CN2264916Y - Sensor of intelligent watt-hour meter - Google Patents
Sensor of intelligent watt-hour meter Download PDFInfo
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- CN2264916Y CN2264916Y CN 96235689 CN96235689U CN2264916Y CN 2264916 Y CN2264916 Y CN 2264916Y CN 96235689 CN96235689 CN 96235689 CN 96235689 U CN96235689 U CN 96235689U CN 2264916 Y CN2264916 Y CN 2264916Y
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Abstract
The utility model belongs to a fitting for electrical degree and electric power measuring meters, particularly a sensor for intelligent watt-hour meters, utilizing the hall effect. The sensor for intelligent watt-hour meters is composed of a sensing head, a power and frequency converter and a isolating follower, wherein, the isolating follower after improved can display average power; the sensing head after changed differently can provide precise intelligent watt-hour meters and three-phase Intelligent watt-hour meters. Compared with the existing intelligent watt-hour meter, a multiplier, an A/D converting circuit, etc. are omitted. Therefore, the utility model has the advantages of small volume, convenient operation and low cost and is favorable to the popularization of the intelligent watt-hour meters.
Description
The utility model belongs to the accessory of a kind of electric degree, electric power measurement instrument, refers in particular to the sensor that utilizes Hall effect.
In the prior art, the multifunctional intelligent kilowatt-hour meter that RECENT DEVELOPMENTS is got up is the technology of a new development, it adopts two kinds of impression methods usually to the impression of power, a kind of is to gather magnitude of voltage and current value respectively with voltage sensor and current sensor, multiply each other by multiplier then, be converted to digital quantity by A/D converter again; Another kind is to adopt old-fashioned watt-hour meter as sensor, surveys its rotating speed and obtains the electric degree value.There is complex circuit in first method, and there are the problem of sensor heaviness, low precision again in the problem that cost is high, second method.
The purpose of this utility model is the shortcoming that overcomes existing intelligent kilowatt-hour meter, the sensor that provides the intelligent kilowatt-hour meter of the simulation blocking that a kind of cost is low, volume is small and exquisite to use.
The know-why of the utility model embodiment is: utilize Hall four end member spares to the multiplication characteristic that input current and magnetic field of living in have, omitted many expensive complicated links such as multiplier and analog-converted, obtain direct active electrical degree output.Line voltage dividing potential drop sampling after the voltage follower that an operational amplifier is formed as the input of Hall element, then the input current Ic=K of Hall element
1Vs, K
1Be constant, Vs is the instantaneous value of line voltage; Mains current adds to Hall element by a magnet ring around lead with the magnetic field that electric current produces, then magnetic field intensity B=K
2Is, K
2Be constant, Is is the mains current instantaneous value.Because the multiplication characteristic of Hall element, then its output V
H=K
3IcB=KIsVs=KPs, wherein K
3, K is constant, Ps is the power instantaneous value, because of civil power for exchanging, so the Ps value has Alternating Component and direct current composition, wherein the direct current composition is an active power.To Ps amplify, integration, and integrated value is converted into pulse, then umber of pulse N just is proportional between active power takes the opportunity, it is active electrical degree, simultaneously because of civil power for exchanging, Hall element itself the error that produces of intrinsic offset resistance Rp can be eliminated, the error size that Rp produces when the positive and negative alternation of Vs is equal, opposite in sign is zero behind integration.Be that the electric degree sensor that the center is formed can guarantee basic accuracy with Hall element and operational amplifier like this.
