CN202676803U - Low-voltage high-current magnetic field simulation display device of distribution network - Google Patents
Low-voltage high-current magnetic field simulation display device of distribution network Download PDFInfo
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- CN202676803U CN202676803U CN 201220345115 CN201220345115U CN202676803U CN 202676803 U CN202676803 U CN 202676803U CN 201220345115 CN201220345115 CN 201220345115 CN 201220345115 U CN201220345115 U CN 201220345115U CN 202676803 U CN202676803 U CN 202676803U
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Abstract
The utility model provides a low-voltage high-current magnetic field simulation display device of a distribution network, relating to the detection of magnetic circuit saturation high current of an electric power system. The device comprises a distribution network low-voltage high current generating circuit, a low-voltage high current detector, a 5V regulated power supply, an A/D converter, a control single chip microcomputer and a display. The device is capable of both generating high current under low voltage of the distribution network and simulating and displaying the high current in the display of the device and is an intelligent high-current magnetic field simulation display device which is convenient to carry, simple to operate, low in price and high in precision.
Description
Technical field
The technical solution of the utility model relates to the detection of the saturated large electric current of magnetic circuit of electric system, specifically power distribution network low-voltage, high-current magnetic simulation display device.
Background technology
At present, generating set is sent using by the electromagnetic equipment distribution more than 90% of electric energy.Electromagnetic equipment is used widely the normal operation of its serviceability and reliability direct relation national product in the safe distribution in the fields such as industry, agricultural, communications and transportation, national defence, science and education, Wen Wei, finance, commerce, tourist service and people's lives.But the fast development of and electric system more and more higher to the requirement of power supply quality along with the development of national economy causes the phenomenon of fault also more and more because magnetic circuit is saturated.When the magnetization of ferromagnetic material reaches capacity, when making the magnetic saturation of part magnetic circuit, can produce local large electric current electromagnetic equipment is burnt out, thereby affect normal power supply.Therefore needing research and development a kind of can (be three-phase 220V in power distribution network low pressure, lower with) under carry out the intelligent large current field analog display unit that simulation shows, easy to carry, simple to operate, cheap and measuring accuracy is high of large current field, with the important tool as the magnetic circuit fault detect of modern power systems, this be the saturated checking of great current technical development of magnetic circuit in the urgent need to.
The utility model content
Technical problem to be solved in the utility model is: power distribution network low-voltage, high-current magnetic simulation display device is provided, this device can not only produce large electric current under power distribution network low pressure, and can in the display of this device, simulate this large electric current of demonstration, be the large current field analog display unit of a kind of intellectuality easy to carry, simple to operate, cheap and that measuring accuracy is high.
The utility model solves this technical problem the technical scheme that adopts: power distribution network low-voltage, high-current magnetic simulation display device, its formation comprise that the power distribution network low-voltage, high-current produces circuit, low-voltage, high-current detecting device, 5V stabilized voltage supply, A/D converter, control single chip computer and display; Described power distribution network low-voltage, high-current produces circuit by autotransformer T
1, exciter transformer T
2Summation current transformer T
3Former limit consist of, the order of connection of this three part is followed successively by: autotransformer T
1Secondary meet exciter transformer T
2Former limit, exciter transformer T
2Secondary meet current transformer T
3Former limit; Described low-voltage, high-current detecting device is by current transformer T
3Secondary and measuring resistance R
2Form current transformer T
3Secondary and measuring resistance R
2In parallel; Described A/D converter is comprised of ADC0809 chip and SUN7474 chip; The integrated connection mode of power distribution network low-voltage, high-current magnetic simulation display device is: the power distribution network low-voltage, high-current produces between circuit, low-voltage, high-current detecting device, 5V stabilized voltage supply, A/D converter, control single chip computer and display six parts and connects by wire, wherein the current transformer T of low-voltage, high-current detecting device
3Secondary and measuring resistance R
2After the parallel connection, the output of one end links to each other with ADC0809 chip input end as sampled signal, other end ground connection, control single chip computer carries out assignment to the address input line of ADC0809 chip, the output of ADC0809 chip is as the input of control single chip computer, the SUN7474 chip links to each other with the address latch port ALE of ADC0809 chip, and the voltage source of 5V stabilized voltage supply is connected feeder ear and is connected by wire with A/D converter, control single chip computer and display.
