CN206312746U - Current transformer - Google Patents
Current transformer Download PDFInfo
- Publication number
- CN206312746U CN206312746U CN201621295107.4U CN201621295107U CN206312746U CN 206312746 U CN206312746 U CN 206312746U CN 201621295107 U CN201621295107 U CN 201621295107U CN 206312746 U CN206312746 U CN 206312746U
- Authority
- CN
- China
- Prior art keywords
- shaped yoke
- sensing head
- current transformer
- current
- shaped
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn - After Issue
Links
Abstract
The utility model is related to a kind of current transformer.Purpose is to provide a kind of current transformer, both the characteristic of low cost with manganese copper diverter, and is separated with voltage circuit with the current loop that transformer is similar to, and is conducive to being greatly reduced the volume and weight of three-phase intelligent ammeter, reduces cost.Scheme：Current transformer, it includes sensing head, flow guide bar and C-shaped yoke, wherein, sensing head, its output end connection current sampling circuit；Flow guide bar, through C-shaped yoke, its two ends connects live wire end of incoming cables and live wire leading-out terminal respectively, for producing alternating magnetic field near openend side in C-shaped yoke after energization；C-shaped yoke, the sensing head is inserted by the openend of C-shaped yoke, makes C-shaped yoke that the sensing head is completely covered, and the alternating magnetic field induces electromotive force in the sensing head output end.The utility model is mainly used in the current measurement of intelligent electric meter industry.
Description
Technical field
The utility model is related to a kind of current transformer, is mainly used in the current measurement of intelligent electric meter industry.
Background technology
At present, the current measurement circuit of intelligent electric energy meter industry, generally uses manganese copper diverter and electromagnetic type Current Mutual Inductance
Device.
Copper-manganese current divider type current sensor is with low cost, and its operation principle is electric resistance partial pressure, because the resistance of copper-manganese is with temperature
The change of degree is smaller, but discreteness is than larger, therefore, it is generally used in 2.0 grades of single-phase electric energy meter.To common 220V 5
(60) electric energy meter of A, its sample resistance resistance is about between 250~500 μ Ω, caloric value about 1~2W.
The advantage of manganese copper diverter is：Processing it is simple, with low cost, DC component and higher hamonic wave can be measured.Frequently
Rate characteristic can stablize transmission and (be limited by ammeter measurement loop sample rate, actually used scope generally exists from DC-1MHz signals
Below 25kHz).
The shortcoming of manganese copper diverter is：1st, resistance heating amount is big during high current, if screw crimping is loosely when terminal is assembled
Gu, or radiating treatment is improper, it is easy to burn out ammeter.2nd, due to metal ingredient and processing reason, cause resistance discrete
Property is larger, and although resistance varies with temperature small, but is brokenly changed by temperature, therefore, be not suitable for high-precision measuring.
Because voltage and current signal common port cannot be separated (see Fig. 1), it is impossible to directly by single-phase three-wire, the line of two-phase two,
Two-phase, three-wire, phase three-wire three, three-phase and four-line etc. are needed in the applied environment of multichannel electric current sampling and measuring.
It will be seen from figure 1 that using the electric energy meter of manganese copper diverter, live wire L be as measurement loop reference " " make
(it is general in below 5V that computation chip is pressure-resistant, if voltage input is used into live wire L, and using zero line N as ground wire,
Then the pressure difference of two simulation inputs of computation chip is up to 220VAC, and chip holds be can't stand), manganese copper diverter is " hard with live wire
Connection ".
Current transformer is according to electromagnetic induction principle.As shown in Fig. 2 current transformer be by close iron core and around
Group composition, seldom, string is in the circuit of electric current of measurement is needed, therefore it often has the whole of circuit for its first winding number of turn
Electric current flows through, and Secondary Winding turn ratio is more, is serially connected in measuring instrumentss and protective loop, current transformer operationally, it
Secondary circuit all the time be closure, therefore measuring instrumentss and protective loop series coil impedance very little, current transformer
The close short circuit of working condition.The advantage of transformer is the good linearity, and stability is high, the degree of accuracy little with temperature change, especially
It is adapted to the measurement of degree of precision (0.5S grades).
