An adaptive control method for a submerged linear motor control cabinet

Abstract

The application discloses a kind of submersible linear motor control cabinet adaptive control method, it is related to oil exploitation field, and the method comprises: in first calibration, three-phase alternating voltage is driven by control cabinet output, and in turn downlink and uplink of mover, respectively detect upper and lower end collision position to determine mechanical stroke, and in each reduction free collision interval in upper and lower end point, obtain effective running stroke, and mover is reciprocated according to set parameter in effective stroke;Control cabinet sets initial stroke, stroke adjustment interval and step, and carries out adaptive adjustment in combination with evacuation monitoring module: when not detecting evacuation in certain interval, stroke increases;When detecting evacuation, stroke decreases, to dynamically match working condition;Evacuation monitoring is realized by comparing with threshold value by counting the number of times of upper end collision of mover, and when the number of times of upper end collision reaches threshold value, evacuation is determined;The application can realize the automatic calibration of linear motor running stroke and the adaptive adjustment of stroke, improve oil pumping efficiency and the safety and reliability of equipment operation.

Description

Technical Field

[0001] This invention relates to the technical field of oil extraction, and more specifically, to an adaptive control method for a submersible linear motor control cabinet. Background Technology

[0002] With the increasing number of lean oil wells, submersible electric deep-sea pumps based on submersible linear motors are being used more and more widely, leading to a corresponding increase in the types of linear motors. Different linear motors have different strokes, and to achieve stroke matching, currently, dedicated linear motor control cabinets are often developed for different linear motors. This results in too many models of linear motor control cabinets, making maintenance and use inconvenient.

[0003] For oil wells using linear motor deep-pump pumps, the well fluid level is constantly changing due to factors such as crude oil reserves, water injection volume, and seasonal groundwater level fluctuations. To fully utilize the well's production capacity, the stroke rate of the dynamic submersible linear motor is required. Currently, oilfields periodically (usually quarterly) measure fluid level data, and frontline operators manually adjust the linear motor stroke rate based on the measurement results. This leads to a lag in stroke rate adjustment, which is detrimental to fully utilizing the well's production capacity, and also increases the oilfield's operating costs and workload. Summary of the Invention

[0004] The purpose of this invention is to provide an adaptive control method for a submersible linear motor control cabinet, which realizes automatic calibration of mechanical stroke and adaptive adjustment of stroke rate to avoid rotor collision and cavitation, thereby ensuring equipment safety and improving oil well productivity utilization.

[0005] The technical solution of this invention is: to provide an adaptive control method for a submersible linear motor control cabinet, the method comprising:

[0006] Before the first calibration, the control cabinet of the submersible linear motor is placed in the calibration state according to the preset parameters, and the collision monitoring module, displacement detection module, drive output module and recording and storage module are powered on and put into the working preparation state.

[0007] The control cabinet outputs a preset three-phase AC voltage to the motor, causing the mover to slowly move downward from a random initial position. At the same time, the collision monitoring module detects collision events between the mover and the stator in real time. When a collision is detected at the lower end, the output voltage is stopped and the stopping position is defined as the mechanical travel zero point of the linear motor in the control program. The mover is held at the zero point for several seconds to complete the initial positioning and steady-state signal acquisition.

[0008] The phase sequence of the three-phase voltage is changed to make the mover move upward. When moving upward, the displacement detection module and the collision monitoring module work synchronously to record the displacement information and collision events of the mover relative to the zero point in real time. When the upper collision is detected, the output voltage is stopped and the upper collision position is recorded as the upper end point of the mechanical stroke. The mechanical stroke S0 of the linear motor is calculated based on the displacement and drive frequency data recorded by the control cabinet.

[0009] The upper and lower endpoints of the mechanical stroke are both reduced inward by the preset collision-free interval h. The reduced upper and lower endpoints are used as the formal upper and lower endpoints of the running stroke. The total effective running stroke is S0-2h, so that the mover can reciprocate stably between the formal upper and lower endpoints according to the set drive parameters.

[0010] The control cabinet performs adaptive stroke adjustment according to the set stroke adaptive control process: setting the initial stroke m, the cavitation monitoring module, the stroke adjustment interval T0, and the stroke adjustment step size a; within each stroke adjustment interval T0, the stroke m is adjusted by increasing or decreasing according to the cavitation monitoring results; when no cavitation event is detected during T0, m increases to m+a; when a cavitation event is detected during T0, m decreases to ma; and the operation continues with a new stroke and the above cycle is repeated.

[0011] In any of the above technical solutions, the evacuation monitoring module is further implemented by an evacuation monitoring algorithm, which includes:

[0012] The cavitation monitoring program establishes a cavitation counter and initializes it to 0. In each running loop, if a collision is detected on the upper end of the mover, the cavitation counter is incremented by 1. The monitoring program counts the number of collisions within a given statistical window or a certain number of repetitions and compares it with the threshold N0. When the number of collisions within the statistical window is greater than or equal to the threshold N0, it is determined that cavitation has occurred and the cavitation counter is cleared. Otherwise, it continues to accumulate or the counter is reset according to the set rules outside the window.

[0013] In any of the above technical solutions, the formula for calculating the mechanical stroke S0 of the linear motor is further as follows:

[0014]

[0015] In the formula, S0 is the mechanical stroke of the linear motor, n is the total number of switching cycles, and v k The linear motor's operating speed corresponding to each switching cycle; because the linear motor is a permanent magnet synchronous motor, its speed v k =2τf k In the formula f k Let τ be the three-phase voltage frequency of the drive motor during each switching cycle, τ be the motor pole pitch, and t be a mechanical constant; sThe switching cycle of the linear motor control cabinet using PWM control ranges from several microseconds to tens of microseconds; the motor pole pitch τ and the switching cycle t s Both are constants, while the three-phase voltage frequency f corresponding to each switching cycle is... k The preset value of the control program is known to the control program.

[0016] In any of the above technical solutions, further, when the control cabinet changes the phase sequence of the three-phase voltage from decreasing to increasing, the frequency and effective value remain unchanged.

[0017] In any of the above technical solutions, while implementing evacuation monitoring and stroke adaptive control, the control cabinet maintains real-time acquisition and storage of key operating parameters such as collision events, displacement curves, drive frequency, power and current; when multiple abnormal collisions or abnormal drive current are detected, the fault protection logic is triggered and the system enters a safe shutdown or alarm mode according to a preset program, while the event is recorded for subsequent fault diagnosis and correction.

[0018] The beneficial effects of this invention are:

[0019] The technical solution of this invention realizes online automatic calibration of mechanical stroke. By detecting collisions between the lower and upper ends, the actual mechanical stroke of the linear motor is automatically determined and dynamically corrected, avoiding reliance on manual calibration or static setting values. This improves calibration accuracy and allows for real-time correction of the stroke in response to changes such as wear and temperature rise. At the same time, it effectively prevents collision damage by deducting a safety clearance from the calculated mechanical stroke and setting the operating endpoint to ensure that the mover will not cross the boundary and collide with the stator or mechanical end components during operation, thereby reducing the risk of wear and failure of mechanical components.

[0020] In addition, the present invention also provides real-time identification and closed-loop control of cavitation in the technical solution. The cavitation status is detected in real time by using frequent collisions at the upper end as the criterion, and is linked with the closed-loop adaptive adjustment of stroke rate. When a cavitation trend is detected, the stroke rate can be automatically reduced, and when it is confirmed that there is no cavitation, the stroke rate can be gradually increased, thus taking into account both cavitation prevention and oil production efficiency improvement.

[0021] The stroke-adaptive control cabinet provided by this invention enables the linear motor stroke to be detected with high precision using software and the corresponding control program to be adaptively matched, all while using the same set of hardware. This achieves the standardization of the control cabinet, which simplifies the daily maintenance workload of oil fields and greatly reduces the number of spare parts. Attached Figure Description

[0022] The advantages of the above and additional aspects of the present invention will become apparent and readily understood in the description of the embodiments in conjunction with the following drawings, wherein:

[0023] Figure 1This is a flowchart of the stroke adaptive control method of the submersible linear motor control cabinet according to an embodiment of the present invention;

[0024] Figure 2 This is a flowchart of the evacuation monitoring algorithm for an adaptive control method for a submersible linear motor control cabinet according to an embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of the submersible linear motor structure in an adaptive control method for a submersible linear motor control cabinet according to an embodiment of the present invention.

[0026] Figure 4 This is a linear motor stroke adaptive process of an adaptive control method for a submersible linear motor control cabinet according to an embodiment of the present invention;

[0027] Figure 5 This is a stroke adaptive test waveform diagram of the adaptive control method of the submersible linear motor control cabinet according to an embodiment of the present invention. Detailed Implementation

[0028] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other.

