CN108152635A - A kind of three-phase ac signal vasculum - Google Patents
A kind of three-phase ac signal vasculum Download PDFInfo
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- CN108152635A CN108152635A CN201810013678.1A CN201810013678A CN108152635A CN 108152635 A CN108152635 A CN 108152635A CN 201810013678 A CN201810013678 A CN 201810013678A CN 108152635 A CN108152635 A CN 108152635A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
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Abstract
The invention discloses three-phase ac signal vasculums; it is related to signal processing technology field; with TMS320F28335 devices in order to control; it is realized using three-phase AC sampling method and power network signal is acquired in real time; voltage effective value is shown, and pass through the relay protection function that failure is set to realize electric system by liquid crystal display LCD12864.It is simple in structure by testing the vasculum of the present invention using the voltage-controlled low-pass filter circuit of second order is with good stability and precision, at low cost, the advantages that stability is good.Synchronous generator exciting regulating system, measuring instrument instrument, relay protection system etc. can be used in, there is good use value.
Description
Technical field
The present invention relates to signal processing technology field, more particularly to a kind of three-phase ac signal vasculum.
Background technology
In the early stage of development, generally use direct current sampling technique obtains the parameter value of electric system.And with power automation
Horizontal raising, the Control Technique of Microcomputer of digital intelligent grow rapidly, mainly make in electricity measuring instrument instruments and meters at present
It is completed with the mode of AC sampling.In broad terms, measured signal (voltage/current) is exactly transported to data and adopted by AC Data
Collect module, by mutual inductor (voltage transformer/current transformer), filter circuit, operational amplifier circuit processing after, which is sent
It is calculated to A/D modules and processor, so as to obtain the virtual value of virtual voltage/electric current, and then power can be calculated
The major parameters such as factor, active power, reactive power.AC Data is with its high-precision, real-time, inexpensive excellent spy
Property is widely used in electric power monitoring system.But the complexity of AC sampling equipment is higher at present, and stability also compares
It is poor.
Invention content
An embodiment of the present invention provides three-phase ac signal vasculums, can solve problems of the prior art.
The present invention provides a kind of three-phase ac signal vasculum, circuit board is installed in the vasculum, the circuit board
It is upper that there is mutual induction of voltage sample circuit, modulation circuit, Current Mutual Inductance sample circuit, current-to-voltage converting circuit, analog-to-digital conversion mould
Mains voltage signal is converted to -1.5V-1.5V, passed through by block, dsp processor and display screen, the mutual induction of voltage sample circuit
The voltage signal of -1.5V-1.5V is first converted to the voltage signal of 0V-3V by the modulation circuit；The Current Mutual Inductance sampling electricity
Road acquires the current signal of power grid, and the voltage signal of 0-3V is converted to by the current-to-voltage converting circuit；The modulation electricity
The voltage signal of road output and the voltage signal of current-to-voltage converting circuit output turn by analog-digital conversion circuit as described
Digital signal is changed to, and is transmitted to the dsp processor, the dsp processor is using half period integration sampling algorithm to simulation
Signal is shown the value of voltage and current by the display screen after being analyzed and processed.
Three-phase ac signal vasculum in the embodiment of the present invention with TMS320F28335 devices in order to control, uses three-phase alternating current
The method of sampling realizes acquires power network signal in real time, and voltage effective value is shown, and pass through setting by liquid crystal display LCD12864
Failure realizes the relay protection function of electric system.By testing the vasculum of the present invention using the voltage-controlled low-pass filtering electricity of second order
The advantages that road is with good stability and precision, simple in structure, at low cost, and stability is good.Synchronous generator can be used in encourage
Magnetically condition system, measuring instrument instrument, relay protection system etc. have good use value.
Description of the drawings
In order to illustrate more clearly about the embodiment of the present invention or technical scheme of the prior art, to embodiment or will show below
There is attached drawing needed in technology description to be briefly described, it should be apparent that, the accompanying drawings in the following description is only this
Some embodiments of invention, for those of ordinary skill in the art, without creative efforts, can be with
Other attached drawings are obtained according to these attached drawings.
