CN220105134U - Integrated galvanic isolation electronic sensor - Google Patents
Integrated galvanic isolation electronic sensor Download PDFInfo
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- CN220105134U CN220105134U CN202321438661.3U CN202321438661U CN220105134U CN 220105134 U CN220105134 U CN 220105134U CN 202321438661 U CN202321438661 U CN 202321438661U CN 220105134 U CN220105134 U CN 220105134U
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- isolation
- amplifying circuit
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- 238000002955 isolation Methods 0.000 title claims abstract description 42
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims abstract description 43
- 229910052802 copper Inorganic materials 0.000 claims abstract description 42
- 239000010949 copper Substances 0.000 claims abstract description 42
- 230000000087 stabilizing effect Effects 0.000 claims abstract description 16
- 238000005070 sampling Methods 0.000 claims description 19
- 238000004806 packaging method and process Methods 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 abstract description 9
- 230000000694 effects Effects 0.000 abstract description 8
- 230000005540 biological transmission Effects 0.000 abstract description 6
- 238000009434 installation Methods 0.000 abstract description 3
- 239000000463 material Substances 0.000 abstract description 3
- 230000009466 transformation Effects 0.000 abstract description 3
- HPDFFVBPXCTEDN-UHFFFAOYSA-N copper manganese Chemical compound [Mn].[Cu] HPDFFVBPXCTEDN-UHFFFAOYSA-N 0.000 description 9
- 239000011162 core material Substances 0.000 description 3
- 230000003321 amplification Effects 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 2
- 239000004020 conductor Substances 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000003199 nucleic acid amplification method Methods 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 229910000881 Cu alloy Inorganic materials 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000005672 electromagnetic field Effects 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 230000020169 heat generation Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
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- Measurement Of Current Or Voltage (AREA)
Abstract
The utility model discloses an integrated galvanic isolation electronic sensor, which belongs to the technical field of electric power automation transmission and transformation alternating current heavy current collection, and comprises copper bars; the signal amplifying circuit is used for amplifying the voltage signals acquired on the copper bars; an isolation output circuit for isolating the signal of the signal amplifying circuit; the power supply voltage stabilizing circuit is used for providing the power supply voltage which is subjected to isolation treatment for the signal amplifying circuit to work; the copper bar is of an integral structure, the electric control module is directly arranged on the copper bar main body, the module fixing point is the acquisition signal input end, the copper bar is efficient and energy-saving, the working temperature rise is reduced, the volume is small, the material cost is saved, the production cost is low, the installation space is reduced, the energy-saving effect is obvious, and compared with a shunt product with the same current specification volume, the energy-saving effect 97.34% and the temperature reduction value are more than 116.8 degrees.
Description
Technical Field
The utility model belongs to the technical field of power automation power transmission and transformation alternating current heavy current collection, and particularly relates to an integrated current isolation electronic sensor.
Background
The current large current collecting elements are an alternating current transformer and a current shunt, various loads are considered in an actual conveying line, and rated current of about 10 times is needed for some loads during starting, so that 12 times of current can be measured by the conveying line, for example, 630A class line collecting current is 630 x 12 = 7560A, and the alternating current transformer or the current shunt selected at the moment is of 6300A class;
the following analysis of defects in operation of the AC transformer and current shunt of 6300A current class
1. The ac transformer has the following defects:
1. the volume is large: the alternating current transformer adopts a transformation ratio mode of input 6300A and output 5A, coil current is 5A turns 1260 turns, in order to ensure that the output is linear unsaturated when large current is input, a magnetic core with large cross section area is adopted, and a coarse enamelled wire meeting the requirement of 5A current is wound, so that the volume of a finished product is large, and the size of the finished product reaches 280 x 210 x 60 (mm);
2. the precision is 5%, if the higher precision is to be achieved, the performance of the magnetic core material is to be improved, the number of turns is to be increased, and the production cost is to be increased and the volume is to be larger;
3. because the output is in a 5A current form, the output cannot be directly recognized and used by the computer protection equipment, and the output is changed into a weak current or voltage which can be recognized by the computer protection equipment after secondary treatment;