[0029] In the following description, many specific details are set forth in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0030] like Figure 3 As shown, the submersible linear motor mainly consists of a stator and a mover. The stator is a fully enclosed hollow cylindrical structure, and the mover is a solid cylindrical structure with a diameter smaller than the inner diameter of the stator. The submersible linear motor has a control cabinet outside the stator, which contains some control or monitoring modules. The control cabinet outputs control energy to the stator and mover through the three-phase voltage connection of the stator, driving the mover to reciprocate up and down inside the stator.

[0031] Currently, oilfields use various specifications of submersible linear motors, each with a different stroke. For example, the commonly used 1140V linear motor has a stroke of 1380mm, while the 660V linear motor has a stroke of 1080mm. In actual use in oilfields, different motors are matched with different control cabinets to accommodate different strokes. This mixed use of multiple control cabinets makes daily maintenance in oilfields extremely cumbersome, and the spare parts models are also very complex.

[0032] This embodiment provides an adaptive control method for a submersible linear motor control cabinet, the method comprising:

[0033] Before the initial calibration of the submersible linear motor, the control cabinet of the submersible linear motor is placed in the calibration-ready state according to the preset parameters. Ensure that the collision monitoring module, displacement detection module, drive output module and recording and storage module of the control cabinet are all powered on and in the working preparation state. Under the premise of ensuring safety and no mechanical abnormalities, the control cabinet outputs a preset three-phase AC voltage to the motor, so that the mover slowly moves downward from a random initial position. At the same time, the collision monitoring module is activated in real time to detect collision events between the mover and the stator.

[0034] The working mechanism of the collision monitoring module can be achieved by, for example, a collision detection method for a submersible linear motor provided by patent number CN106452270B.

[0035] When the collision monitoring module detects a lower-end collision, the control cabinet immediately stops outputting voltage to the motor, causing the mover to stop moving. This stopping position is defined in the control program as the zero point of the linear motor's mechanical travel. Figure 4 As shown, this stage corresponds to the time period from 0 to t0; subsequently, the mover is held at the zero point for several seconds to complete the initial positioning and steady-state signal acquisition, corresponding to the time period from t0 to t1.

[0036] After the zero-point dwell period ends, the control cabinet changes the phase sequence of the three-phase voltage while keeping the frequency and effective value unchanged, driving the mover to move upward. During the upward movement, the displacement detection module and the collision monitoring module work synchronously to record the displacement information and collision events of the mover relative to the zero point in real time. When an upper collision is detected, the control cabinet stops outputting voltage and records the upper collision position as the upper end point of the motor's mechanical stroke. This process corresponds to the time period t1 to t2.

[0037] Based on the displacement and drive frequency data recorded by the control cabinet, the control program calculates the mechanical stroke S0 of the linear motor:

[0038]

[0039] In the above formula, S0 is the mechanical stroke of the linear motor, n is the total number of switching cycles, and v k The linear motor's operating speed corresponding to each switching cycle; because the linear motor is a permanent magnet synchronous motor, its speed v k =2τf k In the formula f k Let τ be the three-phase voltage frequency of the drive motor during each switching cycle, τ be the motor pole pitch, and t be a mechanical constant; s The switching cycle of a linear motor control cabinet using PWM control is typically several microseconds to tens of microseconds; the motor pole pitch τ and the switching cycle ts Both are constants, while the three-phase voltage frequency f corresponding to each switching cycle is... k The preset value of the control program is known to the control program.

[0040] To avoid frequent collisions between the mover and the motor stator during actual operation, which could lead to mechanical damage, after obtaining the mechanical stroke S0, the control program determines the upper and lower endpoints of the running stroke according to the set collision-free interval h, where h is the safe distance between the mover's running endpoint and the corresponding mechanical endpoint of the motor. The lower endpoint of the running stroke is located at a distance h from the zero point, and the upper endpoint of the running stroke is located at a distance h from the upper mechanical endpoint. That is, the total effective running stroke is S0-2h.

[0041] The control cabinet drives the mover downwards to the lower endpoint h from zero and stops. After waiting for a preset dwell time at the lower endpoint of the travel stroke, the control cabinet drives the mover upwards to the upper endpoint h from the upper endpoint and stops. This upper endpoint position is recorded as the upper endpoint of the travel stroke. Afterwards, the mover will stably reciprocate between the upper and lower endpoints of the travel stroke according to the set drive parameters. This process corresponds to the attached... Figure 4 The period after t3.

