CN103760399A

CN103760399A - Method for manufacturing Hall current sensor by using ferrite and Hall current sensor

Info

Publication number: CN103760399A
Application number: CN201310754265.6A
Authority: CN
Inventors: 叶伟; 张卫东; 顾燮峰; 黄子谦; 彭中华; 刘晓东
Original assignee: SHANGHAI BAO STEEL MAGNETICS CO Ltd
Current assignee: SHANGHAI BAO STEEL MAGNETICS CO Ltd
Priority date: 2013-12-31
Filing date: 2013-12-31
Publication date: 2014-04-30

Abstract

The invention discloses a method for manufacturing a Hall current sensor by using ferrite and the Hall current sensor and belongs to the field of electrons and materials. According to the method for manufacturing the Hall current sensor by using the ferrite and the Hall current sensor, the ferrite is used for manufacturing the ring type Hall current sensor. The method for manufacturing the Hall current sensor by using the ferrite specifically comprises the steps that a circular ring type iron core is made of the ferrite instead of the conventional permalloy, the physical characteristic, the static electrical characteristic and the magnetic-lag coefficient of the ferrite completely meet the use requirements of the Hall current sensor, the maximum frequency of utilization reaches 2MHz, and high frequency use requirements of the sensor are completely met. The price of raw materials of the ferrite is low, the manufacturing technology is simple, and the price is low; the manufacturing technology is simple compared with a manufacturing technology using the permalloy, the market prospect is broad, and the potential is huge.

Description

Ferrite is for the preparation of Hall current sensor and a kind of Hall current sensor

Technical field

The invention belongs to electronics and Material Field, relate to magnetic field sensor, be specially ferrite as preparing Hall current sensor.

Background technology

Hall current sensor is a kind of magnetic field sensor of making according to Hall effect, generally be divided into two kinds of open loop type and closed loops, can be widely used in the every field such as frequency control, accumulator detection, photovoltaic DC-to-AC converter, photovoltaic combiner box, frequency converter, electric welding machine, direct current generator driving detection, welding machine electric power, reactive-load compensation, electric automobile, servomotor, uninterrupted power source UPS, inverter.Because energization solenoid inside exists magnetic field, its size is directly proportional to the electric current in wire, thus can utilize Hall element to measure magnetic field, thus determine the size of electric current in wire.Utilize this principle to design and make Hall current sensor.

The advantage of Hall current sensor is not electrically contact with circuit-under-test, does not affect circuit-under-test, does not consume the power of tested power supply, is particularly suitable for large current sense.As shown in Figure 1, standard circle ring iron core has a breach to Hall current sensor principle of work, and Hall sensor element is inserted in breach, is wound with coil on annulus, and when electric current produces magnetic field during by coil, Hall element has signal output.

And by iron core material, require (1) magnetic permeability high to gather fast magnetic as Hall current sensor; (2) temperature coefficient is the smaller the better; (3) Steinmetz's constant wants high.In view of above requirement, Hall current sensor is generally selected permalloy by iron core material.The feature of permalloy refers to that nickel content is 35%-90% and contains the high magnetic permeability Rhometal of other alloying element on a small quantity,, and famous, its saturation induction density (Bs) is generally between 0.6-1.0T under low-intensity magnetic field, higher magnetoconductivity and low coercive force (Hc).

Hall current sensor future developing trend has following feature:

1) high sensitivity, the intensity of detected signal more and more a little less than, this will transducer sensitivity be greatly improved.

2) less temperature stability, more application requires the working environment of sensor more and more harsher, and this just requires Magnetic Sensor must have good temperature stability, and sector application comprises Automobile Electronic Industry.

3) higher anti-interference, a lot of fields are as automotive electronics, water meter etc., and the environment for use of sensor, without any shielding, just requires sensor itself to have good anti-interference.

4) miniaturization, integrated, intelligent, wants to accomplish above demand, and this just needs the integrated of chip-scale, and module level is integrated, and Product-level is integrated.

5) low-loss, a lot of fields require the power consumption of sensor itself extremely low, are extended the serviceable life of sensor.

6) high frequency characteristics, along with the popularization of application, requires the frequency of operation of sensor more and more higher, and application comprises water meter, Automobile Electronic Industry, information recording industry.

7) low cost, due to domestic production sensor, manufacturer is more, and it is main mainly producing low-and-medium-grade products, dog-eat-dog, rate war grows in intensity, the low-cost focus of attention of productive consumption electronic product enterprise especially.

