JP2003204609A - Magnetic levitation apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetic levitation apparatus which enables structure simplification, size reduction, cost reduction, and reliability improvement thereof. <P>SOLUTION: There is provided an auxiliary support means 31, which holds a levitation unit 11 in an attitude its landing state; an attitude estimating means 33 which is provided in an attracting force control means 15 for controlling the attracting of a magnet unit 7, and estimates the attitude of the levitation unit 11 in a levitated state; a landing detecting means 29 detecting the landing of the levitation unit 11; an attitude operating means 35 operating the attitude of the levitation unit 11 in the landing state; an initial value setting means 39 giving an initial value, which is a calculated gap between the magnet unit 7 in the landing state and a guide 13 made of ferromagnetic material, to the attitude estimating means 33; and an estimation initializing means 13, which initializes the attitude estimating means 33 to have an operation starting state. As a result of such a constitution, when levitation is started, the gap information close to an actual value can be estimated. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic levitation device for supporting a levitation body by a suction type magnetic levitation in a non-contact manner.

[0002]

2. Description of the Related Art Normal-conducting suction type magnetic levitation has no noise or dust generation and has already been put into practical use in railways such as HSST (Ultra High Speed Surface Transport) and Transrapid, and in clean room transportation systems in semiconductor factories. ing. The magnetic levitation system is inherently unstable in the normal-conduction magnetic levitation in which the electromagnet is placed opposite to the ferromagnetic member, and the levitation body is levitated by utilizing the attractive force generated between the electromagnet and the ferromagnetic member. In order to stabilize this, the levitation gap length, its speed, acceleration, electromagnet exciting voltage, and electromagnet exciting current are detected, and these are fed back to the attractive force control means to perform attractive force control. Has been done.
For this reason, in order to ensure the stability of the system, it is necessary to detect the flying gap length in the conventional technique, and the use of the gap sensor cannot be avoided. Further, in order to detect the gap length between the ferromagnetic member and the electromagnet with the gap sensor, a sensor target suitable for the gap sensor to be used is required, and the sensor target must be installed along with the ferromagnetic member. It was

As described above, when the levitation gap length is used for stabilizing the magnetic levitation system, a gap sensor and a sensor target are required, which increases the cost of the apparatus. Further, it is necessary to secure a space for mounting the gap sensor and a space for the sensor target, which has been an obstacle to downsizing of the device. In particular, in railways and transport systems, a branch point is provided in the track composed of ferromagnetic guides, so it is necessary to have a mechanism that does not interfere with the detection of the gap length because the sensor target and the guide intersect. This also causes the system to be complicated.

In order to solve such a problem, for example, a method of estimating the gap length from an electromagnet exciting current by an observer (state observer) (Mizuno, et al .: "Study on Practical Use of Displacement Sensorless Magnetic Bearing", Proceedings of the Institute of Electrical Engineers of Japan D Volume, 116, No. 1, 35 (1996)) or a method of including gap information in the phase difference signal between the electromagnet exciting voltage and the exciting current generated by AC magnetic levitation, and feeding this back to the electromagnet exciting voltage for stabilization. (Moriyama: "AC Magnetic Levitation Using Differential Feedback Power Amplifier" Proceedings of the 1997 Annual Meeting of the Institute of Electrical Engineers of Japan,
No.1215), the switching frequency is changed by comparing the electromagnet excitation current value with the hysteresis current reference value with a hysteresis comparator, and switching the electromagnet excitation voltage to negative when the excitation current is larger than the reference value and to positive when it is smaller. Stabilizes the levitation system by proportional to the levitation gap length (Mizuno, et al .:
"Self-sensing magnetic levitation using a hysteresis amplifier", Transactions of the Society of Instrument and Control Engineers, 32, No. 7, 1043 (199)
Methods such as 6)) have been proposed as sensorless methods that eliminate the gap sensor.

However, even with such a solution, when the observer is used, since the gap length is derived from the linear model of the magnetic levitation system in the levitation state, the levitation gap length when not in the levitation state. However, there is a problem in that it is difficult to estimate the levitation and it is difficult to start levitation, and once the levitation body comes into contact with another structure, it cannot return to the levitation state again. Furthermore, when controlling the electromagnet excitation voltage with a physical quantity that includes gap information other than the observer, the levitation control system is a non-linear system, so it is difficult to determine stability, or the mass change of the levitation body or temperature rise due to excitation. However, there is also a problem that it becomes difficult to maintain the floating state if the electric resistance of the electromagnet coil fluctuates.

[0006]

As described above, in the conventional magnetic levitation apparatus, the levitation gap length of the levitation body is fed back to the attraction force control means to realize a stable magnetic levitation state of the levitation body. Therefore, the gap sensor and the sensor target are indispensable. For this reason, there is a problem that the device becomes large and complicated, resulting in cost increase.
Moreover, if the information on the gap length is fed back to the suction force control means without using the gap sensor in order to avoid such a problem, the stability and the reliability of the operation of the levitation system are significantly impaired, so that the gap sensor is eventually used. It has been difficult to avoid the problems of increased complexity and size of the device and increased cost.

The present invention has been made under the above circumstances, and an object thereof is to provide a magnetic levitation device capable of simplifying and downsizing the device, reducing cost, and improving reliability. It is in.

[0008]

In order to achieve the above object, a magnetic levitation apparatus according to a first aspect of the present invention comprises a magnet unit including an electromagnet, a levitation body supported by the magnet unit, and a magnet unit. Maintains the positional relationship between the levitation body and the ferromagnetic member when the levitation body is not in a levitation state, and the ferromagnetic member that supports the levitation body in a non-contact manner by the attraction force of the magnet unit, with the magnetic poles facing each other through the air gap. Auxiliary supporting means, a sensor section for detecting an exciting current of the electromagnet, an attitude estimating means for estimating the attitude of the levitation body with respect to the ferromagnetic member based on the output of the sensor section, the levitation body and the ferromagnetic member or the auxiliary supporting means. A contact detecting means for detecting the contact of the floating body, an attitude calculating means for calculating the attitude of the floating body relative to the ferromagnetic member at the time of contact based on the output of the contact detecting means, and an attitude estimating means for contact at the time of contact based on the output of the contact detecting means Of the estimation initialization means for initializing the state at the start of the work, the initial value setting means for setting the output value of the posture calculation means as the initial value of the posture estimation means when the posture estimation means is initialized, and the posture estimation means An attraction force control means having a driving means for controlling the attraction force of the magnet unit so that the magnetic circuit formed by the magnet unit via the air gap and the ferromagnetic member is stabilized based on the output of the output. It is characterized by

According to a second aspect of the present invention, in the magnetic levitation device according to the first aspect, the magnet unit includes a permanent magnet arranged so as to share the magnetic path with the magnetic flux of the electromagnet in the air gap. Characterize.

According to a third aspect of the present invention, in the magnetic levitation device according to the second aspect, the attraction control means stabilizes the magnetic circuit while converging the exciting current of the electromagnet to zero based on the output of the sensor section. It is characterized by being provided with zero power control means.

The invention according to claim 4 is the magnetic levitation device according to claim 3, characterized in that the zero power control means is constituted by attitude estimation means.

According to a fifth aspect of the present invention, in the magnetic levitation device according to the first aspect, the attitude estimating means is based on the exciting current of the electromagnet and the exciting voltage for generating the exciting current, and thus the ferromagnetism of the levitation body is increased. It is characterized by estimating a posture with respect to a member and a temporal change of the posture.

