Method for thrust damping of an asynchronous linear propulsion motor device based on resistive damping injection

Abstract

The application discloses a thrust flattening method of an asynchronous linear propulsion motor device based on resistance damping injection, and belongs to the technical field of motors, which comprises the following steps: constructing an asynchronous linear propulsion motor device, wherein a pulse power supply system comprises pulse capacitors for supplying energy to each drive loop; a switching device comprises high-voltage switches for controlling the conduction of each loop; and a multi-stage drive coil comprises sub-coils which are arranged along a propulsion axis in a sequential and interval manner, each phase drive loop comprises at least two sub-coils, and the same phase winding is connected in series with opposite polarity. Based on the mutual inductance asymmetry characteristics caused by the longitudinal end effect, a phase with the maximum mutual inductance parameter is set as a reference phase, and the other two phases are set as compensation phases, a damping compensation resistor is connected in series in the loop, and the resistance value is configured so that the total resistance is greater than that of the reference phase, and the gradient increasing principle is followed. The damping resistor dissipates electric energy, suppresses the transient overshoot and oscillation of the compensation phase current, and reduces the thrust fluctuation.

Description

Technical Field

[0001] This invention belongs to the field of motor technology, specifically relating to a thrust mitigation method for an asynchronous linear propulsion motor device based on resistive damping injection. Background Technology

[0002] Asynchronous linear induction motors, due to their direct drive, fast response speed, and low mechanical friction loss, play an important role in applications requiring high motion stability, such as high-speed linear transport and electromagnetic propulsion. In these scenarios, the fluctuation amplitude of electromagnetic thrust, the consistency of the mover's acceleration, and the vibration and noise during system operation are often more critical than simple energy conversion efficiency.

[0003] However, the inherent longitudinal end effect of linear motors disrupts the symmetry of the three-phase magnetic circuit. From a circuit perspective, the reduction in the equivalent mutual inductance coefficient alters the equivalent inductance, natural frequency, and damping characteristics of that phase circuit, making it more prone to underdamped oscillations under pulse excitation. This characteristic can lead to significant transient overshoot and oscillations in the phase current. According to the principle of electromagnetic force generation, current spikes will be further amplified into larger thrust oscillations, thus affecting the system's operational stability.

[0004] Existing technologies mostly employ structural optimization or closed-loop feedback control. However, structural optimization is costly and lacks flexibility; feedback control is limited by bandwidth, making it difficult to respond to current surges during high-speed operation, and may even cause system resonance due to lag.

[0005] Furthermore, energy storage compensation schemes based on inductors or capacitors are prone to LC oscillations, making it difficult to effectively reduce spikes. Therefore, there is an urgent need for a suppression method with a simple structure and minimal response delay. Against this backdrop, developing a technology that utilizes a damping energy dissipation mechanism to sacrifice a small amount of energy for smooth electromagnetic thrust has significant engineering application value.

[0006] The technical problem to be solved by this invention is: to address the problem of current overshoot and electromagnetic thrust fluctuation caused by the difference in current response in different drive circuits of asynchronous linear propulsion motor devices, and to provide a circuit damping compensation method based on resistive energy consumption, and to provide a corresponding device or system. Summary of the Invention

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0008] A thrust mitigation method for an asynchronous linear propulsion motor device based on resistive damping injection includes: constructing an asynchronous linear propulsion motor device, including: multi-stage drive coils, a pulse power supply system, switching devices, and a mover;

[0009] The pulse power supply system includes pulse capacitors that supply power to each group of drive circuits;

[0010] The switching devices include high-voltage switches that control the conduction of each drive circuit respectively;

[0011] The mover is located within the axial channel formed by the multi-stage drive coils, and has no direct electrical connection with the multi-stage drive coils, but is coupled to each other through electromagnetic induction;

[0012] The multi-stage drive coil includes multiple sub-coils arranged sequentially at intervals along the propulsion axis. Each phase drive circuit includes at least two sub-coils. The sub-coils in the same phase drive circuit are connected in series with opposite polarities so that when adjacent sub-coils are energized, they generate magnetic fields with opposite polarities, forming an alternating polarity magnetic field distribution along the propulsion axis.