Fig. 1 is the module connection diagram of circuit in three-phase ac signal vasculum provided in an embodiment of the present invention；
Fig. 2 is mutual induction of voltage sample circuit in Fig. 1, modulation circuit, Current Mutual Inductance sample circuit and Current Voltage conversion electricity
The schematic diagram on road；
Fig. 3 is the schematic diagram of power supply circuit in signal box.
Specific embodiment
Below in conjunction with the attached drawing in the embodiment of the present invention, the technical solution in the embodiment of the present invention is carried out clear, complete
Site preparation describes, it is clear that described embodiment is only part of the embodiment of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, those of ordinary skill in the art are obtained every other without making creative work
Embodiment shall fall within the protection scope of the present invention.
With reference to Fig. 1, a kind of three-phase ac signal vasculum is provided in the embodiment of the present invention, electricity is installed in the vasculum
Road plate has mutual induction of voltage sample circuit, modulation circuit, Current Mutual Inductance sample circuit, Current Voltage conversion electricity on the circuit board
Road, analog-to-digital conversion module, dsp processor and 12864 display screens.The mutual induction of voltage sample circuit is by mains voltage signal (Uu、
Uv、Uw) -1.5V-1.5V is converted to, the voltage signal of -1.5V-1.5V is first converted to by -3V-3V by the modulation circuit, then
Be converted to the voltage signal between 0V-3V；Current signal (the I of the Current Mutual Inductance sample circuit acquisition power gridu、Iv、Iw), warp
Cross the voltage signal that the current-to-voltage converting circuit is converted to 0-3V；The voltage signal of modulation circuit output and described
The voltage signal of current-to-voltage converting circuit output is converted to digital signal by analog-digital conversion circuit as described, and is transmitted to described
Dsp processor, the dsp processor by 12864 display screen show voltage and electricity after being analyzed and processed to analog signal
The value of stream.In order to test signal acquisition case, using three phase electric machine as load, relay adjusts three as protective loop
The voltage of phase motor realizes the defencive function to system with simulated failure process；It can be by changing algorithm collected electricity
Net signal calculates the active power and reactive power of load, and periphery increases compensation circuit, can to improve the power factor of load
Realize the Reactive-power control to load.
The model AD5725 of analog-to-digital conversion module described in the present embodiment, the model of the dsp processor
TMS320F28335, the model LCD12864 of 12864 display screen.
With reference to Fig. 2, the modulation circuit includes three operational amplifiers：U1A, U1B and U2A, three operational amplifiers
Model is LM358AD, and the mutual induction of voltage sample circuit includes voltage transformer T1, the model of voltage transformer T1
TV16E, power grid firewire are connected to one end of voltage transformer T1 primary sides, the other end connection electricity of primary side by resistance R27
Net zero curve, the secondary side both ends of voltage transformer T1 are parallel with resistance R13, while one end ground connection of secondary side, the other end pass through
The resistance R1 and R2 of series connection are connected to the in-phase input end of operational amplifier U1A, and in-phase input end also passes through capacitance C2 and connects simultaneously
Ground, inverting input are grounded by resistance R3, while are also passed through resistance R4 and be connected to the output, and pass through electricity between resistance R1 and R2
Hold the output terminal that C1 is connected to operational amplifier U1A, two power ends of operational amplifier U1A connect+5V and -5V electricity respectively
Source.Output terminal is connected to the in-phase input end of operational amplifier U1B by resistance R5, and in-phase input end also passes through resistance R9 simultaneously
The sliding end of swept resistance R10 is connected to, the both ends of swept resistance R10 are grounded and connect respectively+5V power supplys, operational amplifier U1B
Inverting input be grounded by resistance R6, while also pass through adjustable resistance R7 and be connected to output terminal, output terminal passes through resistance R8
It is connected to the in-phase input end of operational amplifier U2A, the inverting input of operational amplifier U2A is connected to defeated by resistance R11
Outlet, two power ends are respectively connected to+5V and -5V power supplys, and output terminal is connected to the pin 1 of plug P1 by resistance R12, defeated
Go out the voltage signal through ovennodulation.
