/write circuit figure of the energy-conservation intelligent diagnosing instrument of individual line subscriber based on TMS320F2812 of an embodiment.
SD card or USB flash disk read-write are large characteristic parts of the energy-conservation intelligent diagnosing instrument of individual line subscriber based on TMS320F2812 of the present utility model, utilize SD card or USB flash disk read-write, greatly expand the data storage capacity of DSP, make the whole instrument can the Coutinuous store measurement data of a week, greatly save Measuring Time, these data store with certain data layout simultaneously, facilitate matched energy saving analysis software to use, and improve energy-saving analysis efficiency.
The above embodiment has only expressed several embodiment of the present utility model, and it describes comparatively concrete and detailed, but can not therefore be interpreted as the restriction to the utility model the scope of the claims.It should be pointed out that for the person of ordinary skill of the art, without departing from the concept of the premise utility, can also make some distortion and improvement, these all belong to protection domain of the present utility model.
Claims (10)
1. the energy-conservation intelligent diagnosing instrument of individual line subscriber, it is characterized in that, comprising: three-phase voltage current sensing unit, synchronizing signal sampling unit, signal condition unit, A/D sampling unit, DSP core processing unit, CPLD and peripheral man-machine interaction unit and peripheral interface units;
Described three-phase voltage current sensing unit, signal condition unit, A/D sampling unit, DSP core processing unit, CPLD and peripheral man-machine interaction unit thereof connect successively;
Described synchronous sampling signal unit is connected between described three-phase voltage current sensing unit and A/D sampling unit;
Described peripheral interface units is connected between described DSP core processing unit and CPLD and peripheral man-machine interaction unit thereof;
Described three-phase voltage current sensing unit is connected to individual line subscriber circuit to be measured.
2. the energy-conservation intelligent diagnosing instrument of individual line subscriber according to claim 1, it is characterized in that, three-phase voltage current sensing unit comprises: electric current and voltage collector, Hall element, magnifier and control switching circuit, and wherein electric current and voltage collector comprises current clamp and voltage clamp two parts;
Described electric current and voltage collector, Hall element, magnifier connect successively, and are connected on the bandwidth-limited circuit in signal condition unit;
Described electric current and voltage collector is connected to individual line subscriber circuit to be measured;
Described control switching circuit is connected between the DSP data analysis chip and magnifier of described DSP core processing unit.
3. the energy-conservation intelligent diagnosing instrument of individual line subscriber according to claim 2, is characterized in that, the DSP data analysis chip of described DSP core processing unit is connected on described magnifier by control switching circuit.
4. the energy-conservation intelligent diagnosing instrument of individual line subscriber according to claim 2, is characterized in that, described synchronizing signal sampling unit comprises: the zero passage comparator circuit and the Phase Locked Loop Synchronization frequency multiplier circuit that connect according to this;
Described zero passage comparator circuit is connected between described magnifier and Phase Locked Loop Synchronization frequency multiplier circuit;
Described Phase Locked Loop Synchronization frequency multiplier circuit is connected to the MAX1324 chip main circuit of described A/D sampling unit.
5. the energy-conservation intelligent diagnosing instrument of individual line subscriber according to claim 4, is characterized in that, described zero passage comparator circuit is mainly made up of CD4052 chip, OPA4227 chip and peripheral circuit thereof, and is connected to frequency multiplication of phase locked loop circuit.
6. the energy-conservation intelligent diagnosing instrument of individual line subscriber according to claim 1, is characterized in that, described signal condition unit comprises: the bandwidth-limited circuit, operational amplification circuit and the signal buffer circuit that connect successively;
Described bandwidth-limited circuit is connected between the magnifier and described operational amplification circuit of described three-phase voltage current sensing unit;
Described signal buffer circuit is connected on the MAX1324 chip main circuit of described A/D sampling unit.
7. the energy-conservation intelligent diagnosing instrument of individual line subscriber according to claim 1, is characterized in that, described DSP core processing unit comprises: DSP data analysis chip, DSP peripheral circuit, FLASH and extend out RAM;
Described DSP data analysis chip is connected between described A/D sampling unit and described DSP peripheral circuit;
Described DSP peripheral circuit is connected in the CPLD data buffering module of described CPLD and peripheral man-machine interaction unit thereof;
Described FLASH, extend out RAM and be connected between described DSP peripheral circuit and the memory module of described CPLD and peripheral man-machine interaction unit thereof.
8. the energy-conservation intelligent diagnosing instrument of individual line subscriber according to claim 7, is characterized in that, described DSP data analysis chip is TMS320F2812 chip, is connected to DSP peripheral circuit, FLASH and extends out RAM circuit;
The described RAM that extends out adopts IS61LV25616 static RAM (SRAM) storage chip, is connected to SST39VF800 chip, and is jointly connected to described DSP data analysis chip.