[0013] Based on the asymmetric mutual inductance caused by the longitudinal end effect, the three-phase drive circuit is divided into a reference phase circuit and a compensation phase circuit. The reference phase circuit is the phase where the mutual inductance parameter is at its maximum value, and the compensation phase circuit is the two-phase circuit where the mutual inductance parameter is reduced due to the end truncation effect. A damping compensation resistor is connected in series in the two compensation phase circuits, while no damping compensation resistor is connected in series in the reference phase circuit. The resistance value of the damping compensation resistor is configured such that the total resistance value of the compensation phase circuit is greater than the total resistance value of the reference phase circuit. In the two compensation phase circuits, the damping compensation resistor connected in series in the compensation phase circuit with the smaller mutual inductance parameter has a larger resistance value.

[0014] The present invention has the following beneficial effects:

[0015] (1) This invention achieves the dissipation of some electrical energy in the form of Joule heat and the reduction of current spikes by connecting differentiated high-energy damping compensation resistors in series in a specific phase drive circuit with small mutual inductance and obvious current overshoot; it solves the technical problems of current overshoot and electromagnetic thrust oscillation caused by longitudinal end effect.

[0016] (2) By using a low-inductance linear energy-consuming resistor as a compensation device, the present invention achieves damping adjustment without introducing additional energy storage components; it solves the technical problems of energy storage type (inductor / capacitor) compensation schemes being prone to secondary oscillations and difficult to effectively suppress current spikes.

[0017] (3) This invention achieves the technical effect of increasing the circuit damping ratio and suppressing underdamped oscillations by changing the resistance parameters of a specific circuit based on the damping control principle of second-order RLC circuit; it solves the technical problem of suppressing current oscillations without relying on complex feedback algorithms in high-speed transient operation. Attached Figure Description

[0018] Figure 1 A schematic diagram of the circuit topology of an asynchronous linear propulsion motor device;

[0019] Figure 2The figure shows a comparison of the simulation results of the three-phase current waveforms with and without resistance compensation.

[0020] Figure 3 A comparison of the simulation results of electromagnetic thrust waveforms before and after resistance compensation;

[0021] Figure 4 The figure shows the experimental results of the changes in the unbalance between the mover speed and the stator current before and after resistance compensation. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0023] This invention provides a thrust mitigation method for an asynchronous linear propulsion motor device based on resistive damping injection, comprising: constructing an asynchronous linear propulsion motor device, which includes: multi-stage drive coils, a pulse power supply system, switching devices, and a mover. The multi-stage drive coils are arranged sequentially along the axial direction. The pulse power supply system includes a first pulse capacitor C1, a second pulse capacitor C2, and a third pulse capacitor C3, which respectively supply power to each group of drive circuits.

[0024] The switching devices include a first high-voltage switch K1, a second high-voltage switch K2, and a third high-voltage switch K3, which respectively control the conduction of each drive circuit.

[0025] The mover is located within the axial channel formed by the multi-stage drive coils and has no direct electrical connection with the multi-stage drive coils. Instead, it is coupled to the multi-stage drive coils through electromagnetic induction.

[0026] The multiple sub-coils constituting the multi-stage drive coil are divided into phase A sub-coils, phase B sub-coils, and phase C sub-coils according to the drive circuit they are connected to. Each phase drive circuit includes at least two sub-coils arranged at intervals along the propulsion axis. Adjacent sub-coils in the same phase drive circuit are connected in series with opposite polarities, so that when adjacent sub-coils are energized, they generate magnetic fields in opposite directions, thereby forming an alternating polarity magnetic field distribution along the propulsion axis.

[0027] Based on the mutual inductance asymmetry caused by the longitudinal end effect, the three-phase drive circuit is divided into a reference phase circuit and a compensation phase circuit. The reference phase circuit is the phase where the mutual inductance parameter is at its maximum value, while the compensation phase circuit consists of two phase circuits where the mutual inductance parameter decreases due to end truncation. Damping compensation resistors are connected in series in both compensation phase circuits as differential resistance compensation modules. No damping compensation resistors are connected in series in the reference phase circuit, or its inherent internal resistance is maintained. The resistance value of the damping compensation resistors is configured such that the total resistance value of the compensation phase circuit is greater than that of the reference phase circuit, thereby increasing the damping ratio of the compensation phase circuit and suppressing current overshoot caused by mutual inductance asymmetry. In the two compensation phase circuits, the compensation phase circuit with the smaller mutual inductance parameter has a larger resistance value in series with the damping compensation resistor.

