A micro motor stator coil winding machine and control method thereof

Abstract

The present application relates to the technical field of motor stator coil winding machine control, and specifically to a micro motor stator coil winding machine and a control method thereof, which specifically includes: determining the transmission hysteresis value of the indirect tension value of the enameled wire through the synchronous fluctuation between the actual tension measurement sequence and the indirect tension sequence under different moving step sizes, performing hysteresis correction on the indirect tension value, and considering the tension cycle correlation strength during the operation stage of the stator coil winding machine to evaluate the degree of interference distortion; obtaining the winding looseness of the enameled wire through the changing trend of the wire pay-off line speed and the difference between the actual tension measurement value and the set value; obtaining weights through these two indicators, performing weighted fusion on the actual measurement value and the predicted value, obtaining the tension correction value, and combining with the PID control algorithm to control the enameled wire tension of the motor stator coil winding machine; improving the accuracy of the tension control of the motor stator coil winding machine, enhancing the tension control effect of the coil winding machine, and reducing the tension fluctuation rate of the enameled wire.

Description

Technical Field

[0001] The present application relates to the technical field of winding machine control, and in particular to a micro motor stator coil winding machine and a control method thereof. Background Art

[0002] In micromotor production, enameled wire is wound around the motor stator. The stator winding wire frames come in either round or square shapes. The stator coil winding machine winds the coils on round frames, maintaining a nearly constant wire speed and making tension control easier. However, the speed of wire wound on square frames varies significantly compared to round ones. Furthermore, the reciprocating movement of the guide needle during winding alternates with the clockwise and counterclockwise swing of the main shaft, causing dramatic wire speed fluctuations and significantly increasing the difficulty of tension control.

[0003] Tension control in motor stator coil winding machines relies on highly accurate enameled wire tension measurement. Low tension measurement accuracy leads to poor control, easily causing wire breakage due to excessive tension or loosening due to insufficient tension. Wire tension measurement methods struggle to simultaneously mitigate the effects of environmental factors and mechanical transmission errors, resulting in low tension measurement accuracy and impacting the effectiveness of tension control in motor stator coil winding machines. Summary of the Invention

[0004] In order to solve the above technical problems, the purpose of this application is to provide a micro motor stator coil winding machine and a control method thereof. The technical solutions adopted are as follows:

[0005] In a first aspect, an embodiment of the present application provides a method for controlling a micro motor stator coil winding machine, the method comprising the following steps:

[0006] During the operation of the motor stator coil winding machine, the indirect tension value of the enameled wire at each moment is obtained through the swing angle of the swing arm at each moment; the pay-off linear speed at each moment is obtained through the angular velocity of the pay-off motor at each moment; and the actual measured tension value of the enameled wire at each moment is collected;

[0007] Obtain the tension measurement sequence, indirect tension sequence, and pay-off line speed sequence within a preset time period before the current moment; determine the transmission hysteresis value of the indirect tension value of the enameled wire based on the synchronous fluctuation between the tension measurement sequence and the indirect tension sequence under different movement steps;

[0008] By predicting the indirect tension sequence, the indirect tension prediction value at the future moment is obtained, and the measurement deviation of the tension actual value at the current moment is determined based on the difference between the prediction value corresponding to the transmission lag value and the tension actual value at the current moment;

[0009] The data points in the tension measurement sequence belonging to the reciprocating motion phase of the guide needle are determined based on the degree of data chaos within the neighborhood of each data point in the tension measurement sequence; the sequence consisting of the data points of the reciprocating motion phase of the guide needle that are closest to the current moment and continuous within a preset time period before the current moment is recorded as a motion data sequence; the periodic correlation strength of the tension measurement value at the current moment is constructed based on the correlation between the motion data sequence and each preset tension period sequence;

[0010] Calculating an interference distortion assessment value of the actual tension measurement value at the current moment based on the measurement deviation and the periodic correlation strength; constructing a winding looseness of the enameled wire at the current moment based on a change trend of the pay-off line speed within the time interval of the motion data sequence and a difference between the actual tension measurement value of the element in the motion data sequence and a preset tension setting value;

[0011] The weight is determined based on the winding looseness and the interference distortion evaluation value, and the actual tension measurement at the current moment and the predicted value corresponding to the transmission lag value are weightedly fused through the weight to obtain the tension correction value at the current moment, and the tension of the enameled wire of the motor stator coil winding machine is controlled.

[0012] In one embodiment, the process of obtaining the transmission hysteresis value of the indirect tension value of the enameled wire is as follows:

[0013] Calculate the product of each element in the tension measurement sequence and the corresponding element in the indirect tension sequence under any movement step, record it as the first product, calculate the sum of all the first products of the indirect tension sequence under any movement step, record it as the waveform synchronization coefficient;

[0014] The moving step length is used as the horizontal coordinate and the waveform synchronization coefficient is used as the vertical coordinate to obtain the coordinate points corresponding to the indirect tension sequence under each moving step length. In the fitting curve obtained by nonlinear fitting of all coordinate points, the moving step length corresponding to the minimum value of the horizontal coordinate among all peak points is used as the transmission hysteresis value of the indirect tension value of the enameled wire.

