Segmented linear induction motor thrust optimization control method based on stator reconstruction identification model

Abstract

The invention belongs to the technical field of motor control, particularly relates to a segmented linear induction motor thrust optimization control method based on a stator reconstruction identification model, and aims to solve the problem of thrust output reduction caused by parameter change of a segmented linear motor in short-time ultrahigh-speed operation. The method comprises the following steps: defining a stator length coefficient of an uncovered area of a rotor, and carrying out weighted average on segmented stator current to generate virtual stator current; a first-order low-pass filter is adopted to observe voltage of a non-coverage section, compensation reconstruction is carried out on voltage of a power supply section in combination with a length coefficient to obtain equivalent stator voltage, the equivalent stator voltage and virtual current are input into a reference model and an adjustable model respectively, and a rotor resistance identification value is generated through flux linkage errors of the equivalent stator voltage and the virtual current via a PI controller. And calculating the change rate of the identification value relative to the initial value, and synchronously adjusting the slip frequency given value to realize motor thrust optimization. According to the invention, the problem that the thrust output is reduced due to parameter change of the segmented linear motor in short-time ultrahigh-speed operation is effectively solved.

Description

Technical Field

[0001] This invention belongs to the field of motor control technology, and specifically relates to a thrust optimization control method and system for a piecewise linear induction motor based on a stator reconfiguration identification model. Background Technology

[0002] Segmented linear induction motors have the advantages of simple motion structure and good acceleration performance, making them suitable for ultra-high-speed electromagnetic propulsion of large-mass objects. Under high-current conditions, the mover induces a large number of eddy currents within seconds. The thermal effect of the metal material causes the secondary plate to heat up rapidly in a short time, and its resistance undergoes millisecond-level nonlinear changes. Under a constant slip frequency control method, the rapid change in mover resistance has a significant impact on maximizing the thrust output of the motor.

[0003] When segmented linear induction motors operate at high speeds, the parameters of the individual motors change rapidly with the movement of the secondary windings, greatly increasing the difficulty of identification. To improve the identification accuracy and performance of the secondary resistance and ensure stable thrust control, the paper "Online Parameter Identification of Linear Induction Motors Based on an Improved Interconnected Full-Order Observer," by Fu Rong and published in the *Journal of Southwest Jiaotong University*, proposes an interconnected full-order observer that improves the accuracy of identifying the excitation inductance and secondary resistance. However, this method does not consider the impact of parameter changes caused by primary segmentation and is not applicable to linear induction motors with long primary segments. The paper "Online Parameter Identification of Linear Induction Motors," by Ren Jinqi and published in the *Journal of Electrical Engineering*, proposes a method for identifying the excitation inductance of linear induction motors that only considers edge effects. However, this method does not consider the impact of rapid changes in the primary coverage ratio and switching, making it difficult to apply to the accurate identification of parameters in segmented linear induction motors.

[0004] Existing thrust control methods for linear induction motors employ steady-state control and do not consider the impact of highly dynamic changes in motor parameters under segmented structures on the motor's thrust output. This makes them difficult to apply to the dynamic thrust control of ultra-high-speed linear induction motors, and there is an urgent need for an effective parameter identification method for segmented linear induction motors.

[0005] Based on this, the present invention proposes a thrust optimization control method and system for a piecewise linear induction motor based on a stator reconfiguration identification model. Summary of the Invention

[0006] To address the aforementioned problems in the prior art, namely the decrease in thrust output caused by parameter changes during short-term ultra-high-speed operation of segmented linear motors, this invention provides a thrust optimization control method and system for segmented linear induction motors based on a stator reconfiguration identification model.

[0007] In a first aspect, the present invention proposes a thrust optimization control method for a piecewise linear induction motor based on a stator reconfiguration identification model, the method comprising:

[0008] Define the stator length coefficient for the uncovered area of ​​the mover; based on the stator length coefficient, perform a weighted average reconstruction of the segmented stator current to generate a virtual stator current;

[0009] The voltage of the uncovered stator segment is observed using a first-order low-pass filter. Based on the voltage of the uncovered stator segment and the stator length coefficient, the voltage of the power supply segment is compensated and reconstructed to obtain the reconstructed stator voltage.

