CN103227607B - The method controlling linear electric motors - Google Patents

Abstract

A kind of for drive have make a long driver dynamic stroke heavy duty machine tools axle linear electric motors in, pole position correction value on multiple stroke positions stores in memory.Pole position correction value based on storage calculates the pole position correction value corresponding to the actual stroke position of slider.The correction electrical angle deviant calculated based on the pole position correction value calculated is used to control linear electric motors.

Description

The method controlling linear electric motors

Priority information

This application claims with filing date January 26, the Japanese patent application of Application No. 2012-013669 in 2012, and filing date on October 5th, 2012, the Japanese patent application of Application No. 2012-223520 are priority, the full content of the two application is hereby incorporated by reference the application.

Technical field

The present invention relates to the control to linear electric motors.

Background technology

In recent years, lathe axially driving in, a kind of directly driving is with the table top of motor (electrical motor, hereinafter referred to as " motor ") and does not use the method for ball-screw to put it into commercial operation.Linear electric motors are employed in such lathe.

In this driving method using linear electric motors, owing to not having deceleration member, such as ball-screw, therefore, the positioning precision of the slider of linear electric motors corresponds directly to the positioning precision of drive shaft.Therefore, for linear electric motors, the positioning precision that demand is high.Generally when using linear electric motors, high-resolution position detector can be installed, drive the position of target with detection.

Linear electric motors include the slider being arranged on mobile unit, such as table top, and the stator being arranged in fixed cell, such as bed body.According to different principle, there are various types of linear electric motors.Such as, JP 2007-318839 A describes a type of linear electric motors, and its stator used has and is arranged on the salient pole on opposed facing surface with preset space length.On the stator that straight-line extension is arranged, stator bearing of trend is provided with salient pole.On the slider that can move along the stator arranged in extension mode, it is provided with the magnetic pole facing to stator salient poles.Described magnetic pole is made up of coil and permanent magnet.When coil inputs predetermined power, stator bearing of trend defines shifting magnetic field, and due to the interaction between shifting magnetic field and salient pole, slider moves on the bearing of trend of stator.

It is described below a kind of typical method for controlling linear synchronous generator.Fig. 1 is the structural schematic block diagram of linear motor control device.This linear motor control device includes position detector 12, proportional amplifier 21 and 22, distributing switch 23, integral amplifier 24, current controller 25, differentiator 26, three-phase PWM inverter 28 and amperometric 29.In this control device, as input position instruction X, the difference between the detected value (it represents the position of slider) of position command value and position detector 12 is amplified by proportional amplifier 21, and the rate instruction V* as linear electric motors slider exports.Proportional amplifier 22 and integral amplifier 24 carry out PI calculating (differentiator 26 carries out differential to the detected value of position detector 12 and obtains this difference) to the difference between rate instruction V* and slider speed, produce thrust command F*.After receiving the thrust command F* of input, distributing switch 23 produces current instruction value Iu* and Iv* in three-phase current instruction Iu*, Iv* and Iw*, and exports these command value to current controller 25.In this process, when producing current-order, the direction value of position detector 12 be have also contemplated that into.

Based on current-order Iu* and Iv* inputted from distributing switch 23 and from relational equation Iu*+ The current-order Iw* derived in Iv*+Iw*=0, current controller 25 produces three-phase voltage instruction eu*, ev* and ew*, and exports these voltage instructions to three-phase PWM inverter 28.Instruct eu*, ev* and ew* based on three-phase voltage, drive linear electric motors by applying three-phase alternating voltage obtained by the DC voltage from DC source 27 is changed by inverter 28.Actually applied voltage on linear electric motors is that three-phase voltage instructs eu*, ev* and ew*, and ew* is that the difference of current detection value iu, iv and iw of being detected from amperometric 29 by current controller 25 determines.

In above-mentioned control method, maximum for the thrust making linear electric motors under same electric current, must be to apply electric current relative to optimum current phase angle for the position of stator salient poles of slider position, especially slider magnetic pole.

Phase angle described below as optimum current phase angle.Fig. 2 illustrates thrust when slider slides at constant current, produced by linear electric motors relative to stator.As can be seen from Figure 2, when current phase angle is 90 °, the thrust of linear electric motors is maximum.

In practical operation, the control device of linear electric motors applies electric current to pole coil, to reach the current phase angle of 90 °, and the slider position that monitoring position detector obtains simultaneously, i.e. the position of slider magnetic pole.In this process, for making control device apply electric current with accurate current phase angle, position detector, slider and stator must be installed on a predetermined position.If installation site offsets, then detector will be unable to accurately detect the position of slider magnetic pole, and electric current will deviate from optimum phase angle, and therefore thrust will reduce.