Above-mentioned power distribution network low-voltage, high-current magnetic simulation display device, described power distribution network low-voltage, high-current produces the exciter transformer T in the circuit
2The former limit number of turn be 2933 circles, secondary is the large electric current copper cash of a circle, its long for 1.7147m, cross-sectional area be 120mm
2, parameter is elected 75mV/300A as.
Above-mentioned power distribution network low-voltage, high-current magnetic simulation display device, described measuring resistance R
2Resistance be 1 Ω.
Above-mentioned power distribution network low-voltage, high-current magnetic simulation display device, described 5V stabilized voltage supply is comprised of chip LM22676 and peripheral circuit thereof, the connected mode of its chips LM22676 and peripheral circuit is as follows: the 7th pin VIN of chip LM22676 is through input capacitance C1 and C2 earth, the 5th pin Enable Pin EN of chip LM22676 connects high level, the 6th pin GND ground connection of chip LM22676, the 2nd and 3 pin NC of chip LM22676 are unsettled, meet bootstrap capacitor C3 between the 1st pin BOOT of chip LM22676 and the 8th pin SW, SW is again through voltage stabilizing diode D1 ground connection, the 8th pin SW output termination inductance L 1 one ends of chip LM22676, the L1 other end and through divider resistance R1 and R2 series connection ground connection and capacitor C 4 ground connection, the 4th pin FB of chip LM22676 is connected between R1 and the R2.
Above-mentioned power distribution network low-voltage, high-current magnetic simulation display device, described control single chip computer adopts the 80C51 single-chip microcomputer.
Above-mentioned power distribution network low-voltage, high-current magnetic simulation display device, described display is LED charactron display, its circuit is comprised of P1, P2 mouth and the chip SR420561K of 80C51 single-chip microcomputer.
Above-mentioned power distribution network low-voltage, high-current magnetic simulation display device, wherein involved circuit, element and connected mode thereof all are that those skilled in the art are known, used components and parts can be by commercially available.
The beneficial effects of the utility model are: the outstanding substantive distinguishing features that the utility model power distribution network low-voltage, high-current magnetic simulation display device has is: owing to being provided with by autotransformer T in the utility model power distribution network low-voltage, high-current magnetic simulation display device
1, exciter transformer T
2Summation current transformer T
3The power distribution network low-voltage, high-current that consists of of former limit produce circuit, the saturated principle of this circuit application electromagnetism is as autotransformer T
1When electric current increased, meeting was so that exciter transformer T
2The ironcore choke magnetic circuit reach capacity, thereby produce large electric current; Simultaneously, by current transformer T
3Secondary and measuring resistance R
2The low-voltage, high-current detecting device that forms can be converted to voltage signal to current signal, changes digital signal into through A/D converter again; Main control singlechip 80C51 finishes the above-mentioned digital signal of input is processed, and shows the result by display.The remarkable advantage that the utility model power distribution network low-voltage, high-current magnetic simulation display device has and progress are: the operating voltage of this device is power distribution network low pressure 220V, so the scope of application is wider; Owing to having added corresponding control single chip computer, having realized robotization and the intellectuality of control; The current measuring range of this device is wide, and measurement range is 0.0～300A, and maximum current can reach 300A, and precision is high, and antijamming capability is strong.The utility model device can not only produce large electric current under the power distribution network three-phase voltage, and can in the display of this device, simulate this large current field of demonstration, be the large current field analog display unit of a kind of intellectuality easy to carry, simple to operate, cheap, that measuring accuracy is high.To further prove the beneficial effect of the utility model device in the following example.
Description of drawings
Below in conjunction with drawings and Examples the utility model is further specified.
Fig. 1 is the formation block diagram of the utility model power distribution network low-voltage, high-current magnetic simulation display device.