[0010] The reconstructed equivalent stator voltage and virtual stator current are input into the reference model and the adjustable model. The flux linkage error between the reference model and the adjustable model is used to generate the mover resistance identification value through a proportional-integral controller. The reference model is constructed based on the flux linkage differential equation of the real mover resistance, and the adjustable model is constructed based on the flux linkage differential equation of the identified mover resistance.

[0011] Calculate the rate of change of the mover resistance identification value relative to the initial value, adjust the slip frequency setpoint synchronously based on the rate of change, and output the optimized motor thrust.

[0012] Furthermore, the stator length coefficient k for the uncovered region of the mover is defined. e The method is as follows:

[0013] k e = (1-α1)+(1-α2)+(1-α3);

[0014] Wherein, α1, α2 and α3 are the coverage ratio coefficients of the mover pair to the first stator segment, the second stator segment and the third stator segment, respectively.

[0015] Furthermore, based on the stator length coefficient, a weighted average is performed on the segmented stator currents to reconstruct a virtual stator current I. sv The method is as follows:

[0016]

[0017] Among them, I s1 I is the stator current of the first stator segment. s2 I is the stator current of the second stator segment. s3 This is the stator current of the third stator segment.

[0018] Furthermore, a first-order low-pass filter was used to observe the voltage u of the uncovered stator segment. e The method is as follows:

[0019]

[0020] Among them, L s For a single-segment inductor without a moving part covering the stator, i s R is the stator current. sIt is a single-segment stator resistor.

[0021] Furthermore, the voltage of the power supply section is compensated and reconstructed based on the voltage of the uncovered stator segment and the stator length coefficient to obtain the reconstructed stator voltage. The method is as follows:

[0022] The reconstructed stator voltage u is obtained by summing the voltages of each stator segment within the power supply section and subtracting the product of the voltage of the uncovered stator segment and the stator length coefficient of the uncovered portion. sv :

[0023]

[0024] Among them, u s1 The supply voltage for the first stator segment, u s2 The supply voltage for the second stator segment, u s3 The supply voltage for the third stator segment, u sv For the reconstructed stator voltage unaffected by changes in the mover position, u e For the uncovered stator segment voltage, i s1 Let i be the stator current of the first stator segment. s2 i is the stator current of the second stator segment. s3 R is the stator current of the third stator segment. s1 R is the resistance of the first stator segment. s2 R is the resistance of the second stator segment. s3 Let pψ be the resistance of the third stator segment. s1 For the differential of the flux linkage of the first stator segment, pψ s2 For the differential of the flux linkage of the second stator segment, pψ s3 The differential of the flux linkage of the third stator segment.

[0025] Furthermore, the reference model is constructed as follows:

[0026]

[0027] in, For the reconstructed voltage model, the mover flux linkage in the α-axis component, For the reconstructed voltage model mover flux linkage in the β-axis component, R sv For the reconstructed stator resistance, u svα For the α-axis component of the reconstructed stator voltage, u svβ For the β-axis component of the reconstructed stator voltage, I svα I is the α-axis component of the virtual stator current. svβ L is the β-axis component of the virtual stator current. sv For the reconstructed stator inductance, L mv Mutual inductance when the moving part is fully covered.

[0028] Furthermore, the adjustable model is constructed as follows:

[0029]

[0030] in, To reconstruct the current model, the mover flux linkage in the α-axis component, To reconstruct the current model, the mover flux linkage in the β-axis component, T r R is the mover time constant. rv For the reconstructed stator resistance, I svα I is the α-axis component of the virtual stator current. svβ Let d be the β-axis component of the virtual stator current, d be the differential operator, and t be the integration time.

[0031] Furthermore, the calculation method for the moving element resistance identification value is as follows:

[0032]

[0033] in, k p k is the proportional coefficient of the adaptive controller. i Here, R0 is the integral module coefficient of the adaptive controller, R0 is the mover resistance obtained from offline testing, k is a preset constant, and L is the integral module coefficient of the adaptive controller. lr For the leakage of the mover, T t Let Tt be the temperature of the mover at time t, T0 be the ambient temperature, and Δψ be the mover flux linkage residual estimated by the voltage model and the current model. The reconstructed mover flux linkage estimated by the voltage model. The actual mover flux linkage estimated by the current model in the α-axis component. The actual mover flux linkage estimated by the current model in the β-axis component.

[0034] Furthermore, the rate of change λ of the mover resistance identification value relative to the initial value is calculated as follows:

[0035]

[0036] Among them, R r This is the initial value.

[0037] Furthermore, the optimized motor thrust F e The calculation method is as follows:

[0038]

[0039] Among them, T e τ is the output thrust of the motor, τ is the pole pitch of the motor, and w f The given value for the motor's slip frequency, is Let λ be the stator current, λ be the rate of change, and a be the stator current. n L represents the stator-passive coverage ratio. m For mutual inductance between the stator and the mover, R r(T) The resistance value of the mover at temperature T.

[0040] In a second aspect, the present invention proposes a thrust optimization control system for a piecewise linear induction motor based on a stator reconfiguration identification model, and a thrust optimization control method for a piecewise linear induction motor based on a stator reconfiguration identification model. The system includes:

[0041] A virtual stator current generation module is configured to define a stator length coefficient for the uncovered area of ​​the mover; and to reconstruct a virtual stator current by weighted averaging the segmented stator currents based on the stator length coefficient.

[0042] The stator voltage reconfiguration module is configured to use a first-order low-pass filter to observe the voltage of the uncovered stator segment, and to reconstruct the voltage of the power supply segment based on the voltage of the uncovered stator segment and the stator length coefficient to obtain the reconstructed stator voltage.

[0043] The mover resistance identification value generation module is configured to input the reconstructed equivalent stator voltage and virtual stator current into a reference model and an adjustable model, and generate the mover resistance identification value through a proportional-integral controller based on the flux linkage error between the reference model and the adjustable model; wherein, the reference model is constructed based on the flux linkage differential equation of the real mover resistance, and the adjustable model is constructed based on the flux linkage differential equation of the identified mover resistance;

[0044] The motor thrust optimization module is configured to calculate the rate of change of the mover resistance identification value relative to the initial value, synchronously adjust the slip frequency setpoint based on the rate of change, and output the optimized motor thrust.

[0045] The beneficial effects of this invention are:

[0046] This invention effectively eliminates the interference of the primary segmented structure on the measurement signal by introducing a stator length coefficient for weighted average reconstruction of the current and employing voltage compensation reconstruction technology, thus constructing a more accurate equivalent electrical model. By utilizing the flux linkage error generated from comparing the reference model and the adjustable model, combined with a proportional-integral controller, real-time online identification of the mover resistance, which changes nonlinearly at the millisecond level under high-speed operation, is achieved. This method directly targets the change in the key parameter resistance, offering high identification accuracy and fast dynamic response.

[0047] By calculating the rate of change of the mover resistance identification value relative to the initial value in real time, and dynamically adjusting the slip frequency setpoint accordingly, the impact of resistance changes caused by temperature rise on thrust can be compensated in real time. This overcomes the problem of thrust output reduction and fluctuation caused by rapid time-varying parameters under high-speed and high-current conditions in traditional steady-state control methods, and achieves maximum and high stability of motor thrust output during ultra-high-speed operation.

[0048] This invention is specifically designed for the structural characteristics of segmented linear induction motors, fully considering the impact of key factors such as primary segmentation, rapid changes in coverage ratio, switching, and edge effects on parameter identification and control. It solves the problem of insufficient adaptability of existing identification methods in segmented structures, providing an effective online parameter identification and thrust control solution for linear induction motors with long primary segments. Attached Figure Description

[0049] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0050] Figure 1 This is a control block diagram of the segmented linear induction motor thrust optimization control method based on the stator reconfiguration identification model of the present invention;

[0051] Figure 2 Equivalent circuit diagram for a segmented power supply linear induction motor;

[0052] Figure 3 Comparison of reconstructed voltage and current waveforms for a segmented linear induction motor; where (a) is a schematic diagram showing the actual stator α-axis voltage and β-axis voltage fluctuating with the mover without reconstruction; (b) is a schematic diagram showing the actual stator α-axis voltage and β-axis voltage without fluctuating with the mover after reconstruction; (c) is a schematic diagram showing the overshoot of the actual stator α-axis current and β-axis current without reconstruction; and (d) is a schematic diagram showing the actual stator α-axis current and β-axis current without overshoot after reconstruction.

[0053] Figure 4 The results are based on the mover resistance identification of a single-segment motor.