[0015] In one embodiment, the process of obtaining the measurement deviation of the actual tension value at the current moment is as follows:

[0016] The transmission hysteresis value is recorded as , get the future The indirect tension prediction value at the moment is used as the indirect tension lag correction value at the current moment; the measured deviation of the tension actual value at the current moment is recorded as , The expression is:

[0017] , where is the actual measured value of tension at the current moment, is the indirect tension hysteresis correction value at the current moment, It is an exponential function with the natural constant e as its base.

[0018] In one embodiment, the process of acquiring the data points belonging to the reciprocating motion phase of the guide needle in the tension measurement sequence is as follows:

[0019] The duration of the reciprocating cycle of the guide needle of the motor stator coil winding machine is recorded as For any data point in the tension measurement sequence, the time before the acquisition moment of any data point is as the neighborhood of any data point; and taking the standard deviation of the tension measured values ​​of all data points in the neighborhood of any data point as the tension instability value of any data point;

[0020] The segmentation threshold of the tension instability value of all data points in the tension measurement sequence is obtained by the threshold segmentation algorithm; the data points whose tension instability value is greater than the segmentation threshold are used as the data points of the reciprocating motion stage of the guide needle.

[0021] In one embodiment, the expression for the periodic correlation strength of the tension measured value at the current moment is:

[0022]

[0023] Where, is the periodic correlation strength of the actual tension value at the current moment; N is the number of preset tension period sequences; is the motion data sequence at the current moment; It is the first tension cycle in the nth preset tension cycle sequence. A sequence of data elements, where is a sequence The length of the sequence; To calculate the DTW distance.

[0024] In one embodiment, the interference distortion evaluation value of the actual tension measurement value at the current moment is: a ratio of a measurement deviation of the actual tension measurement value at the current moment to a periodic correlation strength.

[0025] In one embodiment, the process of obtaining the winding looseness of the enameled wire at the current moment is:

[0026] The sequence of the line speeds at all moments within the time interval of the motion data sequence at the current moment is recorded as the line feature sequence at the current moment; the line feature sequence is used as the input of the trend test algorithm, and the output is the standardized test statistic, recorded as ; Get the preset enameled wire tension setting value, recorded as ;

[0027] The winding looseness of the enameled wire at the current moment is recorded as , The expression is:

[0028]

[0029] Where, is the sequence length of the motion data sequence at the current moment, is the actual measured value of the tension at the xth data point in the motion data sequence at the current moment, It is an exponential function with the natural constant e as its base.

[0030] In one embodiment, the tension correction value at the current moment is obtained to control the tension of the enameled wire of the motor stator coil winding machine, specifically:

[0031] The normalized value of the ratio of the winding looseness to the interference distortion evaluation value at the current moment is used as the fusion weight of the tension measurement value at the current moment; the tension correction value at the current moment is calculated based on the tension measurement value at the current moment, the indirect tension hysteresis correction value and the fusion weight;

[0032] The difference between the current tension correction value and the preset tension setting value is recorded as the tension difference. When the tension of the enameled wire is adjusted by the PID controller, when the tension difference is greater than or equal to the preset difference threshold, the integral term of the PID algorithm is cancelled. When the tension difference is less than the preset difference threshold, the integral operation of the PID algorithm is introduced to control the tension of the motor stator coil winding machine.

[0033] In one embodiment, the tension correction value is expressed as:

[0034] , where is the tension correction value at the current moment, is the fusion weight of the tension measured value at the current moment, is the actual measured value of tension at the current moment, It is the indirect tension hysteresis correction value at the current moment.

[0035] In a second aspect, an embodiment of the present application further provides a micro motor stator coil winding machine, which is applied to the micro motor stator coil winding machine control method, and the control of the motor stator coil winding machine is implemented using any of the above methods.

[0036] The embodiments of the present application have at least the following beneficial effects:

[0037] The present application determines the transmission hysteresis value of the indirect tension value of the enameled wire through the synchronous fluctuation between the actual tension measurement sequence and the indirect tension sequence under different moving step sizes, performs hysteresis correction on the indirect tension value, and considers the tension cycle correlation strength during the operation stage of the motor stator coil winding machine to comprehensively evaluate the interference distortion degree of the actual tension measurement value, thereby further improving the reliability and stability of the tension control system of the motor stator coil winding machine and reducing the winding quality problems caused by measurement errors and system hysteresis; obtains the winding looseness of the enameled wire through the change trend of the wire pay-off line speed and the difference between the actual tension measurement value and the set value, and combines the interference distortion to obtain the winding looseness of the enameled wire. The degree of authenticity is determined, and a fusion weight is constructed to comprehensively analyze the importance of the actual tension measurement value; the actual tension measurement value and the indirect tension prediction value are weightedly fused to obtain the tension correction value, eliminate the transmission lag of the indirect measurement method, improve the anti-interference ability of the direct measurement method, improve the accuracy of the enameled wire tension measurement value, and avoid the problem of excessive tension causing the enameled wire to break or too little tension causing the coil to loosen in tension control; in the process of controlling the enameled wire tension of the motor stator coil winding machine through the tension correction value, the present application provides an integral separation PID control method, which dynamically adjusts the control strategy according to the size of the tension difference between the tension correction value and the set value. When the tension difference is large, the integral term is canceled to reduce the overshoot and oscillation of the enameled wire tension control of the motor stator coil winding machine. When the difference is small, the integral term is introduced to eliminate the residual error of the enameled wire tension control, thereby improving the accuracy of the motor stator coil winding machine tension control, enhancing the tension control effect of the motor stator coil winding machine, and reducing the enameled wire tension fluctuation rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present application or the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0039] Figure 1 A flowchart of a method for controlling a micro motor stator coil winding machine according to an embodiment of the present application;

