CN2091462U - Portable harmonic wave analyzer - Google Patents

Portable harmonic wave analyzer Download PDF

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Publication number
CN2091462U
CN2091462U CN 91213684 CN91213684U CN2091462U CN 2091462 U CN2091462 U CN 2091462U CN 91213684 CN91213684 CN 91213684 CN 91213684 U CN91213684 U CN 91213684U CN 2091462 U CN2091462 U CN 2091462U
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China
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resistance
adopt
meet
ground connection
circuit
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Withdrawn
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CN 91213684
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Chinese (zh)
Inventor
吴震春
周化仁
仇润鹤
赵英林
任子晖
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China University of Mining and Technology CUMT
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China University of Mining and Technology CUMT
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Priority to CN 91213684 priority Critical patent/CN2091462U/en
Publication of CN2091462U publication Critical patent/CN2091462U/en
Withdrawn legal-status Critical Current

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Abstract

The utility model relates to a portable harmonic wave analyzer, comprising an input front end circuit for detected signals, a sampling pulse generator, a sampling maintaining circuit, a modulus converting (A/D) circuit, a single-chip system, a display and printing circuit, etc. The utility model is capable of sampling detected voltage and current signals simultaneously, processing the 128 sampling values of each detected signal with the fast Fourier transform (FFT), and displaying and printing final analytical results, comprising the effective values of various harmonic frequencies, harmonic contents and total harmonic distortion ratio. The utility model has small size, and can be widely used for the real-time harmonic detection in power supply networks.

Description

Portable harmonic wave analyzer
The utility model is to belong to the Intelligent Measurement technical field.
Development and their application on each industrial sector consumer along with Power Electronic Technique, caused increasing rapidly of Harmonious Waves in Power Systems content, make the harmonic pollution of electrical network serious day by day, electric system various device and communication line have been produced deleterious effect.Take to suppress the countermeasure of harmonic wave, the harm that the restriction harmonic pollution causes must measure in real time and analyze the harmonic content or the aberration rate (value) of harmonic source and supply terminals voltage and current.For this reason, some harmonic wave testers have successively been developed both at home and abroad.As: the SXF-1 type digital sample formula harmonic analysis instrument that computing machine factory in Baoding produces, the NOWA-1 type AC network harmonic analysis instrument that Germany makes etc.These surveying instruments because cost an arm and a leg, volume is big, Heavy Weight, use are cumbersome, is difficult to realize that the popularization and application and the scene that is carried to detect in real time.
The purpose of this utility model just provide a kind of novel, be easy to carry, can be in the production scene to degree height that detect in real time, intelligent and the high harmonic analysis instrument of measuring accuracy.
The utility model is made up of measured signal input front end circuit, sampling pulse generator, sampling hold circuit and analog to digital conversion (A/D) circuit, Single Chip Microcomputer (SCM) system, demonstration and print circuit etc.Its principle of work is: with tested continuous time signal f(t) one-period T be divided into N Along ent, once sample second every T/N and to obtain discrete-time signal, obtain the discrete-time signal f(KT/N that represents with limited wordlength through analog to digital conversion (A/D)), these data input Single Chip Microcomputer (SCM) system are carried out the fast fourier transform analyzing and processing, calculate the each harmonic effective value of measured signal, harmonic content, harmonic wave resultant distortion rate, and show and print its analysis result.In the input front end circuit, adopt voltage isolation transformer, electric current isolating transformer; electrical network and this instrument are isolated on electric fully; and can curb the transient impact voltage and the dash current of electrical network; the protection back-end circuit; use high performance analog-digital conversion a/d chip and relevant hardware circuit; adopting advanced single chip microcomputer is CPU (central processing unit), and with compilation high efficiency frequency analysis program of language compilation and instruments monitor program, the hardware that this instrument is adopted is minimum.
The utlity model has voltage, current signal collection analysis ability simultaneously, the one-period of measured signal is divided into 128 sampled points, each channel signal, measurement is all sampled 8 complete cycles of electrical network first-harmonic at every turn, totally 1024 points, and then carry out Data Management Analysis.Have the function of tracker Frequency Synchronization sampling, still can correct analysis in system frequency change ± 5HZ scope.Have self-checking function, can make to detect automatically the concurrent information that is out of order and exists to all internal storage locations of instrument and key hardware circuit.Can real time print and show the analysis result of measured signal with charactron.The utility model volume is little, in light weight, rational in infrastructure, easy to use, and this instrument is imported in the measured signal that can directly voltage transformer (VT) summation current transformer secondary be surveyed.This Instrument measuring precision height can be widely used in the occasion that each power supply grid harmonic wave detects in real time.
Accompanying drawing 1 is a power unit wiring diagram of the present utility model.
Accompanying drawing 2,3 is a principle of work wiring diagram of the present utility model.
Embodiment of the present utility model 1,2,3 describes in conjunction with the accompanying drawings.
The 220V alternating voltage after power transformer step-down, bridge rectifier, three terminal regulator voltage stabilizing, filtering, obtain the required direct-current working volts ± 5V of each circuit of this instrument, ± 12V.
Form measured signal input front end circuit by voltage isolation transformer, electric current isolating transformer, low-pass filter and clamping circuit.Tested voltage signal is through voltage isolation transformer IC 1After, it is exported through resistance R 1Meet amplifier IC 23 ends and pass through capacitor C 1Meet IC 21,2,5 ends.Amplifier IC 2Be LM324.Amplifier IC 23 ends through capacitor C 2Ground connection, IC 2Output 6,7 ends through resistance R 2Send by diode D 1, D 2, stabilivolt W 1, W 2The clamping circuit that constitutes is more respectively through resistance R 14Connect to adopt and protect device IC 103 ends, through resistance R 6Take over zero comparator IC 55 ends.Tested current signal warp and the resistance R that connects 3After meet electric current isolating transformer IC 3, it is exported through resistance R 4Meet amplifier IC 43 ends and pass through capacitor C 3Meet IC 41,2,5 ends.Amplifier IC 4Be LM324.IC 43 ends through capacitor C 4Ground connection, 6,7 ends are exported through resistance R 5Send by diode D 3, D 4, stabilivolt W 3, W 4The clamping circuit that constitutes is again through resistance R 18Connect to adopt and protect device IC 93 ends, amplifier and Resistor-Capacitor Unit constitute active low-pass filter.
By zero-crossing comparator (LM339) IC 5, phaselocked loop (CD404.6) IC 6, frequency divider (CD4020) IC 8, shaping circuit (74LS14) IC 7, resistance R 7～R 13, capacitor C 5, C 6The sampling pulse generator that constitutes.Will be from IC 5The 50HZ sinusoidal signal of 5 ends inputs passed through zero balancing, at IC 52 ends output 50HZ square-wave signal through resistance R 8, R 9After the dividing potential drop, pass through resistance R again 10Connect Phase Lock Loop IC respectively 614 ends, shaping circuit IC 713 ends.IC 54 ends, 12 end ground connection, connecting resistance R between 2 ends and 3 ends 7Phase Lock Loop IC 66 ends and 7 ends between connect capacitor C 5, 5 ends and 8 end ground connection, 11 ends are through resistance R 12Ground connection, connecting resistance R between 13 ends and 9 ends 11, 9 ends are through resistance R 13, capacitor C 6Ground connection, IC 63 termination frequency divider IC 813 ends, IC 64 termination IC 810 ends.Frequency divider IC 88,11 end ground connection, 9 ends output 6, the 4KHZ square-wave signal send channel switch IC 1011 ends, IC 810 ends output 12,8KHZ square-wave signal send IC 71 end.Shaping circuit IC 711 terminations, 12 ends, the 50HZ square-wave signal of 10 ends output send single-chip microcomputer IC through a point 20P1,1 mouthful, IC 72 terminations, 3 ends, sampling pulse 12, the 8KHZ square-wave signal of 4 ends output send A/D converter IC through the b point respectively 1212 ends and through resistance R 22, R 23Send after the dividing potential drop to adopt and protect device IC 9, IC 108 ends separately.IC 75 ends through d point and single-chip microcomputer IC 20P1,3 mouthfuls link to each other IC 76 ends through resistance R 24, pilot lamp L 1Ground connection, this is to be used for judging when error signal is arranged, and lights L 1The effect of sampling pulse generator is to produce and the synchronous sampling pulse of the tested voltage signal of input, frequency is 12.8KHZ, and when frequency input signal changes, pll lock, guarantee permanent for the tested voltage signal frequency of input 256 times of sampling pulse frequency, adopt and protect device the one-period of each measured signal 256 points of sampling.
By sampling holder (LF398) IC 9, IC 10, channel switch (CD4051) IC 11, A/D converter (AD573) IC 12The sampling hold circuit and the analog to digital conversion circuit that constitute.With 256 sampled points in tested voltage, the current signal one-period, through 6, the quick switching of 4KHZ frequency, make 128 sampled values separately in tested voltage, the current signal one-period carry out analog-to-digital conversion, and send Single Chip Microcomputer (SCM) system to deposit by data bus.Here: IC 93 ends be input as the tested current signal of 50HZ, 2 ends are through resistance R 19Ground connection, through resistance R 20Connect 1 end, 6 ends are through capacitor C 8Ground connection, 256 sampled values in each cycle of tested current signal of 5 ends output are through resistance R 21Send IC 1114 ends.IC 103 ends be input as the tested voltage signal of 50HZ, 2 ends are through resistance R 15Ground connection is through resistance R 16Connect 1 end, 6 ends are through capacitor C 7Ground connection, 256 sampled values in each cycle of tested voltage signal of 5 ends output are through resistance R 17Send IC 1113 ends.IC 116,8,9,10 end ground connection, 11 ends inputs be passage inversion frequency 6,4KHZ, the tested voltage of 3 ends output, interior 128 sampled values separately of each cycle of electric current are sent IC through the C point 1214 ends.IC 1217,15 end ground connection, 18 termination single-chip microcomputer IC 20P1,0 mouthful, 20 termination decoding scheme IC 16Y 2End, 8 bit data bring out the data bus that LSB～MSB connects Single Chip Microcomputer (SCM) system, make its control that is subjected to Single Chip Microcomputer (SCM) system, carry out mould～number conversion, data transmission, deposit.
By single-chip microcomputer (8031) IC 20, eight D-latchs (74LS373) IC 13, decoding scheme (74LS138) IC 16, data memory (6264) IC 14, memory under program (2764) IC 15The Single Chip Microcomputer (SCM) system that constitutes is at memory under program IC 15In deposit monitoring, data acquisition, processing, analysis (FFT) and demonstration, the print routine of this instrument, at data memory IC 14In deposit sampled data, intermediate treatment result and ultimate analysis result.Here: IC 161,2,3 ends meet IC respectively 20P2.5, P2.6, P2.7 mouth, IC 16Y 0, Y 1Meet IC respectively 14, IC 17CE end.IC 20Eight bit data line P0.0～P0.7 connect data bus, IC 20P2.0～P2.4 meet IC 14, IC 15High 5 bit address line A 8～A 12, IC 20The PSEN line meet IC 15DE end, IC 20The manual high level reset circuit of 9 terminations, IC 20WR, RD meet IC respectively 14WR, DE and IC 17WR, RD, IC 20ALE meet IC 1311 ends and IC 17ALE(11) end, IC 20P1.3, P1.4, P1.5 mouth respectively through resistance R 26, R 27, R 28And K switch 1, K 2, K 3After connect+5V or ground connection.Be used to the selection that shows and print.IC 13D 0～D 7Connect data bus, Q 0～Q 7Output meets IC 14, IC 15Least-significant byte address wire A 0～A 7IC 14, IC 15D 0～D 7Connect data bus.Like this, single-chip microcomputer carries out automatic data acquisition without any confusion under program curing control, and analyzing and processing (FFT), its ultimate analysis result are sent printing, shown.In addition, also can carry out self check.
Intelligent miniature printer GP-16 directly is articulated on the data bus, is subjected to IC 15Last frequency analysis result is printed in interior programmed control automatically, comprises the each harmonic effective value, harmonic content, harmonic wave resultant distortion rate etc.
By parallel expansion mouthful (8155) IC of programmable 17, buffer/driver (74LS06,74LS07) IC 19, IC 18And 8 display circuits that seven-segment display digital tube LED constitutes, under Single Chip Microcomputer (SCM) system control, show required last frequency analysis result.Here: IC 17AD 0～AD 7Connect data bus (DATA BUS), IC 17Delivery outlet PA 0～PA 7Meet IC 19After, the control utmost point of bright each charactron of contact again.IC 17Delivery outlet PB 0～PB 7Meet IC 18After, its 8 outputs are through resistance R 29～R 36After connect+5V the control utmost point of bright each section of charactron of contact simultaneously.Like this, display circuit can directly show ultimate analysis result's numerical value.

Claims (2)

1, a kind of novel portable harmonic analysis instrument is made up of measured signal input front end circuit, sampling pulse generator, sampling hold circuit and analog to digital conversion (A/D) circuit, Single Chip Microcomputer (SCM) system, demonstration and print circuit etc., it is characterized in that:
A, 220V alternating voltage after power transformer step-down, bridge rectifier, three terminal regulator voltage stabilizing, filtering, obtain the required direct-current working volts ± 5V of each circuit of this instrument, ± 12V;
B, the measured signal input front end circuit of being made up of voltage isolation transformer, electric current isolating transformer, low-pass filter and clamping circuit are through voltage isolation transformer IC with the survey voltage signal 1After, it is exported through resistance R 1Meet amplifier IC 23 ends and pass through capacitor C 1Meet IC 21,2,5 ends, amplifier IC 2With Resistor-Capacitor Unit R 1, C 2Constitute active low-pass filter, IC 23 ends through capacitor C 2Ground connection, IC 2Output 6,7 ends through resistance R 2Send by diode D 1, D 2, stabilivolt W 1, W 2The clamping circuit that constitutes is more respectively through resistance R 14Connect to adopt and protect device IC 103 ends, through resistance R 6Take over zero comparator IC 55 ends; Tested current signal warp and the resistance R that connects 3After meet electric current isolating transformer IC 3, it is exported through resistance R 4Meet amplifier IC 43 ends and pass through capacitor C 3Meet IC 41,2,5 ends, amplifier IC 4With Resistor-Capacitor Unit R 4, C 4Constitute active low-pass filter, IC 43 ends through capacitor C 4Ground connection, 6,7 ends are exported through resistance R 5Send by diode D 3, D 4, stabilivolt W 3, W 4The clamping circuit that constitutes passes through resistance R again 18Connect to adopt and protect device IC 93 ends;
C, by zero-crossing comparator IC 5, Phase Lock Loop IC 6, frequency divider IC 8, shaping circuit IC 7, resistance R 7～R 13, capacitor C 5, C 6The sampling pulse generator that constitutes, IC 54,12 end ground connection, connecting resistance R between 3 ends and 2 ends 7, 2 ends are exported through resistance R 8, R 9After the dividing potential drop, again through resistance R 18Connect Phase Lock Loop IC respectively 614 ends, IC 713 ends; IC 66 ends and 7 ends between connect capacitor C 5, 5 ends and 8 end ground connection, 11 ends are through resistance R 12Ground connection, connecting resistance R between 13 ends and 9 ends 11, 9 ends are through resistance R 13, capacitor C 6Ground connection, 3 termination IC 813 ends, IC 64 ends meet IC respectively 810 ends and IC 71 end; IC 88,11 end ground connection, 9 termination channel switch IC 1111 ends; IC 72 terminations, 3 ends, 11 terminations, 12 ends, 6 ends are through resistance R 24, pilot lamp L 1Ground connection, 10 ends meet single-chip microcomputer IC through a point 20P1,1 mouthful, IC 75 ends meet single-chip microcomputer IC through the d point 20P1,3 mouthfuls, IC 74 ends meet A/D converter IC through the b point respectively 1212 ends and through resistance R 22, R 23Connect after the dividing potential drop to adopt and protect device IC 9, IC 108 ends separately;
D, by sampling holder IC 9, IC 10, channel switch IC 11, A/D converter IC 12The sampling hold circuit and the analog to digital conversion circuit that constitute, IC 92 ends through resistance R 19Ground connection is through resistance R 20Connect 1 end, 6 ends are through capacitor C 8Ground connection, 5 ends are through resistance R 21Meet IC 1114 ends; IC 102 ends through resistance R 15Ground connection is through resistance R 16Connect 1 end, 6 ends are through capacitor C 7Ground connection, 5 ends are through resistance R 17Meet IC 1113 ends; IC 116,8,9,10 end ground connection, 3 ends output meets IC through the C point 1214 ends; IC 1217,15 end ground connection, 18 termination single-chip microcomputer IC 20P1,0 mouthful, IC 1220 termination code translator IC 16Y 2End, 8 bit data output terminal LSB～MSB connect the data bus of Single Chip Microcomputer (SCM) system;
E, by single-chip microcomputer IC 20, eight D-latch IC 13, code translator IC 16, data memory IC 14, memory under program IC 15The Single Chip Microcomputer (SCM) system that constitutes, IC 161,2,3 ends meet IC respectively 20P2.5, P2.6, P2.7 mouth, IC 16Y 0, Y 1Meet IC respectively 14, IC 17CE end, IC 20Eight bit data line P0.0～P0.7 connect data bus, IC 20P2.0～P2.4 meet IC 14, IC 15High 5 bit address line A 8～A 12, IC 20The PSEN line meet IC 15DE end, IC 20The manual high level reset circuit of 9 terminations, IC 20WR, RD meet IC respectively 14WR, DE and IC 17WR, RD the end, IC 20ALE termination IC 1311 ends and IC 17ALE (11) end, IC 20P1,3, P1,4, P1,5 mouthfuls respectively through resistance R 26, R 27, R 28And K switch 1, K 2, K 3After connect+5V or ground connection; IC 13D 0～D 7Connect data bus, Q 0～Q 7Output meets IC 14, IC 15Least-significant byte address wire A 0～A 7IC 14, IC 15D 0～D 7Connect data bus;
F, intelligent miniature printer directly are articulated on the data bus of Single Chip Microcomputer (SCM) system;
G, by the parallel expansion mouthful IC of programmable 17, buffer/driver IC 18, IC 19And 8 display circuits that seven-segment display digital tube LED constitutes, IC 17AD 0～AD 7Connect data bus, delivery outlet PA 0～PA 7Meet IC 19After, the control utmost point of bright each charactron of contact again, delivery outlet PB 0～PB 7Meet IC 18After, its 8 outputs are through resistance R 29～R 36After connect+5V the control utmost point of bright each section of charactron of contact simultaneously.
2, harmonic analysis instrument according to claim 1 is characterized in that: amplifier IC 2, IC 4Be to adopt LM324, zero-crossing comparator IC 5Be to adopt LM339, Phase Lock Loop IC 6Be to adopt CD4046, frequency divider IC 8Be to adopt CD4020 shaping circuit IC 7Be to adopt 74LS14, adopt and protect device IC 9, IC 10Be to adopt LF398, channel switch IC 11Be to adopt CD4051, A/D converter IC 12Be to adopt AD573, single-chip microcomputer IC 20Be to adopt 8031, eight D-latch IC 13Be to adopt 74LS373, code translator IC 16Be to adopt 74LS138, memory under program IC 15Be to adopt 2764, data memory IC 14Be to adopt 6264, the parallel expansion mouth of programmable is to adopt 8155, buffer/driver IC 18, IC 19Be to adopt 74LS06,74LS07.
CN 91213684 1991-05-05 1991-05-05 Portable harmonic wave analyzer Withdrawn CN2091462U (en)

