Steering oil pump control method and system for new energy commercial vehicle

Abstract

The invention provides a new energy commercial vehicle steering oil pump control method and system, and the method comprises the steps: S1, obtaining a rotating speed signal of a steering oil pump, and detecting the current and voltage of a steering oil pump motor at different rotating speeds when a vehicle steering wheel is in the center; s2, calculating the power of the steering oil pump motor at different rotating speeds according to the current and the voltage detected in the S1, and adding an offset value to each calculated power value to obtain a power threshold value; s3, the rotating speed, current and voltage signals of the steering oil pump motor are obtained in real time, the real-time power of the steering oil pump motor is calculated and compared with the power threshold value corresponding to the current rotating speed, and whether the vehicle has the steering requirement or not is judged; and S4, the target rotating speed of the steering oil pump motor is adjusted according to steering requirements. According to the method, the real-time power is calculated by using the existing current and voltage signals of the steering oil pump motor, and the steering requirement of a driver can be accurately judged by analyzing a rising edge or falling edge event in a power change curve.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of automobile steering oil pumps, and particularly relates to a new energy commercial vehicle steering oil pump control method and system. BACKGROUND

[0002] With the rapid popularization of new energy commercial vehicles, vehicle energy consumption optimization has become one of the core topics for improving the cruising range. The existing new energy commercial vehicles generally adopt a constant speed control strategy, that is, the steering oil pump is always maintained at the rated speed after the vehicle is powered on at high pressure to provide steering assistance at any time.

[0003] However, when the vehicle has no steering demand or the straight-line driving proportion is high, the steering oil pump still continuously outputs the maximum flow, and the steering oil pump still continuously runs, which inevitably causes unnecessary power consumption. At the same time, the long-time full-load operation of the motor and the pump body aggravates mechanical wear, noise and oil temperature rise, and shortens the service life. SUMMARY

[0004] To solve the problems in the prior art, the application aims to provide a new energy commercial vehicle steering oil pump control method and system, which automatically identifies whether the vehicle has steering demand and reduces the steering oil pump speed when there is no steering demand to reduce power consumption.

[0005] To achieve the above-mentioned purpose, the technical scheme of the application is as follows: A new energy commercial vehicle steering oil pump control method, comprising: S1, adjusting the speed of the steering oil pump motor, detecting the current and voltage of the steering oil pump motor when the steering wheel of the vehicle is in the central position at different speeds; S2, calculating the power of the steering oil pump motor at different speeds according to the current and voltage detected in S1, and adding an offset value to each calculated power value to obtain a power threshold, and establishing a speed-power threshold reference table when there is no steering demand; S3, acquiring the speed, current and voltage signals of the steering oil pump motor in real time, calculating the real-time power of the steering oil pump motor, and comparing the real-time power with the power threshold corresponding to the current speed to determine whether the vehicle has steering demand; S4, adjusting the target speed of the steering oil pump motor according to the steering demand.

[0006] Further, in S3, the condition for determining whether the vehicle has steering demand is: When the real-time power of the steering oil pump motor is greater than the power threshold corresponding to the current speed, a power rising edge is identified, and it is determined that there is steering demand; When the real-time power of the steering oil pump motor is less than the power threshold corresponding to the current speed, a power falling edge is identified, and it is determined that there is no steering demand.

[0007] Further, in S4, when there is a steering demand, set the target speed of the steering oil pump to a first preset speed, which is greater than the current speed; When there is no steering demand, after a preset time delay, set the target speed of the steering oil pump to a second preset speed, which is less than the current speed.

[0008] Further, the first preset speed is 1200 rpm.

[0009] Further, the second preset speed is 500 rpm.

[0010] Further, when there is no steering demand, the preset time delay is 30 seconds.

[0011] Further, when the steering oil pump motor switches from the current speed to the first preset speed, the speed is controlled to rise rapidly; when the steering oil pump motor switches from the current speed to the second preset speed, the speed is controlled to drop slowly.

[0012] Further, when the steering oil pump motor switches from the current speed to the first preset speed, the speed rising rate is 400 rpm / s; when the steering oil pump motor switches from the current speed to the second preset speed, the speed dropping rate is 50 rpm / s.