While it is true, in practice, due to the dimensional tolerance of parts and install the backlash of bolt and screw, linear electric motors and position detector can not be precisely mounted at precalculated position.Therefore, it is difficult for will applying electric current with optimum phase angle.

Hereinafter will be more particularly described.Assuming that have 360 ° of current phases mechanical phase (pitch) corresponding to 12mm of the linear electric motors of feature shown in Fig. 2.In this case, if the installation site of slider, stator and position detector 30 ° the most out of position (i.e. 1mm mechanical phase), as in figure 2 it is shown, then thrust will reduce 19% than the maximum thrust obtained when applying electric current with optimum phase angle.For the situation preventing this thrust from reducing, such as JP Disclosed in 2008-178237 A, it is proposed that a kind of position of magnetic pole bearing calibration, wherein, position of magnetic pole corrected value is stored in control device, the position of magnetic pole of electronic correction position detector.

In those heavy duty machine tools with the longest linear electric motors of its driving stroke, the stator being divided into some can be used.That is, can arrange according to length of stroke and be divided into multiple stator segment of each several part and form stator.Owing to each stator segment has length dimension error and alignment error, therefore generation is offset by the pitch of the stator salient poles between stator front end and rear end.In the position of magnetic pole bearing calibration of existing correlation technique, due to an only position of magnetic pole corrected value, it is accordingly dependent on the position of stator and creates the position that thrust reduces.

Hereinafter will be more particularly described.Assuming that in the linear electric motors shown in Fig. 2,360 ° of current phases correspond to the mechanical phase (pitch) of 12mm, and stator stroke is 9000mm, and is provided with the linear motor stator electric sections of 15 each a size of 600mm.In these cases, if the length dimension error of stator is 0.1mm, alignment error is 0.1mm, then relative to stroke center, the pitch skew of stator salient poles is 42 ° (or 1.4mm mechanical phases) to the maximum at stroke end.Therefore, if region whole to stroke all uses the position of magnetic pole corrected value determined at stroke center, as in figure 2 it is shown, then compared with the thrust obtained at stroke center, the thrust obtained at stroke end reduces 26%.

It is divided into manifold stator in addition to the structure with physical division, its manufacture process is also piecemeal is formed.Described stator is to carry out stacking and formed by side is formed steel disc that is recessed and that protrude, and projection becomes salient pole.It is processed into by carrying out punching press with the stamping machine there is corresponding female entering-protrude shape there is recessed-steel disc of protruding.When punching press, repeatedly processing, stamping machine carries out relative feeding relative to homogenous material simultaneously.Usually, stamping machine is fixing, and will be during repeatedly material is sequentially sent to machine.In punching press once after, by the size of material feeding stamping machine drift size, this position carries out second time punching press.Repeat these processes, to be processed into steel disc that length is more than stamping machine size, that there is recessed-protrusion.In the following description, in addition to the stationary part physically divided, the recessed and protrusion being stamped and formed out by single in stationary part is also referred to as " stator segment ".

The stator formed by one piece is carried out Multi-step forming has a structure in which that in multiple stator segment, each stator segment is corresponding to single punching press, and these stator segment are arranged along stator bearing of trend.In this case, also can arrange virtual stator segment, the pitch of stator salient poles can offset because of the position skew between stator segment or other similar factor.Such as, can due on the moving direction of material stamping machine scale error or add every time material in man-hour amount of movement error and produce salient pole position skew.

A benefit of the invention that, it is provided that a kind of control method alleviating thrust reduction in the whole length of stator.

Summary of the invention

According to an aspect of the invention, it is provided a kind of method for controlling linear electric motors, it corrects the position skew of stator salient poles according to the stroke position of slider, and drives based on the salient pole position after correction and control linear electric motors.Described stator is located along on the position that reservation shape extends.Described stator is generally configured as linear, but the most also can have the curved section being positioned at horizontal plane, or has the section tilted in the vertical direction.It is formed with recessed on stator in the setting direction of stator, i.e. bearing of trend and protrudes.These extensions that are recessed and that protrude are referred to as salient pole.Slider can move along stator bearing of trend.The female and protrusion are also formed on the slider facing with the recessed of stator and protrusion, to form magnetic pole.Such as, magnetic pole is to be formed by around the coil of slider extension and the permanent magnet that is positioned on the surface of this extension.When to coil input predetermined power, slider defines the magnetic field moved along stator bearing of trend.Described slider is moved by the interaction between shifting magnetic field and stator salient poles.Alternatively, described magnetic pole can be formed on stator, and described salient pole can be formed on slider.Described magnetic pole and salient pole are hereafter referred to collectively as " pole ".

