CN110058071A - Zero sequence current sensor circuit topology and switch pole - Google Patents
Zero sequence current sensor circuit topology and switch pole Download PDFInfo
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- CN110058071A CN110058071A CN201910362941.2A CN201910362941A CN110058071A CN 110058071 A CN110058071 A CN 110058071A CN 201910362941 A CN201910362941 A CN 201910362941A CN 110058071 A CN110058071 A CN 110058071A
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- 238000000819 phase cycle Methods 0.000 claims abstract description 78
- 230000005611 electricity Effects 0.000 claims abstract description 18
- 230000007935 neutral effect Effects 0.000 claims abstract description 10
- 238000005070 sampling Methods 0.000 claims description 12
- 238000000465 moulding Methods 0.000 claims description 3
- 239000004020 conductor Substances 0.000 abstract description 5
- 238000002955 isolation Methods 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 238000004080 punching Methods 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R1/00—Details of instruments or arrangements of the types included in groups G01R5/00 - G01R13/00 and G01R31/00
- G01R1/02—General constructional details
- G01R1/04—Housings; Supporting members; Arrangements of terminals
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
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- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
Abstract
The present invention provides a kind of zero sequence current sensor circuit topology and switch poles, comprising: three-phase phase-sequence current sensor, the phase-sequence current and zero-sequence current of each phase of three-phase electricity share the primary current acquisition coil of three-phase phase-sequence current sensor to acquire；Current transformer, one end of the primary side of current transformer acquire coil with primary current by zero sequence output loop and connect, the other end ground connection of the primary side of current transformer, and are connect by phase sequence output loop with the other end that primary current acquires coil；Resistance RI0, in parallel with the secondary side of current transformer.The error for avoiding the introducings such as interference and the leakage field of space magnetic field, greatly reduces the volume of current transformer；Zero sequence output loop and the isolation of phase sequence output loop Current Transformer solve the problems, such as directly the drawbacks of series resistor on the phase sequence current transformer secondary side neutral conductor influences phase sequence precision and zero sequence impedance matching and requires configuration high-power resistance.
Description
Technical field
The present invention relates to electronic circuit technology fields, and in particular, to zero sequence current sensor circuit topology and switch pole
Column.
Background technique
Zero sequence current sensor is a kind of sensor for acquiring the zero-sequence current in distribution network line, Publication No.
The patent of CN108051689A discloses a kind of zero sequence current sensor, circularizes iron core by least two petal type sets of contacts,
One end of the fixed conducting wire of iron core, the other end of conducting wire are fixed by support ring；The petal type contact of zero sequence current sensor mutually it
Between by welding formed one, petal type contact both ends are additionally provided with fixed spring；The quantity of petal type contact is 8；Zero sequence
The circle number ratio of current sensor is 2000:1；Installation is applied to the user side of power grid.
Zero-sequence current, phase are mainly acquired using three-phases punching electromagnetic type zero sequence current mutual inductors such as racetrack, circles at present
Sequence electric current and zero-sequence current have independent coil to be acquired, and the three-phases punching such as racetrack zero sequence current mutual inductor need to be by three
Phase current passes through mutual inductor, since the interference of three-phase space magnetic field and leakage field etc. introduce biggish error.This outer volume is big, especially
For on-pole switch, installation is inconvenient, therefore, using greatly being limited to.
Technical solution used at present mainly include the following types:
Phase sequence zero sequence absolute coil as shown in Figure 1, punching or racetrack zero sequence current mutual inductor, as shown in Figure 2
Phase sequence zero sequence is seperated, three-phase integratedization zero sequence current mutual inductor and phase sequence zero sequence absolute coil as shown in Figure 3, three-phase separate
Body formula zero sequence current sensor.
Shown in Fig. 4 is the method that kind of simple phase sequence zero sequence shares coil, but has several drawbacks very under this method
It is difficult to resolve certainly:
(1) it is used as safety requirements, the secondary side of three-phase phase-sequence current sensor there must be any to be directly grounded, directly in phase
The mode of series resistor is infeasible on the neutral conductor of sequence Current Transformer Secondary side；
(2) resistance value of sample resistance selects more difficult, the too big precision that can directly influence phase sequence, the too small zero sequence of resistance value
Precision is difficult to realize；
(3) saturation coefficient is considered, so the power requirement of sample resistance is larger, therefore sufficiently bulky；
(4) due to meet certain temperature range, therefore it is required that the temperature coefficient of sample resistance is very low, electricity is required in addition
The power of resistance is larger, and the production of resistance is difficult to, and at high price, does not have practicability.
