CN201331400Y

CN201331400Y - Permanent magnet torquer

Info

Publication number: CN201331400Y
Application number: CNU200820144961XU
Authority: CN
Inventors: 刘晓东; 陈伟; 聂鲁燕
Original assignee: 707th Research Institute of CSIC
Current assignee: 707th Research Institute of CSIC
Priority date: 2008-12-26
Filing date: 2008-12-26
Publication date: 2009-10-21
Anticipated expiration: 2018-12-26

Abstract

The utility model relates to a permanent magnet torquer, which comprises a stator, a rotor, a magnetic-conductive ring and a compensation circuit, wherein, the stator, the rotor and the magnetic-conductive ring are arranged coaxially and centeredly; the stator comprises a permanent steel magnet and a stator magnet ring; the rotor comprises a current-carrying coil and a coil framework; the surface polarities N and S of the permanent steel magnet of the stator are uniformly distributed on the stator magnet ring in a crossing manner, and a closed-ring DC magnetic loop is formed through a work airgap and the magnetic-conductive ring; and the current-carrying coil of the rotor is connected reversely in series with the coil framework, and is positioned in the magnetic field of the work airgap. The utility model, which has simple integral structure and scientific and reasonable design, is a permanent magnet torquer with high stability, high linearity, high symmetry and low interference, and is particularly suitable to use in a gyroscope, an accelerometer, a torque test instrument and the like.

Description

Permanent magnet torquer

Technical field

The utility model belongs to instrument field, is suitable for inertial measurement component such as gyroscope, accelerometer and torgue measurement instrument etc., particularly a kind of high stable, high linearity, high symmetry and the low permanent magnet torquer that disturbs.

Background technology

Torquer is generally packaging structure, contains stator and rotor two parts, and its function is can produce moment between the stator and rotor, and the rotor relative stator is offset.The version of finishing the torquer of this function at present comprises: flat annular alternating current impression torquer, microsyn formula torquer, eddy current damping formula torquer, permanent magnet D.C. torque motor and permanent magnet torquer.The principle of work of the torquer of different structure and stability thereof, the linearity, symmetry and disturbance torque are inequality.Gyroscope, acceleration are taken into account high-precision force square measuring instrument: 1) high stability,＜5x10 ^-4/ ℃; 2) high linearity,＜0.5%; 3) high symmetry,＜1%; 4) low disturbance torque.At the restriction of this technical indicator and gyroscope, arrangements of accelerometers volume, environment etc., the torquer of suitable usefulness is a permanent magnet torquer, but material behavior and structure establishment are all had specific (special) requirements.

Summary of the invention

The purpose of this utility model provides a kind of high stable, high linearity, high symmetry and the low permanent magnet torquer that disturbs.

The purpose of this utility model is achieved through the following technical solutions:

A kind of permanent magnet torquer, comprise stator, rotor and magnetic guiding loop and compensating circuit, stator, rotor and magnetic guiding loop are coaxial, centering is installed, stator comprises permanent-magnet steel and stator magnetic ring, rotor comprises current-carrying coil and coil rack, it is characterized in that: the permanent-magnet steel surface polarity of described stator " N, S " intersection is distributed on the stator magnetic ring, and forms closed loop direct current magnetic loop through working gas gap, magnetic guiding loop; The current-carrying coil of rotor is connected also reversal connection on coil rack, and is in the working gas gap magnetic field.

And described compensating circuit is in the current-carrying coil resistance R _T, inductance L _TIn parallel one by resistance R on the branch road _W, capacitor C _WThe branch road of series connection.

Advantage of the present utility model and good effect are:

This permanent magnet torquer one-piece construction is simple, and design science is reasonable, is a kind of high stable, high linearity, high symmetry and the low permanent magnet torquer that disturbs, and is specially adapted to gyroscope, acceleration and takes into account in the torque detector etc.

Description of drawings

Fig. 1 is the utility model torquer three-dimensional structure diagram;

Fig. 2 is the front schematic view of Fig. 1 stator and magnetic guiding loop;

Fig. 3 is the perspective view of Fig. 1 rotor;

Fig. 4 is the utility model external compensation circuit theory diagrams.

Embodiment

The utility model is described in further detail below in conjunction with accompanying drawing, by specific embodiment.Following examples are descriptive, are not determinate, can not limit protection domain of the present utility model with this.