Due to Hall element high frequency, low-loss, development trend cheaply, limit permalloy and used field, there are following two inferior positions in it:

(1) frequency of utilization is low, is difficult to adapt to the requirement of high frequency.

Permalloy, owing to being subject to its manufacturing process restriction, generally can only be rolled into 0.02-0.2mm thickness, and 0.2mm thickness can only be for 50Hz, and thinner can apply to power frequency and intermediate frequency, and maximum useful frequency maximum also can only 100KHz.As use high frequency, and the inferior position of permalloy just embodies, and because its resistivity is low, loss obviously increases, and has limited the use field of permalloy at high-frequency range.

The production run more complicated of permalloy.For example, cooling speed after the technique of plate rolling, annealing temperature, time, annealing etc. all has a significant impact the final magnetic property of material.

(2) expensive

The feature of permalloy is under low-intensity magnetic field, to have higher magnetoconductivity, and this characteristic surpasses even FERRITE CORE of common ferrosilicon iron core.But manufacturing one of permalloy starting material nickel is rare metal, expensive, in addition complex process is various, so permalloy iron core price is very expensive, generally only be applied in small-signal amplifying return circuit or specialities and the high-grade consumer market such as automobile, general low side consumer electronics product is difficult to set foot in.

Due to above two reasons, many electronics production firm, in order to adapt to market trend, suddenly waits to seek a kind of new material iron core and substitutes current permalloy iron core.

Summary of the invention

The present invention aims to provide a kind of Hall current sensor, with high frequencyization and cheaply FERRITE CORE replace the solution of permalloy iron core to adapt to transducer market development trend.

The present invention as preparing open loop type Hall current sensor, specifically adopts ferrite as the material of circle ring iron core in open loop type Hall current sensor iron oxygen alloy.

Open loop type Hall current sensor, structure comprises Hall element and circle ring iron core, has a breach on circle ring iron core, Hall element is inserted in breach; And winding around on circular iron hoop.The material of circle ring iron core adopts ferrite.

Ferrite Material is prepared by the following method: will comprise Fe ₂o ₃67%～72%, Mn ₃o ₄16%～19% and the raw material mixing of ZnO11%～15%, pre-burning, sand milling, granulation after at 1300～1500 ℃ sintering 25～35 hours, above-mentioned number percent is mass percent.

Preferably, described raw material is by 68.5%～71%Fe ₂o ₃, 16.5%～18%Mn ₃o ₄form with 12.5%～13.5%ZnO, above-mentioned number percent is mass percent.

Described sintering carries out in nitrogen kiln, and described calcined temperature is 700～100 ℃, and the time is 2～5 hours.

Preferred, described ferrite is Ferrite Material 5K5, and raw material is by 69.3wt%Fe ₂o ₃, 17.70wt%Mn ₃o ₄, 13.00wt%ZnO forms.

Find after deliberation, ferrite physics, static electrical characteristic and Steinmetz's constant meet Hall current sensor request for utilization completely, and particularly ferrite 5K5 maximum useful frequency reaches 2MHz, completely adapts to the high frequency request for utilization of sensor.

Ferritic starting material are used di-iron trioxide, mangano-manganic oxide, zinc paste, raw-material low price, and manufacturing process is simple, cheap; Manufacturing process is relatively simple compared with permalloy, and same specification FERRITE CORE price is 1/10th of permalloy iron core.

Comprehensively above-mentioned, it is completely possible that FERRITE CORE substitutes permalloy iron core, and has wide market outlook, has a high potential.

Accompanying drawing explanation

Fig. 1 is structure and the principle schematic of open loop type Hall current sensor

1-circle ring iron core, 101-breach, 2-Hall sensor element, 3-coil

Fig. 2 is the magnetic hysteresis loop of ferrite magnetic core material 5K5

Fig. 3 is temperature characterisitic and the frequency characteristic comparison of the prepared ferrite magnetic core material 5K5 of embodiment 1 and permalloy core material

Embodiment

Embodiment 1

Di-iron trioxide 69.3wt%, zinc paste 13.00wt%, mangano-manganic oxide 17.70wt% are weighed after mixing, at 800 ℃, pre-burning is 3 hours, after sand milling, granulation, make particulate material, after being placed on mould, suppress H16.8(external diameter) * 11(internal diameter) * 3.9(height) green compact (unit is millimeter), be placed on nitrogen kiln inherent 1400 ℃ through 32 hours sintering, obtain ferrite 5K5.Sintering electrical performance data is as table 1 and table 2:

Table 1

Power consumption (kw/cm3)

Table 2

Die mould data: 2.95 grams of weight, compact dimensions 4.58mm, density 2.97g/cm ³.Grinding data: cutting air gap 0.16mm, outward appearance non-notch.