Concrete technology implementation scheme of the present utility model is: the sensor of intelligent kilowatt-hour meter adopts sensing head, power-frequency converter and isolation follower three parts are formed, sensing head is that R1 and P1 are connected in series between live wire and the zero line, zero line is made simulation ground, its intermediate contact inserts the in-phase end of operational amplifier L1:A, the end of oppisite phase of L1:A and output terminal short circuit, constitute voltage follower, the output of L1:A is connected to an input pin of four end Hall elements, another input pin of Hall element H1 connects simulation ground, two output pins are connected to in-phase end and the end of oppisite phase of operational amplifier L1:B respectively, Hall unit H1 is installed in the crack of a magnetic guiding loop, live wire passes from magnetic guiding loop, resistance R 3 is connected between the in-phase end and simulation ground wire of L1:B, resistance R 2 is connected between the end of oppisite phase and output terminal of L1:B, the output terminal of L1:B is connected to the output of sensing head by R4, the input of power-frequency converter connects the end of oppisite phase of operational amplifier L1:C, be connected to a capacitor C 1 between the end of oppisite phase of L1:C and the output terminal, the in-phase end of L1:C is connected to simulation ground by R5, the output terminal of L1:C is connected to the inverting input of L1:D again, two of the in-phase end of L1:D series connection are Zener diode Z1 back-to-back, be connected to simulation ground behind the Z2, also be connected to resistance R 6 between L1:D in-phase end and the output terminal.The output terminal of L1:D links to each other with the base stage of triode N1 by resistance R 7 again, the emitter of N1 is connected to-the 10V power supply by stabilivolt Z3, the collector of N1 is connected to the end of oppisite phase of L1:C, the output terminal of power-frequency converter picks out from the output terminal of L1:D, the input signal of isolating follower, be connected to the positive input pin of photoelectrical coupler L2 by resistance R 8, the negative input pin of L2 is connected to simulation ground, and the collector output pin of L2 is connected to output terminal 2 pin of isolating follower; Its emitter output pin is connected to output terminal 3 pin of isolating follower, and whole sensor is by isolating 2, the 3 pin output of follower.
The utility model has the advantages that: make intelligent kilowatt-hour meter can save multiplier and A/D change-over circuit etc. and directly show the electric degree number, make whole intelligent kilowatt-hour meter volume small and exquisite, easy to use, cost is low, helps popularizing of intelligent kilowatt-hour meter greatly.
Accompanying drawing 1 is the theory diagram of the utility model technical application scheme.
Accompanying drawing 2 is the sensing head wiring diagram of embodiment 1.
Accompanying drawing 3 is the Hall element scheme of installation of embodiment 1.
Accompanying drawing 4 is the wiring diagram of the power-frequency converter of embodiment 1.
Accompanying drawing 5 is the isolation follower wiring diagram of embodiment 1.
Accompanying drawing 6 is the isolation follower wiring diagram of embodiment 2.
Accompanying drawing 7 is the sensing head wiring diagram of embodiment 3.
Accompanying drawing 8 is the sensing head wiring diagram of embodiment 4.
Accompanying drawing 9 is the sensing head wiring diagram of embodiment 5.
Embodiment 1:
The sensor of this intelligent kilowatt-hour meter is made up of sensing head, power-frequency converter and isolation follower three parts as shown in Figure 1, and line of electric force inserts sensing head, and the output of sensing head is connected to the input of power-frequency converter; The output of power-frequency converter is connected to the input of isolating follower.Whole sensor is by isolating the 2nd, the 3 pin output of follower.The line construction of sensing head as shown in Figure 2, it is that R1 and P1 are connected in series between live wire and the zero line, zero line is made simulation ground, its intermediate contact inserts the in-phase end of operational amplifier L1:A, the end of oppisite phase of L1:A and output terminal short circuit, constitute voltage follower, the output of L1:A is connected to an input pin of four end Hall elements, another input pin of Hall element H1 connects simulation ground, two output pins are connected to in-phase end and the end of oppisite phase of operational amplifier L1:B respectively, Hall unit H1 as shown in Figure 3, be installed in the crack of a magnetic guiding loop, live wire passes from magnetic guiding loop, and resistance R 3 is connected between the in-phase end and simulation ground wire of L1:B, resistance R 2 is connected between the end of oppisite phase and output terminal of L1:B, and the output terminal of L1:B is connected to the output of sensing head by R4.The line construction of power-frequency converter as shown in Figure 4, the input of power-frequency converter connects the end of oppisite phase of operational amplifier L1:C, be connected to an electrical equipment C1 between the end of oppisite phase of L1:C and the output terminal, the in-phase end of L1:C is connected to simulation ground by R5, the output terminal of L1:C is connected to the inverting input of L1:D again, two of the in-phase end series connection of L1:D are connected to simulation ground behind Zener diode Z1, the Z2 back-to-back, also are connected to resistance R 6 between L1:D in-phase end and the output terminal.The output terminal of L1:D links to each other with the base stage of triode N1 by resistance R 7 again, and the emitter of N1 is connected to-the 10V power supply by stabilivolt Z3, and the collector of N1 is connected to the end of oppisite phase of L1:C, and the output terminal of power-frequency converter picks out from the output terminal of L1:D.The line construction of isolating follower is isolated the input signal of follower as shown in Figure 5, is connected to the positive input pin of photoelectrical coupler L2 by resistance R 8, and the negative input pin of L2 is connected to simulation ground, and the collector output pin of L2 is connected to output terminal 2 pin of isolating follower; Its emitter output pin is connected to output terminal 3 pin of isolating follower, and whole sensor is by isolating 2, the 3 pin output of follower.
Embodiment 2:
In order to make intelligent kilowatt-hour meter demonstrate average power, on the basis of embodiment 1, the line construction of isolating follower is carried out as shown in Figure 6 improvement, the input signal of isolating follower is connected to the positive input pin of photoelectrical coupler L2 by R8, the negative input pin of L2 is connected to simulation ground, the emitter output ground connection of L2, the collector output of L2 is connected to the Cp end of technology device L5, the Cp end of L5 is connected to+5V by a pull-up resistor R19, L5 is a tetrad counter, its A, B, C, four output terminals of D are connected to preceding four input ends of eight D-latch L7, wherein the D output terminal also connects the Cp end of another counter L6, the A of L6, B, C, D four output terminals are connected to back four input ends of L7, eight output terminals of L7 are as the output of the eight-digit binary number of converter, counter L5, the removing end Cr of L6 and the clock end Cp of latch L7 are connected together, draw from output terminal 3 pin of oscillator L4,1 pin of oscillator L4 connects digitally, 4,8 pin meet power supply+5V, 5 pin connect digitally by capacitor C 3,2 pin, connect digitally by capacitor C 2 behind the 6 pin short circuits, connect a resistance R 17 between power supply+5V and 7 pin, connect a resistance R 18 between 7 pin and 2 pin, form oscillator with this.
Embodiment 3:
For more accurate intelligent kilowatt-hour meter can be provided, line construction to sensing head on the basis of embodiment 1 is pressed improvement shown in Figure 7, the resistance R 1 of sensing head and potentiometer P1 are connected in series between live wire and the zero line, zero line is as sensing head simulation ground, the contact of R1 and P1 is connected to the in-phase end of L3:A again, the end of oppisite phase of L3:A and output terminal are connected to two input pins of Hall element H1 respectively, resistance R 9 is connected between the end of oppisite phase of simulation ground and L3:A, Hall element H1 is arranged in the crack of a magnetic guiding loop, live wire passes from magnetic guiding loop, the output of H1 is connected to two operational amplifier L3:B respectively, the in-phase end of L3:C, the end of oppisite phase of L3:B and L3:C links to each other by a resistance R 12, respectively be connected to a resistance R 10 and a R11 between the end of oppisite phase of these two operational amplifiers and the output terminal simultaneously, the output terminal of L3:B and L3:C is connected to in-phase end and the end of oppisite phase of operational amplifier L3:D respectively by resistance R 13 and R14, be connected to resistance R 16 between the end of oppisite phase of L3:D and the output terminal, the in-phase end of L3:D is connected to simulation ground by R15, and the output of L3:D is connected to the output of sensing head by R4.