[0028] The three-phase drive circuit includes three winding circuits arranged sequentially in space: phase A, phase B, and phase C. Phase A is defined as the reference phase circuit, without a series damping compensation resistor or maintaining its inherent internal resistance. Phase B and phase C are defined as compensation phase circuits, with a phase B damping compensation resistor R connected in series, respectively. B_comp and C-phase damping compensation resistor R C_comp Among them, R B_comp and R C_comp The resistance value configuration follows the principle of gradient increase, satisfying the relationship: R C_comp >R B_comp。

[0029] Imbalance of three-phase current peak values This is the maximum absolute deviation between the first peak value of each of the three phase currents and the average value of the first peak values ​​of the three phases, divided by the average value of the first peak values ​​of the three phases, specifically:

[0030] ;

[0031] in, , and These are the first peak values ​​of the three-phase currents A, B, and C, respectively. This is the average value of the first peak value of the three-phase current; To find the maximum value function, This represents the maximum absolute deviation between the first peak value of each phase current and the average peak value of the three phases.

[0032] Adjust the resistance value of the damping compensation resistor according to the operating state of the mover to reduce the imbalance of the three-phase current peak value. The resistance value of the damping compensation resistor is determined using a proportional configuration method. First, a proportionality coefficient k is preset, with a range of 1 < k ≤ 2.5. The damping compensation resistor R of phase C is then set... C_comp The resistance value and the damping compensation resistor R of phase B B_comp The resistance value satisfies: RC_comp =k·R B_comp During the parameter scanning process, the proportional coefficient k remains constant, and the B-phase damping compensation resistor R... B_comp The resistance value is used as a scanning variable, and its resistance value is changed sequentially within a preset scanning range according to a preset step size. The C-phase damping compensation resistor R is determined synchronously according to the above proportional relationship. C_comp The resistance values ​​are selected to form multiple resistance value combinations. Under the same operating conditions, the peak three-phase current corresponding to each resistance value combination is obtained, and the imbalance of the three-phase current peak value is calculated. After testing all resistance value combinations within the preset scanning range, the resistance value combination with the smallest three-phase current peak imbalance is determined as the optimal resistance value combination.

[0033] The connection of the damping compensation resistor causes the amplitude of the current waveform in the compensation phase circuit to decrease, thereby making the envelope of the three-phase current more consistent. This reduces the system's kinetic energy conversion efficiency in exchange for the consistency of the mover exit velocity and the stability of the electromagnetic thrust.

[0034] The three-phase drive circuit includes: multi-stage drive coils and pulse power supply system;

[0035] The multi-stage drive coils are arranged sequentially along the axial direction and are divided into three sets of winding circuits: phase A, phase B, and phase C.

[0036] The pulse power supply system includes three independent capacitor energy storage modules, which are used to drive the A-phase, B-phase, and C-phase windings respectively.

[0037] The differential resistance compensation module includes at least two sets of damping compensation resistors, which are connected in series in the B-phase winding circuit and the C-phase winding circuit, respectively; the A-phase winding circuit is directly connected to the pulse power supply system and is not connected in series with damping compensation resistors.

[0038] The damping compensation resistor in the differential resistor compensation module is configured such that the damping compensation resistor of phase C is greater than that of phase B; the damping compensation resistor is configured as a low-inductance resistor capable of withstanding kilovolt-level pulse voltage and kiloampere-level pulse current.

[0039] This invention addresses a three-phase asynchronous linear motor system with insufficient mutual inductance and underdamped oscillating current response due to longitudinal end effects. By connecting a damping compensation resistor in series in the drive circuit of a specific phase, the energy dissipation characteristics of the resistor are utilized to increase the damping ratio of the circuit, attenuate the oscillation peaks of the current in each phase, thereby reducing the electromagnetic thrust pulsation caused by excess electromagnetic energy and achieving current amplitude balance and electromagnetic thrust stability.

[0040] Among them, the resistor-based damping injection achieves peak reduction and control of the three-phase current amplitude by adjusting the resistance value of the damping compensation resistor connected in series in the drive circuit of a specific phase of current overshoot, thereby optimizing the consistency of electromagnetic thrust of the high-speed moving mover.

[0041] The damping compensation resistor is configured asymmetrically based on the difference in mutual inductance of each phase coil due to the end effect. Usually, the resistor is connected in series in the phase with smaller mutual inductance and more obvious current overshoot (such as phase C and phase B), while the reference phase (such as phase A) does not have a resistor connected in series.

[0042] The resistance value of the damping compensation resistor is set according to the differentiated principle that the larger the overshoot, the larger the resistance value (e.g., The setting is based on the overshoot ratio of the three-phase current peak value when uncompensated, in order to reduce the amplitude asymmetry caused by the longitudinal end effect.

[0043] The damping characteristics of the drive circuit can be adjusted by changing the characteristic root distribution of the second-order RLC circuit by adjusting the value of the damping compensation resistor. The larger the value of the damping compensation resistor, the larger the circuit damping ratio, and the current waveform approaches the critical damping state from violent underdamped oscillation.

[0044] Damping compensation resistors utilize the Joule heat dissipation effect of resistive elements on high-amplitude currents. In the formula: P is the instantaneous power dissipation on the damping compensation resistor, I is the instantaneous value of the loop current flowing through the damping compensation resistor, and R is the resistance value of the damping compensation resistor. On the one hand, it directly flattens the peak of the overshoot current, and on the other hand, it suppresses the harmonic oscillation of the current.

[0045] Regarding energy conversion efficiency, this method adopts a lossy control strategy that sacrifices some of the system's kinetic energy to improve the smoothness of electromagnetic thrust. Specifically, by actively introducing a damping compensation resistor to dissipate excess electromagnetic energy, the method effectively suppresses electromagnetic thrust fluctuations while sacrificing some of the system's kinetic energy and reducing energy conversion efficiency in exchange for smoothness of electromagnetic thrust and mechanical stability during the movement process.

[0046] The damping compensation resistor energy consumption mechanism of the present invention provides an adjustable exchange mechanism for system stability and efficiency. The larger the damping resistor value, the lower the electromagnetic thrust ripple coefficient, but the greater the corresponding decrease in mover exit speed.

[0047] The thrust suppression method for asynchronous linear propulsion motors based on resistive damping injection of the present invention utilizes the damping characteristics and heat dissipation effect of resistors to reduce the difference in current amplitude between phases and suppress thrust oscillations through impedance matching of external passive devices without changing the motor body structure or relying on complex feedback control.

[0048] The principle of this invention:

[0049] Based on the equivalent lumped parameter circuit model analysis of the linear motor, its single-phase pulse discharge circuit can be electrically topologically equivalent to a typical second-order series RLC circuit. During motor operation, the longitudinal end effect caused by the primary core interruption weakens the magnetic coupling between windings, resulting in a significant decrease in the equivalent inductance parameter of the circuit. This abrupt change in inductance parameter directly alters the damping characteristics of the discharge circuit, causing it to deviate from the ideal state.

[0050] Based on the voltage balance relationship in the circuit, the dynamic mathematical model of the asynchronous linear propulsion motor device (voltage balance equation) is described as follows:

[0051] ;

[0052] in: This is the instantaneous voltage across the pulse capacitor. For the loop current of the damping compensation resistor. The time rate of change of the loop current. The equivalent inductance of the circuit (which is reduced due to end effect). The inherent resistance of the circuit. The resistance value is the damping compensation resistor connected in series in this invention.

[0053] During the discharge process of the pulse capacitor, taking the direction of the loop current flowing out from the positive terminal of the pulse capacitor as the positive direction, the terminal voltage of the pulse capacitor is... With loop current satisfy:

[0054] ;

[0055] To analyze the oscillation characteristics of the current, the voltage balance equation above is differentiated with respect to time, and the terminal voltage of the pulse capacitor is substituted into the equation. With loop current The above relationship yields a second-order homogeneous differential equation describing the dynamic behavior of current:

[0056] ;

[0057] in: This is the second derivative of the loop current with respect to time; is the capacitance of the pulse capacitor; other variables have the same meaning as in the above formula.

[0058] In this second-order homogeneous differential equation, the key parameter determining whether the current overshoots or oscillates is the damping ratio. Its defining formula is:

[0059] ;

[0060] It can be seen that: and Under constant conditions, damping ratio With the total resistance of the circuit ( It is directly proportional to .

[0061] Without compensation, due to end effect Decrease and When the damping is small, the system is often in an underdamped state. At this point, the current response will exhibit oscillating peaks.

[0062] This invention utilizes this characteristic to connect a damping compensation resistor with a resistance value in the milliohm to tens of milliohm range (e.g., 10mΩ to 100mΩ) in series for phases where current overshoot is significant. This will increase the damping ratio, causing the circuit state to move towards critical damping ( () or too damped. This increase in damping utilizes the Joule heat dissipation effect of the resistance:

[0063] ;

[0064] Where: P loss This represents the instantaneous power dissipation on the damping compensation resistor.

[0065] By physically dissipating the excess electromagnetic energy that causes oscillations, the peak amplitude of the current waveform is directly reduced. (i.e., the overshoot peak that appears in the current waveform under uncompensated conditions).

[0066] Furthermore, based on the principle of virtual displacement, the electromagnetic thrust of a linear motor... The loop current with the damping compensation resistor The square of the number is approximately proportional to the number of times it is scalar.

[0067] ;

[0068] in: Electromagnetic thrust, denoted as the rate of change of the loop inductance with respect to the axial displacement of the mover, i.e., the inductance gradient; x is the axial displacement of the mover along the linear propulsion direction.

[0069] Because electromagnetic thrust amplifies the current amplitude (square relationship), uncompensated current spikes can lead to significant thrust oscillations. This invention reduces thrust oscillations through resistive damping injection. This reduces thrust pulsation caused by current overshoot and smooths the electromagnetic thrust curve.

[0070] To meet the compensation accuracy requirements under different operating conditions and broaden the applicability of the solution, the damping compensation resistor includes the following optional technical details and alternative implementation schemes in terms of structural form and connection method:

[0071] (1) Alternative solutions for resistor structure: The damping compensation resistor adopts a low-inductance resistor, which includes a non-inductive wire-wound resistor or a metal foil resistor, to reduce the additional phase shift introduced by its own parasitic inductance under pulse.

[0072] (2) Alternative solutions for resistor connection position: The damping compensation resistor can be connected in series as a whole in the phase circuit between the output terminal of the pulse power supply and the first terminal of the multi-stage drive coil, or it can be split into multiple sub-resistors and connected in series between each stage of the multi-stage drive coil to achieve segmented distributed damping compensation along the propulsion axis.

[0073] (3) A replaceable solution with dynamically adjustable resistance: For the working condition where the acceleration of the mover changes drastically, a damping compensation structure with adjustable resistance in stages can be adopted, and the compensation resistance can be dynamically adjusted according to the system operating status, thereby suppressing the current peak and reducing the imbalance of the three-phase current peak.

[0074] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0075] like Figure 1 As shown, the asynchronous linear propulsion motor includes a first pulse capacitor C1, a second pulse capacitor C2, a third pulse capacitor C3, and a first high-voltage switch K1, a second high-voltage switch K2, and a third high-voltage switch K3 in the three-phase drive circuit, used to drive the mover to move along the v direction. To address the current overshoot problem caused by the longitudinal end effect, this scheme connects differentiated damping compensation resistors R in series in the B-phase and C-phase winding circuits with relatively small mutual inductance. B_comp and R C_comp Phase A remains directly connected as the reference phase circuit. This configuration creates a directional energy dissipation channel by physically increasing the resistance of a specific circuit to dissipate excess electromagnetic energy that could cause oscillations.

[0076] Figure 2 This is a comparison diagram of the three-phase current waveforms before and after resistance compensation, where I A I B I C For the original current, I A_comp I B_comp I C_comp This is the compensated current. Comparing the current waveforms, we can see that the original three-phase current I... A I B and I C The system exhibits transient overshoot, with a measured three-phase current imbalance as high as 11.9%. After introducing a damping compensation resistor (in this optimized configuration, R is taken as...),... B_comp =50.8mΩ, R C_comp =60.9mΩ), due to the increase in the loop damping ratio, the compensated current (I) B_comp and IC_comp It exhibits a significant peak-shaving effect, reducing the current imbalance to 1.9% (a reduction of approximately 84%). Unlike the phase shift caused by inductive compensation, resistive compensation mainly improves the balance of the three-phase current peaks by reducing the peak current of the compensated phase, making the current amplitude of each phase more consistent.

[0077] like Figure 3 As shown, by comparing the thrust characteristics, it can be seen that the uncompensated original electromagnetic thrust F Z The large fluctuations affect operational accuracy. The electromagnetic thrust F after resistance compensation... Z_comp The waveform became smoother, and the data showed that the electromagnetic thrust ripple coefficient decreased by about 7.4%, and the oscillation ripple was significantly reduced. Although the average electromagnetic thrust value decreased slightly due to energy dissipation, the consistency and linearity of the electromagnetic thrust curve were improved, reducing the possibility of causing mechanical resonance in the load.

[0078] like Figure 4 As shown, with the B-phase damping compensation resistor R B_comp and C-phase damping compensation resistor R C_comp As the resistance value increases, the three-phase current peak imbalance rate gradually decreases, indicating that the difference in current peak values ​​between phases A, B, and C gradually decreases, and the three-phase current amplitudes tend to be balanced. Simultaneously, the mover speed gradually decreases with increasing damping compensation resistor resistance. Figure 4 In the diagram, the horizontal axis represents the damping compensation resistance R of the B-phase and C-phase circuits. B R c The units are milliohms (mΩ), with the left ordinate representing the mover velocity (m / s) and the right ordinate representing the three-phase current peak imbalance rate. It can be seen that increasing the resistance values ​​of the B-phase and C-phase damping compensation resistors can improve the balance of the three-phase current peaks, but it will cause a decrease in the mover velocity. Therefore, the appropriate combination of damping compensation resistors can be selected based on the actual requirements of three-phase current balance and mover velocity.

[0079] The above description is merely an embodiment of the present invention and does not limit the scope of the invention. Any equivalent structural or procedural transformations made based on the description and drawings of this invention, or direct or indirect applications in other related system fields, are similarly included within the protection scope of this invention. Contents not described in detail in this specification are prior art known to those skilled in the art.

Claims

1. A thrust mitigation method for an asynchronous linear propulsion motor device based on resistive damping injection, characterized in that, include: Construct an asynchronous linear propulsion motor device, including: multi-stage drive coils, pulse power supply system, switching devices, and a mover; The pulse power supply system includes pulse capacitors that supply power to each group of drive circuits; The switching devices include high-voltage switches that control the conduction of each drive circuit respectively; The mover is located within the axial channel formed by the multi-stage drive coils, and has no direct electrical connection with the multi-stage drive coils, but is coupled to each other through electromagnetic induction; The multi-stage drive coil includes multiple sub-coils arranged sequentially at intervals along the propulsion axis. Each phase drive circuit includes at least two sub-coils. The sub-coils in the same phase drive circuit are connected in series with opposite polarities so that when adjacent sub-coils are energized, they generate magnetic fields with opposite polarities, forming an alternating polarity magnetic field distribution along the propulsion axis. Based on the asymmetric mutual inductance caused by the longitudinal end effect, the three-phase drive circuit is divided into a reference phase circuit and a compensation phase circuit. The reference phase circuit is the phase where the mutual inductance parameter is at its maximum value, and the compensation phase circuit is the two-phase circuit where the mutual inductance parameter is reduced due to the end truncation effect. A damping compensation resistor is connected in series in the two compensation phase circuits, while no damping compensation resistor is connected in series in the reference phase circuit. The resistance value of the damping compensation resistor is configured such that the total resistance value of the compensation phase circuit is greater than the total resistance value of the reference phase circuit. In the two compensation phase circuits, the damping compensation resistor connected in series in the compensation phase circuit with the smaller mutual inductance parameter has a larger resistance value.