In linear electric motors, the position of slider has two kinds.One is the position relevant with reciprocating motion when slider makes driven object reciprocating along stator (stroke).Another kind is the relative position between magnetic pole with salient pole.The former is equivalent to the mechanical angle of electric rotating machine, and the latter is equivalent to the electrical angle of electric rotating machine.Hereinafter, the position relevant with the reciprocating motion along stator is referred to as " stroke position ", and magnetic pole is referred to as " position, pole " with the relative position of salient pole.

As it has been described above, electric energy must apply with the phase place corresponding to position, slider pole.For realizing this purpose, it is provided with the position detector for detecting slider stroke position.It is desirable that owing to position, pole changes at a time interval relative to the change of slider stroke position, therefore, the position, pole of slider can be calculated easily by the stroke position of detection slider.Position detector includes the scale such as arranged along stator, and is set to the probe moved with slider integral type.When position of stator, especially salient pole position deviate described scale, the stroke position of the slider detected at position detector and offseting between the position (position of magnetic pole) of slider for stator physical location (salient pole position).That is, the relation between slider stroke position and position of magnetic pole there occurs skew.In the present invention, for each position in the multiple positions on stator bearing of trend, obtain in advance and store the corrected value for correcting offset, so that the position, slider pole determined by the stroke position of the slider detected to be corrected, and input electric energy based on closer to actual slider phase place.

The present invention explained below is for controlling a kind of concrete form of the method for linear electric motors.First, detection slider is along the stroke position of stator bearing of trend.Then, derive the pole position correction value at the stroke position that slider is detected based on pole position correction value, to correct the skew on stator bearing of trend of the stator poles position, and this value is prestored corresponding to the stroke position on stator bearing of trend.The position, pole of slider is calculated based on the stroke position detected by slider and the pole position correction value derived.Based on input electric energy in the coil that the position, pole calculating gained is arranged relative to position on stator or slider, drive linear electric motors with this.

According to a further aspect in the invention, stator can be formed by arranging multiple stator segment along stator bearing of trend, and prestore at least one pole position correction value for each stator segment.

According to a further aspect in the invention, multiple stator segment can be the section physically divided.Alternatively, stator segment can also be virtual stator segment.According to a further aspect in the invention, can by with stamping machine in one piece Multi-step forming and formed stator recessed-protrude shape.With after stamping machine for the first time punching press, material is a certain amount of relative to what stamping machine moved corresponding to stamping machine size, then carry out second time and process.Repeat these processes, to form long stator.The part that single is stamped and formed out is referred to as virtual stator segment.

According to a further aspect in the invention, for pole position correction value, the value at multiple stroke positions in a certain distance apart from one another can be stored, and the pole position correction value of section can be derived as equal to the pole position correction value in section one section between those stroke positions that its value stores.According to a further aspect of the invention, for pole position correction value, can store the value at those multiple stroke positions in a certain distance apart from one another, and the pole position correction value of the section between those stroke positions stored for its value can shift the meansigma methods into the pole position correction value on section two ends onto.

According to a further aspect in the invention, for pole position correction value, the value at those stroke positions in a certain distance apart from one another can be stored, store the pole position correction value of section between those stroke positions having value and can be derived as the value by obtaining in this section two linear insertion pole position correction value.

According to a further aspect in the invention, provide a kind of method calculating position, slider pole, this position, pole is the slider magnetic pole position about stator salient poles of linear electric motors, first obtaining on multiple positions of stator bearing of trend for correcting the stator salient poles position correction value in pole along the position skew of stator bearing of trend, and correspondence is along the value acquired in the position storage of stator bearing of trend.Then, when operating linear electric motors, detection slider is along the stroke position of stator bearing of trend.Further, the pole position correction value of the reading stroke position corresponding to being detected, and calculate the pole position correction value at detected stroke position.The position, pole of slider is calculated based on the stroke position detected and the pole position correction value that calculated.

Described stator can have a kind of structure, and plurality of stator segment is arranged along stator bearing of trend, and can obtain and store at least one pole position correction value of each stator segment.Multiple stator segment can be the section physically divided, or can be virtual stator segment.

