A torque ripple suppression method and system for an electric drive axle based on active disturbance rejection control

Abstract

The application relates to the technical field of electromechanical control, and discloses a torque ripple suppression method and system for an electric drive axle based on active disturbance rejection control. The method comprises the following steps: obtaining three-phase currents, a motor speed and a target torque value of the electric drive axle; transforming the three-phase currents to obtain a cross-axis current feedback of the electric drive axle; performing frequency band separation on the cross-axis current feedback by taking a mechanical cutoff frequency corresponding to the motor speed and an electrical harmonic frequency as filter parameters to obtain disturbance observation values; performing weighted summation on compensation values of the mechanical disturbance observation values and compensation values of the electrical harmonic observation values to obtain a comprehensive feedforward compensation value; scaling a motor torque constant based on the target torque value to obtain a cross-axis current reference value; and performing space vector modulation on the comprehensive feedforward compensation value and the cross-axis current reference value to obtain a switching control sequence of the electric drive axle. The application can improve the precision of torque ripple suppression for an electric drive axle based on active disturbance rejection control.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electromechanical control, and in particular to a torque ripple suppression method and system for an electric drive axle based on active disturbance rejection control. BACKGROUND

[0002] Torque ripple is a key problem affecting the smoothness and control accuracy of the electric drive axle, which is caused by the combined action of external mechanical disturbance and internal electrical disturbance. The external mechanical disturbance is closely related to dynamic parameters such as motor speed and transmission inertia, while the internal electrical disturbance is caused by factors such as power supply harmonics and inverter switching characteristics. The frequency characteristics and influence mechanisms of the two types of disturbances are significantly different, and it is difficult to effectively suppress them by a single control method. Existing technologies often fail to accurately separate and address the two types of disturbances, and only use fixed parameter control strategies, which cannot dynamically adapt to changes in the operating state of the electric drive axle, resulting in insufficient accuracy of disturbance observation and difficulty in fully capturing the true characteristics of various disturbances.

[0003] Existing torque ripple suppression methods generally have the problems of weak compensation pertinence and dynamic response lag, and cannot adjust the compensation amplitude according to the dynamic changes of mechanical disturbance, nor can they accurately offset the phase deviation of electrical harmonic disturbance, so that the compensation amount does not match the actual disturbance. At the same time, the calculation of the quadrature axis current reference value in the traditional method does not fully consider the change trend of the target torque, and the motor torque constant is often a fixed value, resulting in a deviation between the current control reference and the actual torque demand, which further affects the torque ripple suppression effect. These defects cause the electric drive axle to still have obvious torque fluctuations under different operating conditions, which not only reduces the stability and reliability of the equipment operation, but also may exacerbate mechanical wear and increase energy consumption, and cannot meet the application requirements of high precision and high smoothness. SUMMARY

[0004] The present application provides a torque ripple suppression method and system for an electric drive axle based on active disturbance rejection control, which mainly aims to solve the problem of low precision in torque ripple suppression for an electric drive axle based on active disturbance rejection control.

[0005] To achieve the above purpose, the present application provides a torque ripple suppression method for an electric drive axle based on active disturbance rejection control, which comprises:

[0006] Obtaining three-phase current, motor speed and target torque value in the electric drive axle;

[0007] Performing coordinate transformation on the three-phase current to obtain the quadrature axis current feedback of the electric drive axle;

[0008] respectively, the mechanical cutoff frequency corresponding to the motor speed and the electrical harmonic frequency as the filtering parameters, the quadrature axis current feedback quantity is band-separated to obtain the external mechanical disturbance observation value and the internal electrical disturbance observation value of the electric drive axle;

[0009] The compensation quantity of the mechanical disturbance observation value and the compensation quantity of the electrical harmonic observation value are weighted and summed to obtain the comprehensive feedforward compensation quantity of the electric drive axle;

[0010] The motor torque constant of the electric drive axle is scaled based on the target torque value to obtain the quadrature axis current reference value of the electric drive axle;

[0011] The comprehensive feedforward compensation quantity and the quadrature axis current reference value are space vector modulated to obtain the switching control sequence of the electric drive axle.

[0012] In a preferred embodiment, the three-phase current in the electric drive axle, the motor speed and the target torque value are obtained, comprising:

[0013] The phase winding current in the electric drive axle is analog-digital converted to obtain the three-phase current of the electric drive axle;

[0014] The motor sensor signal in the electric drive axle is analyzed to obtain the motor speed of the electric drive axle;

[0015] The torque instruction value of the internal register in the electric drive axle is read through the data interface of the motor controller to obtain the target torque value of the electric drive axle.

[0016] In a preferred embodiment, the three-phase current is coordinate-transformed to obtain the quadrature axis current feedback quantity of the electric drive axle, comprising:

[0017] The three-phase current is Clark-transformed to obtain the current component of the electric drive axle;

[0018] The current component is Park-transformed to obtain the quadrature axis current feedback quantity of the electric drive axle.

[0019] In a preferred embodiment, the quadrature axis current feedback quantity is band-separated to obtain the external mechanical disturbance observation value and the internal electrical disturbance observation value of the electric drive axle, respectively, the mechanical cutoff frequency corresponding to the motor speed and the electrical harmonic frequency as the filtering parameters, comprising:

[0020] The mechanical cutoff frequency of the electric drive axle is calculated based on the motor speed and the transmission inertia of the electric drive axle;

[0021] The product value of the power supply fundamental frequency of the electric drive axle and the target electrical harmonic number of the electric drive axle is taken as the electrical harmonic frequency of the electric drive axle.

[0022] The cross-axis current feedback quantity is low-pass filtered using the mechanical cutoff frequency as the threshold frequency to obtain the external mechanical disturbance observation value of the electric drive bridge;

[0023] By bandpass filtering the quadrature-axis current feedback quantity with the electrical harmonic frequency as the center frequency, the internal electrical disturbance observation value of the electric drive bridge is obtained.

[0024] In a preferred embodiment, calculating the mechanical cutoff frequency of the electric drive axle based on the motor speed and the transmission inertia of the electric drive axle includes:

[0025] The ratio of the motor speed to the transmission inertia is used as the instantaneous acceleration characteristic of the electric drive axle;

[0026] Based on the transmission inertia, the instantaneous acceleration characteristic is dynamically compensated to obtain the mechanical cutoff frequency of the electric drive axle.

[0027] In a preferred embodiment, the step of weighted summing of the compensation amount of the mechanical disturbance observation and the compensation amount of the electrical harmonic observation to obtain the comprehensive feedforward compensation amount of the electric drive bridge includes:

[0028] The feedforward gain of the observed mechanical disturbance is adjusted to obtain the first feedforward compensation component of the electric drive bridge;

[0029] The electrical harmonic disturbance observations are phase-advanced to obtain the second feedforward compensation component of the electric drive bridge;

[0030] The first feedforward compensation component and the second feedforward compensation component are vector-superimposed to obtain the comprehensive feedforward compensation amount of the electric drive bridge.

[0031] In a preferred embodiment, the formula for calculating the integrated feedforward compensation includes:

[0032]

[0033] in, This is the comprehensive feedforward compensation amount. This is the first feedforward compensation component. The observed values ​​of the mechanical disturbance are... This is the second feedforward compensation component. The electrical harmonic disturbance observation value, The differential time constant is The change in the observed internal electrical disturbance is the amount of change. This represents the sampling time interval.

[0034] In a preferred embodiment, scaling the motor torque constant of the electric drive axle based on the target torque value to obtain the quadrature-axis current reference value of the electric drive axle includes:

[0035] The scaling factor of the electric drive axle is determined based on the changing trend of the target torque value;

[0036] The product of the motor torque constant and the scaling factor is taken as the equivalent motor torque constant of the electric drive bridge.

[0037] The quotient of the target torque value and the equivalent motor torque constant is used as the reference value of the quadrature-axis current of the electric drive bridge.

