Steering engine control method based on integral saturation optimization and commutation differential enhancement

Abstract

The invention discloses a steering engine control method based on integral saturation optimization and commutation differential enhancement, belongs to the technical field of motor control, and solves the problems of integral saturation, commutation impact and steady-state jitter of traditional PID control. The method comprises the following steps: generating a real-time position error according to a real-time target position and a real-time position feedback signal of the electric steering engine; judging whether the electric steering engine enters a steady state or not according to the real-time position error and the change of the real-time target position; if the electric steering engine does not enter the steady state, amplitude limiting output is carried out on a position ring according to the real-time position error and the change rate of the real-time target position, so that direction and commutation control and amplitude limiting output of a current ring are carried out on the electric steering engine, and the electric steering engine is driven to operate; and if the electric steering engine enters the steady state, the output of the position loop is controlled to be 0, the integral term of the current loop is reset, and the electric steering engine does not run.

Description

Technical Field

[0001] This invention relates to the field of motor control technology, specifically to a servo motor control method based on integral saturation optimization and commutation differential enhancement, which is particularly suitable for servo motor systems requiring high-precision position control. Background Technology

[0002] Servo motors, as high-precision servo actuators, are widely used in robot joint driving, aerospace control surface adjustment, and precision instrument attitude control. Their core performance indicators are the speed, stability, and smoothness of position tracking. Current mainstream servo motor systems mostly employ PID (Proportional-Integral-Derivative) control algorithms and achieve precise control through a multi-stage closed-loop architecture consisting of position, velocity, and current loops. However, traditional PID control has significant drawbacks under the unique operating conditions of servo motors, specifically manifested in the following three key issues: (1) Integral saturation problem: Output overshoot during position locking or commutation process Servo motors are limited by their mechanical structure (such as maximum angle of rotation and maximum torque), resulting in physical limitations on their control output. During the position lock-in phase (when the target position remains unchanged but a small steady-state error exists) or the commutation process (when the target position reverses), the integral term of a traditional PID controller can become excessively accumulating due to the continuous accumulation of errors ("integral saturation"). For example, when the servo motor has reached its mechanical limit but the target position has not yet been adjusted, the integral term will continue to increase to "eliminate the error." This causes the integral term to release redundant energy before the output response error changes when the target position reverts, leading to significant overshoot or oscillation, which severely affects the position lock-in accuracy.

[0003] (2) Commutation impact problem: differential disturbance and mechanical vibration during direction switching When a servo motor (such as a permanent magnet synchronous motor or a stepper motor) switches direction (commutates), the switching of the three-phase winding current causes instantaneous abrupt changes in feedback signals such as position and speed (e.g., Hall sensor signal jumps, current detection ripple). Traditional PID controllers calculate the derivative term directly based on the instantaneous rate of change of error, making them extremely sensitive to such abrupt signals. This results in sharp differential output pulses, causing instantaneous torque surges in the motor, leading to mechanical jitter, gear meshing noise, or position overshoot during commutation. This not only reduces control smoothness but also exacerbates wear on transmission components.

[0004] (3) Steady-state jitter problem: Output fluctuation under small error When the servo motor approaches the target position (when the position following error is small), the output of a traditional PID controller may still continuously adjust due to small fluctuations in error (such as sensor noise or mechanical friction disturbances): the proportional term amplifies small errors, the derivative term captures high-frequency noise, and the integral term may slowly accumulate due to steady-state error, causing the output to oscillate slightly around the target value ("steady-state jitter"). This jitter is particularly noticeable in high-precision scenarios (such as aerospace control surface fine-tuning), which can reduce the system's position-keeping accuracy and even lead to resonance risks.

[0005] The root cause of the above problems lies in the fact that traditional PID control is not adapted to the mechanical constraints, commutation dynamic characteristics, and steady-state accuracy requirements of servo motors, making it difficult to balance integral saturation suppression, derivative disturbance rejection capability, and steady-state convergence. Therefore, there is an urgent need for a control method that integrates integral saturation optimization and commutation derivative enhancement to address the core shortcomings of traditional PID control in servo motor control and improve its overall performance in high-precision scenarios. Summary of the Invention

[0006] Based on the above analysis, the embodiments of the present invention aim to provide a servo control method based on integral saturation optimization and commutation derivative enhancement, in order to solve the problems of integral saturation, commutation shock and steady-state jitter in traditional PID control.