4. the production cost is high and the product weight is heavy because a large amount of nonferrous metals such as magnetic core materials, enamelled wires and the like are used in production;
2. the ac current divider is shown in fig. 1, and has a structure including copper bars and a manganese copper resistor sheet, and has the following disadvantages:
1. the volume is large: the diverter inputs 6300A and outputs 75mV, the finished product is large in size, and the size of the finished product reaches 150 x 100 x 46 (mm);
2. the accuracy becomes poor: when the current 6300A is output 75mV, the conventional working current is output 7.5mV near 630A, and the transmission line distance is long because the amplitude is too small, and the measurement accuracy is deteriorated due to the interference of a strong electromagnetic field in the transmission process;
3. the signal is directly output, can not be directly sent into the computer protection equipment without isolation treatment, and is changed into the computer protection equipment which can identify weak current or voltage after secondary electric signal amplification and isolation treatment;
4. the power consumption is large, 75mV is output, and 472.5VA is consumed when the conveying current is 6300A;
5. since power is consumed 472.5VA at a current of 6300A, heat generation is high;
6. the line loss is large, in order to collect 75mV, two sampling methods are adopted, 1) sampling is carried out on a copper bar, the voltage of 75mV can be met only on a long copper bar because of the 0.01673 ohm of pure copper, mm < 2 >/m is very small, 2) the length and the volume of a product are reduced by using a manganese-copper sampling voltage, the line loss of the manganese-copper sampling line is increased by 30 times under the condition of the same volume because of the 0.47 ohm of manganese-copper, mm < 2 >/m is relatively large, and the line loss of the manganese-copper sampling line is increased by 30 times;
7. the production of the copper alloy has the advantages that a large amount of red copper, manganese copper and other nonferrous metals are used, so that the cost is high, and the product weight is high; based on the problems of the alternating current transformer and the current shunt, a novel sensor with low power consumption, small volume, high precision, low temperature rise and self-isolation output needs to be developed to solve the existing problems.
Disclosure of Invention
The utility model aims to provide an integrated galvanic isolation electronic sensor, which solves the problems of large power consumption, large volume, low precision, high temperature rise, small output amplitude, large interference and incapability of isolation of the traditional alternating current shunt.
0004. In order to achieve the above purpose, the present utility model provides the following technical solutions: an integrated galvanically isolated electronic sensor, comprising,
a copper bar;
the signal amplifying circuit is used for amplifying a weak voltage signal selected from a preset position of the copper bar under the action of current transmission;
the isolation output circuit is used for receiving the signals sent by the signal amplifying circuit and isolating and outputting the signals;
the power supply voltage stabilizing circuit is used for isolating the power supply voltage and sending the power supply voltage into the signal amplifying circuit;
wherein, the copper bar is the overall structure.
0005. Preferably, the power supply voltage stabilizing circuit includes: a dc-ac converter Z1 converting the power supply voltage into a dc voltage, and a transformer B1 for supplying the dc voltage of the dc-ac converter Z1 to the isolation;
the direct-current voltage is transmitted to the transformer B1 for isolation after being generated by the high-frequency switching power supply module.
0006. Preferably, the signal amplifying circuit includes:
an operational amplifier A2, a resistor R1, a resistor R2, and a resistor R3 connected to the operational amplifier;
the resistor R1 and the resistor R2 are respectively connected with the copper bars.
0007. Preferably, the isolation output circuit includes:
a resistor R4 with one end connected with the signal amplifying circuit and a mutual inductor B2 connected with the other end of the resistor R4.
0008. Preferably, the isolation output circuit further includes: a resistor R5 with one end connected with the signal amplifying circuit and a mutual inductor B3 connected with the other end of the resistor R5;
a resistor R6 with one end connected with the signal amplifying circuit and a mutual inductor B4 connected with the other end of the resistor R6.
0009. Preferably, the copper bar is provided with two signal sampling ends, and the two signal sampling ends are respectively connected with the resistor R1 and the resistor R2 through two acquisition rods.
0010. Preferably, the length of the acquisition rod is 10mm.
0011. Preferably, the copper resistance is calculated according to the following formula: the calculation formula is as follows: r=ρ×l/S, where R is the resistance, ρ is the conductor resistivity, L is the length, and S is the cross-sectional area.