[0040] Figure 2 This is a schematic diagram of the guide needle winding;

[0041] Figure 3 This is a schematic diagram of the enameled wire tension control device. DETAILED DESCRIPTION

[0042] To further illustrate the technical means and effects employed by this application to achieve the intended invention objectives, the following, in conjunction with the accompanying drawings and preferred embodiments, describes in detail a micro-motor stator coil winding machine and its control method, including its specific implementation, structure, features, and effects. In the following description, different references to "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.

[0043] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0044] The specific scheme of a micro motor stator coil winding machine and its control method provided by the present application is described in detail below with reference to the accompanying drawings.

[0045] See also Figure 1 , which shows a flowchart of a micro motor stator coil winding machine control method provided by one embodiment of the present application, the method comprising the following steps:

[0046] Step S1, during the operation of the motor stator coil winding machine, the indirect tension value of the enameled wire at each moment is obtained by the swing angle of the swing arm at each moment; the pay-off linear speed at each moment is obtained by the angular velocity of the pay-off motor at each moment; and the actual measured tension value of the enameled wire at each moment is collected.

[0047] During the winding process of the micro motor stator coil winding machine, the enameled wire passes through the tension control device, passes through the guide needle, and is led out from the guide needle wire mouth, and finally wound on the stator frame. The guide needle moves up and down, and the motor stator square wire frame swings back and forth around the axis. The two movements are performed alternately in sequence, such as Figure 2 As shown, 101 is the square wire frame of the motor stator, 102 is the guide needle, and 103 is the enameled wire.

[0048] The tension control device of the enameled wire includes a pay-off motor, a pay-off wheel, a swing rod, a spring and a guide wheel, such as Figure 3 As shown, 201 is the guide wheel 1, 202 is the pay-off wheel, 203 is the guide wheel 2, 204 is the spring, 205 is the rocker, 206 is the line wheel, 207 is the guide wheel 3, 208 is the motor, is the swing angle of the pendulum arm. The pay-off reel is fixed to the extended shaft of the pay-off motor, which drives its rotation. When the pay-off reel rotates clockwise, the enameled wire is released from the wire source. Furthermore, a rubber ring embedded in the V-shaped groove on the outer edge of the pay-off reel prevents the enameled wire from being pulled out when the reel is stationary. This allows the pay-off motor's rotation to be controlled for active pay-off. By adjusting the pay-off reel's speed, different pay-off speeds can be achieved.

[0049] During the operation of the micro motor stator coil winding machine, a resistance strain sensor is used as a tension sensor to measure the tension of the enameled wire, and the actual tension value of the enameled wire at each sampling moment is obtained. An incremental photoelectric encoder is used as an angle sensor to measure the swing angle of the pendulum and the angular velocity data of the pay-off motor, and the swing angle data of the pendulum and the angular velocity data of the pay-off motor are obtained at each sampling moment.

[0050] The tension fitting value corresponding to the swing angle data is obtained through the swing angle-tension fitting formula, which is used as the indirect tension value of the enameled wire. The product of the angular velocity and the radius of the output shaft of the pay-off motor is calculated as the pay-off linear velocity.

[0051] Among them, the swing angle-tension fitting formula is obtained as follows:

[0052] Since, during the operation of the micro-motor stator coil winding machine, when the swing angle of the pendulum increases, the spring tension increases, and the corresponding enameled wire tension also increases, the swing angle of the pendulum increases and the enameled wire tension has a significant linear relationship. Therefore, the enameled wire tension control device swing angle is tension calibrated, and M groups of pendulum swing angles and corresponding enameled wire tensions are recorded and linearly fitted. The resulting fitting equation is the swing angle-tension fitting formula. The larger the value of M, the more consistent the swing angle-tension fitting formula is with the corresponding relationship between the swing angle of the pendulum and tension. Preferably, in the embodiment of the present application, the value of M is set to 100. As other embodiments of the present application, the implementer can set the value of M according to actual conditions. By substituting the swing angle data collected at each moment into the swing angle-tension fitting formula, the indirect tension value of the enameled wire corresponding to the swing angle data at each moment can be obtained. Among them, the M groups of pendulum swing angles and corresponding enameled wire tension data used to construct the swing angle-tension fitting formula are data measured in advance.

[0053] It should be noted that, for the data acquisition frequency of the tension sensor and the angle sensor, preferably, in the embodiment of the present application, the data acquisition frequency is set to 1 kHz. As other embodiments of the present application, the implementer can set the data acquisition frequency of the tension sensor and the angle sensor according to actual conditions.

[0054] Step S2: Obtain the tension measurement sequence, indirect tension sequence, and pay-off line speed sequence within a preset time period before the current moment; determine the transmission hysteresis value of the indirect tension value of the enameled wire based on the synchronous fluctuation between the tension measurement sequence and the indirect tension sequence under different movement steps.