9. the energy-conservation intelligent diagnosing instrument of individual line subscriber according to claim 1, is characterized in that, described CPLD and peripheral man-machine interaction unit thereof comprise CPLD data buffering module, communication module, memory module, display screen and keyboard;
Described CPLD data buffering module is made up of large scale integrated chip EPM3256SQC144 element, by DSP2812 chip and communication module, memory module, display module and four module slitless connections of keyboard input module;
Described communication module adopts wire communication and two kinds of modes of GPRS wireless telecommunications of RS232 and RS485;
Described memory module is mainly made up of CH376 control and management chip and peripheral circuit thereof, SD draw-in groove, usb circuit etc., wherein SD draw-in groove is connected to CH376 control and management chip, and CH376 control and management chip and peripheral circuit thereof are connected to MAX1324 chip and peripheral circuit thereof;
Described display module adopts LCD12864 Liquid Crystal Module, is connected to 74LVC16245 chip and peripheral circuit thereof;
Described keyboard adopts button trigger circuit, is connected between LCD12864 display screen and DSP data analysis chip.
10. the energy-conservation intelligent diagnosing instrument of individual line subscriber according to claim 1, is characterized in that, described peripheral interface units comprises SD card interface, USB interface, RS-232 interface and DC+5V interface.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420210383.0U CN203811718U (en) | 2014-04-28 | 2014-04-28 | Intelligent diagnostic instrument of energy saving of special-line user |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420210383.0U CN203811718U (en) | 2014-04-28 | 2014-04-28 | Intelligent diagnostic instrument of energy saving of special-line user |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203811718U true CN203811718U (en) | 2014-09-03 |
Family
ID=51450451
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420210383.0U Expired - Lifetime CN203811718U (en) | 2014-04-28 | 2014-04-28 | Intelligent diagnostic instrument of energy saving of special-line user |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203811718U (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105021910A (en) * | 2014-04-28 | 2015-11-04 | 苏州华天国科电力科技有限公司 | Energy-saving intelligent diagnostic instrument for special-line user |
| CN106526379A (en) * | 2016-11-21 | 2017-03-22 | 广西电网有限责任公司电力科学研究院 | Method for implementing power quality test analysis based on wireless sampling |
| CN106680617A (en) * | 2016-11-21 | 2017-05-17 | 广西电网有限责任公司电力科学研究院 | Wireless sampling-based electric energy quality test and analysis device |
| CN107843781A (en) * | 2017-10-20 | 2018-03-27 | 国家电网公司 | Electric energy quality monitoring analysis system |
-
2014
- 2014-04-28 CN CN201420210383.0U patent/CN203811718U/en not_active Expired - Lifetime
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105021910A (en) * | 2014-04-28 | 2015-11-04 | 苏州华天国科电力科技有限公司 | Energy-saving intelligent diagnostic instrument for special-line user |
| CN106526379A (en) * | 2016-11-21 | 2017-03-22 | 广西电网有限责任公司电力科学研究院 | Method for implementing power quality test analysis based on wireless sampling |
| CN106680617A (en) * | 2016-11-21 | 2017-05-17 | 广西电网有限责任公司电力科学研究院 | Wireless sampling-based electric energy quality test and analysis device |
| CN107843781A (en) * | 2017-10-20 | 2018-03-27 | 国家电网公司 | Electric energy quality monitoring analysis system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN201035054Y (en) | Portable electric energy quality monitoring analyzer based on double CPU mode | |
| CN102445620B (en) | Transient power quality detection device and method for the same | |
| CN203299350U (en) | Battery internal resistance on-line measuring instrument | |
| CN202870226U (en) | Electric energy quality analyzer | |
| CN203811718U (en) | Intelligent diagnostic instrument of energy saving of special-line user | |
| CN201035098Y (en) | Power consumer harmonic monitoring statistical device | |
| CN201716409U (en) | On-site testing device for intelligent electric energy meter | |
| CN103487701A (en) | Intelligent system for on-line automatic detection of electricity-saving potential and rapid energy audit | |
| CN203909191U (en) | Electric energy quality analyzing system based on ARM and FPGA | |
| CN105676041A (en) | Double CPU electric energy quality monitoring device based on DSP and ARM | |
| CN101435842A (en) | Multifunctional integrated test system | |
| Qiao et al. | Development of high-precision distributed wireless microseismic acquisition stations | |
| CN206311666U (en) | A kind of energy-conservation detector | |
| CN104297583A (en) | DSP based power quality testing system | |
| CN203965533U (en) | A kind of individual line subscriber energy-saving potential and quality of power supply intelligent diagnosing instrument | |
| CN206531895U (en) | Harmonic measurement device based on DSP and virtual instrument | |
| CN110824217A (en) | Meter zone electricity larceny prevention detection device and electricity larceny prevention analysis method | |
| CN105021910A (en) | Energy-saving intelligent diagnostic instrument for special-line user | |
| CN202453431U (en) | Handheld electric power multifunctional waveform recording analyzer | |
| CN202486308U (en) | Harmonic electric quantity measuring system | |
| CN203587687U (en) | Three-phase multifunctional electric energy meter based on high-grade dual-AVR single-chip microcomputer | |
| CN202453439U (en) | Comprehensive handheld power quality tester | |
| CN202494744U (en) | Device for detecting quality of electric energy | |
| CN105021911A (en) | Intelligent energy-saving potential and electric energy quality diagnostic device for individual line user | |
| CN101957437A (en) | Intermediate-frequency high-magnetic field measuring device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |