CN104950280A - System for detecting abnormal working conditions of current transformer loop - Google Patents
System for detecting abnormal working conditions of current transformer loop Download PDFInfo
- Publication number
- CN104950280A CN104950280A CN201510360024.2A CN201510360024A CN104950280A CN 104950280 A CN104950280 A CN 104950280A CN 201510360024 A CN201510360024 A CN 201510360024A CN 104950280 A CN104950280 A CN 104950280A
- Authority
- CN
- China
- Prior art keywords
- pin
- resistance
- constant
- loop
- forms
- 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.)
- Granted
Links
Landscapes
- Measurement Of Resistance Or Impedance (AREA)
Abstract
The invention discloses a system for detecting abnormal working conditions of a current transformer loop. The system comprises an AC constant-current source and an impedance transformer, wherein an output end of the AC constant-current source is connected with one side of the impedance transformer, and the other side of the impedance transformer is connected with a TA loop; the output end of the AC constant-current source is also connected to an input end of an in-phase proportional amplifier, an output end of the in-phase proportional amplifier is connected with an input end of a band-pass filter, and an output end of the band-pass filter is connected with an input end of a linear rectifier filter. The system has the benefits as follows: the system can monitor the TA loop in real time and reflect failure results timely when the TA loop fails and causes abnormal metering, so that a power consumption management institution can eliminate failures timely; the system can also effectively prevent abnormal power consumption conditions such as electricity stealing and the like to prevent loss of the national benefit; besides, the detection system is low in production cost, long in service life and free of maintenance.
Description
Technical field
The present invention relates to unusual service condition detection technique field in electric energy metrical loop in electric system, be specially a kind of current transformer loop unusual service condition detection system.
Background technology
Along with the fast development of China's electric utility, power supply user constantly increases, stoichiometric point constantly increases thereupon, if measurement loop (as current transformer for metering loop, i.e. TA loop) breaks down, as short circuit of current loop, open circuit, shunting etc., then can cause improper metering, cause electric energy meter to count less, leak meter and even disregard, power supply enterprise then can cause the loss of electricity because of the fault in electric energy metrical loop, stealing etc., thus makes the benefit damage of country.
Summary of the invention
For the problems referred to above, the object of the present invention is to provide a kind of current transformer loop unusual service condition detection system, whether this detection system can the current return of three-phase electric energy meter in Real-Time Monitoring electric energy metrical loop normally be run.Technical scheme is as follows:
A kind of current transformer loop unusual service condition detection system, comprises AC constant-current source and impedance transformer, and the output terminal of described AC constant-current source connects the side of impedance transformer, and the opposite side of impedance transformer is for connecting TA loop; The output terminal of AC constant-current source is also connected to the input end of in-phase proportion amplifier, the input end of the output terminal connecting band bandpass filter of in-phase proportion amplifier, the input end of the output terminal connecting linear rectifier filer of bandpass filter.
Further, described AC constant-current source is made up of the bridge oscillators connected in turn, voltage follower and constant current resistance, and described bridge oscillators is the Wien-bridge oscillator connected and composed by 1,2,3 pins and the peripheral Resistor-Capacitor Unit of amplifier integrated circuit TL074; Described voltage follower comprises 5,6,7 pins of amplifier integrated circuit TL074, and the pin 6 that the pin 5 of described TL074 is connected to the pin 1, TL074 of TL074 connects the pin 7 of TL074; The pin 7 of TL074 is connected to the one end of the constant current resistance be made up of resistance R16 and R17 parallel connection, and the other end of constant current resistance forms the output terminal of described AC constant-current source.
Further, described in-phase proportion amplifier connects peripheral resistive element by 8,9,10 pins of amplifier integrated circuit TL074 and forms, and described peripheral resistive element comprises R10, R13 and R8; The pin 10 of TL074 forms the input end of described in-phase proportion amplifier; The pin 9 of TL074 by resistance R10 ground connection, and is connected by the pin 8 of resistance R13 and TL074; One end of the pin 8 contact resistance R8 of TL074, the other end of resistance R8 forms the output terminal of described in-phase proportion amplifier.
Further, described bandpass filter connects peripheral Resistor-Capacitor Unit by 12,13,14 pins of amplifier integrated circuit TL074 and forms, and described peripheral Resistor-Capacitor Unit comprises resistance R1, resistance R6, electric capacity C7 and electric capacity C11; One end of described electric capacity C7 forms the input end of described bandpass filter, and this end is also connected to the pin 12 of TL074 by electric capacity C11, and by resistance R6 ground connection; The pin 14 that the other end of electric capacity C7 is connected to the pin 14, TL074 of TL074 is also connected to pin 12 ground connection of the pin 13, TL074 of TL074 by resistance R1, the pin 14 of TL074 forms the output terminal of described bandpass filter.
Further, described line rectification wave filter is by double operational integrated circuit TL082 and peripheral Resistor-Capacitor Unit, and high-frequency rectification diode D1 and high-frequency rectification diode D2 is formed, described peripheral Resistor-Capacitor Unit comprises resistance R2, resistance R3, resistance R5 and electrochemical capacitor C12; The pin 2 of described TL082 is successively by D2, D1 and electrochemical capacitor C12 ground connection, and the positive pole of D1 connects the positive pole of the negative pole connection electrochemical capacitor C12 of the negative pole of D2 and the pin 1, D1 of TL082 simultaneously; One end of resistance R3 forms the input end of described line rectification wave filter, and the other end of resistance R3 is connected to the pin 2 of TL082 by resistance R5, and this end is also connected to the positive pole of electrochemical capacitor C12 by resistance R2; The pin 7 of TL082 is signal output part.
Further, also comprise voltage follower, the pin 5 that described voltage follower comprises the pin 5,6,7, described TL0825 of double operational integrated circuit TL082 is connected to the positive pole of described electrochemical capacitor C12, and the pin 6 of TL082 is connected to the pin 7 of TL082.
The invention has the beneficial effects as follows: the present invention can carry out Real-Time Monitoring to TA loop, can break down in TA loop occur improper metering time, timely faults result, so that management of power use unit fixes a breakdown in time, also can the generation of the effective improper electricity consumption situation such as electricity theft prevention, avoid the loss of national interests; And this test macro low production cost, long service life, non-maintaining.
Accompanying drawing explanation
Fig. 1 is current transformer loop unusual service condition detection system structured flowchart of the present invention.
Fig. 2 is current transformer loop unusual service condition detection system circuit theory diagrams of the present invention.
Embodiment
Below in conjunction with the drawings and specific embodiments, the present invention will be further described: as shown in Figure 1, a kind of current transformer loop unusual service condition detection system, comprise AC constant-current source and impedance transformer, the output terminal of described AC constant-current source connects the side of impedance transformer, and the opposite side of impedance transformer is for connecting TA loop; The output terminal of AC constant-current source is also connected to the input end of in-phase proportion amplifier, the input end of the output terminal connecting band bandpass filter of in-phase proportion amplifier, the input end of the output terminal connecting linear rectifier filer of bandpass filter.
According to the principles of electric and electronic engineering, the impedance in TA loop comprises resistance and reactance two parts, and reactance is divided into again capacitive reactance and induction reactance; At the same conditions, test with the interchange constant current signal of fixed frequency, its impedance is constant in the impedance in TA loop; When TA loop operating mode changes, as there is the situations such as short circuit, open circuit, shunting, under the test signal of identical frequency, will there is corresponding change in the impedance in TA loop, this impedance variation is converted to the change of level signal, just can reflect the actual condition in TA loop; According to the actual condition in TA loop, just can judge whether user is non-normal electricity consumption, if shunting, just can judge user's stealing.
The ultimate principle of impedance measurement is Method of constant flow source, and adopts AC constant-current source.Measure the voltage being connected on these constant-current source circuit middle impedance transducer two ends, thus draw the impedance in TA loop, namely indirectly measure the impedance in TA loop.Because A/B/C three-phase principle of work is identical, just for wherein A phase, circuit theory diagrams as shown in Figure 2.
AC constant-current source is made up of the bridge oscillators connected in turn, voltage follower and constant current resistance.Described bridge oscillators is the Wien-bridge oscillator connected and composed by 1,2,3 pins and the peripheral Resistor-Capacitor Unit of amplifier integrated circuit TL074.The pin 1 of TL074 is successively by resistance R4, electric capacity C8, and the electric capacity C13 of parallel connection and resistance R9 ground connection, and the pin 1 of TL074 also connects the pin 2 of TL074 by resistance R7; The pin 2 of TL074 is by resistance R11, resistance R1 parallel with one another, potentiometer R14 and potentiometer R15 ground connection; The pin 3 of TL074 is connected between electric capacity C8 and electric capacity C13.Oscillation frequency is determined by external resistor-capacitor element, and theoretical calculation formula is: f=1/2 π RC; Through actual measurement, selected frequency 80KHz(calculated value is 85.8KHz), survey its frequency and change with supply voltage, under the condition of the present embodiment circuit, if supply voltage is ± 5v, then f=0.932/2 π RC, so R4 selects 3.9K, C8 to select 220pF; R7, R11, R12 are Gain tuning and fixed ampllitude element.Export amplitude by element in figure and be about 7Vp-p, amount to sinusoidal wave effective value and be about 2.48V, waveform all slightly slicing up and down, but last test result is not affected.Test be the resulting impedance in TA loop, resulting impedance comprises direct current resistance, the induction reactance in TA loop and the capacitive reactance etc. that distributes, for reducing direct current resistance with distribution capacitive reactance to the impact of this test loop impedance, choosing frequency test signal after actual measurement is 80KHz, then all can reach desirable test effect to the TA loop that the TA of all size of each producer is formed.
The AC signal that oscillator exports exports through voltage follower, and after constant current resistance, constant current output.Voltage follower can isolate oscillator and tested loop, can improve again the carrying load ability of test high-frequency signal.Voltage follower comprises 5,6,7 pins of amplifier integrated circuit TL074, and the pin 6 that the pin 5 of described TL074 is connected to the pin 1, TL074 of TL074 connects the pin 7 of TL074; The pin 7 of TL074 is connected to the one end of the constant current resistance be made up of resistance R16 and R17 parallel connection, and the other end of constant current resistance forms the output terminal of described AC constant-current source.
Constant current AC signal, through impedance transformer T1, is coupled to TA loop, and TA loop is serially connected on 3,4 pin of impedance transformer T1, as shown in Figure 2.Constant current AC test signals input in-phase proportion amplifier, enlargement factor is 10 times.In-phase proportion amplifier connects peripheral resistive element by 8,9,10 pins of amplifier integrated circuit TL074 and forms, and described peripheral resistive element comprises R10, R13 and R8; The pin 10 of TL074 forms the input end of described in-phase proportion amplifier; The pin 9 of TL074 by resistance R10 ground connection, and is connected by the pin 8 of resistance R13 and TL074; One end of the pin 8 contact resistance R8 of TL074, the other end of resistance R8 forms the output terminal of described in-phase proportion amplifier.
Test signal is after amplifying, and input tape bandpass filter, the various interference of filtering and spurious oscillation, export ideal sine wave, for follow-up linear rectification circuit.Bandpass filter connects peripheral Resistor-Capacitor Unit by 12,13,14 pins of amplifier integrated circuit TL074 and forms, and described peripheral Resistor-Capacitor Unit comprises resistance R1, resistance R6, electric capacity C7 and electric capacity C11; One end of described electric capacity C7 forms the input end of described bandpass filter, and this end is also connected to the pin 12 of TL074 by electric capacity C11, and by resistance R6 ground connection; The pin 14 that the other end of electric capacity C7 is connected to the pin 14, TL074 of TL074 is also connected to pin 12 ground connection of the pin 13, TL074 of TL074 by resistance R1, the pin 14 of TL074 forms the output terminal of described bandpass filter.
Bandpass filter is exported high_frequency sine wave and is transformed into direct current by line rectification wave filter, is exported by low 7 pin of double operational integrated circuit TL082.Line rectification wave filter is by TL082 and peripheral Resistor-Capacitor Unit, and high-frequency rectification diode D1 and high-frequency rectification diode D2 is formed, and described peripheral Resistor-Capacitor Unit comprises resistance R2, resistance R3, resistance R5 and electrochemical capacitor C12; The pin 2 of described TL082 is successively by D2, D1 and electrochemical capacitor C12 ground connection, and the positive pole of D1 connects the positive pole of the negative pole connection electrochemical capacitor C12 of the negative pole of D2 and the pin 1, D1 of TL082 simultaneously; One end of resistance R3 forms the input end of described line rectification wave filter, and the other end of resistance R3 is connected to the pin 2 of TL082 by resistance R5, and this end is also connected to the positive pole of electrochemical capacitor C12 by resistance R2; The pin 7 of TL082 is signal output part.Wherein, D1 and D2 model is 1N5819.Voltage follower plays isolation and amplifier and improves the effect of load capacity.The pin 5 that described voltage follower comprises the pin 5,6,7, TL0825 of double operational integrated circuit TL082 is connected to the positive pole of described electrochemical capacitor C12, and the pin 6 of TL082 is connected to the pin 7 of TL082.
Select all integrated transporting dischargings in negative pressure integrated circuit (IC) L7660 supply circuit to use, it generates a negative voltage, and amplifier is always worked in a normal range of the present embodiment requirement.
Claims (6)
1. a current transformer loop unusual service condition detection system, is characterized in that, comprises AC constant-current source and impedance transformer, and the output terminal of described AC constant-current source connects the side of impedance transformer, and the opposite side of impedance transformer is for connecting TA loop; The output terminal of AC constant-current source is also connected to the input end of in-phase proportion amplifier, the input end of the output terminal connecting band bandpass filter of in-phase proportion amplifier, the input end of the output terminal connecting linear rectifier filer of bandpass filter.
2. current transformer loop unusual service condition detection system according to claim 1, it is characterized in that, described AC constant-current source is made up of the bridge oscillators connected in turn, voltage follower and constant current resistance, and described bridge oscillators is the Wien-bridge oscillator connected and composed by 1,2,3 pins and the peripheral Resistor-Capacitor Unit of amplifier integrated circuit TL074; Described voltage follower comprises 5,6,7 pins of amplifier integrated circuit TL074, and the pin 6 that the pin 5 of described TL074 is connected to the pin 1, TL074 of TL074 connects the pin 7 of TL074; The pin 7 of TL074 is connected to the one end of the constant current resistance be made up of resistance R16 and R17 parallel connection, and the other end of constant current resistance forms the output terminal of described AC constant-current source.
3. current transformer loop unusual service condition detection system according to claim 1, it is characterized in that, described in-phase proportion amplifier connects peripheral resistive element by 8,9,10 pins of amplifier integrated circuit TL074 and forms, and described peripheral resistive element comprises R10, R13 and R8; The pin 10 of TL074 forms the input end of described in-phase proportion amplifier; The pin 9 of TL074 by resistance R10 ground connection, and is connected by the pin 8 of resistance R13 and TL074; One end of the pin 8 contact resistance R8 of TL074, the other end of resistance R8 forms the output terminal of described in-phase proportion amplifier.
4. current transformer loop unusual service condition detection system according to claim 1, it is characterized in that, described bandpass filter connects peripheral Resistor-Capacitor Unit by 12,13,14 pins of amplifier integrated circuit TL074 and forms, and described peripheral Resistor-Capacitor Unit comprises resistance R1, resistance R6, electric capacity C7 and electric capacity C11; One end of described electric capacity C7 forms the input end of described bandpass filter, and this end is also connected to the pin 12 of TL074 by electric capacity C11, and by resistance R6 ground connection; The pin 14 that the other end of electric capacity C7 is connected to the pin 14, TL074 of TL074 is also connected to pin 12 ground connection of the pin 13, TL074 of TL074 by resistance R1, the pin 14 of TL074 forms the output terminal of described bandpass filter.
5. the current transformer loop unusual service condition detection system according to any one of claim 1-4, it is characterized in that, described line rectification wave filter is by double operational integrated circuit TL082 and peripheral Resistor-Capacitor Unit, and high-frequency rectification diode D1 and high-frequency rectification diode D2 is formed, described peripheral Resistor-Capacitor Unit comprises resistance R2, resistance R3, resistance R5 and electrochemical capacitor C12; The pin 2 of described TL082 is successively by D2, D1 and electrochemical capacitor C12 ground connection, and the positive pole of D1 connects the positive pole of the negative pole connection electrochemical capacitor C12 of the negative pole of D2 and the pin 1, D1 of TL082 simultaneously; One end of resistance R3 forms the input end of described line rectification wave filter, and the other end of resistance R3 is connected to the pin 2 of TL082 by resistance R5, and this end is also connected to the positive pole of electrochemical capacitor C12 by resistance R2; The pin 7 of TL082 is signal output part.
6. current transformer loop unusual service condition detection system according to claim 5, it is characterized in that, also comprise voltage follower, described voltage follower comprises the pin 5,6,7 of double operational integrated circuit TL082, the pin 5 of described TL0825 is connected to the positive pole of described electrochemical capacitor C12, and the pin 6 of TL082 is connected to the pin 7 of TL082.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201510360024.2A CN104950280B (en) | 2015-06-26 | 2015-06-26 | A kind of current transformer loop unusual service condition detecting system |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201510360024.2A CN104950280B (en) | 2015-06-26 | 2015-06-26 | A kind of current transformer loop unusual service condition detecting system |
Publications (2)
Publication Number | Publication Date |
---|---|
CN104950280A true CN104950280A (en) | 2015-09-30 |
CN104950280B CN104950280B (en) | 2018-02-09 |
Family
ID=54165078
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201510360024.2A Active CN104950280B (en) | 2015-06-26 | 2015-06-26 | A kind of current transformer loop unusual service condition detecting system |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN104950280B (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN106226638A (en) * | 2016-08-26 | 2016-12-14 | 四川和中电力科技有限公司 | A kind of low voltage mutual inductor measurement loop state on_line monitoring system |
CN110132118A (en) * | 2019-06-13 | 2019-08-16 | 重庆红江机械有限责任公司 | A kind of displacement detection system based on LVDT sensor |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
PL160127B1 (en) * | 1989-10-18 | 1993-02-26 | Politechnika Wroclawska | Circuit for checking an alternating current transformer |
CN1787714A (en) * | 2005-10-15 | 2006-06-14 | 阮树成 | Ballast of random noise and sawtooth wave composite frequency modulation for gold halogen lamp |
CN201251596Y (en) * | 2008-06-25 | 2009-06-03 | 三门利达电器有限公司 | Anti-theft electric pulse type precise current transformer combination |
CN204028268U (en) * | 2014-06-26 | 2014-12-17 | 镇江瑞清电子科技有限公司 | A kind of secondary loop of mutual inductor failure detector and signal conversion circuit thereof |
CN204758817U (en) * | 2015-06-26 | 2015-11-11 | 国家电网公司 | Current transformer return circuit unusual service condition detecting system |
-
2015
- 2015-06-26 CN CN201510360024.2A patent/CN104950280B/en active Active
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
PL160127B1 (en) * | 1989-10-18 | 1993-02-26 | Politechnika Wroclawska | Circuit for checking an alternating current transformer |
CN1787714A (en) * | 2005-10-15 | 2006-06-14 | 阮树成 | Ballast of random noise and sawtooth wave composite frequency modulation for gold halogen lamp |
CN201251596Y (en) * | 2008-06-25 | 2009-06-03 | 三门利达电器有限公司 | Anti-theft electric pulse type precise current transformer combination |
CN204028268U (en) * | 2014-06-26 | 2014-12-17 | 镇江瑞清电子科技有限公司 | A kind of secondary loop of mutual inductor failure detector and signal conversion circuit thereof |
CN204758817U (en) * | 2015-06-26 | 2015-11-11 | 国家电网公司 | Current transformer return circuit unusual service condition detecting system |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN106226638A (en) * | 2016-08-26 | 2016-12-14 | 四川和中电力科技有限公司 | A kind of low voltage mutual inductor measurement loop state on_line monitoring system |
CN110132118A (en) * | 2019-06-13 | 2019-08-16 | 重庆红江机械有限责任公司 | A kind of displacement detection system based on LVDT sensor |
Also Published As
Publication number | Publication date |
---|---|
CN104950280B (en) | 2018-02-09 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN103454517B (en) | Capacitance type potential transformer on-line monitoring method | |
CN104849649A (en) | System and method for detecting state of secondary circuit of current transformer for metering | |
CN204613359U (en) | A kind of detection system of current transformer for metering secondary circuit state | |
CN104569902A (en) | Digital type electric energy meter power consumption measuring device and method | |
CN204758817U (en) | Current transformer return circuit unusual service condition detecting system | |
CN116449164B (en) | Insulation detection method, system and storage medium for industrial and commercial energy storage alternating current-direct current system | |
CN204694824U (en) | Variable-frequency motor intelligent test device | |
CN104950280A (en) | System for detecting abnormal working conditions of current transformer loop | |
CN204374272U (en) | A kind of mutual inductor mode transformer grounding leakage current wireless monitoring device | |
CN204241574U (en) | A kind of power capacitor on-line measurement device | |
CN203414136U (en) | Liquid-level sensor circuit | |
CN101938147B (en) | Uninterruptable power supply aging self-feedback control method and system | |
CN105093161A (en) | Gateway electric energy meter online replacing mode electric quantity loss compensation metering system | |
CN102291018A (en) | Single-phase rectifier with APFC (active power factor correction) circuit and alternating-current input voltage amplitude detection method thereof | |
CN102255317B (en) | Earthquake alarm household electronic power saver | |
CN201515355U (en) | Automatic frequency-selection narrowband bandpass filter | |
CN208721743U (en) | A kind of Assembled high-voltage shunted capacitor set detecting device | |
CN204925279U (en) | Steal electric detection means | |
CN204044261U (en) | A kind of electrical network resistance characteristic test device frequently | |
CN103424643A (en) | Ground fault detecting device | |
CN205679593U (en) | A kind of imflammable gas detector based on bluetooth | |
CN202502131U (en) | Voltage/current detecting circuit | |
CN201876495U (en) | Power harmonic intelligent detecting device | |
CN105675996B (en) | A kind of power battery internal resistance on-line monitoring system and method | |
CN204945239U (en) | Electric quantity loss compensate for malfunctions device under the online substitute mode of a kind of gate energy meter |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
C06 | Publication | ||
PB01 | Publication | ||
C10 | Entry into substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |