Method and apparatus for compensating hall sensor offset signal for moving magnet linear motor

Abstract

A method for correcting an offset signal of a Hall sensor of a moving magnet linear motor and an offset signal correction device are disclosed. The offset signal correction method may include the steps of collecting a Hall sensor signal value from a Hall sensor of a stator for controlling the position of a mover of a moving magnet linear motor, calculating a first offset signal value based on the Hall sensor signal value, and correcting the offset signal value by calculating a second offset signal value based on the first offset signal value and the Hall sensor signal value.

Description

Technology Field

[0001] The following disclosure relates to a Hall sensor offset signal correction technique for a moving magnet linear motor. Background Technology

[0002] Moving magnet linear motors are widely used in linear transport systems requiring high speed, high precision, and flexible transport. Information regarding the position of the mover is essential for controlling the position and torque of the mover from the stator; while expensive optical sensors may be used for this purpose, low-cost Hall sensors are commonly used in transport systems with many movers and stators. When Hall sensors are used, position values ​​are obtained by interpolating the sensor output, which is in the form of a sinusoidal wave with a 90-degree phase difference, to ensure positional precision. At this time, differences in the amplitude and offset of the two sinusoidal waves occur depending on the sensor assembly tolerances and circuit component deviations of the stator, as well as the magnet assembly tolerances of the mover. Since these amplitudes and offsets lead to positional errors, correction for these amplitudes and offsets is necessary to acquire precise positional information. means of solving the problem

[0003] A method for correcting an offset signal of a Hall sensor according to one embodiment may include: a step of collecting a Hall sensor signal value from a Hall sensor of a stator for controlling the position of a mover of a moving magnet linear motor; a step of calculating a first offset signal value based on the Hall sensor signal value; and a step of correcting an offset signal value by calculating a second offset signal value based on the first offset signal value and the Hall sensor signal value.

[0004] The step of calculating the second offset signal value may include the step of calculating the slope based on the first offset signal value, and the step of calculating the second offset signal value based on at least one of the calculated slope, the first offset signal value, the time value, and the position value of the mover.

[0005] The step of calculating the second offset signal value above is the k-th minimum value of the Hall sensor signal value (k is a natural number) (m k The time value (t) corresponding to ) 2k ) and the k-th maximum value of the above Hall sensor signal value (M k The time value (t) corresponding to ) 2k-1 The above k-th maximum value (M) for the difference between ) k The first offset signal value (d) corresponding to ) 2k ) and the k-1th minimum value (m k-1 The first offset signal value (d) corresponding to ) 2k-1 A step of calculating the ratio of the difference between ) as the slope; the time value (t) corresponding to the k-th minimum value at the current time value (t) 2k Subtract ) and the difference (T) between the time value at which the maximum or minimum value occurred and the time value at which the Hall sensor signal value is updated. lag Multiplying the sum of ) by the above slope and the above k-th maximum value (M k The first offset signal value (d) corresponding to ) 2k It may include a step of calculating the second offset signal value by adding ).

[0006] The step of calculating the second offset signal value above is the k-th minimum value of the Hall sensor signal value (k is a natural number) (m k The angle (θ) corresponding to ) 2k ) and the k-th maximum value of the above Hall sensor signal value (M k The angle (θ) corresponding to ) 2k-1 The above k-th maximum value (M) for the difference between ) k The first offset signal value (d) corresponding to ) 2k ) and the k-1th minimum value (m k-1 The first offset signal value (d) corresponding to ) 2k-1 A step of calculating the ratio of the difference between ) as the slope; the angle (θ) corresponding to the k-th minimum value at the current angle (θ) 2k Subtract ) and the difference (θ) between the angle at which the maximum or minimum value occurs and the angle at which the Hall sensor signal value is updated. lagMultiplying the sum of ) by the above slope and the above k-th maximum value (M k The first offset signal value (d) corresponding to ) 2k The method includes the step of calculating the second offset signal value by adding ), and each angle value may correspond to the position value of the mover.

[0007] The step of calculating the first offset signal value may include the step of calculating the first offset signal value based on the Hall sensor signal value using a min-max algorithm.

[0008] The method may further include a step of calculating the position value of the mover based on the Hall sensor signal value and the second offset signal value.

[0009] The second offset signal value may be a linearly corrected version of the first offset signal value.

[0010] An offset signal correction device for a Hall sensor according to one embodiment may include a Hall sensor signal value measuring unit that collects a Hall sensor signal value from a Hall sensor of a stator for controlling the position of a mover of a moving magnet linear motor; and a calculation unit that corrects an offset signal value by calculating a first offset signal value based on the Hall sensor signal value and calculating a second offset signal value based on the first offset signal value and the Hall sensor signal value.

[0011] The calculation unit above can calculate a slope based on the first offset signal value and calculate the second offset signal value based on at least one of the calculated slope, the first offset signal value, the time value, and the position value of the mover.

[0012] The above calculation unit is the k-th minimum value of the Hall sensor signal value (k is a natural number) (m k The time value (t) corresponding to ) 2k ) and the k-th maximum value of the above Hall sensor signal value (M k The time value (t) corresponding to ) 2k-1The above k-th maximum value (M) for the difference between ) k The first offset signal value (d) corresponding to ) 2k ) and the k-1th minimum value (m k-1 The first offset signal value (d) corresponding to ) 2k-1 Calculate the ratio of the difference between ) as the slope, and the time value (t) corresponding to the k-th minimum value at the current time value (t) 2k Subtract ) and the difference (T) between the time value at which the maximum or minimum value occurred and the time value at which the Hall sensor signal value is updated. lag Multiplying the sum of ) by the above slope and the above k-th maximum value (M k The first offset signal value (d) corresponding to ) 2k The second offset signal value can be calculated by adding ).

[0013] The above calculation unit is the k-th minimum value of the Hall sensor signal value (k is a natural number) (m k The angle (θ) corresponding to ) 2k ) and the k-th maximum value of the above Hall sensor signal value (M k The angle (θ) corresponding to ) 2k-1 The above k-th maximum value (M) for the difference between ) k The first offset signal value (d) corresponding to ) 2k ) and the k-1th minimum value (m k-1 The first offset signal value (d) corresponding to ) 2k-1 Calculate the ratio of the difference between ) as the slope, and the angle (θ) corresponding to the k-th minimum value at the current angle (θ) 2k Subtract ) and the difference (θ) between the angle at which the maximum or minimum value occurs and the angle at which the Hall sensor signal value is updated. lag Multiplying the sum of ) by the above slope and the above k-th maximum value (M k The first offset signal value (d) corresponding to ) 2k The second offset signal value is calculated by adding ), and each angle value can correspond to the position value of the mover.

[0014] The above calculation unit can calculate the first offset signal value based on the Hall sensor signal value using a minimum-maximum algorithm.

[0015] The above calculation unit can calculate the position value of the mover based on the Hall sensor signal value and the second offset signal value.

[0016] The second offset signal value may be a linearly corrected version of the first offset signal value. Effects of the invention

[0017] According to one embodiment, the accurate position of a mover can be estimated by accurately correcting the offset that reduces the accuracy of the mover's position estimation, and accordingly, the position of the mover can be controlled more precisely.

[0018] According to one embodiment, when using a relatively low-cost Hall sensor, the position of the mover can be accurately estimated, thereby improving cost efficiency.

[0019] According to one embodiment, the offset signal of a Hall sensor can be corrected based on information that can be easily obtained. Brief explanation of the drawing

[0020] FIG. 1 is a flowchart illustrating an offset signal correction method according to one embodiment. FIG. 2 is a diagram illustrating the configuration of a moving magnet linear motor system according to one embodiment. Figure 3 is a graph showing the Hall sensor signal value and electrical angle. Figure 4 is a graph showing the error in the electrical angle due to the offset error. Figure 5 is a graph showing the error in the electrical angle due to the difference in amplitude. FIG. 6 is a diagram illustrating the measurement of maximum and minimum values ​​according to one embodiment. FIG. 7 is a graph showing the waveform of a Hall sensor signal value of a linear motor in which the offset signal value changes linearly according to one embodiment. FIG. 8 is a graph illustrating the result of linear correction according to one embodiment. FIG. 9 is a graph for explaining an offset signal correction method according to one embodiment. Figure 10 is a graph showing the difference between the offset signal value calculated through the min-max algorithm and the actual offset signal value. FIG. 11 is a diagram illustrating the configuration of an offset signal correction device according to one embodiment. Specific details for implementing the invention

[0021] Specific structural or functional descriptions of the embodiments are disclosed for illustrative purposes only and may be modified and implemented in various forms. Accordingly, actual implementations are not limited to the specific embodiments disclosed, and the scope of this specification includes modifications, equivalents, or substitutions included in the technical concept described by the embodiments.

[0022] Terms such as "first" or "second" may be used to describe various components, but these terms should be interpreted solely for the purpose of distinguishing one component from another. For example, the first component may be named the second component, and similarly, the second component may be named the first component.

[0023] When it is stated that a component is "connected" to another component, it should be understood that it may be directly connected to or coupled with that other component, or that there may be other components in between.

[0024] Singular expressions include plural expressions unless the context clearly indicates otherwise. In this document, phrases such as “A or B,” “at least one of A and B,” “at least one of A or B,” “A, B or C,” “at least one of A, B and C,” and “at least one of A, B, or C” may each include any one of the items listed together with the corresponding phrase, or all possible combinations thereof. In this specification, terms such as “comprising” or “having” are intended to designate the existence of the described feature, number, step, action, component, part, or combination thereof, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0025] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this specification.