[0013] Further, in S2, the offset value is 100 W.

[0014] A new energy commercial vehicle steering oil pump control system, comprising: a signal acquisition module for acquiring the current, voltage and speed of the steering oil pump motor; a control module for receiving the current, voltage and speed, calculating the power of the steering oil pump motor when the steering wheel is in the center position, and establishing a speed-power threshold reference table when there is no steering demand; calculating the real-time power of the steering oil pump motor and comparing it with the power threshold corresponding to the current speed to determine whether there is a steering demand for the vehicle; an execution driving module for adjusting the target speed of the steering oil pump motor according to the steering demand.

[0015] Compared with the prior art, the new energy commercial vehicle steering oil pump control method has the following advantages: The present application uses the current and voltage signals of the steering oil pump motor to calculate the real-time power, and by analyzing the rising or falling edge events in the power change curve, the steering demand of the driver can be accurately determined without the need for additional hardware devices such as pressure sensors, torque sensors or angle sensors. This method not only simplifies the system structure, but also reduces the cost, while effectively avoiding the reliability problems that may be caused by the addition of sensors.

[0016] In addition, the application adopts the gradient adjustment mode of 'fast rise and slow fall' in the control strategy of steering assist, so as to optimize the speed and smoothness of the assist response. When the steering assist is needed, the system can quickly increase the motor speed, thereby ensuring the timeliness of the steering assist. When the demand for steering assist is reduced, the speed is slowly reduced to avoid the sudden reaction force of the steering wheel, thereby eliminating the hand feeling of the steering wheel. This design not only ensures the safety of driving, but also significantly improves the comfort of driving, makes the vehicle control more natural and smooth, and brings better use experience to the driver. BRIEF DESCRIPTION OF DRAWINGS

[0017] The accompanying drawings, which form a part of this application, are intended to provide further understanding of the application and are incorporated herein in their entirety. The schematic embodiments of the application and their descriptions are used to explain the application and do not constitute an improper limitation on the application. In the drawings: Figure 1 The overall flowchart provided for the embodiments of the application; Figure 2 The control system flowchart provided for the embodiments of the application. DETAILED DESCRIPTION

[0018] It should be noted that the embodiments in the application and the features in the embodiments can be combined with each other without conflict.

[0019] In the description of the application, it should be understood that the terms 'center', 'longitudinal', 'transverse', 'upper', 'lower', 'front','rear', 'left', 'right','vertical', 'horizontal', 'top', 'bottom', 'inner', 'outer' and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the application and simplifying the description, and do not indicate or imply that the devices or elements indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the application. In addition, the terms 'first','second' and the like are only for the purpose of description and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features limited by 'first','second' and the like can explicitly or implicitly include one or more features. In the description of the application, unless otherwise stated, the meaning of 'a plurality of' is two or more.

[0020] The application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0021] As Figure 1 shown, a new energy commercial vehicle steering oil pump control method, comprising: S1, adjusting the speed of the steering oil pump motor, detecting the current and voltage of the steering oil pump motor when the vehicle steering wheel is in the center position at different speeds; S2. Based on the current and voltage detected in S1, calculate the power of the steering pump motor at different speeds, and add an offset value to each calculated power value to obtain the power threshold. Establish a reference table of speed and power threshold when there is no steering requirement. S3. Real-time acquisition of the speed, current and voltage signals of the steering pump motor, calculation of the real-time power of the steering pump motor, and comparison with the power threshold corresponding to the current speed to determine whether the vehicle has a steering requirement; S4. Adjust the target speed of the steering oil pump motor according to steering requirements.

[0022] This invention utilizes the existing current, voltage, and speed signals of the steering pump motor to establish a reference table of steering wheel center position speed and power threshold; subsequently, during operation, the steering demand can be output simply by comparing the real-time power with the current threshold, and the target speed of the oil pump can be switched instantly. The steering wheel centering condition is precisely quantified and uniformly offset, eliminating misjudgments caused by oil temperature, oil viscosity, and component dispersion; the speed is immediately reduced when there is no steering, the vehicle's auxiliary energy consumption is reduced accordingly, and the range of new energy commercial vehicles is extended.

[0023] In a preferred embodiment of the present invention, in step S3, the condition for determining whether the vehicle requires steering is: When the real-time power of the steering pump motor is greater than the power threshold corresponding to the current speed, and the rising edge of the power is detected, it is determined that there is a steering demand. When the real-time power of the steering pump motor is less than the power threshold corresponding to the current speed, and a falling edge of the power is detected, it is determined that there is no steering demand.

[0024] Specifically, when there is a steering requirement, the oil flow resistance in the steering oil circuit increases, and the real-time power of the oil pump motor automatically increases. If it exceeds the corresponding power threshold, the rising edge is detected, and then it is considered that there is a steering requirement.

[0025] Rising edge detection: When the real-time power of the power steering pump motor changes from below the power threshold corresponding to the current speed to above the threshold, and this change occurs for the first time, it is called a "rising edge". In other words, in continuous power sampling, if the power at the current sampling moment is greater than the threshold, while the power at the previous sampling moment is less than or equal to the threshold, then a "rising edge" is detected.

[0026] The rising edge detection is used to determine the onset of steering demand. When a rising edge is detected, the system determines that the vehicle needs to steering, thereby triggering an increase in the oil pump speed to provide sufficient steering assistance. Detecting the rising edge ensures that steering demand is only recognized when there is a significant increase in power exceeding a threshold, avoiding misjudgments of steering demand due to brief power fluctuations or noise interference, thus improving the accuracy and reliability of the judgment.

[0027] Falling edge detection: When the real-time power of the power steering pump motor changes from above the power threshold corresponding to the current speed to below the threshold, and this change occurs for the first time, it is called a "falling edge". In other words, in continuous power sampling, if the power at the current sampling moment is less than the threshold, while the power at the previous sampling moment is greater than or equal to the threshold, then a "falling edge" is detected.

[0028] Falling edge detection is used to determine the end of steering demand. When a falling edge is detected, the system determines that the vehicle has no steering demand, thereby triggering a reduction in the oil pump speed to reduce unnecessary energy consumption. Falling edge detection ensures that the end of steering demand is only identified when there is a significant drop in power below a threshold, avoiding misjudgment of the end of steering demand due to a brief power drop, and further improving the accuracy and stability of the judgment.

[0029] In a preferred embodiment of the present invention, in S4, when there is a steering requirement, the target speed of the steering oil pump is set to a first preset speed, which is greater than the current speed; When there is no steering requirement, after a preset delay, the target speed of the steering pump is set to a second preset speed, which is less than the current speed.

[0030] Specifically, when a steering demand is detected (power rise edge), the system sets the target speed of the steering pump motor to a first preset speed, which is higher than the current speed. By immediately increasing the speed, the system can quickly respond to the driver's steering operation, ensuring the timeliness and effectiveness of steering assistance.

[0031] When no steering demand is detected (power drop-off edge), the system does not immediately reduce the engine speed. Instead, it delays for a preset period (e.g., 30 seconds) before setting the target speed to a second preset speed, which is lower than the current speed. This delay mechanism avoids frequent speed switching caused by brief power fluctuations, improving system stability and reliability. By reducing the engine speed, the system reduces unnecessary energy consumption when there is no steering demand, improving the overall vehicle energy efficiency.

[0032] In a preferred embodiment of the present invention, the first preset rotational speed is 1200 rpm.

[0033] Specifically, when a steering demand is detected (power rise edge), the system immediately increases the oil pump speed to 1200 rpm to ensure timely response of the power steering assist and avoid steering delay or insufficient assistance due to insufficient speed. The 1200 rpm speed setting ensures power steering assist while avoiding unnecessary high-speed operation, thereby reducing energy consumption and improving the overall vehicle energy efficiency.

[0034] In a preferred embodiment of the present invention, the second preset rotational speed is 500 rpm.