[0007] This invention discloses a servo motor control method based on integral saturation optimization and commutation differential enhancement, the method comprising: Real-time position error is generated based on the real-time target position and real-time position feedback signal of the electric servo motor; whether the electric servo motor has entered a steady state is determined based on the real-time position error and the change in the real-time target position. If the electric servo motor does not reach a steady state, the position loop is limited based on the real-time position error and the rate of change of the real-time target position, so as to control the direction and commutation of the electric servo motor and limit the output of the current loop to drive the electric servo motor to run. If the electric servo motor enters a steady state, the output of the control position loop will be 0, the integral term of the current loop will be cleared, and the electric servo motor will not run.

[0008] Based on the above solution, the present invention also makes the following improvements: Furthermore, if the electric servo motor does not reach a steady state, execute: The position loop is output with limited amplitude based on the real-time position error and the rate of change of the real-time target position. The position loop's limiting output is used as the speed output reference to determine the real-time speed output and to control the direction and commutation of the electric servo motor. The real-time speed output is used as the real-time target current of the current loop, and the current loop is limited. The limited output of the current loop is used as the motor drive signal to drive the servo motor.

[0009] Furthermore, based on the real-time position error and the rate of change of the real-time target position, the position loop is limited and output, and the following is executed: The real-time position error is processed using PID control based on integral saturation optimization. Calculate the velocity feedforward of the position loop based on the rate of change of the real-time target position; The limiting output of the position loop is obtained by combining the proportional, integral, and differential terms of the position loop with the velocity feedforward.

[0010] Furthermore, the proportional term of the position ring Represented as: (1) in, This is the scaling factor for the position loop. Indicates real-time position error; Integral term of the position ring Represented as: (2) in, For the integral coefficients of the position loop, This is the integral term of the position loop from the previous cycle; , These are the limiting output and pre-saturation output of the position loop in the previous cycle, respectively. Differential term of position loop Represented as: (3) in, For the differential coefficients of the position loop, This is the proportional term of the position ring of the previous cycle.

[0011] Furthermore, the velocity feedforward of the position loop Represented as: (4) in, For the real-time target location, This is the target position for the previous cycle; Then, make the following judgments and update the velocity feedforward of the position loop. : (5).

[0012] Furthermore, by summing the proportional, integral, and differential terms with the velocity feedforward, the pre-saturation output of the position loop for the current cycle is obtained. : (6) Limiting the pre-saturated output of the position loop yields the limited output of the position loop. : (7) in, , These are the maximum and minimum limiting outputs of the position loop, respectively.

[0013] Furthermore, using the position loop's limiting output as the speed output reference, the real-time speed output is determined, and the electric servo motor is used for direction and commutation control, executing: Determine if the speed output reference is non-negative. If it is, control the electric servo to rotate in the forward direction, and maintain the speed output reference in real time. Otherwise, control the electric servo to rotate in the reverse direction, and take the absolute value of the speed output reference in real time. Determine whether the rotation direction of the electric servo motor in the current cycle is opposite to that in the previous cycle. If so, trigger the electric servo motor to commutate and clear all integral terms of the current loop.

[0014] Furthermore, the triggering of the electric servo motor to commutate executes: When the electric servo motor rotates in the forward direction, the commutation pointer uses the reference position value detected by the Hall sensor; When the electric servo motor rotates in the reverse direction, the commutation pointer is the Hall sensor reference position value plus 3; If the commutation pointer is greater than or equal to 6, subtract 6 from the commutation pointer for correction.

[0015] Furthermore, using the real-time speed output as the real-time target current of the current loop, the current loop is limited and the following steps are executed: Real-time current error is generated based on the real-time target current and the real-time current feedback signal; The real-time current error is processed by PI based on integral saturation optimization; Based on the PI processing results of the real-time current error, the current loop's limited output is obtained.