[0026] As used herein, the term "module" may include a unit implemented in hardware, software, or firmware, and may be used interchangeably with terms such as logic, logic block, component, or circuit. A module may be a component formed integrally, or a minimum unit of said component or a part thereof that performs one or more functions. For example, according to one embodiment, a module may be implemented in the form of an application-specific integrated circuit (ASIC).

[0027] As used in this document, the term "part" refers to a software or hardware component, such as an FPGA or ASIC, that performs certain roles. However, "part" is not limited to software or hardware. "Part" may be configured to reside in an addressable storage medium or configured to operate one or more processors. For example, "part" may include components such as software components, object-oriented software components, class components, and task components, as well as processes, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functions provided within the components and "parts" may be combined into a smaller number of components and "parts" or further separated into additional components and "parts." Furthermore, components and "parts" may be implemented to operate one or more CPUs within a device or secure multimedia card. Additionally, '~part' may include one or more processors.

[0028] Hereinafter, embodiments will be described in detail with reference to the attached drawings. In the description with reference to the attached drawings, identical components are given the same reference numeral regardless of the drawing number, and redundant descriptions thereof will be omitted.

[0029] The offset signal correction device described herein may provide an offset signal correction method for improving the accuracy of calculating the position value of a mover to control the position and torque of a mover in a linear magnet motor of a linear transport system comprising a plurality of movers and a plurality of stators. The offset signal correction device may calculate an offset signal value based on a Hall sensor signal value, and may perform correction on the calculated offset signal value to reduce the error between the calculated offset signal value and the actual offset signal value. The offset signal correction device may perform linear correction on the offset signal value based on a min-max algorithm and the slope of the offset signal value. The mover described herein may also be referred to as a moving magnet, and the stator may also be referred to as a stationary magnet.

[0030] FIG. 1 is a flowchart illustrating an offset signal correction method according to one embodiment.

[0031] The embodiments described herein may be embodiments for a linear transport system comprising a large number of movers and a large number of stators. In the embodiments described herein, because there are many movers and stators, Hall sensors, which are relatively inexpensive compared to optical sensors, may be used. In one embodiment, information regarding the position of the mover may be required to control at least one of the position (or position value) and torque of the mover of the moving magnet linear motor in the stator. In one embodiment, the Hall sensor signal may be output in the form of a sinusoidal wave having a phase difference of 90 degrees. The offset signal correction device described herein may interpolate the Hall sensor signal in the form of a sinusoidal wave having a phase difference of 90 degrees to obtain an accurate and precise position. To obtain the position or position value of the mover, the offset signal correction device may perform correction on the difference between at least one of the amplitude and offset (or offset signal or offset signal value) of two sinusoidal waves based on the sensor assembly tolerance of the stator, the deviation of circuit elements, and the magnet assembly tolerance of the mover. Through this, the offset signal correction device may obtain the accurate position of the stator or facilitate obtaining the accurate position of the stator. The Hall sensor signal or Hall sensor signal value described in this specification may also be referred to as the Hall sensor output or Hall sensor output value. In one embodiment, a moving magnet linear motor may include a plurality of movers and a plurality of stators. The length of the stator or the stators may be smaller than, equal to, or larger than the length of the mover or the movers.

[0032] Referring to FIG. 1, in step (110), the offset signal correction device can collect Hall sensor signal values ​​from the Hall sensor of the stator for controlling the position of the mover of the moving magnet linear motor. The offset signal correction device can perform preprocessing on the collected Hall sensor signal values ​​by removing measurement noise. The Hall sensor signal values ​​described below may represent Hall sensor signal values ​​from which signal noise has been removed.

[0033] The offset signal correction device can calculate a first offset signal value based on the Hall sensor signal value in step (120). The offset signal correction device can calculate the first offset signal value based on the Hall sensor signal value using a min-max algorithm. Here, the min-max algorithm may also be referred to as the Min-Max algorithm. According to the min-max algorithm, the amplitude can be calculated as shown in the equation below.

[0034]

[0035] In addition, according to the min-max algorithm, the offset signal value can be calculated as shown in the equation below.

[0036]

[0037] In mathematical formulas 1 and 2, the maximum value represents the maximum value of the Hall sensor signal value, and the minimum value represents the minimum value of the Hall sensor signal value.

[0038] In step (130), the offset signal correction device can correct the offset signal value by calculating a second offset signal value based on the first offset signal value and the Hall sensor signal value. Here, the second offset signal value may be a linearly corrected version of the first offset signal value. The offset signal correction device can calculate a slope based on the first offset signal value. The offset signal correction device can calculate the second offset signal value based on at least one of the calculated slope, the first offset signal value, the time value, and the position value of the mover. The position value of the mover used to calculate the second offset signal value may correspond to the position value of the mover calculated at a time past the current time. More specifically, the second offset signal value ( The formula for calculating ) can be the same as mathematical formula 3.

[0039]

[0040] Based on the above equation, the offset signal correction device [corrects] the k-th minimum value (k is a natural number) of the Hall sensor signal value (m k The time value (t) corresponding to ) 2k ) and the k-th maximum value of the Hall sensor signal (M k The time value (t) corresponding to ) 2k-1 k-th maximum value for the difference between ) (M k The first offset signal value (d) corresponding to ) 2k ) and the k-1th minimum value (m k-1 The first offset signal value (d) corresponding to ) 2k-1 The ratio of the difference between ) can be calculated as the slope. The offset signal correction device [calculates] the time value (t) corresponding to the k-th minimum value at the current time value (t). 2k Subtract ) and the difference (T) between the time value at which the maximum or minimum value occurred and the time value at which the Hall sensor signal value is updated. lag Multiply the sum of ) by the slope and the k-th maximum value (M k The first offset signal value (d) corresponding to ) 2kThe second offset signal value can be calculated by adding ).

[0041] Since time and angle can be represented synchronously in mathematical equation 3, the second offset signal value ( The formula for calculating ) can also be the same as mathematical formula 4.

[0042]

[0043] The offset signal correction device is the k-th minimum value of the Hall sensor signal value (k is a natural number) (m k The angle (θ) corresponding to ) 2k ) and the k-th maximum value of the Hall sensor signal (M k The angle (θ) corresponding to ) 2k-1 k-th maximum value for the difference between ) (M k The first offset signal value (d) corresponding to ) 2k ) and the k-1th minimum value (m k-1 The first offset signal value (d) corresponding to ) 2k-1 The ratio of the difference between ) can be calculated as the slope. The offset signal correction device [calculates] the angle (θ₀) corresponding to the k-th minimum value at the current angle (θ₀). 2k Subtract ) and the difference (θ) between the angle at which the maximum or minimum value occurs and the angle at which the Hall sensor signal value is updated. lag Multiply the sum of ) by the slope and the k-th maximum value (M k The first offset signal value (d) corresponding to ) 2k The second offset signal value can also be calculated by adding ). Here, the angle (θ 2k ), angle(θ 2k-1 Each angle value, including at least one of ) and angle (θ), may correspond to the position value of the mover calculated immediately prior. Here, θ may represent the position value of the mover calculated immediately prior. In the description of this specification, angle, angle value, and electric angle may be replaced with position and position value, and vice versa.

[0044] According to an embodiment, the offset signal correction device may calculate the position value of a mover based on a Hall sensor signal value and a second offset signal value. The offset signal correction device can correct the offset signal value of a Hall sensor signal value by replacing the first offset signal value, which is an offset signal value corrected only based on a minimum-maximum algorithm of the Hall sensor signal value, with the second offset signal value. The offset signal correction device can measure the accurate position value of a mover based on the second offset signal value, which is a linearly corrected first offset signal value.

[0045] FIG. 2 is a diagram illustrating the configuration of a moving magnet linear motor system according to one embodiment.

[0046] Referring to FIG. 2, a moving magnet linear motor system may include a moving magnet linear motor. The moving magnet linear motor may include a mover (210) and a stator (220, 230). When acquiring electrical angle information required for control using a Hall sensor, a pair of Hall sensors (240, 250, 260, 270) may be placed at each end of the stator (220, 230) so that an offset signal correction device can collect Hall sensor signal values ​​having a phase difference of 90 degrees. In other words, a pair of Hall sensors (240) may be placed at one end of the stator (220), and another pair of Hall sensors (250) may be placed at the other end of the stator (220). Likewise, a pair of Hall sensors (260) may be placed at one end of the stator (230), and another pair of Hall sensors (270) may be placed at the other end of the stator (230). The number of Hall sensors placed on one side of the stator is not limited to the description in this specification and the examples in the drawings. Also, the number of movers (210) and stators (220, 230) shown in FIG. 2 is limited to examples for illustrating the drawings, and in the embodiments described in this specification, the moving magnet linear motor may include a plurality of movers and a plurality of stators.

[0047] Figure 3 is a graph showing the Hall sensor signal value and electrical angle.

[0048] Referring to FIG. 3, FIG. 3(a) can represent Hall sensor signal values. Each Hall sensor signal value can have a phase difference of 90 degrees from each other. Additionally, FIG. 3(b) can represent electrical angles. The electrical angle of a moving magnet linear motor can represent the value of the angle formed with respect to the center of two points on the circumference of a rotary motor, which is the value actually measured.

[0049] Figure 4 is a graph showing the error in the electrical angle due to the offset error.

[0050] Referring to FIG. 4, FIG. 4(a) may represent Hall sensor signal values. Each Hall sensor signal value may have a phase difference of 90 degrees from one another. Additionally, FIG. 4(b) may represent electrical angles. The description of electrical angles may be the same as the description in FIG. 3. FIG. 4(c) may represent electrical angle errors caused by the error between the calculated offset signal value and the actual offset signal value. That is, if an error occurs in the offset signal value, an error may also occur in the electrical angle. Therefore, the offset signal correction device described in this specification can calculate a corrected offset signal value by performing linear correction on the offset signal value in which an error has occurred, thereby preventing errors in the electrical angle and the position value of the mover.

[0051] Figure 5 is a graph showing the error in the electrical angle due to the difference in amplitude.

[0052] Referring to FIG. 5, FIG. 5(a) may represent Hall sensor signal values, and each Hall sensor signal value may have a phase difference of 90 degrees from each other. Additionally, FIG. 5(b) may represent electrical angles. The description of electrical angles may be the same as the description in FIG. 3. FIG. 5(c) may represent the error in electrical angles due to amplitude differences.

[0053] FIG. 6 is a diagram illustrating the measurement of maximum and minimum values ​​according to one embodiment.

[0054] FIG. 6 may be a graph representing the measurement and updating of maximum and minimum values ​​for a max-max algorithm. Theta (610) may represent the position value of a mover as Theta and may represent an electrical angle. State (620) may represent the state value of a state machine for measuring the maximum and minimum values ​​of the electrical angle. Uc (630) may represent a Hall sensor signal value including an offset signal value having a cosine wave shape, and Us (640) may represent a Hall sensor signal value including an offset signal value having a sinusoidal wave shape. The offset signal correction device may determine the maximum or minimum value for a predetermined area before and after the location where the maximum and minimum values ​​occur in order to obtain the maximum and minimum values ​​from the electrical angle (or position value) containing the error, and may update the maximum or minimum value when it goes out of the predetermined area. For example, the offset signal correction device can determine the maximum or minimum value at an electrical angle of approximately 30 degrees before and after the location where the maximum and minimum values ​​occur, and update the maximum or minimum value when it deviates from that predetermined area. In Fig. 6, Max c and Max s represents the maximum value and Min c and Min s It can represent the minimum value.

[0055] FIG. 7 is a graph showing the waveform of a Hall sensor signal value of a linear motor in which the offset signal value changes linearly according to one embodiment.

[0056] In a linear conveying system using a linear motor, unlike conventional rotary motors, the offset signal value of the Hall sensor signal value may change as shown in FIG. 7 due to end effects, such as magnetic flux leakage at both ends of the magnetic plate of the mover. In FIG. 7, reference number (710) may represent the Hall sensor signal value of phase B. Reference number (720) may represent the Hall sensor signal value of phase A. Reference number (730) may represent the calculated amplitude of the Hall sensor of phase A. Reference number (740) may represent the calculated amplitude of the Hall sensor of phase B. Reference number (750) may represent the offset signal value of the Hall sensor of phase A calculated. Reference number (760) may represent the offset signal value of the Hall sensor of phase B calculated. Here, phase A and phase B may be used to distinguish Hall sensor signal values ​​having a phase difference of a predetermined amount (e.g., 90 degrees).

[0057] FIG. 8 is a graph illustrating the result of linear correction according to one embodiment.

[0058] Referring to FIG. 8, reference number (810) may represent the calculation error (or error) of the mover's position value calculated when correction to the offset signal value is performed using only the min-max algorithm. Reference number (830) may represent the calculation error (or error) of the mover's position value calculated when the offset signal value is accurately known. Additionally, reference number (820) may represent the calculation error (or error) of the mover's position value calculated when the offset signal value is corrected by the offset signal correction method described herein. Reference number (820) in Equation 3 When applied, the calculation error of the mover's position value can be indicated. The calculation error of reference number (820) can be reduced to within 10% compared to the case where only the min-max algorithm is applied. The offset signal correction device can perform the offset signal correction method described in this specification by adding a linear correction term to the min-max algorithm to correct the error between the calculated offset signal value and the actual offset signal value. That is, the offset signal correction device can perform correction of the offset signal value more accurately than correcting the offset signal value using only the min-max algorithm by additionally performing linear correction to the min-max algorithm to correct the error between the calculated offset signal value and the actual offset signal value.

[0059] Seeing that reference number (820) is much closer to reference number (830) than reference number (810), it can be seen that the position value of the mover calculated based on the offset signal value corrected by the offset signal correction device is more similar to the actual position value of the mover than the position value of the mover calculated based on the offset signal value without linear correction. That is, it can be seen that the position value of the mover calculated based on the offset signal value corrected based on the min-max algorithm and additionally linearly corrected by the offset signal correction device is more accurate than the position value of the mover calculated based on the offset signal value where only the min-max algorithm is performed and linear correction is not performed. The offset signal correction device can accurately calculate the position value of the mover by performing the offset signal correction method described in this specification. More specifically, the area for obtaining the maximum value or the minimum value When so, the difference between the time value at which the maximum or minimum value occurs and the time value at which the actual Hall sensor signal value is updated is It can be. However, the offset signal correction device By correcting The calculation error can be made zero by applying it. When applied, the calculation error can be 0, as in reference number (830).

[0060] FIG. 9 is a graph for explaining an offset signal correction method according to one embodiment.

[0061] Referring to FIG. 9, the horizontal axis of the graph may represent time, and the vertical axis of the graph may represent the Hall sensor signal value. Reference number (905) is the k-th maximum value (M) of the Hall sensor signal value described in FIG. 1. k It can represent ). Also, the reference number (910) is the k+1th maximum value (M) of the Hall sensor signal value. k+1 It can represent ). Reference number (915) is the k-1th minimum value (m) of the Hall sensor signal value. k-1 It can represent ), and the reference number (920) is the k-th minimum value (m) of the Hall sensor signal value. k It can represent ). Reference number (925) is the k-th maximum value (M k The first offset signal value (d) corresponding to ) 2k It can represent ), and the reference number (935) is the k-th minimum value (m) of the Hall sensor signal value. k The first offset signal value (d) corresponding to ) 2k+1 It can represent ).

[0062] First offset signal value (d 2k )(925) is the k-th maximum value of the Hall sensor signal (M k )(905) and the k-1th minimum value of the Hall sensor signal value (m k-1 It can be calculated by adding )(915) and dividing the result by 2. The first offset signal value (d 2k+1 )(935) is the k-th maximum value of the Hall sensor signal (M k )(905) and the k-th minimum value of the Hall sensor signal (m k It can be calculated by adding )(920) and dividing the result by 2. M k (905) This M k(905) corresponding time value (t 2k-1 Time point t when moving out of the maximum value acquisition region including )(940) 2k-1 + Δ t 2k-1 In this case, the first offset signal value is d 2k It can be updated to (925). Likewise, m k (920) is m k (920) corresponding time value (t 2k Time point t when moving out of the minimum value acquisition region including )(945) 2k + Δ t 2k The first offset signal value is d 2k+1 It can be updated to (935). The current time value t is t 2k-1 + Δ t 2k-1 < t < t 2k + Δ t 2k while d 2k (925) can be used as the first offset signal value. Also, the current time value t is t 2k + Δ t 2k < t < t 2k+1 + Δ t 2k+1 while d 2k+1 (935) can be used as the first offset signal value. t 2k+1 M is reference number (950) k+1 It can be a time value corresponding to (910). That is, t 2k-1 + Δ t 2k-1 < t < t 2k + Δ t 2k During the time period, the first offset signal value is d 2k (925) and t 2k + Δ t 2k < t < t 2k+1 + Δ t 2k+1 During the time period, the first offset signal value is d 2k+1 (935) It could be

[0063] Figure 10 is a graph showing the difference between the offset signal value calculated through the min-max algorithm and the actual offset signal value. Referring to Figure 10, the vertical axis may represent the offset signal value and the horizontal axis may represent time.

[0064] The offset signal values ​​(1030, 1040) corrected solely based on the min-max algorithm without linear correction can be updated, for example, twice in one cycle. Since the maximum and minimum values ​​of the most recently acquired Hall sensor signal values ​​are used in this process, the error between the actual offset signal values ​​(1010, 1020) that increase or decrease linearly and the offset signal values ​​(1030, 1040) calculated based on the min-max algorithm may be as shown in FIG. 10. The offset signal correction device can reduce the error shown in FIG. 10 by performing linear correction based on the slope of the offset signal values ​​in addition to the min-max algorithm.

[0065] FIG. 11 is a diagram illustrating the configuration of an offset signal correction device according to one embodiment.

[0066] The offset signal correction device (1100) of FIG. 11 may correspond to the offset signal correction device described in the present specification. The offset signal correction device (1100) may include a Hall sensor signal value measuring unit (1110) and a calculation unit (1120).

[0067] The Hall sensor signal value measuring unit (1110) can collect Hall sensor signal values ​​from the Hall sensor of the stator for controlling the position of the mover of the moving magnet linear motor.

[0068] The calculation unit (1120) can correct the offset signal value by calculating a first offset signal value based on the Hall sensor signal value and calculating a second offset signal value based on the first offset signal value and the Hall sensor signal value. The calculation unit (1120) can calculate a slope based on the first offset signal value and calculate a second offset signal value based on at least one of the calculated slope, the first offset signal value, the time value, and the position value of the mover.

[0069] The calculation unit (1120) calculates the k-th minimum value of the Hall sensor signal value (k is a natural number) (m k The time value (t) corresponding to ) 2k ) and the k-th maximum value of the Hall sensor signal (M k The time value (t) corresponding to ) 2k-1 k-th maximum value for the difference between ) (M k The first offset signal value (d) corresponding to ) 2k ) and the k-1th minimum value (m k-1 The first offset signal value (d) corresponding to ) 2k-1 Calculate the ratio of the difference between ) as the slope, and the time value (t) corresponding to the k-th minimum value at the current time value (t) 2k Subtract ) and the difference (T) between the time value at which the maximum or minimum value occurred and the time value at which the Hall sensor signal value is updated. lag Multiply the sum of ) by the slope and the k-th maximum value (M k The first offset signal value (d) corresponding to ) 2k The second offset signal value can be calculated by adding ).