0012. Preferably, the isolation output voltage of the mutual inductor B2, the mutual inductor B3 and the mutual inductor B4 is 1500mV.
0013. The copper bar is also connected with one end of a supporting rod, and the other end of the supporting rod is connected with a shell for packaging the signal amplifying circuit, the power supply voltage stabilizing circuit and the isolation output circuit. The utility model has the technical effects and advantages that: this integrated electric current keeps apart electronic sensor, electric control module installs on the copper bar main part directly, the module fixed point is for gathering the signal input, high efficiency is energy-conserving, reduce temperature, small, save material cost, manufacturing cost, reduce installation space, energy-conserving effect is showing, compare with equal current specification volume shunt product, energy-conserving effect 97.34%, the temperature decline value is greater than 116.8 degrees, the signal is through the direct remote relay protection equipment adoption of sending of isolation processing simultaneously, the output precision reaches the high accuracy of 0.2% level, and have multiple output, provide very big facility for the user.
Drawings
0014. FIG. 1 is a schematic diagram of a conventional AC current divider according to the present utility model;
FIG. 2 is a front view of an integrated galvanically isolated electronic sensor of this utility model;
FIG. 3 is a left side view of the integrated galvanically isolated electronic sensor of this utility model;
FIG. 4 is a schematic view of a copper bar according to the present utility model;
fig. 5 is a circuit diagram of the present utility model.
0015. In the figure: 1. a power supply voltage stabilizing circuit; 2. a signal amplifying circuit; 3. isolating the output circuit; 10. a manganese copper resistor sheet; 11. a housing; 12. a collection rod; 13. a copper bar; 14. a support rod; 15. an output port; 131. a current copper bar wire inlet end; 132. a signal sampling end; 133. and a support hole.
Description of the embodiments
0016. The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.
0017. The present utility model provides an integrated galvanically isolated electronic sensor as shown in fig. 2, 5, comprising,
a copper bar 13;
an amplifying circuit 2 for amplifying the voltage signal collected on the copper bar 13; the signal amplification circuit 2 includes:
an operational amplifier A2, a resistor R1, a resistor R2, and a resistor R3 connected to the operational amplifier;
the resistor R1 and the resistor R2 are connected to the copper bar 13, respectively.
0018. An isolation output circuit 3 for isolating the signal fed from the signal amplifying circuit 2; the isolation output circuit 3 includes:
a resistor R4 with one end connected with the signal amplifying circuit 2 and a mutual inductor B2 connected with the other end of the resistor R4;
a resistor R5 with one end connected with the signal amplifying circuit 2 and a transformer B3 connected with the other end of the resistor R6;
a resistor R6 with one end connected with the signal amplifying circuit 2, and a mutual inductor B4 connected with the other end of the resistor R6.
0019. A power supply voltage stabilizing circuit 1 for isolating the power supply voltage and sending the power supply voltage to the signal amplifying circuit 2; the power supply voltage stabilizing circuit 1 includes: a DC-AC converter for supplying the high-frequency energy voltage generated by the DC voltage to an isolated transformer B1;
the direct-current voltage is transmitted to the transformer B1 for isolation after being generated by the high-frequency energy voltage by the high-frequency switching power supply module, and is not marked in the figure;
wherein, the copper bar 13 is of an integral structure.
0020. In this embodiment, as shown in fig. 3, the signal amplifying circuit 2, the isolation output circuit 3 and the power supply voltage stabilizing circuit 1 are all encapsulated in a casing 11, the casing 11 has a rectangular parallelepiped structure, and at least one output port 15 is disposed on the surface of the casing 11 and connected to the isolation output circuit 3;
as shown in fig. 4, the copper bar 13 is made of rectangular and monolithic copper, and is provided with two current copper wire inlet ends 131, two signal sampling ends 132 and two supporting holes 133 respectively, the two signal sampling ends 132 are connected with the acquisition rod 12, one end of the supporting rod 14 is fixed in the two supporting holes 133, and the other end of the supporting rod 14 is fixed with the shell 11; the length of the acquisition rod 14 ranges: 10mm-15mm; preferably 10mm;
the copper bar 13 is provided with two signal sampling ends 132, and the two signal sampling ends 132 are respectively connected with a resistor R1 and a resistor R2 through two acquisition rods 14;
the copper resistance is calculated according to the following formula: the calculation formula is as follows: r=ρ×l/S, where R is the resistance, ρ is the conductor resistivity, L is the length, and S is the cross-sectional area.