The permanent magnet torquer that the utility model is related can be divided into two kinds of forms during installation: a kind of is that current-carrying coil is a rotor, and permanent-magnet steel and magnetic guiding loop are stator; A kind of is that current-carrying coil is a stator, and permanent-magnet steel and magnetic guiding loop are rotor.Permanent-magnet steel and magnetic guiding loop are used for producing D.C. magnetic field; Current-carrying coil is in the D.C. magnetic field, makes the rotor relative stator produce moment after the energising, is offset.Embodiment of the present utility model adopts first kind of form.

A kind of permanent magnet torquer referring to Fig. 1, comprises stator 1, rotor 2 and magnetic guiding loop 3, and stator, rotor and magnetic guiding loop are coaxial, centering is installed.Stator comprises permanent-magnet steel 4 and stator magnetic ring 5, permanent-magnet steel surface polarity " N, S " intersection is distributed on the stator magnetic ring, (present embodiment is four examples very with the permanent-magnet steel of stator) forms closed loop direct current magnetic loop (seeing accompanying drawing 2) through working gas gap 6, magnetic guiding loop.Rotor comprises current-carrying coil 7 and coil rack 8 (see figure 3)s, and current-carrying coil is connected reversal connection on coil rack, and is in the working gas gap magnetic field.Produce moment behind the current-carrying coil galvanization, the rotor relative stator is deflected.Rotor requires material, and the iron content magnetic impurity is not in case spline is magnetized and influences moment characteristics, and rotor is adsorbed by stator and produces disturbance torque.The D.C. magnetic field center rotor current-carrying coil that stator and rotor centering installation requirement stator permanent-magnet steel produces is exactly permanent-magnet steel center and the axial limit of current-carrying coil centering from geometry.

According to the requirement of structural volume restriction and permanent magnet torquer constant multiplier, the permanent-magnet steel of stator can be divided into 2 utmost points, 4 utmost points, 6 utmost points, 8 utmost points again ... etc. structure.Number of pole-pairs is many more, and constant multiplier is big more, but the range of linearity scope of work reduces relatively; Just the circumferential width of permanent-magnet steel reduces relatively, and the residing magnetic field of current-carrying coil homogeneity range narrows down relatively, the linearity of meeting influence scale factor.The permanent magnet torquer output characteristics is:

M_{T} = \frac{1}{9810} (2 L_{a}) \cdot (2 P) \cdot W_{T} \cdot r \cdot B_{δ} \cdot I - - - (1)

The torquer constant multiplier is:

K_{T} = \frac{1}{9810} (2 L_{a}) (2 P) \cdot W_{T} \cdot r \cdot B_{δ} - - - (2)

In the formula: L _aThe effective length of-current-carrying coil in working gas gap;

The P-number of pole-pairs (with 2 very 1 pair, P=2,4 utmost points, P=3,6 utmost points ...);

R-current-carrying coil radius-of-curvature;

W _T-1 current-carrying coil number of turn;

B _δMagnetic induction density in the-working gas gap;

I-current-carrying coil electrical current.

From formula (1) as can be seen, number of pole-pairs P, coil turn W _T, magnetic induction density B _δBe directly proportional with moment with electric current I.For improving constant multiplier and stability, principle of design is usually: increase magnetic induction density B as much as possible _δWith current-carrying coil radius-of-curvature or raising number of pole-pairs, reduce coil turn and resistance as far as possible.For in limited volume range, reasonable in design, material behavior the best, moment performance maximum efficiency and stable, permanent magnetic material selects to have high energy product, high-coercive force and low remanent magnetism temperature coefficient.Permeability magnetic material will have high saturated magnetic induction and low-coercivity.The permanent magnetic material that can Gong select for use at present has: aluminium nickel cobalt, platinum cobalt, SmCo and neodymium iron boron.Aluminium nickel cobalt, platinum cobalt and SmCo remanent magnetism temperature coefficient 1～5x10 ^-4/ ℃.Neodymium iron boron 9～11x10 ^-4/ ℃.Aluminium nickel cobalt, platinum cobalt magnetic energy product＜10MGsOe, SmCo, neodymium iron boron magnetic energy product＞20MGsOe.Platinum cobalt, neodymium iron boron are than aluminium nickel cobalt, SmCo good processability, but neodymium iron boron easily gets rusty.The platinum cobalt costs an arm and a leg.Comprehensively above-mentioned, the SmCo good cost performance also is the material that extensively adopts at present.Aluminium nickel cobalt, platinum cobalt have also obtained application in the less demanding occasion of magnetic property.Aluminium nickel cobalt, platinum cobalt and SmCo have successively all been done testpieces, and performance all can reach the index request of gyroscope, accelerometer proposition.Consider the processing characteristics and the reliability requirement of product, finally in the gyroscope product, adopted platinum cobalt permanent magnetic material.Permeability magnetic material is alternative to be had: pure iron DT4, fe-Ni soft magnetic alloy 1J46,1J50,1J79,1J85, fe-Co-V soft magnetic alloy 1J22 and amorphous soft-magnetic alloy etc.Pure iron DT4 easily gets rusty, amorphous soft-magnetic alloy shapes the part difficulty, uses less in torquer.Fe-Ni soft magnetic alloy 1J79,1J85 saturation induction density＜0.75T, coercive force＜2.4A/m.1J46,1J50 saturation induction density＜1.5T, coercive force＜16A/m.Fe-Co-V soft magnetic alloy 1J22 saturation induction density＜2.4T, coercive force＜123A/m.Performance is fe-Ni soft magnetic alloy 1J46,1J50 preferably.Under the condition of certain structures restriction, require big constant multiplier and the magnetic guiding loop volume can not be enough big, use fe-Co-V soft magnetic alloy 1J22, utilize its high saturated magnetic induction.In the permanent magnet torquer of development, fe-Ni soft magnetic alloy 1J46,1J50, fe-Co-V soft magnetic alloy 1J22 has obtained application, has reached expectation index.

The function of rotor is current-carrying coil energising, and is in and produces moment in the magnetic field.But current-carrying coil is thin arc structure (see figure 3), itself can not location-independent in magnetic field, need be located to satisfy the requirement of current-carrying coil and permanent-magnet steel centering by coil rack.Coil rack requires to nonferromugnetic material, is thin-walled parts because of the rotor skeleton again, requires dimensionally stable, so material is selected to have: insulating material and conductive material aluminium, titanium alloys etc. such as alundum (Al pottery, devitrified glass, polysulfones, polyphenylene sulfide.But the thermal expansion factor of rotor framework material as far as possible with the thermal expansion factor coupling of mating parts material.Have if the logical electric current of current-carrying coil is pulse current (as adopting the binary Pulse Width Modulation Control With), framework material should not adopt conductive material aluminium, titanium alloy etc., easily forms the vortes interference changes of magnetic field again.Using at present maximum in moment is alundum (Al pottery, devitrified glass and aluminium.These three kinds of materials have all been done testpieces, satisfy the torquer index request.In use can adopt according to different requirements.

Fig. 4 is the compensating circuit schematic diagram, R _T, L _TBe current-carrying coil resistance and inductance, and also have distributed capacitance C _TWhen current-carrying coil was promoted blood circulation towards electric current, the level of pulse current and polarity can cause undesirable transient process.Be that pulse current is at R _T, L _TCircuit in the inertia of rise and fall appears.This inertia can influence the linearity of torquer output.For reducing this inertia or transient process, will compensate the torquer coil.This compensation comes down to a suitable resistance R _WAnd capacitor C _WResistance R with the torquer current-carrying coil _T, inductance L _TWith distributed capacitance C _TCoupling forms a pure resistance circuit, can make the transient process minimum of torquer like this.

From the compensating circuit schematic diagram of Fig. 4, current-carrying coil resistance R _T, inductance L _TBranch road is in the process resistance R _W, capacitor C _WBehind the branch road fine compensation, the current-carrying coil resistance R _T, inductance L _TThe unidirectional average current that branch road obtains, though the unidirectional average current waveform that produces on pure resistance with pulse current is different, the static flow valuve is equivalence fully.That is to say, by way of compensation the resistance R of usefulness _W, capacitor C _WBranch road only improves the front and back of electric current along waveform, and the unidirectional average current that can paired pulses produce forms the one-way distributing effect.

Claims

1. permanent magnet torquer, comprise stator, rotor and magnetic guiding loop and compensating circuit, stator, rotor and magnetic guiding loop are coaxial, centering is installed, stator comprises permanent-magnet steel and stator magnetic ring, rotor comprises current-carrying coil and coil rack, it is characterized in that: the permanent-magnet steel surface polarity of described stator " N, S " intersection is distributed on the stator magnetic ring, and forms closed loop direct current magnetic loop through working gas gap, magnetic guiding loop; The current-carrying coil of rotor is connected also reversal connection on coil rack, and is in the working gas gap magnetic field.

2. permanent magnet torquer according to claim 1 is characterized in that: described compensating circuit is in the current-carrying coil resistance R _T, inductance L _TIn parallel one by resistance R on the branch road _W, capacitor C _WThe branch road of series connection.