According to a sixth aspect of the present invention, in the magnetic levitation device according to the first aspect, the posture estimating means inputs the output of the posture estimating means, and when the input is within a predetermined saturation range, the input is made. It is characterized in that the apparatus further comprises an estimated output limiting means for outputting the value as it is and outputting the saturated value when it is outside a predetermined saturation range.

According to a seventh aspect of the present invention, in the magnetic levitation device according to the first aspect, the attraction force control means calculates an electromagnet excitation voltage based on the output of the estimated output limiting means, and outputs the output to the driving means. It is characterized in that it is provided with an exciting voltage calculation unit for giving.

According to an eighth aspect of the present invention, in the magnetic levitation device according to the seventh aspect, when the excitation voltage control means inputs the output of the excitation voltage calculation unit and the input is within a predetermined saturation range. Is provided with voltage output limiting means for outputting an input value and a saturated value when the input value is out of a predetermined saturation range.

According to a ninth aspect of the present invention, in the magnetic levitation device according to the seventh aspect, the exciting voltage computing section contributes to the degree of freedom of movement of the levitation body based on the output of the estimated output limiting means. Is provided, a mode excitation voltage calculator is provided for calculating the mode-specific excitation voltage represented by a linear combination of electromagnet excitation voltages.

According to a tenth aspect of the present invention, in the magnetic levitation device according to the ninth aspect, the attractive force control means is a linear combination of electromagnet exciting currents that generate an attractive force that contributes to the freedom of movement of the levitation body. It is characterized in that it is provided with a mode excitation current calculation unit for calculating the current for each mode shown.

According to an eleventh aspect of the present invention, in the magnetic levitation device according to the ninth aspect, the mode excitation voltage calculation section includes voltage output limiting means for inputting the output of the mode excitation voltage calculation section. Is characterized by.

According to a twelfth aspect of the present invention, in the magnetic levitation apparatus according to the tenth aspect, the attitude estimating means is based on the output of the mode-specific exciting current calculator and the output of the mode exciting voltage calculator of the electromagnet. Is estimated with respect to the ferromagnetic member and the time change of the attitude.

According to a thirteenth aspect of the present invention, in the magnetic levitation apparatus according to the first aspect, the posture estimating means has an integrator, and when the contact detecting means detects a contact, the estimation initializing means integrates the integral. When the integration of the instrument is stopped and the integration result becomes the value output by the initial value setting means, and the contact detection means stops detecting contact, the value output by the initial value setting means at the time of the contact immediately before that is the initial value. Is characterized in that the estimation initialization means starts the integration of the integrator.

According to a fourteenth aspect of the present invention, in the magnetic levitation device according to the seventh aspect, the attitude estimating means is an exciting current of the electromagnet inputted to the attitude estimating means when the contact detecting means detects the contact. And a switching means for switching the output of the exciting voltage calculating section to zero input and switching the zero input to the exciting current of the electromagnet or the output of the exciting voltage calculating section when the contact detecting means stops detecting contact.

According to a fifteenth aspect of the present invention, in the magnetic levitation apparatus according to the tenth aspect, when the attitude estimation means detects contact by the contact detection means, mode excitation is input to the attitude estimation means. The output of the current calculator and the mode excitation voltage calculator should be switched to zero input, and when the contact detection means stops detecting contact, it should have switching means for switching the zero input to the output of the mode excitation current calculator or excitation voltage calculator. Is characterized by.

According to a sixteenth aspect of the present invention, in the magnetic levitation device according to the first aspect, the auxiliary supporting means is attached to the levitation body.

According to a seventeenth aspect of the present invention, in the magnetic levitation device according to the first aspect, the auxiliary supporting means is attached to the ferromagnetic member.

The invention according to claim 18 is the magnetic levitation apparatus according to claim 1, wherein the magnet unit is attached to the levitation body.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS <Principle of the Invention> Here, the principle of the magnetic levitation device of the present invention will be described. In FIG. 1, the one-mass-system magnetic levitation device is indicated by reference numeral 1 as a whole.

The magnetic levitation device 1 is a levitation body 1 including a magnet unit 7 composed of a permanent magnet 3 and an electromagnet 5, and a load load 9 levitated by the magnet unit 7.
1, a guide 13 made of a ferromagnetic member for supporting the levitation body 11 in a non-contact manner by the magnetic attraction force acting on the magnet unit 7 and the magnet unit 7, and controlling the attraction force of the magnet unit 7. And a suction force control means 15 for stably supporting the floating body 11 in a non-contact manner.

Yoke 1 is attached to each of the magnetic pole ends of the permanent magnet 3.
7a and 17b are arranged so as to abut on their side surfaces, and the electromagnet 5 is formed by winding coils 19a and 19b around yokes 17a and 17b. The magnetic flux generated by the permanent magnet 3 passes through a closed magnetic circuit composed of the yoke 17a, the guide 13, the yoke 17b, and the permanent magnet 3. Both coils 19a and 19b are connected in series, and by passing a current of a predetermined polarity through them, the generated magnetic flux is superposed on the generated magnetic flux of the permanent magnet 3 to strengthen it,
On the contrary, the generated magnetic flux of the permanent magnet 3 can be canceled and weakened.

The current control of the electromagnet 5 is performed by the attraction force control means 15
Done by The attraction force control means 15 determines, based on the flying gap length z obtained by the gap sensor 21 and the exciting current i _z obtained by the current sensor 23,
An exciting voltage calculator 25 for calculating the exciting voltage of the electromagnet 5,
A driver 27 that supplies a required exciting current i _z to the electromagnet 5 based on the output of the exciting voltage calculator 25 is provided.

The magnetic levitation system of the magnetic levitation apparatus 1 is linearly approximated near the levitation gap length z ₀ when the attractive force of the magnet unit 7 becomes equal to the weight of the levitation body 11, and is described by the following differential equation. .

[Equation 1] Wherein (1), m is the mass of the floating body 11, z is floating gap length, i _z the exciting current of the electromagnet 5, phi is the main magnetic flux, e _z is the excitation voltage of the electromagnet 5 of the magnet unit 7, delta steady Ascent (z
= z ₀ , i _z = i _z0 ), the symbol “・” is d / dt, the partial differential ∂ / ∂h (h = z, i) is the steady floating state (z = z ₀ , i _z = i _z0 )
The respective partial differential value of the partial differential function at, L _z0 is

[Equation 2] Becomes In the equation (3), each element of x is the state quantity of the levitation system, C is an output matrix, and is determined by the state quantity detection method used to calculate e _z . The magnetic levitation device 1 uses the gap sensor 21 and the current sensor 23, and when the velocity is obtained by differentiating the signal of the gap sensor 21, C becomes a unit matrix. Here, F is a proportional gain compensator for x, K _i is an integral gain, and the excitation voltage e _z is, for example,

[Equation 3] If given by, the magnetic levitation device 1 is Japanese Patent Publication No. 06-24405.
It emerges with the zero power control found in the publication. here,
It goes without saying that the excitation voltage calculation unit 25 calculates the equation (6).