0021. And the isolation output voltage of the mutual inductor B2, the mutual inductor B3 and the mutual inductor B4 is 1500mV.
0022. In this example, the rated current 6300A is 10 times that of the existing ac transformer and ac shunt: the structure of the prior alternating current shunt adopts a three-section design, and a manganese copper resistor disc 10 is arranged in the middle; the integrated current isolation electronic sensor is small in size, can meet the collection requirement of 10 times 6300A current when being used in a 630A current circuit, the current circuit is directly connected by adopting an integral copper bar, when 630A is input, a sampling signal utilizes weak voltage (the resistivity of pure copper is 0.01673 ohm.mm < 2 >/m) generated by alternating current flowing through the copper bar, the sampling voltage is 2 mM, when the current of 10 times 6300A is 10 times, the sampling voltage is 20mV, the product size is small, and the use size is 110 x 40 x 4 (mm);
the isolation output voltage of the integrated current isolation electronic sensor is 1500mV, and the amplitude is large, so that the integrated current isolation electronic sensor is not interfered by strong electromagnetic interference in the transmission process, and the measurement precision is high; meanwhile, the signals are isolated output and can be directly sent to relay protection equipment for use; the multipath signals are isolated and independently output, a plurality of sampling signals can be provided for local and remote equipment, elements repeatedly installed and adopted are omitted, and space and cost are saved for user equipment;
the integrated current isolation electronic sensor consumes less power, and consumes 1.26VA when rated input current 630A and 126VA when 10 times input current 6300A because of sampling voltage of 2 mV; the heat generated by the power consumption of 126VA is low when the current is 6300A;
importantly, in the circuit of 630A, the conventional current divider adopts a product with 6300A specification, and the integrated current isolation electronic sensor only needs to be the same as the 630A current divider in volume, and the red copper is greatly reduced in production, so that the manganese copper is omitted, the production process is simple, the cost is low, and the product weight is light;
energy-saving effect contrast, the integrated galvanic isolation electronic sensor adopts the volume of a 630A class current shunt when in 630A, and compares with a conventional 630A current shunt:
the voltage unit is V, the current unit is A, and the power consumption unit is VA in the following table;
0023. the working principle of the utility model is as follows:
the power supply voltage is input to the direct current-alternating current converter Z1 through a first port 1# and a second port 2# of the power supply voltage stabilizing circuit 1 and is converted into direct current voltage, the direct current voltage is processed by the high-frequency switching power supply module and is sent to the transformer B1 to be isolated to output positive working voltage V1 and negative working voltage V2, the positive working voltage V1 is connected with a fifth port 5# of the operational amplifier A2 through a third port 3# of the power supply voltage stabilizing circuit, the negative working voltage V2 is connected with a fourth port 4# of the operational amplifier A2 through a fifth port 5# of the power supply voltage stabilizing circuit 1, and a GND ground wire end is connected with a public ground through a fourth port 4# of the power supply voltage stabilizing circuit 1; the power supply voltage stabilizing circuit 1, the signal amplifying circuit 2 and the isolation output circuit 3 are all of modularized design, and an input port and an output port are arranged;
the first port 1# of the copper bar A1 is connected with one end of a resistor R1, a weak voltage signal is sent to the input end 1# of an operational amplifier A2, and the second port 2# of the copper bar A1 is connected with a public ground;
the second port 2# of the operational amplifier A2 is connected with the public ground through a resistor R2, one end of a resistor R3 for controlling the output amplitude of the operational amplifier is connected with the input end 1# of the operational amplifier A2, the other end of the resistor R3# is connected with the output end 3# of the operational amplifier A2, and the output end 3# of the operational amplifier A2 is connected with a resistor R4, a resistor R5 and a resistor R6 and sends amplified voltage to an isolation transformer B2, a transformer B3 and a transformer B4;
the output end 3# of the operational amplifier A2 is connected with a resistor R4, a resistor R5 and a resistor R6, the other end of the resistor R4 is connected with 1# of a transformer B2, the second port 2# of the transformer B2 is connected with the public ground, and an isolation output signal is generated and output through the third port 3# and the fourth port 4# of the transformer B2.
0024. This integrated electric current keeps apart electronic sensor, electric control module installs on the copper bar main part directly, the module fixed point is for gathering the signal input, high-efficient energy-conservation, reduce work temperature rise, small, save material cost, manufacturing cost, reduce installation space, energy-conserving effect is showing, compare with equal current specification volume shunt product, energy-conserving effect 97.34%, the temperature decline value is greater than 116.8 degrees, the signal is through the direct remote relay protection equipment adoption of sending of isolation processing simultaneously, output precision 0.2% level precision, and have multiplexed output, provide very big facility for the user.
0025. Finally, it should be noted that: the foregoing description is only illustrative of the preferred embodiments of the present utility model, and although the present utility model has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments described, or equivalents may be substituted for elements thereof, and any modifications, equivalents, improvements or changes may be made without departing from the spirit and principles of the present utility model.
Claims (9)
1. An integrated galvanic isolation electronic sensor, characterized in that: comprising the steps of (a) a step of,
a copper bar;
the signal amplifying circuit is used for amplifying the voltage signals acquired on the copper bars;
the isolation output circuit is used for receiving the signals sent by the signal amplifying circuit and isolating and outputting the signals;
the power supply voltage stabilizing circuit is used for isolating the power supply voltage and sending the power supply voltage into the signal amplifying circuit;
wherein, the copper bar is the overall structure.
2. An integrated galvanically isolated electronic sensor according to claim 1, characterized in that: the power supply voltage stabilizing circuit comprises: a dc-ac converter Z1 converting a power supply voltage into a dc voltage, a transformer B1 for electrical isolation;
the direct-current voltage is transmitted to the transformer B1 for isolation after being generated by the high-frequency switching power supply module.
3. An integrated galvanically isolated electronic sensor according to claim 1, characterized in that: the signal amplifying circuit includes:
an operational amplifier A2, a resistor R1, a resistor R2, and a resistor R3 connected to the operational amplifier;
the resistor R1 and the resistor R2 are respectively connected with the copper bars.
4. An integrated galvanically isolated electronic sensor according to claim 1, characterized in that: the isolated output circuit includes:
a resistor R4 with one end connected with the signal amplifying circuit and a mutual inductor B2 connected with the other end of the resistor R4.
5. An integrated galvanically isolated electronic sensor according to claim 4, characterized in that: the isolated output circuit further includes: a resistor R5 with one end connected with the signal amplifying circuit and a mutual inductor B3 connected with the other end of the resistor R5;
a resistor R6 with one end connected with the signal amplifying circuit and a mutual inductor B4 connected with the other end of the resistor R6.
6. An integrated galvanically isolated electronic sensor according to claim 1, characterized in that: the copper bar is provided with two signal sampling ends, and the two signal sampling ends are respectively connected with the resistor R1 and the resistor R2 through two acquisition rods.
7. An integrated galvanically isolated electronic sensor according to claim 6, characterized by: the length of the acquisition rod is 10mm.
8. An integrated galvanically isolated electronic sensor according to claim 1, characterized in that: the copper bar is also connected with one end of a supporting rod, and the other end of the supporting rod is connected with a shell for packaging the signal amplifying circuit, the power supply voltage stabilizing circuit and the isolation output circuit.
9. An integrated galvanically isolated electronic sensor according to claim 5, characterized in that: and the isolation output voltage of the mutual inductor B2, the mutual inductor B3 and the mutual inductor B4 is 1500mV.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321438661.3U CN220105134U (en) | 2023-06-07 | 2023-06-07 | Integrated galvanic isolation electronic sensor |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321438661.3U CN220105134U (en) | 2023-06-07 | 2023-06-07 | Integrated galvanic isolation electronic sensor |
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| Publication Number | Publication Date |
|---|---|
| CN220105134U true CN220105134U (en) | 2023-11-28 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202321438661.3U Active CN220105134U (en) | 2023-06-07 | 2023-06-07 | Integrated galvanic isolation electronic sensor |
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| CN (1) | CN220105134U (en) |
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2023
- 2023-06-07 CN CN202321438661.3U patent/CN220105134U/en active Active
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