The current-to-voltage converting circuit includes three operational amplifiers：U3A, U3B and U2B, three operational amplifiers
Model is LM358AD, and the Current Mutual Inductance sample circuit includes current transformer T2, the model of current transformer T2
TA12-200, power grid firewire are connected to one end of current transformer T2 primary sides, the other end connection grid zero line of primary side, electricity
The secondary side both ends of current transformer T2 are parallel with resistance R14, while one end ground connection of secondary side, resistance of the other end by series connection
R15 and R16 is connected to the in-phase input end of operational amplifier U3A, and in-phase input end also passes through capacitance C4 ground connection simultaneously, and reverse phase is defeated
Enter end to be grounded by resistance R17, while also pass through resistance R18 and be connected to the output, pass through capacitance C3 between resistance R15 and R16
The output terminal of operational amplifier U3A is connected to, two power ends of operational amplifier U3A connect+5V and -5V power supplys respectively.It is defeated
Outlet is connected to the in-phase input end of operational amplifier U3B by resistance R19, and in-phase input end also passes through resistance R25 companies simultaneously
The sliding end of swept resistance R26 is connected to, the both ends of swept resistance R26 are grounded and connect respectively+5V power supplys, operational amplifier U3B's
Inverting input is grounded by resistance R20, while is also passed through adjustable resistance R21 and be connected to output terminal, and output terminal passes through resistance R22
It is connected to the in-phase input end of operational amplifier U2B, the inverting input of operational amplifier U2B is connected to defeated by resistance R23
Outlet, output terminal are connected to the pin 2 of plug P1, voltage signal of the output by conversion by resistance R24.
With reference to Fig. 3, also there is power supply circuit in the vasculum on circuit board, which includes rectifier bridge D1 and four
A voltage-stablizer U4, U5, U6 and U7, the model KBP307 of rectifier bridge D1, the model of voltage-stablizer U4 in the present embodiment
L7812CV, the model L7905CV of the model L7805CV of voltage-stablizer U5 and U6, voltage-stablizer U7.220V electric mains pass through
Two-way transformer is converted to 15V alternating currents, and two output terminals of 15V AC powers are connected to two inputs of rectifier bridge D1
End, one of them of two output terminals of rectifier bridge D1 are connected to the input terminal of voltage-stablizer U4, another output terminal is connected to voltage stabilizing
The input terminal of device U7, the ground terminal ground connection of voltage-stablizer U4, while input terminal is grounded by capacitance C5, output terminal is connected to voltage-stablizer
The input terminal of U5 is grounded also by capacitance C6, C7 and C8 in parallel, and the ground terminal ground connection of voltage-stablizer U5, output terminal is connected to slotting
The pin 3 of head P2, the 5V voltages that output voltage stabilizing obtains, the output terminal of voltage-stablizer U4 are connected to the input terminal of voltage-stablizer U6, simultaneously
Also it is connected to the pin 1 of plug P2, exports 12V voltages, the resistance R28 and light-emitting diodes that the input terminal of voltage-stablizer U6 passes through series connection
Pipe D2 is grounded, and output terminal is connected to the pin 2 of plug P2, exports 5V voltages, while ground terminal is grounded, ground terminal and output terminal it
Between be connected with the capacitance C13 and resistance R29 of series connection and light emitting diode D3.Voltage-stablizer U5 ground terminal ground connection, output terminal and
The resistance R30 of capacitance C9 and series connection and the ground terminal ground connection of light emitting diode D4, voltage-stablizer U7, input are connected between ground terminal
End is connected to the pin 4 of plug P2, output -5V voltages, while output terminal by capacitance C10 and C11 ground connection in parallel, output terminal
The capacitance C12 and resistance R31 of series connection and light emitting diode D5 is connected between ground terminal.12V, 5V of plug P2 outputs
It is used to provide the operating voltage of bias voltage and relay with -5V voltages.
The dsp processor handles the signal of input using half period integration sampling algorithm, which is specially：
If u=UmSinwt,
Then
Integral area UuIt is unrelated with the initial phase angle α for integrating starting point, arbitrary half period (π~π can be obtained according to symmetry
+ α) area and positive half cycle area equation, area can be obtained with Rectangular Method approximation：
N be half period sampling number, TsFor sampling time interval, uiValue for the i-th sampled point.
The virtual value of electric current can similarly obtain：
Remaining two-phase can similarly obtain：
Although preferred embodiments of the present invention have been described, but those skilled in the art once know basic creation
Property concept, then additional changes and modifications may be made to these embodiments.So appended claims be intended to be construed to include it is excellent
It selects embodiment and falls into all change and modification of the scope of the invention.
Obviously, various changes and modifications can be made to the invention without departing from essence of the invention by those skilled in the art
God and range.In this way, if these modifications and changes of the present invention belongs to the range of the claims in the present invention and its equivalent technologies
Within, then the present invention is also intended to include these modifications and variations.
Claims (6)
1. a kind of three-phase ac signal vasculum, which is characterized in that be equipped with circuit board in the vasculum, have on the circuit board
Have mutual induction of voltage sample circuit, modulation circuit, Current Mutual Inductance sample circuit, current-to-voltage converting circuit, analog-to-digital conversion module,
Dsp processor and display screen, mains voltage signal is converted to -1.5V-1.5V by the mutual induction of voltage sample circuit, by described
The voltage signal of -1.5V-1.5V is first converted to the voltage signal of 0V-3V by modulation circuit；The Current Mutual Inductance sample circuit is adopted
Collect the current signal of power grid, the voltage signal of 0-3V is converted to by the current-to-voltage converting circuit；The modulation circuit is defeated
The voltage signal gone out and the voltage signal of current-to-voltage converting circuit output are converted to by analog-digital conversion circuit as described
Digital signal, and the dsp processor is transmitted to, the dsp processor is using half period integration sampling algorithm to analog signal
The value of voltage and current is shown after being analyzed and processed by the display screen.
2. three-phase ac signal vasculum as described in claim 1, which is characterized in that the model of the analog-to-digital conversion module
AD5725, the model TMS320F28335 of the dsp processor, the model LCD12864 of the display screen.
3. three-phase ac signal vasculum as described in claim 1, which is characterized in that the modulation circuit includes three operations
Amplifier：U1A, U1B and U2A, the mutual induction of voltage sample circuit include voltage transformer T1, and power grid firewire passes through resistance R27
One end of voltage transformer T1 primary sides is connected to, the other end connection grid zero line of primary side, voltage transformer T1's is secondary
Side both ends are parallel with resistance R13, while one end ground connection of secondary side, resistance R1 and R2 of the other end by series connection are connected to operation
The in-phase input end of amplifier U1A, in-phase input end also pass through capacitance C2 ground connection simultaneously, and inverting input is connect by resistance R3
Ground, while also pass through resistance R4 and be connected to the output, it is connected to operational amplifier U1A's by capacitance C1 between resistance R1 and R2
Output terminal, two power ends of operational amplifier U1A connect+5V and -5V power supplys respectively, and output terminal is connected to fortune by resistance R5
The in-phase input end of amplifier U1B is calculated, in-phase input end also passes through the sliding end that resistance R9 is connected to swept resistance R10 simultaneously,
The both ends of swept resistance R10 are grounded and connect respectively+5V power supplys, and the inverting input of operational amplifier U1B is grounded by resistance R6,
Also passing through adjustable resistance R7 is connected to output terminal simultaneously, and output terminal is connected to the same mutually defeated of operational amplifier U2A by resistance R8
Enter end, the inverting input of operational amplifier U2A is connected to output terminal by resistance R11, and two power ends are respectively connected to+5V
With -5V power supplys, output terminal is connected to the pin 1 of plug P1 by resistance R12, exports the voltage signal through ovennodulation.