As an estimating means for estimating the floating gap length deviation Δz and its speed d (Δz) / dt from the exciting current Δi _z in the magnetic levitation apparatus 1 of the equation (1) without using the gap sensor 15, For example, consider the case where a same-dimensional state observer (hereinafter referred to as an observer) is applied. At this time,
According to the linear control theory, the observer is

[Equation 4]

Therefore, in the magnetic levitation apparatus 1'according to the present invention shown in FIG. 2, the gap sensor 21 is omitted, and instead the levitation body 11 and its vicinity are changed from the non-contact state to the contact state. For example, a contact detection unit 29 that detects the piezoelectric rubber 28, and an auxiliary support unit 31 that maintains the attitude of the floating body at the time of contact are provided. Further, the exciting voltage calculation unit 25 estimates the flying gap length deviation Δz and its speed d (Δz) / dt from the exciting current Δi _z . For example, the posture estimating unit 33 configured by an observer and the auxiliary supporting unit 31 maintain the same. Posture calculating means 35 for calculating x ₀ which should be the initial value of the observer when the posture is changed to the floating state, estimation initialization means 37 for returning the output value of the observer to the initial state by contact, and initializing The converted observer is provided with an initial value setting means 39 for setting x ₀ calculated by the attitude calculation means as an initial value. Then, the estimated excitation current Δi _z , the floating gap length deviation Δz, and the speed d (Δz) / dt thereof are used as the excitation voltage calculation unit 2
5, and the electromagnet 5 is excited via the driver 27. In this way, by initializing the observer and giving a predetermined initial value, even if the robot is levitated from the stopped state or the levitated state is changed to the contact state due to external force or other reasons, the exciting current Δi _z From this, it is possible to estimate the levitation gap length deviation Δz and its velocity d (Δz) / dt while suppressing the error from the beginning, and it is possible to reliably transfer the levitation body 11 to the levitation state and maintain the levitation state. .

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<First Embodiment> FIGS. 3 to 7 show the main parts of a magnetic levitation apparatus according to the first embodiment.

As shown in FIG. 3, this magnetic levitation device 40
Is a guide rail 4 made of a ferromagnetic member attached to the lower surface of a top plate 42 that constitutes the ceiling of the building by a predetermined attachment method.
4 and an upper support member 46 composed of a plane correction member 45 made of a non-magnetic material that corrects unevenness generated by attaching the guide rail 44 to the top plate 42 to a flat surface in a predetermined range of the top plate 42, A lower support member 52 formed by digging a groove 50 having a predetermined shape on the floor 48, and an upper support member 4
6 and the lower support member 52, and a partition 54 that is geometrically prevented from falling due to the gap between the two. The guide rail 44 has an upper guide groove 56 formed at a predetermined position on the lower surface thereof and having an inverted U-shaped cross section for guiding the upper portion of the partition body 54.

The partition 54 is attached to the partition 54,
Two magnet units 60a and 60b that support the partition body 54 in a non-contact manner with respect to the guide rail 44, and attraction force control means that controls the attraction force of the magnet units 60a and 60b to support the partition body 54 in a non-contact manner. Control device 70
A power supply device 72 for supplying necessary power to the magnet units 60a and 60b and the control device 70, and the magnet unit 6
0a, 60b are attached via a base plate 62, and a frame portion 80, and a partition plate 82 fitted in the frame portion 80 and made of, for example, glass, aluminum, wood, paper or the like.

The magnet units 60a and 60b are permanent magnets 6
4 and electromagnets 66, 66 ',
It is assembled in a U-shape as a whole so that the tip of 6 ′ faces the lower surface of the guide rail 44. Electromagnet 6
6, 66 'is a prismatic iron core 68 (68') coil 69
(69 ') is inserted, and the coils 69 and 69' are connected in series so as to strengthen each other's magnetic flux during excitation. At the tips of the electromagnets 66, 66 ', the magnet units 60a, 60b' are prevented from being attracted and fixed to the guide rail 44 by the attraction force of the permanent magnet 64 when they are not excited, and even in the attracted state. Piezoelectric rubbers 73a and 73b surface-treated with a solid lubricating member are attached so as not to hinder the movement of the partition body 54. Here, the piezoelectric rubbers 73a and 73b have a property that the electric resistance becomes close to zero due to the attraction force when the magnet units 60a and 60b come into contact with the guide rails 44, respectively.
It is suitable for detecting the contact state of.

The frame portion 80 has an inverted U-shaped cross section and is attached to an upper portion of a fixed base 83, a support rod 84 fixed to the fixed base 83, and a tip portion of the support rod 84 rotatably. A guide shoe 86 that is attached and fits into the upper guide groove 56 to guide the upper portion of the partition body 54 along the guide rail 44, and a lower portion of the partition body 54 that fits into the groove 50.
And two guide wheels 88, 88 'for guiding along, and a guard member 89 made of a soft material such as soft rubber to prevent an accident when the partition body 54 is caught when moving along the wall surface. , A side frame 91 having a U-shaped cross section for sandwiching the partition plate 82 from the left and right in the concave portion, and guide wheels 88, 88 fixed to the lower end surfaces of the left and right side frames 91 by a predetermined method at both ends of the lower surface. The bottom frame 95 having the axle 93 and the bottom frame 95 made of hard piezoelectric rubber and attached to the bottom surface of the bottom frame 95 directly attaches the floor frame 95 to the floor 48 when the attraction force of the magnet unit 60 is lost.
Buffer member 97 for preventing contact with the upper surface of the partition and detecting contact of the partition body 54 as a floating body, and the upper base 10.
1, a lower base 103 and a side plate 104 are provided in a box shape, each of which is provided with a control device 70 and a power supply device 72 which are divided into two parts, and a magnet unit 60 is attached to an upper surface of the upper base 101 and a lower surface of the lower base 103. In addition, the upper end surfaces of the left and right side surface frames 91 are configured with an upper frame 105 fixed by a predetermined method. The upper side of the upper frame 105 has magnet units 60a, 6
A cover 107 that blocks 0b from the field of view is attached,
The design of the magnetic levitation device 10 is improved.

Each attraction force of the magnet units 60a and 60b is controlled by the controller 70, and the partition 54 is supported in a non-contact manner with the guide rail 44.

Although the control device 70 is structured as a divided type as shown in FIGS. 5 and 6, for example, FIG.
As shown in (1), they are functionally integrated into one. In the block diagrams of FIG. 8 and subsequent figures, arrow lines indicate signal paths and bar lines indicate power paths around the coil 40. Further, in the magnet unit 60a, the two coils 69 and 69 'connected in series will be collectively referred to as a coil 69a, and similarly, the two coils 69 and 69' of the magnet unit 60b will be referred to as a coil 69b.

The control device 70 is attached to the frame portion 80 and detects the exciting current of the magnet units 60a and 60b, and the coils 69a and 69b so that the magnet units 60a and 60b support the partition 54 in a non-contact manner.
An arithmetic circuit 112 that calculates the applied voltage to the coils based on the signal from the sensor unit 111; and power amplifiers (power amplifiers) 113a and 113b that supply an exciting current to the coils 69a and 69b based on the output of the arithmetic circuit 112. And these two magnet units 60a, 60b
The suction force of is independently controlled in the z-axis direction and around the y-axis. The power amplifiers 113a and 113b are provided with cooling fins 114 mounted on the upper surface of the upper base 101 for cooling.
Is attached to.

The power supply device 72 is a power amplifier 113a, 1
In addition to supplying power to 13b, it also supplies power to the constant voltage device 118 that supplies power to the arithmetic circuit 112 at a constant voltage. This power supply device 72 is a power amplifier 113.
In order to supply power to a and 113b, it has a function of converting AC power supplied from outside the partition 54 via a power supply line (not shown) into DC suitable for power supply to the power amplifier. . The constant voltage device 118 is the power amplifier 1
Even if the voltage of the power supply device 72 fluctuates due to supply of a large current to the power supply circuit 13, power is always supplied to the arithmetic circuit 112 at a constant voltage. Therefore, the arithmetic circuit 112 always operates normally.