[0035] Specifically, when no steering requirement is detected, the system reduces the target speed of the steering pump to 500 rpm. By reducing the speed when no steering is needed, the system minimizes energy waste while maintaining steering functionality, thus improving the overall vehicle energy efficiency. Low-speed operation reduces mechanical wear on the pump motor, extending the pump's lifespan. Prolonged low-speed operation reduces the motor load and heat generation, thereby improving system reliability and maintenance intervals.

[0036] In a preferred embodiment of the present invention, when there is no need for steering, the preset delay duration is 30 seconds.

[0037] Specifically, in actual driving, the vehicle's power signal may fluctuate briefly due to road bumps, short-term steering adjustments, or other interference factors. The 30-second delay setting can effectively filter out these brief power changes and avoid frequent switching of the oil pump speed due to misjudgment.

[0038] In a preferred embodiment of the present invention, when the steering pump motor switches from the current speed to the first preset speed, the control speed increases rapidly; when the steering pump motor switches from the current speed to the second preset speed, the control speed decreases slowly.

[0039] Specifically, when a steering request is detected, the system immediately and rapidly increases the oil pump speed to 1200 rpm, ensuring that the steering pump can quickly provide sufficient hydraulic flow and pressure to meet the driver's steering needs. This rapid response mechanism can significantly reduce the delay in power steering, improve driving safety and comfort, and avoid steering difficulties or delays caused by slow speed increases.

[0040] When no steering demand is detected, the system slowly reduces the oil pump speed to 500 rpm. This gradual deceleration mechanism avoids driving discomfort caused by excessively rapid speed reduction, such as a sudden increase in steering wheel weight (kickback), ensuring a smooth and comfortable driving experience. Gradual deceleration also reduces mechanical shock to the oil pump motor, extending equipment lifespan and improving system reliability and stability.

[0041] In a preferred embodiment of the present invention, when the steering oil pump motor switches from the current speed to the first preset speed, the speed increase rate is 400 rpm / s.

[0042] Specifically, by setting the speed increase rate to 400 rpm / s, the steering pump can quickly increase to the target speed of 1200 rpm in a short time, ensuring that the steering system can provide sufficient assistance in a timely manner when the driver performs steering operations, and avoiding steering delay or insufficient assistance caused by slow speed increase.

[0043] The 400 rpm / s acceleration rate ensures rapid response while avoiding a sharp increase in energy consumption caused by excessively rapid engine speed increases. This rate satisfies steering requirements without excessive energy consumption, thus optimizing the overall energy efficiency of the system.

[0044] In a preferred embodiment of the present invention, when the steering oil pump motor switches from the current speed to the second preset speed, the speed decrease rate is 50 rpm / s.

[0045] Specifically, by setting the speed reduction rate to 50 rpm / s, the power steering pump can slowly reduce the speed when there is no need for steering, avoiding driving discomfort caused by excessive speed reduction, such as a sudden increase in steering wheel weight (kickback), and ensuring smoothness and comfort during driving.

[0046] The 50rpm / s engine speed reduction rate ensures a smooth driving experience, reduces driver fatigue, and enhances the driving experience.

[0047] In a preferred embodiment of the present invention, in S2, the offset value is 100w.

[0048] Specifically, in actual operation, the power of the power steering pump motor may be affected by various factors, such as oil temperature changes, oil viscosity, and motor aging. By adding a 100W offset value to the calculated power value, misjudgments caused by these interference factors can be effectively avoided, reducing frequent speed switching due to misjudgments and ensuring the accuracy of the system in determining steering needs.

[0049] When the vehicle's steering wheel is in the center position, the real-time power of the power steering pump motor at 1000 rpm is 100W. By adding an offset value of 100W, the system sets the power threshold at this speed to 200W. This way, the system will only determine a steering need when the real-time power exceeds 200W, thus avoiding misjudgments caused by brief power fluctuations or environmental interference.

[0050] When the vehicle's steering wheel is in the center position, the power steering pump motor has a real-time power of 150W at 1500rpm. By adding a 100W offset value, the system sets the power threshold at this speed to 250W. Thus, the system only determines a steering need when the real-time power exceeds 250W.