Fig. 2 is that the power distribution network low-voltage, high-current in the utility model power distribution network low-voltage, high-current magnetic simulation display device produces circuit diagram.
Fig. 3 is the forming circuit figure of the 5V stabilized voltage supply in the utility model power distribution network low-voltage, high-current magnetic simulation display device.
Fig. 4 is the formation schematic diagram of the A/D converter in the utility model power distribution network low-voltage, high-current magnetic simulation display device.
Fig. 5 is control single chip computer in the utility model power distribution network low-voltage, high-current magnetic simulation display device and the main process chip circuit diagram of display.
Fig. 6 is the forming circuit figure of the display in the utility model power distribution network low-voltage, high-current magnetic simulation display device.
Fig. 7 is the connecting circuit schematic diagram of the main part in the utility model power distribution network low-voltage, high-current magnetic simulation display device.
Among the figure, 1. autotransformer T
1, 2. exciter transformer T
2, 3. current transformer T
3, the 4.ADC0809 chip.
Embodiment
Fig. 1 illustrates power distribution network low-voltage, high-current magnetic simulation display device of the present utility model, formed by hardware components and software section, wherein, hardware components comprises that the power distribution network low-voltage, high-current produces circuit, low-voltage, high-current detecting device, 5V stabilized voltage supply, A/D converter, control single chip computer and display, its connected mode is that large current generating circuit, low-voltage, high-current detecting device, A/D converter, control single chip computer, display connect successively, and the voltage source of 5V stabilized voltage supply is connected feeder ear and is connected by wire with A/D converter, control single chip computer and display; Software section is the running program of governor circuit, is comprised of control master routine, data processing subroutine and display subroutine.
The empty frame demonstration in Fig. 2 left side, the power distribution network low-voltage, high-current in the utility model power distribution network low-voltage, high-current magnetic simulation display device produces circuit by autotransformer T
11, exciter transformer T
22 summation current transformer T
33 former limit consists of, and the order of connection of this three part is followed successively by: autotransformer T
11 secondary meets exciter transformer T
22 former limit, exciter transformer T
22 secondary meets current transformer T
33 former limit.In addition, autotransformer T
11 former edge joint power distribution network low pressure 220V, its secondary voltage changes in 0～220V voltage range, autotransformer T
11 couple of exciter transformer T
22 power; The large electric current that this power distribution network low-voltage, high-current generation circuit sends is through current transformer T
33 and measuring resistance R
2Convert voltage signal to, this signal is as sampled signal input chip ADC0809.
The empty frame demonstration in Fig. 2 right side, the low-voltage, high-current detecting device in the utility model power distribution network low-voltage, high-current magnetic simulation display device is by current transformer T
33 secondary and measuring resistance R
2Consist of current transformer T
33 secondary and measuring resistance R
2Parallel connection, measuring resistance R wherein
2An end power distribution network low-voltage, high-current produced the current signal that circuit sends be converted to voltage signal, and with this voltage signal as sampled signal by measuring resistance R
2An end be input to the input end IN3 of ADC08095, measuring resistance R
2Other end ground connection GND.