The sensor section 111 includes coils 69a and 69b.
The current detectors 121a and 121b for detecting the current value of

The arithmetic circuit 112 controls the magnetic levitation of the partition body 54 for each motion coordinate system shown in FIG. That is, control is performed in the z mode (vertical movement mode) that represents vertical movement along the z coordinate of the center of gravity of the partition body 54, and the ξ mode (pitch mode) that represents pitching around the center of gravity of the partition body 54. For these two modes, the coil exciting currents of the magnet units 60a and 60b are detected based on the principle of the invention described above, and magnetic levitation control is performed.

More specifically, the arithmetic circuit 112 operates as follows.
Is configured. From the current detectors 121a and 121b
Excitation current detection signal i_a， I_bFrom each current setting value i
_a0， I _b0Current deviation signal Δi obtained by subtracting_a, Δi_bTo
For subtractors 123a and 123b for calculation and movement in the z direction
Related current deviation Δi_z, Pitching around the center of gravity
Current deviation Δi_ξAs a mode excitation current calculation unit
Exciting current deviation coordinate conversion circuit 125 of
Output Δi of standard conversion circuit 125_z, Δi_ξTo z, ξ
Vertical deviation of the center of gravity of the partition 54 from the predetermined position
Vertical motion mode figure for estimating Δz and its velocity d (Δz) / dt
The force estimating means 127a, the pitch deviation Δξ of the partition 54 and
Pitch mode attitude estimation that estimates the velocity and its velocity d (Δξ) / dt
Means 127b, piezoelectric rubbers 73a, 73b and cushioning members
97 to the upper support member 46 of the partition 54.
Or contact detection means for detecting contact with the lower support member 52
129, based on the contact signal from the contact detection means 129
From the posture of the partition 54 at the time of contact, the vertical deviation in the z mode
Difference Δz₀Attitude calculation means 131a for calculating
Pitch deviation at₀Attitude calculation means 13 for calculating
1b and the output Δz of the attitude calculation means 131a₀Pose estimation
It is given to the vertical motion mode posture estimation means 127a as an initial value.
Vertical movement mode initial value setting means 133a and a posture calculator
Output of stage 131b Δξ₀As the initial value for pose estimation.
Initial value setting means to be given to the Q-mode attitude estimation means 127b
133b and vertical motion mode posture estimation means until just before contact
Vertical deviation Δz estimated by 127a and its speed d (Δz) /
dt and excitation current deviation Δi_zUp and down resetting the estimate of
The motion mode estimation initialization means 135a and the
Pitch estimated by the touch mode attitude estimation means 127b
Deviation Δξ, its speed d (Δξ) / dt and exciting current deviation Δi
_ξPitch mode estimation initialization means for resetting the estimated value of
135b and a mode in which the partition 54 is stably magnetically levitated
Separate electromagnet control voltage e_z, e_ξVertical movement mode posture
Estimating means 127a and pitch mode attitude estimating means 12
An excitation voltage calculation unit 136 that calculates based on the output of 7b;
Vertical movement mode control voltage calculation circuit 137a and
Pitch mode control voltage calculation circuit 137b
Output e of the control voltage calculation circuits 137a and 137b_z, e_ξOr
From each of the magnet units 60a and 60b
Voltage e_a, e_bAs the excitation voltage calculation unit 136 that calculates
It is composed of a control voltage coordinate reverse conversion circuit 139. That
Then, the calculation result of the control voltage coordinate reverse conversion circuit 139, that is,
Voltage e mentioned above_a, e_bAre power amplifiers 113a and 113b
Given to.

Here, since the posture of the partition body 54 is maintained by the upper support member 46 and the lower support member 52 when the partition body 54 contacts, the upper support member 46 and the lower support member 52 are separated from each other in this embodiment. It constitutes an auxiliary supporting means.

When the partition body 54 is in the contacting position, the magnet units 60a and 60b are placed in the piezoelectric rubbers 73a and 7b.
3b in contact with the upper supporting member 46 (the gap length of the magnet unit 60a is z _a1 , the magnet unit 6 is
0b has a gap length of z _b1 ) The bottom frame 95 is in contact with the lower support member 52 via the cushioning member 97 (the gap length of the magnet unit 60a is z _a2 , and the gap length of the magnet unit 60b is
z _b2 ), the posture in which the magnet unit 60 a contacts the upper support member 46 via the piezoelectric rubber 73 a and the bottom frame 95 contacts the lower support member 52 via the buffer member 97 (the gap length of the magnet unit 60 a is z _a3 , the gap length of the magnet unit 60 b is z _b3 ), the magnet unit 60 b contacts the upper support member 46 via the piezoelectric rubber 73 b, and the bottom frame 95 contacts the lower support member 52 via the buffer member 97. There are four patterns of the posture (the gap length of the magnet unit 60a is z _a4 and the gap length of the magnet unit 60b is z _b4 ). The contact detection means 129 outputs pattern signals "6", "1", "5", "3" corresponding to these contact attitude patterns, for example. The contact detection means 129 outputs the pattern signal "0" by regarding the other patterns as the floating state.

In the vertical movement mode attitude calculating means 131a, according to the output of the contact detecting means 129,

[Equation 5] Is calculated. That is, the output of the contact detection means 129 is 6
In the case of z _a1 is assigned to z _a, z _b1 is assigned to z _b.
Here, z ₀ is the average value of the levitation gap lengths of the magnet units 60a and 60b in the predetermined levitation state. When the output of the contact detection unit 129 of the pattern signal "1", z _a2 to z _a is, z _b2 is assigned to z _b, is z _a3 in z _a in the case of signal "5", z _b Is assigned to z _b3 . When the output of the contact detection means 129 is the pattern signal "3", z _a
Z _a4 is, the vertical deviation Delta] z ₀ at the time of contact based on the output of the z _b4 assignment has been contact detection unit 129 to z _b are calculated. Similarly, in the pitch mode attitude calculation means 131b, l _ξ
Is the distance between the centers of the magnet units 60a, 60b

[Equation 6] Thus, the pitch deviation Δξ ₀ at the time of contact is calculated based on the output of the contact detection means 129.

The vertical movement mode attitude estimation means 127a is configured as shown in FIG. 9 together with the vertical movement mode initial value setting means 133a and the vertical movement mode estimation initialization means 135a. That is, in order to realize the observer in the up / down mode, the up / down motion mode attitude estimating means 127a includes the gain compensators 141, 143, 145 which receive the output Δi _z of the exciting current deviation coordinate conversion circuit 125, and the integrator 14.
7, 149 and 151, a gain compensator 153 that inputs the output of the integrator 147, gain compensators 155 and 157 that inputs the output of the integrator 149, and a gain compensator 159 that inputs the output of the integrator 151. 161, 163, a gain compensator 165 which receives the output e _z of the vertical movement mode control voltage calculation circuit 137a as an input, and gain compensators 141, 15
5, 159, and an adder 167 that outputs the input to the integrator 147 and gain compensators 143, 153.
An adder 169 for adding the outputs of 161 and outputting the input to the integrator 149, and gain compensators 145, 157, 16
Adders 171 that add the outputs of 3, 165 and output the inputs to the integrator 151, and the integrators 147, 149, and 15
1, initial value setting (not shown) associated with each of the above-mentioned 1 and estimation initialization means (not shown) also associated with each of the integrators 147, 149, 151, and the gain compensator 15.
A limiter 184 as an estimated output limiting means for limiting the output of the integrator 147 after branching to 7 within the range of a predetermined value.

Each of the integrators 147, 149 and 151 has the same structure. For example, the integrator 147 and its associated initial value setting means and estimated initialization means are configured as shown in FIG. That is, the integrator 147 including the resistor 185 to which the output of the adder 167 is input, the capacitor 187, and the operational amplifier (operational amplifier) 189 includes the relay unit 191 that short-circuits the capacitor 187. When the output of the contact detection means 129 becomes non-zero due to the detection of the contact, the relay unit 191 operates to short-circuit the capacitor 187, and the integration result of the integrator 147 is reset to zero.
In the present embodiment, the relay unit 191 which is short-circuited by the contact detection of the contact detection unit 129 constitutes the vertical motion mode estimation initialization unit 135 ′. On the other hand, the output of the integrator 147 is connected to the resistor 193. This resistor 193, an initial value voltage generator 195 for generating a voltage corresponding to the Delta] z ₀ enter the Delta] z ₀ to the output of the vertical movement mode posture calculating means 131a by the contact detection of the contact detection unit 129, an initial value voltage generator Resistor 197 connected to 195 and resistor 19
9, 201 and the operational amplifier 203 constitute an initial value setting means 133 ′ in the vertical movement mode. Other integrator 14
Although 9 and 151 have the same configuration, the initial value voltage generator 195 associated therewith outputs zero as an initial value corresponding to the integrators 149 and 151. These three integrators 1
The estimation initialization means and the initial value setting means 133 ′ associated with 47, 149 and 151 collectively constitute the vertical movement mode estimation initialization means 135a and the vertical movement mode initial value setting means 133a, which are differentially configured. Operational amplifier 2
The output of 03 becomes the output of each integrator 147, 149, 151. That is, the estimated values of the vertical deviation Δz, the speed d (Δz) / dt, and the exciting current deviation Δi _z , which are the estimation results of the vertical movement mode attitude estimation means 127a, are output.

The pitch mode attitude estimating means 127b, the pitch mode initial value setting means 133b and the vertical movement mode estimating initialization means 135b are similarly constructed as shown in FIGS. 9 and 10. For simplification, the corresponding input / output signal is indicated by a signal name and its description is omitted. However, in the pitch mode, the initial value voltage generator 19 associated with the integrator 147 is
Reference numeral 5 is Δξ output from the pitch mode attitude calculation means 127b.
_{It is configured} to input ₀ and generate a voltage corresponding to the Δξ ₀ . Pitch mode integrators 147, 14
The estimated values of the pitch deviation Δξ, its speed d (Δξ) / dt and the exciting current deviation Δi _ξ , which are the estimation results of the pitch mode attitude estimation means 127b, are output from 9, 151.

The vertical motion mode control voltage calculation circuit 137a is constructed as shown in FIG. 11, for example. That is,
A gain compensator 20 for multiplying an estimated value of the vertical deviation Δz, its speed d (Δz) / dt and Δi _{z by} an appropriate feedback gain.
5, a current deviation target value generator 207, and a subtracter 209 for subtracting Δi _z from the target value of the current deviation target value generator 207
And an integral compensator 211 for integrating the output value of the subtractor 209 and multiplying it by an appropriate feedback gain, and a gain compensator 2
The output of the adder 213 for calculating the sum of the output values of 05 and the input of the output of the integration compensator 211 output a value equal to the input within a predetermined range, and when the input exceeds the upper limit of the same range, the upper limit is output. An integral output limiting means 215 that outputs a value and outputs a lower limit when the value is below the lower limit, and an adder 2
Subtract the output value of 13 from the output value of the output limiting means 215
Subtractor 217 that outputs the z-mode electromagnet excitation voltage e _z
And a limiter 218 as voltage output limiting means for limiting the output of the subtractor 217 within a range of a predetermined value.

The pitch mode control voltage calculation circuit 137b is also configured in the same manner as the vertical movement mode control voltage calculation circuit 137a, and the corresponding input / output signals are indicated by signal names, and description thereof will be omitted.

Next, the operation of the partition body supporting device according to the first embodiment having the above-described structure will be described.

When the device is stopped, the magnet unit is
The tips of the iron cores 68 (68 ') of the guts 60a and 60b are piezoelectric.
It is attached to the lower surface of the guide rail 44 via the rubber 73.
It When the device is activated in this state, the control device 70
And the contact detection means 129 is operated by the function of the piezoelectric rubber 73.
A pattern is detected by detecting the contact of the partition body 54 with the upper support member 46.
A posture signal calculating means 127a, 12 outputs a warning signal "6".
In 7b, the gap length of the magnet unit 60a is z_a1,magnet
The gap length of the unit 60a is z_b1Based on
Then, according to equation (10) and equation (11)
Initial estimated difference Δz ₀And ξ mode Pitch deviation estimated initial value
Δξ₀Is calculated. Posture estimation means 127 for each mode
a, 127b, the initial value setting means 133a, 133b
The estimated initial value is set more. At this time, the estimated initialization hand
In the steps 135a and 135b, the output of the contact detection means 129 is
Since it is not zero, the relay unit 191 turns on and the integrator
147, 149, 151 are short-circuited and the integration result is cleared
Then, the posture estimation means 127a and 127b are initialized.
It This causes the initial value setting means 133a to work.
The vertical deviation Δz output from the posture estimation means 127a,
Velocity d (Δz) / dt and Δi_zThe estimated values of Δz are₀，
0, 0, posture estimation hand by the action of the initial value setting means 133b
Pitch deviation Δξ output from the stage 127b, its speed d
(Δξ) / dt and excitation current deviation Δi_ξThe estimated values of
Δξ₀, 0, 0.

Control voltage calculation circuits 137a, 1 for each mode
When the estimation results of the posture estimating means 127a and 127b are input, the 37b calculates exciting voltages e _z and e _ξ that make the vertical deviation Δz ₀ and the pitch deviation Δξ ₀ zero. In the control voltage coordinate reverse conversion circuit 139, the control voltage calculation circuits 137a, 13
In response to the calculation result of the excitation voltage of 7b, the coils 69a and 69b
Of the excitation voltage e _a , e _b of the power amplifier 113a,
The attraction force of the magnet units 60a and 60b is controlled via 113b. In this state, the control device 70 controls the permanent magnet 6
The magnetic flux generated in the opposite direction to the magnetic flux generated by
The current generated in 6'is controlled in order to maintain a predetermined air gap length between the magnet units 60a, 60b and the guide rail 44 in the coils 69a, 69b. As a result, the partition body 54 separates from the lower surface of the guide rail 44 and shifts to the floating state. When the partition body 54 shifts to the floating state, the contact detection means 129 outputs 0, whereby the relay unit 191 is turned off in the estimation initialization means 135a, 135b, and the integrators 147, 149, 151 start the integration operation. To do. At this time, the initial value setting means 133a, 1
In 33b, since the contact detection means 129 outputs 0, the output value at the time of the last contact is maintained. As a result, in the flying start state, the posture estimation means 127a sets the initial value (Δ
z ₀ , ₀ , 0), and the posture estimation means 127b sets the initial value to (Δξ
_The estimation starts as ₀ , ₀ , 0). Posture estimation means 12
According to the equation (8), the estimation errors of 7a and 127b decrease rapidly with the passage of time as the error of the initial value decreases.

In the present embodiment, since the vertical deviation and the pitch deviation at the start of ascent coincide with the estimated initial value, the error at the start of estimation becomes small, and the estimated value rapidly converges to the actual value. Although the posture of the partition body 54 is limited by the upper support member 46 and the lower support member 52, the upper and lower limit values of the vertical deviation and the pitch deviation are set as the saturation range in the limiter 184, and the estimated value is the actual value. Attitude transition means 127a and 127b do not output an abnormal value during the transition period until the value converges. Therefore, the excitation voltage of each mode calculated by the control voltage calculation circuits 137a and 137b
The e _z and e _ξ also do not become abnormal values, and the control voltage coordinate reverse conversion circuit 139 uses the control voltage calculation circuits 137 a and 137.
b of the exciting voltage calculation result received by coils 69a, 69b of the exciting voltage e _a, e _b are calculated, a power amplifier 113a, 1
The attraction force of the magnet units 60a and 60b is controlled without abnormality via 13b.

If the attraction force control is performed without any abnormality at the start of floating in this way, as shown in FIG.
4 → iron core 68 → air gap G → guide rail 44 → air gap G '→ iron core 68' → magnetic circuit Mc consisting of the path of permanent magnet 64 is stabilized, and the gap length in air gaps G and G'is permanent magnet 3
The magnetic attraction force of each magnet unit 60a, 60b due to the magnetomotive force of 4 acts on the center of gravity of the partition 54 in the z-axis direction gravity, y
The length is just to balance with the torque around the axis. When an external force acts on the partition body 54 to maintain this balance, the control device 70 controls the excitation voltage of the electromagnets 66a and 66b ', and so-called zero power control is performed.

Here, a case will be described in which the magnetic levitation device 10 according to the present embodiment is used to form the sliding door shown in FIG. This sliding door is composed of a magnetic levitation device attached to the opening of the wall surface 220, and the guide rail 44 is slightly inclined toward the left end of the opening and toward the wall surface 220 (in the x direction and the y direction). The partition body 54 attached and supported in a non-contact manner by zero power control is in a state in which the door is closed without applying any external force. In this state, there are portions A, B and C where the magnetic material is projected on the facing surface of the guide rail 44 where the magnet units 60a and 60b face each other.
At 0b, the suction force to this portion acts as a mooring force.
For this reason, the partition body 54 does not open due to a slight sway of the wind or the building. Now, when opening this door, when a force in the x direction is applied to the partition body 54, the guide wheels 88, 88 'will move into the groove 50.
Since the guide shoe 86 moves along the upper guide groove 56 along the straight line part of the partition 54 which is not contact-supported.
Will move lightly and smoothly to open the door. The opened door slides along the inclination of the guide rail 44, and the door again assumes a closed state. On the other hand, when the closed door is pushed in the y direction, the guide wheel 88 moves along the curved portion of the groove 50, so that the partition body 54 attaches the axle 93 of the guide wheel 88 ′ and the support rod 84 of the guide shoe 86. Start rotation as the center. At this time, needless to say, the axles 93 and the support rod 84 have their respective axial centers aligned with each other. The partition 54 that started to rotate is a straight line L1 drawn between the two axles 93.
~ Move in the x direction while sequentially shifting to the posture represented by L7. That is, in the magnetic levitation device according to the present embodiment, the weight of the partition body is supported in a non-contact manner to significantly reduce the operating force of the door and the noise during opening and closing, and the partition body has a smooth two-dimensional shape. It is possible to give movement,
Even when the sliding door is opened from the wheelchair, the sliding door can be easily opened by pushing the door, and the operability and operation feeling can be significantly improved.

When the partition body 54 is supported in a non-contact manner, the guide wheels 88, 88 'and the guide shoe 86 are fitted in the groove 50 and the upper guide groove 56, respectively, and therefore an excessive horizontal external force is applied. On the other hand, the partition body 54 does not fall down.

On the other hand, even if the partition body 54 comes into contact with the upper support member 46 or the lower support member 52 due to an excessive disturbance, the contact of the partition body 54 with the magnetic levitation device of the present invention is performed. The attitude from time to time is detected by the contact detection means 129, and the attitude calculation means 131 and the initial value setting means 1 are detected.
Due to the actions of 33 and the estimation initialization means 135, the posture estimation means 127 outputs a normal estimation value. For this reason,
The partition body 54 returns to the floating state without any trouble.

Here, the partition body 5 is further affected by an excessive disturbance.
When 4 collides with the upper support member 46 or the lower support member 52, the estimated value of the posture estimation means 127 changes abruptly. Due to such a rapid change, the speed estimation value of the vertical deviation and the speed estimation value of the pitch deviation also change abruptly. Then, the control voltage calculation circuit 137 for each mode
Excitation voltage exceeding the capability of the power supply device 72 is output from a and 137b. In this case, the posture estimating means 127a, 12
The excitation voltages e _z and e ξ input to 7b are different from the mode-specific excitation voltage values actually obtained from e _a and e _b . Then, the posture estimation means 127a and 127b cannot perform normal posture estimation, and it becomes difficult to stabilize the floating state. However, in the magnetic levitation device 10 according to the present embodiment, the excitation voltage calculation unit 13
The vertical movement mode control voltage arithmetic circuit 137a and the pitch mode control voltage arithmetic circuit 137b of No. 6 have limiters 218 as the respective voltage output limiting means. A voltage value in each mode related to the capacity limit of the power supply device 72 is set as a saturation value in the limiter 218, and the excitation voltages e _z and e input to the posture estimation means 127 a and 127 b are set.
_ξ does not actually differ from the value of the mode-specific excitation voltage obtained from e _a and e _b . For this reason, the partition body 54 may be further disturbed by the upper support member 46 or the lower support member 5 due to an excessive disturbance.
Even if the vehicle collides with the position 2, the posture estimating means 127a and 127b operate without any trouble, and the partition body 54 returns to the floating state again. As described above, the magnetic levitation device according to the present invention can greatly improve the reliability of the levitation state.

As shown in FIGS. 4 and 12, when the guide rail 44 has a branch point, the conventional magnetic levitation device having a gap sensor has a principle of detecting the sensor arranged along the trajectory of the gap sensor. A sensor target made of a suitable material was required, but since the magnetic levitation device of the present invention does not require a gap sensor, the sensor target can be omitted, and the device can be simplified and the cost can be reduced. You can

Thus, when stopping the magnetic levitation 10 which has maintained a stable levitation state, for example, the current target value of the z-mode current target value generator 207 can be changed from zero to a predetermined negative value. The partition 54 is attracted to the upper support member 46. The operation of the power supply device 72 can be stopped by turning off a switch (not shown) of the power supply device 72.

<Second Embodiment> Next, the second embodiment of the present invention will be described.
The embodiment will be described with reference to FIG. In the first embodiment, the magnet unit was attached to the levitation body side, but this does not limit the attachment position of the magnet unit at all, and the magnet unit is arranged on the ground side as shown in FIG. May be. Note that, for simplification of description, the same parts as those of the first embodiment will be described below by using the same reference numerals.

The magnetic levitation device 300 has a U-shaped cross section and is formed of a non-magnetic material such as an aluminum member. The auxiliary supporting means 302 installed on the ground and the auxiliary supporting means 302.
Magnet unit 60 mounted downward on the upper bottom surface of the
And a guide 304 formed of a ferromagnetic member having a U-shaped cross section facing the magnet unit 60, for example, iron, and a vibration isolation table 306 having the guide 304 on the upper surface of the bottom and formed in a U shape as a whole. , A linear guide 30 attached to the side surface of the anti-vibration table 306 to give the anti-vibration table 306 a freedom of movement only in a direction vertical to the ground.
8 and the attraction force control means 15 for controlling the attraction force of the magnet unit 60 to support the anti-vibration table in a non-contact manner.