[0051] When the vehicle's steering wheel is in the center position, the power steering pump motor has a real-time power of 70W at 500rpm. By adding a 100W offset value, the system sets the power threshold at this speed to 170W. Thus, the system will only determine a steering need when the real-time power exceeds 170W.

[0052] A steering oil pump control system for a new energy commercial vehicle, characterized in that it includes: The signal acquisition module collects the current, voltage, and speed of the steering oil pump motor; The control module receives the current, voltage, and speed, calculates the power of the steering pump motor when the steering wheel is in the center position, establishes a reference table of speed and power thresholds when there is no steering requirement, calculates the real-time power of the steering pump motor, and compares it with the power threshold corresponding to the current speed to determine whether the vehicle has a steering requirement. The drive module adjusts the target speed of the steering oil pump motor according to steering requirements.

[0053] Specifically, the signal acquisition module only utilizes the inherent current, voltage, and speed signals of the steering pump motor to identify steering needs, requiring no additional hardware and reducing costs and failure rates. The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for controlling a steering oil pump in a new energy commercial vehicle, characterized in that, include: S1. Adjust the speed of the steering pump motor and test the current and voltage of the steering pump motor when the vehicle steering wheel is in the center position at different speeds. S2. Based on the current and voltage detected in S1, calculate the power of the steering pump motor at different speeds, and add an offset value to each calculated power value to obtain the power threshold. Establish a reference table of speed and power threshold when there is no steering requirement. S3. Real-time acquisition of the speed, current and voltage signals of the steering pump motor, calculation of the real-time power of the steering pump motor, and comparison with the power threshold corresponding to the current speed to determine whether the vehicle has a steering requirement; S4. Adjust the target speed of the steering oil pump motor according to steering requirements.

2. The method for controlling the steering oil pump of a new energy commercial vehicle according to claim 1, characterized in that: In S3, the condition for determining whether a vehicle needs to turn is: When the real-time power of the steering pump motor is greater than the power threshold corresponding to the current speed, and the rising edge of the power is detected, it is determined that there is a steering demand. When the real-time power of the steering pump motor is less than the power threshold corresponding to the current speed, and a falling edge of the power is detected, it is determined that there is no steering demand.

3. The method for controlling the steering oil pump of a new energy commercial vehicle according to claim 1, characterized in that: In S4, when there is a steering requirement, the target speed of the steering pump is set to a first preset speed, which is greater than the current speed. When there is no steering requirement, after a preset delay, the target speed of the steering pump is set to a second preset speed, which is less than the current speed.

4. The method for controlling the steering oil pump of a new energy commercial vehicle according to claim 3, characterized in that: The first preset speed is 1200 rpm.

5. The steering oil pump control method for new energy commercial vehicles according to claim 3, characterized in that: The second preset speed is 500 rpm.

6. The steering oil pump control method for new energy commercial vehicles according to claim 3, characterized in that: When there is no need to turn, the preset delay duration is 30 seconds.

7. The steering oil pump control method for new energy commercial vehicles according to claim 3, characterized in that: When the steering pump motor switches from the current speed to the first preset speed, the control speed increases rapidly; when the steering pump motor switches from the current speed to the second preset speed, the control speed decreases slowly.

8. The steering oil pump control method for new energy commercial vehicles according to claim 3, characterized in that: When the power steering pump motor switches from the current speed to the first preset speed, the speed increase rate is 400 rpm / s; when the power steering pump motor switches from the current speed to the second preset speed, the speed decrease rate is 50 rpm / s.

9. The method for controlling the steering oil pump of a new energy commercial vehicle according to claim 1, characterized in that: In S2, the offset value is 100w.

10. A steering oil pump control system for a new energy commercial vehicle, characterized in that, include: The signal acquisition module collects the current, voltage, and speed of the steering oil pump motor; The control module receives the current, voltage, and speed, calculates the power of the steering oil pump motor when the steering wheel is in the center position, and establishes a reference table of speed and power thresholds when there is no steering requirement. Calculate the real-time power of the steering pump motor and compare it with the power threshold corresponding to the current speed to determine whether the vehicle has a steering need; The drive module adjusts the target speed of the steering oil pump motor according to steering requirements.

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