[0042] In actual long-term operation, in order to overcome stroke drift that may be caused by mechanical wear, temperature rise or environmental changes, the control program re-executes the above stroke calibration and running stroke settings according to the set correction cycle or trigger conditions (such as when the operation reaches a certain number of times or when abnormal collision frequency is detected), so as to dynamically correct the mechanical stroke S0 and the running endpoint, and ensure the effectiveness of the collision-free interval h and the safety of operation.

[0043] Currently, frontline maintenance personnel rely on statistical data of daily oil production from oil wells to determine whether the current oil production rate is appropriate, i.e., whether the corresponding linear motor stroke rate is appropriate. Then, they adjust the stroke rate every quarter or every six months based on the oil production situation.

[0044] The adjustment logic for the linear motor stroke rate is as follows: if the overall trend of oil production decreases, it indicates that the oil well production rate has decreased or the stroke rate is too high, so the stroke rate should be lowered accordingly; if the daily oil production remains basically unchanged, it indicates that the current oil production rate is not lower than the oil production rate, so the stroke rate can be increased by one level.

[0045] This adjustment method, which is done quarterly or semi-annually, has too much lag and is not conducive to fully utilizing the oil production capacity of oil wells. Wells will either be frequently depleted or remain in a state of insufficient oil production for a long time until periodic statistical adjustments are made. In addition, the adjustment range depends on human experience, and often the adjustment is too excessive or insufficient, which will still result in the wells being depleted or insufficiently produced after the adjustment.

[0046] like Figure 1As shown, this invention provides a stroke adaptive control process for a submersible linear motor. The stroke adaptive control aims to maximize the oil well productivity. After completing the stroke adaptive calibration, the control cabinet enters the stroke adaptive cycle. First, the initial stroke value m times / minute is set as the initial operating frequency of the system, and parameters such as the pumping air monitoring module, the stroke adjustment interval T0 (observation period, generally in weeks), and the stroke adjustment step size a (generally 0.1 to 0.5 times / minute) are set. The system starts running with the stroke value m and simultaneously starts the pumping air monitoring program for real-time monitoring.

[0047] The stroke adjustment strategy is as follows: Within each stroke adjustment interval T0, the control program adjusts the stroke m by increasing or decreasing based on the pumping vent monitoring results. If no pumping vent event is detected during T0 (i.e., the pumping vent monitoring module does not trigger a judgment), the current stroke is considered to be below the pumping speed threshold that the well can withstand, and the control program increases the stroke m to m+a. If a pumping vent event is detected during T0, the current stroke is considered to be too fast, causing pumping vent, and the control program decreases the stroke m to ma. After adjustment, the program continues to run with the new stroke value and repeats the pumping vent monitoring and stroke adjustment cycle. The above adjustment cycle continues to run until the preset operation termination condition is reached or manual intervention is required.

[0048] The pumping cavitation monitoring module is used in the stroke adaptive control process, such as... Figure 2 As shown, the present invention also provides an algorithm for monitoring the cavitation of a submersible linear motor, and the cavitation monitoring module uses this algorithm.

[0049] The cavitation monitoring algorithm determines whether an oil well has cavitated based on the typical characteristic of "frequent collisions of the mover at the upper end during cavitation": once the oil production rate exceeds the oil well production rate, the oil level in the well will gradually drop until it is below the oil pump inlet, and then cavitation will occur. This causes the linear motor driving the oil pump to be unbalanced in force during the upward running phase, and thus the mover and the stator of the linear motor will frequently collide at the upper end in a short period of time (generally, the collision will occur in 5 reciprocating cycles), which greatly exceeds the normal collision frequency (generally, a collision will only occur once every few hundred reciprocating cycles).

[0050] Specifically, the cavitation monitoring program establishes a cavitation counter and initializes it to 0. In each running loop, if a collision is detected at the upper end of the mover, the cavitation counter is incremented by 1. The monitoring program counts the number of upper-end collisions within a given statistical window or a certain number of repetitions and compares this count with a threshold N0. If the number of upper-end collisions within the statistical window is greater than or equal to the threshold N0, a cavitation is determined, and the cavitation counter is cleared. Otherwise, the count continues to accumulate, or the counter is reset outside the window according to a set rule. The cavitation determination is based on the spatial location of the collision event, i.e., only upper-end collisions are recorded, and the frequency of collision events is used to improve the specificity of the determination, avoiding misjudging normal, occasional collisions as cavitation.

[0051] like Figure 5 As shown, this figure displays the waveforms from the stroke adaptive experiment. The yellow waveform represents the motor voltage, and the blue waveform represents the motor current. The upper rectangle in the figure provides an overview of the waveforms, while the lower rectangle shows a magnified image of a selected portion of the overview waveform. The time frame from left to right in the figure corresponds to the start of the operation. The shorter waveform on the far left corresponds to the mover starting from a random position and stopping when a collision is detected. To reduce the intensity of the collision between the mover and stator, the mover speed is low during this stage (drive voltage frequency does not exceed 5Hz, and the yellow voltage waveform in the figure is relatively sparse). After stopping and waiting for a period of time, the motor reverses its direction of operation and runs upward at a set frequency until a collision is detected and it stops. It can be seen that the motor runs for the longest time at this point, so there is still a collision in this stage, and the motor speed is still low (drive voltage frequency does not exceed 5Hz, and the yellow voltage waveform is relatively sparse). After stopping and reversing again, the motor runs downward again until it stops at a certain safe distance (60mm) from the lower endpoint. Since there is no collision in this stage, the motor speed can be controlled to be faster (drive voltage frequency not lower than 10Hz, and the yellow voltage waveform is relatively dense) to achieve rapid oil production. After stopping and reversing, the motor runs upward to a safe distance (60mm) from the endpoint and stops. The motor then cycles infinitely between the upper and lower safe points.

[0052] While implementing evacuation monitoring and stroke adaptive control, the control cabinet should maintain real-time acquisition and storage of key operating parameters such as collision events, displacement curves, drive frequency, power and current. If abnormal multiple collisions or abnormal drive current are detected, the fault protection logic should be triggered and the system should enter the safe shutdown or alarm mode according to the preset program. At the same time, the event should be recorded for subsequent fault diagnosis and correction.

[0053] In summary, this invention proposes an adaptive control method for a submersible linear motor control cabinet, the method comprising:

[0054] Before the first calibration, the control cabinet of the submersible linear motor is placed in the calibration state according to the preset parameters, and the collision monitoring module, displacement detection module, drive output module and recording and storage module are powered on and put into the working preparation state.

[0055] The control cabinet outputs a preset three-phase AC voltage to the motor, causing the mover to slowly move downward from a random initial position. At the same time, the collision monitoring module detects collision events between the mover and the stator in real time. When a collision is detected at the lower end, the output voltage is stopped and the stopping position is defined as the mechanical travel zero point of the linear motor in the control program. The mover is held at the zero point for several seconds to complete the initial positioning and steady-state signal acquisition.

[0056] The phase sequence of the three-phase voltage is changed to make the mover move upward. When moving upward, the displacement detection module and the collision monitoring module work synchronously to record the displacement information and collision events of the mover relative to the zero point in real time. When the upper collision is detected, the output voltage is stopped and the upper collision position is recorded as the upper end point of the mechanical stroke. Based on the displacement and drive frequency data recorded by the control cabinet, the mechanical stroke S0 of the linear motor is calculated.

[0057] The upper and lower endpoints of the mechanical stroke are both reduced inward by a preset collision-free interval h. The reduced upper and lower endpoints are used as the official upper and lower endpoints of the running stroke. The total effective running stroke is S0-2h, so that the mover can reciprocate stably between the official upper and lower endpoints according to the set drive parameters.

[0058] The control cabinet performs adaptive stroke adjustment according to the set stroke adaptive control process: setting the initial stroke m, the cavitation monitoring module, the stroke adjustment interval T0, and the stroke adjustment step size a; within each stroke adjustment interval T0, the stroke m is adjusted by increasing or decreasing according to the cavitation monitoring results; when no cavitation event is detected during T0, m increases to m+a; when a cavitation event is detected during T0, m decreases to ma; and the operation continues with a new stroke and the above cycle is repeated.

[0059] The cavitation monitoring module is implemented by a cavitation monitoring algorithm, which includes: the cavitation monitoring program establishes a cavitation counter and initializes it to 0; in each running loop, if a collision is detected on the upper end of the mover, the cavitation counter is incremented by 1; the monitoring program counts the number of collisions within a given statistical window or a certain number of repetitions and compares it with a threshold N0: when the number of collisions within the statistical window is greater than or equal to the threshold N0, it is determined that a cavitation has occurred and the cavitation counter is cleared; otherwise, it continues to accumulate or the counter is reset according to the set rules outside the window.

[0060] The steps in this invention can be adjusted, combined, or deleted according to actual needs.

