Teacup conveyor rail motor speed regulation circuit and speed regulation method based on PWM control

Abstract

The present invention relates to the technical field of tea set conveying control, and in particular to a speed regulation circuit and a speed regulation method for a tea cup conveying track motor based on PWM control. The present invention draws a torque change curve of a motor, obtains curve parameters through the torque change curve, determines whether there is an abnormal phenomenon in the on-track distribution state of tea cups on the current tea conveying track based on the curve parameters, calculates the track switching influence characterization coefficient of the tea cups in the switching process of different tea conveying tracks through the curve parameters and the tea cup size parameters, so as to determine whether it is necessary to regulate the speed of a conveying motor corresponding to a switched tea conveying track corresponding to the current tea conveying track, and adjusts the input PWM signal of the conveying motor corresponding to the switched tea conveying track by determining a speed regulation execution time period, thereby realizing a combined analysis of the tea cup conveying state stability and the characteristics of the tea cups themselves, and selecting a suitable speed regulation time to regulate the motor speed, thereby improving the stability of tea cup conveying and improving the customer's experience of using tea.

Description

Technical Field

[0001] The invention relates to the technical field of tea set conveying control, and in particular to a tea cup conveying track motor speed regulation circuit and a speed regulation method based on PWM control. Background Art

[0002] Tea art culture is a beautiful business card of Chinese traditional culture and also an exquisite art form. The elegant rituals in tea art performances are an important part of tea art culture. Tea artists need to pour tea into teacups with various appearances. Service staff constantly deliver teacups filled with fragrant tea to customers, which is not conducive to the continuity of tea art performances. Therefore, targeted improvements and integration of automatic teacup conveying control and tea art culture performances have become the current exploration direction of technical personnel.

[0003] The teacup conveyor track is a carefully designed control system that can automatically transport teacups from the tea artist to the customers and return the idle teacups to the tea artist. The teacup conveyor system can be composed of an electric transmission device, a sensor, a control system, and a specially designed conveying channel. Through the specific conveying motor joint control technology, the posture control and smooth conveyance of irregular number of teacups in the tea drinking scene can be achieved, which is an important problem that needs to be solved urgently in the current scene.

[0004] For example, China Patent Publication No.: CN110963256A, the invention discloses a conveyor adaptive speed control method, including: obtaining the no-load torque value and full-load torque value of the variable frequency motor; obtaining the minimum speed and maximum speed of the variable frequency motor, dividing 0-100% into n intervals from small to large, each interval corresponding to a speed; calculating the proportion of the difference between the actual torque value and the no-load torque value in the interval, and quantifying it to obtain a torque quantization value; calculating the volume quantization value according to the torque quantization value; determining the interval where the volume quantization value is located, and obtaining the speed corresponding to the interval as the target speed. The conveyor adaptive speed control method of the invention utilizes the positive correlation between the torque value and the load weight and the speed, and adjusts the given speed of the inverter according to the torque value, so that the running speed of the motor is adaptively adjusted according to the load weight.

[0005] The prior art still has the following problems:

[0006] The existing technology does not take into account the special tea-drinking scenario, where the real-time number of tea cups on the tea delivery track fluctuates irregularly due to fluctuations in the number of customers and differences in their tea usage. The fluctuation in the number of tea cups makes it easy for the tea cups to squeeze each other at the switching position of the tea delivery track, and the spilled tea greatly affects the customer experience. Summary of the invention

[0007] To this end, the present invention provides a teacup conveyor track motor speed control circuit and speed control method based on PWM control to overcome the problems that the prior art cannot combine and analyze the stability of the teacup conveying state and the characteristics of the teacup itself, and cannot select the appropriate speed control time for motor speed control.

