A power smooth control method for new energy commercial vehicle reversing

Abstract

The application provides a power smooth control method for new energy commercial vehicle reversing, which solves the problems of torque mutation and vehicle jitter caused by reusing forward gear torque MAP during reversing, and solves the problems of direct output torque of throttle transient step signal, large impact and poor precision during low-speed reversing. The method is executed by a vehicle controller VCU and includes the following control steps: S1, reversing mode recognition and switching; S2, reconstructing reversing exclusive demand torque MAP, the torque MAP is designed with low torque gradient and high linearity output, which greatly limits the torque instantaneous change rate; S3, throttle pedal transient passivation filtering processing, the filtering logic is an independent algorithm for the reversing mode, which is turned off in the forward gear, and the 5-step processing of throttle state grading, grading adaptive filtering, torque gradient limiting, small jitter dead zone filtering and output closed-loop correction is realized to achieve accurate passivation and smoothing of different throttle operation actions; and S4, torque output.

Description

Technical Field

[0001] This invention relates to the technical field of power control for the whole vehicle controller of new energy commercial vehicles, specifically a method for smooth power control when a new energy commercial vehicle is reversing. Background Technology

[0002] With the widespread adoption of new energy hybrid commercial vehicles in infrastructure construction sites and mining projects, dump trucks, muck trucks, and concrete mixer trucks need to perform delicate operations such as unloading, loading, and alignment by reversing at low speeds for extended periods. Existing vehicle power control solutions have the following significant shortcomings: There is no independent reversing control logic. The whole vehicle reuses the universal torque MAP curve for forward gears. In order to take into account forward conditions such as highway acceleration and hill climbing, the universal MAP has a large torque gradient and poor linearity. When reversing, even a slight release of the accelerator will cause a sudden torque change, resulting in obvious lurching and shaking of the vehicle. The handling feel at low speeds is extremely poor.

[0003] The accelerator pedal requires no special passivation treatment for reversing, and the accelerator step signal is directly converted into drive torque. Construction site drivers frequently tap the accelerator to fine-tune the vehicle speed, and the transient torque fluctuations are amplified by the transmission system, resulting in obvious jerking of the whole vehicle, poor driving comfort, and long-term vibration will also aggravate the fatigue wear of the frame, suspension and drive shaft.

[0004] In summary, existing power control strategies for new energy commercial vehicles cannot meet the smooth and precise control requirements of reversing operations in engineering scenarios, and have technical defects such as vibration, lurching, poor adaptability to working conditions, and low control precision. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a method for smooth power control during reversing of new energy commercial vehicles. This method solves the problems of sudden torque changes and vehicle jerking / vibration caused by reusing the forward gear torque MAP. It also solves the problems of large impact and poor accuracy during low-speed reversing caused by directly outputting torque from the transient step signal of the throttle.

[0006] A method for smooth power control when a new energy commercial vehicle is reversing, characterized in that it is executed by the vehicle control unit (VCU) and includes the following control steps: S1 reversing mode recognition and switching; The S2 reconstructs the torque MAP specifically for reversing, employing a low torque gradient and high linearity output design to significantly limit the instantaneous rate of torque change. The S3 accelerator pedal transient passivation filtering process uses an independent algorithm for reverse mode, with forward gears completely closed. It achieves precise passivation and smoothing for different accelerator pedal operation actions through a five-step progressive process: accelerator state grading → graded adaptive filtering → torque gradient limiting → micro-vibration dead zone filtering → output closed-loop correction. S4, Torque Output.

[0007] Its further features are: In step S1, the VCU collects the gear shift lever signal in real time. When it detects that the vehicle has engaged reverse gear, it automatically exits the general forward power control logic and enters reverse mode. After the vehicle shifts back to forward gear, it immediately exits reverse mode and restores the original vehicle torque control strategy. In step S2, a separately calibrated torque MAP for reversing is pre-stored to replace the universal torque curve for forward gears; under the same throttle opening, the slope of the torque increase and decrease for reversing is much smaller than that for forward gears. Step S3 includes the following steps: The S301 throttle dynamic characteristic parameters are calculated in real time. Based on the throttle opening data collected continuously, two sets of core characteristic parameters are calculated in real time to determine the driver's operating intention: Incremental change in throttle opening The difference between the throttle opening in the current cycle and the throttle opening in the previous cycle represents the magnitude of throttle change in a single operation. Throttle opening change rate The change in throttle opening per unit time represents the speed at which the driver presses / releases the throttle. By using two-dimensional parameters of amplitude and rate, it can accurately distinguish three driving intentions: fine-tuning, normal operation, and rapid operation. S302 throttle status classification, preset fixed calibration threshold, combined with and The reverse accelerator operation is divided into three independent working conditions: Minor fine-tuning of operating conditions: ≤Small threshold and ≤Low speed threshold, corresponding to the fine operation scenario where the driver slightly taps the pedal, makes minor adjustments to the throttle, and makes slight corrections to the opening. Rapid pedaling / loosening of the grease: ≥ the threshold for emergency stepping or ≥ High speed threshold, corresponding to sudden operation scenarios of the driver rapidly pressing the accelerator, rapidly releasing the accelerator, and urgently releasing the accelerator; Moderate normal operating conditions: All remaining throttle operation states other than the two types of operating conditions mentioned above, corresponding to the normal scenario where the driver normally and evenly presses and releases the throttle and smoothly adjusts the reversing speed; The S303 hierarchical adaptive filter matches differentiated independent filtering strategies with fixed calibration coefficients for three throttle operation conditions, achieving precise adaptation of smoothness and responsiveness. Minor fine-tuning operation: High-damping second-order low-pass filter is activated, and a high smoothing coefficient is used to deeply filter out minor throttle fluctuations and high-frequency jitter signals, smoothing out subtle opening changes to the maximum extent, ensuring constant reversing speed, and adapting to millimeter-level precise alignment operations. Medium-duty normal operating conditions: Activate medium-damped first-order low-pass filter with appropriate filter coefficient to efficiently filter out small-amplitude high-frequency interference signals from the throttle. At the same time, thanks to the fast response speed and no phase lag of the first-order filter, it ensures effective following of changes in throttle opening, accurately balances reversing smoothness and vehicle speed adjustment responsiveness, and completely avoids the slight power lag problem caused by composite filtering. It is suitable for normal constant speed fine-tuning reversing scenarios. Rapid pedaling / releasing of throttle: Activate variable slope limiting filter, which dynamically adjusts the slope of torque rise and fall to limit the effective operation intention, without forcibly smoothing out the effective operation intention, only limiting the torque change amplitude, thus eliminating the violent surging impact caused by high throttle operation, while retaining reasonable power rise and fall characteristics, ensuring the effectiveness of operation. The S304 torque gradient limiting, based on the output of the filtering algorithm, superimposes a hard limit strategy on the reversing torque change rate: preset the maximum reversing torque rise gradient and the maximum torque fall gradient. No matter how much the throttle signal changes, the required torque rise or fall value in a single control cycle must not exceed the preset gradient threshold. This forcibly eliminates step changes from the torque output end, forming a dual protection of algorithm filtering + torque limiting. The S305 features dead-zone filtering for minor throttle vibrations. It sets a specific dead-zone threshold for throttle opening when reversing. When the fluctuation in throttle opening is less than the dead-zone threshold, it is directly identified as mechanical vibration, foot tremor, or invalid signal interference. The current required torque is forcibly locked, and torque updates are not performed. Only when the change in throttle exceeds the dead-zone threshold will it respond to the driver's valid operating intention, completely solving the problem of continuous minor vibrations under idling micro-movement conditions. The S306 filter output closed-loop smoothing correction performs periodic closed-loop correction on the final filtered required torque. By comparing the difference in torque output before and after each period, if a momentary jump peak occurs, it automatically interpolates to smooth the transition, ensuring that the torque output is continuous, monotonous, without peaks or breaks throughout the entire process.

[0008] The present invention has the following beneficial effects: Significantly improved reversing smoothness: Low gradient torque MAP combined with throttle dulling eliminates low-speed throttle jerking and vibration, making on-site positioning and unloading operations more precise; Extend the lifespan of chassis components: reduce the impact of alternating torque during reversing, reduce fatigue wear on drive shafts, suspensions, and frames, and reduce vehicle maintenance costs; Improved safety at construction sites: Vehicles have greater controllability at low speeds, reducing the risk of collisions with personnel, equipment, and materials; Wide adaptability: The control logic can be quickly ported to various hybrid engineering commercial vehicles, including parallel, range-extended, and power-split types, requiring only matching of the corresponding calibration parameters. Detailed Implementation

