Method for adaptive adjustment of feedforward parameters of vector control system of permanent magnet synchronous motor

Abstract

A method for adaptively adjusting feedforward parameters of a vector control system of a permanent magnet synchronous motor, comprising the following steps: 1) setting an adaptive adjustment time threshold and a relationship curve segment number threshold; 2) segmenting a current-inductance relationship curve; 3) when the duration of the permanent magnet synchronous motor vector control system in a stable working condition is not less than the adaptive adjustment time threshold, adaptively adjusting the current loop feedforward parameters according to the following steps: 3-1) judging that the current direct-axis target current is in the n-th segment of the direct-axis current-inductance relationship curve and the current quadrature-axis target current is in the m-th segment of the quadrature-axis current-inductance relationship curve; 3-2) calculating the current direct-axis target voltage and the current quadrature-axis target voltage; 3-3) calculating the direct-axis inductance theoretical value and the quadrature-axis inductance theoretical value; 3-4) calculating the direct-axis feedforward parameter deviation percentage and the quadrature-axis feedforward parameter deviation percentage; and 3-5) calculating an end point update value to form an updated current-inductance relationship curve.

Description

Technical Field

[0001] This invention relates to the field of permanent magnet synchronous motors, and more specifically to a method for adaptively adjusting the feedforward parameters of a vector control system for a permanent magnet synchronous motor. Background Technology

[0002] Permanent magnet synchronous motors use permanent magnets for excitation, which simplifies the motor structure, reduces processing and assembly costs, and eliminates the need for slip rings and brushes that are prone to problems, thus improving the reliability of motor operation. Furthermore, since no excitation current is required, there is no excitation loss, which improves the efficiency and power density of the motor.

[0003] Currently, vector control systems for permanent magnet synchronous motors are widely used in pure electric vehicles and hybrid electric vehicles to achieve high-precision, high-dynamic-performance, and wide-range speed regulation or positioning control. Their control flow is as follows: Figure 1 As shown, firstly, based on the target speed and real-time speed of the motor output, the theoretically required direct-axis target current is calculated through PI closed-loop regulation. Cross-axis target current Then the three-phase currents i of phases A, B, and C collected by the current sensor A i B i C i in the αβ coordinate system after Clarke coordinate transformation α and i β Then transform i α and i β The direct-axis feedback current i is transformed from the Park coordinate system to the dq coordinate system. d and quadrature axis feedback current i q Next, the direct-axis target current will be... Cross-axis target current and direct-axis feedback current i d and quadrature axis feedback current i q Perform closed-loop control to obtain the direct-axis target voltage. quadrature axis target voltage Finally, the target voltage in the dq coordinate system is obtained through the inverse Park transform. and Then, the duty cycles of phases A, B, and C are calculated using space vector pulse width modulation (SVPWM), and modulated into three-phase voltage signals U for phases A, B, and C by driving the IGBTs of the three-phase inverter. A U B U C Loaded on the three-phase lines of the stator of the permanent magnet synchronous motor.

[0004] Therefore, one of the key aspects of vector control for permanent magnet synchronous motors is the control of the current loop. The control of the current loop mainly consists of feedforward parameters and closed-loop PI regulation. The accuracy of the feedforward parameters directly affects the responsiveness, stability, and reliability of the system. If the feedforward parameters are incorrect, it can easily cause the system to lose control, resulting in torque and speed fluctuations and triggering faults.

[0005] Currently, both domestic and international permanent magnet synchronous motor vector control systems use a single setpoint, simulated values ​​from motor parameter curves, or measured values ​​obtained through bench tests with a single / limited sample size as feedforward parameters for the vector control system. This makes it difficult to guarantee the accuracy of the feedforward parameters, and it cannot cover the system's multiple sample sizes and entire life cycle. Inaccurate feedforward parameters still lead to problems such as slow system response and large torque / speed fluctuations. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies by providing a method for adaptively adjusting the feedforward parameters of a permanent magnet synchronous motor vector control system. This method can automatically and accurately calculate the feedforward parameter curves—direct-axis / quadrature-axis current-inductance relationship curves—throughout the entire lifecycle of the permanent magnet synchronous motor vector control system. It eliminates the cumbersome process of acquiring feedforward parameter bench data, increases the proportion of current loop feedforward parameters, reduces the proportion of PI closed-loop regulation, and improves the responsiveness, stability, and reliability of the entire system.

