CN114935719A

CN114935719A - Magnetic leakage prevention and high-damping performance test system for magnetostrictive actuator

Info

Publication number: CN114935719A
Application number: CN202210460601.5A
Authority: CN
Inventors: 白鸿柏; 黄烨阳; 吴乙万; 娄艺方
Original assignee: Fuzhou University
Current assignee: Fuzhou University
Priority date: 2022-04-28
Filing date: 2022-04-28
Publication date: 2022-08-23
Anticipated expiration: 2042-04-28

Abstract

The invention provides a magnetic leakage prevention and high-damping performance test system for a magnetostrictive actuator, which comprises a magnetostrictive actuator system, and a sensing system, an information acquisition control system, a power supply system and a temperature control system which are connected with the magnetostrictive actuator system; the magnetostrictive actuator system comprises a prestress applying mechanism formed by a metal rubber piece and a pretightening bolt (2), a magnetostrictive rod (16), a magnetic circuit system and a magnetostrictive actuator with a coil framework arranged inside; the metal rubber piece comprises annular metal rubber (3) arranged between the ejector rod protruding part and the pre-tightening bolt and between the ejector rod protruding part and the shaft sleeve, the pre-tightening bolt applies pre-stress to the magnetostrictive rod, and the annular metal rubber absorbs high-frequency energy excited by the outside; the prestress applying mechanism adjusts the damping and rigidity characteristics of the prestress applying mechanism by adjusting the preparation process of the metal rubber part; the invention has the characteristics of magnetic leakage prevention and high damping, and an active temperature control system is arranged in the invention.

Description

Magnetic leakage prevention and high-damping performance test system for magnetostrictive actuator

Technical Field

The invention relates to the technical field of test equipment, in particular to a magnetic leakage prevention and high damping performance test system for a magnetostrictive actuator.

Background

When the magnetostrictive actuator is applied to vibration active control, the magnetostrictive actuator is in contact with a vibration source, and the vibration of the vibration source is counteracted by driving the magnetostrictive rod to generate vibration with the same frequency as the vibration source and the opposite amplitude, so that the aim of eliminating and controlling the vibration is fulfilled. However, the magnetostrictive actuator is usually used for controlling the medium and low frequency vibration because the magnetostrictive material rod has the characteristics of large rigidity and difficult control and driving in high frequency vibration. The traditional magnetostrictive actuator generally adopts a spring as a prestress applying mechanism and has the characteristic of high rigidity of a magnetostrictive rod, so that the traditional magnetostrictive actuator is structurally undamped and does not have the capacity of dissipating external high-frequency excitation.

The existing magnetostrictive performance test system does not consider the problems of recovery and measurement of magnetic flux leakage of a coil of a magnetostrictive actuator, and leakage of a magnetic field can cause that a precise sensor and a matched test device in the test system cannot normally operate.

The existing magnetostrictive performance testing system does not have an active temperature adjusting function and can not carry out active temperature adjustment on the magnetostrictive performance testing system according to the heating of the coil. Because the output of the magnetostrictive material rod belongs to the micron level, the coil driving the magnetostrictive material rod can generate serious heating after large current is introduced. The heat generated by the coil is conducted to the magnetostrictive material rod to generate the influences of thermal expansion, magnetic performance change of the magnetostrictive material rod and the like. The displacement output measurement accuracy for the magnetostrictive material rod is seriously affected.

Disclosure of Invention

The invention provides a performance test system for a magnetic-leakage-proof and high-damping magnetostrictive actuator, which has the characteristics of magnetic leakage prevention and high damping, and an active temperature control system is arranged in the system, so that the performance of a magnetostrictive rod in different temperature environments can be tested.

A magnetic leakage prevention and high damping performance test system for a magnetostrictive actuator comprises a magnetostrictive actuator system, and a sensing system, an information acquisition control system, a power supply system and a temperature control system which are connected with the magnetostrictive actuator system; the magnetostrictive actuator system comprises a prestress applying mechanism formed by a metal rubber piece and a pre-tightening bolt (2), a magnetostrictive rod (16), a magnetic circuit system and a magnetostrictive actuator supported by a coil framework inside;

the upper part of a mandril (1) of the magnetostrictive actuator is provided with a bulge part positioned between a pre-tightening bolt and a shaft sleeve (7), and a base (24) is fixedly connected with a shell (15) of the actuator system through a fastener; the metal rubber part comprises annular metal rubber (3) arranged between a mandril boss and a pre-tightening bolt and between the mandril boss and a shaft sleeve, the pre-tightening bolt applies pre-stress to the magnetostrictive rod, and the annular metal rubber absorbs high-frequency energy excited by the outside; the prestress applying mechanism adjusts the damping and rigidity characteristics of the prestress applying mechanism by adjusting the preparation process of the metal rubber piece.

The ejector rod receives external excitation and then performs reciprocating motion in the axis direction; when the ejector rod (1) moves downwards, the metal rubber (3) clamped between the boss of the ejector rod and the shaft sleeve bears part of external load and consumes part of impact energy through self damping; when the ejector rod moves upwards along the axis, the metal rubber between the pre-tightening bolt (2) and the boss of the ejector rod bears load and consumes impact energy in the axis direction.

The external excitation is applied by an electromagnetic field generated by an excitation coil (17) and a bias coil (18) at the coil skeleton; the coil framework is arranged between the shaft sleeve (7) and the base of the magnetostrictive actuator.

The coil framework (12) is arranged on a magnetostrictive actuator base, the upper end and the lower end of the coil framework are round tables, and rectangular coil slots (12-1) and sensor slots (12-2) are arranged at the round tables at the lower end;

an upper magnetic conduction block (11), a magnetostrictive rod and a lower magnetic conduction block (19) are arranged in the tubular cavity in the center of the coil framework; an exciting coil (17) is wound on the inner side of the coil framework (12), and a bias coil (18) is wound outside the exciting coil (17); the coil wire is led out through a coil wire slot (12-1), an inner magnetic conduction wire rack hole (13-1), a middle magnetic conduction wire rack hole (14-1) and an outer shell wire hole (15-1);

after the hollow cylindrical excitation coil (17) and the bias coil (18) are electrified, a magnetic field is generated in the direction of the central axis of the coils, and the magnetic induction lines of the magnetic field circulate along a magnetic conduction loop formed by the magnetostrictive rod (16), the upper magnetic conduction block (11), the inner magnetic conduction end cover (9), the inner magnetic conduction frame (13), the inner magnetic conduction base (21) and the lower magnetic conduction block (19);