[0009] A method for smooth power control when a new energy commercial vehicle is reversing, characterized in that it is executed by the vehicle control unit (VCU) and includes the following control steps: S1 Reverse Mode Recognition and Switching: VCU collects the gear shift lever signal in real time. When it recognizes that the vehicle has engaged reverse gear, it automatically exits the general forward power control logic and switches to reverse mode. After the vehicle switches back to forward gear, it immediately exits reverse mode and restores the original vehicle torque control strategy. S2 reconstructs a torque MAP specifically for reversing, pre-stores a separately calibrated torque MAP specifically for reversing, and uses it to replace the general torque curve for forward gears. The torque MAP adopts a low torque gradient and high linearity output design, which greatly limits the instantaneous rate of change of torque; under the same throttle opening, the slope of the increase and decrease of torque in reversing is much smaller than that in forward driving conditions. The S3 accelerator pedal transient passivation filtering process uses an independent algorithm for reverse mode, with forward gears completely disabled. It employs a five-step progressive processing approach: throttle state grading → tiered adaptive filtering → torque gradient limiting → micro-vibration dead zone filtering → output closed-loop correction. This achieves precise and smooth passivation for different throttle operation actions. The process includes the following steps: The S301 throttle dynamic characteristic parameters are calculated in real time. Based on the throttle opening data collected continuously, two sets of core characteristic parameters are calculated in real time to determine the driver's operating intention: Incremental change in throttle opening The difference between the throttle opening in the current cycle and the throttle opening in the previous cycle represents the magnitude of throttle change in a single operation. Throttle opening change rate The change in throttle opening per unit time represents the speed at which the driver presses / releases the throttle. By using two-dimensional parameters of amplitude and rate, it can accurately distinguish three driving intentions: fine-tuning, normal operation, and rapid operation. S302 throttle status classification, preset fixed calibration threshold, combined with and The reverse accelerator operation is divided into three independent working conditions: Minor fine-tuning of operating conditions: ≤Small threshold and ≤Low speed threshold, corresponding to the fine operation scenario where the driver slightly taps the pedal, makes minor adjustments to the throttle, and makes slight corrections to the opening. Rapid pedaling / loosening of the grease: ≥ the threshold for emergency stepping or ≥High-speed threshold, corresponding to sudden operational scenarios where the driver rapidly accelerates, rapidly releases the accelerator, or abruptly decelerates the accelerator; Moderate normal operating conditions: All remaining throttle operation states other than the two types of operating conditions mentioned above, corresponding to the normal scenario where the driver normally and evenly presses and releases the throttle and smoothly adjusts the reversing speed; The S303 hierarchical adaptive filter matches differentiated independent filtering strategies with fixed calibration coefficients for three throttle operation conditions, achieving precise adaptation of smoothness and responsiveness. Minor fine-tuning operation: High-damping second-order low-pass filter is activated, and a high smoothing coefficient is used to deeply filter out minor throttle fluctuations and high-frequency jitter signals, smoothing out subtle opening changes to the maximum extent, ensuring constant reversing speed, and adapting to millimeter-level precise alignment operations. Under moderate normal operating conditions: A medium-damped first-order low-pass filter is activated, with a suitable filter coefficient, to efficiently filter out small-amplitude high-frequency interference signals from the throttle. Simultaneously, thanks to the fast response speed and no phase lag of the first-order filter, it ensures effective tracking of throttle opening changes, precisely balancing reversing smoothness and vehicle speed adjustment responsiveness, completely avoiding the slight power lag problem caused by composite filtering, and is suitable for normal constant-speed fine-tuning reversing scenarios; Rapid pedaling / releasing of throttle: Activate variable slope limiting filter, which dynamically adjusts the slope of torque rise and fall to limit the effective operation intention, without forcibly smoothing out the effective operation intention, only limiting the torque change amplitude, thus eliminating the violent surging impact caused by high throttle operation, while retaining reasonable power rise and fall characteristics, ensuring the effectiveness of operation. The S304 torque gradient limiting, based on the filtering algorithm output, superimposes a hard limit strategy on the reversing torque change rate: preset maximum reversing torque rise gradient and maximum torque fall gradient, regardless of the magnitude of the throttle signal change, the required torque rise or fall value within a single control cycle must not exceed the preset gradient threshold, forcibly preventing step changes from the torque output end, forming a dual protection of algorithm filtering + torque limiting; The S305 features dead-zone filtering for minor throttle vibrations. It sets a specific dead-zone threshold for throttle opening during reversing. When the throttle opening fluctuation is less than the threshold, it is directly identified as mechanical vibration, foot tremor, or invalid signal interference, forcibly locking the current required torque and not performing torque updates. Only when the throttle change exceeds the dead-zone threshold will it respond to the driver's valid operating intention, completely resolving the problem of continuous minor vibrations under idling micro-movement conditions. The S306 filter output closed-loop smoothing correction performs periodic closed-loop correction on the final filtered required torque. By comparing the difference in torque output before and after the period, if an instantaneous jump peak occurs, it automatically interpolates to smooth the transition, ensuring that the torque output is continuous, monotonous, without peaks or breaks throughout the entire process. S4, Torque Output: Based on the smooth demand torque after graded passivation filtering, gradient limiting, and dead zone correction, combined with the low-gradient, high-linearity torque MAP output reference torque for reversing, the power source drive torque is distributed in a coordinated manner to output continuous and stable vehicle drive torque. Specific Implementation Taking new energy dump trucks as an example, the VCU control cycle is 10ms; the pre-calibrated thresholds are: small throttle opening threshold 2%, rapid throttle opening threshold 12%; low speed threshold 1.5% / 10ms, high speed threshold 6% / 10ms; throttle vibration dead zone threshold 0.8%; maximum torque change gradient limit for reversing 50Nm / 10ms; pre-calibrated reversing-specific torque MAP, the torque change slope under the same throttle opening is 35% of the forward general MAP.

[0011] When the vehicle enters the construction site for unloading, the driver engages reverse gear, and the VCU automatically switches to the reversing-only control mode.

[0012] Scenario 1: Minor Fine-tuning Operation The driver's foot trembled slightly, and the throttle opening fluctuated slightly between 4.1% and 4.8%. ≤2%, If the throttle fluctuation is less than 1.5% / 10ms, it is judged as a small-scale fine-tuning condition, and a large-damping second-order low-pass filter is activated; if the throttle fluctuation is less than 0.8% of the dead zone threshold, the VCU locks the current required torque and does not frequently adjust the drive torque.

[0013] Scenario 2: Moderate routine operating conditions The driver smoothly pressed the accelerator, and the throttle opening gradually increased from 5% to 11%. Between 2% and 12% Between 1.5% / 10ms and 6% / 10ms, the condition is determined to be a moderate normal operating condition. A medium-damped first-order low-pass filter is activated to smooth out minor disturbances while following the driver's operating intentions, resulting in a smooth increase in vehicle speed.

[0014] Scenario 3: Rapid pedal pressing The driver quickly increased the throttle opening from 4% to 18%. >12% and If the value is greater than 6% / 10ms, it is determined to be a rapid pedal depressing condition. The pure slope transition gradient limiting filtering strategy is activated. The VCU abandons the step torque output and strictly follows the maximum reverse torque change gradient limit of 50Nm / 10ms to perform a linear and smooth slope transition, which fully preserves the driver's acceleration intention while completely smoothing out the torque sudden change impact.

[0015] Under all operating conditions, the filtered output torque is further corrected by torque gradient hard limiting and closed-loop interpolation, and finally outputs smooth drive torque; after the vehicle shifts back to forward gear, it immediately exits the reverse-specific filter and reverse torque MAP, restoring the original vehicle power response characteristics.

[0016] Its reverse gear triggers an independent control mode, with the two sets of torque control logics for reversing and forward being isolated from each other; it independently reconstructs a low-gradient, high-linearity torque MAP specifically for reversing, without relying on the general calibration curve for forward gears; and it has a reversing-specific progressive throttle passivation filtering system, establishing a triple anti-impact mechanism of 'graded flexible filtering + torque gradient constraint + micro-vibration dead zone filtering' to suppress reversing torque fluctuations and jerking vibrations.

[0017] 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 invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0018] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for smooth power control when a new energy commercial vehicle is reversing, characterized in that, It is executed by the vehicle control unit (VCU) and includes the following control steps: S1 reversing mode recognition and switching; The S2 reconstructs the torque MAP specifically for reversing, employing a low torque gradient and high linearity output design to significantly limit the instantaneous rate of torque change. The S3 accelerator pedal transient passivation filtering process uses an independent algorithm for reverse mode, with forward gears completely closed. It achieves precise passivation and smoothing for different accelerator pedal operation actions through a five-step progressive process: accelerator state grading → graded adaptive filtering → torque gradient limiting → micro-vibration dead zone filtering → output closed-loop correction. S4, Torque Output.

2. The power smoothness control method for reversing a new energy commercial vehicle according to claim 1, characterized in that: In step S1, the VCU collects the gear shift lever signal in real time. When it detects that the vehicle has engaged reverse gear, it automatically exits the general forward power control logic and enters reverse mode. After the vehicle shifts back to forward gear, it immediately exits reverse mode and restores the original vehicle torque control strategy.

3. The power smoothness control method for reversing a new energy commercial vehicle according to claim 2, characterized in that: In step S2, a separately calibrated reverse torque-specific MAP is pre-stored to replace the general torque curve for forward gears; under the same throttle opening, the slope of the reverse torque increase and decrease is much smaller than that of the forward condition.

4. The power smoothness control method for reversing a new energy commercial vehicle according to claim 3, characterized in that, Step S3 includes the following steps: The S301 throttle dynamic characteristic parameters are calculated in real time. Based on the throttle opening data collected continuously, two sets of core characteristic parameters are calculated in real time to determine the driver's operating intention: Incremental change in throttle opening The difference between the throttle opening in the current cycle and the throttle opening in the previous cycle represents the magnitude of throttle change in a single operation. Throttle opening change rate The change in throttle opening per unit time represents the speed at which the driver presses / releases the throttle. By using two-dimensional parameters of amplitude and rate, it can accurately distinguish three driving intentions: fine-tuning, normal operation, and rapid operation. S302 throttle status classification, preset fixed calibration threshold, combined with and The reverse accelerator operation is divided into three independent working conditions: Minor fine-tuning of operating conditions: ≤Small threshold and ≤Low speed threshold, corresponding to the fine operation scenario where the driver slightly taps the pedal, makes minor adjustments to the throttle, and makes slight corrections to the opening. Rapid pedaling / loosening of the grease: ≥ the threshold for emergency stepping or ≥ High speed threshold, corresponding to sudden operation scenarios of the driver rapidly pressing the accelerator, rapidly releasing the accelerator, and urgently releasing the accelerator; Moderate normal operating conditions: All remaining throttle operation states other than the two types of operating conditions mentioned above, corresponding to the normal scenario where the driver normally and evenly presses and releases the throttle and smoothly adjusts the reversing speed; The S303 hierarchical adaptive filter matches differentiated independent filtering strategies with fixed calibration coefficients for three throttle operation conditions, achieving precise adaptation of smoothness and responsiveness. Minor fine-tuning operation: High-damping second-order low-pass filter is activated, and a high smoothing coefficient is used to deeply filter out minor throttle fluctuations and high-frequency jitter signals, smoothing out subtle opening changes to the maximum extent, ensuring constant reversing speed, and adapting to millimeter-level precise alignment operations. Medium-duty normal operating conditions: Activate medium-damped first-order low-pass filter with appropriate filter coefficient to efficiently filter out small-amplitude high-frequency interference signals from the throttle. At the same time, thanks to the fast response speed and no phase lag of the first-order filter, it ensures effective following of changes in throttle opening, accurately balances reversing smoothness and vehicle speed adjustment responsiveness, and completely avoids the slight power lag problem caused by composite filtering. It is suitable for normal constant speed fine-tuning reversing scenarios. Rapid pedaling / releasing of throttle: Activate variable slope limiting filter, which dynamically adjusts the slope of torque rise and fall to limit the effective operation intention, without forcibly smoothing out the effective operation intention, only limiting the torque change amplitude, thus eliminating the violent surging impact caused by high throttle operation, while retaining reasonable power rise and fall characteristics, ensuring the effectiveness of operation. The S304 torque gradient limiting, based on the output of the filtering algorithm, superimposes a hard limit strategy on the reversing torque change rate: preset the maximum reversing torque rise gradient and the maximum torque fall gradient. No matter how much the throttle signal changes, the required torque rise or fall value in a single control cycle must not exceed the preset gradient threshold. This forcibly eliminates step changes from the torque output end, forming a dual protection of algorithm filtering + torque limiting. The S305 features dead-zone filtering for minor throttle vibrations. It sets a specific dead-zone threshold for throttle opening when reversing. When the fluctuation in throttle opening is less than the dead-zone threshold, it is directly identified as mechanical vibration, foot tremor, or invalid signal interference. The current required torque is forcibly locked, and torque updates are not performed. Only when the change in throttle exceeds the dead-zone threshold will it respond to the driver's valid operating intention, completely solving the problem of continuous minor vibrations under idling micro-movement conditions. The S306 filter output closed-loop smoothing correction performs periodic closed-loop correction on the final filtered required torque. By comparing the difference in torque output before and after each period, if a momentary jump peak occurs, it automatically interpolates to smooth the transition, ensuring that the torque output is continuous, monotonous, without peaks or breaks throughout the entire process.