[0055] During the operation of the micro-motor stator coil winding machine, when the swing angle of the pendulum arm increases, the spring tension increases, and the corresponding enameled wire tension also increases. In addition, the signal of the incremental photoelectric encoder is digital, and its anti-electromagnetic interference capability is strong. However, due to the inertia of mechanical transmission, the indirect tension value has a lag and cannot track instantaneous tension fluctuations in real time. Therefore, this application obtains the transmission lag value of the indirect tension value of the enameled wire of the motor stator coil winding machine in the following way, specifically:

[0056] (1) Get the time before the current moment The actual tension value, indirect tension value and pay-off speed within a certain time period are arranged in ascending order of time to form the actual tension sequence at the current moment. , indirect tension sequence and pay-off line speed sequence; preferably, in the embodiment of the present application, The value of is set to 1min; as other embodiments of this application, the implementer can set it according to the actual situation The value of

[0057] (2) The tension measurement sequence and indirect tension sequence Align according to the time dimension, that is, correspond the actual tension value and the indirect tension value at the same moment;

[0058] Fixed tension measurement sequence , the indirect tension sequence Move to the left according to different moving step lengths to obtain the indirect tension sequence under different moving step lengths;

[0059] For the indirect tension sequence under each moving step, the front end of the sequence exceeds the tension measured sequence The data elements are partially truncated and the missing part at the end is padded with 0, so as to reconcile with the tension measurement sequence. Align, and record the indirect tension sequence after truncation and zero filling under each moving step as the padding sequence under each moving step. Among them, the range of the moving step i is , T is the indirect tension sequence The sequence length.

[0060] This application is for tension measurement sequence and indirect tension sequence The purpose of mobile alignment is to capture the hysteresis of the indirect tension value when the instantaneous tension of the enameled wire fluctuates.

[0061] (3) Taking the i-th padded sequence as an example, the waveform synchronization coefficient between the tension measured sequence at the current moment and the padded sequence under each moving step is calculated. The expression is:

[0062] , where is the waveform synchronization coefficient between the tension measurement sequence at the current moment and the i-th padded sequence; T is the length of the indirect tension sequence at the current moment; is the value of the tth data element in the tension measurement sequence at the current moment; The value of the tth data element in the i-th padded sequence at the current moment.

[0063] The larger the dot product of the tension measurement sequence and the padding sequence at the same position, the greater the possibility that the tension measurement sequence and the alignment sequence are synchronized, and the closer the moving step is to the transmission lag value of the indirect tension value.

[0064] (4) The moving step length is used as the horizontal coordinate and the waveform synchronization coefficient is used as the vertical coordinate to obtain the coordinate points corresponding to the padding sequence under each moving step length. All coordinate points are subjected to nonlinear fitting to obtain a fitting curve of the moving step length-waveform synchronization coefficient. The moving step length corresponding to the minimum value of the horizontal coordinate among all peak points of the fitting curve is used as the transmission hysteresis value of the indirect tension value of the enameled wire of the motor stator coil winding machine, which is recorded as .

[0065] Step S3: Obtain the indirect tension prediction value at a future moment by predicting the indirect tension sequence, and determine the measurement deviation of the tension actual value at the current moment based on the difference between the prediction value corresponding to the transmission lag value and the tension actual value at the current moment.

[0066] Resistive strain gauge tension sensors directly sense the tension load on enameled wires and offer a fast response. They are suitable for reciprocating winding in motor stator coil winding machines, avoiding the inertial lag of the rocker mechanism and enabling timely detection of dynamic tension fluctuations. However, resistive strain gauge tension sensors output analog signals, which are susceptible to electromagnetic interference, affecting measurement stability and generating significant noise. This can distort the measured tension data, disrupt the periodic correlation of the measured tension values, and cause deviations between the measured tension values ​​and the indirect tension values.

[0067] (1) Considering the hysteresis of indirect tension value, this application will use the indirect tension sequence As input to the Exponential Moving Average (EMA) algorithm, forecasting the future The indirect tension value at the moment, where is the transmission lag value; thus the future The indirect tension prediction value at the moment is used as the indirect tension hysteresis correction value at the current moment. The exponential moving average algorithm is a well-known technology, and the specific process will not be repeated here.

[0068] It should be noted that for the indirect tension sequence For prediction, this application only provides one prediction method. There are many existing prediction methods. Implementers can also use other prediction algorithms to obtain indirect tension prediction values. This application does not make specific restrictions.

[0069] (2) Calculate the measured deviation of the actual tension value at the current moment. The expression is:

[0070]

[0071] Where, is the measured deviation of the actual tension value at the current moment, is the actual measured value of tension at the current moment, is the indirect tension hysteresis correction value at the current moment, It is an exponential function with the natural constant e as its base.

[0072] The indirect tension value is corrected by the predicted value at the transmission lag, eliminating the difference between the indirect tension value due to the transmission lag and the actual tension value. The difference between the actual tension value at the current moment and the indirect tension lag correction value is calculated to improve the accuracy of the measurement deviation calculation.