the test system also comprises a magnetic flux leakage measuring mechanism at the coil framework; the magnetic flux leakage measuring mechanism forms a magnetic conduction loop by a magnetostrictive rod, an upper magnetic conduction block, a lower magnetic conduction block, an inner magnetic conduction end cover (9), an inner magnetic conduction frame (13) and an inner magnetic conduction base (21), and forms a magnetic flux leakage recovery loop by a middle magnetic conduction end cover (6), a middle magnetic conduction frame (14) and a middle magnetic conduction base (22); a magnetism isolating end cover (8) is arranged between the inner magnetic end cover and the middle magnetic end cover; the inner magnetic conduction base is connected with the middle magnetic conduction base, so that the magnetic conduction loop is separated from the magnetic flux leakage recovery magnetic circuit, and the magnetic flux leakage recovery magnetic circuit conducts the magnetic flux leakage back to the magnetic conduction loop when electromagnetic field magnetic flux leakage generated by the excitation coil (17) and the bias coil (18) is recovered;

the middle-layer magnetic conduction base (22) separates the inner magnetic conduction frame (13) from the middle magnetic conduction frame (14) by a circular boss, and the inner magnetic conduction end cover (9) and the middle-layer magnetic conduction end cover (6) are separated by the magnetic isolation end cover (8), so that a magnetic induction line circulating in the magnetic conduction loop cannot be communicated with the magnetic leakage recovery loop;

the middle-layer magnetic conduction end cover (6), the middle-layer magnetic conduction frame (14) and the middle-layer magnetic conduction base (22) form a magnetic flux leakage recovery loop arranged on the outer layer of the magnetic conduction loop and used for absorbing leaked magnetic induction lines again; the leaked magnetic induction lines return to the magnetic conduction loop from the middle magnetic conduction base (22) and the inner magnetic conduction layer base (21) to complete magnetic flux leakage recovery;

the measuring system measures the external magnetic flux leakage of the magnetostrictive actuator through a teslameter, and uses a magnetic flux leakage recovery loop to ensure the uniformity of the internal magnetic field of the magnetostrictive actuator and increase the utilization rate of the magnetic field, and simultaneously reduces the interference of the internal magnetic field leakage on an eddy current displacement sensor in a sensing system;

the teslameter is connected with a second Hall probe arranged on the Hall probe bracket (27) to measure the leakage quantity of a magnetic field generated by the exciting coil (17) and the bias coil (18) outside the shell (15); the Hall probe bracket (27) is fixed on the flange threaded hole (24-2) of the actuator base through threaded connection.

The sensing system further comprises a first patch temperature sensor (25-1) adhered to the surface of the magnetostrictive rod (16), a strain gauge (26) used for collecting strain information of the magnetostrictive rod, a first Hall probe (20-1) positioned in the lower magnetic conduction block slot (19-1) and used for measuring the axial magnetic field intensity of the magnetostrictive rod, a second patch temperature sensor (25-2) adhered between the exciting coil (17) and the bias coil (18), and a dynamic force sensor (23) arranged in a cylindrical groove in the center of the actuator base (24); the ejector rod (1), the upper magnetic conduction block (11), the magnetostrictive rod (16), the lower magnetic conduction block (19), the inner magnetic conduction base (21), the middle magnetic conduction base (22) and the dynamic force sensor (23) are positioned on the same axis; the dynamic force sensor (23) is clamped in a gap between the middle magnetic conduction base (22) and the actuator base (24);

when external load is input from the ejector rod (1), the external load and the prestress are transmitted to the dynamic force sensor (23) along the axial direction, so that the force measurement is realized; the dynamic force sensor wire is led out of an information acquisition control system of an upper computer through an actuator base wire slot (24-1) and a shell wire hole (15-2);

the eddy current displacement sensor (28) is fixed on the end cover (4) by using threads, when a coil generates a magnetic field to excite the magnetostrictive rod (16) to output displacement, the displacement is transmitted to the ejector rod (1) through the upper magnetic conduction block (11), and the eddy current displacement sensor (28) obtains the displacement output of the actuator by measuring the displacement of the ejector rod (1) in the axial direction; when a load is applied from the outside, the sensing system measures the deformation of the inner part of the magnetostrictive actuator caused by the external load through an eddy current displacement sensor (28).

The temperature control system comprises a cooling water channel arranged in the coil framework, a water pump of the cooling water channel is arranged in an external water tank, and cooling water of a pipeline in the cooling water channel is driven to circularly flow;

the temperature control system also comprises a constant temperature rod, a cold air exhaust and a fan; the constant temperature rod is arranged in the water tank and used for heating cooling water, and the cold row and the fan are used for cooling the cooling water;

the temperature control system also comprises a first temperature sensor and a second temperature sensor which are arranged in the magnetostrictive actuator, and a water tank temperature sensor for detecting the temperature of cooling water in the water tank; the first temperature sensor, the second temperature sensor and the water tank temperature sensor are all connected with the single chip microcomputer;

the single chip microcomputer calls information of a first temperature sensor, a second temperature sensor and a water tank temperature sensor in the magnetostrictive actuator through a preset program, automatically adjusts the temperature of the fan and the temperature of the thermostatic bar in a voltage adjusting mode, and simultaneously sends the information of the temperature of the water tank and the rotating speed of the fan to an upper computer for recording;

when the temperature measured by the first temperature sensor and the second temperature sensor is higher than the preset temperature in the program, the temperature control system is adjusted to a cooling state, the constant temperature rod is closed, and the cold air is discharged and the fan is used for transferring the heat in the cooling water to the air, so that the effect of cooling is achieved;

when the temperature measured by the first temperature sensor and the second temperature sensor is lower than the preset temperature in the program, the temperature control system is adjusted to a heating state, the constant temperature rod is started to heat the cooling water, and the fan is turned off, so that the effect of temperature rise is achieved;

when the temperature measured by any one of the first temperature sensor and the second temperature sensor exceeds 80 ℃, the singlechip issues an overheating alarm to the upper computer, and the upper computer automatically returns to zero to enable the excitation coil and the bias coil to stop introducing current according to a signal transmitted by the signal generator;

when the temperature measured by the water tank temperature sensor is lower than 0 ℃, the singlechip issues a low-temperature warning to the upper computer to prompt a user to check whether the water tank is normal and select whether to turn on the constant temperature rod for heating so as to eliminate the abnormal state of freezing of cooling water;

when the temperature control system determines the preset temperature in the actual use, the temperature control system automatically selects a cooling state or a heating state around the preset temperature, and the two states are mutually switched to achieve the purpose of keeping the temperature of the cooling water constant;

in the magnetostrictive actuator, a shell (15) is fixedly connected with an end cover (4) through a bolt, a circular pressing ring (5) is arranged on the inner side of the end cover (4), a pre-tightening bolt (2) is connected with the end cover (4) through a thread, and an ejector rod (1) is arranged in a groove of an upper magnetic conduction block (11). A bolt hole (24-4) in the actuator base (24) is used for fixing the magnetostrictive actuator on the T-shaped groove platform;