The suction force control means 15 is the auxiliary support means 30.
The contact detection means 314 provided with the micro switch 310 attached to the upper surface of the bottom of the second unit 2 and the piezoelectric rubber 312 stretched on the magnetic pole surface of the magnet unit 60, and the vibration isolation table 306 from the contact detection signal of the contact detection means 314. Table 30
6 or the attitude calculation means 35 for calculating the flying gap length when contacting the magnet unit 60, the current sensor 23 for detecting the exciting current of the magnet unit 60, and the magnet unit 60.
Posture estimating means 25 for estimating the floating posture of the vibration isolation table 306 from the exciting current and exciting voltage, and an initial value setting means 39 for setting an estimated initial value in the posture estimating means 33 based on the output of the posture calculating means 35. , An estimation initialization unit 13 that initializes the posture estimation unit 25 based on the output of the contact detection unit 314, and a magnet unit 6 that magnetically levitates the vibration isolation table 306 based on the output of the posture estimation unit 25.
An excitation voltage calculation unit 25 that calculates the excitation voltage to 0 and a power amplifier 113 that is connected to a power source (not shown) that excites the magnet unit 60 based on the output of the excitation voltage 25 are provided.

By arranging the magnet units in this way, there is an advantage that the weight of the vibration isolation table can be reduced by the amount of the magnet units.

<Third Embodiment> A third embodiment of the present invention will be described with reference to FIG. In the above-described first and second embodiments, the same-dimensional state observer is used as the attitude estimating means, but this does not limit the configuration of the attitude estimating means at all, and is within the scope of the present invention. Any estimation means will do as long as it is used. For example, the configuration may be such that the minimum dimension observer shown in FIG. 14 is used.

For example, in the magnetic levitation apparatus 300 shown in FIG. 13, the posture estimating means 400 composed of the minimum dimension observer of the following equation can be used. That is,

[Equation 7] Where z _ob is the state vector of the observer, α ₁ and α ₂ are the parameters that determine the poles of the observer, and y = Δi _z
Is.

The posture estimating means 400 includes gain compensators 402, 404, 406 and 407 having Δi _z as inputs, integrators 408 and 410, a gain compensator 412 having an output from the integrator 408, and an integrator. The gain compensators 414 and 416 that receive the output of 410, the gain compensators 418 and 420 that receive the output e _z of the excitation voltage calculation unit 324, and the outputs of the gain compensators 404, 406, and 414 are added and integrated. An adder 422 that outputs the input to the integrator 408, an adder 424 that adds the outputs of the gain compensators 412, 416, 418, and 420 and outputs the input to the integrator 410, a gain compensator 402, and an integrator. An adder 426 that adds the output of 408, and an adder 4 that adds the outputs of gain compensator 407 and integrator 410 and outputs an estimated value of speed d (Δz) / dt
28, and a limiter 430 as an estimated output limiting unit that limits the output of the adder 426 within a range of a predetermined value. It goes without saying that the output of the limiter 430 is an estimated value of the vertical deviation Δz.

Further, the attitude calculating means 400 is provided with a switching means 432 at the input end of Δi _z . Switching means 43
While the contact detecting unit 314 in 2 has detected the contact switch the .DELTA.i _z which has been input so far to zero, the contact has a becomes undetected function of switching the zero .DELTA.i _z. When the minimum dimension observer is used as the attitude estimation means, Δi _z is directly output as an estimated value of the vertical deviation Δz via the gain compensator 402 → adder 426 → limiter 430, so the integrator 408 set at the time of contact is set.
Α ₁ Δi _z is added to the posture information of the image stabilization table 306 at the time of contact. Then, the estimated value of the vertical deviation Δz of the attitude calculation means 400 becomes different from the actual value, which hinders the movement of the image stabilization table 306 to the floating state. In this case, due to the action of the switching means 432, α ₁ Δi _z is not added to the posture information of the image stabilization table 306 at the time of contact, and the output of the posture calculating means 400 becomes close to the actual value. In this case, the vibration isolation table 306 does not hinder the transition to the floating state, and the reliability is improved. In the present embodiment, the switching means 432 is provided at the input end of Δi _z , but this is means for bringing the estimated value of the attitude estimation means at the time of contact close to the actual value, and depending on the configuration of the attitude estimation means e _The switching means 432 may be provided at the input end of _z without any problem. In the present embodiment, the minimum dimension observer is applied to the posture calculation means, but in this case, there is an advantage that the number of integrators can be reduced.

<Modification> In each of the above embodiments, the control device for performing magnetic levitation control is described as if it is an analog type, but the control device of the present invention is not limited to the analog type. Instead, it can be implemented by a digital type.

Further, in each of the above-mentioned embodiments, the voltage type power amplifier is used, but this does not limit the power amplifier system at all, and may be the PWM type power amplifier, for example. .

In addition, in each of the above-mentioned embodiments, the U-shaped magnet unit is used, but this does not limit the shape of the magnet unit at all, and is, for example, E-shaped. good.

Furthermore, in each of the above embodiments, a permanent magnet is used as the magnet unit, but this does not limit the structure of the magnet unit at all, and the magnet unit is composed of only electromagnets without a permanent magnet. You may.

Although a voltage type power amplifier is used as the power amplifier, this does not limit the electromagnet driving system of the driver at all, and may be, for example, a PWM type. Besides the above, various modifications can be made without departing from the scope of the present invention.

[0078]

According to the magnetic levitation device of the present invention, information on the gap length and its speed can be estimated from the exciting current of the magnet unit, and magnetic levitation without the gap sensor is possible. Therefore, not only the cost of the gap sensor is reduced, but also the sensor target is not required, and the cost of the entire system can be reduced by simplifying the device.

Further, since the linear control theory can be applied, the robust stability of the floating state can be ensured and the reliability of the device can be improved as compared with the conventional sensorless magnetic levitation system.

[Brief description of drawings]

FIG. 1 is a configuration diagram for explaining the principle of the present invention.

FIG. 2 is another configuration diagram for explaining the principle of the present invention.

FIG. 3 is a perspective view showing the overall configuration of a first embodiment of a magnetic levitation device according to the present invention.

FIG. 4 is a plan view of the embodiment of FIG.

5 is a front view of the embodiment of FIG.

6 is an elevational view of the embodiment of FIG.

FIG. 7 is an elevation view of the magnet unit according to the embodiment of FIG.

FIG. 8 is a block diagram showing an internal configuration of a control device in the embodiment of FIG.

9 is a block diagram showing a detailed configuration of a posture estimation unit in the control device in the embodiment of FIG.

FIG. 10 is a circuit diagram showing a configuration around an integrator of the posture estimation means in the embodiment of FIG.

11 is a circuit diagram showing a detailed configuration of a control voltage calculation circuit in the control device according to the embodiment of FIG.

FIG. 12 is a plan view for explaining the operation of the partition body in the embodiment of FIG.

FIG. 13 is a block configuration diagram showing an overall configuration of a second embodiment of a magnetic levitation device according to the present invention.

FIG. 14 is a block diagram showing the configuration of a posture estimating means in a third embodiment of the magnetic levitation device according to the present invention.