Beneficial effect

By using the pole position correction value corresponding to slider stroke position, can prevent the thrust caused because of position of stator skew from reducing.

Accompanying drawing explanation

Fig. 1 is the structural schematic block diagram of linear motor control device；

Fig. 2 is the relation diagram of current phase angle and thrust in linear electric motors；

Fig. 3 is the structural schematic block diagram of the motor control assembly according to a preferred embodiment of the invention；

Fig. 4 illustrates the example of the linear electric motors with the stator formed by arranging multiple stator segment；

Fig. 5 is the relation diagram between the pole position correction value in the present invention and reasoning command value；

Fig. 6 is the present invention flow chart from the process getting driving of linear electric motors pole position correction value；

Fig. 7 A illustrates an example of relation between stroke position and pole position correction value；

Fig. 7 B show example of relation between stroke position and pole position correction value；

Fig. 7 C illustrates an example of relation between stroke position and pole position correction value；

Fig. 8 is the diagram of another example of linear electric motors, is provided with stator segment；

Fig. 9 illustrates between stroke position, needs to obtain an example of the pole position correction value interpolation method of the section of pole position correction value；

Figure 10 illustrates between stroke position, needs to obtain another example of the pole position correction value interpolation method of the section of pole position correction value；

Figure 11 illustrates between stroke position, needs to obtain another example of the pole position correction value interpolation method of the section of pole position correction value；

Figure 12 illustrates when each stator segment all obtains a pole position correction value, an example of the pole position correction value interpolation method in the range of stator segment.

Detailed description of the invention

Below with reference to accompanying drawing, a preferred embodiment of the present invention is described.Fig. 3 is the structural schematic block diagram of the motor control assembly according to a preferred embodiment of the invention.Fig. 6 is according to a preferred embodiment of the invention, from the flow chart getting driving process of linear electric motors pole position correction value.Fig. 9 to 12 illustrates the interpolation method of motor pole position correction value according to the preferred embodiment of the invention.

In figure 3, motor control assembly includes controller 40, and it has central processing unit (CPU) 42, memorizer 44 and position command and arranges unit 46.Described central processing unit 42 has and reads position correction program in pole from memorizer 44 and perform the function of this program.Described memorizer 44 is by the ROM being previously stored with pole position correction program and stores detection data in re-writable mode or the RAM etc. of class likelihood data is constituted.Position command arranges the function position command of slider of linear electric motors (this position command X be) that unit 46 has automatically or carrys out instruction X in setting position according to the manual operation of operator, and by position command X input proportional amplifier 21.Described position command arranges unit 46 can include input block, and such as switch, keyboard, dial or similar setting, for manual operation.Other structure of motor control assembly 1 is similar with the motor control assembly of Fig. 1, therefore uses the reference identical with Fig. 1, and does not repeats them here.

As it was previously stated, the electric energy of input linear electric motors slider must be to input about the phase angle of the position of salient pole (salient pole position) corresponding to magnetic pole.For realizing this purpose, it is provided with the position detector for detecting slider stroke position.This position detector includes the scale such as arranged along stator, and is set to the probe moved with slider integral type.Position relationship between detection starting point and the slider position of magnetic pole of position detector is to be determined relative to the installation site of slider by probe, and this position includes error certainly.For correcting this error, have employed the setting of a kind of deviant that may specify electrical angle.The electrical angle deviant being stored in advance in memorizer 44 by appointment, this error of recoverable, and the relation between the detection starting point of position detector and slider position of magnetic pole can be set as constant, do not affected by factors such as such as probe alignment errors.It addition, in the present embodiment, position correction value in pole is used to correct the position skew of stator salient poles and scale.By position correction value in pole is added in electrical angle deviant, slider magnetic pole can be mated relative to the position of stator salient poles relative to position and the slider magnetic pole of position detector scale.

Fig. 4 illustrates the structure of the pith of linear electric motors 11.The development length of stator 100 is L.Form the stator 100a of a pair and 100 arranged in parallel.Each stator 100a and 100b is band-shaped, is formed with recessed-protrusion shape on one side thereof, and those sides with recessed-protrusion are arranged with facing each other.Slider 101 is between two stator 100a and 100, and moves on the bearing of trend of stator 100.

Presently describe the structure of stator 100a and 100b.Hereinafter, will only describe one of them stator 100a, omit the description to other stator 100b.Stator 100a is to be formed by arranging, along stator bearing of trend, three stator segment 102A, 102B and 102C being physically separate from.When without distinguishing single stator segment, letter " A ", " B " and " C " will be omitted, and represent stator segment by reference " 102 ".Each length of three stator segment is L0 (=L/3).Alternatively, the quantity of the stator segment forming a stator can also be other quantity beyond 3.Alternatively, the length of multiple stator segment can be mutually different.

When by arranging multiple separate stator segment 102 and forming stator, side-play amount between slider position from position, pole can be different for each stator segment, it is specifically dependent upon the dimensional accuracy of single stator segment, and the installation accuracy etc. that stator segment is when fixing.

Can be by being formed recessed and protrude with stamping machine at the upper Multi-step forming of list (such as electromagnetic steel sheet) of a length of L, to manufacture stator 100a and 100b.It is piled up to form stator by the electromagnetic steel sheet after punching press.Stamping machine is fabricated to process the material in the range of length L0.When processing stator, first, the scope with stamping machine, the list of length L being corresponded to Fig. 4 left end stator segment 102A position carries out punching press.Then, corresponding for material stamping machine is moved to the left length L0(alternatively by this, and material can be fixing, and stamping machine can move right), stator segment 102B position carries out punching press.Repeat these operations, to form recessed-protrusion shape in whole length L of material.The part being once stamped and formed out is regarded as stator segment.

By making material move, simultaneously Multi-step forming and on the stator that formed, for each stator segment, the side-play amount between slider position from position, pole also can be different, and this is the precision by material displacement or similar reason causes.

Thrust command value in the present embodiment explained below and the relation between the pole position correction value obtaining pole position correction value.

Fig. 5 illustrates thrust command value F* when position correction value in pole changes.According to Fig. 5, when position correction value in pole is the optimal corrected value shown in Fig. 5, thrust command value is minimum；Along with pole position correction value because of the reduction of thrust that can produce under same current off-target corrected value, thrust command increases.Based on this, optimal pole position correction value can be obtained by the size of detection thrust command value F*.For utilizing this relation, linear electric motors must be set to constant thrust rating.

It is described below the set-up procedure of pole aligning method.Described pole method for correcting position can carry out software control by the central processing unit 42 in controller 40, or alternatively, a part for this step can be realized by hardware element.

In figure 6, first, in step S8, slider 101 is placed in the predetermined stroke position towards the first stator segment 102A.Then, in step S9, slider 101 is fixed up.Described fixing method can be to use mechanical brake to carry out limiting, using dynamo-electric brake to carry out limiting and use stationary fixture to carry out restriction etc..

Then, in step S10, send position command, point to the another location separated by a distance with current location.That is, by position command setup unit 46 automatically or be manually operated and in the position command X input proportional amplifier 21 that sets.In this process, linear electric motors are set as constant thrust state.

On the other hand, in the memorizer 44 of controller 40, it is previously stored with the electrical angle deviant for specifying the phase contrast between the detection starting point of position detector 12 and position, slider pole, and for correcting the pole position correction value of electrical angle deviant.Described pole position correction value is set as manually or automatically changing.

Then, in step S12, thrust command value F* of detection of straight lines motor, at subsequent step S14, thrust command value F* is compared with the threshold value preset.Threshold value can use value corresponding with position command X, that be stored in advance in memorizer 44.Alternatively, can set the threshold to such as thrust command value F* shown in Fig. 5 minima 5%.If thrust command value F* is more than or equal to this threshold value, change pole position correction value the most in step s 16, and step S12 with S14 detects thrust command value F* again and compared with threshold value.Repeat these operations, until thrust command value F* is less than threshold value.

When finding out the pole position correction value that thrust command value F* is set smaller than threshold value, in step S18, the detection position of this pole position correction value and position detector is stored in memorizer 44 as the detection position of pole position correction value and the first stator segment 102A.

After linear electric motors and position detector are arranged on lathe or other similar device, before linear electric motors are driven, step S8 to S19 can be performed.Subsequently, during relative position change between linear electric motors with position detector, such as linear electric motors or position detector are when being exchanged with each other, dismantle or be again coupled to etc., perform these steps.

It follows that in step S19, determine that the whole lengths of stroke for stator have the most all stored pole position correction value, if not storing pole position correction value for whole lengths of stroke, then repeat step S8 to S18.That is, slider 101 moves length L0 of stator segment, is placed in the stroke position in the face of the second stator segment 102B, performs step S9 and subsequent step, and the detection position of pole position correction value and the second stator segment 102B is stored in memorizer 44.Similarly, the detection position of pole position correction value and the 3rd stator segment 102C is stored in memorizer 44.

