CN105301532B - A kind of current transformer hysteresis loop observation procedure - Google Patents
A kind of current transformer hysteresis loop observation procedure Download PDFInfo
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- CN105301532B CN105301532B CN201510769400.3A CN201510769400A CN105301532B CN 105301532 B CN105301532 B CN 105301532B CN 201510769400 A CN201510769400 A CN 201510769400A CN 105301532 B CN105301532 B CN 105301532B
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Abstract
The present invention relates to a kind of current transformer hysteresis loop observation procedures, the magnetic hysteresis information for including by using current transformer primary current and secondary current obtains hysteresis loop, realization current transformer hysteresis loop that can be fast and convenient is observed, the limit hysteresis loop that can easily observe under CT saturation can also easily observe the hysteresis loop under current transformer unsaturation, be particularly suitable for being observed the frequency characteristic of current transformer core.
Description
Technical field
The present invention relates to a kind of current transformer hysteresis loop observation procedures.
Background technology
Current transformer is the current transformation equipment being made of iron cores such as silicon steel sheets, in the power system extensive use.By
In current transformer core, there are hysteresis, and on the design of current transformer, manufacture and operation, there are prodigious influences.Accurately
The hysteresis loop for measuring iron core is current transformer design, the important evidence of manufacture and operation.
Traditional hysteresis loop observation mainly has Hall process and RC oscilloscope methods, as follows
(1) Hall process is the size that the magnetic induction density B in iron core air gap is directly observed using Tesla meter.Hall process is such as
Shown in Fig. 1, electric current I is passed through in Exciting Windings for Transverse Differential Protection, then the intensity of magnetization is,
Wherein, L is ferromagnetic magnetic conduction length, N1For umber of turn on iron core.Hall probe is placed in iron core sample air gap
In, it is consistent with tested core interior average magnetic induction intensity in air gap uniform magnetic field region intrinsic inductance.And H is corresponding with B
Relationship is to constitute the hysteresis loop and magnetization curve of the ferromagnetic material.In addition it also needs to move back iron core before experiment
Magnetic.
Hall process can directly measure the size of iron core intrinsic inductance B, but with this method for closed iron core
It is not appropriate for.
(2) RC oscilloscope methods observe hysteresis loop as shown in Fig. 2, the parameter in figure is only for the purpose of illustration.
In winding N1In pass through magnetizing current i1When, this electric current generates magnetic field in style, is had according to Ampere circuit law：
HL=N1i1-N2i2
Due to N2i2Therefore very little is ignored, by measuring resistance R1On both ends voltage U1, H can be expressed as：
For i2Virtual value, as 10 × 1/ ω c≤R2, i2Can be approximately：
The voltage u at the both ends capacitance ccIt is represented by：
Therefore B can be indicated by capacitance both end voltage.
Show that H, Y-axis show that B can intuitively show iron core hysteresis loop phenomenon with the X-axis of oscillograph.RC oscillographs
Method has simple and convenient, the clear advantage of physical significance.Due to having ignored N2i2When therefore can not be applied to current transformer operation
Hysteresis loop inlet wire is observed, it is suitable that secondary resistance needs to select with capacitance, otherwise will appear wave distortion phenomenon, to observation
Hysteresis loop of the current transformer under different frequency response is also inconvenient.
Both methods is required for independent observation circuit, and is only suitable for the hysteresis loop of a little sample progress iron core
Observation.After current transformer has been manufactured, the hysteresis loop that iron core is observed with above method is very inconvenient.
Invention content
The purpose of the present invention is to provide a kind of current transformer hysteresis loop observation procedures, are deposited in the prior art with overcoming
Defect.