[0016] Furthermore, the step of determining whether the electric servo motor has entered a steady state based on the real-time position error and the change in the real-time target position is executed as follows: The system determines whether the absolute value of the real-time position error is less than the preset error threshold and whether the real-time target position of the current cycle is consistent with the real-time target position of the previous cycle. If both conditions are met, the electric servo motor enters a steady state; otherwise, the electric servo motor does not enter a steady state.

[0017] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects: The servo control method based on integral saturation optimization and commutation derivative enhancement provided by this invention effectively solves the problems of integral saturation, commutation shock and steady-state jitter in traditional PID control through triple collaborative optimization, as detailed below.

[0018] (1) Integral saturation adaptive suppression strategy (to solve the overshoot problem) To address the issue of excessive accumulation of the integral term during position locking or commutation, a technical concept of "pausing integration when the output is saturated and allowing integral accumulation when it is not saturated" is employed. This involves real-time monitoring of the position loop and current loop outputs to determine if they have reached mechanical limits (such as maximum angle or maximum current) and whether the system has entered a saturation state. When the output is not saturated, the integral term accumulates normally according to the error. When the output is saturated, the integral term maintains its historical value and stops accumulating new errors, thus avoiding redundant energy buildup. The benefits include reduced overshoot during position recovery or commutation and shorter saturation recovery time.

[0019] (2) Differential smoothing enhancement strategy for commutation process (to solve the commutation shock problem) To suppress differential disturbances during direction switching, optimizations are made in both calculation methods and commutation adaptation. Firstly, the differential term calculation logic is improved by calculating the differential term based on the rate of change of the proportional term (the difference between the current proportional term and the proportional term of the previous cycle), replacing the traditional instantaneous error rate of change. This filters high-frequency noise and enables commutation detection and dynamic adjustment. Secondly, commutation is determined by comparing the current and previous direction states. Upon commutation, the current loop integral term is immediately cleared, and the differential term calculation reference is reset, avoiding differential spikes caused by signal abrupt changes. This reduces torque impact and mechanical vibration during commutation, improving control smoothness.

[0020] (3) Steady-state small error precise locking strategy (to solve the steady-state jitter problem) To address output fluctuations under small errors, precise locking is achieved through threshold judgment: a preset position error threshold (corresponding to 1-2 times the mechanical resolution) is used. When the error is less than the threshold and the target position is stable, the system is considered to have entered a steady state. In steady state, the current loop integral term is cleared, limiting the position loop output to approach zero and avoiding output adjustments caused by minor disturbances. Position jitter is controlled within ±1 mechanical resolution, meeting the requirements for high-precision maintenance.

[0021] (4) Triple strategy synergy mechanism A cascaded synergy is achieved through a three-loop closed-loop architecture consisting of a position loop, a speed loop, and a current loop: the position loop dominates integral suppression and differential smoothing, outputting a stable speed command; since the actual working state of the servo motor does not involve speed control, the traditional speed closed loop is eliminated, and speed feedforward is added after the position loop; the current loop undertakes commutation integral clearing and steady-state optimization, transforming it into a smooth drive signal; multi-level closed-loop dynamic adaptation balances fast response and disturbance rejection capability.

[0022] In summary, the servo control method based on integral saturation optimization and commutation derivative enhancement provided by this invention optimizes the single PID control used in traditional servos. Compared with the traditional method, it can effectively suppress integral saturation to reduce overshoot, optimize the derivative characteristics during commutation to reduce mechanical shock, improve steady-state locking accuracy, and is compatible with various servo types. It does not require hardware modifications and is easy to implement in engineering.

[0023] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from what is particularly pointed out in the description and drawings. Attached Figure Description

[0024] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. Figure 1 A flowchart illustrating the servo control method based on integral saturation optimization and commutation differential enhancement provided in an embodiment of the present invention; Figure 2 A flowchart illustrating the servo control method based on integral saturation optimization and commutation differential enhancement provided in an embodiment of the present invention; Figure 3 A flowchart of the position loop control module provided in an embodiment of the present invention; Figure 4 A flowchart of the direction and commutation control module provided in an embodiment of the present invention; Figure 5 A flowchart of a current loop control module provided in an embodiment of the present invention. Detailed Implementation

[0025] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0026] This invention provides a servo control method based on integral saturation optimization and commutation differential enhancement, the flowchart of which is shown below. Figure 1 and Figure 2 As shown below, the specific implementation steps of this method are explained in detail.

[0027] Step S1: Generate a real-time position error based on the real-time target position and real-time position feedback signal of the electric servo motor; determine whether the electric servo motor has entered a steady state based on the changes in the real-time position error and the real-time target position.

[0028] Step S2: If the electric servo motor has not entered a steady state, the position loop is limited based on the real-time position error and the rate of change of the real-time target position, so as to control the direction and commutation of the electric servo motor and limit the output of the current loop to drive the electric servo motor to run.

[0029] Step S3: If the electric servo motor enters a steady state, the output of the control position loop is 0, the integral term of the current loop is cleared to zero, and the electric servo motor does not run.

[0030] Specifically, in step S1, the following operations are performed.

[0031] The system receives the real-time target position (issued in the form of a position command) from the host computer, and collects the real-time position feedback signal from the electric servo motor (an angle signal detected by the encoder and fed back through a position sensor). The real-time position feedback signal is divided by the number of pulses per channel of the encoder to obtain the real-time position feedback value. The difference between the real-time target position and the real-time position feedback value is taken as the real-time position error. .

[0032] (1) in, For the real-time target location, This is the real-time location feedback value.

[0033] (2) in, This represents the number of pulses per channel of the encoder, used to convert the angle signal into a position quantity with the same dimension as the target position command. This is the real-time position feedback signal of the electric servo motor detected by the encoder.

[0034] Preferably, in step S1, the electric servo motor is judged to have entered a steady state based on the real-time position error and the change in the real-time target position, and then the following is executed: The system determines whether the absolute value of the real-time position error is less than the preset error threshold and whether the real-time target position of the current cycle is consistent with the real-time target position of the previous cycle. If both conditions are met, the electric servo motor enters a steady state; otherwise, the electric servo motor does not enter a steady state.

[0035] The corresponding discriminant formula can be expressed as: (3) in, This indicates the real-time target position in the previous period. This indicates twice the encoder pulse resolution.

[0036] If the electric servo motor enters a steady state, i.e., step S3 is executed, the output of the position loop is 0, the integral term of the current loop is cleared to zero, and the electric servo motor does not run, avoiding output fluctuations caused by minor disturbances. It should be noted that ordinary PID controllers will still continuously adjust due to noise or steady-state error when there is a small error, resulting in output jitter; while this embodiment actively clears the integral term of the current loop and the output of the position loop by using threshold judgment, which can achieve high-precision locking without jitter.

[0037] The following is a detailed explanation of the control method when the electric servo motor has not entered a steady state in step S2.

[0038] Step S21: Limit the output of the position loop based on the real-time position error and the change in the real-time target position.

[0039] Perform the following operations.

[0040] In the specific implementation process, the function of step S21 is completed by the position loop control module, and the flowchart of the position loop control module is attached. Figure 3 As shown.

[0041] Step S211: Perform PID processing on the real-time position error based on integral saturation optimization.

[0042] The specific processing procedure is described below.

[0043] (1) Proportional term The proportional term of the position ring Represented as: (4) in, This is the scaling factor for the position ring.

[0044] (2) Integral term Integral term of the position ring Represented as: (5) in, For the integral coefficients of the position loop, This is the integral term of the position loop from the previous cycle; , These are the limiting output and pre-saturation output of the position loop in the previous cycle, respectively.

[0045] In this embodiment, the integral term is dynamically adjusted based on whether the position loop output reaches a preset saturation threshold (i.e., whether the output exceeds the mechanical limit): if If so, it indicates that the output is not saturated, and the integral term is obtained by superimposing the current integral coefficient and the position error with the historical integral terms; if This indicates that the output is saturated, and the integral term remains unchanged from the historical integral term to avoid excessive accumulation.

[0046] In short, this is a logic that dynamically determines whether the integral term continues to accumulate based on whether the output remains saturated: when the output remains saturated, the integral is allowed to accumulate normally; when the output de-saturates, the integral accumulation is paused (preserving the historical value). Ordinary PID integral terms constantly accumulate position errors, easily leading to integral saturation; this embodiment dynamically stops integral accumulation by controlling the output state, suppressing saturation at its source.

[0047] (3) Differential term Differential term of position loop Represented as: (6) in, For the differential coefficients of the position loop, This is the proportional term of the position ring of the previous cycle.

[0048] Existing methods for calculating differential terms rely directly on sudden error changes, which can easily amplify noise. This embodiment calculates differential terms indirectly through the rate of change of the proportional term, which can effectively smooth high-frequency disturbances, suppress noise, and reduce the impact of sudden changes in feedback signals. It is especially suitable for signal jump scenarios during commutation and can further optimize the efficiency when adjusting PID coefficients.

[0049] Step S212: Calculate the velocity feedforward of the position loop based on the rate of change of the real-time target position.

[0050] Velocity feedforward of position loop Represented as: (7) in, This is the target position for the previous cycle. Indicates the period.

[0051] Then, make the following judgments and update the velocity feedforward of the position loop. : (8) The velocity feedforward calculation method proposed in this embodiment can enhance the dynamic response speed on the one hand, and explain the correction logic of velocity feedforward in the position loop scenario on the other hand. The core is to eliminate the "large difference in mathematical calculation" and retain the "real small changes in physical motion" to perform boundary correction on velocity feedforward and avoid abrupt changes when switching directions.

[0052] In formula (7), 1 represents the normalized range. In servo control, position commands are usually encoded periodically (such as an angle range of 0°~360°, or a normalized range of 0~1, where "1" represents 360°). When the servo jumps from 359° (corresponding to position command 0.997) to 1° (corresponding to position command 0.003), the mathematical position difference is 0.003 - 0.997 = -0.994, but the actual physical movement is only 2° (not a reverse rotation of 358°). At this time, "1" is used as a correction value, which is essentially to compensate for the "period difference" of the periodic jump: by adding 1 or subtracting 1, the "false large difference across the period" is corrected to the "actual small angle change" (as in the example above, -0.994 + 1 = 0.006, corresponding to an actual 2° positive movement). "0.5" is the critical value for determining whether a "periodic jump" occurs, and its setting is based on the physical movement limits of the servo motor. Generally, such a high speed cannot be achieved, so when the difference equals this value, compensation of 1 is needed. During normal movement, the maximum speed of the servo motor may only be 0.1 cycles / control cycles (36° / control cycle), far less than 0.5, requiring no correction. When the speed command is -0.8 (absolute value > 0.5), it is determined to be a cross-cycle jump, and corrected to 0.2 (corresponding to an actual forward movement of 72°) by +1, which conforms to physical reality. Ordinary PID controllers typically lack speed feedforward and rely solely on error feedback for adjustment, resulting in a lag in dynamic response. This invention improves response speed by applying the control quantity in advance through the target position change rate.

[0053] Step S213: Based on the proportional, integral, and differential terms of the position loop and the velocity feedforward, obtain the limiting output of the position loop.

[0054] Summing the proportional, integral, and differential terms with the velocity feedforward yields the position loop pre-saturation output for the current cycle. : (9) The pre-saturated output of the position loop is limited (to a preset maximum / minimum output range) to obtain the limited output of the position loop. : (10) in, , These are the maximum and minimum limiting outputs of the position loop, respectively.

[0055] Servo motors are limited by mechanical structure (such as maximum angle of rotation and maximum torque) or drive circuit capabilities (such as maximum current), and their actual executable control quantities have physical upper and lower limits. If theoretical calculations... Exceeding this range will result in the following consequences if the output is direct: mechanical component overload (e.g., gear jamming, motor stall); drive circuit overcurrent (e.g., power transistor damage); and control logic failure (e.g., instructions cannot be executed, leading to system instability). After limiting, It is always a valid instruction that the system can execute, balancing control precision and hardware security.

[0056] It should be noted that in this embodiment, the limiting logic complements the previously mentioned "maintaining the historical value of the integral term when the output is saturated": limiting is a "hard constraint at the physical layer" to ensure that the output does not exceed the limit; while integral saturation suppression is a "flexible optimization at the algorithm layer" to avoid excessive accumulation of the integral term due to output exceeding the limit. Together, they ensure the stable operation of the system under the constraints.

[0057] Therefore, this embodiment innovates on traditional PID from four dimensions: saturation suppression of integral term, noise immunity of derivative term, enhancement of speed feedforward, and steady-state locking, thus solving the core pain points in servo motor control.

[0058] Step S22: Using the limiting output of the position loop as the speed output reference, determine the real-time speed output and perform direction and commutation control on the electric servo motor.

[0059] Specifically, the operation in step S22 is completed by the direction and commutation control module, and the flowchart of the direction and commutation control module is attached. Figure 4 As shown, the specific explanation is as follows.

[0060] Step S221: Determine whether the speed output reference is non-negative. If yes, control the electric servo to rotate in the forward direction, and maintain the speed output reference in real time. Otherwise, control the electric servo to rotate in the reverse direction, and take the absolute value of the speed output reference in real time.

[0061] Specifically, the final output of the position loop serves as the speed output reference: If the speed output reference value is non-negative, the electric servo is determined to be rotating in the forward direction, and the speed output remains unchanged at the reference value; if it is negative, the servo is determined to be rotating in the reverse direction, and the speed output takes the absolute value of the reference value.

[0062] Real-time speed output Represented as: (11) like Then, control the electric servo motor to rotate in the forward direction, and the direction indicator will be displayed. ;otherwise, Control the electric servo motor to rotate in the opposite direction, directional indicator .

[0063] Traditional direction determination requires separate calculation of the direction based on the speed loop output or position error. This embodiment directly uses the position loop output as the speed reference, achieving coordinated determination of "position-speed-direction," simplifying the signal transmission link of multi-level closed loops. It reduces the calculation delay of independent speed loops, resulting in higher consistency between direction determination and position control response, making it particularly suitable for servo motor scenarios requiring rapid commutation.

[0064] Step S222: Determine whether the rotation direction of the electric servo motor in the current cycle is opposite to that in the previous cycle. If so, trigger the electric servo motor to commutate and clear all integral terms of the current loop.

[0065] In the specific implementation process, the commutation pointer (the motor moves in both directions, and the commutation pointer is used to determine the current direction of movement. The difference between a servo motor and a regular motor is that the commutation frequency is very high, and the direction changes frequently) is adjusted. When the electric servo motor rotates forward, the commutation pointer uses the reference position value detected by the Hall sensor; when the electric servo motor rotates in reverse, the commutation pointer is the Hall sensor reference position value plus 3 (to adapt to the three-phase winding state during reverse rotation); if the commutation pointer is greater than or equal to 6, the commutation pointer is subtracted by 6 for correction (to ensure that the pointer is within the effective range of 0-5, representing Hall 6 phases). Traditional commutation pointers need to be generated by complex Hall signal logic lookup tables (such as judging based on the combination of three-phase Hall states). This invention directly calculates it by "direction + fixed offset (+3)", adapting to the symmetry of the three-phase state during reverse rotation (the difference between the three-phase state in forward and reverse directions is 3). The commutation pointer calculation does not require a lookup table, the logic is simple and the real-time performance is high, avoiding the possible delay or state misjudgment of the traditional lookup table method, which is especially suitable for high-speed commutation scenarios.

[0066] In addition, compare the current rotation direction with the rotation direction of the previous control cycle (determined by the direction indicator): if the two are opposite (i.e., commutation has occurred), immediately clear the integral term and historical integral value of the current loop to avoid torque shock caused by integral accumulation during commutation. , Finally, the current rotation direction is saved as the historical direction for the next cycle. Unlike traditional PID controllers that only adjust the three-phase output state during commutation, ignoring the cumulative effect of the integral term (the sudden change in error during commutation can cause abnormal growth of the integral term), this embodiment binds commutation detection with integral clearing, actively eliminating redundant integral energy. This avoids torque shocks caused by the accumulation of the integral term during commutation, reduces mechanical vibration and wear on transmission components, and minimizes the increase in instantaneous current, thus improving commutation smoothness.

[0067] Step S23: Use the real-time speed output as the real-time target current of the current loop, and limit the output of the current loop; use the limited output of the current loop as the motor drive signal to drive the servo motor.

[0068] The specific implementation process of step S23 is carried out in the current loop control module, and the flowchart of the current loop control module is as follows: Figure 5 As shown.

[0069] Step S231: Generate real-time current error based on the real-time target current and the real-time current feedback signal.

[0070] First, the real-time target current of the current loop. .

[0071] Real-time acquisition of real-time current feedback signal from electric servo motor The difference between the target current command and the current feedback signal is calculated to obtain the real-time current error.

[0072] Real-time current error Represented as: (12) Step S232: Perform PI processing on the real-time current error based on integral saturation optimization.

[0073] (1) Proportional term The proportional term of the current loop Represented as: (13) in, This represents the proportionality coefficient of the current loop.

[0074] (2) Integral term Integral term of current loop for: (14) in, This represents the integral coefficient of the current loop. This represents the integral term of the current loop in the previous cycle; , These represent the current loop's limited output and pre-saturation output from the previous cycle, respectively.

[0075] In this embodiment, the current loop output is dynamically adjusted based on whether it reaches the saturation threshold: if If the output is not saturated, the integral term is the product of the current integral coefficient and the current error, plus the historical integral value; if If the output is saturated, the integral term will retain its historical integral value.

[0076] Step S233: Based on the PI processing result of the real-time current error, obtain the limited output of the current loop.

[0077] The pre-saturation output of the current loop is expressed as: (15) The pre-saturated output of the current loop is limited (limited to a preset maximum / minimum current range), resulting in a limited output of the current loop.

[0078] (16) in, , These represent the maximum and minimum values ​​of the current loop output limit, respectively, which correspond to the maximum and minimum allowable drive current of the electric servo motor.

[0079] The implementation process in step S3 is consistent with the anti-saturation strategy of the position loop. By dynamically stopping the integral accumulation through the output state, a multi-level anti-saturation collaboration of "position loop + current loop" is formed.

[0080] Those skilled in the art will understand that all or part of the processes of the methods described in the above embodiments can be implemented by a computer program instructing related hardware, and the program can be stored in a computer-readable storage medium. The computer-readable storage medium may be a disk, optical disk, read-only memory, or random access memory, etc.

[0081] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A rudder control method based on integral saturation optimization and commutation differential enhancement, characterized in that, The method comprises: generating a real-time position error according to a real-time target position of the electric rudder and a real-time position feedback signal; and determining whether the electric rudder enters a steady state according to the real-time position error and a change rate of the real-time target position; if the electric rudder does not enter the steady state, performing amplitude limiting output on a position loop according to the real-time position error and the change rate of the real-time target position, so as to perform direction and commutation control on the electric rudder and amplitude limiting output on a current loop, and drive the electric rudder to operate; if the electric rudder enters the steady state, controlling the output of the position loop to be 0, clearing the integral term of the current loop, and stopping the electric rudder from operating.

2. The rudder control method based on integral saturation optimization and commutation differential enhancement according to claim 1, characterized in that, if the electric rudder does not enter the steady state, performing: performing amplitude limiting output on the position loop according to the real-time position error and the change rate of the real-time target position; determining a real-time speed output by taking the amplitude limiting output of the position loop as a speed output reference, and performing direction and commutation control on the electric rudder; performing amplitude limiting output on the current loop by taking the real-time speed output as a real-time target current of the current loop; driving the rudder motor to operate by taking the amplitude limiting output of the current loop as a motor driving signal.

3. The rudder control method based on integral saturation optimization and commutation differential enhancement according to claim 2, characterized in that, performing amplitude limiting output on the position loop according to the real-time position error and the change rate of the real-time target position, which comprises: performing PID processing on the real-time position error based on integral saturation optimization; calculating a speed feedforward of the position loop according to the change rate of the real-time target position; obtaining the amplitude limiting output of the position loop according to a proportional term, an integral term and a differential term of the position loop and the speed feedforward.

4. The rudder control method based on integral saturation optimization and commutation differential enhancement according to claim 3, wherein The proportional term of the position loop is represented as: (1) wherein, is a proportional coefficient of the position loop, denotes the real-time position error; Integral term of position loop is expressed as: (2) wherein is an integral coefficient of the position loop, is an integral term of the position loop of the previous cycle; , are the clipped output and the pre-saturation output of the position loop of the previous cycle, respectively. The differential term of the position loop is represented as: (3) wherein, is a differential coefficient of the position loop, is a proportional term of the position loop of the previous cycle.

5. The integrator saturation-based optimization and phase-differentiated augmentation-based steering engine control method according to claim 4, characterized by, Position loop velocity feed forward is represented as: (4) wherein, is the target position of the previous cycle, is the target position of the previous cycle; And the following judgment, update the position ring speed feedforward : (5)。 6. The integrator saturation-based optimization and phase-differentiated augmentation-based steering engine control method according to claim 5, characterized by, Summing the proportional, integral, derivative terms and the velocity feedforward to obtain the position loop pre-saturation output for the current cycle : (6) The position loop pre-saturation output is limited to obtain a limited output of the position loop : (7) wherein, , are the maximum, minimum clipped outputs of the position loop, respectively.

7. The integrator saturation-based optimization and phase-differentiated augmentation-based steering engine control method according to claim 6, characterized by, determining the real-time speed output by taking the amplitude limiting output of the position loop as the speed output reference, and performing direction and commutation control on the electric rudder, which comprises: judging whether the speed output reference is non-negative, if yes, controlling the electric rudder to rotate in a forward direction, and keeping the real-time speed output as the speed output reference; otherwise, controlling the electric rudder to rotate in a reverse direction, and taking the absolute value of the speed output reference as the real-time speed output; judging whether the rotating direction of the electric rudder in a current period is opposite to that in a previous period, if yes, triggering commutation of the electric rudder, and clearing all integral terms of the current loop.

8. The integrator saturation-based optimization and phase-differentiated augmentation based steering engine control method according to claim 7, characterized in that, the triggering of the commutation of the electric rudder comprises: when the electric rudder rotates in the forward direction, the commutation pointer adopts a reference position value detected by a Hall sensor; when the electric rudder rotates in the reverse direction, the commutation pointer is the reference position value of the Hall sensor plus 3; if the commutation pointer is greater than or equal to 6, the commutation pointer is corrected by subtracting 6.

9. The integrator saturation-based optimization and phase-differentiated augmentation-based steering engine control method according to claim 8, characterized by, performing amplitude limiting output on the current loop by taking the real-time speed output as the real-time target current of the current loop, which comprises: generating a real-time current error according to the real-time target current and a real-time current feedback signal; performing PI processing on the real-time current error based on integral saturation optimization; obtaining the amplitude limiting output of the current loop according to the PI processing result of the real-time current error.

10. The integrator-saturation-based optimization and phase-differentiation- enhanced rudder control method according to any one of claims 1-9, characterized in that, the determining of whether the electric rudder enters the steady state according to the real-time position error and the change of the real-time target position comprises: judging whether the absolute value of the real-time position error is less than a preset error threshold, and whether the real-time target position in the current period is consistent with that in the previous period, if both are satisfied, the electric rudder enters the steady state; otherwise, the electric rudder does not enter the steady state.

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