CN203606476U - System for measuring magnetic characteristics of silicon steel sheet under excitation of PWM power supply - Google Patents
System for measuring magnetic characteristics of silicon steel sheet under excitation of PWM power supply Download PDFInfo
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- CN203606476U CN203606476U CN201320797269.8U CN201320797269U CN203606476U CN 203606476 U CN203606476 U CN 203606476U CN 201320797269 U CN201320797269 U CN 201320797269U CN 203606476 U CN203606476 U CN 203606476U
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- 230000005284 excitation Effects 0.000 title claims abstract description 14
- 229910000976 Electrical steel Inorganic materials 0.000 title abstract description 10
- 230000004907 flux Effects 0.000 claims abstract description 58
- 238000009413 insulation Methods 0.000 claims abstract description 21
- 230000001681 protective effect Effects 0.000 claims abstract description 18
- 238000004804 winding Methods 0.000 claims abstract description 12
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 19
- 229910052802 copper Inorganic materials 0.000 claims description 17
- 239000010949 copper Substances 0.000 claims description 17
- 238000013481 data capture Methods 0.000 claims description 9
- 238000004519 manufacturing process Methods 0.000 abstract description 5
- 238000012545 processing Methods 0.000 abstract description 3
- 238000002955 isolation Methods 0.000 abstract 5
- 239000002023 wood Substances 0.000 abstract 1
- 238000000034 method Methods 0.000 description 10
- 238000005259 measurement Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 238000012423 maintenance Methods 0.000 description 2
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
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Abstract
The utility model discloses a system for measuring magnetic characteristics of a silicon steel sheet under excitation of a PWM power supply. The system comprises a control computer, a data acquisition card, a low-pass filter, a power amplifier, an isolation transformer, a magnetic yoke, an excitation winding, a laminated wood padding block, a coil bracket, a protective sleeve, a magnetic flux density measuring coil, a coil insulation framework, a first magnetic field intensity measuring coil and a second magnetic field intensity measuring coil, wherein the excitation winding is connected to the isolation transformer, the magnetic flux density measuring coil is connected to the data acquisition card through a first isolation amplifier, the first magnetic field intensity measuring coil is connected to the data acquisition card through a second isolation amplifier, and the second magnetic field intensity measuring coil is connected to the data acquisition card through a third isolation amplifier. The system disclosed by the utility model is simple in structure, the winding is low in processing difficulty, an air compensating coil is saved, and the manufacturing cost of the system is reduced.
Description
Technical field
The utility model relates to Techniques in Electromagnetic Measurement field, specifically refers to a kind of PWM(Pulse Width Modulation, pulse-length modulation) the power supply excitation measuring system of siliconized plate magnetic characteristic down.
Background technology
Traditional siliconized plate magnetic characteristic measuring system, magnetic flux density reference waveform in silicon steel print is sinusoidal wave, but, because the magnetic flux density waveform in a lot of electrical equipment iron cores is that various higher hamonic waves are formed by stacking, cause the loss producing in siliconized plate larger, therefore, traditional measurement method can't reflect practical operation situation unshakable in one's determination.For the problem existing in above-mentioned traditional measurement system, BROCKHAUS company of Germany has produced the measurement mechanism of a kind of pair of yoke structure, but its complex structure, measuring coil and field coil are all wound on coil rack, there is leakage field phenomenon, need additional compensated with air coil, and the maintenance of inconvenient field copper and measuring coil and maintenance.
Utility model content
The purpose of this utility model is to provide the measuring system of the lower siliconized plate magnetic characteristic of a kind of PWM power supply excitation, the simple in measurement system structure of this siliconized plate magnetic characteristic, winding processing and manufacturing difficulty is low, in measuring coil in this system, almost do not have leakage flux to pass through, save compensated with air coil, reduced the manufacturing cost of system.
For realizing this object, the designed PWM power supply of the utility model encourages the measuring system of lower siliconized plate magnetic characteristic, it comprises the first isolated amplifier, the second isolated amplifier, the 3rd isolated amplifier and the control computing machine connecting successively, data collecting card, low-pass filter, power amplifier and isolating transformer, it is characterized in that: it also comprises C type yoke, respectively around two field copper at C type yoke both ends, be located at respectively two laminated wooden blocks of C type yoke both ends of the surface, be fixed on the magnetic field intensity measuring coil support of C type yoke open interior, be fixed on magnetic field intensity measuring coil support and the magnetic flux density measuring coil that can entangle tested siliconized plate, be fixed on the first magnetic field intensity measuring coil and the second magnetic field intensity measuring coil on magnetic field intensity measuring coil support, wherein, described the first magnetic field intensity measuring coil is positioned at the below of magnetic flux density measuring coil, described the second magnetic field intensity measuring coil is positioned at the below of the first magnetic field intensity measuring coil,
Described two field copper connect isolating transformer, the signal output part of described magnetic flux density measuring coil is by the signal input part of the first isolated amplifier access data capture card, the signal output part of the first magnetic field intensity measuring coil is by the signal input part of the second isolated amplifier access data capture card, and the signal output part of described the second magnetic field intensity measuring coil is by the signal input part of the 3rd isolated amplifier access data capture card.
In technique scheme, it also comprises winding insulation support, and described field copper is fixedly connected with C type yoke by winding insulation support.
Described magnetic field intensity measuring coil support is provided with supporting surface, and described supporting surface is provided with sponge, and the second magnetic field intensity measuring coil is set on described sponge, between described the second magnetic field intensity measuring coil and the first magnetic field intensity measuring coil, is also provided with sponge.
In technique scheme, it also comprises magnetic flux density measuring coil protective sleeve, and described magnetic flux density measuring coil is arranged on magnetic flux density measuring coil protective sleeve inside, and described magnetic flux density measuring coil protective sleeve is fixed on magnetic field intensity measuring coil support.
In technique scheme, it also comprises support and coil insulation framework, the inwall laminating of described coil insulation framework and magnetic flux density measuring coil, and described coil insulation framework is fixed in magnetic flux density measuring coil protective sleeve by support.
The two ends of described magnetic flux density measuring coil protective sleeve are equipped with baffle plate, on described two baffle plates, all offer groove, and tested siliconized plate is through the groove on baffle plate.
The advantage of the above-mentioned C type yoke of the utility model design is: save yoke manufacturing cost, reduce iron core weight, the shape of above-mentioned yoke is conducive to the suit of field copper, compared with the single sheet measurement device of existing pair of magnetic yoke structure, save upper magnet yoke, and can save the mechanical hook-up of adjusting upper magnet yoke height.
The utility model by by field copper in C type yoke, avoided in existing equipment field copper around the winding processing and manufacturing bringing on tested siliconized plate and the difficulty of suit.
In the utility model, magnetic flux density measuring coil is close to the coiling of tested silicon steel print by coil insulation framework, its advantage is: magnetic flux density measuring coil is close to tested silicon steel print, making does not almost have leakage flux to pass through in magnetic flux density measuring coil, save compensated with air coil, loop construction is simple.
The utility model adopts the first magnetic field intensity measuring coil and the second magnetic field intensity measuring coil.Its advantage is: by by 2 measurement points by linear extension, obtain the magnetic field intensity of tested silicon steel print inside, improve the measuring precision.
The utility model adopts the compression mode of laminated wooden block, and tested silicon steel print is close in yoke.Its advantage is: by reducing the air gap between tested silicon steel print and yoke, can reduce exciting current, and improve the magnetic flux density in tested silicon steel print.
Accompanying drawing explanation
Fig. 1 is measuring system theory diagram of the present utility model;
Fig. 2 is measurement mechanism structural representation of the present utility model;
Fig. 3 is the side view of Fig. 2;
Fig. 4 is the vertical view of Fig. 2;
Fig. 5 is the sectional structure schematic diagram of A-A ' part in Fig. 2;
Fig. 6 is that the B-B ' of Fig. 3 is to sectional structure schematic diagram.
Wherein, 1-control computing machine, 2-data collecting card, 3-low-pass filter, 4-power amplifier, 5-isolating transformer, the 6-the first isolated amplifier, the 7-the second isolated amplifier, the 8-the three isolated amplifier, 9-tested siliconized plate, the 10-the first magnetic field intensity measuring coil, 11-sponge, 12-laminated wooden block, the 13-the second magnetic field intensity measuring coil, 14-magnetic field intensity measuring coil support, 15-C type yoke, 16-field copper, 17-winding insulation support, 18-magnetic flux density measuring coil, 19-coil insulation framework, 20-magnetic flux density measuring coil protective sleeve, 21-support, 22-baffle plate, 22.1-groove, 23-supporting surface.
Embodiment
Below in conjunction with the drawings and specific embodiments, the utility model is described in further detail:
The designed PWM power supply of the utility model encourages the measuring system of lower siliconized plate magnetic characteristic, as shown in Fig. 1～6, it comprises the first isolated amplifier 6, the second isolated amplifier 7, the 3rd isolated amplifier 8 and the control computing machine 1 connecting successively, data collecting card 2, low-pass filter 3, power amplifier 4 and isolating transformer 5, it also comprises C type yoke 15, respectively around two field copper 16 at C type yoke 15 both ends, be located at respectively two laminated wooden blocks 12 of C type yoke 15 both ends of the surface, be fixed on the magnetic field intensity measuring coil support 14 of C type yoke 15 open interior, be fixed on magnetic field intensity measuring coil support 14 and the magnetic flux density measuring coil 18 that can entangle tested siliconized plate 9, be fixed on the first magnetic field intensity measuring coil 10 and the second magnetic field intensity measuring coil 13 on magnetic field intensity measuring coil support 14, wherein, described the first magnetic field intensity measuring coil 10 is positioned at the below of magnetic flux density measuring coil 18, described the second magnetic field intensity measuring coil 13 is positioned at the below of the first magnetic field intensity measuring coil 10,
Described two field copper 16 connect isolating transformer 5, the signal output part of described magnetic flux density measuring coil 18 is by the signal input part of the first isolated amplifier 6 access data capture cards 2, the signal output part of the first magnetic field intensity measuring coil 10 is by the signal input part of the second isolated amplifier 7 access data capture cards 2, and the signal output part of described the second magnetic field intensity measuring coil 13 is by the signal input part of the 3rd isolated amplifier 8 access data capture cards 2.
In technique scheme, it also comprises winding insulation support 17, and described field copper 16 is fixedly connected with C type yoke 15 by winding insulation support 17.
In technique scheme, described magnetic field intensity measuring coil support 14 is provided with supporting surface 23, described supporting surface 23 is provided with sponge 11, the second magnetic field intensity measuring coil 13 is set on described sponge 11, between described the second magnetic field intensity measuring coil 13 and the first magnetic field intensity measuring coil 10, is also provided with sponge 11.Above-mentioned sponge 11, for the protection of magnetic field intensity measuring coil, avoids measuring coil to damage.
In technique scheme; it also comprises magnetic flux density measuring coil protective sleeve 20; described magnetic flux density measuring coil 18 is arranged on magnetic flux density measuring coil protective sleeve 20 inside, and described magnetic flux density measuring coil protective sleeve 20 is fixed on magnetic field intensity measuring coil support 14.Magnetic flux density measuring coil protective sleeve 20 is used for protecting magnetic flux density measuring coil 18, avoids magnetic flux density measuring coil 18 destroyed being short-circuited of insulating.
In technique scheme, it also comprises support 21 and coil insulation framework 19, and described coil insulation framework 19 is fitted with the inwall of magnetic flux density measuring coil 18, and described coil insulation framework 19 is fixed in magnetic flux density measuring coil protective sleeve 20 by support 21.Described coil insulation framework 19 can be avoided tested siliconized plate 9 colliding with to its generation in the time putting into magnetic flux density measuring coil 18.
In technique scheme, the two ends of described magnetic flux density measuring coil protective sleeve 20 are equipped with baffle plate 22, on described two baffle plates 22, all offer groove 22.1, and tested siliconized plate 9 is through the groove 22.1 on baffle plate 22.
When the utility model uses, tested siliconized plate 9 is penetrated to groove 22.1 and coil insulation framework 19, the two ends of the tested siliconized plate 9 respectively end face corresponding with C type yoke 15 fully contact, and then on tested siliconized plate 9, place laminated wooden block 12, and tested siliconized plate 9 is pressed in C type yoke 15.
The siliconized plate magnetic characteristic measuring method of utilizing above-mentioned measuring system, comprises the steps:
Step 1: load the PWM voltage of specifying in field copper 16, make to produce magnetic flux in tested siliconized plate 9;
Step 2: measure magnetic flux density and the magnetic field intensity in tested siliconized plate 9 by magnetic flux density measuring coil 18, the first magnetic field intensity measuring coil 10 and the second magnetic field intensity measuring coil 13;
Step 3: when the magnetic flux density in tested siliconized plate 9 does not reach capacity, extract magnetic flux density waveform, and it is done to Fourier decomposition, obtain the percentage composition of each harmonic;
Step 4: by changing PWM voltage waveform, until the fundametal compoment in tested siliconized plate 9 is sinusoidal variations, form factor is controlled at 1.111 ± 1%, other harmonic component ratio is pressed harmonic component number percent in initial waveform and is adjusted, and deviation control is ± 1%;
Step 5: adjust PWM voltage waveform amplitude, repeating step 1～step 3, obtains magnetic hysteresis loop and damage curve that one group of fundamental flux density amplitude changes from small to large.
The utility model utilization control computing machine 1 produces PWM wave voltage control signal, exported by data collecting card 2, suppress high frequency noise through low-pass filter 3, through power amplifier 4, field voltage amplitude is elevated to specifying magnetic flux density and is mated, utilize isolating transformer 5 to avoid the electrical connection between power amplifier 4 and field copper 16, play the effect of protection instrument, field voltage is added in field copper 16, then by magnetic flux density measuring coil 18, induced voltage signal in the first magnetic field intensity measuring coil 10 and the second magnetic field intensity measuring coil 13 is respectively by the first isolated amplifier 6, the second isolated amplifier 7 and the 3rd isolated amplifier 8 are amplified in the resolving range of data collecting card 2, deliver to again data collecting card 2, do integration and obtain the waveform of magnetic flux density and magnetic field intensity through software.First, adding field voltage makes tested silicon steel print in unsaturation state, magnetic flux density waveform is done to Fourier decomposition, obtain the percentage composition of each harmonic, under the excitation of PWM voltage waveform, in magnetic flux density waveform, the percentage composition of first-harmonic is much larger than all the other each harmonics, therefore, the waveform that only need adjust by feedback system fundamental flux density, is controlled at form factor in 1.111 ± 1% scopes.Record magnetic hysteresis loop and loss value now.By changing voltage magnitude, obtain one group of magnetic hysteresis loop and damage curve.
The content that this instructions is not described in detail belongs to the known prior art of professional and technical personnel in the field.
Claims (6)
1. the measuring system of the lower siliconized plate magnetic characteristic of PWM power supply excitation, it comprises the first isolated amplifier (6), the second isolated amplifier (7), the 3rd isolated amplifier (8) and the control computing machine (1) connecting successively, data collecting card (2), low-pass filter (3), power amplifier (4) and isolating transformer (5), it is characterized in that: it also comprises C type yoke (15), respectively around two field copper (16) at C type yoke (15) both ends, be located at respectively two laminated wooden blocks (12) of C type yoke (15) both ends of the surface, be fixed on the magnetic field intensity measuring coil support (14) of C type yoke (15) open interior, be fixed on the magnetic flux density measuring coil (18) that magnetic field intensity measuring coil support (14) is upper and can entangle tested siliconized plate (9), be fixed on the first magnetic field intensity measuring coil (10) and the second magnetic field intensity measuring coil (13) on magnetic field intensity measuring coil support (14), wherein, described the first magnetic field intensity measuring coil (10) is positioned at the below of magnetic flux density measuring coil (18), described the second magnetic field intensity measuring coil (13) is positioned at the below of the first magnetic field intensity measuring coil (10),
Described two field copper (16) connect isolating transformer (5), the signal output part of described magnetic flux density measuring coil (18) is by the signal input part of the first isolated amplifier (6) access data capture card (2), the signal output part of the first magnetic field intensity measuring coil (10) is by the signal input part of the second isolated amplifier (7) access data capture card (2), and the signal output part of described the second magnetic field intensity measuring coil (13) is by the signal input part of the 3rd isolated amplifier (8) access data capture card (2).
2. the measuring system of the lower siliconized plate magnetic characteristic of PWM power supply excitation according to claim 1, it is characterized in that: it also comprises winding insulation support (17), described field copper (16) is fixedly connected with C type yoke (15) by winding insulation support (17).
3. the measuring system of the lower siliconized plate magnetic characteristic of PWM power supply excitation according to claim 1, it is characterized in that: described magnetic field intensity measuring coil support (14) is provided with supporting surface (23), described supporting surface (23) is provided with sponge (11), the second magnetic field intensity measuring coil (13) is set on described sponge (11), between described the second magnetic field intensity measuring coil (13) and the first magnetic field intensity measuring coil (10), is also provided with sponge (11).