the actuator base (24) is in a disc shape and is fixedly connected with the shell (15) through a sunk screw, a dynamic force sensor lead is led out through an actuator base wire groove (24-1) and a shell wire hole (15-2), the shell (15) is fixedly connected with the end cover (4) through a bolt, the annular pressing ring (5) is arranged on the inner side of the end cover (4), the pre-tightening bolt (2) is connected with the end cover (4) through a thread, and the ejector rod (1) is arranged in a groove of the upper magnetic conduction block (11); a bolt hole (24-4) in the actuator base (24) is used for fixing the magnetostrictive actuator on the T-shaped groove platform;

the cooling water channel is a hollow cylindrical water cooling channel outside the central cavity of the coil skeleton, and the water cooling channel comprises a stainless steel quick-screwing standard part; the upper part and the lower part of the cylindrical water cooling channel are respectively communicated with an upper linear cooling channel (12-3) and a lower linear cooling channel (12-4), and the two linear cooling channels are connected with a water cooling head (10) by using threads; the water-cooling head at the upper end passes through the upper through hole (14-3) of the middle magnetic conduction frame and the upper through hole (15-4) of the shell, and the water-cooling head at the lower end passes through the wire hole (14-1) of the middle magnetic conduction frame and the lower wire hole (15-1) of the shell.

The exciting coil and the bias coil are coated with silicone grease when the coils are wound, and the silicone grease fills gaps around the wires to increase the heat transfer efficiency; the magnetic conduction material of the magnetic flux leakage measuring mechanism adopts electrician pure iron; the material of the magnetic isolation end cover is H62 brass material.

In the magnetic field design of the exciting coil and the bias coil, a field intensity range with the maximum magnetostriction rate variation of the magnetostrictive rod is selected as a working interval, in the interval, the magnetostriction variation of the magnetostrictive rod is obvious, and the field intensity and the magnetostriction rate are approximate to a linear relation.

The magnetic fields of the exciting coil and the bias coil depend on the ampere turns and the geometric size of the coil; the actuator is characterized in that a main coil inside the actuator and all parts of a coil framework are provided, a bias coil is embedded in the outer layer of an excitation coil, the excitation coil is arranged inside the main coil, a magnetostrictive rod is arranged in the center of the framework, and the size of the main coil used for designing the magnetic field intensity of any point on a shaft line is calculated in advance;

let P be any point on the axis of the bus ring, X denote the position of P in the axial direction, d _i The inner diameter of the framework is used for installing a magnetostrictive rod. e is the total coil overall thickness, R1 is the AC coil inner diameter, R3 is the AC coil outer diameter, R2 is the bias coil outer diameter, L _coil For the coil length, the magnetic induction at point P is:

wherein, mu ₀ Is air permeability, n is the number of turns of wire per unit length, I is the current intensity in the wire, theta ₁ ，θ ₂ Is the included angle between the point P and the two ends of the coil. Take a coil of radius r and thickness dr for each layer. The number of turns per layer is:

the number of coil turns n per unit length is:

θ ₁ ，θ ₂ the geometrical relationship of the two angles is:

the magnetic induction intensity generated by each layer of coil is as follows:

the magnetic induction intensity B of any point P can be obtained as follows:

magnetic field intensity H _P Comprises the following steps:

the value range of the coil length is 1.05-1.1 times of the length of a magnetostrictive rod (GMM); the coil height is denoted L _coil ：

L _coil ＝(1.05～1.1)L _GMM A formula is ten;

determination of the magnetic field strength H _P And the total ampere turns NI of the coils, and further distributing the proportion of the exciting coils in the coils to the total coils after the total coil size R2 is designed in a substituting manner.

In an alternating current magnetic field and bias magnetic field experiment, according to the frequency doubling principle of a magnetostrictive rod, presetting currents I with the same magnitude applied on an excitation coil and a bias coil; the exciting coil and the bias coil are separated, the distances between the two groups of coils and the magnetostrictive rod are unequal, the field intensity difference generated by the distances is made up by designing the coils with different sizes, and the specific method comprises the following steps:

after the current relationship between the two coils is determined, when the two groups of coils need to generate equal field intensity on the axis, the size relationship of the two groups of coils is determined according to a formula, and the number of turns of the exciting coil is set to be N _{Movable part} Excitation magnetic field intensity of H _{Movable part} Bias coil turns number N _Quiet Bias magnetic field intensity H _Quiet If the two relations are: h _{Movable part} ≤H _Quiet Substituting it into the formula can result in:

wherein the content of the first and second substances,

N _{movable part} ＝(R ₃ -R ₁ )×n ₂ ×L _coil ×n ₁ A formula twelve;

N _quiet ＝(R ₂ -R ₃ )×n ₂ ×L _coil ×n ₁ A formula thirteen;

the formula is derived:

the invention has the advantages that:

1. the magnetostrictive actuator has damping characteristics, vibration is passively controlled through the metal rubber, part of high-frequency vibration input from the outside is eliminated, and the active control of low-frequency vibration in the magnetostrictive rod is matched, so that the vibration reduction frequency range is widened.

2. The magnetostrictive actuator has better magnetic sealing property.

3. The magnetostrictive actuator has better heat dissipation characteristic.

4. The magnetostrictive performance testing system can measure the magnetic flux leakage of the magnetostrictive actuator.

5. The magnetostrictive performance testing system has an active temperature control function.

The invention designs a magnetic leakage prevention and high damping magnetostrictive actuator, provides an experimental device for testing the basic characteristics of magnetostrictive materials, the frequency response characteristics of the magnetostrictive actuator, magnetic leakage and other properties, and can provide reference for the application and theoretical research of the magnetostrictive actuator.

Drawings

The invention is described in further detail below with reference to the following figures and detailed description:

FIG. 1 is a schematic diagram of the dimensions of a coil and a coil bobbin;

fig. 2 to 7 are schematic views of external structures of a magnetostrictive actuator, wherein fig. 6 is a top view, and fig. 7 is a bottom view;

FIGS. 8-9 are schematic internal cross-sectional views;

FIG. 10 is a schematic diagram of a magnetostrictive actuator performance testing system;

FIG. 11 is a schematic diagram of a bobbin structure;

in the figure: 1-a top rod; 2-pre-tightening the bolt; 3-a metal rubber; 4-end cover; 5-pressing a ring; 6-middle magnetic end cap; 7-shaft sleeve; 8-magnetic isolation end cover; 9-inner magnetic end cap;

10-1, a first water-cooling joint; 10-2, a second water-cooling joint; 11-upper magnetic conduction block; 12-a coil former; 12-1 coil wire chase; 12-2, a sensor wire slot; 12-3, arranging a straight cooling channel; 12-4, a lower straight cooling channel; 13-inner magnetic conduction frame; 13-1, an inner magnetic conduction frame wire hole; 14-an intermediate magnetic conduction frame; 14-1, a middle magnetic conduction rack hole; 15-a housing; 15-1, a housing wire hole; 15-2, quickly screwing holes on the shell; 16-a magnetostrictive rod; 17-an excitation coil; 18-a bias coil; 19-lower magnetic conduction block; 19-1, a lower magnetic conduction block through groove;

20-1, a first hall probe; 20-2, a second Hall probe; 21-inner magnetic conduction base; 22-middle magnetic base; 23-a dynamic force sensor; 24-an actuator base; 24-1, a dynamic force sensor wire slot; 24-2, base flange threaded holes; 25-1, a first patch temperature sensor; 25-2, a second patch temperature sensor; 26-a strain gauge; 27-teslameter holder; 28-eddy current displacement sensor.

Detailed Description

As shown in the figure, the magnetic leakage prevention and high damping performance test system for the magnetostrictive actuator comprises a magnetostrictive actuator system, and a sensing system, an information acquisition control system, a power supply system and a temperature control system which are connected with the magnetostrictive actuator system; the magnetostrictive actuator system comprises a prestress applying mechanism formed by a metal rubber piece and a pretightening bolt 2, a magnetostrictive rod 16, a magnetic circuit system and a magnetostrictive actuator supported by a coil framework inside;

the upper part of the ejector rod 1 of the magnetostrictive actuator is provided with a convex part between the pre-tightening bolt and the shaft sleeve 7, and the base 24 is fixedly connected with the shell 15 of the actuator system through a fastener; the metal rubber piece comprises annular metal rubber 3 arranged between a mandril boss and a pre-tightening bolt and between the mandril boss and a shaft sleeve, the pre-tightening bolt applies pre-stress to the magnetostrictive rod, and the annular metal rubber absorbs high-frequency energy excited by the outside; the prestress applying mechanism adjusts the damping and rigidity characteristics of the prestress applying mechanism by adjusting the preparation process of the metal rubber piece.

The ejector rod receives external excitation and then performs reciprocating motion in the axis direction; when the ejector rod 1 moves downwards, the metal rubber 3 clamped between the boss of the ejector rod and the shaft sleeve bears part of external load and consumes part of impact energy through self damping; when the ejector rod moves upwards along the axis, the metal rubber between the pre-tightening bolt 2 and the boss of the ejector rod bears load and consumes impact energy in the axis direction.

The external excitation is applied by an electromagnetic field generated by an excitation coil 17 and a bias coil 18 at the bobbin; the coil framework is arranged between the shaft sleeve 7 and the base of the magnetostrictive actuator.

The coil framework 12 is arranged on a magnetostrictive actuator base, the upper end and the lower end of the coil framework are round tables, and rectangular coil slots 12-1 and sensor slots 12-2 are arranged at the round tables at the lower end;

an upper magnetic conduction block 11, a magnetostrictive rod and a lower magnetic conduction block 19 are arranged in a tubular cavity in the center of the coil framework; the exciting coil 17 is wound on the inner side of the coil framework 12, and the bias coil 18 is wound outside the exciting coil 17; the coil wire is led out through the coil wire slot 12-1, the inner magnetic conduction wire rack hole 13-1, the middle magnetic conduction wire rack hole 14-1 and the shell wire hole 15-1;

after the hollow cylindrical excitation coil 17 and the bias coil 18 are electrified, a magnetic field is generated in the direction of the central axis of the coils, and magnetic induction lines of the magnetic field circulate along a magnetic conduction loop formed by the magnetostrictive rod 16, the upper magnetic conduction block 11, the inner magnetic conduction end cover 9, the inner magnetic conduction frame 13, the inner magnetic conduction base 21 and the lower magnetic conduction block 19;

the test system also comprises a magnetic flux leakage measuring mechanism at the coil framework; the magnetic leakage measuring mechanism forms a magnetic conduction loop by a magnetostrictive rod, an upper magnetic conduction block, a lower magnetic conduction block, an inner magnetic conduction end cover 9, an inner magnetic conduction frame 13 and an inner magnetic conduction base 21, and forms a magnetic leakage recovery loop by a middle magnetic conduction end cover 6, a middle magnetic conduction frame 14 and a middle magnetic conduction base 22; a magnetism isolating end cover 8 is arranged between the inner magnetism conducting end cover and the middle magnetism conducting end cover;

the inner magnetic conduction base is connected with the middle magnetic conduction base, so that the magnetic conduction loop is separated from the magnetic flux leakage recovery magnetic circuit, and the magnetic flux leakage recovery magnetic circuit conducts the magnetic flux leakage back to the magnetic conduction loop when electromagnetic field magnetic flux leakage generated by the excitation coil 17 and the bias coil 18 is recovered;

the middle-layer magnetic conduction base 22 separates the inner magnetic conduction frame 13 from the middle magnetic conduction frame 14 by a circular boss, and the magnetic isolation end cover 8 separates the inner magnetic conduction end cover 9 from the middle-layer magnetic conduction end cover 6, so that a magnetic induction line circulating in a magnetic conduction loop cannot be communicated with a magnetic leakage recovery loop;

the middle-layer magnetic conduction end cover 6, the middle magnetic conduction frame 14 and the middle-layer magnetic conduction base 22 form a magnetic leakage recovery loop arranged on the outer layer of the magnetic conduction loop and used for absorbing leaked magnetic induction lines again; the leaked magnetic induction lines return to the magnetic conduction loop from the middle magnetic conduction base 22 and the inner magnetic conduction base 21 to complete magnetic flux leakage recovery;

the teslameter is connected with a second Hall probe arranged on the Hall probe bracket 27 to measure the leakage quantity of the magnetic field generated by the exciting coil 17 and the bias coil 18 outside the shell 15; the Hall probe bracket 27 is fixed on the threaded hole 24-2 of the actuator base flange through threaded connection.

The sensing system also comprises a first patch temperature sensor 25-1 adhered to the surface of the magnetostrictive rod 16, a strain gauge 26 used for collecting strain information of the magnetostrictive rod, a first Hall probe 20-1 positioned in the lower magnetic conduction block slot 19-1 and used for measuring the axial magnetic field intensity of the magnetostrictive rod, a second patch temperature sensor 25-2 adhered between the exciting coil 17 and the bias coil 18 and a dynamic force sensor 23 arranged in a cylindrical groove at the center of the actuator base 24; the ejector rod 1, the upper magnetic conduction block 11, the magnetostrictive rod 16, the lower magnetic conduction block 19, the inner magnetic conduction base 21, the middle magnetic conduction base 22 and the dynamic force sensor 23 are positioned on the same axis; the dynamic force sensor 23 is clamped in a gap between the middle magnetic conduction base 22 and the actuator base 24;

when external load is input from the ejector rod 1, the external load and the prestress are transmitted to the dynamic force sensor 23 along the axial direction, so that the force measurement is realized; the dynamic force sensor lead is led out to an information acquisition control system of an upper computer through an actuator base wire slot 24-1 and a shell wire hole 15-2;

the electric eddy current displacement sensor 28 is fixed on the end cover 4 by using threads, when the coil generates a magnetic field to excite the magnetostrictive rod 16 to output displacement, the displacement is transmitted to the ejector rod 1 through the upper magnetic conduction block 11, and the electric eddy current displacement sensor 28 obtains the displacement output of the actuator by measuring the displacement of the ejector rod 1 in the axial direction; when a load is applied from the outside, the sensing system measures the deformation of the inner part of the magnetostrictive actuator caused by the external load through the eddy current displacement sensor 28.