To achieve the above object, the technical scheme is that：A kind of current transformer hysteresis loop observation procedure, according to
Following steps are realized：
Step S1：The primary current of primary side is directly acquired using digital oscilloscope current probe；Shown using the number
After wave device voltage probe measures secondary resistive voltage, it is then converted to secondary current；
Step S2：The primary current acquired, the secondary current and time are subjected to data by Matlab
Processing；
Step S3：Primary current i1Magnetic field is generated when passing through first side winding, according to Ampere circuit law：
Wherein, N1The number of turns, N for first winding2It is the effective magnetic conduction length of iron core, i for the number of turns of secondary winding, L2For
Secondary current；
Step S4：For the secondary side of current transformer, according to the law of electromagnetic induction：
Trapezoidal Bei Ruilong integration methods are used to above formula, in adjacent spaces time Δ t, magnetic flux and secondary current i2Relationship
It is shown below：
Wherein, A is magnetic conduction cross-sectional area, the R of iron core2For secondary winding and the all-in resistance of secondary load, L2For it is secondary around
The total inductance of group and secondary load；
Step S5：Due to secondary current value it is known that being obtained by the relational expression of magnetic flux and secondary current in the step S4
The size of Δ B in adjacent spaces time Δ t；First moment magnetic induction intensity of note is arbitrary value B(1), then second moment magnetic strength
The intensity size is answered to be：
B(2)=B(1)+ΔB(1)
Hereafter the magnetic induction intensity at each moment adds the difference DELTA of magnetic induction on the magnetic induction intensity of previous moment
B(n-1), as follows：
B(n)=B(n-1)+ΔB(n-1)
Obtain the magnetic induction density B at n-th of moment(n), by regarding H as X-axis, using B as Y-axis, obtain magnetic hysteresis and return
Line.
In an embodiment of the present invention, it can be obtained by the relational expression of magnetic flux and secondary current in the step S4, in the step
In rapid S5, for arbitrary neighborhood interval time, Δ B is and initial value B(1)Unrelated amount, in the case of normal operation is stablized,
Actual initial value is B '(1)：
Wherein, BmaxFor maximum magnetic induction in a cycle, BminFor minimum magnetic induction intensity in a cycle, utilize
Initial value B '(1)Act on behalf of B(1)Bring formula B into(n)=B(n-1)+ΔB(n-1)It recalculates, obtains the corresponding B values of each moment H.
In an embodiment of the present invention, in the step S1, the digital oscilloscope bandwidth is more than or equal to 100MHz；
During the digital oscilloscope use, the primary current and the secondary current be about the symmetrical waveforms of time shaft t,
And storage format is csv formats.
Compared to the prior art, the invention has the advantages that：A kind of current transformer magnetic proposed by the invention
Hysteresis curves observation procedure, the magnetic hysteresis information for including using first and second electric current of current transformer obtain hysteresis loop, can quickly letter
Just realization current transformer hysteresis loop observation, it may be convenient to observe the limit hysteresis loop under CT saturation
The hysteresis loop under current transformer unsaturation can easily be observed.It avoids separately testing for observation hysteresis loop, Ke Yifang
Being observed to having made molding current transformer hysteresis loop just, is particularly suitable for current transformer core hysteresis loop
Frequency characteristic is observed.
Description of the drawings
Fig. 1 is Hall process measuring principle figure.
Fig. 2 is RC oscilloscope method schematic diagrams.
Fig. 3 is the low-voltage current mutual inductor connection diagram of 5/50 circle used in the embodiment of the present invention.
Fig. 4 is for mesolow of embodiment of the present invention current transformer by the current transformer after digital oscilloscope recording in iron
First and second current waveform when core is saturated.
Hysteresis loop schematic diagram when Fig. 5 is core sataration in the embodiment of the present invention.
Iron-core magnetic induction intensity schematic diagram when Fig. 6 is core sataration in the embodiment of the present invention.
Iron core intensity of magnetization schematic diagram when Fig. 7 is core sataration in the embodiment of the present invention.
Specific implementation mode
Below in conjunction with the accompanying drawings, technical scheme of the present invention is specifically described.
