CN112234892A - Method for suppressing thrust fluctuation of linear motor, related equipment and medium - Google Patents
Method for suppressing thrust fluctuation of linear motor, related equipment and medium Download PDFInfo
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
- H02P21/05—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation specially adapted for damping motor oscillations, e.g. for reducing hunting
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
- H02P21/14—Estimation or adaptation of machine parameters, e.g. flux, current or voltage
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
- H02P21/14—Estimation or adaptation of machine parameters, e.g. flux, current or voltage
- H02P21/18—Estimation of position or speed
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
- H02P21/22—Current control, e.g. using a current control loop
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P25/00—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details
- H02P25/02—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details characterised by the kind of motor
- H02P25/06—Linear motors
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Abstract
The invention provides a method for suppressing thrust fluctuation of a linear motor, related equipment and a medium, wherein the method comprises the following steps: acquiring a mapping relation I between current and position data corresponding to force fluctuation of a linear motor under the condition of no operating current0X(ii) a Obtaining a mapping relation I 'between a current value and position data corresponding to the linear motor under the condition of switching on a test current'aXSaid test current value is non-zero; according to the mapping relation I0XA current value I of the test currentaAnd the mapping relationship I'aXObtained byMapping relation I of current value and position data corresponding to thrust fluctuation caused by test currentaX(ii) a According to the mapping relation IaXObtaining a mapping relation I between a current value corresponding to thrust fluctuation caused by a preset operation current and position databX(ii) a Mapping the relation I0XAnd the mapping relation IbXA control system stored in the linear motor for applying a compensation current to suppress thrust fluctuation when the linear motor is operated, according to the mapping relation I0XAnd a mapping relation IbXTo calculate the current value of the compensation current.
Description
[ technical field ] A method for producing a semiconductor device
The invention relates to the technical field of linear motors, in particular to a method for inhibiting thrust fluctuation of a linear motor, related equipment and a medium.
[ background of the invention ]
A linear motor is a transmission device that directly converts electric energy into mechanical energy for linear motion without any intermediate conversion mechanism. The rotary motor can be seen as being formed by cutting a rotary motor in the radial direction and expanding the rotary motor into a plane.
The thrust fluctuation of the linear motor is one of the main defects in the application aspect, because the thrust fluctuation is the cause of the vibration and noise of the motor, and particularly, the thrust fluctuation can cause resonance when the linear motor runs at low speed, thereby influencing the use effect.
In the design of linear motors, reducing the thrust fluctuation is one of its main objectives, and the common methods are: the motor is controlled to move to a corresponding position, and a compensation value of the operating current is calculated according to the acquired data set by acquiring current and position information in the process, but the method can only compensate thrust fluctuation of the linear motor caused by positioning force, and thrust fluctuation caused by other various factors exists in the motor structure and is not effectively inhibited.
[ summary of the invention ]
In view of the above, it is necessary to provide a method, related apparatus and medium for suppressing thrust fluctuation of a linear motor, which are used to solve the problem that thrust fluctuation generated in the linear motor cannot be effectively suppressed and the working effect of the linear motor is affected.
The technical scheme of the invention is as follows:
in one aspect, a method for suppressing thrust fluctuation of a linear motor is provided, including:
step S0, acquiring the mapping relation N of the thrust and the current of the linear motorI;
Step S1, obtaining the mapping relation I between the current and the position data corresponding to the thrust fluctuation of the linear motor under the condition of no operation current0X;
Step S2, obtaining the mapping relation F of the thrust and position data corresponding to the linear motor under the condition of switching on the test currentaXAccording to the mapping relation FaXAnd the mapping relation NIAcquiring a mapping relation I 'between a current value and position data corresponding to the linear motor under the condition of switching on the test current'aXSaid test current value is non-zero;
step S3, according to the mapping relation I0XA current value I of the test currentaAnd the mapping relationship I'aXObtaining a mapping relation I between a current value corresponding to thrust fluctuation caused by the test current and position dataaX;
Step S4, according to the mapping relation IaXObtaining a mapping relation I between a current value corresponding to thrust fluctuation caused by a preset operation current and position databX;
Step S5, the mapping relation I is processed0XAnd the mapping relation IbXA control system stored in the linear motor, applying a compensation current to the linear motor to suppress thrust fluctuation of the linear motor when the linear motor is in operation, and according to the mapping relation I0XAnd the mapping relation IbXTo calculate a current value of the compensation current.