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Application Number Priority Date Filing Date Title
CN 91213684 CN2091462U (en) 1991-05-05 1991-05-05 Portable harmonic wave analyzer

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Application Number Priority Date Filing Date Title
CN 91213684 CN2091462U (en) 1991-05-05 1991-05-05 Portable harmonic wave analyzer

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CN2091462U true CN2091462U (en) 1991-12-25

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1310393C (en) * 2004-04-29 2007-04-11 江苏省电力公司泰州供电公司 Harmonic superscale protecting method in low-voltage reactive compensation
CN100383537C (en) * 2004-05-20 2008-04-23 上海交通大学 Harmonic detecting method based on adaptive neuronal on-line setting
CN100483138C (en) * 2004-12-24 2009-04-29 陈耀钧 Method and system for detecting and analyzing waveform in monocycle
CN100489544C (en) * 2004-07-29 2009-05-20 特克特朗尼克公司 Spectrogram mask trigger
CN102103155A (en) * 2009-12-21 2011-06-22 艾默生网络能源系统北美公司 Numerical control isolation sampling device
CN102214998A (en) * 2010-04-07 2011-10-12 艾默生网络能源系统北美公司 Isolated sampling device for numerical-control LLC (logical link control) series resonance transformation circuit
CN102103157B (en) * 2009-12-21 2013-11-06 艾默生网络能源系统北美公司 Direct voltage isolated sampling device
CN103873023A (en) * 2004-07-19 2014-06-18 特克特朗尼克公司 Realtime power mask trigger
CN105004913A (en) * 2015-07-21 2015-10-28 黎文安 Real-time tracking method for alternating current sampling frequency of electric power system

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1310393C (en) * 2004-04-29 2007-04-11 江苏省电力公司泰州供电公司 Harmonic superscale protecting method in low-voltage reactive compensation
CN100383537C (en) * 2004-05-20 2008-04-23 上海交通大学 Harmonic detecting method based on adaptive neuronal on-line setting
CN103873023A (en) * 2004-07-19 2014-06-18 特克特朗尼克公司 Realtime power mask trigger
CN100489544C (en) * 2004-07-29 2009-05-20 特克特朗尼克公司 Spectrogram mask trigger
CN100483138C (en) * 2004-12-24 2009-04-29 陈耀钧 Method and system for detecting and analyzing waveform in monocycle
CN102103155A (en) * 2009-12-21 2011-06-22 艾默生网络能源系统北美公司 Numerical control isolation sampling device
CN102103157B (en) * 2009-12-21 2013-11-06 艾默生网络能源系统北美公司 Direct voltage isolated sampling device
CN102214998A (en) * 2010-04-07 2011-10-12 艾默生网络能源系统北美公司 Isolated sampling device for numerical-control LLC (logical link control) series resonance transformation circuit
CN102214998B (en) * 2010-04-07 2014-01-29 艾默生网络能源系统北美公司 Isolated sampling device for numerical-control LLC (logical link control) series resonance transformation circuit
CN105004913A (en) * 2015-07-21 2015-10-28 黎文安 Real-time tracking method for alternating current sampling frequency of electric power system

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