The forming circuit of the 5V stabilized voltage supply in the utility model power distribution network low-voltage, high-current magnetic simulation display device that shows embodiment illustrated in fig. 3 is by LM22676 chip, capacitor C
1, capacitor C
2, capacitor C
3, capacitor C
4, resistance R
1, resistance R
2, inductance L
1With voltage stabilizing diode D
1Form.Wherein, capacitor C
1Positive pole and capacitor C
2Positive pole jointly be connected on the 7th pin VIN of LM22676 the equal ground connection GND of its negative pole, and VIN connects high level; The 6th pin ground connection GND of LM22676 chip, the 5th pin EN of LM22676 chip connects high level, the 1st pin BOOT of LM22676 chip connects the positive pole of capacitor C3, and the negative pole of C3 meets LM22676 chip the 8th pin SW and pass through stabilivolt D1 ground connection, another termination inductance L of LM22676 chip the 8th pin SW
1One end, inductance L
1The other end is through divider resistance R
1With R
2Series connection ground connection, simultaneously inductance L
1The other end and capacitor C 4 positive poles join and are connected to the voltage output end of this power supply, in addition capacitor C
4Minus earth; LM22676 chip the 4th pin FB is connected on resistance R
1And resistance R
2Intermediate contact on.Like this, resistance R
1One end output voltage is stable 5V voltage, has guaranteed the steady operation 5V voltage of this power distribution network low-voltage, high-current magnetic simulation display device, and its effect is to provide stable operating voltage for A/D converter, control single chip computer and display.The parameter of each electronic component is as follows: C
1=22 μ F, C
2=2.2 μ F, C
3=10nF, C
4=120 μ F, R
1=4.7K Ω, R
2=0.828K Ω, L
1=8.2 μ H, voltage stabilizing diode D
1Adopting the voltage stabilizing value is the 1N4756 of 45V.
The SUN7474 chip of the A/D converter in the utility model power distribution network low-voltage, high-current magnetic simulation display device on the right of the ADC0809 chip on this figure left side and this figure that show embodiment illustrated in fig. 4 forms.When single-chip microcomputer 80C51 to address input line ADD-A, the ADD-B of the 23rd, 24 and 25 pins of A/D converter ADC0809 and ADD-C respectively assignment 1,1,0 the time, the analog input of gating IN3.A/D converter is with the measuring resistance R in the low-voltage, high-current detecting device
2The end analog signal conversion that is input to the input end IN3 of ADC08095 be digital signal, and export single-chip microcomputer 80C51 single-chip microcomputer to and do next step processing.
Fig. 5 shows that used control single chip computer is the circuit diagram of 80C51 single-chip microcomputer in the utility model power distribution network low-voltage, high-current magnetic simulation display device, the 80C51 single-chip microcomputer is processed the digital signal of being imported into by A/D converter, and the data that obtain after will processing are delivered to display.
Fig. 6 shows that the display in the utility model power distribution network low-voltage, high-current magnetic simulation display device is made of P1, the P2 mouth of the single-chip microcomputer institute that links to each other with the pin of chip SR420561K, shows the measurement current value data that obtain after being processed by the 80C51 single-chip microcomputer.The P1 of single-chip microcomputer comprises P1.0～P1.7, is connected with pin a, b, c, d, e, f, g and the Dp of chip SR420561K respectively; P2 comprises P2.0～P2.3, is connected with pin S1, S2, S3 and the S4 of chip SR420561K with triode by 500 Ω resistance respectively.
Fig. 7 shows the connecting circuit of the main part in the utility model power distribution network low-voltage, high-current magnetic simulation display device, wherein A dotted line frame partly produces circuit for the power distribution network low-voltage, high-current, B dotted line frame partly is the low-voltage, high-current detecting device, C dotted line frame partly is A/D converter, D dotted line frame partly is control single chip computer 80C51 single-chip microcomputer, and E dotted line frame partly is display.Its connected mode is: power distribution network low-voltage, high-current generation circuit, checking of great current circuit, A/D change-over circuit, control single chip computer 80C51 single-chip microcomputer are connected with display and are connected.Low-voltage, high-current produces the input termination power distribution network low pressure 220V of circuit, its output terminal links to each other with the low-voltage, high-current detecting device, the low-voltage, high-current detecting device converts current signal to voltage signal, the input end of the voltage signal input a/d converter chip ADC0809 of low-voltage, high-current detecting device output, become digital signal by the A/D converter analog-to-digital conversion, the A/D converter output digit signals is to the input end of control single chip computer 80C51 single-chip microcomputer, the data communication device that will obtain after control single chip computer 80C51 single-chip microcomputer will be processed crosses P1 and the P2 mouth is sent to display, and control display device SR420561K shows the measurement current value data that obtain.