4. according to the measuring system of the lower siliconized plate magnetic characteristic of PWM power supply excitation described in any one in claim 1～3; it is characterized in that: it also comprises magnetic flux density measuring coil protective sleeve (20); described magnetic flux density measuring coil (18) is arranged on magnetic flux density measuring coil protective sleeve (20) inside, and described magnetic flux density measuring coil protective sleeve (20) is fixed on magnetic field intensity measuring coil support (14).
5. the measuring system of the lower siliconized plate magnetic characteristic of PWM power supply excitation according to claim 4; it is characterized in that: it also comprises support (21) and coil insulation framework (19); described coil insulation framework (19) is fitted with the inwall of magnetic flux density measuring coil (18), and described coil insulation framework (19) is fixed in magnetic flux density measuring coil protective sleeve (20) by support (21).
6. the measuring system of the lower siliconized plate magnetic characteristic of PWM power supply excitation according to claim 5; it is characterized in that: the two ends of described magnetic flux density measuring coil protective sleeve (20) are equipped with baffle plate (22); on described two baffle plates (22), all offer groove (22.1), tested siliconized plate (9) is through the groove (22.1) on baffle plate (22).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320797269.8U CN203606476U (en) | 2013-12-05 | 2013-12-05 | System for measuring magnetic characteristics of silicon steel sheet under excitation of PWM power supply |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320797269.8U CN203606476U (en) | 2013-12-05 | 2013-12-05 | System for measuring magnetic characteristics of silicon steel sheet under excitation of PWM power supply |
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| CN203606476U true CN203606476U (en) | 2014-05-21 |
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| CN201320797269.8U Expired - Lifetime CN203606476U (en) | 2013-12-05 | 2013-12-05 | System for measuring magnetic characteristics of silicon steel sheet under excitation of PWM power supply |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105116357A (en) * | 2015-08-28 | 2015-12-02 | 武汉钢铁(集团)公司 | Steel coil DC magnetic performance measurement device and method |
| CN106842083A (en) * | 2017-02-28 | 2017-06-13 | 河北工业大学 | Wideband rotary magnetic characteristic measuring system and measuring method based on flexible magnetizing coil |
| CN108957368A (en) * | 2018-03-27 | 2018-12-07 | 中国电力科学研究院有限公司 | A kind of system and method measuring magnetic characteristic under silicon steel material D.C. magnetic biasing state |
| CN110297195A (en) * | 2019-07-29 | 2019-10-01 | 海南金盘电气研究院有限公司 | A kind of transformer core Distribution of Magnetic Field detection system |
| CN110542871A (en) * | 2019-10-10 | 2019-12-06 | 华北电力大学 | magnetic characteristic measurement system and method for magnetic material |
-
2013
- 2013-12-05 CN CN201320797269.8U patent/CN203606476U/en not_active Expired - Lifetime
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105116357A (en) * | 2015-08-28 | 2015-12-02 | 武汉钢铁(集团)公司 | Steel coil DC magnetic performance measurement device and method |
| CN106842083A (en) * | 2017-02-28 | 2017-06-13 | 河北工业大学 | Wideband rotary magnetic characteristic measuring system and measuring method based on flexible magnetizing coil |
| CN106842083B (en) * | 2017-02-28 | 2019-03-26 | 河北工业大学 | Wideband rotary magnetic characteristic measuring system and measurement method based on flexible magnetizing coil |
| CN108957368A (en) * | 2018-03-27 | 2018-12-07 | 中国电力科学研究院有限公司 | A kind of system and method measuring magnetic characteristic under silicon steel material D.C. magnetic biasing state |
| CN110297195A (en) * | 2019-07-29 | 2019-10-01 | 海南金盘电气研究院有限公司 | A kind of transformer core Distribution of Magnetic Field detection system |
| CN110542871A (en) * | 2019-10-10 | 2019-12-06 | 华北电力大学 | magnetic characteristic measurement system and method for magnetic material |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20170720 Address after: 430083, Hubei Wuhan Qingshan District Factory No. 2 Gate joint stock company organs Patentee after: WUHAN IRON AND STEEL Co.,Ltd. Address before: 430080 Wuchang, Hubei Friendship Road, No. A, block, floor 999, 15 Patentee before: WUHAN IRON AND STEEL (GROUP) Corp. |
|
| CX01 | Expiry of patent term | ||
| CX01 | Expiry of patent term |
Granted publication date: 20140521 |