Optionally, the step S1 includes:
controlling the operating current of the linear motor to be zero, controlling the rotor of the linear motor to move at a constant speed through external force, acquiring the thrust force applied to the linear motor corresponding to the rotor at different positions in the moving process, and obtaining the thrust force applied to the linear motor under the condition of no operating currentMapping relation F of thrust and position data of linear motor0X;
According to the mapping relation NIAnd said mapping relation F0XObtaining the mapping relation I0X。
Optionally, the step S2 includes:
controlling the operation current of the linear motor to be a test current, controlling the rotor of the linear motor to move at a constant speed through an external force, acquiring the thrust force applied to the linear motor corresponding to the rotor at different positions in the moving process, and obtaining a mapping relation F between the thrust force of the linear motor and position data under the test currentaX;
According to the mapping relation NIAnd said mapping relation FaXObtaining the mapping relation I'aX。
Optionally, the step S3 includes:
obtaining the mapping relation I according to the following relation equationaX:
At each position, the current value corresponding to the thrust fluctuation caused by the test current is equal to the mapping relation I'aXSubtracting the current value I of the test current from the calculated current valueaAnd then subtracting from said mapping relation I0XThe resulting current value is calculated.
Optionally, the step S5 includes:
obtaining a preset current value I of the operation currentb;
According to the mapping relation I0XAnd the mapping relation IbXDetermining a mapping relation I between the current value of the compensation current and the position datab0X(ii) a According to the mapping relation Ib0XObtaining the current value of the compensation current at each position;
controlling the operation current of the linear motor to be adjusted to a target current value at each position, wherein the target current value is the current value of the compensation current and the current value I of the preset operation currentbAnd (4) summing.
Optionally, the step S5 further includes:
obtaining the mapping relation I according to the following relation equationb0X:
At each position, the current value of the compensation current is equal to the mapping relation I0XThe calculated current value is added by the mapping relation IbXThe resulting current value is calculated.
In another aspect. There is provided a linear motor comprising a linear motor component and a control system comprising reference data obtained by the method of the first aspect, the reference data comprising a current to position data mapping I corresponding to thrust fluctuations in the absence of operating current0XMapping relation I between current value and position data corresponding to thrust fluctuation caused by preset operation currentbXThe control system is used for applying a compensation current to the linear motor to inhibit the thrust fluctuation of the linear motor when the linear motor runs and according to the mapping relation I0XAnd the mapping relation IbXTo calculate a current value of the compensation current.
In another aspect, there is provided a linear motor thrust fluctuation suppression apparatus, including:
an obtaining module, configured to obtain a mapping relation N between thrust and current of the linear motorI(ii) a Acquiring a mapping relation I between current and position data corresponding to force fluctuation of a linear motor under the condition of no operating current0X;
The acquisition module is further used for acquiring a mapping relation F between thrust and position corresponding to the linear motor under the condition of switching on the test currentaXSaid test current value is non-zero;
a processing module to:
according to the mapping relation NIAnd a mapping relationship FaXObtaining a mapping relation I 'between a current value and position data corresponding to the linear motor under the condition of switching on a test current'aX
According to the mapping relation I0XThe mapping relation NIAnd the mapping relationship I'aXObtained byObtaining a mapping relation I between a current value corresponding to thrust fluctuation caused by the test current value and position dataaX;
According to the mapping relation IaXObtaining a mapping relation I between a current value corresponding to thrust fluctuation caused by a preset operation current and position databX;
Mapping the relation I0XAnd the mapping relation IbXAnd the current value is stored in a control system of the linear motor and is used for calculating the current value of the compensation current applied when the linear motor runs so as to realize the suppression of the thrust fluctuation of the linear motor.
In another aspect, there is provided a storage medium storing a computer program of instructions which, when executed by a processor, causes the processor to perform the steps of the first aspect and any one of its possible implementations as described above.
In another aspect, there is provided a computer device comprising at least one memory storing a computer program of instructions, at least one processor, the computer program of instructions, when executed by the processor, causing the processor to perform the steps of the first aspect and any possible implementation thereof as described above.
The invention has the beneficial effects that: the mapping relation between the thrust and position data output by the linear motor when the linear motor moves at a constant speed is measured at 0 operating current and at the test current, then the mapping relation between two groups of current and position data at an expected stroke is calculated according to the thrust and current relation of the motor, the mapping relation is converted into the mapping relation between the current and position data under a certain specific current, the mapping relation is interpolated and compensated to obtain the mapping relation between the current and position data corresponding to the thrust fluctuation caused by the preset operating current, the mapping relation between the current and position data corresponding to the 0 operating current and the mapping relation between the current and position data corresponding to the thrust fluctuation caused by the preset operating current are stored in a control system of the linear motor, the mapping relation can be used for compensating any operating current when the linear motor works, and simultaneously the thrust fluctuation of the linear motor caused by the positioning force and the thrust fluctuation caused by the current amplitude change are inhibited, the fluctuation of the output thrust of the linear motor is comprehensively and effectively inhibited finally.