[0038] In a preferred embodiment, the step of performing space vector modulation on the integrated feedforward compensation and the quadrature-axis current reference value to obtain the switching control sequence of the electric drive bridge includes:

[0039] The current error of the electric drive bridge is obtained by subtracting the cross-axis current reference value from the cross-axis current feedback value.

[0040] The current error is integrally adjusted to obtain the first voltage command component of the electric drive bridge;

[0041] By integrating the first voltage command component with the comprehensive feedforward compensation, the switching control sequence of the electric drive bridge is obtained.

[0042] To address the aforementioned problems, the present invention also provides an electric drive bridge torque ripple suppression system based on active disturbance rejection control, the system comprising:

[0043] The data acquisition module acquires the three-phase current, motor speed, and target torque value from the electric drive axle.

[0044] The quadrature-axis current feedback module performs coordinate transformation on the three-phase current to obtain the quadrature-axis current feedback of the electric drive bridge;

[0045] The disturbance observation module uses the mechanical cutoff frequency and electrical harmonic frequency corresponding to the motor speed as filtering parameters to perform frequency band separation on the quadrature axis current feedback, thereby obtaining the external mechanical disturbance observation value and the internal electrical disturbance observation value of the electric drive bridge.

[0046] The integrated feedforward compensation module weights and sums the compensation amounts of the mechanical disturbance observations and the electrical harmonic observations to obtain the integrated feedforward compensation amount of the electric drive bridge.

[0047] The quadrature axis current reference value module scales the motor torque constant of the electric drive bridge based on the target torque value to obtain the quadrature axis current reference value of the electric drive bridge;

[0048] The switching control sequence module performs space vector modulation on the integrated feedforward compensation amount and the quadrature axis current reference value to obtain the switching control sequence of the electric drive bridge.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] 1. This invention accurately acquires the three-phase current, motor speed, and target torque value of the electric drive axle. Through Clarke and Parker transforms, it obtains a precise quadrature-axis current feedback. Using the mechanical cutoff frequency and electrical harmonic frequency corresponding to the motor speed as filtering parameters, it achieves precise separation of external mechanical disturbance observations and internal electrical disturbance observations, ensuring comprehensive and accurate identification of both types of disturbances. A comprehensive feedforward compensation is formed through feedforward gain adjustment, phase lead correction, and vector superposition. Simultaneously, a suitable quadrature-axis current reference value is obtained by dynamically scaling the motor torque constant based on the target torque value. This ensures that the compensation strategy and current control benchmark accurately match the system operating state, significantly improving the targeting and accuracy of torque ripple suppression and resulting in smoother torque output from the electric drive axle.

[0051] 2. This invention generates a switching control sequence by integrating the feedforward compensation and the quadrature-axis current reference value through space vector modulation. It combines the disturbance prediction and suppression capabilities of feedforward compensation with the deviation correction capabilities of current closed-loop regulation, thus both proactively offsetting various disturbances and correcting current deviations in real time, significantly improving control response speed and stability. Dynamically adaptable mechanical cutoff frequency, flexibly adjustable scaling factor, and precise phase correction enable the system to respond to changes in operating status in real time, effectively enhancing the adaptability of the electric drive axle under different operating conditions, reducing mechanical wear and energy consumption caused by torque pulsation, extending equipment lifespan, and simultaneously improving the dynamic response capability and steady-state accuracy of torque control to meet high-precision drive requirements. Attached Figure Description

[0052] Figure 1 This is a flowchart illustrating a method for suppressing torque ripple in an electric drive bridge based on active disturbance rejection control, as provided in an embodiment of the present invention.

[0053] Figure 2 A functional block diagram of an electric drive bridge torque ripple suppression system based on active disturbance rejection control is provided in an embodiment of the present invention.

[0054] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0055] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0056] This application provides a method for suppressing torque ripple in an electric drive axle based on active disturbance rejection control (ADRC). The execution entity of this method includes, but is not limited to, at least one of the following electronic devices that can be configured to execute the method provided in this application: a server, a terminal, etc. In other words, the method can be executed by software or hardware installed on a terminal device or a server device. The server includes, but is not limited to, a single server, a server cluster, a cloud server, or a cloud server cluster. The server can be an independent server or a cloud server providing basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, content delivery networks (CDNs), and big data and artificial intelligence platforms.

[0057] Reference Figure 1 The diagram shown is a flowchart illustrating a method for suppressing torque ripple in an electric drive bridge based on active disturbance rejection control (ADRC) according to an embodiment of the present invention. In this embodiment, the method for suppressing torque ripple in an electric drive bridge based on ADRC includes:

[0058] In this embodiment of the invention, the acquisition of the three-phase current, motor speed, and target torque value in the electric drive bridge is specifically used for:

[0059] The phase winding currents in the electric drive bridge are converted from analog to digital to obtain the three-phase currents of the electric drive bridge.

[0060] The motor speed of the electric drive bridge is obtained by analyzing the motor sensing signal in the electric drive bridge.

[0061] The torque command value of the electric drive bridge is obtained by reading the internal register of the electric drive bridge through the data interface of the motor controller.

[0062] Specifically, a high-precision analog signal acquisition circuit is used to connect to the current output terminal of the phase winding to directly acquire the continuously changing analog current signal flowing in the phase winding. This analog signal can truly reflect the real-time current change state of the phase winding.

[0063] Specifically, a speed sensing device that matches the electric drive axle motor is selected and installed at the end of the motor shaft to ensure that the sensing device can sense the rotation state of the shaft in real time. The sensing device will generate a corresponding motor sensing signal according to the rotation of the shaft. The form of the signal is compatible with the type of sensing device, and the signal parameters will change synchronously with the change of the shaft speed.

[0064] Specifically, a stable communication connection is established between the motor controller's data interface and the electric drive axle's internal register using a standard communication interface line. The motor controller sends a data read command to the electric drive axle's internal register through the data interface. This command is written according to a preset communication format and explicitly points to the register address storing the torque command value.

[0065] Furthermore, the acquired analog current signal is transmitted to the signal input terminal of the analog-to-digital converter chip. The analog-to-digital converter chip continuously samples the analog current signal at a fixed frequency through its internal signal sampling circuit, converting the analog current signal at each sampling moment into a corresponding digital quantity. During the conversion process, the chip's internal reference voltage calibration mechanism ensures the accurate correspondence between the digital quantity and the analog current signal. Finally, it outputs three sets of digital current signals corresponding to the three-phase windings of the electric drive bridge. These three sets of digital current signals are the three-phase currents of the electric drive bridge.

[0066] Furthermore, the motor sensing signal output by the sensing device is connected to the signal analysis circuit. The circuit first filters the signal to remove electromagnetic interference and environmental noise. Then, the weak sensing signal is amplified to a suitable amplitude for analysis by the signal amplification circuit. Next, the signal recognition circuit extracts the speed-related feature information in the signal, such as the pulse frequency and period of the signal. Through continuous monitoring and analysis of these feature information, the rotational speed of the motor shaft is accurately determined. Finally, based on the fixed correspondence between the feature information and the rotational speed, a physical quantity that clearly reflects the real-time rotational speed of the motor is directly output. This physical quantity is the motor speed of the electric drive axle.

[0067] Furthermore, after receiving the read command, the internal register of the electric drive axle calls its own storage read unit to extract the pre-stored torque command value data from the specified storage address. This data is related to the torque control command required for motor operation. Subsequently, the extracted torque command value data is fed back to the motor controller through the communication connection line. After the motor controller receives and confirms that the data is correct, the data is the target torque value of the electric drive axle.

[0068] In summary, by directly capturing the original current signal of the phase winding through high-precision analog-to-digital conversion technology, the continuously changing analog current signal is converted into a digital signal, effectively preserving the true characteristics and details of the current signal, avoiding distortion and interference during signal transmission, and providing accurate and reliable raw data support for subsequent control links such as coordinate transformation and disturbance observation. This ensures that the entire torque ripple suppression control logic is based on the real current operating state, thereby improving the accuracy and effectiveness of the control strategy from the source.

[0069] In summary, by filtering, amplifying, and extracting features from the motor sensor signals, the rotational state of the motor shaft can be accurately identified, and real-time speed data reflecting the actual operating speed of the motor can be output. This data not only provides a key basis for calculating the mechanical cutoff frequency, but also dynamically feeds back the operating conditions of the electric drive axle, enabling the control strategy to be adjusted in real time according to speed changes, enhancing the dynamic response capability of the control, and avoiding problems such as inaccurate disturbance observation and compensation calculation deviation caused by speed detection errors, thus ensuring the stability of torque pulsation suppression effect.

[0070] In summary, by using a standard data interface to enable direct communication between the motor controller and the internal registers of the electric drive axle, the preset torque command value can be obtained quickly and accurately. This avoids the delays and errors caused by indirect signal conversion, ensuring the real-time performance and accuracy of the target torque value. It provides a clear control objective for subsequent motor torque constant scaling and quadrature axis current reference value calculation, allowing the entire control strategy to be precisely implemented around the preset torque requirement. At the same time, this reading method complies with industrial communication standards and motor control interface design specifications, improving the system's compatibility and reliability.

[0071] In this embodiment of the invention, when performing coordinate transformation on the three-phase current to obtain the quadrature-axis current feedback of the electric drive bridge, it is specifically used for:

[0072] The three-phase current is subjected to Clarke transformation to obtain the current component of the electric drive bridge;

[0073] The current component is subjected to Parker transformation to obtain the quadrature-axis current feedback of the electric drive bridge.

[0074] Specifically, the three-phase current of the electric drive bridge is connected to a dedicated signal processing circuit. This circuit first performs anti-interference processing on the three-phase current signal, and removes electromagnetic interference and high-frequency noise mixed in the signal through a shielded filter component to ensure the purity of the current signal.

[0075] Specifically, the current position of the motor rotor is acquired in real time through a position sensing module, thereby determining the spatial phase of the rotor magnetic field. During the Park transformation, the current components in the two-phase stationary coordinate system are subjected to a rotating coordinate transformation based on the spatial phase of the rotor magnetic field.

[0076] Furthermore, the time-domain signals corresponding to the three-phase currents are mapped to a two-phase stationary coordinate system. During the mapping process, based on the phase distribution relationship of the three-phase currents in space, the signal synthesis unit inside the circuit performs vector decomposition and recombination of the three-phase current signals, converting the originally independent three-phase current signals into two orthogonal current signals in the two-phase stationary coordinate system. These two orthogonal current signals are the current components of the electric drive bridge.

[0077] Furthermore, the phase of the current component is kept synchronized with the phase of the rotor magnetic field through the phase adjustment circuit inside the unit, realizing the transformation from a two-phase stationary coordinate system to a two-phase rotating coordinate system. The transformed current component is decomposed into two current signals along the rotor magnetic field direction and perpendicular to the rotor magnetic field direction. The current signal perpendicular to the rotor magnetic field direction is the quadrature axis current feedback quantity of the electric drive bridge.

[0078] In summary, the Clarke transform converts the originally independent three-phase current signals with phase differences into orthogonal current components in a two-phase stationary coordinate system. This simplifies the dimensions of the current signal, eliminates the coupling between the three-phase currents, and makes subsequent processing of the current signal more convenient and efficient. The transformation process fully preserves the amplitude and phase information of the original three-phase currents, ensuring that the current components accurately reflect the current operating state of the electric drive bridge, and providing a standardized and easily processed signal foundation for subsequent Park transforms.

[0079] In summary, the Parker transform uses the rotor magnetic field phase as a reference to convert the current components in a two-phase stationary coordinate system into signals in a two-phase rotating coordinate system. This synchronizes the current signal with the rotor magnetic field, directly separating the quadrature-axis current feedback quantity, which is closely related to the motor torque output. This transformation achieves a precise correlation between the current signal and the motor's mechanical motion state, allowing the quadrature-axis current feedback quantity to directly reflect the core current components affecting torque output. This provides targeted and physically meaningful feedback data for subsequent disturbance observation and compensation calculation.

[0080] In this embodiment of the invention, when the frequency band separation of the quadrature-axis current feedback quantity is performed using the mechanical cutoff frequency and electrical harmonic frequency corresponding to the motor speed as filtering parameters to obtain the external mechanical disturbance observation value and internal electrical disturbance observation value of the electric drive bridge, it is specifically used for:

[0081] The mechanical cutoff frequency of the electric drive axle is calculated based on the motor speed and the transmission inertia of the electric drive axle.

[0082] The product of the power supply fundamental frequency of the electric drive bridge and the target electrical harmonic order of the electric drive bridge is taken as the electrical harmonic frequency of the electric drive bridge.

[0083] The cross-axis current feedback quantity is low-pass filtered using the mechanical cutoff frequency as the threshold frequency to obtain the external mechanical disturbance observation value of the electric drive bridge;

[0084] By bandpass filtering the quadrature-axis current feedback quantity with the electrical harmonic frequency as the center frequency, the internal electrical disturbance observation value of the electric drive bridge is obtained.

[0085] Specifically, the motor speed signal and transmission inertia-related parameters of the electric drive axle are input. A dedicated data acquisition circuit captures the motor speed signal in real time, ensuring that the acquired speed data accurately reflects the motor's current rotational state. Simultaneously, the transmission inertia parameters are input to the processing unit in a fixed data format. The processing unit first performs dynamic analysis on the motor speed data, capturing changes in speed over time.

[0086] Specifically, the fundamental frequency of the power supply and the target electrical harmonic number are pre-defined and stored through the system parameter configuration unit of the electric drive bridge. The fundamental frequency of the power supply is the basic frequency of the power supply when the electric drive bridge is running normally, and the target electrical harmonic number is a specific harmonic number pre-set according to the system suppression requirements.

[0087] Specifically, the quadrature-axis current feedback is transmitted to the low-pass filter circuit, and the calculated mechanical cutoff frequency is input as the threshold frequency to the parameter configuration terminal of the filter circuit to clarify the frequency selection criteria of the filter circuit.

[0088] Specifically, the quadrature axis current feedback is connected to the bandpass filter processing unit, and the calculated electrical harmonic frequency is used as the center frequency input to the frequency setting module of the bandpass filter unit. At the same time, a reasonable passband width is preset according to the characteristics of the electrical harmonics to ensure that the filter unit can accurately capture signals near the target frequency.

[0089] Furthermore, by combining pre-stored transmission inertia information and using internal numerical calculation logic, the motor speed and transmission inertia are correlated and calculated to obtain an instantaneous acceleration characteristic quantity that can characterize the changes in the motor's motion state. Subsequently, based on the physical characteristics of transmission inertia, the obtained instantaneous acceleration characteristic quantity is dynamically compensated and adjusted. During the compensation process, the influence of transmission inertia on the motor's motion response is fully considered. Through continuous optimization and adjustment, a physical quantity that can accurately define the frequency range of mechanical disturbances is finally obtained. This physical quantity is the mechanical cutoff frequency of the electric drive axle.

[0090] Furthermore, the data retrieval module extracts the preset power supply fundamental frequency and the value corresponding to the target electrical harmonic order from the storage unit, and inputs these two values ​​into the multiplication unit. The multiplication unit performs product calculation on the two values ​​according to a fixed calculation logic. During the calculation process, a numerical verification mechanism is used to ensure the accuracy of the calculation result and avoid the subsequent filtering effect being affected by numerical errors. The final product result is the electrical harmonic frequency of the electric drive bridge.

[0091] Furthermore, after the low-pass filter circuit starts working, it performs frequency analysis on the input quadrature-axis current feedback quantity, identifies various frequency components contained in the current feedback quantity one by one, retains the signal components in the quadrature-axis current feedback quantity with frequencies lower than the threshold according to the set mechanical cutoff frequency threshold, and filters out all signal components with frequencies higher than the threshold. These retained low-frequency signal components mainly correspond to the external mechanical disturbances affected by the electric drive bridge during operation. The signal output after filtering is the external mechanical disturbance observation value of the electric drive bridge.

[0092] Furthermore, the bandpass filter unit performs a comprehensive frequency scan and analysis of the quadrature axis current feedback quantity, accurately identifies the signal components in the current feedback quantity that are consistent with the electrical harmonic frequency and within the passband width, retains these signal components completely, and thoroughly filters out other signal components whose frequencies exceed the passband range. The retained signal components correspond to the harmonic disturbances generated by the internal electrical system of the electric drive bridge. The signal output after bandpass filtering is the observed value of the internal electrical disturbance of the electric drive bridge.

[0093] In summary, by fully integrating the dynamic operating parameters and inherent mechanical characteristics of the electric drive bridge, the calculated mechanical cutoff frequency can accurately match the real-time operating state of the electric drive bridge, avoiding the insufficient adaptability problem caused by fixed frequency thresholds. This mechanical cutoff frequency can accurately define the frequency range corresponding to external mechanical disturbances, providing a scientific and dynamic threshold basis for subsequent low-pass filtering, ensuring the effective separation of external mechanical disturbances from other frequency components. This meets the core requirement of accurate identification of external disturbances in active disturbance rejection control, improves the pertinence and accuracy of disturbance observation, and lays a reliable foundation for subsequent compensation control.

[0094] In summary, by employing explicit frequency synthesis logic, this method directly identifies the core frequency of internal electrical harmonics related to torque ripple. This frequency accurately corresponds to specific subharmonic disturbances generated by the internal electrical system of the electric drive axle, avoiding the blindness of harmonic frequency identification. Compared to generalized harmonic detection methods, this approach focuses on target harmonic components, providing precise center frequency parameters for bandpass filtering. This ensures that subsequent filtering processes can efficiently capture internal electrical disturbance signals, while simplifying the frequency calculation process and improving the real-time performance of the control strategy, thus meeting the technical requirements of rapid internal disturbance location in active disturbance rejection control.

[0095] In summary, by utilizing the frequency filtering characteristics of low-pass filters and based on the precisely calculated mechanical cutoff frequency, the low-frequency signal components corresponding to external mechanical disturbances in the quadrature-axis current feedback can be efficiently retained, while high-frequency interference signals are completely filtered out, achieving precise separation of external mechanical disturbances from other frequency components. This observation accurately reflects the impact of external mechanical load fluctuations and transmission system friction on the electric drive bridge current, providing clean and effective data support for subsequent mechanical disturbance compensation. It avoids compensation deviations caused by noise signals and enhances the torque ripple suppression strategy's ability to suppress external mechanical disturbances.

[0096] In summary, bandpass filtering can accurately capture specific frequency band signals centered on electrical harmonic frequencies in the quadrature-axis current feedback, efficiently filtering out the fundamental signal, other irrelevant harmonics, and noise interference, thus achieving accurate extraction of internal electrical disturbance signals. This observation accurately reflects disturbances caused by electrical factors such as inverter switching harmonics and winding electromagnetic coupling within the electric drive axle, providing targeted and highly accurate feedback data for subsequent electrical harmonic disturbance compensation. This enables the compensation strategy to accurately offset the impact of internal electrical disturbances on torque output, significantly improving the comprehensiveness and effectiveness of torque ripple suppression and ensuring the stability and smoothness of the electric drive axle operation.

[0097] In this embodiment of the invention, the calculation of the mechanical cutoff frequency of the electric drive axle based on the motor speed and the transmission inertia of the electric drive axle is specifically used for:

[0098] The ratio of the motor speed to the transmission inertia is used as the instantaneous acceleration characteristic of the electric drive axle;

[0099] Based on the transmission inertia, the instantaneous acceleration characteristic is dynamically compensated to obtain the mechanical cutoff frequency of the electric drive axle.

[0100] Specifically, the speed acquisition unit captures the motor speed signal of the electric drive axle in real time. This signal reflects the speed of the motor rotation in a continuously changing form. At the same time, the parameter storage module retrieves the pre-recorded transmission inertia information of the electric drive axle. The transmission inertia information is a fixed parameter that characterizes the magnitude of the inertia of the electric drive axle mechanical system, ensuring that the data formats of both are consistent and can be directly used for subsequent processing.

[0101] Specifically, the obtained instantaneous acceleration characteristic is transmitted to the dynamic compensation processing unit, and the transmission inertia parameters of the electric drive axle are retrieved again and input into the unit. The compensation unit has a pre-built compensation logic based on the transmission inertia characteristics, which can adjust the compensation amplitude according to the magnitude of the transmission inertia.

[0102] Furthermore, the acquired motor speed data and transmission inertia data are simultaneously input into a dedicated computing circuit. The computing circuit performs a division operation on the two data according to a fixed logic. During the operation, a signal shaping circuit ensures the stability of the input data and avoids calculation deviations caused by data fluctuations. Through the precise calculation of the hardware circuit, a physical quantity that reflects the rate of change of motor speed is directly obtained. This physical quantity is the instantaneous acceleration characteristic quantity of the electric drive axle.

[0103] Furthermore, after the dynamic compensation processing unit is activated, it first analyzes the variation law of the instantaneous acceleration characteristic quantity. Combining this with the influence characteristics of transmission inertia on the mechanical response of the electric drive axle, it corrects and adjusts the instantaneous acceleration characteristic quantity moment by moment. During the adjustment process, factors such as mechanical damping and inertial delay caused by transmission inertia are fully considered. Through continuous signal calibration, the deviation of the instantaneous acceleration characteristic quantity caused by transmission inertia is eliminated, enabling the corrected characteristic quantity to more accurately reflect the actual mechanical motion state of the electric drive axle. After complete dynamic compensation adjustment, a standard physical quantity that can clearly define the mechanical disturbance frequency range is output; this physical quantity is the mechanical cutoff frequency of the electric drive axle.

[0104] In summary, by directly linking the dynamic operating parameters and inherent mechanical parameters of the electric drive axle, a core characteristic quantity reflecting the rate of change of motor speed is quickly obtained through a simple and physically meaningful correlation method. This characteristic quantity can respond in real time to the dynamic fluctuations of motor speed, accurately capture the changing trend of the mechanical motion state of the electric drive axle, avoid the delay caused by complex calculations, and provide real-time and highly correlated basic data for the subsequent calculation of the mechanical cutoff frequency. This meets the need for rapid perception of system dynamic changes in active disturbance rejection control, ensuring that the definition of the mechanical disturbance frequency range can closely follow the changes in the operating state of the electric drive axle.

[0105] In summary, by fully considering the inherent influence of transmission inertia on the mechanical response of the electric drive axle, dynamic compensation is used to correct the deviation in instantaneous acceleration characteristics caused by transmission inertia, making the final mechanical cutoff frequency more closely match the actual mechanical characteristics of the electric drive axle. This compensation process can counteract the interference from factors such as mechanical damping and inertial delay caused by transmission inertia, making the mechanical cutoff frequency value more accurate and avoiding the problem of frequency threshold mismatch between fixed parameter calculations and actual operating conditions. The accurate mechanical cutoff frequency provides a reliable threshold basis for subsequent low-pass filtering, ensuring more accurate extraction of external mechanical disturbance observations, thereby improving the suppression accuracy of the entire torque ripple suppression strategy for external mechanical disturbances and ensuring the smoothness and stability of the electric drive axle operation.

[0106] In this embodiment of the invention, the step of weighted summing of the compensation amount of the mechanical disturbance observation and the compensation amount of the electrical harmonic observation to obtain the comprehensive feedforward compensation amount of the electric drive bridge is specifically used for:

[0107] The feedforward gain of the observed mechanical disturbance is adjusted to obtain the first feedforward compensation component of the electric drive bridge;

[0108] The electrical harmonic disturbance observations are phase-advanced to obtain the second feedforward compensation component of the electric drive bridge;

[0109] The first feedforward compensation component and the second feedforward compensation component are vector-superimposed to obtain the comprehensive feedforward compensation amount of the electric drive bridge.

[0110] Specifically, the external mechanical disturbance observation values ​​of the electric drive bridge are connected to the feedforward gain adjustment circuit. This circuit has a fixed gain coefficient that is adapted to the mechanical characteristics of the electric drive bridge. The gain coefficient is set based on the mechanical structure parameters, load characteristics and disturbance suppression requirements of the electric drive bridge to ensure that the compensation requirements of mechanical disturbances can be accurately matched.

[0111] Furthermore, after the adjustment circuit is started, the signal amplitude of the input mechanical disturbance observation value is detected to obtain the real-time amplitude of the observation value. Then, the amplitude of the observation value is linearly adjusted according to the preset gain coefficient. During the adjustment process, the phase of the observation value is kept unchanged by the signal follower, and only its amplitude intensity is changed. At the same time, the amplitude calibration module monitors the adjusted signal amplitude in real time to ensure that the adjustment result meets the compensation accuracy requirements. The signal output after gain adjustment is the first feedforward compensation component of the electric drive bridge. This component can accurately correspond to the compensation amplitude required by the external mechanical disturbance.

[0112] Specifically, the internal electrical harmonic disturbance observation values ​​are transmitted to the phase lead correction unit. This unit has a built-in phase detection module and a phase adjustment module. First, the phase detection module captures the real-time phase information of the electrical harmonic disturbance observation values ​​to determine their current phase position and trend of change. At the same time, based on the response characteristics of the electric drive axle electrical system, a fixed phase lead angle is preset. This angle can cancel the phase lag of the electrical system and ensure that the compensation signal and the disturbance signal are accurately aligned in phase.

[0113] Specifically, the first feedforward compensation component and the second feedforward compensation component are simultaneously input to the vector superposition processing unit. This unit has a built-in dual-channel signal input interface and a vector synthesis module. First, the two input components are processed for signal synchronization. The clock synchronization circuit ensures that the sampling times of the two signals are completely consistent, avoiding superposition errors caused by time differences.

[0114] Furthermore, the phase adjustment module performs phase shift processing on the electrical harmonic disturbance observation value based on the detected real-time phase and the preset lead angle. By changing the phase start point of the signal, the phase of the adjusted signal is ahead of the original observation value by a preset angle. During the adjustment process, the frequency of the signal is kept constant through the phase-locked loop, and only the phase parameter is corrected. The output signal after phase lead correction is the second feedforward compensation component of the electric drive bridge. This component can accurately match the compensation requirements of the internal electrical harmonic disturbance in phase.

[0115] Furthermore, the vector synthesis module performs superposition operations based on the amplitude and phase information of the two components according to the rules of spatial vector synthesis. During the synthesis process, with the same coordinate system as the reference, the amplitudes of the first and second feedforward compensation components are respectively used as the vector magnitudes, and their phases are respectively used as the vector direction angles. A new vector signal is obtained through geometric synthesis. The magnitude and direction angle of this vector signal comprehensively reflect the superposition effect of the two compensation components. At the same time, the signal filtering module removes the noise interference generated during the superposition process to ensure the purity of the output signal. The final vector signal is the comprehensive feedforward compensation amount of the electric drive bridge.

[0116] In summary, by adjusting the amplitude of the observed mechanical disturbance by adapting the fixed gain coefficient to the mechanical characteristics of the electric drive axle, the compensation requirements of external mechanical disturbances can be precisely matched, ensuring that the adjusted first feedforward compensation component precisely offsets the external mechanical disturbance in amplitude. This adjustment process maintains the phase of the observed mechanical disturbance, optimizing only the amplitude intensity. Simultaneously, amplitude calibration ensures compensation accuracy, avoiding poor torque ripple suppression due to insufficient or excessive compensation amplitude. This provides a targeted and highly accurate foundation for comprehensive feedforward compensation, aligning with the core logic of precise external disturbance compensation in active disturbance rejection control.

[0117] In summary, to address the phase lag characteristic of electrical systems, the phase of observed electrical harmonic disturbances is adjusted by pre-setting a fixed lead angle. This ensures that the phase of the second feedforward compensation component accurately cancels the phase delay of the electrical disturbance, achieving phase synchronization between the compensation signal and the disturbance signal. During the correction process, the signal frequency remains constant, and only the phase parameter is corrected. This ensures that the compensation signal can accurately superimpose and cancel the internal electrical harmonic disturbances in the time domain, avoiding compensation failure due to phase deviation. This provides a precise, phase-adaptive compensation basis for the comprehensive feedforward compensation, enhancing the targeted suppression of internal electrical harmonic disturbances.

[0118] In summary, clock synchronization ensures consistent sampling times for the two compensation components. Based on space vector synthesis rules, comprehensive fusion of amplitude and phase is achieved, enabling the integrated feedforward compensation to simultaneously cover the compensation requirements of both external mechanical disturbances and internal electrical harmonic disturbances, forming a comprehensive compensation scheme that accommodates both types of disturbances. During the superposition process, filtering removes clutter interference, ensuring the purity of the compensation and preventing mutual interference between the two types of compensation components. The resulting integrated feedforward compensation accurately and comprehensively offsets the main causes of torque pulsation, significantly improving the smoothness of the electric drive bridge torque output. This fully demonstrates the technical advantages of multi-disturbance collaborative suppression in active disturbance rejection control, providing an efficient and comprehensive compensation basis for the generation of subsequent switching control sequences.

[0119] In this embodiment of the invention, the calculation formula for the comprehensive feedforward compensation amount is specifically used for:

[0120]

[0121] This is the comprehensive feedforward compensation amount. This is the first feedforward compensation component. The observed values ​​of the mechanical disturbance are... This is the second feedforward compensation component. The electrical harmonic disturbance observation value, The differential time constant is The change in the observed internal electrical disturbance is the amount of change. This represents the sampling time interval.

[0122] Specifically, the mechanical disturbance observations are derived from the frequency band separation processing of the quadrature-axis current feedback. Using the mechanical cutoff frequency corresponding to the motor speed as the filtering parameter, a low-pass filter is used to separate the external mechanical disturbance-related signal from the quadrature-axis current feedback; this signal is the mechanical disturbance observation. The first feedforward compensation component is obtained by adjusting the feedforward gain of the mechanical disturbance observation. During the adjustment process, a fixed gain coefficient is set according to the mechanical characteristics of the electric drive bridge, and the amplitude of the mechanical disturbance observation is precisely adjusted to ultimately form the first feedforward compensation component. The electrical harmonic disturbance observations also originate from the frequency band separation of the quadrature-axis current feedback. Using the electrical harmonic frequency as the center frequency, a band-pass filter is used to extract the internal electrical harmonic-related disturbance signal from the quadrature-axis current feedback; this signal is the electrical harmonic disturbance observation. The second feedforward compensation component is obtained by performing phase lead correction on the electrical harmonic disturbance observation. A fixed lead angle is preset according to the phase lag characteristics of the electrical system to correct the phase of the electrical harmonic disturbance observation, resulting in the second feedforward compensation component. The differential time constant is a fixed parameter pre-set based on the dynamic response characteristics of the electric drive axle electrical system, used to adapt to the response rate of changes in internal electrical disturbance observations. The change in internal electrical disturbance observations is calculated by continuously acquiring electrical harmonic disturbance observations at two adjacent sampling times, subtracting the previous observation from the later one, thus reflecting the real-time changes in the electrical harmonic disturbance observations. The sampling time interval is a fixed time parameter preset by the system, representing the time interval between two adjacent acquisitions of electrical harmonic disturbance observations, ensuring a stable temporal pattern in the acquisition of electrical harmonic disturbance observations.

[0123] Furthermore, through the collaborative calculation of multi-dimensional components, a comprehensive feedforward compensation amount capable of fully offsetting the torque pulsation causes of the electric drive axle is accurately synthesized. By correlating the first feedforward compensation component with the mechanical disturbance observation, targeted compensation for external mechanical disturbances is achieved, ensuring that the compensation amplitude matches the mechanical disturbance. By combining the second feedforward compensation component with the electrical harmonic disturbance observation, precise phase compensation for internal electrical harmonic disturbances is completed, ensuring that the compensation signal remains synchronized with the electrical disturbance in phase. By coordinating the differential time constant with the change in the internal electrical disturbance observation and the sampling time interval, the dynamic change trend of the internal electrical disturbance is captured, and the development of the disturbance is predicted in advance, enabling timely compensation for rapidly changing electrical disturbances. The comprehensive feedforward compensation amount formed by the combined action of these three components can comprehensively cover external mechanical disturbances and internal electrical harmonic disturbances and their dynamic changes, providing a precise compensation basis for the generation of subsequent switching control sequences and effectively suppressing the torque pulsation of the electric drive axle.

[0124] In summary, as the observed mechanical disturbance increases, the first feedforward compensation component, after feedforward gain adjustment, increases synchronously, thereby strengthening the portion of the comprehensive feedforward compensation that addresses external mechanical disturbances and more effectively counteracts the increased mechanical disturbance. When the observed electrical harmonic disturbance increases, the second feedforward compensation component, after phase lead correction, increases accordingly, and the compensation strength for internal electrical harmonic disturbances in the comprehensive feedforward compensation also increases synchronously, ensuring effective suppression of electrical harmonic disturbances. When the change in the observed internal electrical disturbance increases, combined with a fixed differential time constant and sampling time interval, the corresponding compensation component increases accordingly, enabling the comprehensive feedforward compensation to quickly respond to changes in electrical disturbances and adjust the compensation strength in a timely manner to adapt to the dynamic changes in disturbances. The first feedforward compensation component, the second feedforward compensation component, and the compensation component corresponding to the dynamic changes in internal electrical disturbances are all adjusted synchronously according to the changes in their respective input signals, ultimately working together to drive the comprehensive feedforward compensation to make a precise and comprehensive response, always maintaining effective compensation capability for various disturbances.

[0125] In this embodiment of the invention, when scaling the motor torque constant of the electric drive axle based on the target torque value to obtain the quadrature-axis current reference value of the electric drive axle, it is specifically used for:

[0126] The scaling factor of the electric drive axle is determined based on the changing trend of the target torque value;

[0127] The product of the motor torque constant and the scaling factor is taken as the equivalent motor torque constant of the electric drive bridge.

[0128] The quotient of the target torque value and the equivalent motor torque constant is used as the reference value of the quadrature-axis current of the electric drive bridge.

[0129] Specifically, the target torque value signal of the electric drive axle is input, and the signal is continuously captured and stored through the data acquisition module to establish a time series database of the target torque value, ensuring that the specific value of the target torque value at different times can be completely recorded.

[0130] Specifically, the preset motor torque constant is retrieved from the system parameter storage unit of the electric drive axle. This constant is an inherent performance parameter of the motor, which directly reflects the correspondence between the motor output torque and the input current.

[0131] Specifically, the target torque value of the electric drive bridge and the obtained equivalent motor torque constant are input to the division operation unit respectively to ensure that the two signals are synchronized when input, and to avoid the operation result being affected by the input timing difference.

[0132] Furthermore, the signal processing unit compares the target torque value in the time series moment by moment to determine whether its value changes continuously, continuously, or remains stable. Simultaneously, it calculates the magnitude of the target torque value change per unit time to determine the rate of change. Based on a preset rule corresponding to the change trend and scaling factor, when the target torque value continuously increases and the rate of change is rapid, an appropriate amplification scaling factor is selected; when the target torque value continuously decreases and the rate of change is rapid, an appropriate reduction scaling factor is selected; when the target torque value remains stable, a base scaling factor with a value of 1 is selected. This ensures that the scaling factor accurately matches the change state of the target torque value, and the final determined factor is the scaling factor of the electric drive axle.

[0133] Furthermore, the retrieved motor torque constant and the scaling factor determined in the previous step are simultaneously input into the multiplication circuit. The circuit performs a product calculation on the two values ​​through its internal hardware logic. During the calculation process, a signal calibration module monitors the calculation process in real time to avoid deviations in the results due to circuit noise or numerical errors, ensuring that the accuracy of the product result meets the system control requirements. The value obtained after the multiplication operation can dynamically adjust the original motor torque constant according to the changing trend of the target torque value. This adjusted value is the equivalent motor torque constant of the electric drive axle.

[0134] Furthermore, the division unit performs a division operation on the target torque value and the equivalent motor torque constant according to a fixed operational logic. During the operation, an amplitude limiting module ensures that the result will not exceed the safe current range of the electric drive bridge. This result directly reflects the magnitude of the quadrature-axis current required to achieve the target torque value, and the final output result is the reference value of the quadrature-axis current of the electric drive bridge.

[0135] In summary, by continuously monitoring the time-series data of the target torque value, the system accurately determines its increasing, decreasing, or stable state and rate of change, enabling the determined scaling factor to dynamically adapt to the real-time changes in the target torque. This approach avoids the insufficient adaptability issues caused by using fixed coefficients, ensuring a high degree of match between the scaling factor and the torque control target. This provides a scientific basis for the subsequent dynamic adjustment of the motor torque constant, aligning with the core logic of dynamic optimization of control parameters based on system targets in active disturbance rejection control. It also allows the calculation of the quadrature-axis current reference value to closely follow changes in torque demand, enhancing the flexibility and specificity of the control strategy.

[0136] In summary, by combining the torque constant with a dynamic scaling factor, the inherent torque constant of the motor is adaptively adjusted, enabling the equivalent motor torque constant to accurately reflect the actual torque-current correspondence under the target torque variation trend. This adjustment process preserves the inherent characteristics of the motor torque constant while incorporating the dynamic requirements of the target torque through the scaling factor. This avoids the limitation of a fixed torque constant being unable to adapt to different torque operating conditions, providing accurate characteristic parameter support for the calculation of the quadrature-axis current reference value. This ensures that the current reference value can accurately map to the torque control target, improving the accuracy of torque control.

[0137] In summary, by directly performing numerical correlation calculations, a standard value for the quadrature-axis current that accurately achieves the target torque is obtained. This reference value simultaneously integrates the inherent characteristics of the motor and the dynamic requirements of the target torque, avoiding current command deviations caused by parameter mismatches. Compared to fixed-parameter calculation methods, the quadrature-axis current reference value obtained by this method is more targeted, providing a clear and accurate control benchmark for subsequent current error calculations and voltage command generation. This ensures that the generation of the switching control sequence accurately targets the torque control objective, effectively improving the accuracy and stability of the electric drive bridge torque output and further enhancing the torque ripple suppression effect.

[0138] In this embodiment of the invention, when performing space vector modulation on the integrated feedforward compensation amount and the quadrature-axis current reference value to obtain the switching control sequence of the electric drive bridge, it is specifically used for:

[0139] The current error of the electric drive bridge is obtained by subtracting the cross-axis current reference value from the cross-axis current feedback value.

[0140] The current error is integrally adjusted to obtain the first voltage command component of the electric drive bridge;

[0141] By integrating the first voltage command component with the comprehensive feedforward compensation, the switching control sequence of the electric drive bridge is obtained.

[0142] Specifically, the quadrature axis current reference value and the quadrature axis current feedback value of the electric drive bridge are simultaneously connected to the difference calculation circuit. This circuit has a dual-channel signal synchronous reception function. The internal clock synchronization module ensures that the two signals are collected at the same time node, avoiding calculation errors caused by timing differences.

[0143] Specifically, the obtained current error signal is transmitted to the integral adjustment unit, which has a built-in integral operation module and an error correction module. The integral operation module uses hardware circuitry to implement continuous integration, which can perform real-time accumulation calculation of the current error signal.

[0144] Specifically, the first voltage command component and the comprehensive feedforward compensation are connected to the signal fusion processing unit. This unit is equipped with a dual-channel signal preprocessing module, which first performs amplitude calibration and phase synchronization on the two input signals. The amplitude calibration module ensures that the amplitude range of the two signals is consistent, and the phase synchronization module keeps the phase changes of the two signals coordinated, eliminating phase difference interference between the signals.

[0145] Furthermore, the arithmetic circuit performs numerical comparisons of the two signals according to fixed logic, subtracting the real-time value of the quadrature axis current feedback from the real-time value of the quadrature axis current reference value. During the calculation process, the signal shaping module filters high-frequency noise in the two signals to ensure the stability and purity of the input signal. At the same time, the amplitude verification unit monitors the rationality of the calculation result to prevent abnormal values ​​from exceeding the system's allowable range. The final calculation result is the current error of the electric drive bridge.

[0146] Furthermore, during operation, the integral control unit first assesses the amplitude of the current error signal, distinguishing its positive / negative nature and magnitude. Then, it accumulates the error signal moment-by-moment according to integral logic, fully considering the duration and rate of change of the error during accumulation to ensure the integral result comprehensively reflects the cumulative effect of the error. Simultaneously, the error correction module monitors the integral result in real time. When the integral value approaches a preset saturation threshold, it automatically activates a limiting protection mechanism to prevent integral saturation from causing control failure. The signal output after complete integral control is the first voltage command component of the electric drive bridge.

[0147] Furthermore, the signal fusion processing unit uses vector synthesis to fuse the two signals. Using the same coordinate system as a reference, the first voltage command component and the comprehensive feedforward compensation are treated as two vectors, and geometrically synthesized based on their amplitude and phase information to obtain a fused total voltage command signal. Subsequently, the total voltage command signal is input to the space vector modulation module. This module, based on the topology of the electric drive bridge inverter, maps the total voltage command signal to the on / off logic of each switch in the inverter, defining the timing sequence of each switch within each switching cycle, and generating a series of ordered switching control signals. These signals, arranged and combined according to a preset timing sequence, constitute the switching control sequence of the electric drive bridge.

[0148] In summary, by directly comparing the quadrature-axis current reference value, which reflects the target demand, with the quadrature-axis current feedback value, which reflects the actual operating state, the degree of deviation between the two is accurately quantified. This error value can intuitively reflect the deviation of current control, providing a clear basis for correction in subsequent adjustment stages. The difference process relies on a synchronous sampling mechanism to avoid the influence of timing deviations, while filtering signal noise to ensure the authenticity of the error value. This aligns with the core requirement of accurately sensing system deviations in active disturbance rejection control, allowing subsequent compensation and adjustment to be targeted, laying the foundation for improving torque control accuracy.

[0149] In summary, integral regulation can continuously accumulate and calculate current errors, taking into account both the magnitude and duration of the error, effectively eliminating static errors and ensuring the steady-state accuracy of current control. During regulation, a limiting protection mechanism prevents system instability caused by integral saturation, while dynamically responding to error changes, ensuring that the first voltage command component of the output can accurately adapt to error correction requirements, providing a scientific adjustment direction and amplitude for voltage control.

[0150] In summary, this fusion process achieves a synergistic effect of error correction and disturbance compensation. The first voltage command component precisely adjusts the current deviation, and the comprehensive feedforward compensation offsets the effects of external mechanical disturbances and internal electrical harmonic disturbances in advance. The two combined form a comprehensive control logic. Amplitude calibration and phase synchronization ensure the coordination of the fusion, and then space vector modulation is used to convert it into the switching transistor action sequence. This allows the switching control sequence to not only correct the current deviation but also predict and suppress various disturbances, significantly improving the smoothness and stability of the electric drive bridge torque output. It fully leverages the advantages of active disturbance rejection control and meets the requirements of high-precision torque control for electric drive bridges.

[0151] Compared with the prior art, the present invention has the following beneficial effects:

[0152] 1. This invention accurately acquires the three-phase current, motor speed, and target torque value of the electric drive axle. Through Clarke and Parker transforms, it obtains a precise quadrature-axis current feedback. Using the mechanical cutoff frequency and electrical harmonic frequency corresponding to the motor speed as filtering parameters, it achieves precise separation of external mechanical disturbance observations and internal electrical disturbance observations, ensuring comprehensive and accurate identification of both types of disturbances. A comprehensive feedforward compensation is formed through feedforward gain adjustment, phase lead correction, and vector superposition. Simultaneously, a suitable quadrature-axis current reference value is obtained by dynamically scaling the motor torque constant based on the target torque value. This ensures that the compensation strategy and current control benchmark accurately match the system operating state, significantly improving the targeting and accuracy of torque ripple suppression and resulting in smoother torque output from the electric drive axle.

[0153] 2. This invention generates a switching control sequence by integrating the feedforward compensation and the quadrature-axis current reference value through space vector modulation. It combines the disturbance prediction and suppression capabilities of feedforward compensation with the deviation correction capabilities of current closed-loop regulation, thus both proactively offsetting various disturbances and correcting current deviations in real time, significantly improving control response speed and stability. Dynamically adaptable mechanical cutoff frequency, flexibly adjustable scaling factor, and precise phase correction enable the system to respond to changes in operating status in real time, effectively enhancing the adaptability of the electric drive axle under different operating conditions, reducing mechanical wear and energy consumption caused by torque pulsation, extending equipment lifespan, and simultaneously improving the dynamic response capability and steady-state accuracy of torque control to meet high-precision drive requirements.

[0154] like Figure 2 The diagram shown is a functional block diagram of an electric drive bridge torque ripple suppression system based on active disturbance rejection control provided in an embodiment of the present invention.

[0155] The electric drive bridge torque ripple suppression system 100 based on active disturbance rejection control (ADRC) described in this invention can be installed in electronic devices. Depending on the functions implemented, the electric drive bridge torque ripple suppression system 100 may include a data acquisition module 101, a quadrature-axis current feedback module 102, a disturbance observation module 103, a comprehensive feedforward compensation module 104, a quadrature-axis current reference module 105, and a switch control sequence module 106. The modules described in this invention can also be referred to as units, which are a series of computer program segments that can be executed by the processor of an electronic device and perform a fixed function, stored in the memory of the electronic device.

[0156] In this embodiment, the functions of each module / unit are as follows:

[0157] The data acquisition module acquires the three-phase current, motor speed, and target torque value from the electric drive axle.

[0158] The quadrature-axis current feedback module performs coordinate transformation on the three-phase current to obtain the quadrature-axis current feedback of the electric drive bridge;

[0159] The disturbance observation module uses the mechanical cutoff frequency and electrical harmonic frequency corresponding to the motor speed as filtering parameters to perform frequency band separation on the quadrature axis current feedback, thereby obtaining the external mechanical disturbance observation value and the internal electrical disturbance observation value of the electric drive bridge.

[0160] The integrated feedforward compensation module weights and sums the compensation amounts of the mechanical disturbance observations and the electrical harmonic observations to obtain the integrated feedforward compensation amount of the electric drive bridge.

[0161] The quadrature axis current reference value module scales the motor torque constant of the electric drive bridge based on the target torque value to obtain the quadrature axis current reference value of the electric drive bridge;

[0162] The switching control sequence module performs space vector modulation on the integrated feedforward compensation amount and the quadrature axis current reference value to obtain the switching control sequence of the electric drive bridge.

[0163] In the several embodiments provided by this invention, it should be understood that the disclosed methods and systems can be implemented in other ways. For example, the system embodiments described above are merely illustrative; for instance, the division of modules is only a logical functional division, and other division methods may be used in actual implementation.

[0164] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0165] Furthermore, the functional modules in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or in the form of hardware plus software functional modules.

[0166] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0167] The embodiments of this application can acquire and process relevant data based on artificial intelligence technology. Artificial intelligence is the theory, method, technology, and application system that uses digital computers or machines controlled by digital computers to simulate, extend, and expand human intelligence, perceive the environment, acquire knowledge, and use that knowledge to obtain optimal results.

[0168] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A torque ripple suppression method for an electric drive axle based on active disturbance rejection control, characterized in that, The method comprises: acquiring three-phase current, motor speed and target torque value in the electric drive axle; coordinate transformation is carried out on the three-phase current to obtain the quadrature-axis current feedback of the electric drive axle; band separation is carried out on the quadrature-axis current feedback by taking mechanical cutoff frequency and electrical harmonic frequency as filter parameters to obtain external mechanical disturbance observation value and internal electrical disturbance observation value of the electric drive axle, comprising: calculating the mechanical cutoff frequency of the electric drive axle based on the motor speed and the transmission inertia of the electric drive axle; taking the product value of the power supply fundamental frequency of the electric drive axle and the target electrical harmonic number of the electric drive axle as the electrical harmonic frequency of the electric drive axle; low-pass filtering the quadrature-axis current feedback by taking the mechanical cutoff frequency as the threshold frequency to obtain the external mechanical disturbance observation value of the electric drive axle; band-pass filtering the quadrature-axis current feedback by taking the electrical harmonic frequency as the center frequency to obtain the internal electrical disturbance observation value of the electric drive axle; weighting and summing the compensation of the mechanical disturbance observation value and the compensation of the electrical disturbance observation value to obtain the comprehensive feedforward compensation of the electric drive axle; scaling the motor torque constant of the electric drive axle based on the target torque value to obtain the quadrature-axis current reference value of the electric drive axle; spatial vector modulation is carried out on the comprehensive feedforward compensation and the quadrature-axis current reference value to obtain the switching control sequence of the electric drive axle.

2. The torque ripple suppression method for electric drive axle based on active disturbance rejection control according to claim 1, characterized in that, The acquisition of three-phase current, motor speed and target torque value in the electric drive axle comprises: analog-to-digital conversion is carried out on the phase winding current in the electric drive axle to obtain the three-phase current of the electric drive axle; the motor sensor signal in the electric drive axle is analyzed to obtain the motor speed of the electric drive axle; the torque instruction value of the internal register in the electric drive axle is read through the data interface of the motor controller to obtain the target torque value of the electric drive axle.

3. The torque ripple suppression method for electric drive axle based on active disturbance rejection control according to claim 1, characterized in that, The coordinate transformation of the three-phase current to obtain the quadrature-axis current feedback of the electric drive axle comprises: Clarke transformation is carried out on the three-phase current to obtain the current component of the electric drive axle; Parker transformation is carried out on the current component to obtain the quadrature-axis current feedback of the electric drive axle.

4. The torque ripple suppression method for electric drive axle based on active disturbance rejection control according to claim 1, characterized in that, The calculation of the mechanical cutoff frequency of the electric drive axle based on the motor speed and the transmission inertia of the electric drive axle comprises: taking the ratio of the motor speed and the transmission inertia as the instantaneous acceleration characteristic quantity of the electric drive axle; dynamic compensation is carried out on the instantaneous acceleration characteristic quantity based on the transmission inertia to obtain the mechanical cutoff frequency of the electric drive axle.

5. The torque ripple suppression method for electric drive axle based on active disturbance rejection control according to claim 1, characterized in that, The weighting and summing of the compensation of the mechanical disturbance observation value and the compensation of the electrical disturbance observation value to obtain the comprehensive feedforward compensation of the electric drive axle comprises: feedforward gain adjustment is carried out on the mechanical disturbance observation value to obtain the first feedforward compensation component of the electric drive axle; phase lead correction is carried out on the electrical disturbance observation value to obtain the second feedforward compensation component of the electric drive axle; vector superposition is carried out on the first feedforward compensation component and the second feedforward compensation component to obtain the comprehensive feedforward compensation of the electric drive axle.

6. The torque ripple suppression method for electric drive axle based on active disturbance rejection control according to claim 5, characterized in that, The calculation formula of the comprehensive feedforward compensation quantity comprises: for the combined feedforward compensation quantity, for the first feedforward compensation component, for the mechanical disturbance observation, for the second feedforward compensation component, for the electrical disturbance observation, for a differentiation time constant, for a change in the internal electrical disturbance observation, for a sampling time interval.

7. The torque ripple suppression method for electric drive axle based on active disturbance rejection control according to claim 1, characterized in that, The scaling of the motor torque constant of the electric drive axle based on the target torque value to obtain the quadrature-axis current reference value of the electric drive axle comprises: Determining the scaling coefficient of the electric drive axle according to the variation trend of the target torque value; Taking the product of the motor torque constant and the scaling coefficient as the equivalent motor torque constant of the electric drive axle; Taking the quotient of the target torque value and the equivalent motor torque constant as the quadrature-axis current reference value of the electric drive axle.

8. The torque ripple suppression method for electric drive axle based on active disturbance rejection control according to claim 1, characterized in that, The space vector modulation of the comprehensive feedforward compensation quantity and the quadrature-axis current reference value to obtain the switching control sequence of the electric drive axle comprises: The difference between the quadrature-axis current reference value and the quadrature-axis current feedback quantity to obtain the current error of the electric drive axle; The integral regulation of the current error to obtain the first voltage instruction component of the electric drive axle; The fusion of the first voltage instruction component and the comprehensive feedforward compensation quantity to obtain the switching control sequence of the electric drive axle.

9. A torque ripple suppression system for an electric drive axle based on active disturbance rejection control for implementing a torque ripple suppression method for an electric drive axle based on active disturbance rejection control according to any one of claims 1 to 8, characterized in that The system comprises: A data acquisition module that acquires three-phase currents, a motor speed, and a target torque value in an electric drive axle; A quadrature-axis current feedback quantity module that performs coordinate transformation on the three-phase currents to obtain a quadrature-axis current feedback quantity of the electric drive axle; A disturbance observation value module that performs band separation on the quadrature-axis current feedback quantity with a mechanical cutoff frequency and an electrical harmonic frequency as filter parameters to obtain an external mechanical disturbance observation value and an internal electrical disturbance observation value of the electric drive axle, comprising: Calculating a mechanical cutoff frequency of the electric drive axle based on the motor speed and a transmission inertia of the electric drive axle; Taking the product of a power supply fundamental frequency of the electric drive axle and a target electrical harmonic number of the electric drive axle as an electrical harmonic frequency of the electric drive axle; Low-pass filtering the quadrature-axis current feedback quantity with the mechanical cutoff frequency as a threshold frequency to obtain an external mechanical disturbance observation value of the electric drive axle; Band-pass filtering the quadrature-axis current feedback quantity with the electrical harmonic frequency as a center frequency to obtain an internal electrical disturbance observation value of the electric drive axle; A comprehensive feedforward compensation quantity module that performs weighted summation on the compensation quantity of the mechanical disturbance observation value and the compensation quantity of the electrical disturbance observation value to obtain a comprehensive feedforward compensation quantity of the electric drive axle; A quadrature-axis current reference value module that scales the motor torque constant of the electric drive axle based on the target torque value to obtain a quadrature-axis current reference value of the electric drive axle; A switching control sequence module that performs space vector modulation on the comprehensive feedforward compensation quantity and the quadrature-axis current reference value to obtain a switching control sequence of the electric drive axle.

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