Embodiment 4:
In order to make intelligent kilowatt-hour meter can be used to show the power of three-phase electricity consumption, line construction to sensing head on the basis of embodiment 1 improves by shown in Figure 8, the input power line of sensing head is A, B, the C three-phase, with B as simulation ground, between A and simulation ground and C and simulation ground, insert connecting of a pair of R1 and P1 respectively, two intermediate contacts respectively insert the in-phase end of two L1:A, the end of oppisite phase of two L1:A is connected to the input pin of two H1 respectively, another input pin of two H1 all connects simulation ground, two H1 are installed in respectively in the magnetic gap of two magnet rings, line of electric force A passes from a magnet ring, C passes from another magnet ring, the in-phase end of two L1:B all connects simulation ground by R3, and end of oppisite phase all connects separately output terminal by R2, and output terminal separately all is connected to the output of sensing head again by R4.
Embodiment 5:
In order to make intelligent kilowatt-hour meter can critically show the power of three-phase electricity consumption, line construction to sensing head on the basis of embodiment 1 improves by shown in Figure 9, the input power line of sensing head is A, B, the C three-phase, with B as simulation ground, between A and simulation ground and C and simulation ground, insert connecting of a pair of R1 and P1 respectively, two intermediate contacts are connected to the in-phase end of two L3:A respectively, the end of oppisite phase of two L3:A and output terminal are connected to the input pin of two H1 respectively, the in-phase end of two L3:A all passes through R9 ground connection, two H1 lay respectively in the magnetic gap of two magnetic guiding loops, A phase line and C phase line are respectively passed a magnetic guiding loop, two outputs of a H1 respectively connect the in-phase end of L3:B and L3:C, the end of oppisite phase of L3:B and L3:C joins by R12, the two-way output of another H1 respectively connects another in-phase end to operational amplifier L3:B and L3:C, the end of oppisite phase of L3:C and L3:B joins by R12, the end of oppisite phase of two L3:B respectively is connected to output terminal separately by R10 simultaneously, the end of oppisite phase of two L3:C respectively is connected to output terminal separately by R11, two L3:B output terminals respectively connect two L3:D in-phase ends by R13, two L3:C output terminals respectively connect the end of oppisite phase of two L3:D by R14, the end of oppisite phase of two L3:D respectively connects its output terminal by R16, two L3:D in-phase ends respectively connect simulation ground by R15, and two L3:D output terminals respectively are connected to sensing head output by R4.
The used element selected parameter of each embodiment of the utility model is as follows:
Resistance:
R1： 1MΩ～10MΩ， R2：10KΩ～100KΩ，
R3： 10KΩ～100KΩ， R4：100KΩ～1MΩ，
R5： 100KΩ～1MΩ， R6：1KΩ～50KΩ，
R7： 100Ω～10KΩ， R8： 100Ω～2KΩ，
R9： 100Ω～1KΩ， R10： 1KΩ～100KΩ，
R11： 1KΩ～100KΩ， R12： 100Ω～7KΩ，
R13： 1KΩ～10KΩ， R14： 1KΩ～10KΩ，
R15： 10KΩ～100KΩ， R16： 10KΩ～100KΩ，
R17： 5KΩ～50KΩ， R18： 1KΩ～10KΩ，
R19： 10KΩ～200KΩ。Electric capacity:
C1：0.2～1μf，C2：0.1μf～0.5μf，C3：0.01μf。Potentiometer: P1:100K Ω-400 Ω K.Stabilivolt: Z1:3V～6V, Z2:3V～6V, Z3:3V～6V.Triode: N1: miniwatt NPN pipe, as 3DG6,9013 etc.Integrated circuit: L1: four-operational amplifier, as LM324 etc.,
L2: photoelectrical coupler, as 4N29,4N26 etc.,
L3: accurate four-operational amplifier, as OP11 etc.,
The L4:555 oscillator,
L5: counter, as 74163,74LS163 etc.,
L6: counter, as 74163,74LS163 etc.,
L7: eight D-latchs, as 74377,74LS377 etc., Hall element: H1: four end Hall elements, as THS103A, OH001 etc.