[0054] Figure 5 The results show the moving element resistance identification based on voltage-current reconstruction.

[0055] Figure 6 To compare the motor thrust obtained based on the reconstructed stator identification model with traditional results;

[0056] Figure 7 The results show the comparison of motor acceleration processes under the variable slip frequency control method. Detailed Implementation

[0057] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0058] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0059] The first embodiment of the present invention provides a thrust optimization control method for a piecewise linear induction motor based on a stator reconfiguration identification model, the method comprising:

[0060] Step S10: Define the stator length coefficient for the uncovered area of ​​the mover; reconstruct the virtual stator current by weighted averaging the segmented stator current based on the stator length coefficient;

[0061] Step S20: Observe the voltage of the uncovered stator segment using a first-order low-pass filter, and reconstruct the voltage of the power supply segment based on the voltage of the uncovered stator segment and the stator length coefficient to obtain the reconstructed stator voltage.

[0062] Step S30: The reconstructed equivalent stator voltage and virtual stator current are input into the reference model and the adjustable model. The motor resistance identification value is generated by the proportional-integral controller through the flux linkage error between the reference model and the adjustable model. The reference model is constructed based on the flux linkage differential equation of the real motor resistance, and the adjustable model is constructed based on the flux linkage differential equation of the identified motor resistance.

[0063] Step S40: Calculate the rate of change of the mover resistance identification value relative to the initial value, adjust the slip frequency setpoint synchronously based on the rate of change, and output the optimized motor thrust.

[0064] To more clearly explain the thrust optimization control method for a piecewise linear induction motor based on a stator reconfiguration identification model of the present invention, the following will be combined with... Figure 1 The steps in the embodiments of the present invention are described in detail below:

[0065] Step S10: Define the stator length coefficient for the uncovered area of ​​the mover; reconstruct the virtual stator current by weighted averaging the segmented stator current based on the stator length coefficient;

[0066] First, a stator voltage and current reconstruction model of the segmented linear induction motor is established to obtain the voltage and current independent of the motor segmentation and mover position. The voltage equation of the linear induction motor in the two-phase stationary coordinates in step 1 is shown in equation (1):

[0067]

[0068] Among them, u αs u represents the component of the stator voltage along the α-axis. βs i represents the component of the stator voltage along the β axis. αs Let i be the component of the stator current along the α-axis. βs i represents the component of the stator current along the β axis. αr Let i be the component of the mover current along the α-axis. βr R represents the component of the mover current along the β axis. s R is the stator resistance. r For the resistance of the moving part; ψ αs Let ψ be the component of the stator flux linkage along the α-axis. βs Let ψ be the component of the stator flux linkage along the β axis. αr Let ψ be the component of the mover flux linkage along the α-axis. βr ω represents the component of the mover flux linkage along the β axis. re a is the electric angular velocity of the mover; n is the proportionality coefficient of the stator covering the mover long unit, and p is the differential operator.

[0069] The flux linkage equation is shown in equation (2):

[0070]

[0071] Among them, L ls and L lr For the leakage inductance of the motor stator and rotor, L m Mutual inductance when the moving part is fully covered.

[0072] First, define the stator length coefficient k for the uncovered portion of the power supply section's mover. e As shown in equation (3):

[0073] k e =(1-α1)+(1-α2)+(1-α3) (3)

[0074] Wherein, α1, α2 and α3 are the coverage ratio coefficients of the mover pair to the first stator segment, the second stator segment and the third stator segment, respectively.

[0075] In this embodiment, to avoid the impact of overshoot of the single-segment motor stator current at the switching point on the virtual stator current, the virtual stator current is reconstructed using a weighted average method. Specifically, the segmented stator currents are reconstructed by weighted averaging based on the stator length coefficient to generate the virtual stator current I. sv The method is shown in equation (4):

[0076]

[0077] Among them, I s1I is the stator current of the first stator segment. s2 I is the stator current of the second stator segment. s3 This is the stator current of the third stator segment.

[0078] Step S20: Observe the voltage of the uncovered stator segment using a first-order low-pass filter, and reconstruct the voltage of the power supply segment based on the voltage of the uncovered stator segment and the stator length coefficient to obtain the reconstructed stator voltage.

[0079] In this embodiment, after obtaining the virtual stator current, the virtual stator segment voltage under the mover coverage needs to be obtained. First, the terminal voltage of the stator segment S1-an1 of the motor without mover coverage needs to be calculated. A first-order low-pass filter is used to observe the voltage of a single motor segment without mover coverage. Since the motor is supplied with AC current from the frequency converter, the real-time observation equation for the dynamic voltage change is as shown in equation (5):

[0080]

[0081] Among them, L s For a single-segment inductor without a moving part covering the stator, i s R is the stator current. s It is a single-segment stator resistor.

[0082] In this embodiment, the power supply segment voltage is compensated and reconstructed based on the uncovered stator segment voltage and the stator length coefficient to obtain the reconstructed stator voltage. The method is as follows:

[0083] The reconstructed stator voltage u is obtained by summing the voltages of each stator segment within the power supply section and subtracting the product of the voltage of the uncovered stator segment and the stator length coefficient of the uncovered portion. sv As shown in equation (6):

[0084]

[0085] Among them, u s1 The supply voltage for the first stator segment, u s2 The supply voltage for the second stator segment, u s3 The supply voltage for the third stator segment, u sv For the reconstructed stator voltage unaffected by changes in the mover position, u e For the uncovered stator segment voltage, i s1 Let i be the stator current of the first stator segment. s2 i is the stator current of the second stator segment. s3 R is the stator current of the third stator segment. s1 R is the resistance of the first stator segment. s2 R is the resistance of the second stator segment. s3 Let pψ be the resistance of the third stator segment.s1 For the differential of the flux linkage of the first stator segment, pψ s2 For the differential of the flux linkage of the second stator segment, pψ s3 The differential of the flux linkage of the third stator segment.

[0086] Step S30: The reconstructed equivalent stator voltage and virtual stator current are input into the reference model and the adjustable model. The motor resistance identification value is generated by the proportional-integral controller through the flux linkage error between the reference model and the adjustable model. The reference model is constructed based on the flux linkage differential equation of the real motor resistance, and the adjustable model is constructed based on the flux linkage differential equation of the identified motor resistance.

[0087] In this embodiment, after obtaining the voltage and current that do not change with the position of the mover, the identification model after the segmented motor voltage and current reconstruction can be designed by combining the adaptive identification algorithm. The reference model and adjustable model of adaptive identification are re-derived as shown in equations (7) and (8):

[0088]

[0089] in, For the reconstructed voltage model, the mover flux linkage in the α-axis component, For the reconstructed voltage model mover flux linkage in the β-axis component, R sv For the reconstructed stator resistance, u svα For the α-axis component of the reconstructed stator voltage, u svβ For the β-axis component of the reconstructed stator voltage, I svα I is the α-axis component of the virtual stator current. svβ L is the β-axis component of the virtual stator current. sv For the reconstructed stator inductance, L mv Mutual inductance when the moving part is fully covered.

[0090] In this embodiment, the adjustable model is constructed as follows:

[0091]

[0092] in, To reconstruct the current model, the mover flux linkage in the α-axis component, To reconstruct the current model, the mover flux linkage in the β-axis component, T r R is the mover time constant. rv For the reconstructed stator resistance, I svα I is the α-axis component of the virtual stator current. svβ Let d be the β-axis component of the virtual stator current, d be the differential operator, and t be the integration time.

[0093] In this embodiment, based on the established adaptive identification model, an adaptive rate can be designed to identify the mover resistance identification result with high robustness to dynamic processes. The relevant adaptive rate and the mover resistance identification value are calculated as shown in equation (9):

[0094]

[0095] in, k p k is the proportional coefficient of the adaptive controller. i R0 is the integral module coefficient of the adaptive controller, R0 is the mover resistance obtained from offline testing, k is a preset constant, and according to the testing method, k is generally taken as 225, L lr For the leakage of the mover, T t Let Tt be the temperature of the mover at time t, T0 be the ambient temperature, and Δψ be the mover flux linkage residual estimated by the voltage model and the current model. The reconstructed mover flux linkage estimated by the voltage model. The actual mover flux estimated by the current model in the α-axis component... The actual mover flux linkage estimated by the current model in the β-axis component.

[0096] Step S40: Calculate the rate of change of the mover resistance identification value relative to the initial value, adjust the slip frequency setpoint synchronously based on the rate of change, and output the optimized motor thrust.

[0097] Based on the dynamic identification of the mover resistance, the motor slip frequency can be adjusted in real time to keep the motor output thrust at the maximum thrust output point. The thrust formula of the linear induction motor can be obtained from the thrust of the linear induction motor, as shown in equation (10):

[0098]

[0099] In this embodiment, the rate of change λ of the mover resistance identification value relative to the initial value is calculated as shown in equation (11):

[0100]

[0101] Among them, R r This is the initial value.

[0102] In this embodiment, the motor slip frequency is given in the same way as the rate of change of the mover resistance. By rewriting equation (10), the optimized thrust formula of the motor can be obtained, as shown in equation (11). The optimized motor thrust F e The calculation method is as follows:

[0103]

[0104] Among them, T e τ is the output thrust of the motor, τ is the pole pitch of the motor, and w f Given a value for the motor's slip frequency, a n L represents the stator-passive coverage ratio. m For mutual inductance between the stator and the mover, R r(T) The resistance value of the mover at temperature T.

[0105] Figure 2 The equivalent circuit diagram of the segmented linear induction motor is shown below. Un, Un+1, and Un+2 represent three voltage sources, and Sn, Sn+1, and Sn+2 represent the primary segment of the segmented linear induction motor. When the secondary high-speed passes through the primary segment, the parameters of the linear induction motor exhibit discontinuous and rapidly changing time-varying characteristics with an.

[0106] Figure 3 The diagram shows the voltage and current waveforms before and after reconstruction. By comparing (a), (c) and (b), (d), it can be seen that the voltage and current waveforms of the motor after reconstruction are stable and unaffected by the segmented structure of the motor, and can be used as input for the adaptive identification model after reconstruction.

[0107] Figure 4 and Figure 5 A comparison of the mover resistance identification results for segmented linear induction motors shows that... Figure 4 The resistance identification results can stably track parameter changes in the motor mover caused by temperature variations, compared to... Figure 5 It can be seen that, Figure 5 In the traditional single-segment linear induction motor identification process, the identification results fluctuate rapidly with the position of the mover, and the identification values ​​deviate significantly from the actual values ​​at the moment of power supply switching between segments. However, the reconstructed identification model can accurately characterize the dynamic change process of motor parameters.

[0108] Figure 6 The waveform diagram shows the thrust optimization of a piecewise linear induction motor based on a stator reconfiguration identification model. Before 0.75 seconds, a constant slip frequency control method is used. It can be seen that as the motor operates at high speed and high current, changes in the motor's mover parameters make it difficult for the motor to output maximum thrust. Furthermore, the motor's thrust gradually decreases as the motor continues to run. At 0.75 seconds, the control method switches to a variable slip frequency method. Compared to the traditional constant slip frequency control method, the motor's output thrust is increased by 22.6%.

[0109] Figure 7The waveform diagram shows the motor speed. After optimizing the thrust of the segmented linear induction motor based on the stator reconfiguration identification model, the motor output thrust significantly improves the acceleration process under the same acceleration time setting. Compared with the constant slip frequency control method, the acceleration time of the motor is shortened by 0.187 seconds, which is 13%.

[0110] Although the steps in the above embodiments are described in the above order, those skilled in the art will understand that in order to achieve the effect of this embodiment, different steps do not need to be executed in such an order. They can be executed simultaneously (in parallel) or in a reverse order. These simple variations are all within the protection scope of this invention.

[0111] A second embodiment of the present invention provides a segmented linear induction motor thrust optimization control system based on a stator reconfiguration identification model, and a segmented linear induction motor thrust optimization control method based on a stator reconfiguration identification model. The system includes:

[0112] A virtual stator current generation module is configured to define a stator length coefficient for the uncovered area of ​​the mover; and to reconstruct a virtual stator current by weighted averaging the segmented stator currents based on the stator length coefficient.

[0113] The stator voltage reconfiguration module is configured to use a first-order low-pass filter to observe the voltage of the uncovered stator segment, and to reconstruct the voltage of the power supply segment based on the voltage of the uncovered stator segment and the stator length coefficient to obtain the reconstructed stator voltage.