[0073] Step S4, based on the degree of chaos of the data in the neighborhood of each data point in the tension measurement sequence, determine the data points belonging to the reciprocating motion stage of the guide needle in the tension measurement sequence; record the sequence composed of the data points of the reciprocating motion stage of the guide needle that are closest to the current moment and continuous within a preset time length before the current moment as a motion data sequence; based on the correlation between the motion data sequence and the preset tension period sequences, construct the periodic correlation strength of the tension measurement value at the current moment.

[0074] In the micro motor stator coil winding machine, the guide needle moves up and down reciprocatingly once, and the enameled wire is wound around the stator once. The reciprocating movement cycle of the guide needle of the motor stator coil winding machine is recorded as the reciprocating cycle. , the number of motor stators is recorded as N. In the embodiment of the present application, = 100ms, that is, the guide needle moves back and forth once every 0.1s; N = 8. In other embodiments of the present application, the implementer can set it according to the actual situation. and the value of N.

[0075] The operation of a micro-motor stator coil winding machine is divided into a guide needle reciprocating motion phase and a motor replacement phase. Directly dividing the data sequence into reciprocating cycles based on time sequence can easily result in data points from the motor replacement phase within each divided cycle, leading to large errors in calculating cycle correlation. During the guide needle reciprocating motion phase, the guide needle moves up and down to wind all the motor stators in sequence. Since the motor stator is a square wire frame, the winding speed constantly changes, causing fluctuations in the enameled wire tension. Each reciprocating motion of the guide needle causes a complete tension fluctuation in the enameled wire. During the motor replacement phase, the motor is replaced by the motor in the motor stator coil winding machine's main shaft assembly, the guide needle remains stationary, and the enameled wire tension remains stable.

[0076] (1) By determining the degree of data chaos in the neighborhood of each data point in the tension measurement sequence, determine whether each data point belongs to the reciprocating motion stage of the guide needle, specifically:

[0077] For each data point in the tension measurement sequence, take the ath data point as an example, and set the time before the ath data point acquisition moment to The time interval of is taken as the neighborhood of the a-th data point, where is the reciprocating period of the guide needle; the ath data point is the last data point in its neighborhood;

[0078] The standard deviation of the tension measured values ​​of all data points in the neighborhood of the a-th data point is taken as the tension instability value of the a-th data point;

[0079] The OSTU algorithm uses the tension instability values ​​of all data points in the tension measurement sequence as input, outputting a segmentation threshold. Data points with tension instability values ​​greater than the segmentation threshold are considered data points during the guide needle's reciprocating motion phase. The OSTU algorithm is well-known, and the specific process is not detailed here.

[0080] It should be noted that for the threshold segmentation of the unstable tension values ​​of all data points in the tension measurement sequence, this application only provides a threshold segmentation algorithm. There are many existing threshold segmentation algorithms, and implementers can also use other threshold segmentation algorithms to perform threshold segmentation on the unstable tension values ​​of all data points in the tension measurement sequence. This application does not make specific restrictions.

[0081] (2) For the current moment, The time interval within the duration is regarded as the complete reciprocating cycle at the current moment; in the tension measurement sequence, all data points belonging to the reciprocating motion stage of the guide needle in the reciprocating cycle at the current moment are obtained, and the sequence composed of the data points of the reciprocating motion stage of the guide needle closest to the current moment and continuous is regarded as the motion data sequence at the current moment. , which is used to reflect the tension fluctuation information of the enameled wire during the reciprocating motion of the guide needle at the current moment.

[0082] For example, assuming that there are 1 to 13 data points in the reciprocating cycle at the current moment, among which the data points belonging to the reciprocating motion stage of the guide needle are the 1st, 2nd, 3rd, 6th, 7th, 10th, 11th, and 12th data points, then the sequence composed of the 10th, 11th, and 12th data points is the motion data sequence at the current moment.

[0083] (3) Under low noise interference, the present application obtains the actual measured value of the tension of the enameled wire during the reciprocating motion of the guide needle of the prophet, and obtains the actual measured value of the tension in each complete reciprocating cycle of the guide needle from these prophet data to construct each tension cycle sequence; since the number of motor stators is N, the present application obtains N tension cycle sequences. Among them, the arrangement order of the elements in each tension cycle sequence is in ascending time order, and each tension cycle sequence has the enameled wire tension fluctuation information within a complete reciprocating cycle of the guide needle.

[0084] (4) Based on the above analysis, the periodic correlation strength of the measured tension value at the current moment is calculated, and the expression is:

[0085]

[0086] Where, is the periodic correlation strength of the actual tension value at the current moment; N is the number of motor stators, that is, the number of tension period sequences; is the motion data sequence of the actual tension value at the current moment; is the first tension cycle in the nth tension cycle sequence A sequence of data elements, where is a sequence The length of the sequence; The DTW distance is calculated. The calculation of the DTW distance is a well-known technique, and the specific process will not be described in detail.

[0087] The purpose is to intercept a subsequence of the tension cycle sequence with the same length as the motion data sequence, so as to avoid the problem of errors caused by the different tension fluctuation information content between the motion data sequence and the tension cycle sequence when the motor stator coil winding machine just enters the guide needle reciprocating motion stage. The larger the value, the stronger the periodic correlation of the tension fluctuation at the current moment. The bigger.

[0088] Step S5, calculating the interference distortion evaluation value of the actual tension value at the current moment based on the measurement deviation and the periodic correlation strength; constructing the winding looseness of the enameled wire at the current moment based on the changing trend of the pay-off line speed in the time interval of the motion data sequence, and the difference between the actual tension value of the element in the motion data sequence and the preset tension setting value.

[0089] (1) The measured deviation of the actual tension value at the current moment and cycle correlation strength , obtain the interference distortion evaluation value of the tension measurement value at the current moment to evaluate the degree of data distortion caused by electromagnetic interference of the tension measurement value, among which the interference distortion evaluation value is related to the measurement deviation Positively correlated with the strength of the periodic correlation Preferably, in the embodiment of the present application, the ratio of the measured deviation of the tension value at the current moment to the periodic correlation strength is used as the interference distortion evaluation value of the tension value.

[0090] The encoder signal is digital, with strong anti-interference ability and can measure the deviation The larger the value, the greater the deviation between the actual tension value and the indirect tension value after lag correction, and the lower the authenticity of the actual tension value; at the same time, when the period correlation strength The smaller it is, the more seriously the periodic correlation of the actual tension value may be destroyed by noise, the higher the degree of data distortion caused by electromagnetic interference of the actual tension value, and the larger the interference distortion evaluation value.

[0091] (2) The motor stator coil winding machine winds the coil on the circular wire frame. The speed of the enameled wire is almost constant and the tension of the enameled wire is easy to control. However, the speed change of the enameled wire on the square wire frame is much more complicated than that of the circular wire frame. During the reciprocating winding process of the motor stator coil winding machine, when the tension of the enameled wire is small, the faster the pay-off speed, the looser the enameled wire, which is easy to destroy the winding arrangement of the stator coil, resulting in more complicated enameled wire tension fluctuations in subsequent winding.

[0092] Obtain the time interval of the motion data sequence at the current moment, and record the sequence of the line speed of all acquisition moments within the time interval as the line feature sequence at the current moment; use the line feature sequence as the input of the Mann-Kendall test algorithm, and output it as the standardized test statistic The Mann-Kendall test algorithm is a well-known technology, and the specific process will not be described in detail.

[0093] It should be noted that for the trend test of the laying-out feature sequence, this application only provides a trend test method. There are many existing trend test methods, and implementers can also use other trend test algorithms to perform trend tests on the laying-out feature sequence. This application does not make specific restrictions.

[0094] Get the tension setting value of the enameled wire of the micro motor stator coil winding machine In the embodiments of this application, =600g. In other embodiments of the present application, the implementer can set the value.

[0095] Furthermore, the winding looseness of the enameled wire at the current moment is calculated using the expression:

[0096]

[0097] Where, is the winding looseness of the enameled wire at the current moment, Z is the test statistic of the pay-off feature sequence at the current moment, is the sequence length of the motion data sequence at the current moment, is the actual measured value of the tension at the xth data point in the motion data sequence at the current moment, It is an exponential function with the natural constant e as its base.

[0098] It is used to reflect the degree to which the actual tension value of the enameled wire is lower than the safety tension during the reciprocating motion of the guide needle. Used to evaluate the pay-off speed trend of the pay-off motor, The larger the value, the greater the pay-off speed, the more likely the enameled wire is to become loose, and the easier it is to destroy the winding arrangement of the stator coil. The higher the value, the higher the emergency response of the winding tension control at the current moment.

[0099] Step S6, determine the weight based on the winding looseness and the interference distortion evaluation value, and use the weight to weightedly fuse the actual tension measurement at the current moment and the predicted value corresponding to the transmission lag value to obtain the tension correction value at the current moment, and perform tension control of the enameled wire of the motor stator coil winding machine.

[0100] Because the enameled wire winding machine is too loose in the process of winding the enameled wire, it will affect the coil filling factor of the motor stator and reduce the power density and efficiency of the micro motor. The higher the value, the higher the emergency response of the winding tension control at the current moment. In order to minimize the impact on the subsequent enameled wire winding process, based on the looseness of the winding , timely capture the tension load of the enameled wire and adjust the tension of the enameled wire.

[0101] According to the above analysis, the fusion weight of the tension measured value at the current moment is obtained, and the expression is:

[0102] , where is the fusion weight of the tension measured value at the current moment, is the winding looseness of the enameled wire at the current moment, is the interference distortion evaluation value of the actual tension value at the current moment, is the normalization function.

[0103] Interference distortion evaluation value It is used to evaluate the degree of data distortion caused by interference in the actual tension value at the current moment. The smaller the tension value is, the more it can reflect the actual tension load of the enameled wire and the looseness of the winding. Used to reflect the emergency response level of enameled wire winding. The larger the value, the more likely the enameled wire is to be loose. In order to ensure the power density and efficiency of the micromotor, the higher the weight of the actual tension value should be given, the tension load of the enameled wire should be captured in time, the tension of the enameled wire should be adjusted, and the weight should be integrated. The bigger.

[0104] Furthermore, the tension correction value at the current moment is calculated as follows:

[0105] , where is the tension correction value at the current moment, is the fusion weight of the tension measured value at the current moment, is the actual measured value of tension at the current moment, It is the indirect tension hysteresis correction value at the current moment.