Claims (5)
1, a kind of sensor of intelligent kilowatt-hour meter, it is characterized in that: it is by sensing head, power-frequency converter and isolation follower three parts are formed, sensing head is that R1 and P1 are connected in series between live wire and the zero line, zero line is made simulation ground, its intermediate contact inserts the in-phase end of operational amplifier L1:A, the end of oppisite phase of L1:A and output terminal short circuit, constitute voltage follower, the output of L1:A is connected to an input pin of four end Hall elements, another input pin of Hall element H1 connects simulation ground, two output pins are connected to in-phase end and the end of oppisite phase of operational amplifier L1:B respectively, Hall unit H1 is installed in the crack of a magnetic guiding loop, live wire passes from magnetic guiding loop, resistance R 3 is connected between the in-phase end and simulation ground wire of L1:B, resistance R 2 is connected between the end of oppisite phase and output terminal of L1:B, the output terminal of L1:B is connected to the output of sensing head by R4, the input of power-frequency converter connects the end of oppisite phase of operational amplifier L1:C, be connected to an electrical equipment C1 between the end of oppisite phase of L1:C and the output terminal, the in-phase end of L1:C is connected to simulation ground by R5, the output terminal of L1:C is connected to the inverting input of L1:D again, two of the in-phase end of L1:D series connection are Zener diode Z1 back-to-back, be connected to simulation ground behind the Z2, also be connected to resistance R 6 between L1:D in-phase end and the output terminal.The output terminal of L1:D links to each other with the base stage of triode N1 by resistance R 7 again, the emitter of N1 is connected to-the 10V power supply by stabilivolt Z3, the collector of N1 is connected to the end of oppisite phase of L1:C, the output terminal of power-frequency converter picks out from the output terminal of L1:D, the input signal of isolating follower, be connected to the positive input pin of photoelectrical coupler L2 by resistance R 8, the negative input pin of L2 is connected to simulation ground, and the collector output pin of L2 is connected to output terminal 2 pin of isolating follower; Its emitter output pin is connected to output terminal 3 pin of isolating follower, and whole sensor is by isolating 2, the 3 pin output of follower.
2, the sensor of intelligent kilowatt-hour meter as claimed in claim 1, it is characterized in that: the input signal of described isolation follower is connected to the positive input pin of photoelectrical coupler L2 by R8, the negative input pin of L2 is connected to simulation ground, the emitter output ground connection of L2, the collector output of L2 is connected to the Cp end of counter L5, the Cp end of L5 is connected to+5V by a pull-up resistor R19, L5 is a tetrad counter, its A, B, C, four output terminals of D are connected to preceding four input ends of eight D-latch L7, wherein the D output terminal also connects the Cp end of another counter L6, the A of L6, B, C, D four output terminals are connected to back four input ends of L7, eight output terminals of L7 are as the output of the eight-digit binary number of converter, counter L5, the removing end Cr of L6 and the clock end Cp of latch L7 are connected together, draw from output terminal 3 pin of oscillator L4,1 pin of oscillator L4 connects digitally, 4,8 pin meet power supply+5V, 5 pin connect digitally by capacitor C 3,2 pin, connect digitally by capacitor C 2 behind the 6 pin short circuits, connect a resistance R 17 between power supply+5V and 7 pin, connect a resistance R 18 between 7 pin and 2 pin, form oscillator with this.
3, the sensor of intelligent kilowatt-hour meter as claimed in claim 1 or 2, it is characterized in that: the resistance R 1 of described sensing head and potentiometer P1 are connected in series between live wire and the zero line, zero line is as sensing head simulation ground, the contact of R1 and P1 is connected to the in-phase end of L3:A again, the end of oppisite phase of L3:A and output terminal are connected to two input pins of Hall element H1 respectively, resistance R 9 is connected between the end of oppisite phase of simulation ground and L3:A, Hall element H1 is arranged in the crack of a magnetic guiding loop, live wire passes from magnetic guiding loop, the output of H1 is connected to two operational amplifier L3:B respectively, the in-phase end of L3:C, the end of oppisite phase of L3:B and L3:C links to each other by a resistance R 12, respectively be connected to a resistance R 10 and a R11 between the end of oppisite phase of these two operational amplifiers and the output terminal simultaneously, the output terminal of L3:B and L3:C is connected to in-phase end and the end of oppisite phase of operational amplifier L3:D respectively by resistance R 13 and R14, be connected to resistance R 16 between the end of oppisite phase of L3:D and the output terminal, the in-phase end of L3:D is connected to simulation ground by R15, and the output of L3:D is connected to the output of sensing head by R4.