the temperature control system also comprises a constant temperature rod, a cold air exhaust and a fan; the constant temperature rod is arranged in the water tank and used for heating cooling water, and the cold discharge and the fan are used for cooling the cooling water;

when the temperature control system determines the preset temperature in the actual use, the temperature control system automatically selects a cooling state or a heating state around the preset temperature, and the two states are mutually switched to achieve the purpose of keeping the cooling water at constant temperature;

in the magnetostrictive actuator, a shell 15 is fixedly connected with an end cover 4 through a bolt, a circular pressing ring 5 is arranged on the inner side of the end cover 4, a pre-tightening bolt 2 is connected with the end cover 4 through a thread, and an ejector rod 1 is arranged in a groove of an upper magnetic conduction block 11. A bolt hole 24-4 in the actuator base 24 is used for fixing the magnetostrictive actuator on the T-shaped groove platform;

the actuator base 24 is disc-shaped and is fixedly connected with the shell 15 through a sunk screw, a dynamic force sensor wire is led out through an actuator base wire groove 24-1 and a shell wire hole 15-2, the shell 15 is fixedly connected with the end cover 4 through a bolt, the annular pressing ring 5 is arranged on the inner side of the end cover 4, the pre-tightening bolt 2 is connected with the end cover 4 through a thread, and the ejector rod 1 is arranged in a groove of the upper magnetic conduction block 11; a bolt hole 24-4 in the actuator base 24 is used for fixing the magnetostrictive actuator on the T-shaped groove platform;

the cooling water channel is a hollow cylindrical water cooling channel outside the central cavity of the coil skeleton, and the water cooling channel comprises a stainless steel quick-screwing standard part; the upper part and the lower part of the cylindrical water cooling channel are respectively communicated with an upper linear cooling channel 12-3 and a lower linear cooling channel 12-4, and the two linear cooling channels are connected with a water cooling head 10 by threads; the water-cooling head at the upper end passes through the upper through hole 14-3 of the middle magnetic conduction frame and the upper through hole 15-4 of the shell, and the water-cooling head at the lower end passes through the wire hole 14-1 of the middle magnetic conduction frame and the lower wire hole 15-1 of the shell.

The exciting coil and the bias coil are coated with silicone grease when the coils are wound, and the silicone grease fills gaps around the conducting wires to increase heat transfer efficiency; the magnetic conduction material of the magnetic flux leakage measuring mechanism is made of electrician pure iron; the material of the magnetic isolation end cover is H62 brass material.

The magnetic fields of the exciting coil and the bias coil depend on the ampere turns and the geometric size of the coil; the actuator comprises a main coil inside the actuator and all parts of a coil framework, a bias coil is embedded in the outer layer of an excitation coil, the excitation coil is placed inside, a magnetostrictive rod is arranged in the center of the framework, and the size of the main coil used for designing the magnetic field intensity of any point on a shaft line is calculated in advance;

wherein, mu ₀ Is air permeability and n is unit lengthThe number of turns of the wire, I is the current intensity in the wire, theta ₁ ，θ ₂ Is the included angle between the point P and the two ends of the coil. Take a coil of radius r and thickness dr for each layer. The number of turns per layer is:

the number of coil turns n per unit length is:

θ ₁ ，θ ₂ the geometrical relationship of the two angles is:

the magnetic induction intensity generated by each layer of coil is as follows:

the magnetic induction intensity B of any point P can be obtained as follows:

magnetic field intensity H _P Comprises the following steps:

L _coil ＝(1.05～1.1)L _GMM A formula ten;

wherein the content of the first and second substances,

N _{movable part} ＝(R ₃ -R ₁ )×n ₂ ×L _coil ×n ₁ A formula twelve;

N _quiet ＝(R ₂ -R ₃ )×n ₂ ×L _coil ×n ₁ A formula thirteen;

the formula is derived:

example 1:

in this example, in the sensing system of the test system, the signal output end of the strain gauge (26) is connected with the signal input end of a strain gauge through an electrical bridge, the signal output end of the strain gauge is connected with the signal input end of the data acquisition card, the acquired strain information of the magnetostrictive rod is sent to the data acquisition card for processing, and the processed strain information is transmitted to an upper computer through the data acquisition card for recording. The resistance value of the strain gauge is 120 ohms, the room temperature strain limit is 2000um/m, and the suitable temperature is-30-70 ℃.

The output ends of the first Hall probe (20-1) and the second Hall probe (20-2) are connected with the input end of the teslameter, when the Hall sensor receives a magnetic field signal, the magnetic field information is transmitted to the teslameter for processing, and then transmitted to the data acquisition card to be sent to the upper computer for recording. The first Hall sensor (20-1) is used for measuring the axial magnetic field intensity of the magnetostrictive rod, and the second Hall sensor (20-2) is used for measuring the leakage amount of the external magnetic field of the magnetostrictive actuator.

The maximum measuring range of the tesla meter is 2000mT, the minimum resolution is 1 muT, the bandwidth of the alternating current magnetic field is measured to be 0-5 kHz, the measurement accuracy of the alternating current magnetic field is +/-2% RD, and the measurement accuracy of the direct current magnetic field is

+ (0.5% RD + 100. mu.T), where RD is the reading value.

And the dynamic force sensor transmits the acquired pressure signals to the upper computer through the force transmitter by a data acquisition card, and the upper computer is used for recording force information. The dynamic force sensor has the measuring range of 5kN, the working temperature of-40-150 ℃, the sensitivity of 3.05pC/N and the repeatability of less than or equal to 1 percent.

The first temperature sensor and the second temperature sensor are respectively adhered to the outer surfaces of the magnetostrictive rod and the exciting coil and are used for measuring the internal temperature of the magnetostrictive actuator and controlling the opening of the temperature control system, and the first temperature sensor and the second temperature sensor are matched with the water tank temperature sensor, the constant temperature rod, the water pump, the cold bar and the fan to ensure the safe operation of the system. The temperature sensor is connected with the single chip microcomputer, temperature information is transmitted to the single chip microcomputer to be processed, and the single chip microcomputer uploads the information to an upper computer to be monitored and recorded. The measuring range of the first temperature sensor and the second temperature sensor is 0-200 ℃, and the temperature measuring precision is 0.5-1 ℃. The measuring range of the water tank temperature sensor is-55-125 ℃.