4. three-phase ac signal vasculum as claimed in claim 3, which is characterized in that the current-to-voltage converting circuit includes
Three operational amplifiers：U3A, U3B and U2B, the Current Mutual Inductance sample circuit include current transformer T2, the connection of power grid firewire
In one end of current transformer T2 primary sides, the other end connection grid zero line of primary side, the secondary side two of current transformer T2
End is parallel with resistance R14, while one end ground connection of secondary side, resistance R15 and R16 of the other end by series connection are connected to operation and put
The in-phase input end of big device U3A, in-phase input end also pass through capacitance C4 ground connection simultaneously, and inverting input is grounded by resistance R17,
It also passes through resistance R18 simultaneously to be connected to the output, is connected to operational amplifier U3A's by capacitance C3 between resistance R15 and R16
Output terminal, two power ends of operational amplifier U3A connect+5V and -5V power supplys respectively；Output terminal is connected to by resistance R19
The in-phase input end of operational amplifier U3B, in-phase input end also pass through the slip that resistance R25 is connected to swept resistance R26 simultaneously
End, the both ends of swept resistance R26 are grounded and connect respectively+5V power supplys, and the inverting input of operational amplifier U3B passes through resistance R20
Ground connection, while also pass through adjustable resistance R21 and be connected to output terminal, output terminal is connected to operational amplifier U2B's by resistance R22
In-phase input end, the inverting input of operational amplifier U2B are connected to output terminal by resistance R23, and output terminal passes through resistance R24
It is connected to the pin 2 of plug P1, voltage signal of the output by conversion.
5. three-phase ac signal vasculum as claimed in claim 4, which is characterized in that also have on circuit board in the vasculum
There is power supply circuit, which includes rectifier bridge D1 and four voltage-stablizers U4, U5, U6 and U7, and 220V electric mains are by double
Road transformer is converted to 15V alternating currents, and two output terminals of 15V AC powers are connected to two inputs of rectifier bridge D1
End, one of them of two output terminals of rectifier bridge D1 are connected to the input terminal of voltage-stablizer U4, another output terminal is connected to voltage stabilizing
The input terminal of device U7, the ground terminal ground connection of voltage-stablizer U4, while input terminal is grounded by capacitance C5, output terminal is connected to voltage-stablizer
The input terminal of U5 is grounded also by capacitance C6, C7 and C8 in parallel, and the ground terminal ground connection of voltage-stablizer U5, output terminal is connected to slotting
The pin 3 of head P2, the 5V voltages that output voltage stabilizing obtains, the output terminal of voltage-stablizer U4 are connected to the input terminal of voltage-stablizer U6, simultaneously
Also it is connected to the pin 1 of plug P2, exports 12V voltages, the resistance R28 and light-emitting diodes that the input terminal of voltage-stablizer U6 passes through series connection
Pipe D2 is grounded, and output terminal is connected to the pin 2 of plug P2, exports 5V voltages, while ground terminal is grounded, ground terminal and output terminal it
Between be connected with the capacitance C13 and resistance R29 of series connection and light emitting diode D3；Voltage-stablizer U5 ground terminal ground connection, output terminal and
The resistance R30 of capacitance C9 and series connection and the ground terminal ground connection of light emitting diode D4, voltage-stablizer U7, input are connected between ground terminal
End is connected to the pin 4 of plug P2, output -5V voltages, while output terminal by capacitance C10 and C11 ground connection in parallel, output terminal
The capacitance C12 and resistance R31 of series connection and light emitting diode D5 is connected between ground terminal.
6. three-phase ac signal vasculum as claimed in claim 5, which is characterized in that the operational amplifier U1A, U1B,
The model of U2A, U2B, U3A and U3B are LM358AD, the model TV16E of the voltage transformer T1, the Current Mutual Inductance
The model L7812CV of the model KBP307 of the model TA12-200 of device T2, rectifier bridge D1, voltage-stablizer U4, voltage-stablizer U5
With the model L7805CV of U6, the model L7905CV of voltage-stablizer U7.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201810013678.1A CN108152635A (en) | 2018-01-08 | 2018-01-08 | A kind of three-phase ac signal vasculum |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810013678.1A CN108152635A (en) | 2018-01-08 | 2018-01-08 | A kind of three-phase ac signal vasculum |
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| CN101227090B (en) * | 2007-12-03 | 2011-05-04 | 天津理工大学 | Maximum power tracking controller for photovoltaic power generation based on digital signal processor |
| CN201637803U (en) * | 2010-04-23 | 2010-11-17 | 哈尔滨国力电气有限公司 | Portable failure data recorder |
| US20120153934A1 (en) * | 2010-12-16 | 2012-06-21 | Hubei Shengjia Electric Apparatus Co., Ltd. | Voltage and current sampling device |
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