4, the sensor of intelligent kilowatt-hour meter as claimed in claim 1 or 2, it is characterized in that: the input power line of described sensing head is A, B, the C three-phase, with B as simulation ground, between A and simulation ground and C and simulation ground, insert connecting of a pair of R1 and P1 respectively, two intermediate contacts respectively insert the in-phase end of two L1:A, the end of oppisite phase of two L1:A is connected to the input pin of two H1 respectively, another input pin of two H1 all connects simulation ground, two H1 are installed in respectively in the magnetic gap of two magnet rings, line of electric force A passes from a magnet ring, C passes from another magnet ring, the in-phase end of two L1:B all connects simulation ground by R3, end of oppisite phase all connects separately output terminal by R2, and output terminal separately all is connected to the output of sensing head again by R4.
5, the sensor of intelligent kilowatt-hour meter as claimed in claim 1 or 2, it is characterized in that: the input power line of described sensing head is A, B, the C three-phase, with B as simulation ground, between A and simulation ground and C and simulation ground, insert connecting of a pair of R1 and P1 respectively, two intermediate contacts are connected to the in-phase end of two L3:A respectively, the end of oppisite phase of two L3:A and output terminal are connected to the input pin of two H1 respectively, the in-phase end of two L3:A all passes through R9 ground connection, two H1 lay respectively in the magnetic gap of two magnetic guiding loops, A phase line and C phase line are respectively passed a magnetic guiding loop, two outputs of a H1 respectively connect the in-phase end of L3:B and L3:C, the end of oppisite phase of L3:B and L3:C joins by R12, the two-way output of another H1 respectively connects another in-phase end to operational amplifier L3:B and L3:C, the end of oppisite phase of L3:C and L3:B joins by R12, the end of oppisite phase of two L3:B respectively is connected to output terminal separately by R10 simultaneously, the end of oppisite phase of two L3:C respectively is connected to output terminal separately by R11, two L3:B output terminals respectively connect two L3:D in-phase ends by R13, two L3:C output terminals respectively connect the end of oppisite phase of two L3:D by R14, the end of oppisite phase of two L3:D respectively connects its output terminal by R16, two L3:D in-phase ends respectively connect simulation ground by R15, and two L3:D output terminals respectively are connected to sensing head output by R4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 96235689 CN2264916Y (en) | 1996-05-30 | 1996-05-30 | Sensor of intelligent watt-hour meter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 96235689 CN2264916Y (en) | 1996-05-30 | 1996-05-30 | Sensor of intelligent watt-hour meter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2264916Y true CN2264916Y (en) | 1997-10-15 |
Family
ID=33911676
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 96235689 Expired - Fee Related CN2264916Y (en) | 1996-05-30 | 1996-05-30 | Sensor of intelligent watt-hour meter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2264916Y (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101464479B (en) * | 2007-12-20 | 2012-09-26 | 东光东芝测量仪器株式会社 | Electric energy meter |
| CN103529287A (en) * | 2013-10-14 | 2014-01-22 | 国家电网公司 | Electric consumption information collecting system based on Hall sensor |
-
1996
- 1996-05-30 CN CN 96235689 patent/CN2264916Y/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101464479B (en) * | 2007-12-20 | 2012-09-26 | 东光东芝测量仪器株式会社 | Electric energy meter |
| CN103529287A (en) * | 2013-10-14 | 2014-01-22 | 国家电网公司 | Electric consumption information collecting system based on Hall sensor |
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| CF01 | Termination of patent right due to non-payment of annual fee |