[0114] The mover resistance identification value generation module is configured to input the reconstructed equivalent stator voltage and virtual stator current into a reference model and an adjustable model, and generate the mover resistance identification value through a proportional-integral controller based on the flux linkage error between the reference model and the adjustable model; wherein, the reference model is constructed based on the flux linkage differential equation of the real mover resistance, and the adjustable model is constructed based on the flux linkage differential equation of the identified mover resistance;

[0115] The motor thrust optimization module is configured to calculate the rate of change of the mover resistance identification value relative to the initial value, synchronously adjust the slip frequency setpoint based on the rate of change, and output the optimized motor thrust.

[0116] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working process and related descriptions of the system described above can be found in the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0117] It should be noted that the segmented linear induction motor thrust optimization control system based on a stator reconfiguration identification model provided in the above embodiments is only an example of the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the modules or steps in the embodiments of the present invention can be further decomposed or combined. For example, the modules in the above embodiments can be merged into one module, or further divided into multiple sub-modules to complete all or part of the functions described above. The names of the modules and steps involved in the embodiments of the present invention are only for distinguishing the various modules or steps and are not considered as an improper limitation of the present invention.

[0118] An electronic device according to a third embodiment of the present invention includes:

[0119] At least one processor; and

[0120] A memory communicatively connected to at least one of the processors; wherein,

[0121] The memory stores instructions that can be executed by the processor to implement the above-described method for optimizing thrust control of a segmented linear induction motor based on a stator reconfiguration identification model.

[0122] A fourth embodiment of the present invention provides a computer-readable storage medium storing computer instructions, which are executed by the computer to implement the above-described method for thrust optimization control of a segmented linear induction motor based on a stator reconfiguration identification model.

[0123] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working process and related descriptions of the storage device and processing device described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0124] Those skilled in the art will recognize that the modules and method steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. The programs corresponding to the software modules and method steps can be placed in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disks, removable disks, CD-ROMs, or any other form of storage medium known in the art. To clearly illustrate the interchangeability of electronic hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in electronic hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the invention.

[0125] The terms “first”, “second”, etc., are used to distinguish similar objects, not to describe or indicate a specific order or sequence.

[0126] The term "comprising" or any other similar term is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus / device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent in such process, method, article, or apparatus / device.

[0127] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles 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 all fall within the scope of protection of the present invention.

Claims

1. A thrust optimization control method for a piecewise linear induction motor based on a stator reconfiguration identification model, characterized in that, The method includes: Define the stator length coefficient for the uncovered area of ​​the mover; based on the stator length coefficient, perform a weighted average reconstruction of the segmented stator current to generate a virtual stator current; The voltage of the uncovered stator segment is observed using a first-order low-pass filter. Based on the voltage of the uncovered stator segment and the stator length coefficient, the voltage of the power supply segment is compensated and reconstructed to obtain the reconstructed stator voltage. The reconstructed equivalent stator voltage and virtual stator current are input into the reference model and the adjustable model. The flux linkage error between the reference model and the adjustable model is used to generate the mover resistance identification value through a proportional-integral controller. The reference model is constructed based on the flux linkage differential equation of the real mover resistance, and the adjustable model is constructed based on the flux linkage differential equation of the identified mover resistance. Calculate the rate of change of the mover resistance identification value relative to the initial value, adjust the slip frequency setpoint synchronously based on the rate of change, and output the optimized motor thrust.

2. The method for optimizing thrust control of a piecewise linear induction motor based on a stator reconfiguration identification model according to claim 1, characterized in that, Define the stator length coefficient k for the uncovered region of the mover. e The method is as follows: k e ＝(1-α1)+(1-α2)+(1-α3)； Wherein, α1, α2 and α3 are the coverage ratio coefficients of the mover pair to the first stator segment, the second stator segment and the third stator segment, respectively.

3. The method for optimizing thrust control of a piecewise linear induction motor based on a stator reconfiguration identification model according to claim 2, characterized in that, Based on the stator length coefficient, a weighted average of the segmented stator currents is reconstructed to generate a virtual stator current I. sv The method is as follows: Among them, I s1 I is the stator current of the first stator segment. s2 I is the stator current of the second stator segment. s3 This is the stator current of the third stator segment.