Embodiment 2

The iron oxygen alloy 5K5 magnetic hysteresis loop of embodiment 1 as shown in Figure 2.The ferrite 5K5 of embodiment 1 and physics and the DC characteristic of permalloy material are as shown in table 3.

Table 3 permalloy material and ferrite 5K5 physics and DC characteristic

The performance that detects the Ferrite Material 5K5 of permalloy, Ferrite Material 3KDW and embodiment 1, result as shown in Figure 3.

From table 3, Fig. 2 and Fig. 3, the physics of ferrite 5K5, static electrical characteristic and Steinmetz's constant meet Hall current sensor request for utilization completely, and particularly ferrite 5K5 maximum useful frequency reaches 2MHz, adapt to the high frequency request for utilization of sensor completely.

Use respectively the Ferrite Material 5K5 of permalloy, Ferrite Material 3KDW and embodiment 1 to be used for preparing open loop type Hall current sensor.Structure as shown in Figure 1, the circle ring iron core 1 that comprises a standard, wherein having a breach 101(is air gap), Hall sensor element 2 is inserted in breach, be the primary structure of open loop type Hall current sensor, said structure is placed in to shell, and wire to be measured is wrapped in and on standard circle ring iron core 1, forms coil 3, the magnitude of current in can magnetic test coil.

The material of standard circle ring iron core adopts respectively the ferrite 5K5 of permalloy and embodiment 1.Result shows, while adopting embodiment 1 ferrite 5K5 as the material of the standard circle ring iron core of open loop type Hall current sensor, resulting open loop type Hall current sensor with adopt the open loop type Hall current sensor detection effect of permalloy identical; And still can have and detect accurately effect under the frequency of 2MHz.

Claims

1. ferrite is in the application of preparing aspect open loop type Hall current sensor.

2. described in claim 1, ferrite, in the application of preparing aspect open loop type Hall current sensor, is characterized in that, described ferrite is prepared by the following method:

To comprise Fe ₂o ₃67%～72%, after the raw material mixing of Mn3O416%～19% and ZnO11%～15%, pre-burning, sand milling, granulation at 1350～1500 ℃ sintering 30～35 hours, above-mentioned number percent is mass percent.

3. described in claim 2, ferrite, in the application of preparing aspect open loop type Hall current sensor, is characterized in that, described raw material is by 68.5%～71%Fe ₂o ₃, 16.5%～18%Mn ₃o ₄form with 12.5%～13.5%ZnO, above-mentioned number percent is mass percent.

4. described in claim 2, iron oxygen alloy, in the application of preparing aspect Hall current sensor, is characterized in that, described sintering carries out in nitrogen kiln; Described calcined temperature is 700～100 ℃, and the time is 2～5 hours.

5. described in claim 1, ferrite, in the application of preparing aspect Hall current sensor, is characterized in that described ferrite chosen from Fe ferrite 5K5.

6. an open loop type Hall current sensor, comprises Hall element and circle ring iron core, it is characterized in that, the material of described circle ring iron core is ferrite.

7. open loop type Hall current sensor described in claim 6, is characterized in that, described ferrite is prepared by the following method: will comprise Fe ₂o ₃67%～72%, Mn ₃o ₄16%～19% and the raw material mixing of ZnO11%～15%, pre-burning, sand milling, granulation after at 1300～1500 ℃ sintering 25～35 hours, above-mentioned number percent is mass percent.

8. open loop type Hall current sensor described in claim 6 or 7, is characterized in that, described raw material is by 68.5%～71%Fe ₂o ₃, 16.5%～18%Mn ₃o ₄form with 12.5%～13.5%ZnO, above-mentioned number percent is mass percent.

9. open loop type Hall element described in claim 7, is characterized in that, described sintering carries out in nitrogen kiln, and described calcined temperature is 700～100 ℃, and the time is 2～5 hours.

10. open loop type Hall element described in claim 5, is characterized in that, described ferrite is Ferrite Material 5K5.