[Explanation of symbols]

1, 1 ', 40, 300 Magnetic levitation device 3, 64 Permanent magnets 5, 66, 66' Electromagnets 7, 60, 60a, 60b Magnet unit 9 Load weight 11 Levitating body 13, 304 Guide 15 Suction force control means 17a, 17b Yoke irons 19a, 19b, 69, 69 ', 69a, 69b Coil 21 Gap sensor 23 Current sensor 25, 324 Excitation voltage calculator 27 Driver 28, 73a, 73b, 312 Piezoelectric rubber 29, 129, 314 Contact detection means 31, 302 Auxiliary support means 33, 127a, 127b, 318, 400 Posture estimation means 35, 131a, 131b, 316 Posture calculation means 37, 135a, 135b, 322 Presumption initialization means 39, 133a, 133b, 320 Initial value setting means 42 Ceiling 44 Guide rail 45 Plane correction member 46 Upper support member 48 Floor 50 Groove 5 Lower support member 54 Partition 56 Upper guide groove 62, 62 'Base plate 68, 68' Iron core 70 Control device 72 Power supply device 80 Frame part 82 Partition plate 83 Fixed base 84 Support rod 86 Guide shoe 88, 88 'Guide wheel 89 Guard Member 91 Side frame 93 Axle 95 95 Bottom frame 97 Cushion member 101 Upper base 103 Lower base 104 Side plate 105 Upper frame 107 Cover 111 Sensor unit 112 Arithmetic circuit 113, 113a, 113b Power amplifier 114 Cooling fins 121a, 121b Current detector 123a , 123b, 209, 217 Subtractor 125 Excitation current deviation coordinate conversion circuit 127a Vertical movement mode attitude estimation means 127b Pitch mode attitude estimation means 136 Control voltage calculation unit 137a Vertical movement mode control voltage calculation circuit 137b Pitch mode control voltage calculation circuit 13 9 Control voltage coordinate reverse conversion circuits 141, 143, 145, 153, 155, 157, 1
59, 161, 163, 205, 402, 404, 40
6,407,412 Gain compensators 147,149,151,408,410 Integral compensators 167,169,171,213,422,424,4
26, 428 Adder 184, 218, 430 Limiter 185, 193, 197, 199, 201 Resistor 187 Capacitor 189, 203 Operational amplifier (operational amplifier) 191 Relay unit 195 Initial value voltage generator 207 Current target value generator 215 Output limiting means 220 Wall surface 306 Anti-vibration table 308 Linear guide 310 Micro switch

Claims (18)

[Claims] 1. A magnet unit provided with an electromagnet, a levitation body supported by the magnet unit, magnetic poles of the magnet unit facing each other with a gap therebetween, and the levitation body is made non-movable by an attractive force exerted by the magnet unit. A ferromagnetic member for supporting by contact, an auxiliary supporting means for maintaining a positional relationship between the levitation body and the ferromagnetic member when the levitation body is not in a floating state, and a sensor section for detecting an exciting current of the electromagnet. Attitude estimation means for estimating the attitude of the floating body with respect to the ferromagnetic member based on the output of the sensor unit, contact detection means for detecting contact between the floating body and the ferromagnetic member or the auxiliary support means, Attitude calculation means for calculating the attitude of the floating body with respect to the ferromagnetic member at the time of contact based on the output of the contact detection means, and at the time of contact based on the output of the contact detection means Estimating initialization means for initializing to a state at the time of starting operation, initial value setting means for setting an output value of the posture calculating means as an initial value of the posture estimating means when the posture estimating means is initialized, and posture An attraction force control having a driving means for controlling the attraction force of the magnet unit so that the magnetic circuit formed by the magnet unit via the air gap and the ferromagnetic member is stabilized based on the output of the estimation means. A magnetic levitation device comprising: 2. The magnetic levitation apparatus according to claim 1, wherein the magnet unit includes a permanent magnet arranged so as to share a magnetic path with a magnetic flux of the electromagnet in the air gap. 3. The attraction force control means includes zero power control means for stabilizing the magnetic circuit while converging the exciting current of the electromagnet to zero based on the output of the sensor section. The magnetic levitation device according to claim 2. 4. The magnetic levitation apparatus according to claim 3, wherein the zero power control means is constituted by the attitude estimation means. 5. The attitude estimating means estimates the attitude of the levitation body with respect to the ferromagnetic member and the time change of the attitude based on an exciting current of the electromagnet and an exciting voltage generating the exciting current. The magnetic levitation device according to claim 1. 6. The posture estimating means inputs the output of the posture estimating means, outputs the input value as it is when the input is within a predetermined saturation range, and saturates when the input is outside the predetermined saturation range. The magnetic levitation apparatus according to claim 1, further comprising an estimated output limiting unit that outputs a value. 7. The attraction force control means is provided with an excitation voltage calculation section for calculating an electromagnet excitation voltage based on the output of the estimated output limiting means and giving the output to the drive means. The magnetic levitation device according to claim 1. 8. The excitation voltage calculation unit inputs the output of the excitation voltage calculation unit, and when the input is within a predetermined saturation range, the input value is input, and when the input is outside the predetermined saturation range, a saturation value is input. The magnetic levitation device according to claim 7, further comprising a voltage output limiting unit that outputs 9. The excitation voltage calculation unit is represented by a linear combination of the electromagnet excitation voltages so as to generate an attractive force that contributes to the degree of freedom of movement of the levitation body, based on the output of the estimated output limiting means. The magnetic levitation apparatus according to claim 7, further comprising a mode excitation voltage calculation unit that calculates the excitation voltage for each mode. 10. A mode exciting current calculator for calculating the current for each mode represented by a linear combination of the exciting currents of the electromagnets for generating an attractive force that contributes to the freedom of movement of the floating body. The magnetic levitation device according to claim 9, further comprising: 11. The magnetic levitation apparatus according to claim 9, wherein the mode excitation voltage calculation unit includes the voltage output limiting means that receives an output of the mode excitation voltage calculation unit as an input. 12. The attitude estimating means calculates the attitude of the levitation body with respect to the ferromagnetic member and the time of the attitude based on the output of the mode-specific exciting current calculator and the output of the mode exciting voltage calculator of the electromagnet. The magnetic levitation device according to claim 10, wherein the change is estimated. 13. The posture estimating means has an integrator, and when the contact detecting means detects a contact, the estimation initialization means stops the integration of the integrator and the integration result is the initial value. When the contact detection means stops detecting contact, the value output by the initial value setting means at the time of the contact immediately before that becomes the initial value, and the estimation initialization means sets the value of the integrator. The magnetic levitation device according to claim 1, wherein integration is started. 14. The posture estimating means switches to zero input the exciting current of the electromagnet and the output of the exciting voltage calculating section which are inputted to the posture estimating means when the contact detecting means detects a contact. 8. The magnetic levitation apparatus according to claim 7, further comprising switching means for switching the zero input to the exciting current of the electromagnet or the output of the exciting voltage computing section when the contact detecting means stops detecting contact. 15. The posture estimating means outputs zero output of the mode exciting current calculating section and the mode exciting voltage calculating section which are input to the posture estimating means when the contact detecting means detects a contact. 10. The switching means according to claim 9, further comprising a switching means for switching to an input and switching a zero input to an output of the mode excitation current calculation section or the excitation voltage calculation section when the contact detection section stops detecting a contact. Magnetic levitation device. 16. The magnetic levitation apparatus according to claim 1, wherein the auxiliary supporting means is associated with the levitation body. 17. The magnetic levitation apparatus according to claim 1, wherein the auxiliary supporting means is associated with the ferromagnetic member. 18. The magnetic levitation apparatus according to claim 1, wherein the magnet unit is attached to the levitation body.