[0106] The tension of the enameled wire of the motor stator coil winding machine is corrected to eliminate the transmission lag of the indirect measurement method, improve the anti-interference ability of the direct measurement method, and reflect the tension load characteristics of the enameled wire of the motor stator coil winding machine.

[0107] Calculate the tension correction value b and the tension setting value The difference is recorded as the tension difference The role of the integral term in the PID control algorithm is to eliminate the residual error and improve the control accuracy. When the motor stator coil winding machine just enters the guide needle reciprocating motion stage, the tension difference Larger, using the integral term will continue to accumulate these larger differences.

[0108] This application uses a PID controller to adjust the tension of the enameled wire. In order to avoid the above-mentioned integral problem, a PID tension control method with integral separation is proposed, specifically: setting a difference threshold u, when the tension difference is When the difference value is greater than or equal to the threshold value u, the integral term of the PID algorithm is canceled to reduce the overshoot and oscillation of the tension control of the motor stator coil winding machine and improve the tension stability of the enameled wire; when the tension ... When the difference value is less than the threshold value u, the integral operation of the PID algorithm is introduced to eliminate the tension residual and improve the control accuracy of the motor stator coil winding machine. Preferably, in the embodiment of the present application, the difference threshold value u is set to the tension setting value. For the setting of parameters in the PID control algorithm, this application uses the Ziegler-Nichols parameter tuning method to obtain them.

[0109] It should be noted that this application only provides a PID parameter setting method. There are many existing PID parameter setting methods. Implementers can also use other parameter setting methods to set the parameters in the PID control algorithm. This application does not make specific restrictions.

[0110] Based on the same inventive concept as the above method, an embodiment of the present application also provides a micro motor stator coil winding machine, which is applied to the above-mentioned micro motor stator coil winding machine control method, and the control of the motor stator coil winding machine is implemented using the above-mentioned micro motor stator coil winding machine control method.

[0111] In summary, the embodiment of the present application provides a control method for a micro motor stator coil winding machine, which determines the transmission hysteresis value of the indirect tension value of the enameled wire through the synchronous fluctuation between the actual tension measurement sequence and the indirect tension sequence under different moving step sizes, performs hysteresis correction on the indirect tension value, and considers the tension cycle correlation strength during the operation stage of the motor stator coil winding machine to comprehensively evaluate the interference distortion degree of the actual tension measurement value, thereby further improving the reliability and stability of the tension control system of the motor stator coil winding machine and reducing the winding quality problems caused by measurement errors and system hysteresis; obtains the enameled wire tension value through the change trend of the pay-off line speed and the difference between the actual tension measurement value and the set value. The looseness of the wire winding is combined with the interference distortion degree to construct a fusion weight, and the importance of the actual tension measurement value is comprehensively analyzed; the actual tension measurement value and the indirect tension prediction value are weighted and fused to obtain the tension correction value, eliminate the transmission lag of the indirect measurement method, improve the anti-interference ability of the direct measurement method, improve the accuracy of the enameled wire tension measurement value, and avoid the problem of excessive tension causing the enameled wire to break or too little tension causing the coil to loosen in the tension control; in the process of controlling the enameled wire tension of the motor stator coil winding machine through the tension correction value, the present application provides an integral separation PID control method, which dynamically adjusts the control strategy according to the size of the tension difference between the tension correction value and the set value. When the tension difference is large, the integral term is canceled to reduce the overshoot and oscillation of the enameled wire tension control of the motor stator coil winding machine. When the difference is small, the integral term is introduced to eliminate the residual error of the enameled wire tension control, thereby improving the accuracy of the motor stator coil winding machine tension control, enhancing the tension control effect of the motor stator coil winding machine, and reducing the enameled wire tension fluctuation rate.

[0112] It should be noted that the order in which the embodiments of the present application are presented is for illustrative purposes only and does not necessarily represent the superiority or inferiority of the embodiments. Furthermore, the above descriptions are of specific embodiments of the present application. Furthermore, the processes depicted in the accompanying drawings do not necessarily require the specific order or sequential sequence shown to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0113] The various embodiments in this application are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments.