[0008] To achieve the above object, the present invention provides a teacup conveyor track motor speed regulation method based on PWM control, comprising:

[0009] In response to the normal operation signal of the tea delivery track, based on the terminal torque of the conveying motor of the current tea delivery track, a torque variation curve of the terminal torque varying with time is drawn;

[0010] Acquiring curve parameters based on the torque variation curve, and determining whether there is an abnormality in the distribution state of tea cups on the current tea delivery track based on the curve parameters;

[0011] Wherein, the curve parameters include the slopes corresponding to a number of data points on the torque variation curve;

[0012] In response to the abnormality of the distribution state of the tea cups on the track, the track switching influence characterization coefficient of the tea cups in the switching process of different tea delivery tracks is calculated based on the curve parameters and the tea cup size parameters to determine whether it is necessary to adjust the speed of the conveying motor corresponding to the switched tea delivery track corresponding to the current tea delivery track;

[0013] The teacup size parameters include the height of the teacup and the diameter of the bottom of the teacup;

[0014] In response to the need to adjust the speed of the conveying motor, within the speed adjustment execution time period, the input PWM signal of the conveying motor corresponding to the switched tea conveying track is adjusted, wherein the PWM signal includes a duty cycle;

[0015] Wherein, the speed regulation execution time period is determined based on the curve parameters of the torque change curve.

[0016] Furthermore, the step of obtaining curve parameters includes:

[0017] Determining a plurality of data points on the torque variation curve;

[0018] Determine a curve segment of a preset length including the data point based on the data point;

[0019] Obtaining coordinates of two endpoints of the curve segment, and determining a slope of a line connecting the two endpoints based on the coordinates;

[0020] The slope is determined as the slope corresponding to the data point.

[0021] Furthermore, the process of determining whether there is an abnormality in the distribution state of tea cups on the current tea delivery track includes:

[0022] Calculating the slope standard deviation of a plurality of data points based on the slopes corresponding to the data points, and comparing the slope standard deviation with a preset slope standard deviation threshold;

[0023] If the slope standard deviation is greater than the slope standard deviation threshold, it is determined that there is an abnormality in the distribution state of the tea cups on the current tea delivery track.

[0024] Furthermore, the process of calculating the track switching impact characterization coefficient also includes:

[0025] Determine a maximum slope value based on slopes corresponding to a plurality of data points on the torque variation curve;

[0026] The ratio of the height of the teacup to the diameter of the bottom surface of the teacup is calculated based on the teacup size parameters.

[0027] Furthermore, the track switching impact characterization coefficient is calculated according to the following formula:

[0028] ;

[0029] Wherein, T is the coefficient representing the impact of track switching, k max is the maximum slope value, k0 is the preset slope reference value, Rs is the ratio of the height of the teacup to the diameter of the bottom of the teacup, Rs0 is the preset ratio reference value, μ is the slope weight coefficient, η is the ratio weight coefficient, and e is a constant.

[0030] Furthermore, the process of determining whether it is necessary to adjust the speed of the conveying motor corresponding to the switched tea delivery track corresponding to the current tea delivery track is as follows:

[0031] Comparing the track switching impact characterization coefficient with a preset track switching impact characterization coefficient threshold;

[0032] If the track switching impact characterization coefficient is greater than the track switching impact characterization coefficient threshold, it is determined that the conveying motor corresponding to the switched tea delivery track corresponding to the current tea delivery track needs to be speed-regulated.

[0033] Furthermore, the step of determining the speed regulation execution time period includes:

[0034] Obtaining slopes corresponding to a plurality of data points on the torque variation curve;

[0035] Filter characteristic data points based on the slopes corresponding to the data points, and determine the time corresponding to the characteristic data points;

[0036] Determine the time interval between the moments corresponding to each characteristic data point, and divide the moments whose time interval is less than a preset time interval reference value into the same speed regulation execution time period.

[0037] Furthermore, the process of screening feature data points is:

[0038] Compare the slope corresponding to the data point with a preset slope reference value;

[0039] If the slope is greater than the slope reference value, it is determined that the data point is screened as a characteristic data point.

[0040] Furthermore, the process of adjusting the input PWM signal includes:

[0041] The PWM signal input to the conveying motor corresponding to the switched tea delivery track is adjusted based on the track switching impact characterization coefficient, and the duty cycle in the PWM signal is positively correlated with the track switching impact characterization coefficient.

[0042] Furthermore, the present invention also provides a teacup conveyor track motor speed regulation circuit based on PWM control, comprising:

[0043] A microcontroller to generate a PWM signal;

[0044] A driving amplifier is connected to the microcontroller circuit and is used to convert the PWM signal into voltage and current.

[0045] Compared with the prior art, the beneficial effect of the present invention lies in that the present invention plots a torque variation curve of the terminal torque varying with time, obtains curve parameters through the torque variation curve, determines whether there is an abnormal phenomenon in the on-track distribution state of tea cups on the current tea delivery track based on the curve parameters, calculates the track switching influence characterization coefficient of the tea cups in the switching process of different tea delivery tracks through the curve parameters and the tea cup size parameters, so as to determine whether it is necessary to adjust the speed of the conveying motor corresponding to the switched tea delivery track corresponding to the current tea delivery track, adjusts the input PWM signal of the conveying motor corresponding to the switched tea delivery track by determining the speed regulation execution time period, thereby realizing a combined analysis of the stability of the tea cup conveying state and the characteristics of the tea cups themselves, and selecting the appropriate speed regulation time for motor speed regulation, thereby improving the stability of tea cup conveying and improving the customer's tea experience.

[0046] In particular, the present invention determines whether there is any abnormality in the on-track distribution state of tea cups on the current tea delivery track through the curve parameters of the torque change curve. Those skilled in the art will understand that in actual tea-using scenarios, due to fluctuations in the number of customers and differences in customers' tea usage, the number of tea cups on the tea delivery track may fluctuate continuously, resulting in different distribution distances between tea cups on the tea delivery track with a fixed distance. Tea cups with closely spaced distances may be squeezed and bumped against each other due to the shaking of the tea cups during the switching process of the tea delivery track. The present invention obtains the terminal torque of the conveying motor, and monitors the dynamic changes of the number of tea cups on the tea delivery track in real time through the changes in the terminal torque. The more tea cups on the tea delivery track, the greater the terminal torque of the conveying motor. Thus, the stability of the tea cup conveying state is analyzed.

[0047] In particular, the present invention calculates the coefficient of influence of track switching of tea cups in different tea delivery track switching processes through curve parameters and teacup size parameters. It can be understood by those skilled in the art that in actual tea-using scenarios, the real-time number of tea cups transported by each section of the conveying track fluctuates. The larger the slope value corresponding to the torque change curve, the more rapid and short-term increase in the number of tea cups on the tea delivery track occurs. The more tea cups there are, the more crowded the distribution of the tea cups on the tea delivery track with a fixed distance is, and the more likely they are to be squeezed and collided with each other at the switching position of the tea delivery track. Similarly, the larger the ratio of the height of the tea cup to the diameter of the bottom surface of the tea cup, the higher the center of gravity of the tea cup and the smaller the stable contact area provided by the bottom surface, and the more likely they are to be squeezed and collided with each other at the switching position of the tea delivery track due to unstable center of gravity. The present invention combines the calculation of curve parameters and teacup size parameters to realize the combined analysis of the stability of the teacup conveying state and the characteristics of the teacup itself, and quantifies the influence of the number and the morphological characteristics of the teacup conveying that are difficult to characterize.

[0048] In particular, the present invention determines the speed regulation execution time period through the curve parameters of the torque change curve. In the actual tea-using scenario, the real-time conveying number of tea cups for each conveying track changes. The slope of the torque change curve is greater than the preset reference value, indicating that the number of tea cups on the tea delivery track at the corresponding moment is increasing. The present invention screens out the moments when the number of tea cups increases, and determines the time interval between the moments. The time interval is less than the preset reference value, indicating that the number of tea cups on the tea delivery track continues to increase during this time period. The present invention determines the time period when the number of tea cups continues to increase as the speed regulation execution time period, realizes the selection of appropriate speed regulation timing for motor speed regulation, improves the stability of tea cup transportation, and improves the customer's tea-using experience.

[0049] In particular, the present invention adjusts the input PWM signal to the conveying motor corresponding to the switched tea delivery track. Those skilled in the art can understand that by appropriately increasing the running speed of the conveying motor corresponding to the switched tea delivery track, the distance between the tea cups at the switching position of the tea delivery track and the tea cups on the tea delivery track before the switching can be quickly increased, thereby avoiding mutual squeezing and collision of tea cups with shaking postures, improving the stability of tea cup conveyance, and improving customers' tea-drinking experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 This is a step diagram of a method for regulating the speed of a teacup conveying track motor based on PWM control according to an embodiment of the present invention;

[0051] Figure 2 A diagram showing the steps of obtaining curve parameters according to an embodiment of the present invention;

[0052] Figure 3 The present invention is a logic flow chart for determining whether there is an abnormality in the distribution state of tea cups on the current tea delivery track according to an embodiment of the present invention;

[0053] Figure 4 A diagram of the steps for determining a speed regulation execution time period according to an embodiment of the present invention. DETAILED DESCRIPTION

[0054] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0055] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0056] It should be noted that in the description of the present invention, terms such as "upper" and "inner" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is only for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0057] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0058] See also Figure 1 As shown, it is a step diagram of a teacup conveyor rail motor speed regulation method based on PWM control according to an embodiment of the present invention. A teacup conveyor rail motor speed regulation method based on PWM control according to the present invention comprises:

[0059] Step S100, in response to a normal operation signal of the tea delivery track, based on the terminal torque of the conveying motor of the current tea delivery track, a torque variation curve of the terminal torque varying with time is drawn;

[0060] Step S200, obtaining curve parameters based on the torque change curve, and determining whether there is an abnormality in the distribution state of tea cups on the current tea delivery track based on the curve parameters;

[0061] Wherein, the curve parameters include the slopes corresponding to a number of data points on the torque variation curve;

[0062] Step S300, in response to the abnormality of the distribution state of the tea cups on the track, the track switching influence characterization coefficient of the tea cups in the switching process of different tea delivery tracks is calculated based on the curve parameters and the tea cup size parameters, so as to determine whether it is necessary to adjust the speed of the conveying motor corresponding to the switched tea delivery track corresponding to the current tea delivery track;

[0063] The teacup size parameters include the height of the teacup and the diameter of the bottom of the teacup;

[0064] Step S400, in response to the need to adjust the speed of the conveying motor, within the speed adjustment execution time period, adjusting the input PWM signal of the conveying motor corresponding to the switched tea conveying track, wherein the PWM signal includes a duty cycle;

[0065] Wherein, the speed regulation execution time period is determined based on the curve parameters of the torque change curve.

[0066] Specifically, in the embodiment of the present invention, the conveying motor of the current tea delivery track operates stably and has no abnormal fault alarm, and can send out a normal operation signal of the tea delivery track. This is well known to those skilled in the art and will not be elaborated here.

[0067] Specifically, the present invention does not limit the method for obtaining the terminal torque of the conveying motor. The torque at the load end of the conveying motor can be monitored by a load torque sensor. The load torque sensor is a commonly used sensor in the industrial field and will not be described in detail here.

[0068] Specifically, the present invention does not limit the method of adjusting the input PWM signal. Those skilled in the art can understand that the duty cycle of the PWM signal is the ratio of the high level duration to the entire cycle time. The operating speed of the conveying motor can be changed by adjusting the duty cycle of the PWM signal. This is a prior art and will not be repeated here.

[0069] Specifically, see Figure 2 As shown, it is a step diagram of obtaining curve parameters in an embodiment of the present invention, and the step of obtaining curve parameters includes:

[0070] Step S201, determining a number of data points on the torque variation curve;

[0071] Step S202, determining a curve segment of a preset length including the data point based on the data point;

[0072] Step S203, obtaining the coordinates of the two endpoints of the curve segment, and determining the slope of the line connecting the two endpoints based on the coordinates;

[0073] Step S204: determine the slope as the slope corresponding to the data point.

[0074] In an embodiment of the present invention, the curve segment of the preset length can be determined based on the time corresponding to the data point, the time period including the time corresponding to the data point is determined, and the curve segment corresponding to the time period is determined as the curve segment of the preset length.

[0075] Specifically, see Figure 3 As shown, it is a logic flow chart of determining whether there is an abnormality in the distribution state of tea cups on the current tea delivery track according to an embodiment of the present invention. The process of determining whether there is an abnormality in the distribution state of tea cups on the current tea delivery track includes:

[0076] Based on the slope corresponding to the data point, calculate the slope standard deviation k of several data points c , the slope standard deviation k c The slope standard deviation threshold k is c0 Make a comparison;

[0077] If the slope standard deviation k c Less than or equal to the slope standard deviation threshold k c0 , it is determined that there is no abnormality in the distribution of tea cups on the current tea delivery track;

[0078] If the slope standard deviation k c Greater than the slope standard deviation threshold k c0 , it is determined that the distribution of tea cups on the current tea delivery track is abnormal;

[0079] In the embodiment of the present invention, the slope standard deviation threshold k c0 The value of is determined based on the preset length of the curve segment, and the slope standard deviation threshold k c0The value range of is [1,2], and the unit is Nm / min. Preferably, when the length of the time period corresponding to the curve segment is 1 minute, the slope standard deviation threshold k c0 =1.5Nm / min.

[0080] Specifically, the present invention determines whether there is any abnormality in the on-track distribution state of tea cups on the current tea delivery track through the curve parameters of the torque change curve. Those skilled in the art will understand that in actual tea-using scenarios, due to fluctuations in the number of customers and differences in customers' tea usage, the number of tea cups on the tea delivery track may fluctuate continuously, resulting in different distribution distances between tea cups on the tea delivery track with a fixed distance. Tea cups with closely spaced distances may be squeezed and bumped against each other due to the shaking of the tea cups during the switching process of the tea delivery track. The present invention obtains the terminal torque of the conveying motor, and monitors the dynamic changes of the number of tea cups on the tea delivery track in real time through the changes in the terminal torque. The more tea cups on the tea delivery track, the greater the terminal torque of the conveying motor. Thus, the stability of the tea cup conveying state is analyzed.

[0081] Specifically, the process of calculating the track switching impact characterization coefficient also includes:

[0082] The maximum slope k is determined based on the slopes corresponding to several data points on the torque variation curve. max ;

[0083] The ratio Rs of the height h of the teacup to the bottom diameter d of the teacup is calculated based on the teacup size parameters, where Rs=h / d.

[0084] Specifically, the track switching impact characterization coefficient is calculated according to the following formula:

[0085] ;

[0086] Wherein, T is the coefficient representing the impact of track switching, k max is the maximum slope value, k0 is the preset slope reference value, Rs is the ratio of the height of the teacup to the diameter of the bottom of the teacup, Rs0 is the preset ratio reference value, μ is the slope weight coefficient, η is the ratio weight coefficient, μ+η=1, and e is a constant.

[0087] In the embodiment of the present invention, the slope reference value k0=δ×k c0 , δ is the slope reference value factor, and the value range of δ is [1.2,1.25]. The ratio reference value Rs0 is calculated in advance. The ratio of the height of tea cups of different specifications to the bottom diameter of the tea cups is determined in advance, and the average value of the ratio is calculated, and the average value of the ratio is determined as the ratio reference value Rs0.

[0088] The slope weight coefficient μ and the ratio weight coefficient η are selected by technical personnel in this field based on the degree of influence of the slope in historical data and the ratio of the height of the teacup to the diameter of the bottom of the teacup on the calculation results. Preferably, the slope weight coefficient μ can be set to 0.4 and the ratio weight coefficient η can be set to 0.6.

[0089] Specifically, the present invention calculates the coefficient of influence of track switching of tea cups in different tea delivery track switching processes through curve parameters and teacup size parameters. It can be understood by those skilled in the art that in actual tea-using scenarios, the real-time number of tea cups transported by each section of the conveying track fluctuates. The larger the slope value corresponding to the torque change curve, the more rapid and short-term increase in the number of tea cups on the tea delivery track occurs. The more tea cups there are, the more crowded the distribution of the tea cups on the tea delivery track with a fixed distance is, and the easier it is for them to squeeze and collide with each other at the switching position of the tea delivery track. Similarly, the larger the ratio of the height of the tea cup to the diameter of the bottom surface of the tea cup, the higher the center of gravity of the tea cup and the smaller the stable contact area provided by the bottom surface, and the easier it is for them to squeeze and collide with each other at the switching position of the tea delivery track due to unstable center of gravity. The present invention combines the curve parameters and the teacup size parameters for calculation, realizes the combined analysis of the stability of the teacup conveying state and the characteristics of the teacup itself, and quantifies the influence of the number and the morphological characteristics of the teacup conveying that are difficult to characterize.

[0090] Specifically, the process of determining whether it is necessary to adjust the speed of the conveying motor corresponding to the switched tea delivery track corresponding to the current tea delivery track is as follows:

[0091] Comparing the track switching impact characterization coefficient T with a preset track switching impact characterization coefficient threshold T0;

[0092] If the track switching influence characterization coefficient T is less than or equal to the track switching influence characterization coefficient threshold T0, it is determined that there is no need to adjust the speed of the conveying motor corresponding to the switched tea delivery track corresponding to the current tea delivery track;

[0093] If the track switching impact characterization coefficient T is greater than the track switching impact characterization coefficient threshold T0, it is determined that the conveying motor corresponding to the switched tea delivery track corresponding to the current tea delivery track needs to be speed-regulated.

[0094] In the embodiment of the present invention, the value range of the track switching impact characterization coefficient threshold T0 is [1.1, 1.15].

[0095] Specifically, see Figure 4 As shown, it is a step diagram of determining a speed regulation execution time period according to an embodiment of the present invention, and the step of determining the speed regulation execution time period includes:

[0096] Step S401, obtaining slopes corresponding to a number of data points on the torque variation curve;

[0097] Step S402, screening characteristic data points based on the slopes corresponding to the data points, and determining the time corresponding to the characteristic data points;

[0098] Step S403, determining the time intervals between the moments corresponding to the characteristic data points, and classifying the moments whose time intervals are smaller than a preset time interval reference value into the same speed regulation execution time period.

[0099] In the embodiment of the present invention, the preset time interval reference value can be adjusted by those skilled in the art according to the actual situation of the device. Preferably, the value range of the time interval reference value is [2,5], and the unit is min.

[0100] Specifically, the present invention determines the speed regulation execution time period through the curve parameters of the torque change curve. In the actual tea-using scenario, the real-time conveying number of tea cups on each conveying track changes. The slope of the torque change curve is greater than the preset reference value, indicating that the number of tea cups on the tea delivery track at the corresponding moment is increasing. The present invention screens out the moments when the number of tea cups increases, and determines the time interval between the moments. The time interval is less than the preset reference value, indicating that the number of tea cups on the tea delivery track continues to increase during this time period. The present invention determines the time period when the number of tea cups continues to increase as the speed regulation execution time period, realizes the selection of the appropriate speed regulation opportunity for motor speed regulation, improves the stability of tea cup transportation, and improves the customer's tea-using experience.

[0101] Specifically, the process of screening feature data points is:

[0102] Compare the slope k corresponding to the data point with the preset slope reference value k0;

[0103] If the slope k is less than or equal to the slope reference value k0, determining not to filter the data point;

[0104] If the slope k is greater than the slope reference value k0, it is determined that the data point is screened as a characteristic data point.

[0105] Specifically, the process of adjusting the input PWM signal includes:

[0106] Based on the track switching impact characterization coefficient, the conveying motor corresponding to the switched tea delivery track is adjusted to input a PWM signal, and the duty cycle in the PWM signal is positively correlated with the track switching impact characterization coefficient T.

[0107] Specifically, the present invention adjusts the input PWM signal to the conveying motor corresponding to the switched tea delivery track. Those skilled in the art will understand that by appropriately increasing the running speed of the conveying motor corresponding to the switched tea delivery track, the spacing distance between the tea cups at the switching position of the tea delivery track and the tea cups on the tea delivery track before the switching can be rapidly increased, thereby avoiding mutual squeezing and collision of tea cups with shaking postures, improving the stability of tea cup conveyance, and improving customers' tea-drinking experience.

[0108] Specifically, the present invention also provides a teacup conveyor track motor speed regulation circuit based on PWM control, comprising:

[0109] A microcontroller to generate a PWM signal;

[0110] A driving amplifier is connected to the microcontroller circuit and is used to convert the PWM signal into voltage and current.

[0111] Specifically, the present invention does not limit the specific structure of the microcontroller. Preferably, it can be a single-chip microcomputer with a built-in timer. This is a prior art and will not be described in detail here.

[0112] Specifically, the present invention does not limit the specific structure of the driving amplifier. Preferably, it can be an IGBT driver, which is well known to those skilled in the art and will not be described in detail here.