Summary of the invention
For the defects in the prior art, it the object of the present invention is to provide a kind of zero sequence current sensor circuit topology and opens
Close pole.
A kind of zero sequence current sensor circuit topology provided according to the present invention, comprising:
Three-phase phase-sequence current sensor, the phase-sequence current and zero-sequence current of each phase of three-phase electricity share the three-phase phase-sequence electricity
One primary current of flow sensor acquires coil to acquire；
It is adopted by zero sequence output loop and the primary current one end of current transformer, the primary side of the current transformer
Collect coil connection, the other end ground connection of the primary side of the current transformer, and passes through phase sequence output loop and the primary current
Acquire the other end connection of coil；
Resistance RI0, in parallel with the secondary side of the current transformer.
Preferably, the three-phase phase-sequence current sensor includes that three primary currents acquire coil, the phase sequence electricity of each phase
Stream and zero-sequence current share the primary current acquisition coil of the three-phase phase-sequence current sensor to acquire.
Preferably, the zero sequence output end a of three primary current acquisition coils1、b1、c1Being connected, it is defeated to constitute the zero sequence
Circuit out.
Preferably, the phase sequence output end a of three primary current acquisition coilsh、bh、chIt is separately connected positive sequence sampling electricity
Hinder RIa、RIb、RIcOne end, the positive sequence sampling resistor RIa、RIb、RIcThe other end be connected and constitute the phase sequence output loop.
Preferably, further include voltage acquisition device, acquire the resistance RI0The voltage value at both ends.
Preferably, the three-phase electricity uses Y connection.
Preferably, the three-phase phase-sequence current sensor is connected to the neutral point of the Y connection.
A kind of zero sequence current sensor circuit topology provided according to the present invention, comprising:
Three-phase phase-sequence current sensor, the phase-sequence current and zero-sequence current of each phase of three-phase electricity share the three-phase phase-sequence electricity
One primary current of flow sensor acquires coil to acquire；
It is adopted by zero sequence output loop and the primary current one end of current transformer, the primary side of the current transformer
Collect coil connection, the other end ground connection of the primary side of the current transformer, and passes through phase sequence output loop and the primary current
Acquire the other end connection of coil；
Resistance RI0, in parallel with the secondary side of the current transformer；
The three-phase phase-sequence current sensor includes that three primary currents acquire coil, the phase-sequence current and zero sequence of each phase
One primary current of three-phase phase-sequence current sensor described in current sharing acquires coil to acquire；
The zero sequence output end a of three primary current acquisition coils1、b1、c1It is connected and constitutes the zero sequence output loop；
The phase sequence output end a of three primary current acquisition coilsh、bh、chIt is separately connected positive sequence sampling resistor RIa、
RIb、RIcOne end, the positive sequence sampling resistor RIa、RIb、RIcThe other end be connected and constitute the phase sequence output loop；
Further include voltage acquisition device, acquires the resistance RI0The voltage value at both ends；
The three-phase electricity uses Y connection；
The three-phase phase-sequence current sensor is connected to the neutral point of the Y connection.
A kind of switch pole provided according to the present invention, including above-mentioned zero sequence current sensor circuit topology.
Preferably, the zero sequence current sensor circuit topology and the switch pole one cast molding.
Compared with prior art, the present invention have it is following the utility model has the advantages that
1, zero-sequence current is directly acquired using three-phase phase-sequence current sensor, phase-sequence current and zero-sequence current share one one
Primary current acquires coil, avoids the error of the introducings such as interference and the leakage field of space magnetic field, acquisition precision greatly improves, greatly
The volume of current transformer is reduced, it is not only easy to install, but also can directly be poured into switch pole, it is one with switching at melting
Body；
2, zero sequence output loop and phase sequence output loop Current Transformer isolation, solve directly in phase-sequence current it is mutual
Series resistor on the sensor secondary side neutral conductor and while the problem of influence phase sequence precision, also solve zero sequence impedance matching and want
The drawbacks of seeking configuration high-power resistance.
Detailed description of the invention
Upon reading the detailed description of non-limiting embodiments with reference to the following drawings, other feature of the invention,
Objects and advantages will become more apparent upon:
Fig. 1 to Fig. 3 is the structural schematic diagram of three kinds of existing zero sequence current sensors；
Fig. 4 is the structural schematic diagram that phase sequence zero sequence shares coil；
Fig. 5 is structural schematic diagram of the invention.