[0114] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A micro motor stator coil winding machine control method, characterized in that: The method comprises the following steps: During the operation of the motor stator coil winding machine, the indirect tension value of the enameled wire at each moment is obtained through the swing angle of the swing arm at each moment; the pay-off linear speed at each moment is obtained through the angular velocity of the pay-off motor at each moment; and the actual measured tension value of the enameled wire at each moment is collected; Obtain the tension measurement sequence, indirect tension sequence and pay-off line speed sequence within a preset time period before the current moment; Calculate the product of each element in the tension measurement sequence and the corresponding element in the indirect tension sequence under any movement step, record it as the first product, calculate the sum of all the first products of the indirect tension sequence under any movement step, record it as the waveform synchronization coefficient; The moving step length is used as the horizontal coordinate and the waveform synchronization coefficient is used as the vertical coordinate to obtain the coordinate points corresponding to the indirect tension sequence under each moving step length. In the fitting curve obtained by performing nonlinear fitting on all coordinate points, the moving step length corresponding to the minimum value of the horizontal coordinate among all peak points is used as the transmission hysteresis value of the indirect tension value of the enameled wire; By predicting the indirect tension sequence, the indirect tension prediction value at the future moment is obtained, and the measurement deviation of the tension actual value at the current moment is determined based on the difference between the prediction value corresponding to the transmission lag value and the tension actual value at the current moment; The data points in the tension measurement sequence belonging to the reciprocating motion phase of the guide needle are determined based on the degree of data chaos within the neighborhood of each data point in the tension measurement sequence; the sequence consisting of the data points of the reciprocating motion phase of the guide needle that are closest to the current moment and continuous within a preset time period before the current moment is recorded as a motion data sequence; the periodic correlation strength of the tension measurement value at the current moment is constructed based on the correlation between the motion data sequence and each preset tension period sequence; Calculating an interference distortion assessment value of the actual tension measurement value at the current moment based on the measurement deviation and the periodic correlation strength; constructing a winding looseness of the enameled wire at the current moment based on a change trend of the pay-off line speed within the time interval of the motion data sequence and a difference between the actual tension measurement value of the element in the motion data sequence and a preset tension setting value; The weight is determined based on the winding looseness and the interference distortion evaluation value, and the actual tension measurement at the current moment and the predicted value corresponding to the transmission lag value are weightedly fused through the weight to obtain the tension correction value at the current moment, and the tension of the enameled wire of the motor stator coil winding machine is controlled.

2. A micro motor stator coil winding machine control method according to claim 1, characterized in that: The process of obtaining the measurement deviation of the actual tension value at the current moment is as follows: The transmission hysteresis value is recorded as , get the future The indirect tension prediction value at the moment is used as the indirect tension hysteresis correction value at the current moment; The measured deviation of the tension value at the current moment is recorded as , The expression is: , where is the actual measured value of tension at the current moment, is the indirect tension hysteresis correction value at the current moment, It is an exponential function with the natural constant e as its base.

3. A micro motor stator coil winding machine control method according to claim 1, characterized in that: The process of acquiring the data points belonging to the reciprocating motion phase of the guide needle in the tension measurement sequence is as follows: The duration of the reciprocating cycle of the guide needle of the motor stator coil winding machine is recorded as For any data point in the tension measurement sequence, the time before the acquisition moment of any data point is as the neighborhood of any data point; and taking the standard deviation of the tension measured values ​​of all data points in the neighborhood of any data point as the tension instability value of any data point; The segmentation threshold of the tension instability value of all data points in the tension measurement sequence is obtained by using a threshold segmentation algorithm; The data points where the tension instability value is greater than the segmentation threshold are regarded as the data points of the reciprocating motion stage of the guide needle.

4. A micro motor stator coil winding machine control method according to claim 1, characterized in that: The expression of the periodic correlation strength of the tension measured value at the current moment is: Where, is the periodic correlation strength of the actual tension value at the current moment; N is the number of preset tension cycle sequences; is the motion data sequence at the current moment; It is the first tension cycle in the nth preset tension cycle sequence. A sequence of data elements, where is a sequence The length of the sequence; To calculate the DTW distance.

5. A micro motor stator coil winding machine control method according to claim 1, characterized in that: The interference distortion evaluation value of the actual tension measurement value at the current moment is: the ratio of the measurement deviation of the actual tension measurement value at the current moment to the periodic correlation strength.

6. A micro motor stator coil winding machine control method as claimed in claim 4, characterized in that: The process of obtaining the winding looseness of the enameled wire at the current moment is: The sequence of the line speeds at all moments within the time interval of the motion data sequence at the current moment is recorded as the line feature sequence at the current moment; the line feature sequence is used as the input of the trend test algorithm, and the output is the standardized test statistic, recorded as ; Get the preset enameled wire tension setting value, recorded as ; The winding looseness of the enameled wire at the current moment is recorded as , The expression is: Where, is the sequence length of the motion data sequence at the current moment, is the actual measured value of the tension at the xth data point in the motion data sequence at the current moment, It is an exponential function with the natural constant e as its base.

7. A micro motor stator coil winding machine control method as claimed in claim 2, characterized in that: The tension correction value at the current moment is obtained to control the tension of the enameled wire of the motor stator coil winding machine, specifically: The normalized value of the ratio of the winding looseness to the interference distortion evaluation value at the current moment is used as the fusion weight of the tension measurement value at the current moment; the tension correction value at the current moment is calculated based on the tension measurement value at the current moment, the indirect tension hysteresis correction value and the fusion weight; The difference between the current tension correction value and the preset tension setting value is recorded as the tension difference; When the tension of the enameled wire is adjusted by the PID controller, when the tension difference is greater than or equal to the preset difference threshold, the integral term of the PID algorithm is canceled; When the tension difference is less than the preset difference threshold, the integral operation of the PID algorithm is introduced to control the tension of the motor stator coil winding machine.

8. A micro motor stator coil winding machine control method according to claim 7, characterized in that: The expression of the tension correction value is: , where is the tension correction value at the current moment, is the fusion weight of the tension measured value at the current moment, is the actual measured value of tension at the current moment, It is the indirect tension hysteresis correction value at the current moment.

9. A micro motor stator coil winding machine, characterized in that: The control of the motor stator coil winding machine is achieved by using the method described in any one of claims 1 to 8.

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