[ description of the drawings ]
Fig. 1 is a schematic flow chart of a method for suppressing thrust fluctuation of a linear motor according to the present invention;
fig. 2 is a schematic flow chart of another method for suppressing thrust fluctuation of a linear motor according to the present invention;
fig. 3 is a schematic structural diagram of a device for suppressing thrust fluctuation of a linear motor provided by the present invention;
fig. 4 is a schematic structural diagram of an electronic device provided in the present invention.
[ detailed description ] embodiments
In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The terms "first," "second," and the like in the description and claims of the present invention and in the above-described drawings are used for distinguishing between different objects and not for describing a particular order. Furthermore, the terms "include" and "have," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or inherent to such process, method, article, or apparatus.
Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the invention. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.
The linear motor mentioned in the embodiments of the present invention is a transmission device that directly converts electric energy into mechanical energy for linear motion without any intermediate conversion mechanism. The rotary motor can be seen as being formed by cutting a rotary motor in the radial direction and expanding the rotary motor into a plane. Linear motors are also known as linear motors, pusher motors, etc.
Generally, the side evolved from the stator is called primary, and the side evolved from the mover (rotor) is called secondary. In practice, the primary and secondary are manufactured in different lengths to ensure that the coupling between the primary and secondary remains constant over the required range of travel. The linear motor can be a short primary long secondary and can also be a long primary short secondary. In consideration of manufacturing cost and operating cost, a linear induction motor is taken as an example: when the primary winding is connected with an AC power supply, a travelling wave magnetic field is generated in the air gap, and the secondary winding is cut by the travelling wave magnetic field to induce electromotive force and generate current, and the current and the magnetic field in the air gap interact to generate electromagnetic thrust.
Terms such as position data, position information, or position movement of the linear motor in the embodiments of the present application may be understood as referring to the mover of the linear motor, that is, the movement, position, and the like of the mover.
The embodiments of the present invention will be described below with reference to the drawings.
Referring to fig. 1, fig. 1 is a schematic flow chart illustrating a method for suppressing thrust fluctuation of a linear motor according to an embodiment of the present invention. The method can comprise the following steps:
101. obtaining a mapping relation N of thrust and current of the linear motorI(ii) a Acquiring a mapping relation I between current and position data corresponding to force fluctuation of a linear motor under the condition of no operating current0X。
The implementation subject of the embodiment of the present invention may be a device for suppressing thrust fluctuation of a linear motor, where the device for suppressing thrust fluctuation of a linear motor may suppress thrust fluctuation generated by the linear motor, or may establish a model for suppressing thrust fluctuation for the linear motor. In an alternative embodiment, the suppression device for thrust fluctuation of the linear motor may be a system including the linear motor, or may be an electronic device, and the electronic device may be a terminal device including, but not limited to, other portable devices such as a laptop computer, a tablet computer, or a desktop computer.
In permanent magnet machines, there is an electromagnetic torque, called cogging torque, or cogging torque, even if the stator windings are not excited. The operating current in the embodiment of the present application refers to a current for controlling the linear motor, but due to the influence of the positioning force of the linear motor and the operating current during the operation of the linear motor, the actual current may not be consistent with the operating current, so that it can be understood that the current corresponding to the current is referred to in the embodiment of the present application, that is, the actual current corresponding to the operating current. That is, the mapping relationship between the current and the position data caused by the thrust fluctuation in the case of no operating current may be regarded as the mapping relationship between the current and the position data corresponding to the positioning force, may be expressed as a positioning force curve of the linear motor, and may be obtained according to actual test statistics or simulation tests.
In an optional implementation manner, the step 101 may specifically include:
controlling the operation current of the linear motor to be zero, controlling the rotor of the linear motor to move at a constant speed through an external force, acquiring the thrust force received by the linear motor corresponding to the rotor at different positions in the moving process, and obtaining the mapping relation F of the thrust force and the position data of the linear motor under the condition of no operation current0X;
According to the mapping relation NIAnd the above-mentioned mapping relation F0XObtaining the above mapping relation I0X。
Specifically, the operating current of the linear motor can be set to 0, and the linear motor is pulled by the dragging device to be uniform and slowThe corresponding position stroke is moved, the thrust of the linear motor is obtained through the measurement of the force sensor in the process, and the mapping relation between the thrust of the linear motor and the position data under the condition that the position corresponding to the thrust is 0, namely the operating current is 0, can be expressed as the thrust F under a specific position (X)0X。
In the embodiment of the present application, the relationship between the thrust and the current of the linear motor is a type of characteristic parameter of the linear motor, and may be obtained by simulation according to a test, or may be information stored in the linear motor, which is not limited herein. F can be converted by the relationship between the thrust and the current of the linear motor0XThe corresponding current-position data set can obtain the mapping relation between the corresponding current and position data when the operation current is 0, and can be represented as the current value I (corresponding to the positioning force) corresponding to the operation current of 0 at the specific position (X)0X。
102. Obtaining a mapping relation I 'between a current value and position data corresponding to the linear motor under the condition of switching on a test current'aXThe test current value is non-zero.