Repeat step S8 to S18 for length of stroke, and by position detector (or slider), position, i.e. stroke position are detected for whole strokes and the pole position correction value on this position is stored in memorizer 44.Fig. 7 A illustrates the corresponding relation between stroke position and pole position correction value.

In the foregoing description, slider 101 moves stator length L0, this is because need ideally to make the detection position in each stator segment be maintained at same position as far as possible, but only needing to locate corrected value for each stator segment and detect position, slider is without movable length L0.It addition, the position that the quantity of the position of position correction value and detection position to be determined is not limited in each stator segment, alternatively, multiple position can be used.Alternatively, the detection number of positions of each stator segment can change.Fig. 7 B show one example of this configuration.

Further, since each stator segment is carried out punching press by identical stamping machine, therefore, when the difference in length judging stator segment is the least, and when the alignment error of each stator segment is the least, it is not necessary to locate corrected value and detection position for whole stator segment.In this case, can be that the stator segment being positioned at two ends locates corrected value and detects position.Fig. 7 C illustrates an example of this configuration.

Fig. 8 illustrates another example structure of stator.In two stator 110a and 110b, mutually stagger a segment distance in the position of the stator segment of the stator segment of stator 110a and stator 110b, this distance equal to stator segment 112 arrangement pitch 1/2.Stator 110a is made up of stator segment 112A, 112B and 112C.Stator 110b is by stator segment 112A ', 112B ', 112C ' and 112D ' constitute.As shown in Figure 8, between the Boundary Moving of stator segment 112 stator 110a and 110b the 1/2 of pitch.

In this case, it is considered to the borderline virtual stator segment separated of stator segment 112 at two stator 110a and 110b.More specifically, two virtual sections 112A-1 and 112A-2 form stator segment 112A.Similarly, stator segment 112B and 112C are considered to be formed by virtual stator segment 112B-1,112B-2,112C-1 and 112C-2 respectively.Stator 110 is received through arranging six stator segment 112A-1,112A-2,112B-1,112B-2,112C-1 and 112C-2 are formed, and can measure the position correction value corresponding with six stator segment according to the similar mode of stator 100 shown in Fig. 4.

See Fig. 6, which show idiographic flow.Explained below correct, based on as the detection stroke position of position being stored in memorizer 44 and pole position correction value, the step that electrical angle offsets and controls motor.In step S20, controller 40 detects the current stroke position of slider 101, and in the step s 21, controller 40 measures pole position correction value δ for current stroke position.

Step S21 is described in detail below with reference to Fig. 9.

In fig .9, the relation between the stroke position and the pole position correction value at stroke position that are stored in memorizer 44 is assumed to shown in Fig. 7 A；That is, the pole position correction value at stroke position A is assumed to δ 1, and the pole position correction value at stroke position B is assumed to δ 2, and the pole position correction value at stroke position C is assumed to δ 3.In this case, pole position correction value changes with stroke position, so that the pole position correction value used by position between stroke position A and B is δ 1, pole position correction value used by position between stroke position B and C is δ 2 ... in the method, and pole position correction value is to be positioned at where according to slider 101 current stroke position in the stroke position that memorizer 44 stores to determine.

In step S22, the pole position correction value measured in step S21 is used to correct electrical angle deviant, i.e. coal addition position corrected value in electrical angle deviant, and in step S23, controller 40 inputs the electrical angle deviant adding Angle Position corrected value in distributing switch 23, is used for controlling motor.

As it has been described above, according to the present invention, can alleviate the scale error by stroke end stator length and thrust that alignment error is caused reduces.The thrust that can be shortened by pole position correction value assay intervals and alleviate between stroke position further reduces.

The diagram of the exemplary interpolative method on a certain section when Figure 10 is to obtain corrected value on multiple stroke positions in a certain distance apart from one another, between stroke position.The interpolation method of Figure 10 can determine the optimum of pole position correction value more accurately than method shown in Fig. 9.

The interpolation method of the pole position correction value shown in Figure 10 is in place of the difference shown in Fig. 9, uses on a certain section between predetermined stroke position the meansigma methods of adjacent correction value as pole position correction value.It is more fully described the method below with reference to Figure 10.