Reference edge using the current sampling of the electric energy meter of current transformer is connected in secondary side with zero line, therefore primary side
It is to isolate (see Fig. 3) with voltage circuit that electric current input is, therefore, the reference edge of computation chip can be zero line N, so measure
The voltage difference of multiple analog input ends of chip will be controlled in below 2V, in the permission model of common below the 5V operating voltages of chip
In enclosing.Voltage and the cut-in method being galvanically isolated, are particularly suitable for the application scenario of requirement two or more current loop measurement, such as two
Phase table, phase three-wire three table and three-phase and four-line table etc..
The shortcoming of transformer is：Volume is big, high cost, anti-overload ability are weak, and the frequency range of measurable signal is general not
Can not be opened a way more than 2.5kHz, especially secondary side current measuring loop, can otherwise produce high voltage and damage measurement electricity
Road！
The content of the invention
The purpose of this utility model is to overcome above-mentioned problem, there is provided a kind of current transformer, both with copper-manganese
The characteristic of low cost of current divider, and separated with voltage circuit with the current loop that transformer is similar to, be conducive to significantly subtracting
The volume and weight of light three-phase intelligent ammeter, reduces cost.
The purpose of this utility model is completed by following technical solution,
Current transformer, it includes sensing head, flow guide bar and C-shaped yoke, wherein,
Sensing head, its output end connection current sampling circuit；
Flow guide bar, through C-shaped yoke, its two ends connects live wire end of incoming cables and live wire leading-out terminal respectively, for after energization in C
Shape yoke produces alternating magnetic field near openend side；
C-shaped yoke, the sensing head is inserted by the openend of C-shaped yoke, makes C-shaped yoke that the sensing is completely covered
Head, the alternating magnetic field induces electromotive force in the sensing head output end.
It is inserted with the openend of the C-shaped yoke and inserts C with its opening direction identical C-shaped insulating trip, the sensing head
The openend of shape insulating trip, makes C-shaped yoke and C-shaped insulating trip that the sensing head is completely covered；The flow guide bar from C-shaped yoke and
C-shaped insulating trip encloses in cavity and passes through.
The sensing head is an air core solenoid formed using wire uniform winding, air core solenoid two ends connection institute
State current sampling circuit.
The internal diameter of the air core solenoid is 0.5-1.5mm, and the winding number of turn is 1-10 circles.
The air core solenoid current sampling circuit is fixed on embedded mode where pcb board on.
The sensing head is that the planar spiral-type or plane directly printed on the pcb board where the current sampling circuit are more
The spiral PCB types air core coil of side shape.
The PCB types air core coil number of turn is 3 circles, internal diameter 0.5-2mm, external diameter 4.5mm.
The flow guide bar includes that order is connected to form the end of incoming cables linkage section of U-shaped, sensing section, leading-out terminal linkage section；Wherein
End of incoming cables linkage section connection live wire end of incoming cables, leading-out terminal linkage section connection live wire leading-out terminal, sensing section passes through the C-shaped yoke,
So that the C-shaped yoke at least covering part sensing section, forms the arrangement states that flow guide bar mutually hooks drawing with C-shaped yoke.
The C-shaped yoke is made of permalloy, microcrystallizing alloy or silicon steel sheet.
The C-shaped yoke is made into integration using permalloy, or is formed by stacking using microcrystallizing alloy or permalloy, or
Person is formed by stacking using silicon steel sheet.