In an optional embodiment, the obtaining of the mapping relationship I 'between the current and the position data corresponding to the linear motor under the condition of the test current is performed'aXThe method comprises the following steps:
controlling the operation current of the linear motor to be a test current, controlling the rotor of the linear motor to move at a constant speed through an external force, collecting the thrust force received by the linear motor corresponding to the rotor at different positions in the moving process, and obtaining a mapping relation F between the thrust force of the linear motor and position data under the test currentaX;
According to the mapping relation NIAnd the above-mentioned mapping relation FaXObtaining the mapping relation I'aX。
The test current can be set according to requirements and is not 0, for example, the test current is IaUsing a specific belt force FaThe load of (2) was tested. Specifically, the operating current of the linear motor may be set to IaAnd pulled by a pair of dragging devicesMoving the linear motor at a constant speed and slowly to move corresponding position and stroke, and measuring the thrust of the linear motor and the position corresponding to the thrust by a force sensor in the process, namely, the operating current is IaIn the case of (2), the mapping relationship between the thrust of the linear motor and the position data can be expressed as a thrust F at a specific position (X)aX。
Further, F can be obtained by conversion from the relationship between the thrust and the current of the linear motoraXA corresponding current-position data set, i.e. a data set obtained at an operating current of IaThe mapping relationship between the corresponding current and the position data in the case of (2) can be expressed as that the operating current is I at the specific position (X)aCorresponding current value IaX。
103. According to the above-mentioned mapping relation I0XA current value I of the test currentaAnd the above mapping relationship I'aXObtaining a mapping relation I between a current value corresponding to the thrust fluctuation caused by the test current and the position dataaX。
In the embodiment of the present application, according to the measured mapping relationship and the relationship between the thrust and the current of the linear motor, a current value corresponding to the thrust fluctuation caused by a specific current can be derived, and then the thrust fluctuation suppression of the linear motor is performed at any current.
In the embodiment of the application, a test is performed in an experimental stage under the condition of no operating current, and in this case, the mapping relationship between the current and the position data corresponding to the thrust fluctuation under the condition of no operating current can be understood as the mapping relationship between the current and the position data corresponding to the thrust fluctuation caused only by the positioning force in the linear motor. Therefore, it is possible to derive thrust fluctuations due to only the operating current from the obtained mapping relationship.
The operating current in the embodiment of the present application refers to a current for controlling the linear motor, but due to the influence of the positioning force of the linear motor and the operating current during the operation of the linear motor, the actual current may not be consistent with the operating current, so that it can be understood that the current corresponding to the current is referred to in the embodiment of the present application, that is, the actual current corresponding to the operating current.
In one embodiment, the step 103 specifically includes:
the above-mentioned mapping relation I is obtained according to the following relation equationaX:
At each position, the current value corresponding to the thrust fluctuation caused by the test current is equal to the mapping relation I'aXSubtracting the current value I of the test current from the calculated current valueaThen subtract the above mapping relation I0XThe resulting current value is calculated.
In the embodiment of the present application, the influence of thrust fluctuation caused by the positioning force needs to be removed to obtain the mapping relationship between the current and the position data corresponding to the thrust fluctuation caused only by the specific test current. Specifically, the current value I is measuredaThe current value corresponding to the thrust fluctuation is IaX=I′aX-Ia-I0X。
104. According to the above-mentioned mapping relation IaXObtaining a mapping relation I between a current value corresponding to thrust fluctuation caused by a preset operation current and position databX。
In the embodiment of the application, according to the mapping relation between the current and the position data corresponding to the thrust fluctuation caused by the test current value, any operation current I can be obtained through derivation and calculationbThe current-position data corresponding to the resulting thrust fluctuation is IbXThe mapping relation between the current and the position data corresponding to the thrust fluctuation caused by the preset operation current can be used for a linear motor control system. The current-position data corresponding to a plurality of groups of thrust fluctuation caused by different current values can be obtained according to the existing corresponding relation, and then the current-position data are integrated to obtain the thrust fluctuation. In particular, an arbitrary operating current IbThe mapping relation of the current corresponding to the caused thrust fluctuation and the position data is IbX=Ib/Ia·IaX。
Mapping relation I of current and position data corresponding to thrust fluctuation caused by the preset operation currentbXThe linear motor can be knownWhen the current is operated, the mapping relation between the current and the position data corresponding to the thrust fluctuation caused by the operation current is determined.