The eddy current sensor is arranged between the end cover and the ejector rod, is connected with the displacement transmitter, and sends collected ejector rod displacement signals to the upper computer through the data acquisition card for monitoring and recording. The measuring range of the eddy current sensor is 1mm, the linear error (% FS) is less than or equal to +/-0.25, the resolution is 0.05um, and the frequency response is 0-10 kHz.

The information acquisition control system of the test system mainly comprises an upper computer, a single chip microcomputer and a data acquisition card. The single chip microcomputer and the data acquisition card are respectively connected with the upper computer, the single chip microcomputer is responsible for receiving information sent by the sensor outputting the analog signals and converting the analog signals into digital signals, the data acquisition card is responsible for receiving data information sent back by the sensor supporting the RS232/485 transmission protocol, and the data acquisition card can both output control signals sent by the upper computer to control the sensor connected with the image of the single chip microcomputer. The upper computer runs self-developed experimental test software, the software is developed under a LabView platform, and the data acquisition card can realize Real-Time acquisition, storage, display and analysis of experimental data by matching with a LabView Real-Time module, so that the whole experimental process is monitored.

In the power supply system of the test system, the output end of the upper computer is connected with the input end of a signal generator, the upper computer outputs amplitude, frequency and phase information of sine and offset signals to a dual-channel signal generator through LabView software, the output end of the signal generator is connected with the input end of a power amplifier, the output end of the power amplifier is connected with an excitation coil (17) and an offset coil (18), the signal generator outputs the sine signals to the excitation coil (17) through the power amplifier, and outputs the offset signals to the offset coil (18) for providing working power supply for the coils.

The temperature control system of the test system mainly comprises a coil framework, a water-cooling joint, a cooling water channel, a cold air exhaust, a fan, a water pump, a water tank, a constant temperature rod, a temperature sensor, a temperature transmitter and a single chip microcomputer. The upper end and the lower end of the coil framework are connected with a standard quick-screwing M5 water-cooling joint through threads, the water-cooling joint is connected with a PVC hose, cooling water is pumped to a cold row from a water tank through a water pump, and the cooling water flows to a cold channel in the coil framework after being cooled by a fan. The heat generated by electrifying the coil is transferred to the copper coil framework through the silicone grease in the coil gap, and the heat transferred to the coil framework by the coil is taken away through the circulating flow of cooling water so as to achieve the purpose of cooling. The heating process is the same, and the cooling water in the water tank is heated through the constant temperature rod, so that the heat is transferred to the coil framework. The upper computer communicates with the single chip microcomputer, the upper computer burns a temperature control program into the single chip microcomputer, the single chip microcomputer collects information of the temperature sensor, judges and controls fan driving voltage, water pump rotating speed and constant temperature rod temperature, and transmits data to the upper computer for recording and monitoring.

The overall framework of the LabView system software of the test system is as follows: the performance test system of the designed magnetostrictive actuator is realized by matching a LabView written upper computer test program with hardware in the test system. Specifically, the system is required to stably acquire, record and display sensor signals at any time according to requirements, for example, fourier transform is performed on output displacement signals to obtain an actuator frequency response curve, and preliminary filtering processing is performed on the output displacement curve and force curve. After data acquisition is completed, a data acquisition text file can be generated, acquired data is played back, and screening, filtering and numerical analysis are performed on the data as required.

Example 2:

when the system of the invention is used for carrying out the magnetostrictive rod characteristic experiment, the following experimental planning design is carried out,

the magnetostrictive actuator has complex nonlinear characteristics of force-electricity-magnetism-heat multi-field coupling when in work, and in order to accurately obtain the characteristics of the magnetostrictive material and the output capacity of the designed magnetostrictive actuator, a series of experiments need to be designed according to the basic characteristics of the magnetostrictive material. These characteristics include, among others, joule effect, frequency doubling effect, hysteresis effect, Δ E effect, etc. In order to explore these characteristics, a performance testing system is required to analyze the electromagnetic, mechanical and thermodynamic characteristics of the magnetostrictive material and its actuator.

In the magnetostrictive material characteristic experiment, the influence of alternating magnetic field frequency, magnetic field intensity, prestress and environmental temperature on magnetostriction needs to be examined.

1) And under the condition that the exciting coil generates different exciting magnetic field frequencies and bias magnetic field strengths, the frequency output by the magnetostrictive material rod. The relationship between the excitation magnetic field and the bias magnetic field is researched, and the feedback is given to the design of the excitation coil and the bias coil and the control of the excitation current and the bias current of the magnetostrictive actuator. And under the high-frequency AC excitation magnetic field, the relationship of frequency doubling effect, hysteresis effect and eddy current linearity.

2) The output force and the output displacement performance of the magnetostrictive rod under different magnetic field strengths are obtained by continuously improving the magnetic field strength to obtain the maximum output force and displacement output by the magnetostrictive material. Theoretically, the magnetic field intensity of the magnetostrictive rod is in direct proportion to the output force and the displacement, but the magnetic field intensity and the output displacement are in a nonlinear relation, and after the saturated magnetostrictive is achieved, the output displacement of the magnetostrictive rod does not change along with the increase of the magnetic field intensity. Since different magnetostrictive materials have different output properties, the test helps to feed back and adjust the driving current and the bias current of the magnetostrictive actuator, so that the magnetostrictive actuator approaches a linear output state.

3) And testing the output force and the output displacement performance of the magnetostrictive rod under different prestress sizes. The test aims to obtain a complete line graph, and the line graph is used as a reference to adjust the prestress so that the actuator works under a more proper load. The magnitude of the prestress, also referred to as the optimum prestress, that produces the maximum output displacement of the magnetostrictive rod is found. The actuator can output more output force or displacement by adjusting the prestress mechanism and the magnetic field of the actuator, and the control requirement is met. And the limit performance of the magnetostrictive rod can be tested.

4) And testing the magnetic induction intensity of the magnetostrictive rod under different prestress values. The magnetic induction intensity of the magnetostrictive rod is directly related to the magnetic domain direction and the output displacement, when more magnetic domains are arranged in the magnetostrictive rod, the same direction with the external magnetic field is formed, the magnetic induction intensity and the magnetic susceptibility of the magnetostrictive rod are higher, and meanwhile, the magnetostrictive displacement is higher. The experiment for designing the influence of prestress on the magnetic induction intensity of the magnetostrictive rod is helpful for researching the change of the magnetic induction intensity and deeply understanding the principle of a magnetic domain bottom layer.

5) Hysteresis experiments of magnetostrictive rods at different excitation current frequencies. On magnetostrictive rods, hysteresis behaves differently as the excitation frequency changes. Hysteresis causes a large energy loss to the output of the magnetostrictive actuator, so that the smaller the hysteresis on the actuator, the better the hysteresis, but the larger the energy loss caused by the hysteresis with the increase of the excitation frequency and the field strength. Hysteresis is inevitable, and when GMA is accurately controlled, the influence of the hysteresis on the output characteristic needs to be calculated. The study of hysteresis models is therefore also of great importance.