The present invention provides a kind of current transformer hysteresis loop observation procedure.Current transformer primary current is returned by magnetic hysteresis
Line converts to obtain secondary current.In hysteresis loop unsaturation, secondary current is really an approximate sinusoidal waveform, in magnetic hysteresis
Secondary current is being not near sinusoidal waveform when loop line is saturated.No matter it is saturated or unsaturated, first and second current transformer all wraps
The information of iron core hysteresis loop is contained.The purpose of current transformer hysteresis loop numerical method be using current transformer one,
The waveform that secondary current changes over time intuitively shows iron core hysteresis loop phenomenon.In order to form magnetic in relatively low experimental voltage
Hysteresis curves are in the present embodiment the low-voltage current mutual inductor of 5/50 circle as shown in Figure 3, and secondary load is 10 Ω, power supply frequency
Rate is 50Hz, and iron core is silicon steel sheet, iron core internal diameter d1=38mm, iron core outside diameter d2=53mm, iron core width d3=23mm, lamination
Thickness d4=0.23mm.Primary side current is directly acquired using digital oscilloscope current probe, is measured using voltage probe secondary
Secondary current is then converted to after resistive voltage.
By digital oscilloscope while sampling current transformer primary current, secondary current, by the one of oscillograph recording, two
Primary current and time import the data processing softwares such as Matlab.
Primary current i1Magnetic field is generated when passing through first side winding, according to Ampere circuit law：
Wherein, N1The number of turns, N for first winding2It is the effective magnetic conduction length of iron core, i for the number of turns of secondary winding, L2For
Secondary current；
For the secondary side of current transformer, according to the law of electromagnetic induction：
Trapezoidal Bei Ruilong integration methods are used to above formula, in adjacent spaces time Δ t, magnetic flux and secondary current i2Relationship
It is shown below：
Wherein, A is magnetic conduction cross-sectional area, the R of iron core2For secondary winding and the all-in resistance of secondary load, L2For it is secondary around
The total inductance of group and secondary load；
Due to secondary current value it is known that obtaining adjacent spaces time Δ by the relational expression of magnetic flux in above formula and secondary current
The size of Δ B in t；First moment magnetic induction intensity of note is arbitrary value B(1), then second moment induction level be：
B(2)=B(1)+ΔB(1)
Hereafter the magnetic induction intensity at each moment adds the difference DELTA of magnetic induction on the magnetic induction intensity of previous moment
B(n-1), as follows：
B(n)=B(n-1)+ΔB(n-1)
Obtain the magnetic induction density B at n-th of moment(n), by regarding H as X-axis, using B as Y-axis, obtain magnetic hysteresis and return
Line.
For arbitrary neighborhood interval time, Δ B is initial value B(1)Unrelated amount, it is real in the case of normal operation is stablized
The initial value on border is B '(1)：
Wherein, BmaxFor maximum magnetic induction in a cycle, BminFor minimum magnetic induction intensity in a cycle, utilize
Initial value B '(1)Act on behalf of B(1)Bring formula B into(n)=B(n-1)+ΔB(n-1)It recalculates, obtains the corresponding B values of each moment H.
Further, in the present embodiment, the digital oscilloscope bandwidth is more than or equal to 100MHz；In the digital oscillography
During device use, the primary current and the secondary current are about the symmetrical waveforms of time shaft t, and storage format is
Csv formats.
Further, in the present embodiment, Fig. 4 show the low-voltage current mutual inductor of 5/50 circle and is recorded by digital oscilloscope
First and second current waveform of the current transformer when hysteresis loop is saturated after wave.Method obtains in technical solution through the invention
Hysteresis loop is as shown in Fig. 5~7 when the core sataration arrived.
The above are preferred embodiments of the present invention, all any changes made according to the technical solution of the present invention, and generated function is made
When with range without departing from technical solution of the present invention, all belong to the scope of protection of the present invention.