105. Mapping the above relation I0XAnd the above-mentioned mapping relation IbXA control system stored in the linear motor for applying a compensation current to the linear motor to suppress a thrust fluctuation of the linear motor when the linear motor is operated, based on the mapping relation I0XAnd the above-mentioned mapping relation IbXTo calculate the current value of the compensation current.
After obtaining the mapping relationship between the current and the position data caused by the thrust fluctuation in the case of no operating current and the mapping relationship between the current and the position data corresponding to the thrust fluctuation caused by the preset operating current value, the mapping relationship between the compensation current and the position data corresponding to the preset operating current, namely the current compensation including the thrust fluctuation caused by the positioning force and the operating current, can be integrated and stored in the control system of the linear motor.
In one embodiment, the mapping relationship I can be based on0XAnd the above-mentioned mapping relation IbXAdding the current corresponding to the thrust fluctuation caused by the current value corresponding to each position data and the current corresponding to the positioning force to obtain each compensation current value corresponding to each position data;
the mapping relation between each compensation current value and each position data is used as the mapping relation Ib0X。
In particular, I can beb0X=IbX+I0XAnd interpolating to enter the linear motor control system as a corresponding current and position mapping data set (namely the mapping relation between the compensation current and the position data corresponding to the preset operation current) for calculating a compensation value of the operation current so as to inhibit thrust fluctuation caused by positioning force and the operation current in the linear motor.
The invention respectively tests the mapping relation of current and position data when the linear motor moves expected travel under the conditions of no load and loaded force when the linear motor is horizontally installed, converts the mapping relation into the mapping relation of current and position data under a specific current, interpolates and compensates the mapping relation to obtain the mapping relation of current and position data corresponding to thrust fluctuation caused by preset operation current, stores the mapping relation of current and position data caused by thrust fluctuation (positioning force) under the condition of no operation current and the mapping relation of current and position data corresponding to the thrust fluctuation caused by the preset operation current in a control system of the linear motor, can calculate the compensation value of the operation current in direct proportion to the thrust fluctuation of the linear motor, can compensate any operation current by using the mapping relation when the linear motor works, and simultaneously restrains the thrust fluctuation caused by the positioning force and the thrust fluctuation caused by the operation current, the fluctuation of the output thrust of the linear motor is comprehensively and effectively inhibited finally.
To more clearly illustrate the technical solution in the embodiment of the present invention, refer to fig. 2, and fig. 2 is a schematic flowchart of another method for suppressing thrust fluctuation of a linear motor according to the embodiment of the present invention. As shown in fig. 2, the method may be performed after the steps in the embodiment shown in fig. 1, and is used as an application of the embodiment shown in fig. 1 to obtain data. The method comprises the following steps:
201. obtaining a preset current value I of the operation currentb。
202. According to the above-mentioned mapping relation I0XAnd the above-mentioned mapping relation IbXDetermining the mapping relation I between the current value of the compensation current and the position datab0X(ii) a According to the above-mentioned mapping relation Ib0XAnd obtaining the current value of the compensation current at each position.
203. Controlling the operation current of the linear motor to be adjusted to a target current value at each position, wherein the target current value is the current value of the current and the current value I of the preset operation currentbAnd (4) summing.
The implementation subject of the embodiment of the present invention may be a device for suppressing thrust fluctuation of a linear motor, which may suppress thrust fluctuation generated by the linear motor, and specifically, the linear motor may perform the steps in the embodiment of the present invention. It is also possible to be a linear motor including a linear motor part and a control system including a preset mapping relationship of compensation current and position data obtained by the method in the embodiment shown in fig. 1, the control system may calculate a compensation value of operation current proportional to thrust fluctuation of the linear motor based on the mapping relationship of current and position data caused by the thrust fluctuation in the absence of the operation current and the mapping relationship of current and position data corresponding to the thrust fluctuation caused by the preset operation current, and compensate the operation current using the compensation value.
In an alternative embodiment, the device for suppressing thrust fluctuation of the linear motor may be a system including the linear motor, or may be an electronic device, and the electronic device may be a terminal device including, but not limited to, other portable devices such as a laptop computer, a tablet computer, or a desktop computer, in which case the steps in the embodiment of the present invention are executed in a software simulation manner.
On the basis of the steps of the embodiment shown in fig. 1, a compensation current value corresponding to thrust fluctuation generated by the linear motor under the influence of any operation current can be obtained, and the thrust fluctuation is suppressed in a pre-compensation mode.
Wherein the mapping relation of the current and the position data caused by the thrust fluctuation under the condition of no operation current is represented as I0XA predetermined current value IbThe mapping relation of the current corresponding to the caused thrust fluctuation and the position data is represented as IbX。
Can be combined with Ib0X=IbX+I0XCalculating a compensation value for the operating current as a complete compensation current calculation rule, in particular for any operating current value I when the linear motor is runningbThe compensated current value I can be calculated according to the mapping relation between the preset compensation current and the position datab0XCompensating for a particular current I at a particular location Xb0XAnd finally the current I of the actual operation of the motorb_total=Ib+Ib0X。
When thrust fluctuation suppression caused by positioning force is considered, the motor can be controlled to move to a corresponding position, the current and position information in the period is collected, and the obtained data set is used as a compensation value of the operation current by an interpolation method. But only compensates for thrust fluctuations of the linear motor due to positioning forces. In the linear motor, the amplitude variation of the operating current is also an important reason for influencing the thrust fluctuation of the linear motor, and if the factor is not compensated and corrected, the thrust output effect of the linear motor is finally influenced, so that the thrust fluctuation is still not effectively inhibited.
In the embodiment of the invention, the influence of the operating current on the thrust fluctuation of the linear motor is considered, the thrust-position data output by the linear motor during uniform motion when the operating current is 0 and a certain value (test current) are respectively measured, then two groups of actual current-position data during expected travel are calculated according to the relationship between the thrust and the current of the motor, and the corresponding current-position data set is interpolated and compensated into the operating current according to the operating current value, so that the fluctuation of the thrust output by the linear motor is finally inhibited. The linear motor can compensate any operation current by utilizing the mapping relation when working, and simultaneously restrains thrust fluctuation caused by positioning force and thrust fluctuation caused by operation current, so that finally the fluctuation of the output thrust of the linear motor is more comprehensively and effectively restrained.
Based on the description of the embodiment of the method for suppressing thrust fluctuation of the linear motor, the embodiment of the invention also discloses a device for suppressing thrust fluctuation of the linear motor. Referring to fig. 3, the linear motor thrust fluctuation suppressing apparatus 300 includes:
an obtaining module 310, configured to obtain a mapping relationship N between thrust and current of the linear motorI(ii) a Acquiring a mapping relation I between current and position data corresponding to force fluctuation of a linear motor under the condition of no operating current0X;
The obtaining module 310 is further configured to obtain a mapping relationship F between a thrust and a position corresponding to the linear motor when the test current is switched onaXThe test current value is nonzero;
a processing module 320 configured to:
according to the mapping relation NIAnd a mapping relationship FaXObtaining a mapping relation I 'between a current value and position data corresponding to the linear motor under the condition of switching on a test current'aX;
According to the above-mentioned mapping relation IaXObtaining a mapping relation I between a current value corresponding to thrust fluctuation caused by a preset operation current and position databX;
Mapping the above relation I0XAnd the above-mentioned mapping relation IbXAnd a control system stored in the linear motor for calculating a current value of a compensation current applied when the linear motor is operated to suppress a thrust ripple of the linear motor.
Optionally, the device 300 for suppressing thrust fluctuation of the linear motor further includes a compensation module 330 and a control module 340; wherein:
the obtaining module 310 is further configured to obtain a current value I of the preset operating currentb;
The compensation module 330 is configured to obtain the mapping relationship I0XAnd the above-mentioned mapping relation IbXDetermining the mapping relation I between the current value of the compensation current and the position datab0X(ii) a According to the above-mentioned mapping relation Ib0XObtaining the current value of the compensation current at each position;
the control module 340 is configured to control the operating current of the linear motor to be adjusted to a target current value at each position, where the target current value is a current value of the compensation current and a current value I of the preset operating currentbAnd (4) summing.
According to an embodiment of the present invention, each step involved in the method shown in fig. 1 and fig. 2 may be performed by each module in the linear motor thrust fluctuation suppression apparatus 300 shown in fig. 3, and is not described herein again.
In the linear motor thrust fluctuation suppression device 300 according to the embodiment of the present invention, the linear motor thrust fluctuation suppression device 300 may obtain a mapping relationship between current and position data caused by thrust fluctuation of the linear motor in the absence of an operation current, and a mapping relationship between current and position data corresponding to the linear motor in the presence of a test current, the test current being non-zero, and may obtain a mapping relationship between current and position data corresponding to thrust fluctuation caused by a test current value according to the mapping relationship between the thrust and current of the linear motor, and obtain a mapping relationship between current and position data corresponding to thrust fluctuation caused by a preset operation current according to a mapping relationship between current and position data corresponding to thrust fluctuation caused by a test current value, and then obtain a mapping relationship between current and position data caused by thrust fluctuation in the absence of an operation current and correspond to thrust fluctuation caused by a preset operation current The mapping relation between the current and the position data is stored in a control system of the linear motor so as to be used for calculating a compensation value of the operation current in direct proportion to the thrust fluctuation of the linear motor, when the linear motor works, the mapping relation can be used for compensating any operation current, and simultaneously the thrust fluctuation caused by the positioning force and the thrust fluctuation caused by the operation current are restrained, so that the fluctuation of the output thrust of the linear motor is more comprehensively and effectively restrained finally.