In Fig. 10, the pole position correction value at the stroke position A being stored in memorizer 44 is assumed to δ 1, and the pole position correction value at stroke position B is assumed to δ 2, and the pole position correction value at stroke position C is assumed to δ 3.In this embodiment, the pole position correction value used by stroke position is calculated by the meansigma methods measuring adjacent correction value, and correspond to stroke position and change, so that the pole position correction value that the section between stroke position A and B is used is meansigma methods δ 1 and δ 2, and the pole position correction value that the section between stroke position B and C is used is meansigma methods δ 2 and δ 3 ... in the method, determine current stroke position whereabouts in the stroke position that memorizer 44 is stored of detected slider 101, and pole based on stroke position position correction value and adjacent stroke position determine pole position correction value.Controller 40 inputs the electrical angle deviant that this pole position correction value is corrected in distributing switch 23, is used for controlling motor.

As it has been described above, according to the present invention, the thrust caused because of scale error and the alignment error of stroke end stator length can be alleviated and reduces.The thrust that the detection pitch that can be shortened by pole position correction value alleviates between stroke position further reduces.

Figure 11 is the diagram of the another exemplary interpolation method on a certain section when obtaining corrected value on multiple stroke positions in a certain distance apart from one another, between stroke position.The interpolation method of Figure 11 can determine the optimum of pole position correction value more accurately than method shown in Fig. 9.

The interpolation method of the pole position correction value shown in Figure 11 is in place of the difference shown in Fig. 9, uses the linear interpolation between adjacent correction value, using the pole position correction value used in a certain section between predetermined stroke position.It is more fully described the method below with reference to Figure 11.

In fig. 11, being stored in pole in memorizer 44, at stroke position A position correction value and be assumed to δ 1, the pole position correction value at stroke position B is assumed to δ 2, and the pole position correction value at stroke position C is assumed to δ 3.In this embodiment, by calculating between adjacent correction value, value after linear interpolation, thus correspond to stroke position and change the pole position correction value that used at certain stroke position, so, the pole position correction value used on section between stroke position A and B by inserting the value obtained in the linearly of δ 1 and δ 2, and the pole position correction value used on the section between stroke position B and C by inserting the value obtained in the linearly of δ 2 and δ 3 ... in the method, determine the location in the stroke position that memorizer 44 is stored, current stroke position that slider 101 detected, and insert pole position correction value based on the linearly at adjacent stroke position and the value that obtains determines pole position correction value.Controller 40 inputs the electrical angle deviant through the correction of this pole position correction value in distributing switch 23, to control motor.

As it has been described above, according to the present invention, the thrust because being caused in length dimension error and the alignment error of stroke end stator can be alleviated and reduces.The thrust that the detection pitch that can be shortened by pole position correction value alleviates between stroke position further reduces.

In Fig. 9 to the interpolation method shown in 11, when by arranging the stator forming linear electric motors corresponding to multiple stator segment of predetermined stroke length, the thrust caused because of scale error and the alignment error of stroke end stator length can be alleviated and reduce.In this case, need to measure the pole position correction value at least one position, place for each stator segment.For for the pole position correction value acquired in specific stator segment, such a can be used to configure: value identical in acquired pole position correction value can be used in the range of stator segment, and this value is not used in other stator segment.

In addition to Fig. 9 to the interpolation method shown in 11, the also interpolation method shown in Figure 12.Figure 12 illustrates when obtaining a pole position correction value for each stator segment, the exemplary interpolative method in the range of stator segment.In fig. 12, the pole position correction value at stator segment A is assumed to δ 1, and the pole position correction value at stator segment B is assumed to δ 2, and the pole position correction value at stator segment C is assumed to δ 3.In this embodiment, pole position correction value changes according to stator segment, so, the pole position correction value used in the range of stator segment A is δ 1, use pole position correction value in the range of stator segment B is δ 2 ... input the electrical angle deviant corrected through this corrected value, to control motor from controller 40 to distributing switch 23.

Although obtaining multiple pole position correction value for each stator segment, but, it is possible to for the interpolation method of each stator segment application Figure 10 and Figure 11, to occur thrust to reduce in the range of avoiding each stator segment.

When multiple sliders be placed on the bearing of trend of stator, i.e. in stroke direction time, the present invention can alleviate the reduction of linear electric motors with similar fashion.

More specifically, when arranging multiple slider, a kind of situation is to specify same pole position correction value for whole sliders, another kind of situation is slider is divided into multiple groups, to specify different pole position correction values for difference group, and a kind of situation is all to specify different pole position correction values for whole sliders.When specifying same pole position correction value for whole sliders, owing to slider is arranged on stator bearing of trend at each interval, therefore, for different sliders, the optimum angle position correction value of different sliders is the most different；Having the slider of Angle Position corrected value of off-target value for those, thrust will reduce.Therefore, generally slider is divided into multiple groups, specifies different Angle Position corrected values for difference group, or all specify different Angle Position corrected values for whole sliders.When specifying different Angle Position corrected values by this way, the electric machine controller 50 being required to be Fig. 3 is separately provided each Angle Position corrected value.When electric machine controller is built in such as motor driver (not shown), arrange corresponding to slider quantity or the driving means of slider group quantity.In this case, the position detector 12 of Fig. 3 generally can be used together with other slider.Based on foregoing, when i.e. box lunch arranges multiple slider, it is possible to obtain the benefit being similar to the present invention.

Claims (10)

1., for the method that controls linear electric motors, described linear electric motors have stator that the mode that extends arranges and move along this stator Dynamic slider, said method comprising the steps of:

Detect the stroke position of the described slider moved along the bearing of trend of stator；

Based on for correcting described stator salient poles offsets and multiple corresponding to along stator bearing of trend along the position of stator bearing of trend Each stroke position in stroke position and the pole position correction value that prestores, derive at detected slider stroke position The pole position correction value at place；

Based on position correction value in pole obtained by detected slider stroke position and derivation, calculate the position, pole of described slider, should Position, pole is the relative position between described slider magnetic pole and described stator salient poles；

Based on position, calculated slider pole, in the coil being arranged on described stator or described slider, input electric energy, to drive Dynamic described linear electric motors,

It is characterized in that:

Stator is formed by arranging the multiple stator segment along described stator bearing of trend, and

At least one pole position correction value is prestored for each described stator segment.

Method for controlling linear electric motors the most according to claim 1, it is characterised in that:

The plurality of stator segment is component separated from one another.

Method for controlling linear electric motors the most according to claim 1, it is characterised in that:

Each stator segment in the plurality of stator segment be by one piece along described stator bearing of trend, relative to punching press use Single punching press that stamping machine order is carried out time mobile and formed；And described stamping machine has carried out Multi-step forming, thus is formed many Individual stator segment.

4. according to the method being used for controlling linear electric motors according to any one of Claim 1-3, it is characterised in that:

For pole position correction value, the value at multiple stroke positions in a certain distance apart from one another is stored；And

Deriving the pole position correction value of section between the multiple stroke positions storing value, described pole position correction value was equal to should The pole position correction value of section end.

5. according to the method being used for controlling linear electric motors according to any one of Claim 1-3, it is characterised in that:

For pole position correction value, the value at multiple stroke positions in a certain distance apart from one another is stored；And

Derive the pole position correction value of section between the multiple stroke positions storing value, described pole position correction Zhi Weigai district The meansigma methods of the pole position correction value at section two ends.

6. according to the method being used for controlling linear electric motors according to any one of Claim 1-3, it is characterised in that:

For described pole position correction value, the value at multiple stroke positions in a certain distance apart from one another is stored；And

Deriving the pole position correction value of section between the multiple stroke positions storing value, described pole position correction value is at this Section two linear insertion pole position correction value and the value that obtains.

7., for the method calculating the position, pole of the slider of linear electric motors, described linear electric motors have to extend what mode was arranged Stator and the slider moved along this stator, said method comprising the steps of:

Obtaining along the pole position correction value at multiple stroke positions of described stator bearing of trend, described pole position correction value is used for correcting institute State the stator salient poles position skew along stator bearing of trend, and storage is corresponding with the described stroke position along stator bearing of trend Pole position correction value；

The stroke position of the described slider that detection is moved along described stator bearing of trend；

The pole position correction value of the reading slider stroke position corresponding to being detected, and calculate at detected slider stroke position The pole position correction value at place；And

Based on detected described slider stroke position and calculated pole position correction value, calculate the position, pole of described slider, It is characterized in that:

Described stator is formed by arranging the multiple stator segment along described stator bearing of trend, and

At least one pole position correction value is prestored for each described stator segment.

Method the most according to claim 7, it is characterised in that:

The plurality of stator segment is component separated from one another.

Method the most according to claim 7, it is characterised in that:

Each stator segment in the plurality of stator segment be by one piece along described stator bearing of trend, relative to punching press use Single punching press that stamping machine order is carried out time mobile and formed；And described stamping machine has carried out Multi-step forming, thus is formed many Individual stator segment.

Method the most according to claim 7, it is characterised in that:

Described stator is to constitute by arranging the described stator segment of stamped formation continuously along the longitudinal direction of stator；And For each described stator segment, obtain and store at least one pole position correction value.