Claims (3)
1. a kind of current transformer hysteresis loop observation procedure, which is characterized in that realize in accordance with the following steps：
Step S1：The primary current of primary side is directly acquired using digital oscilloscope current probe；Utilize the digital oscilloscope
After voltage probe measures secondary resistive voltage, it is then converted to secondary current；
Step S2：The primary current acquired, the secondary current and time are subjected to data processing by Matlab；
Step S3：Primary current i1Magnetic field is generated when passing through first side winding, according to Ampere circuit law：
Wherein, N1The number of turns, N for first winding2It is the effective magnetic conduction length of iron core, i for the number of turns of secondary winding, L2It is secondary
Electric current；
Step S4：For the secondary side of current transformer, according to the law of electromagnetic induction：
Trapezoidal Bei Ruilong integration methods are used to above formula, in adjacent spaces time Δ t, magnetic flux and secondary current i2Relationship it is as follows
Shown in formula：
Wherein, A is magnetic conduction cross-sectional area, the R of iron core2For secondary winding and the all-in resistance of secondary load, L2For secondary winding with
The total inductance of secondary load；
Step S5：Due to secondary current value it is known that being obtained by the relational expression of magnetic flux and secondary current in the step S4 adjacent
The size of Δ B in interval time Δ t；First moment magnetic induction intensity of note is arbitrary value B(1), then second moment magnetic induction is strong
Spending size is：
B(2)=B(1)+ΔB(1)
Hereafter the magnetic induction intensity at each moment adds the difference DELTA B of magnetic induction on the magnetic induction intensity of previous moment(n-1),
It is as follows：
B(n)=B(n-1)+ΔB(n-1)
Obtain the magnetic induction density B at n-th of moment(n), by regarding H as X-axis, using B as Y-axis, obtain hysteresis loop.
2. a kind of current transformer hysteresis loop observation procedure according to claim 1, which is characterized in that by the step
The relational expression of magnetic flux and secondary current can obtain in S4, in the step S5, for arbitrary neighborhood interval time, Δ B be with just
Initial value B(1)Unrelated amount, in the case of normal operation is stablized, actual initial value is B '(1)：
Wherein, BmaxFor maximum magnetic induction in a cycle, BminFor minimum magnetic induction intensity in a cycle, using initial
Value B '(1)Instead of B(1)Bring formula B into(n)=B(n-1)+ΔB(n-1)It recalculates, obtains the corresponding B values of each moment H.
3. a kind of current transformer hysteresis loop observation procedure according to claim 1, which is characterized in that in the step
In S1, the digital oscilloscope bandwidth is more than or equal to 100MHz；During the digital oscilloscope use, the primary current with
And the secondary current is about the symmetrical waveforms of time shaft t, and storage format is csv formats.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101004441A (en) * | 2007-01-25 | 2007-07-25 | 上海交通大学 | Method for measuring coefficient of residual magnetism based on alternating current method |
| CN101520495A (en) * | 2009-03-02 | 2009-09-02 | 重庆大学 | Device for mapping magnetizing characteristic curve of ferromagnetic materials and mapping method thereof |
| CN101539611A (en) * | 2009-04-29 | 2009-09-23 | 太原理工大学 | Measuring method for switched reluctance motor winding mutual inductance |
| CN101858963A (en) * | 2009-04-08 | 2010-10-13 | 常州信息职业技术学院 | Method for measuring static magnetic characteristic |
| CN102621507A (en) * | 2012-04-14 | 2012-08-01 | 河北工业大学 | Obtaining method of direct current magnetic biasing hysteresis loop of transformer core material |
| CN103091651A (en) * | 2013-01-24 | 2013-05-08 | 江西理工大学 | Ballistic galvanometer measuring hysteresis loop of ferromagnetic medium method |
-
2015
- 2015-11-12 CN CN201510769400.3A patent/CN105301532B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101004441A (en) * | 2007-01-25 | 2007-07-25 | 上海交通大学 | Method for measuring coefficient of residual magnetism based on alternating current method |
| CN101520495A (en) * | 2009-03-02 | 2009-09-02 | 重庆大学 | Device for mapping magnetizing characteristic curve of ferromagnetic materials and mapping method thereof |
| CN101858963A (en) * | 2009-04-08 | 2010-10-13 | 常州信息职业技术学院 | Method for measuring static magnetic characteristic |
| CN101539611A (en) * | 2009-04-29 | 2009-09-23 | 太原理工大学 | Measuring method for switched reluctance motor winding mutual inductance |
| CN102621507A (en) * | 2012-04-14 | 2012-08-01 | 河北工业大学 | Obtaining method of direct current magnetic biasing hysteresis loop of transformer core material |
| CN103091651A (en) * | 2013-01-24 | 2013-05-08 | 江西理工大学 | Ballistic galvanometer measuring hysteresis loop of ferromagnetic medium method |
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