Based on the description of the method embodiment and the device embodiment, the embodiment of the invention also provides the linear motor. The linear motor comprises at least linear motor components and a control system comprising reference data obtained by the method of the embodiment shown in fig. 1, the reference data comprising a mapping I of current to position data corresponding to thrust fluctuations in the absence of operating current0XMapping relation I between current value and position data corresponding to thrust fluctuation caused by preset operation currentbXThe control system is used for applying a compensation current to the linear motor to inhibit the thrust fluctuation of the linear motor when the linear motor runs according to the mapping relation I0XAnd the above-mentioned mapping relation IbXTo calculate the current value of the compensation current.
Based on the description of the method embodiment and the device embodiment, the embodiment of the invention also provides electronic equipment. Referring to fig. 4, the electronic device at least includes a processor 410, a nonvolatile storage medium 420, an internal memory 430, and a network interface 440, wherein the processor 410, the nonvolatile storage medium 420, the internal memory 430, and the network interface 440 may be connected by a system bus 450 or other means, and may communicate with other devices through the network interface 440.
A non-volatile storage medium 420, i.e., a computer storage medium, may be stored in the memory for storing computer programs and an operating system, and the internal memory 430 may also store computer programs comprising program instructions that are executable by the processor. The processor 410 (or CPU) is a computing core and a control core of the terminal, and is adapted to implement one or more instructions, and in particular, is adapted to load and execute the one or more instructions so as to implement a corresponding method flow or a corresponding function; in one embodiment, the processor 410 described above in the embodiments of the present invention may be used to perform a series of processes, including the methods in the embodiments shown in fig. 1 and fig. 2, and so on.
The embodiment of the invention also provides a computer storage medium (Memory), which is a Memory device in the terminal and is used for storing programs and data. It is understood that the computer storage medium herein may include a built-in storage medium in the terminal, and may also include an extended storage medium supported by the terminal. The computer storage medium provides a storage space that stores an operating system of the terminal. Also stored in the memory space are one or more instructions, which may be one or more computer programs (including program code), suitable for loading and execution by the processor. The computer storage medium may be a high-speed RAM memory, or may be a non-volatile memory (non-volatile memory), such as at least one disk memory; and optionally at least one computer storage medium located remotely from the processor.
In one embodiment, one or more instructions stored in a computer storage medium may be loaded and executed by a processor to perform the corresponding steps in the above embodiments; in particular implementations, one or more instructions in the computer storage medium may be loaded by the processor and executed to perform any step of the method in fig. 1 and/or fig. 2, which is not described herein again.
It can be clearly understood by those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described apparatuses and modules may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.
In the embodiments provided in the present invention, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the division of the module is only one logical division, and other divisions may be possible in actual implementation, for example, a plurality of modules or components may be combined or integrated into another system, or some features may be omitted, or not performed. The shown or discussed mutual coupling, direct coupling or communication connection may be an indirect coupling or communication connection of devices or modules through some interfaces, and may be in an electrical, mechanical or other form.
Modules described as separate parts may or may not be physically separate, and parts displayed as modules may or may not be physical modules, may be located in one place, or may be distributed on a plurality of network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment.
In the above embodiments, the implementation may be wholly or partially realized by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. The procedures or functions according to the embodiments of the invention are brought about in whole or in part when the computer program instructions are loaded and executed on a computer. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored on or transmitted over a computer-readable storage medium. The computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by wire (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)), or wirelessly (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, a data center, etc., that includes one or more of the available media. The usable medium may be a read-only memory (ROM), or a Random Access Memory (RAM), or a magnetic medium, such as a floppy disk, a hard disk, a magnetic tape, a magnetic disk, or an optical medium, such as a Digital Versatile Disk (DVD), or a semiconductor medium, such as a Solid State Disk (SSD).
Claims (10)
1. A method for suppressing thrust fluctuation of a linear motor is characterized by comprising the following steps:
step S0, acquiring the mapping relation N of the thrust and the current of the linear motorI;
Step S1, obtaining the mapping relation I between the current and the position data corresponding to the thrust fluctuation of the linear motor under the condition of no operation current0X;
Step S2, obtaining the mapping relation F of the thrust and position data corresponding to the linear motor under the condition of switching on the test currentaXAccording to the mapping relation FaXAnd the mapping relation NIAcquiring a mapping relation I 'between a current value and position data corresponding to the linear motor under the condition of switching on the test current'aXSaid test current value is non-zero;
step S3, according to the mapping relation I0XA current value I of the test currentaAnd the mapping relationship I'aXObtaining a mapping relation I between a current value corresponding to thrust fluctuation caused by the test current and position dataaX;
Step S4, according to the mapping relation IaXObtaining a mapping relation I between a current value corresponding to thrust fluctuation caused by a preset operation current and position databX;
Step S5, the mapping relation I is processed0XAnd the mapping relation IbXA control system stored in the linear motor, applying a compensation current to the linear motor to suppress thrust fluctuation of the linear motor when the linear motor is in operation, and according to the mapping relation I0XAnd the mapping relation IbXTo calculate a current value of the compensation current.