In the characteristic experiment of the magnetostrictive actuator, frequency response curves and magnetic flux leakage characteristics of the magnetostrictive actuator under different loads, driving currents and temperatures need to be researched.

1) Comparing the influence of different current amplitudes on the dynamic frequency response curve of a magnetostrictive actuator

2) Comparing the influence of different prestress on the dynamic frequency response curve of the magnetostrictive actuator

3) Comparing the influence of different temperatures on the dynamic frequency response curve of the magnetostrictive actuator

4) Measuring the magnitude of the leakage flux of the magnetostrictive actuator under each of the above conditions

Other reservation experiment requirements: besides the experiment, the designed test system can comprehensively monitor various related variable parameters in the working process of the designed magnetostrictive actuator, and is convenient for analyzing and researching the local and overall working characteristics of the magnetostrictive actuator.

The specific embodiment of this experiment is as follows:

1. and starting the upper computer, detecting the axial stress by the dynamic force sensor, transmitting a force signal to the upper computer, and adjusting the pre-tightening bolt through a numerical value displayed by the upper computer to enable the magnetostrictive rod to be in a proper pre-tightening stress size.

2. And starting a temperature control system, starting a water pump, a constant temperature rod and a fan to work, inputting a preset temperature in a LabView program of an upper computer, and waiting for the temperature in the water tank to reach the preset temperature.

3. And inputting a preset signal waveform to the exciting coil and inputting a preset direct current amplitude to the bias coil in a LabView program of the upper computer. The upper computer transmits the signal data to the signal generator, and the signal is transmitted to the coil as a power supply to excite the magnetostrictive rod to vibrate after being amplified by the power amplifier. The vibration is transmitted to the outside through the upper magnetic conduction block and the ejector rod.

4. The working environment temperature of the magnetostrictive rod and the working temperature of the coil are respectively measured through the first temperature sensor and the second temperature sensor, and the temperature control system is adjusted through temperature. The output force and the output displacement performance of the magnetostrictive material under different temperature environments can be measured through the temperature adjusting system. The magnetic field intensity change when the first Hall probe measures the temperature is matched, the output displacement change is measured by the eddy current displacement sensor, and the output force change is measured by the dynamic force sensor.

5. When the output force of the magnetostrictive rod is measured, the ejector rod and the actuator base are fixed, the output force of the magnetostrictive rod is measured by using the dynamic force sensor, and the dynamic force sensor transmits force information to the upper computer for recording.

6. When the output displacement of the magnetostrictive rod is measured, the output displacement of the ejector rod is measured by using the eddy current displacement sensor, and the eddy current displacement sensor transmits displacement information to the upper computer for recording.

7. When the frequency response curve of the actuator is measured, currents with different amplitudes and 0-1kHz are input to the exciting coil in a LabView program of the upper computer, the time domain displacement of the exciting coil is measured by using the eddy current displacement sensor, and the frequency response curve of the actuator under different exciting amplitudes can be obtained after Fourier transform is carried out on the measurement result. And applying external load on the ejector rod to measure the frequency response curve of the actuator under different loads.

8. And measuring the strain of the central point of the magnetostrictive rod by using a strain gauge, and transmitting strain information to the upper computer for recording.

9. And the first Hall probe is used for measuring the axial magnetic field in the magnetostrictive actuator, the second Hall probe is used for measuring the leakage amount of the magnetic field outside the magnetostrictive actuator, and the measured magnetic field information is transmitted to the upper computer for recording.

Claims

1. The utility model provides a leak protection magnetism, high damped magnetostrictive actuator capability test system which characterized in that: comprises a magnetostrictive actuator system, a sensing system, an information acquisition control system, a power supply system and a temperature control system which are connected with the magnetostrictive actuator system; the magnetostrictive actuator system comprises a prestress applying mechanism formed by a metal rubber piece and a pretightening bolt (2), a magnetostrictive rod (16), a magnetic circuit system and a magnetostrictive actuator with a coil framework arranged inside;

2. The magnetic leakage prevention and high damping performance test system for the magnetostrictive actuator according to claim 1, characterized in that: the ejector rod receives external excitation and then performs reciprocating motion in the axis direction; when the ejector rod (1) moves downwards, the metal rubber (3) clamped between the boss of the ejector rod and the shaft sleeve bears part of external load and consumes part of impact energy through self damping; when the ejector rod moves upwards along the axis, the metal rubber between the pre-tightening bolt (2) and the boss of the ejector rod bears load and consumes impact energy in the axis direction.

3. The system for testing the performance of the leakage-proof high-damping magnetostrictive actuator according to claim 2, characterized in that: the external excitation is applied by an electromagnetic field generated by an excitation coil (17) and a bias coil (18) at the coil skeleton; the coil framework is arranged between the shaft sleeve (7) and the base of the magnetostrictive actuator.

4. The magnetic leakage prevention and high damping performance test system for the magnetostrictive actuator according to claim 3, characterized in that: the coil framework (12) is arranged on a magnetostrictive actuator base, the upper end and the lower end of the coil framework are round tables, and rectangular coil slots (12-1) and sensor slots (12-2) are arranged on the round tables at the lower end;

an upper magnetic conduction block (11), a magnetostrictive rod and a lower magnetic conduction block (19) are arranged in a tubular cavity in the center of the coil framework; an exciting coil (17) is wound on the inner side of the coil framework (12), and a bias coil (18) is wound outside the exciting coil (17); the coil conducting wire is led out through a coil wire slot (12-1), an inner magnetic conduction frame wire hole (13-1), a middle magnetic conduction frame wire hole (14-1) and an outer shell wire hole (15-1);

after current is introduced into the hollow cylindrical excitation coil (17) and the bias coil (18), a magnetic field is generated in the direction of the central axis of the coils, and magnetic induction lines of the magnetic field circulate along a magnetic conduction loop formed by the magnetostrictive rod (16), the upper magnetic conduction block (11), the inner magnetic conduction end cover (9), the inner magnetic conduction frame (13), the inner magnetic conduction base (21) and the lower magnetic conduction block (19);

the test system also comprises a magnetic flux leakage measuring mechanism at the coil framework; the magnetic flux leakage measuring mechanism forms a magnetic conduction loop by a magnetostrictive rod, an upper magnetic conduction block, a lower magnetic conduction block, an inner magnetic conduction end cover (9), an inner magnetic conduction frame (13) and an inner magnetic conduction base (21), and forms a magnetic flux leakage recovery loop by a middle magnetic conduction end cover (6), a middle magnetic conduction frame (14) and a middle magnetic conduction base (22); a magnetism isolating end cover (8) is arranged between the inner magnetic end cover and the middle magnetic end cover;

the inner magnetic conduction base is connected with the middle magnetic conduction base, so that the magnetic conduction loop is separated from the magnetic flux leakage recovery magnetic circuit, and the magnetic flux leakage recovery magnetic circuit conducts the magnetic flux leakage back to the magnetic conduction loop when electromagnetic field magnetic flux leakage generated by the excitation coil (17) and the bias coil (18) is recovered;

the teslameter is connected with a second Hall probe arranged on the Hall probe bracket (27) to measure the leakage quantity of the magnetic field generated by the exciting coil (17) and the bias coil (18) outside the shell (15); the Hall probe bracket (27) is fixed on the flange threaded hole (24-2) of the actuator base through threaded connection.