[0070] Since each angle value corresponds to the position value of the mover, the calculation unit (1120) calculates the k-th minimum value (k is a natural number) (m of the Hall sensor signal value k The angle (θ) corresponding to ) 2k ) and the k-th maximum value of the Hall sensor signal (M k The angle (θ) corresponding to ) 2k-1 k-th maximum value for the difference between ) (M k The first offset signal value (d) corresponding to )2k ) and the k-1th minimum value (m k-1 The first offset signal value (d) corresponding to ) 2k-1 Calculate the ratio of the difference between ) as the slope, and the angle (θ) corresponding to the k-th minimum value at the current angle (θ) 2k Subtract ) and the difference (θ) between the angle at which the maximum or minimum value occurs and the angle at which the Hall sensor signal value is updated. lag Multiply the sum of ) by the slope and the k-th maximum value (M k The first offset signal value (d) corresponding to ) 2k The second offset signal value can also be calculated by adding ).

[0071] The calculation unit (1120) can calculate a first offset signal value based on a Hall sensor signal value using a minimum-maximum algorithm, and can calculate a position value of a mover based on the Hall sensor signal value and a second offset signal value.

[0072] The embodiments described above may be implemented as hardware components, software components, and / or combinations of hardware and software components. For example, the devices, methods, and components described in the embodiments may be implemented using a general-purpose computer or a special-purpose computer, such as, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA), a programmable logic unit (PLU), a microprocessor, or any other device capable of executing and responding to instructions. The processing unit may execute an operating system (OS) and software applications executed on said operating system. Additionally, the processing unit may access, store, manipulate, process, and generate data in response to the execution of the software. For ease of understanding, the processing unit may be described as being used as a single unit, but those skilled in the art will understand that the processing unit may include multiple processing elements and / or multiple types of processing elements. For example, the processing unit may include multiple processors or one processor and one controller. In addition, other processing configurations, such as parallel processors, are also possible.

[0073] Software may include computer programs, code, instructions, or a combination of one or more of these, and may configure a processing unit to operate as desired or instruct the processing unit independently or collectively. Software and / or data may be permanently or temporarily embodied in any type of machine, component, physical device, virtual equipment, computer storage medium, or device so as to be interpreted by the processing unit or to provide instructions or data to the processing unit. Software may be distributed over networked computer systems and may be stored or executed in a distributed manner. Software and data may be stored on computer-readable recording media.

[0074] The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer-readable medium. The computer-readable medium may store program instructions, data files, data structures, etc., either alone or in combination, and the program instructions recorded on the medium may be those specifically designed and configured for the embodiment or may be those known and available to those skilled in the art of computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tapes; optical recording media such as CD-ROMs and DVDs; magneto-optical media such as floptical disks; and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, and flash memory. Examples of program instructions include machine code, such as that generated by a compiler, as well as high-level language code that can be executed by a computer using an interpreter, etc.

[0075] The hardware device described above may be configured to operate as one or more software modules to perform the operation of the embodiment, and vice versa.

[0076] Although the embodiments have been described above with reference to the limited drawings, those skilled in the art can apply various technical modifications and variations based thereon. For example, suitable results may be achieved even if the described techniques are performed in a different order than described, and / or if the components of the described system, structure, device, circuit, etc. are combined or assembled in a form different from described, or replaced or substituted by other components or equivalents.

[0077] Therefore, other implementations, other embodiments, and equivalents to the claims also fall within the scope of the claims set forth below.