2. The method for suppressing thrust fluctuation of a linear motor according to claim 1, wherein the step S1 includes:
controlling the operating current of the linear motor to be zero, controlling a rotor of the linear motor to move at a constant speed through external force, acquiring thrust force applied to the linear motor corresponding to the rotor at different positions in the moving process, and obtaining a mapping relation F between the thrust force of the linear motor and position data under the condition of no operating current0X;
According to the mapping relation NIAnd said mapping relation F0XObtaining the mapping relation I0X。
3. The method for suppressing thrust fluctuation of a linear motor according to claim 2, wherein the step S2 includes:
controlling the operation current of the linear motor to be a test current, controlling the rotor of the linear motor to move at a constant speed through an external force, acquiring the thrust force applied to the linear motor corresponding to the rotor at different positions in the moving process, and obtaining a mapping relation F between the thrust force of the linear motor and position data under the test currentaX;
According to the mapping relation NIAnd said mapping relation FaXObtaining the mapping relation I'aX。
4. The linear motor thrust fluctuation suppression method according to any one of claims 1 to 3, wherein the step S3 includes:
obtaining the mapping relation I according to the following relation equationaX:
At each position, the current value corresponding to the thrust fluctuation caused by the test current is equal to the mapping relation I'aXSubtracting the current value I of the test current from the calculated current valueaAnd then subtracting from said mapping relation I0XThe resulting current value is calculated.
5. The method for suppressing thrust fluctuation of a linear motor according to claim 4, wherein the step S5 includes:
obtaining a preset current value I of the operation currentb;
According to the mapping relation I0XAnd the mapping relation IbXDetermining a mapping relation I between the current value of the compensation current and the position datab0X(ii) a According to the mapping relation Ib0XObtaining the current value of the compensation current at each position;
controlling the operation current of the linear motor to be adjusted to a target current value at each position, wherein the target current value is the current value of the compensation current and the current value I of the preset operation currentbAnd (4) summing.
6. The method for suppressing thrust fluctuation of a linear motor according to claim 5, wherein the step S5 further includes:
obtaining the mapping relation I according to the following relation equationb0X:
At each position, the current value of the compensation current is equal to the mapping relation I0XThe calculated current value is added by the mapping relation IbXThe resulting current value is calculated.
7. A linear motor is characterized by comprising a linear motor componentAnd a control system comprising reference data obtained by the method according to any one of claims 1 to 6, the reference data comprising a mapping I of current to position data corresponding to thrust fluctuations in the absence of an operating current0XMapping relation I between current value and position data corresponding to thrust fluctuation caused by preset operation currentbXThe control system is used for applying a compensation current to the linear motor to inhibit the thrust fluctuation of the linear motor when the linear motor runs and according to the mapping relation I0XAnd the mapping relation IbXTo calculate a current value of the compensation current.
8. A linear motor thrust fluctuation suppression device, comprising:
an obtaining module, configured to obtain a mapping relation N between thrust and current of the linear motorI(ii) a Acquiring a mapping relation I between current and position data corresponding to force fluctuation of a linear motor under the condition of no operating current0X;
The acquisition module is further used for acquiring a mapping relation F between thrust and position corresponding to the linear motor under the condition of switching on the test currentaXSaid test current value is non-zero;
a processing module to:
according to the mapping relation NIAnd a mapping relationship FaXObtaining a mapping relation I 'between a current value and position data corresponding to the linear motor under the condition of switching on a test current'aX;
According to the mapping relation I0XThe mapping relation NIAnd the mapping relationship I'aXObtaining a mapping relation I between a current value and position data corresponding to thrust fluctuation caused by the test current valueaX;
According to the mapping relation IaXObtaining a mapping relation I between a current value corresponding to thrust fluctuation caused by a preset operation current and position databX;
Mapping the relation I0XAnd the above-mentioned enantiomerRadial relation IbXAnd the current value is stored in a control system of the linear motor and is used for calculating the current value of the compensation current applied when the linear motor runs so as to realize the suppression of the thrust fluctuation of the linear motor.
9. A storage medium storing a computer program of instructions which, when executed by a processor, causes the processor to carry out the steps of the method according to any one of claims 1 to 6.
10. A computer device comprising at least one memory storing a program of computer instructions which, when executed by the processor, causes the processor to perform the steps of the method of any one of claims 1 to 6, at least one processor.
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