Specific embodiment
The present invention is described in detail combined with specific embodiments below.Following embodiment will be helpful to the technology of this field
Personnel further understand the present invention, but the invention is not limited in any way.It should be pointed out that the ordinary skill of this field
For personnel, without departing from the inventive concept of the premise, several changes and improvements can also be made.These belong to the present invention
Protection scope.
As shown in figure 5, according to a kind of zero sequence current sensor circuit topology provided in this embodiment, comprising:
Three-phase phase-sequence current sensor, the phase-sequence current and zero-sequence current of each phase of three-phase electricity share three-phase phase-sequence electric current and pass
One primary current of sensor acquires coil to acquire；
Current transformer, one end of the primary side of current transformer acquire coil by zero sequence output loop and primary current and connect
It connects, the other end ground connection of the primary side of current transformer, and acquires the other end of coil by phase sequence output loop and primary current
Connection；
Resistance RI0, in parallel with the secondary side of current transformer.
Wherein, A, B, C are respectively the primary current acquisition coil of three-phase phase-sequence electric current, and primary current is converted to two respectively
Primary current ia,ib,ic, RIa,RIb,RIcFor the positive sequence sampling resistor of phase sequence, secondary current is converted into voltage as phase sequence respectively
Electric current；Respectively by A, a of tri- current acquisition coils of B, C1、b1、c1Be connected the zero-sequence current i generated01Access current transformer
CT0 primary side one end, then ah, bh, ch of ABC are concatenated to the connected access CT0 primary side of output end after positive sequence sampling resistor respectively
The other end induces electric current i in the secondary coil of CT002, a resistance R is incorporated on the secondary coil of CT0I0, in RI0Upper acquisition
The voltage U arrivedI0That is the corresponding voltage value of zero-sequence current.
Specifically, three-phase phase-sequence current sensor includes that three primary currents acquire coils, the phase-sequence current of each phase and
Zero-sequence current shares the primary current acquisition coil of three-phase phase-sequence current sensor to acquire.Three primary current gathering lines
The zero sequence output end a of circle1、b1、c1It is connected and constitutes zero sequence output loop.The phase sequence output end a of three primary current acquisition coilsh、
bh、chIt is separately connected positive sequence sampling resistor RIa、RIb、RIcOne end, positive sequence sampling resistor RIa、RIb、RIcThe other end be connected constitute
Phase sequence output loop.
Three-phase electricity uses Y connection, seals in three-phase phase-sequence current sensor using the neutral point of Y connection, directly acquires
Zero-sequence current, phase-sequence current and zero-sequence current share a primary current and acquire coil, avoid the interference and leakage of space magnetic field
The error of the introducings such as magnetic, acquisition precision greatly improve, and greatly reduce the volume of current transformer.
Zero sequence output loop and the isolation of phase sequence output loop Current Transformer, are solving directly in phase-sequence current mutual inductance
Series resistor on the device secondary side neutral conductor and while the problem of influence phase sequence precision, also solve zero sequence impedance matching and require
The drawbacks of configuring high-power resistance is (if directly series resistor acquires zero-sequence current on the phase sequence neutral conductor, it is required that high-power
The problems such as resistance increases the load of phase sequence sensor, added losses is caused to generate heat).
The present invention also provides a kind of switch poles, using above-mentioned zero sequence current sensor circuit topology.The zero sequence electricity
Flow sensor circuit topology and the switch pole one cast molding.
In the description of the present application, it is to be understood that term " on ", "front", "rear", "left", "right", " is erected at "lower"
Directly ", the orientation or positional relationship of the instructions such as "horizontal", "top", "bottom", "inner", "outside" is orientation based on the figure or position
Relationship is set, description the application is merely for convenience of and simplifies description, rather than the device or element of indication or suggestion meaning are necessary
It with specific orientation, is constructed and operated in a specific orientation, therefore should not be understood as the limitation to the application.
Specific embodiments of the present invention are described above.It is to be appreciated that the invention is not limited to above-mentioned
Particular implementation, those skilled in the art can make a variety of changes or modify within the scope of the claims, this not shadow
Ring substantive content of the invention.In the absence of conflict, the feature in embodiments herein and embodiment can any phase
Mutually combination.
Claims (10)
1. a kind of zero sequence current sensor circuit topology characterized by comprising
Three-phase phase-sequence current sensor, each phase phase-sequence current of three-phase electricity and zero-sequence current share the three-phase phase-sequence current sense
One primary current of device acquires coil to acquire；
One end of current transformer, the primary side of the current transformer passes through zero sequence output loop and the primary current gathering line
Circle connection, the other end ground connection of the primary side of the current transformer, and acquired by phase sequence output loop and the primary current
The other end of coil connects；
Resistance RI0, in parallel with the secondary side of the current transformer.
2. zero sequence current sensor circuit topology according to claim 1, which is characterized in that the three-phase phase-sequence electric current passes
Sensor includes that three primary currents acquire coil, and the phase-sequence current and zero-sequence current of each phase share the three-phase phase-sequence electric current and pass
One primary current of sensor acquires coil to acquire.
3. zero sequence current sensor circuit topology according to claim 2, which is characterized in that three primary currents are adopted
Collect the zero sequence output end a of coil1、b1、c1It is connected and constitutes the zero sequence output loop.
4. zero sequence current sensor circuit topology according to claim 2, which is characterized in that three primary currents are adopted
Collect the phase sequence output end a of coilh、bh、chIt is separately connected positive sequence sampling resistor RIa、RIb、RIcOne end, the positive sequence sampling resistor
RIa、RIb、RIcThe other end be connected and constitute the phase sequence output loop.
5. zero sequence current sensor circuit topology according to claim 1, which is characterized in that further include voltage collector
Part acquires the resistance RI0The voltage value at both ends.
6. zero sequence current sensor circuit topology according to claim 1, which is characterized in that the three-phase electricity uses Y shape
Wiring.
7. zero sequence current sensor circuit topology according to claim 6, which is characterized in that the three-phase phase-sequence electric current passes
Sensor is connected to the neutral point of the Y connection.
8. a kind of zero sequence current sensor circuit topology characterized by comprising
Three-phase phase-sequence current sensor, the phase-sequence current and zero-sequence current of each phase of three-phase electricity share the three-phase phase-sequence electric current and pass
One primary current of sensor acquires coil to acquire；
One end of current transformer, the primary side of the current transformer passes through zero sequence output loop and the primary current gathering line
Circle connection, the other end ground connection of the primary side of the current transformer, and acquired by phase sequence output loop and the primary current
The other end of coil connects；
Resistance RI0, in parallel with the secondary side of the current transformer；
The three-phase phase-sequence current sensor includes that three primary currents acquire coil, zero-sequence current, the phase-sequence current of each phase
The primary current acquisition coil of the three-phase phase-sequence current sensor is shared with zero-sequence current to acquire；
The zero sequence output end a of three primary current acquisition coils1、b1、c1It is connected and constitutes the zero sequence output loop；
The phase sequence output end a of three primary current acquisition coilsh、bh、chIt is separately connected positive sequence sampling resistor RIa、RIb、RIc
One end, the positive sequence sampling resistor RIa、RIb、RIcThe other end be connected and constitute the phase sequence output loop；
Further include voltage acquisition device, acquires the resistance RI0The voltage value at both ends；
The three-phase electricity uses Y connection；
The three-phase phase-sequence current sensor is connected to the neutral point of the Y connection.
9. a kind of switch pole, which is characterized in that including the electricity of zero sequence current sensor described in claim 1 to 7 any one
Road topology.
10. switch pole according to claim 9, which is characterized in that the zero sequence current sensor circuit topology and institute
State switch pole one cast molding.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201910362941.2A CN110058071A (en) | 2019-04-30 | 2019-04-30 | Zero sequence current sensor circuit topology and switch pole |
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| CN201910362941.2A CN110058071A (en) | 2019-04-30 | 2019-04-30 | Zero sequence current sensor circuit topology and switch pole |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111856112A (en) * | 2020-06-18 | 2020-10-30 | 上海置信智能电气有限公司 | High-precision zero-sequence current sensor based on current synthesis and precise magnetomotive transformation |
| CN116148521A (en) * | 2023-04-14 | 2023-05-23 | 烟台东方威思顿电气有限公司 | High-voltage metering device and depth fusion type polar column |
| CN116500328A (en) * | 2023-06-06 | 2023-07-28 | 无锡市锡山湖光电器有限公司 | High-precision three-phase current sensor |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111856112A (en) * | 2020-06-18 | 2020-10-30 | 上海置信智能电气有限公司 | High-precision zero-sequence current sensor based on current synthesis and precise magnetomotive transformation |
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| CN116500328A (en) * | 2023-06-06 | 2023-07-28 | 无锡市锡山湖光电器有限公司 | High-precision three-phase current sensor |
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