2. The thrust mitigation method for an asynchronous linear propulsion motor device based on resistive damping injection according to claim 1, characterized in that, The three-phase drive circuit includes three winding circuits arranged sequentially in space: phase A, phase B, and phase C. Phase A is defined as the reference phase circuit, without a series damping compensation resistor or maintaining its inherent internal resistance. Phase B and phase C are defined as compensation phase circuits, with a phase B damping compensation resistor R connected in series, respectively. B_comp and C-phase damping compensation resistor R C_comp .

3. The thrust mitigation method for an asynchronous linear propulsion motor device based on resistive damping injection according to claim 2, characterized in that, Determining the resistance value of the damping compensation resistor includes: pre-setting the proportional coefficient k, k>1, and ensuring that the C-phase damping compensation resistor R... C_comp The resistance value and the damping compensation resistor R of phase B B_ comp The resistance value satisfies R C_comp =k·R B_comp The proportional relationship; while keeping the proportional coefficient k constant, changing R within the preset scanning range. B_comp The resistance value is determined, and R is simultaneously determined according to the aforementioned proportional relationship. C_comp The resistance values ​​are determined to form multiple resistance value combinations; the peak values ​​of the three-phase currents corresponding to each resistance value combination are obtained and the unbalance of the peak values ​​of the three-phase currents is calculated. The resistance value combination with the smallest unbalance of the peak values ​​of the three-phase currents is determined as the optimal resistance value combination.

4. The thrust mitigation method for an asynchronous linear propulsion motor device based on resistive damping injection according to claim 3, characterized in that, Imbalance of three-phase current peak values This is the maximum absolute deviation between the first peak value of each of the three phase currents and the average value of the first peak value of the three phases, divided by the average value of the first peak value of the three phases, and then multiplied by 100%.

5. The thrust mitigation method for an asynchronous linear propulsion motor device based on resistive damping injection according to claim 3, characterized in that, The range of values ​​for the proportionality coefficient k is: 1 < k ≤ 2.

5.

6. The thrust mitigation method for an asynchronous linear propulsion motor device based on resistive damping injection according to claim 1, characterized in that, The multiple sub-coils of the multi-stage drive coil are divided into phase A sub-coils, phase B sub-coils and phase C sub-coils according to the drive circuit they are connected to; the multiple sub-coils are respectively connected to phase A drive circuit, phase B drive circuit and phase C drive circuit, and each phase drive circuit includes at least two sub-coils; the sub-coils in the same phase drive circuit are connected in series with opposite polarities so that adjacent sub-coils in the same phase drive circuit generate magnetic fields with opposite directions when energized.

7. The thrust mitigation method for an asynchronous linear propulsion motor device based on resistive damping injection according to claim 1, characterized in that, The damping compensation resistor is a low-inductance resistor capable of withstanding kilovolt-level pulse voltages and kiloampere-level pulse currents.

8. The thrust mitigation method for an asynchronous linear propulsion motor device based on resistive damping injection according to claim 1, characterized in that, The damping compensation resistor is a non-inductive wire-wound resistor or a metal foil resistor.

9. The thrust mitigation method for an asynchronous linear propulsion motor device based on resistive damping injection according to claim 1, characterized in that, The damping compensation resistors are either centrally connected in series in the phase circuit between the output terminal of the pulse power supply and the first terminal of the multi-stage drive coil, or they are split into multiple sub-resistors and connected in series between each stage of the multi-stage drive coil to achieve segmented distributed damping compensation along the propulsion axis.

10. The thrust mitigation method for an asynchronous linear propulsion motor device based on resistive damping injection according to claim 1, characterized in that, The resistance value of the damping compensation resistor is adjustable; the resistance value of the damping compensation resistor is adjusted according to the operating state of the mover to reduce the imbalance of the three-phase current peak value.

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