Claims

Claim 1 A method for correcting an offset signal of a Hall sensor, comprising: a step of collecting a Hall sensor signal value from a Hall sensor of a stator for controlling the position of a mover of a moving magnet linear motor; a step of calculating a first offset signal value based on the Hall sensor signal value; and a step of correcting an offset signal value by calculating a second offset signal value based on the first offset signal value and the Hall sensor signal value, wherein the step of calculating the first offset signal value includes a step of calculating the first offset signal value by calculating the average between the maximum value of the Hall sensor signal value and the minimum value of the Hall sensor signal value using a min-max algorithm, and the step of correcting an offset signal value by calculating the second offset signal value includes a step of calculating the slope of the first offset signal value based on the first offset signal value; a step of calculating the second offset signal value based on at least one of the calculated slope, the first offset signal value, and the position value of the mover; and a step of correcting the offset signal value by replacing the first offset signal value with the second offset signal value. Claim 2 delete Claim 3 In claim 1, the step of calculating the slope comprises the k-th minimum value of the Hall sensor signal value (k is a natural number) (m k The time value (t) corresponding to ) 2k ) and the k-th maximum value of the above Hall sensor signal value (M k The time value (t) corresponding to ) 2k-1 The above k-th maximum value (M) for the difference between ) k The first offset signal value (d) corresponding to ) 2k ) and the k-1th minimum value (m k-1 The first offset signal value (d) corresponding to ) 2k-1 The method includes a step of calculating the ratio of the difference between ) as the slope, wherein the second offset signal value is a time value (t) corresponding to the k-th minimum value at the current time value (t). 2k Subtract ) and the difference (T) between the time value at which the maximum or minimum value occurred and the time value at which the Hall sensor signal value is updated. lag Multiplying the sum of ) by the above slope and the above k-th maximum value (M k The first offset signal value (d) corresponding to ) 2k An offset signal correction method calculated by adding ). Claim 4 In claim 1, the step of calculating the slope comprises the k-th minimum value of the Hall sensor signal value (k is a natural number) (m k The angle (θ) corresponding to ) 2k ) and the k-th maximum value of the above Hall sensor signal value (M k The angle (θ) corresponding to ) 2k-1 The above k-th maximum value (M) for the difference between ) k The first offset signal value (d) corresponding to ) 2k ) and the k-1th minimum value (m k-1 The first offset signal value (d) corresponding to ) 2k-1 The method includes a step of calculating the ratio of the difference between ) as the slope, wherein the second offset signal value is an angle (θ) corresponding to the k-th minimum value at the current angle (θ). 2k Subtract ) and the difference (θ) between the angle at which the maximum or minimum value occurs and the angle at which the Hall sensor signal value is updated. lag Multiplying the sum of ) by the above slope and the above k-th maximum value (M k The first offset signal value (d) corresponding to ) 2k An offset signal correction method calculated by adding ), where each angle value corresponds to the position value of the mover. Claim 5 delete Claim 6 An offset signal correction method according to claim 1, further comprising the step of calculating the position value of the mover based on the Hall sensor signal value and the second offset signal value. Claim 7 An offset signal correction method according to claim 1, wherein the second offset signal value is a linearly corrected first offset signal value. Claim 8 A computer program stored on a computer-readable recording medium in combination with hardware to execute the method of any one of claims 1, 3, 4, 6 and 7. Claim 9 An offset signal correction device for a Hall sensor, comprising: a Hall sensor signal value measuring unit for collecting a Hall sensor signal value from a Hall sensor of a stator for controlling the position of a mover of a moving magnet linear motor; and a calculation unit for correcting an offset signal value by calculating a first offset signal value based on the Hall sensor signal value and calculating a second offset signal value based on the first offset signal value and the Hall sensor signal value, wherein the calculation unit calculates the first offset signal value by calculating the average between the maximum value of the Hall sensor signal value and the minimum value of the Hall sensor signal value using a minimum-maximum algorithm, calculates the slope of the first offset signal value based on the first offset signal value, calculates the second offset signal value based on at least one of the calculated slope, the first offset signal value, a time value, and the position value of the mover, and corrects the offset signal value by replacing the first offset signal value with the second offset signal value. Claim 10 delete Claim 11 In claim 9, the calculation unit is the k-th minimum value of the Hall sensor signal value (k is a natural number) (m k The time value (t) corresponding to ) 2k ) and the k-th maximum value of the above Hall sensor signal value (M k The time value (t) corresponding to ) 2k-1 The above k-th maximum value (M) for the difference between ) k The first offset signal value (d) corresponding to ) 2k ) and the k-1th minimum value (m k-1 The first offset signal value (d) corresponding to ) 2k-1 The ratio of the difference between ) is calculated as the slope, and the second offset signal value is the time value (t) corresponding to the k-th minimum value at the current time value (t). 2k Subtract ) and the difference (T) between the time value at which the maximum or minimum value occurred and the time value at which the Hall sensor signal value is updated. lag Multiplying the sum of ) by the above slope and the above k-th maximum value (M k The first offset signal value (d) corresponding to ) 2k Offset signal correction device calculated by adding ). Claim 12 In claim 9, the calculation unit is the k-th minimum value of the Hall sensor signal value (k is a natural number) (m k The angle (θ) corresponding to ) 2k ) and the k-th maximum value of the above Hall sensor signal value (M k The angle (θ) corresponding to ) 2k-1 The above k-th maximum value (M) for the difference between ) k The first offset signal value (d) corresponding to ) 2k ) and the k-1th minimum value (m k-1 The first offset signal value (d) corresponding to ) 2k-1 The ratio of the difference between ) is calculated as the slope, and the second offset signal value is the angle (θ) corresponding to the k-th minimum value at the current angle (θ). 2k Subtract ) and the difference (θ) between the angle at which the maximum or minimum value occurs and the angle at which the Hall sensor signal value is updated. lag Multiplying the sum of ) by the above slope and the above k-th maximum value (M k The first offset signal value (d) corresponding to ) 2k An offset signal correction device calculated by adding ), where each angle value corresponds to the position value of the mover. Claim 13 delete Claim 14 In claim 9, the calculation unit is an offset signal correction device that calculates the position value of the mover based on the Hall sensor signal value and the second offset signal value. Claim 15 In claim 9, the offset signal correction device wherein the second offset signal value is a linearly corrected first offset signal value.

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