[0061] The units in the device of the present invention can be merged, divided, or reduced according to actual needs.

[0062] Although the invention has been disclosed in detail with reference to the accompanying drawings, it should be understood that these descriptions are merely exemplary and not intended to limit the application of the invention. The scope of protection of the invention is defined by the appended claims and may include various modifications, alterations, and equivalents made to the invention without departing from the scope and spirit of the invention.

Claims

1. An adaptive control method for a submersible linear motor control cabinet, characterized in that, The method includes: Before the first calibration, the control cabinet of the submersible linear motor is placed in the calibration state according to the preset parameters, and the collision monitoring module, displacement detection module, drive output module and recording and storage module are powered on and put into the working preparation state. The control cabinet outputs a preset three-phase AC voltage to the motor, causing the mover to slowly move downward from a random initial position. At the same time, the collision monitoring module detects collision events between the mover and the stator in real time. When a collision is detected at the lower end, the output voltage is stopped and the stopping position is defined as the mechanical travel zero point of the linear motor in the control program. The mover is held at the zero point for several seconds to complete the initial positioning and steady-state signal acquisition. The phase sequence of the three-phase voltage is changed to make the mover move upward. When moving upward, the displacement detection module and the collision monitoring module work synchronously to record the displacement information and collision events of the mover relative to the zero point in real time. When the upper collision is detected, the output voltage is stopped and the upper collision position is recorded as the upper end point of the mechanical stroke. The mechanical stroke S0 of the linear motor is calculated based on the displacement and drive frequency data recorded by the control cabinet. The upper and lower endpoints of the mechanical stroke are both reduced inward by the preset collision-free interval h. The reduced upper and lower endpoints are used as the formal upper and lower endpoints of the running stroke. The total effective running stroke is S0-2h, so that the mover can reciprocate stably between the formal upper and lower endpoints according to the set drive parameters. The control cabinet performs adaptive stroke adjustment according to the set stroke adaptive control process: setting the initial stroke m, the cavitation monitoring module, the stroke adjustment interval T0, and the stroke adjustment step size a; within each stroke adjustment interval T0, the stroke m is adjusted by increasing or decreasing according to the cavitation monitoring results; when no cavitation event is detected during T0, m increases to m+a; when a cavitation event is detected during T0, m decreases to ma; and the operation continues with a new stroke and repeats the above cycle. The vacuum monitoring module is implemented by a vacuum monitoring algorithm, which includes: The cavitation monitoring program establishes a cavitation counter and initializes it to 0. In each running loop, if a collision is detected on the upper end of the mover, the cavitation counter is incremented by 1. The monitoring program counts the number of collisions within a given statistical window or a certain number of repetitions and compares it with the threshold N0. When the number of collisions within the statistical window is greater than or equal to the threshold N0, it is determined that cavitation has occurred and the cavitation counter is cleared. Otherwise, it continues to accumulate or the counter is reset according to the set rules outside the window.

2. The adaptive control method for the submersible linear motor control cabinet as described in claim 1, characterized in that, The formula for calculating the mechanical stroke S0 of a linear motor is: ； In the formula, S0 is the mechanical stroke of the linear motor, n is the total number of switching cycles, and v k The linear motor's operating speed corresponding to each switching cycle; because the linear motor is a permanent magnet synchronous motor, its speed v k =2τf k In the formula f k Let τ be the three-phase voltage frequency of the drive motor during each switching cycle, τ be the motor pole pitch, and t be a mechanical constant; s The switching cycle of the linear motor control cabinet using PWM control ranges from several microseconds to tens of microseconds; the motor pole pitch τ and the switching cycle t s Both are constants, while the three-phase voltage frequency f corresponding to each switching cycle is... k The preset value of the control program is known to the control program.

3. The adaptive control method for the submersible linear motor control cabinet as described in claim 1, characterized in that, When the control cabinet changes the phase sequence of the three-phase voltage from decreasing to increasing, the frequency and effective value remain unchanged.

4. The adaptive control method for the submersible linear motor control cabinet as described in claim 1, characterized in that, While implementing evacuation monitoring and stroke adaptive control, the control cabinet maintains real-time acquisition and storage of key operating parameters such as collision events, displacement curves, drive frequency, power and current. When multiple abnormal collisions or abnormal drive currents are detected, the fault protection logic is triggered and the system enters a safe shutdown or alarm mode according to a preset program. At the same time, the events are recorded for subsequent fault diagnosis and correction.

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