According to above-mentioned Fig. 2～Fig. 7 configuration and the used power distribution network low-voltage, high-current magnetic simulation display device of installation the present embodiment, wherein, exciter transformer T
22 secondary is the large electric current copper cash of a circle, like this as autotransformer T
1When 1 electric current increased, meeting was so that exciter transformer T
2The magnetic circuit of 2 coils reaches capacity, by the saturated relevant knowledge of magnetic circuit as can be known, and exciter transformer T
2Can produce large distortion current in 2 the coil, this distortion current can reach more than 300 amperes.Exciter transformer T
2The large electric current copper cash of 2 secondary is long to be that 1.7147m, cross-sectional area are 120mm
20, parameter is elected 75mV/300A as.According to the transformer voltage ratio formula
, get exciter transformer T
22 the former limit number of turn
This moment, the power of this device was: P=300A * 75mV=22.5W.The capacity that this power parameter can reach power supply commonly used limits, and guarantees the operation that power-supply unit can be stable.Therefore, it is reasonable in design that the large current field of the utility model power distribution network low-voltage, high-current magnetic simulation display device produces, and is easy to the measuring equipment of routine adaptively, and its electric current can reach more than the 300A.Here Application standard resistance R
2Resistance be 1 Ω, guarantee measuring accuracy.
Carry out power distribution network low-voltage, high-current magnetic simulation with this device and show, its operating process and result are:
Check current transformer before the experiment beginning, in case the secondary open circuit has an accident.Connect three-phase alternating-current supply, regulate autotransformer T
1, make autotransformer T
1The output voltage of secondary is 220V.The 5V steady voltage source provides stable operating voltage to A/D converter, control single chip computer and display.The 80C51 single-chip microcomputer carries out the setting of initialization and input channel, its I/O mouth P3.4, P3.5 and P3.6 to address input line ADD-A, the ADD-B of ADC0809 chip and ADD-C respectively assignment be 1,1,0 o'clock, the IN3 analog input of gating ADC0809 chip, the SUN7474 chip is as the CLK signal frequency generator of ADC0809 chip.The analog signal conversion that the ADC0809 chip will be inputted IN3 is the digital signal that the 80C51 single-chip microcomputer can be identified, the 80C51 single-chip microcomputer is by I/O mouth P0.0～P0.7 receive data, and calling data processes subroutine the data that gather processed, and calls simultaneously display subroutine result is delivered to group of four figures display SR420561K chip by I/O mouth P1.0～P1.7, P2.0～P2.3.
The result: nixie display shows that the result is 299.3A, and error is 0.23%＜0.5%, in the error allowed band.
Remove when being operation the autotransformer T in the power distribution network low-voltage, high-current generation circuit
1Secondary voltage transfer to outside the 127V, the used power distribution network low-voltage, high-current magnetic simulation display device of the present embodiment and other operating process are with embodiment 1.
The result: nixie display shows that the result is 173.8A, and error is 0.35%＜0.5%, in the error allowed band.
Claims (6)
1. power distribution network low-voltage, high-current magnetic simulation display device is characterized in that: its formation comprises that the power distribution network low-voltage, high-current produces circuit, low-voltage, high-current detecting device, 5V stabilized voltage supply, A/D converter, control single chip computer and display; Described power distribution network low-voltage, high-current produces circuit by autotransformer T
1, exciter transformer T
2Summation current transformer T
3Former limit consist of, the order of connection of this three part is followed successively by: autotransformer T
1Secondary meet exciter transformer T
2Former limit, exciter transformer T
2Secondary meet current transformer T
3Former limit; Described low-voltage, high-current detecting device is by current transformer T
3Secondary and measuring resistance R
2Form current transformer T
3Secondary and measuring resistance R
2In parallel; Described A/D converter is comprised of ADC0809 chip and SUN7474 chip; The integrated connection mode of power distribution network low-voltage, high-current magnetic simulation display device is: the power distribution network low-voltage, high-current produces between circuit, low-voltage, high-current detecting device, 5V stabilized voltage supply, A/D converter, control single chip computer and display six parts and connects by wire, wherein the current transformer T of low-voltage, high-current detecting device
3Secondary and measuring resistance R
2After the parallel connection, the output of one end links to each other with ADC0809 chip input end as sampled signal, other end ground connection, control single chip computer carries out assignment to the address input line of ADC0809 chip, the output of ADC0809 chip is as the input of control single chip computer, the SUN7474 chip links to each other with the address latch port ALE of ADC0809 chip, and the voltage source of 5V stabilized voltage supply is connected feeder ear and is connected by wire with A/D converter, control single chip computer and display.