[0007] The objective of this invention is achieved through the following scheme: a method for adaptively adjusting the feedforward parameters of a permanent magnet synchronous motor vector control system, comprising the following steps:

[0008] 1) Set the adaptive adjustment time threshold and the threshold for the number of segments in the relationship curve;

[0009] 2) Divide the direct-axis current-inductance relationship curve into N segments and the quadrature-axis current-inductance relationship curve into M segments, where N and M are not greater than the threshold number of segments for the relationship curve;

[0010] 3) When the duration of the permanent magnet synchronous motor vector control system in a stable operating condition is not less than the adaptive adjustment time threshold, the current loop feedforward parameters shall be adaptively adjusted according to the following steps:

[0011] 3-1) Determine the current direct-axis target current The current quadrature axis target current is located in the nth segment of the direct-axis current-inductance curve. It is located in the m-th segment of the quadrature-axis current-inductance relationship curve, where 1≤n≤N and 1≤m≤M;

[0012] 3-2) Based on the current direct-axis target current Cross-axis target current Calculate the current direct-axis target voltage quadrature axis target voltage

[0013] 3-3) Based on the current direct-axis target voltage quadrature axis target voltage Calculate the current direct-axis feedback current i d-n The corresponding theoretical value of direct-axis inductance and quadrature axis feedback current i q-m The corresponding theoretical value of quadrature axis inductance

[0014] 3-4) Calculate the percentage deviation of the direct-axis feedforward parameter for the nth segment of the direct-axis current-inductance relationship curve, and the percentage deviation of the quadrature-axis feedforward parameter for the mth segment of the quadrature-axis current-inductance relationship curve;

[0015] 3-5) Calculate the updated endpoint values ​​of each segment of the direct-axis current-inductance curve and the quadrature-axis current-inductance curve, replace the original endpoint values ​​of each segment of the current direct-axis current-inductance curve and the quadrature-axis current-inductance curve, and form the updated direct-axis current-inductance curve and the quadrature-axis current-inductance curve.

[0016] Preferably, the following steps are used to determine whether the permanent magnet synchronous motor vector control system is in a stable operating condition:

[0017] 2-1) Set the threshold ranges for motor speed, motor temperature, direct-axis feedback current change slope, quadrature-axis target current change slope, target torque change slope, and field weakening voltage margin.

[0018] 2-2) The permanent magnet synchronous motor vector control system is in a stable operating condition when the following conditions are met simultaneously;

[0019] If any of the following conditions are not met, then adaptive adjustment of the current loop feedforward parameters will no longer be performed:

[0020] ① The real-time motor speed is within the motor speed threshold range;

[0021] ② The real-time motor temperature is within the motor temperature threshold range;

[0022] ③ The slope of the real-time direct-axis feedback current change is within the threshold range of the slope of the direct-axis feedback current change;

[0023] ④ The slope of the real-time cross-axis target current change is within the threshold range of the slope of the cross-axis target current change;

[0024] ⑤ The real-time target torque change slope is within the target torque change slope threshold range;

[0025] ⑥ The real-time magnetic weakening voltage margin is not greater than the magnetic weakening voltage margin threshold.

[0026] Preferably, the direct-axis target voltage quadrature axis target voltage The calculation formula is as follows:

[0027]

[0028] In the formula, For the direct-axis target voltage, ω γ L represents the real-time speed of the motor. q-m For the current quadrature axis target current The quadrature-axis inductance corresponding to the quadrature-axis current-inductance relationship curve. The target current is the quadrature axis current;

[0029]

[0030] In the formula, Let ω be the quadrature-axis target voltage. γ L represents the real-time speed of the motor. d-n For the current direct-axis target current The corresponding direct-axis inductance on the direct-axis current-inductance curve. The target current is the direct axis current.

[0031] Preferably, the theoretical value of the direct-axis inductance Theoretical value of quadrature axis inductance The calculation formula is as follows:

[0032]

[0033] In the formula, For the direct-axis target voltage, ω γ This refers to the real-time speed of the motor. For the current quadrature axis feedback current i q-m The corresponding theoretical value of quadrature axis inductance, i q-m This is the quadrature axis feedback current;

[0034]

[0035] In the formula, Let ω be the quadrature-axis target voltage. γ This refers to the real-time speed of the motor. For the current direct-axis feedback current i d-n The corresponding theoretical value of direct-axis inductance, i d-n This is the direct-axis feedback current.

[0036] Preferably, the calculation formulas for the percentage deviation of the direct-axis feedforward parameter and the percentage deviation of the quadrature-axis feedforward parameter are as follows:

[0037]

[0038] In the formula, K d-n This represents the percentage deviation of the direct-axis feedforward parameters. For the current direct-axis feedback current i d-n The corresponding theoretical value of direct-axis inductance, L d-n For the current direct-axis target current The direct-axis inductance corresponding to the direct-axis current-inductance relationship curve;

[0039]

[0040] In the formula, K q-m This represents the percentage deviation of the cross-axis feedforward parameters. For the current quadrature axis feedback current i q-m The corresponding theoretical value of quadrature axis inductance, L q-m For the current quadrature axis target current The quadrature-axis inductance corresponding to the quadrature-axis current-inductance relationship curve.

[0041] Preferably, the endpoint update value is calculated according to the following formula:

[0042] ① The endpoint update value of the nth segment of the direct-axis current-inductance relationship curve is:

[0043]

[0044] In the formula, K′ d-n This represents the endpoint update value of the right endpoint of the nth segment of the direct-axis current-inductance relationship curve. K represents the original value of the right endpoint of the nth segment of the direct-axis current-inductance curve. d-n This represents the percentage deviation of the direct-axis feedforward parameter in the nth segment of the direct-axis current-inductance curve.

[0045] ② The updated value of the endpoint of the m-th segment of the quadrature-axis current-inductance relationship curve is:

[0046]

[0047] In the formula, K′ q-m This represents the endpoint update value of the right endpoint of the m-th segment of the quadrature-axis current-inductance curve. K represents the original value of the right endpoint of the m-th segment of the quadrature-axis current-inductance curve. q-m This represents the percentage deviation of the quadrature-axis feedforward parameter in the m-th segment of the quadrature-axis current-inductance curve.

[0048] Preferably, the percentage deviation of the direct-axis feedforward parameter and the percentage deviation of the quadrature-axis feedforward parameter are used for filtering before calculating the endpoint update value.

[0049] Preferably, the filtering process is mean filtering.

[0050] Preferably, each segment of the updated direct-axis current-inductance curve and quadrature-axis current-inductance curve is smoothed.

[0051] Preferably, the updated direct-axis current-inductance curve and quadrature-axis current-inductance curve are subjected to a rationality verification.

[0052] The advantages of this invention are as follows:

[0053] 1. This invention automatically identifies stable operating conditions and automatically acquires accurate feedforward parameter curves during motor operation. Compared with the traditional method of obtaining parameters through bench tests, this greatly improves the efficiency and accuracy of acquiring vector control current loop feedforward parameters.

[0054] 2. This invention can automatically adjust the feedforward parameters of the vector control current loop at all times, which can effectively avoid consistency problems caused by manufacturing errors and reliability problems caused by wear and aging throughout the entire life cycle, thereby improving the consistency, stability and reliability of the system.

[0055] 3. By accurately identifying the feedforward parameters of the vector control current loop, this invention increases the proportion of the feedforward parameters of the current loop and reduces the proportion of the closed-loop PI regulation, effectively avoiding overshoot or even oscillation caused by the closed-loop PI regulation, and improving the system responsiveness and stability. Attached Figure Description

[0056] Figure 1 This is a flowchart of the present invention;

[0057] Figure 2 This is a vector control block diagram according to an embodiment of the present invention. Detailed Implementation

[0058] like Figures 1 to 2 As shown, a method for adaptively adjusting the feedforward parameters of a permanent magnet synchronous motor vector control system includes the following steps:

[0059] 1) Set the adaptive adjustment time threshold and the threshold for the number of segments in the relationship curve;

[0060] 2) Divide the direct-axis current-inductance relationship curve into N segments and the quadrature-axis current-inductance relationship curve into M segments. Both N and M are not greater than the threshold number of segments of the relationship curve. In this embodiment, the direct-axis / current-inductance relationship curve is a curve in a two-dimensional coordinate system. Based on the current value on the x-axis in this two-dimensional coordinate system, the curve is divided into segments by range.

[0061] In this embodiment, the following steps are used to determine whether the permanent magnet synchronous motor vector control system is in a stable operating condition:

[0062] 2-1) Set the threshold ranges for motor speed, motor temperature, direct-axis feedback current change slope, quadrature-axis target current change slope, target torque change slope, and field weakening voltage margin.

[0063] 2-2) The permanent magnet synchronous motor vector control system is in a stable operating condition when the following conditions are met simultaneously;

[0064] If any of the following conditions are not met, then adaptive adjustment of the current loop feedforward parameters will no longer be performed:

[0065] ① The real-time motor speed is within the motor speed threshold range;

[0066] ② The real-time motor temperature is within the motor temperature threshold range;

[0067] ③ The slope of the real-time direct-axis feedback current change is within the threshold range of the slope of the direct-axis feedback current change;

[0068] ④ The slope of the real-time cross-axis target current change is within the threshold range of the slope of the cross-axis target current change;

[0069] ⑤ The real-time target torque change slope is within the target torque change slope threshold range;

[0070] ⑥ The real-time magnetic weakening voltage margin is not greater than the magnetic weakening voltage margin threshold.

[0071] 3) When the duration of the permanent magnet synchronous motor vector control system in a stable operating condition is not less than the adaptive adjustment time threshold, the current loop feedforward parameters shall be adaptively adjusted according to the following steps:

[0072] 3-1) Determine the current direct-axis target current The current quadrature axis target current is located in the nth segment of the direct-axis current-inductance curve. It is located in the m-th segment of the quadrature-axis current-inductance relationship curve, where 1≤n≤N and 1≤m≤M;

[0073] 3-2) Based on the current direct-axis target current Cross-axis target current Calculate the current direct-axis target voltage quadrature axis target voltage

[0074] The current loop feedforward parameter adjusted in this invention is the inductance value corresponding to the current in the direct-axis / quadrature-axis current-inductance relationship curve, and the relationship is shown below:

[0075]

[0076]

[0077] In the formula, Rs i d-n R s i q-m For direct-axis and quadrature-axis voltages, R s R is the equivalent resistance of the stator coil. Since this equivalent resistance is relatively small, s i d-n R s i q-m The value of can be ignored in the formula; while Both are rates of change of magnetic flux. Under steady-state conditions, the magnetic flux is stable, so this part in the formula is always 0. That is, when the permanent magnet synchronous motor vector control system is in a steady-state condition, the values ​​in the formula are all 0. All of these can be ignored; the direct-axis target voltage quadrature axis target voltage The calculation formula is as follows:

[0078]

[0079] In the formula, For the direct-axis target voltage, ω γ L represents the real-time speed of the motor. q-m For the current quadrature axis target current The quadrature-axis inductance corresponding to the quadrature-axis current-inductance relationship curve. The target current is the quadrature axis current;

[0080]

[0081] In the formula, Let ω be the quadrature-axis target voltage. γ L represents the real-time speed of the motor. d-n For the current direct-axis target current The corresponding direct-axis inductance on the direct-axis current-inductance curve. The target current is the direct axis current.

[0082] 3-3) Based on the current direct-axis target voltage quadrature axis target voltage Calculate the current direct-axis feedback current i d-n The corresponding theoretical value of direct-axis inductance and quadrature axis feedback current i q-m The corresponding theoretical value of quadrature axis inductance

[0083] The theoretical value of the direct-axis inductance Theoretical value of quadrature axis inductance The calculation formula is as follows:

[0084]

[0085] In the formula, For the direct-axis target voltage, ω γ This refers to the real-time speed of the motor. For the current quadrature axis feedback current i q-m The corresponding theoretical value of quadrature axis inductance, i q-m This is the quadrature axis feedback current;

[0086]

[0087] In the formula, Let ω be the quadrature-axis target voltage. γ This refers to the real-time speed of the motor. For the current direct-axis feedback current i d-n The corresponding theoretical value of direct-axis inductance, i d-n This is the direct-axis feedback current.

[0088] 3-4) Calculate the percentage deviation of the direct-axis feedforward parameter for the nth segment of the direct-axis current-inductance relationship curve, and the percentage deviation of the quadrature-axis feedforward parameter for the mth segment of the quadrature-axis current-inductance relationship curve;

[0089] The formulas for calculating the percentage deviation of the direct-axis feedforward parameter and the percentage deviation of the quadrature-axis feedforward parameter are as follows:

[0090]

[0091] In the formula, K d-n This represents the percentage deviation of the direct-axis feedforward parameters. For the current direct-axis feedback current i d-n The corresponding theoretical value of direct-axis inductance, L d-n For the current direct-axis target current The direct-axis inductance corresponding to the direct-axis current-inductance relationship curve;

[0092]

[0093] In the formula, K q-m This represents the percentage deviation of the cross-axis feedforward parameters. For the current quadrature axis feedback current i q-m The corresponding theoretical value of quadrature axis inductance, L q-m For the current quadrature axis target current The quadrature-axis inductance corresponding to the quadrature-axis current-inductance relationship curve.

[0094] In this embodiment, the percentage deviation of the direct-axis feedforward parameter and the percentage deviation of the quadrature-axis feedforward parameter are used for filtering before calculating the endpoint update value. The filtering method is mean filtering.

[0095] 3-5) Calculate the endpoint update values ​​of each segment of the direct-axis current-inductance curve and the quadrature-axis current-inductance curve, replace the original endpoint values ​​of each segment of the current direct-axis current-inductance curve and the quadrature-axis current-inductance curve, and form the updated direct-axis current-inductance curve and the quadrature-axis current-inductance curve. The update frequency and update ratio coefficient can be adjusted.

[0096] The endpoint update value and the endpoint original value are both inductance values ​​on the y-axis in the two-dimensional coordinate system. The horizontal coordinate of each data point on the updated direct axis / quadrature axis current-inductance relationship curve remains unchanged, that is, the current value remains unchanged, and only the inductance value of each data point is updated.

[0097] The update frequency refers to the frequency at which the direct-axis / quadrature-axis current-inductance relationship curves are updated. In this embodiment, the endpoint update values ​​are calculated 100 times, replacing the original endpoint values ​​once. The purpose is to ensure the accuracy of adjusting the feedforward parameters by reducing the update speed of the curves. The update ratio updates a portion of the direct-axis / quadrature-axis current-inductance relationship curves, aiming to ensure the accuracy of adjusting the feedforward parameters by reducing the update step size. In summary, the entire process of adaptively adjusting the feedforward parameters of the permanent magnet synchronous motor vector control system is a slow process, prioritizing stability over speed. The stability and accuracy of the adaptive adjustment process are ensured through the update frequency and update ratio.

[0098] The updated direct-axis current-inductance curves and quadrature-axis current-inductance curves can be used to obtain the inductance value corresponding to the current target current, which is the feedforward parameter of the current loop, for use in current loop control.

[0099] In this embodiment, the endpoint update value is calculated according to the following formula:

[0100] ① The endpoint update value of the nth segment of the direct-axis current-inductance relationship curve is:

[0101]

[0102] In the formula, K′ d-n This represents the endpoint update value of the right endpoint of the nth segment of the direct-axis current-inductance relationship curve. K represents the original value of the right endpoint of the nth segment of the direct-axis current-inductance curve. d-n This represents the percentage deviation of the direct-axis feedforward parameter in the nth segment of the direct-axis current-inductance curve.

[0103] ② The updated value of the endpoint of the m-th segment of the quadrature-axis current-inductance relationship curve is:

[0104]

[0105] In the formula, K′ q-mThis represents the endpoint update value of the right endpoint of the m-th segment of the quadrature-axis current-inductance curve. K represents the original value of the right endpoint of the m-th segment of the quadrature-axis current-inductance curve. g-m This represents the percentage deviation of the quadrature-axis feedforward parameter in the m-th segment of the quadrature-axis current-inductance curve.

[0106] The updated direct-axis current-inductance curve and quadrature-axis current-inductance curve are smoothed.

[0107] The updated direct-axis / quadrature-axis current-inductance relationship curves are validated for rationality, that is, the monotonicity and amplitude range of each segment of the curve are judged for rationality.

[0108] The range of values ​​for each data point on the direct-axis / quadrature-axis current-inductance relationship curve is determined by the hardware design characteristics (i.e., provided by the manufacturer) to prevent the updating of incorrectly calculated endpoint values, which could affect the stability and responsiveness of the entire system.

[0109] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications made to the present invention by those skilled in the art without departing from the spirit of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method for self-adapting feedforward parameters of a vector control system of a permanent magnet synchronous motor, characterized in that, Includes the following steps: 1) Set the adaptive adjustment time threshold and the threshold for the number of segments in the relationship curve; 2) Divide the direct-axis current-inductance curve into N segments, and the quadrature-axis current-inductance curve into... For each segment, N and M are not greater than the threshold number of segments in the relationship curve; 3) When the duration of the permanent magnet synchronous motor vector control system in a stable operating condition is not less than the adaptive adjustment time threshold, the current loop feedforward parameters shall be adaptively adjusted according to the following steps: 3-1) Determine the current direct-axis target current Located on the direct-axis current-inductance curve Segment, current cross-axis target current Located on the quadrature axis current-inductance curve Segment, where 1≤ ≤ ,1≤ ≤ ; 3-2) Based on the current direct-axis target current Cross-axis target current Calculate the current direct-axis target voltage. Cross-axis target voltage ; 3-3) Based on the current direct-axis target voltage Cross-axis target voltage Calculate the current direct-axis feedback current. The corresponding theoretical value of direct-axis inductance and quadrature axis feedback current The corresponding theoretical value of quadrature axis inductance ; 3-4) Calculate the direct-axis current-inductance relationship curve. The percentage deviation of the direct-axis feedforward parameters in the segment, and the quadrature-axis current-inductance relationship curve. The percentage deviation of the cross-axis feedforward parameter is calculated using the following formulas: ； In the formula, This represents the percentage deviation of the direct-axis feedforward parameters. For the current direct-axis feedback current The corresponding theoretical value of direct-axis inductance, For the current direct-axis target current The direct-axis inductance corresponding to the direct-axis current-inductance relationship curve; ； In the formula, This represents the percentage deviation of the cross-axis feedforward parameters. For the current quadrature axis feedback current The corresponding theoretical value of quadrature axis inductance, For the current quadrature axis target current The quadrature-axis inductance corresponding to the quadrature-axis current-inductance relationship curve; 3-5) Calculate the updated endpoint values ​​of each segment of the direct-axis current-inductance curve and the quadrature-axis current-inductance curve, and replace the original endpoint values ​​of each segment of the current direct-axis current-inductance curve and the quadrature-axis current-inductance curve to form updated direct-axis current-inductance curves and quadrature-axis current-inductance curves. The updated endpoint values ​​are calculated according to the following formula: ① Direct-axis current-inductance relationship curve The endpoint update value of the segment is: ； In the formula, The first direct-axis current-inductance curve The endpoint update value of the right endpoint of the segment. The first direct-axis current-inductance curve The original value of the right endpoint of the segment. The first direct-axis current-inductance curve The percentage deviation of the direct-axis feedforward parameter of the segment; ② The quadrature-axis current-inductance relationship curve The endpoint update value of the segment is: ； In the formula, The quadrature axis current-inductance relationship curve is the first one. The endpoint update value of the right endpoint of the segment. The quadrature axis current-inductance relationship curve is the first one. The original value of the right endpoint of the segment. The quadrature axis current-inductance relationship curve is the first one. The percentage deviation of the cross-axis feedforward parameter of the segment.

2. The method for adaptively adjusting the feedforward parameters of the vector control system for a permanent magnet synchronous motor according to claim 1, characterized in that, Determine whether the permanent magnet synchronous motor vector control system is in a stable operating condition by following these steps: 2-1) Set the threshold ranges for motor speed, motor temperature, direct-axis feedback current change slope, quadrature-axis target current change slope, target torque change slope, and field weakening voltage margin. 2-2) The permanent magnet synchronous motor vector control system is in a stable operating condition when the following conditions are met simultaneously; If any of the following conditions are not met, then adaptive adjustment of the current loop feedforward parameters will no longer be performed: ① The real-time motor speed is within the motor speed threshold range; ② The real-time motor temperature is within the motor temperature threshold range; ③ The slope of the real-time direct-axis feedback current change is within the threshold range of the slope of the direct-axis feedback current change; ④ The slope of the real-time cross-axis target current change is within the threshold range of the slope of the cross-axis target current change; ⑤ The slope of the real-time target torque change is within the threshold range of the target torque change slope; ⑥ The real-time magnetic weakening voltage margin is not greater than the magnetic weakening voltage margin threshold.

3. The method for adaptively adjusting the feedforward parameters of the vector control system for a permanent magnet synchronous motor according to claim 1, characterized in that, The direct-axis target voltage Cross-axis target voltage The calculation formula is as follows: ； In the formula, The target voltage is the direct axis. This refers to the real-time speed of the motor. For the current quadrature axis target current The quadrature-axis inductance corresponding to the quadrature-axis current-inductance relationship curve. The target current is the quadrature axis current; ； In the formula, The target voltage is the quadrature axis. This refers to the real-time speed of the motor. For the current direct-axis target current The corresponding direct-axis inductance on the direct-axis current-inductance curve. The target current is the direct axis current.

4. The method for adaptively adjusting the feedforward parameters of the vector control system for a permanent magnet synchronous motor according to claim 1, characterized in that, The theoretical value of the direct-axis inductance Theoretical value of quadrature axis inductance The calculation formula is as follows: ； In the formula, The target voltage is the direct axis. This refers to the real-time speed of the motor. For the current quadrature axis feedback current The corresponding theoretical value of quadrature axis inductance, This is the quadrature axis feedback current; ； In the formula, The target voltage is the quadrature axis. This refers to the real-time speed of the motor. For the current direct-axis feedback current The corresponding theoretical value of direct-axis inductance, This is the direct-axis feedback current.

5. The method for adaptively adjusting the feedforward parameters of the vector control system for a permanent magnet synchronous motor according to claim 1, characterized in that, The percentage deviations of the direct-axis feedforward parameters and the percentage deviations of the quadrature-axis feedforward parameters are filtered before being used to calculate the endpoint update values.

6. The method for adaptively adjusting the feedforward parameters of the vector control system for a permanent magnet synchronous motor according to claim 5, characterized in that, The filtering method is mean filtering.

7. The method for adaptively adjusting the feedforward parameters of the vector control system for a permanent magnet synchronous motor according to claim 1, characterized in that, The updated direct-axis current-inductance curve and quadrature-axis current-inductance curve are smoothed.

8. The method for adaptively adjusting the feedforward parameters of the vector control system for a permanent magnet synchronous motor according to claim 1, characterized in that, The updated direct-axis current-inductance curve and quadrature-axis current-inductance curve are verified for rationality.

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