[0113] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

[0114] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A teacup conveyor track motor speed regulation method based on PWM control, characterized in that: include: In response to the normal operation signal of the tea delivery track, based on the terminal torque of the conveying motor of the current tea delivery track, a torque variation curve of the terminal torque varying with time is drawn; Acquiring curve parameters based on the torque variation curve, and determining whether there is an abnormality in the distribution state of tea cups on the current tea delivery track based on the curve parameters; Wherein, the curve parameters include the slopes corresponding to a number of data points on the torque variation curve; In response to the abnormality of the distribution state of the tea cups on the track, the track switching influence characterization coefficient of the tea cups in the switching process of different tea delivery tracks is calculated based on the curve parameters and the tea cup size parameters to determine whether it is necessary to adjust the speed of the conveying motor corresponding to the switched tea delivery track corresponding to the current tea delivery track; The teacup size parameters include the height of the teacup and the diameter of the bottom of the teacup; The process of calculating the track switching impact characterization coefficient also includes: Determine a maximum slope value based on slopes corresponding to a plurality of data points on the torque variation curve; Calculating the ratio of the height of the teacup to the diameter of the bottom surface of the teacup based on the teacup size parameters; In response to the need to adjust the speed of the conveying motor, within the speed adjustment execution time period, the input PWM signal of the conveying motor corresponding to the switched tea conveying track is adjusted, wherein the PWM signal includes a duty cycle; Wherein, the speed regulation execution time period is determined based on the curve parameters of the torque change curve.

2. The teacup conveyor track motor speed regulation method based on PWM control according to claim 1 is characterized in that: The steps to obtain curve parameters include: Determining a plurality of data points on the torque variation curve; Determine a curve segment of a preset length including the data point based on the data point; Obtaining coordinates of two endpoints of the curve segment, and determining a slope of a line connecting the two endpoints based on the coordinates; The slope is determined as the slope corresponding to the data point.

3. The teacup conveyor track motor speed regulation method based on PWM control according to claim 2 is characterized in that: The process of determining whether there is an abnormality in the distribution state of tea cups on the current tea delivery track includes: Calculating the slope standard deviation of a plurality of data points based on the slopes corresponding to the data points, and comparing the slope standard deviation with a preset slope standard deviation threshold; If the slope standard deviation is greater than the slope standard deviation threshold, it is determined that there is an abnormality in the distribution state of the tea cups on the current tea delivery track.

4. The teacup conveyor track motor speed regulation method based on PWM control according to claim 1 is characterized in that: The track switching impact characterization coefficient is calculated according to the following formula: ； Wherein, T is the coefficient representing the impact of track switching, k max is the maximum slope value, k0 is the preset slope reference value, Rs is the ratio of the height of the teacup to the diameter of the bottom of the teacup, Rs0 is the preset ratio reference value, μ is the slope weight coefficient, η is the ratio weight coefficient, and e is a constant.

5. The teacup conveyor track motor speed regulation method based on PWM control according to claim 4 is characterized in that: The process of determining whether it is necessary to adjust the speed of the conveying motor corresponding to the switched tea delivery track corresponding to the current tea delivery track is as follows: Comparing the track switching impact characterization coefficient with a preset track switching impact characterization coefficient threshold; If the track switching impact characterization coefficient is greater than the track switching impact characterization coefficient threshold, it is determined that the conveying motor corresponding to the switched tea delivery track corresponding to the current tea delivery track needs to be speed-regulated.

6. The teacup conveyor track motor speed regulation method based on PWM control according to claim 1 is characterized in that: The step of determining the speed regulation execution time period comprises: Obtaining slopes corresponding to a plurality of data points on the torque variation curve; Filter characteristic data points based on the slopes corresponding to the data points, and determine the time corresponding to the characteristic data points; Determine the time interval between the moments corresponding to each characteristic data point, and divide the moments whose time interval is less than a preset time interval reference value into the same speed regulation execution time period.

7. The teacup conveyor track motor speed regulation method based on PWM control according to claim 6 is characterized in that: The process of screening feature data points is: Compare the slope corresponding to the data point with a preset slope reference value; If the slope is greater than the slope reference value, it is determined that the data point is screened as a characteristic data point.

8. The teacup conveyor track motor speed regulation method based on PWM control according to claim 1 is characterized in that: The process of adjusting the input PWM signal includes: The PWM signal input to the conveying motor corresponding to the switched tea delivery track is adjusted based on the track switching impact characterization coefficient, and the duty cycle in the PWM signal is positively correlated with the track switching impact characterization coefficient.

9. A teacup conveyor track motor speed control circuit based on PWM control, applied to the teacup conveyor track motor speed control method based on PWM control according to any one of claims 1 to 8, characterized in that: include: A microcontroller to generate a PWM signal; A driving amplifier is connected to the microcontroller circuit and is used to convert the PWM signal into voltage and current.

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