The utility model has the following advantages and effect compared with prior art：
1st, the utility model replaces unshakable in one's determination and winding using the more simple compact sensing head of structure, reduces noble metal material
Expect the consumption of (copper), alleviate weight, reduce volume.2nd, voltage and current loop in polyphase ac electrical measurement are easily achieved
Primary side electrical separation, simplify the Power Management Design of sample circuit.3rd, sensing head is fixed on the pcb board with embedded mode
(air core solenoid), or directly print in (planar spiral-type or plane polygon helical winding) on the pcb board so that
Transformer can be built in inside electric energy meter in the case where very little inner space is only taken up, so as to greatly reduce the whole of electric energy meter
Body volume.4th, because without iron core, the utility model significantly improves without hysteresis effect and magnetic saturation phenomenon, bandwidth.5th, pass
It is minimum on tested loop influence without electrical connection between sense head and tested electric current.6th, dynamic range is wider, can solve the problem that electrically
Change the electric energy metrical problem of the impact loads such as railway, large-scale electromagnetic oven.7th, low cost.
Brief description of the drawings
Fig. 1 is the ammeter measurement loop schematic diagram using manganese copper diverter in the utility model background technology.
Fig. 2 is the structure chart of current transformer in the utility model background technology.
Fig. 3 is the ammeter measurement loop schematic diagram using current transformer in the utility model background technology.
Fig. 4 is the schematic diagram of sensing head in embodiment 1.
Fig. 5 is that Fig. 4 sensing heads embed the structural representation being fixed on pcb board.
Fig. 6 is the front view of the transformer of embodiment 1.
Fig. 7-1 is the structure chart of monoblock type permalloy C-shaped yoke.
Fig. 7-2 is the structure chart of superposed type permalloy or microcrystallizing alloy C-shaped yoke.
Fig. 7-3 is the structure chart of superposed type silicon steel sheet C-shaped yoke.
Fig. 8 is using the ammeter measurement loop schematic diagram of the utility model transformer.
Fig. 9 is that embodiment 1 is applied to three structural representations of current loop measurement.
Figure 10 is the explosive view of Fig. 9.
Figure 11 is the schematic diagram of sensing head in embodiment 2.
Figure 12 is the schematic diagram of sensing head in embodiment 3.
Figure 13 is the schematic diagram of sensing head in embodiment 4.
Figure 14 is the schematic diagram of sensing head in embodiment 5.
Specific embodiment
Detailed introduction is done to the utility model below in conjunction with accompanying drawing.
Embodiment 1：
As shown in Fig. 6, Fig. 8, the present embodiment current transformer includes sensing head 1, flow guide bar 2 and C-shaped yoke 3, wherein,
Sensing head 1, as shown in figure 4, being an air core solenoid formed using wire uniform winding, its output end connection electricity
Stream sample circuit；
Flow guide bar 2, including order connected end of incoming cables linkage section 2-1, sensing section 2-2, leading-out terminal linkage section 2-3；Wherein
End of incoming cables linkage section 2-1 connection live wires end of incoming cables, leading-out terminal linkage section 2-3 connection live wire leading-out terminals, sensing section 2-2 is described in
C-shaped yoke 3 simultaneously correspondence be arranged in the side of sensing head 1, for after energization between two planes up and down of the openend of C-shaped yoke 3,
Produce and the linear alternating magnetic field of current strength；
C-shaped yoke 3, the sensing head 1 is inserted by the openend of C-shaped yoke 3, makes C-shaped yoke 3 that the biography is completely covered
Sense first 1, electromotive force is induced (specifically, being produced after flow guide bar is powered using the alternating magnetic field in the output end of the sensing head 1
The magnetic field of change, so as to induce a voltage signal proportional to electric current no-load voltage ratio in sensing head
Its induction coefficient M and coil factor kcoilWith magnet ring magnetic capacity kMagProduct it is related, be expressed as M=kcoil*kMag).This example
In, line (the most short company between two planes up and down of C-shaped yoke openend between 3 two ends (openend) of C-shaped yoke
Line) with the diameter parallel of air core solenoid, on the one hand the constraint leakage field of sensing head 1 on the other hand prevent external magnetic field to external diffusion
Interference to measuring loop, improves certainty of measurement；In order to external magnetic field interference is reduced into bottom line, C-shaped yoke 3 is covered in biography
Resulting structure size in sense first 1 must reach more than 10mmx10mm.
In order to ensure realizing being separated between voltage and circuit measuring loop, the present embodiment is in the opening of the C-shaped yoke 3
It is inserted with end and inserts the openend of C-shaped insulating trip 4, make C-shaped with its opening direction identical C-shaped insulating trip 4, the sensing head 1
Yoke 3 and C-shaped insulating trip 4 are completely covered the sensing head 1；The flow guide bar 2 encloses sky from C-shaped yoke 3 and C-shaped insulating trip 4
Passed through in chamber (being located at the bottom of C-channel).
Preferably, the solenoid current sampling circuit is fixed on embedded mode where pcb board 5 on；Such as
Shown in Fig. 5, specifically, opening up a groove on pcb board 5, solenoid is positioned in the groove, two output end is welded in
On pcb board 5, and it is connected with the current sampling circuit on pcb board.
The solenoidal internal diameter is 0.5-1.5mm, corresponds to direct access (such as respectively：Ib=5A~10A, maximum electricity
Stream input 60A~200A) or be input into (such as through transformer：Rated current In=1A, maximum measurement electric current 2A~6A) etc. it is different should
Use demand；The winding number of turn is 1-10 circles, depending on the thickness (thickness of the solenoidal height less than or equal to pcb board) of pcb board 5 and survey
Depending on the signal input scope at amount end.
In order to solve the Insulation Problems between flow guide bar 2 and air core solenoid, air core solenoid should use enamel-covered wire coiling,
And the wire on pcb board 5 needs lid insulation green oil.
Preferably, the end of incoming cables linkage section 2-1, sensing section 2-2, leading-out terminal linkage section 2-3 are linked in sequence into U-shaped,
Wherein sensing section 2-2 passes through the C-shaped yoke 3 so that the C-shaped yoke 3 at least covering part sensing section 2-2, forms water conservancy diversion
Bar 2 mutually hooks the arrangement states drawn with C-shaped yoke 3.
The material of the c-type yoke 3 can be according to the difference of measuring accuracy, selection permalloy, microcrystallizing alloy, or
Silicon steel sheet etc..Three kinds of C-shaped yokes of structure type are provided in the present embodiment, a kind of by monoblock type permalloy is made, such as Fig. 7-1
Shown, it is adaptable to high current direct measurement of the electric current between 5-200A, advantage is that measurement electric current is big, is difficult saturation, but linearly
Degree deficiency is, it is necessary to carry out segmented compensation；One kind is that permalloy or microcrystallizing alloy congruent manner (10 layers) are made, such as Fig. 7-2 institutes
Show, it is adaptable to low current (0.3-10A) measurement of more than 0.5S high accuracies requirement, the survey of the advantage of permalloy material laminate
Amount wide ranges, have the disadvantage that the linearity needs compensation, and the advantage of microcrystallizing alloy lamination is that the measurement linearity is high, but range ability
It is slightly narrow, it is adapted to 0.2S grades of high-acruracy survey application scenario；One kind is box-like (10 layers) for silicon steel sheet stack, as shown in Fig. 7-3, it is adaptable to
Low current (1-10A) measurement of 1.0 grades of medium error requirements, cost is relatively low.
As shown in Figure 9, Figure 10, the present embodiment is applied to be arranged side by side, it is necessary to set three when three current loops are measured
C-shaped yoke 3 and a C-shaped insulating trip 4, each C-shaped yoke 3 is correspondingly arranged a flow guide bar 2, and C-shaped insulating trip 4 is inserted simultaneously
Three openends of C-shaped yoke 3.
The present embodiment is converted by the way of voltage and current synchronization A/D samplings according to the practical frequency of voltage signal
Cycle, as the integration period of air core solenoid, then carries out digital integration by MCU or DSP.
Embodiment 2：
As shown in figure 11, the present embodiment is substantially the same manner as Example 1, and difference is：The sensing head 1 for directly print in
The spiral PCB types air core coil of plane quadrilateral on pcb board 5 where the current sampling circuit, its number of turn is 3 circles, internal diameter
Din is 2mm, and outside diameter d out is 4.5mm.
Embodiment 3：
As shown in figure 12, the present embodiment is substantially the same manner as Example 1, and difference is：The sensing head 1 for directly print in
The spiral PCB types air core coil of plane hexagon on pcb board 5 where the current sampling circuit, its number of turn is 3 circles, internal diameter
Din is 2mm, and outside diameter d out is 4.5mm.
Embodiment 4：
As shown in figure 13, the present embodiment is substantially the same manner as Example 1, and difference is：The sensing head 1 for directly print in
The spiral PCB types air core coil of planar octagonal on pcb board 5 where the current sampling circuit, its number of turn is 3 circles, internal diameter
Din is 2mm, and outside diameter d out is 4.5mm.
Embodiment 5：
As shown in figure 14, the present embodiment is substantially the same manner as Example 1, and difference is：The sensing head 1 for directly print in
Planar spiral-type PCB type air core coils on pcb board 5 where the current sampling circuit, its number of turn is 3 circles, and internal diameter din is
2mm, outside diameter d out are 4.5mm.
Embodiment 6：
The present embodiment is substantially the same manner as Example 2, and difference is：The internal diameter din of the sensing head 1 is 1.5mm, outside diameter d out
It is 4.5mm.
Embodiment 7：
The present embodiment is substantially the same manner as Example 3, and difference is：The internal diameter din of the sensing head 1 is 1mm, and outside diameter d out is
4.5mm。
Embodiment 8：
The present embodiment is substantially the same manner as Example 4, and difference is：The internal diameter din of the sensing head 1 is 0.6mm, outside diameter d out
It is 4.5mm.
Embodiment 9：
The present embodiment is substantially the same manner as Example 5, and difference is：The internal diameter din of the sensing head 1 is 1.5mm, outside diameter d out
It is 4.5mm.
Claims (10)
1. a kind of current transformer, it is characterised in that：It includes sensing head (1), flow guide bar (2) and C-shaped yoke (3), wherein,
Sensing head (1), its output end connection current sampling circuit；
Flow guide bar (2), through C-shaped yoke (3), its two ends connects live wire end of incoming cables and live wire leading-out terminal respectively, after energization
In C-shaped yoke (3) alternating magnetic field is produced near openend side；
C-shaped yoke (3), the sensing head (1) is inserted by the openend of C-shaped yoke (3), makes C-shaped yoke (3) that institute is completely covered
Sensing head (1) is stated, the alternating magnetic field induces electromotive force in the sensing head (1) output end.
2. current transformer according to claim 1, it is characterised in that：Be inserted with the openend of the C-shaped yoke (3) with
Its opening direction identical C-shaped insulating trip (4), the openend of the sensing head (1) insertion C-shaped insulating trip (4), makes C-shaped yoke
And C-shaped insulating trip (4) is completely covered the sensing head (1) (3)；The flow guide bar (2) is from C-shaped yoke (3) and C-shaped insulating trip
(4) enclose in cavity and pass through.
3. current transformer according to claim 1 and 2, it is characterised in that：The sensing head (1) is equal using wire for one
The even air core solenoid being wound, the air core solenoid two ends connect the current sampling circuit.
4. current transformer according to claim 3, it is characterised in that：The internal diameter of the air core solenoid is 0.5-
1.5mm, the winding number of turn is 1-10 circles.
5. current transformer according to claim 3, it is characterised in that：The air core solenoid is fixed on embedded mode
On pcb board where the current sampling circuit.
6. current transformer according to claim 1 and 2, it is characterised in that：The sensing head (1) is to directly print in institute
State the planar spiral-type or the spiral PCB types air core coil of plane polygon on pcb board where current sampling circuit.
7. current transformer according to claim 6, it is characterised in that：The PCB types air core coil number of turn is 3 circles, interior
Footpath 0.5-2mm, external diameter 4.5mm.
8. current transformer according to claim 1 and 2, it is characterised in that：The flow guide bar (2) includes the connected shape of order
End of incoming cables linkage section (2-1), sensing section (2-2) into U-shaped, leading-out terminal linkage section (2-3)；Wherein end of incoming cables linkage section (2-1)
Connection live wire end of incoming cables, leading-out terminal linkage section (2-3) connection live wire leading-out terminal, sensing section (2-2) passes through the C-shaped yoke (3),
So that the C-shaped yoke (3) at least covering part senses section (2-2), form flow guide bar (2) and mutually hook what is drawn with C-shaped yoke (3)
Arrangement states.
9. current transformer according to claim 1 and 2, it is characterised in that：C-shaped yoke (3) the use permalloy,
Microcrystallizing alloy or silicon steel sheet are made.
10. current transformer according to claim 9, it is characterised in that：The C-shaped yoke (3) uses permalloy one
System using microcrystallizing alloy or permalloy into or being formed by stacking, or be formed by stacking using silicon steel sheet.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621295107.4U CN206312746U (en) | 2016-11-29 | 2016-11-29 | Current transformer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621295107.4U CN206312746U (en) | 2016-11-29 | 2016-11-29 | Current transformer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN206312746U true CN206312746U (en) | 2017-07-07 |
Family
ID=59250892
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201621295107.4U Withdrawn - After Issue CN206312746U (en) | 2016-11-29 | 2016-11-29 | Current transformer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN206312746U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106653339A (en) * | 2016-11-29 | 2017-05-10 | 杭州海兴电力科技股份有限公司 | Current transformer |
-
2016
- 2016-11-29 CN CN201621295107.4U patent/CN206312746U/en not_active Withdrawn - After Issue
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106653339A (en) * | 2016-11-29 | 2017-05-10 | 杭州海兴电力科技股份有限公司 | Current transformer |
| WO2018099153A1 (en) * | 2016-11-29 | 2018-06-07 | 杭州海兴电力科技股份有限公司 | Current transformer |
| CN106653339B (en) * | 2016-11-29 | 2019-08-02 | 杭州海兴电力科技股份有限公司 | Current transformer |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4874493B2 (en) | Magnetic control current or voltage regulator and transformer | |
| CN102360857B (en) | Integrated network distributing transformer with error compensating mutual inductor | |
| CN101206951B (en) | Energy-saving current transformer | |
| CN106291123B (en) | A kind of method directly measuring magnetic cell winding loss | |
| CN106653339B (en) | Current transformer | |
| CN103592490A (en) | High-accuracy electronic compensated current transformer | |
| CN1967266A (en) | Spiral type hollow coil current-sensing device | |
| CN206312746U (en) | Current transformer | |
| CN208399579U (en) | A kind of novel 10kV/35kV Current Voltage sensor | |
| CN202189670U (en) | Combined current converter | |
| AU2017393086B2 (en) | Harmonics filters using semi non-magnetic bobbins | |
| CN1967264B (en) | Spiral hollow coil current transformer with compensating coils | |
| CN203606413U (en) | High-accuracy electronic compensation type current transformer | |
| CN206450738U (en) | Current transformer sensing head and current transformer | |
| CN202351323U (en) | Electric power digital meter adopting Rogowski coil current transformer | |
| CN208400695U (en) | A kind of Multiple coil current transformer of same magnetic circuit | |
| CN207798899U (en) | A kind of current sensor and monitoring system | |
| CN201036148Y (en) | Helix tube type aircore coil current sensor | |
| CN106841808B (en) | The auxiliary winding measurement method of intermediate-frequency transformer winding AC resistance | |
| CN1020520C (en) | High permeance current transformer | |
| CN212568917U (en) | Electronic current sensor for electric energy meter | |
| CN204666709U (en) | Half magnetic core current sensor | |
| CN108666118A (en) | A kind of Multiple coil current transformer of same magnetic circuit and preparation method thereof | |
| CN108414798A (en) | A kind of current sensor, monitoring system and monitoring method | |
| CN201364356Y (en) | Cascade current sensor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20170707 Effective date of abandoning: 20190802 |