4. The method for optimizing thrust control of a piecewise linear induction motor based on a stator reconfiguration identification model according to claim 1, characterized in that, The voltage u of the uncovered stator segment was observed using a first-order low-pass filter. e The method is as follows: Among them, L s The inductance is a single segment of the stator without a moving part, is the stator current, and R is the inductance. s It is a single-segment stator resistor.

5. The method for optimizing thrust control of a piecewise linear induction motor based on a stator reconfiguration identification model according to claim 1, characterized in that, The power supply section voltage is compensated and reconstructed based on the uncovered stator segment voltage and the stator length coefficient to obtain the reconstructed stator voltage. The method is as follows: The reconstructed stator voltage u is obtained by adding the voltages of each stator segment within the power supply section and subtracting the product of the voltage of the uncovered stator segment and the stator length coefficient of the uncovered portion. sv : Among them, u s1 The supply voltage for the first stator segment, u s2 The supply voltage for the second stator segment, u s3 The supply voltage for the third stator segment, u sv For the reconstructed stator voltage unaffected by changes in the mover position, u e For the uncovered stator segment voltage, i s1 Let i be the stator current of the first stator segment. s2 i is the stator current of the second stator segment. s3 R is the stator current of the third stator segment. s1 R is the resistance of the first stator segment. s2 R is the resistance of the second stator segment. s3 For the resistance of the third stator segment, pψ s1 For the differential of the flux linkage of the first stator segment, pψ s2 For the differential of the flux linkage of the second stator segment, pψ s3 The differential of the flux linkage of the third stator segment.

6. The thrust optimization control method for a piecewise linear induction motor based on a stator reconfiguration identification model according to claim 1, characterized in that, The reference model is constructed as follows: in, For the reconstructed voltage model, the mover flux linkage in the α-axis component, For the reconstructed voltage model mover flux linkage in the β-axis component, R sv For the reconstructed stator resistance, u svα For the α-axis component of the reconstructed stator voltage, u svβ For the β-axis component of the reconstructed stator voltage, I svα I is the α-axis component of the virtual stator current. svβ L is the β-axis component of the virtual stator current. sv For the reconstructed stator inductance, L mv Mutual inductance when the moving part is fully covered.

7. The method for optimizing thrust control of a piecewise linear induction motor based on a stator reconfiguration identification model according to claim 1, characterized in that, The adjustable model is constructed as follows: in, To reconstruct the current model, the mover flux linkage in the α-axis component, To reconstruct the current model, the mover flux linkage in the β-axis component, T r R is the mover time constant. rv For the reconstructed stator resistance, I svα I is the α-axis component of the virtual stator current. svβ Let d be the β-axis component of the virtual stator current, d be the differential operator, and t be the integration time.

8. The method for optimizing thrust control of a piecewise linear induction motor based on a stator reconfiguration identification model according to claim 1, characterized in that, The moving element resistance identification value The calculation method is as follows: in, k p k is the proportional coefficient of the adaptive controller. i R0 is the integral module coefficient of the adaptive controller, R0 is the mover resistance obtained from offline testing, and L0 is the integral module coefficient of the adaptive controller. mv Let L be the mutual inductance when the moving part is fully covered, k be a preset constant, and L be the mutual inductance. lr For the leakage of the mover, T t Let Tt be the temperature of the mover at time t, T0 be the ambient temperature, and Δψ be the mover flux linkage residual estimated by the voltage model and the current model. The reconstructed mover flux linkage estimated by the voltage model. The actual mover flux linkage estimated by the current model in the α-axis component. The actual mover flux linkage estimated by the current model in the β-axis component.

9. The thrust optimization control method for a piecewise linear induction motor based on a stator reconfiguration identification model according to claim 1, characterized in that, The rate of change λ of the identified value of the mover resistance relative to the initial value is calculated as follows: Among them, R r This is the initial value.

10. The method for optimizing thrust control of a piecewise linear induction motor based on a stator reconfiguration identification model according to claim 1, characterized in that, Optimized motor thrust F e The calculation method is as follows: Among them, T e τ is the output thrust of the motor, τ is the pole pitch of the motor, and w f The given value is the slip frequency of the motor, is is the stator current, λ is the rate of change, and a is the value of the slip frequency. n L represents the stator-passive coverage ratio. m For mutual inductance between the stator and the mover, R r(T) The resistance value of the mover at temperature T.

Images