2. described power distribution network low-voltage, high-current magnetic simulation display device according to claim 1, it is characterized in that: described power distribution network low-voltage, high-current produces the exciter transformer T in the circuit
2The former limit number of turn be 2933 circles, secondary is the large electric current copper cash of a circle, its long for 1.7147m, cross-sectional area be 120mm
2, parameter is elected 75mV/300A as.
3. described power distribution network low-voltage, high-current magnetic simulation display device according to claim 1 is characterized in that: described measuring resistance R
2Resistance be 1 Ω.
4. described power distribution network low-voltage, high-current magnetic simulation display device according to claim 1, it is characterized in that: described 5V stabilized voltage supply is comprised of chip LM22676 and peripheral circuit thereof, the connected mode of its chips LM22676 and peripheral circuit is as follows: the 7th pin VIN of chip LM22676 is through input capacitance C1 and C2 earth, the 5th pin Enable Pin EN of chip LM22676 connects high level, the 6th pin GND ground connection of chip LM22676, the 2nd and 3 pin NC of chip LM22676 are unsettled, meet bootstrap capacitor C3 between the 1st pin BOOT of chip LM22676 and the 8th pin SW, SW is again through voltage stabilizing diode D1 ground connection, the 8th pin SW output termination inductance L 1 one ends of chip LM22676, the L1 other end and through divider resistance R1 and R2 series connection ground connection and capacitor C 4 ground connection, the 4th pin FB of chip LM22676 is connected between R1 and the R2.
5. described power distribution network low-voltage, high-current magnetic simulation display device according to claim 1, it is characterized in that: described control single chip computer adopts the 80C51 single-chip microcomputer.
6. described power distribution network low-voltage, high-current magnetic simulation display device according to claim 1, it is characterized in that: described display is LED charactron display, its circuit is comprised of P1, P2 mouth and the chip SR420561K of 80C51 single-chip microcomputer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220345115 CN202676803U (en) | 2012-07-18 | 2012-07-18 | Low-voltage high-current magnetic field simulation display device of distribution network |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220345115 CN202676803U (en) | 2012-07-18 | 2012-07-18 | Low-voltage high-current magnetic field simulation display device of distribution network |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202676803U true CN202676803U (en) | 2013-01-16 |
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ID=47497701
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201220345115 Expired - Fee Related CN202676803U (en) | 2012-07-18 | 2012-07-18 | Low-voltage high-current magnetic field simulation display device of distribution network |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN202676803U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102759656A (en) * | 2012-07-18 | 2012-10-31 | 河北工业大学 | Power distribution network low-voltage large-current magnetic field simulation display device |
| CN104076196A (en) * | 2014-06-27 | 2014-10-01 | 南京城市职业学院 | High-precision direct current Hall digit sensing system and current measuring method |
-
2012
- 2012-07-18 CN CN 201220345115 patent/CN202676803U/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102759656A (en) * | 2012-07-18 | 2012-10-31 | 河北工业大学 | Power distribution network low-voltage large-current magnetic field simulation display device |
| CN102759656B (en) * | 2012-07-18 | 2014-11-05 | 河北工业大学 | Power distribution network low-voltage large-current magnetic field simulation display device |
| CN104076196A (en) * | 2014-06-27 | 2014-10-01 | 南京城市职业学院 | High-precision direct current Hall digit sensing system and current measuring method |
| CN104076196B (en) * | 2014-06-27 | 2017-02-15 | 南京城市职业学院 | High-precision direct current Hall digit sensing system and current measuring method |
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|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20130116 Termination date: 20150718 |
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| EXPY | Termination of patent right or utility model |