5. The magnetic leakage prevention and high damping performance test system for the magnetostrictive actuator according to claim 4, characterized in that: the sensing system further comprises a first patch temperature sensor (25-1) adhered to the surface of the magnetostrictive rod (16), a strain gauge (26) used for collecting strain information of the magnetostrictive rod, a first Hall probe (20-1) positioned in the lower magnetic conduction block slot (19-1) and used for measuring the axial magnetic field intensity of the magnetostrictive rod, a second patch temperature sensor (25-2) adhered between the exciting coil (17) and the bias coil (18), and a dynamic force sensor (23) arranged in a cylindrical groove in the center of the actuator base (24); the ejector rod (1), the upper magnetic conduction block (11), the magnetostrictive rod (16), the lower magnetic conduction block (19), the inner magnetic conduction base (21), the middle magnetic conduction base (22) and the dynamic force sensor (23) are positioned on the same axis; the dynamic force sensor (23) is clamped in a gap between the middle magnetic conduction base (22) and the actuator base (24);

when external load is input from the ejector rod (1), the external load and prestress are transmitted to the dynamic force sensor (23) along the axial direction, so that the force measurement is realized; the dynamic force sensor lead is led out of an information acquisition control system of an upper computer through an actuator base wire slot (24-1) and a shell wire hole (15-2);

the eddy current displacement sensor (28) is fixed on the end cover (4) by using threads, when a coil generates a magnetic field to excite the magnetostrictive rod (16) to output displacement, the displacement is transmitted to the ejector rod (1) through the upper magnetic conduction block (11), and the eddy current displacement sensor (28) obtains the displacement output of the actuator by measuring the displacement of the ejector rod (1) in the axial direction; when a load is applied to the outside, the sensing system measures the deformation of the inner part of the magnetostrictive actuator caused by the external load through an eddy current displacement sensor (28);

the temperature control system comprises a cooling water path arranged in the coil framework, a water pump of the cooling water path is arranged in an external water tank, and cooling water of a pipeline in the cooling water path is driven to circularly flow;

6. the system for testing the performance of the leakage-proof high-damping magnetostrictive actuator according to claim 5, characterized in that: in the magnetostrictive actuator, a shell (15) is fixedly connected with an end cover (4) through a bolt, a circular pressing ring (5) is arranged on the inner side of the end cover (4), a pre-tightening bolt (2) is connected with the end cover (4) through a thread, and an ejector rod (1) is arranged in a groove of an upper magnetic conduction block (11). A bolt hole (24-4) in the actuator base (24) is used for fixing the magnetostrictive actuator on the T-shaped groove platform;

the cooling water channel is a hollow cylindrical water cooling channel outside the central cavity of the coil skeleton, and the water cooling channel comprises a stainless steel quick-screwing standard part; the upper part and the lower part of the cylindrical water cooling channel are respectively communicated with an upper linear cooling channel (12-3) and a lower linear cooling channel (12-4), and the two linear cooling channels are connected with a water cooling head (10) by using threads; the water-cooling head at the upper end passes through the through hole (14-3) on the middle magnetic conduction frame and the through hole (15-4) on the shell, and the water-cooling head at the lower end passes through the wire hole (14-1) of the middle magnetic conduction frame and the wire hole (15-1) on the shell.

7. The magnetic leakage prevention and high damping performance test system for the magnetostrictive actuator according to claim 3, characterized in that: the exciting coil and the bias coil are coated with silicone grease when the coils are wound, and the silicone grease fills gaps around the conducting wires to increase heat transfer efficiency; the magnetic conduction material of the magnetic flux leakage measuring mechanism is made of electrician pure iron; the material of the magnetism isolating end cover is H62 brass material.

8. The magnetic leakage prevention and high damping performance test system for the magnetostrictive actuator according to claim 3, characterized in that: in the magnetic field design of the exciting coil and the bias coil, a field intensity range with the maximum magnetostriction rate variation of the magnetostrictive rod is selected as a working interval, in the interval, the magnetostriction variation of the magnetostrictive rod is obvious, and the field intensity and the magnetostriction rate are approximate to a linear relation.

9. The magnetic leakage prevention and high damping performance test system for the magnetostrictive actuator according to claim 3, characterized in that: the magnetic fields of the exciting coil and the bias coil depend on the ampere turns and the geometric size of the coil; the actuator is characterized in that a main coil inside the actuator and all parts of a coil framework are provided, a bias coil is embedded in the outer layer of an excitation coil, the excitation coil is arranged inside the main coil, a magnetostrictive rod is arranged in the center of the framework, and the size of the main coil used for designing the magnetic field intensity of any point on a shaft line is calculated in advance;

the number of coil turns n per unit length is:

θ ₁ ，θ ₂ the geometrical relationship of the two angles is as follows:

the magnetic induction intensity generated by each layer of coil is as follows:

the magnetic induction intensity B of any point P can be obtained as follows:

magnetic field intensity H _P Comprises the following steps:

L _coil ＝(1.05～1.1)L _GMM A formula ten;

determination of the magnetic field strength H _P And the total ampere-turns NI of the coil, and further distributing the proportion of the exciting coil in the coil to the total coil after the total coil size R2 is designed in a substituting mode.

10. The magnetic leakage prevention and high damping performance test system for the magnetostrictive actuator according to claim 3, characterized in that: in an alternating current magnetic field and bias magnetic field experiment, according to the frequency doubling principle of a magnetostrictive rod, presetting currents I with the same magnitude applied on an excitation coil and a bias coil; the exciting coil and the bias coil are separated, the distances between the two groups of coils and the magnetostrictive rod are unequal, the field intensity difference generated by the distances is made up by designing the coils with different sizes, and the specific method comprises the following steps:

after the current relationship between the two coils is determined, when the two groups of coils need to generate equal field intensity on the axis, the size relationship of the two groups of coils is determined according to a formula, and the number of turns of the exciting coil is set to be N _{Movable part} Excitation magnetic field intensity of H _{Movable part} Bias coil turns number N _Quiet Bias magnetic field intensity H _Quiet If the two relations are: h _{Movable part} ≤H _Quiet Substituting it into the formula can result:

wherein, the first and the second end of the pipe are connected with each other,

N _{movable part} ＝(R ₃ -R ₁ )×n ₂ ×L _coil ×n ₁ A formula twelve;

N _quiet ＝(R ₂ -R ₃ )×n ₂ ×L _coil ×n ₁ A formula thirteen;

the formula is derived: