Predictive cruise and vehicle speed limit cooperative control method and device

Abstract

The invention provides a predictive cruise and vehicle speed limit cooperative control method and device, and the method comprises the steps: adjusting the upper and lower limit values of a predictive cruise vehicle speed based on the road congestion degree, road slope information and the current constant speed cruise vehicle speed, and obtaining the corrected upper and lower limit values of the predictive cruise vehicle speed, calculating a predicted braking vehicle speed based on a comparison result of the neutral coasting downhill predicted vehicle speed sequence and the coordinated vehicle speed limit value; calculating a predictive cruise vehicle speed, a predictive cruise gear and a predictive cruise gear control state based on the corrected upper and lower limit values of the predictive cruise vehicle speed and the predictive braking vehicle speed; the cruise demand torque is adjusted based on the comparison result of the actual vehicle speed and the limited vehicle speed and the predictive cruise vehicle speed, and the corrected cruise demand torque is obtained; and based on the predictive cruise mode and the corrected cruise demand torque, determining a calculation mode of the vehicle speed limit demand torque. Through the method provided by the invention, cooperative control of predictive cruise and vehicle speed limitation is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle speed control, and in particular to a predictive cruise and vehicle speed limit coordinated control method and device. Background Art

[0002] Towing vehicles with a maximum speed greater than or equal to 90km / h should be equipped with four related safety configurations, including steering wheel disc brakes, electronic braking system EBS, automatic emergency braking system AEBS, and anti-explosion tire emergency device. If the relevant safety configuration is incomplete, the vehicle will be limited to 89km / h. At present, under free driving conditions and cruise control conditions, the speed limit function uses PID to adjust the speed limit torque, and then outputs the required torque after taking the smaller of the throttle torque / cruise torque; torque jitter and engine speed jitter are prone to occur at the critical upper speed limit speed point. Given the current situation where the fuel cost of commercial vehicles accounts for a high proportion of operating costs, vehicle fuel saving control is very important. The predictive cruise control method allows the vehicle speed to fluctuate within a certain range by considering the slope information of the road ahead, and makes full use of the kinetic energy of the vehicle and the potential energy of the road, which can effectively avoid fuel-inefficient driving behavior.

[0003] At present, in the case of low-speed cruise control, when the predictive cruise is in positive torque when going uphill, there will be no interference with the speed limit torque, thus achieving fuel saving effect; in the case of low speed control, the cruise may be reversed due to the speed deviation during the uphill process; in the case of high-speed cruise control, when turning from downhill to uphill, the braking end speed is high and there will be interference with the speed limit, resulting in fuel loss. Therefore, it is very important to coordinate the control of predictive cruise and speed limit, so as to maximize fuel saving under the premise of ensuring safety. The existing technology generally simply takes the smaller of the predictive cruise demand torque and the speed limit demand torque, and then performs demand torque filtering when switching the internal torque coordination mode; there has been no research on the coordinated control of predictive cruise and speed limit.

[0004] How to achieve coordinated control of predictive cruise control and speed limit is a technical problem that needs to be solved at present. Summary of the invention

[0005] The present invention provides a predictive cruise and vehicle speed limit coordinated control method and device, which are used to solve the defects existing in the prior art.

[0006] The present invention provides a predictive cruise control and speed limit coordinated control method, comprising the following steps: The upper and lower limits of the predictive cruise speed are adjusted based on the road congestion degree, the road slope information and the current cruise speed to obtain the revised upper and lower limits of the predictive cruise speed, and the predicted braking speed is calculated based on the comparison result of the neutral gear coasting downhill predicted speed sequence and the coordinated speed limit value; Based on the corrected upper and lower limits of the predictive cruise speed and the predicted braking speed, the predictive cruise speed, the predictive cruise gear and the predictive cruise gear control state are calculated; wherein the predictive cruise gear and the predictive cruise gear control state are used to control the gear when the vehicle is cruising; Adjusting the cruise demand torque based on the comparison result between the actual vehicle speed and the speed limit and the predicted cruise speed to obtain a corrected cruise demand torque; Based on the predictive cruise mode and the corrected cruise demand torque, a calculation method of the vehicle speed limit demand torque is determined, and the vehicle speed limit demand torque is calculated according to the determined calculation method.

[0007] According to a predictive cruise and speed limit coordinated control method provided by the present invention, the predictive cruise speed upper and lower limits are adjusted based on the road congestion degree, road slope information and the current cruise speed to obtain the corrected predictive cruise speed upper and lower limits, including: The original speed limit is adjusted based on the road congestion degree, road slope and road curvature to obtain a coordinated speed limit; The minimum value between the coordinated vehicle speed limit and the predictive cruising vehicle speed upper limit is used as the corrected predictive cruising vehicle speed upper limit.

[0008] According to a predictive cruise and speed limit coordinated control method provided by the present invention, the predictive cruise speed upper and lower limits are adjusted based on the road congestion degree, road slope information and the current cruise speed to obtain the corrected predictive cruise speed upper and lower limits, including: The predictive cruise speed lower limit is adjusted based on the current cruise control speed to obtain a corrected predictive cruise speed lower limit; Wherein, when the current cruise control speed is less than a preset speed threshold, the correction coefficient corresponding to the current cruise control speed is negatively correlated with the current cruise control speed.

[0009] According to a predictive cruise control and speed limit coordinated control method provided by the present invention, the predicted braking speed is calculated based on the comparison result of the predicted vehicle speed sequence of coasting downhill in neutral gear and the coordinated vehicle speed limit value, including: If the next uphill slope is a short uphill slope with a slope length less than the preset slope length, and there is a first target position point in the predicted vehicle speed sequence for coasting downhill in neutral gear that is greater than the coordinated vehicle speed limit, the vehicle brakes at the first target position point and the actual vehicle speed remains at the coordinated vehicle speed limit, then coasting in gear is adopted for this downhill slope; or, When the next uphill slope is a long uphill slope with a slope length greater than or equal to the preset slope length, and there is a second target position point in the predicted vehicle speed sequence for coasting downhill in neutral that is greater than the sum of the coordinated vehicle speed limit plus the drift threshold, the gear is engaged and braked at the second target position point, and the actual vehicle speed is maintained at the coordinated vehicle speed limit value plus the drift threshold.

[0010] According to a predictive cruise and speed limit coordinated control method provided by the present invention, the cruise demand torque is adjusted based on the comparison result between the actual vehicle speed and the speed limit and the predictive cruise speed to obtain a corrected cruise demand torque, including: The cruise demand torque before correction is adjusted based on the cruise demand torque change rate correction coefficient and the torque correction coefficient to obtain a first demand torque, and the cruise demand torque before correction is adjusted based on the cruise demand torque change rate correction coefficient and the torque correction coefficient to obtain an intermediate demand torque, and the intermediate demand torque is added to the cruise demand torque before correction to obtain a second demand torque; determining a minimum value between the first required torque and the second required torque as a corrected cruise required torque; Among them, the cruise demand torque change rate correction coefficient is calculated based on the difference between the actual vehicle speed and the speed limit; if the difference is within the correction threshold range, the value of the cruise demand torque change rate correction coefficient is 1, otherwise, the cruise demand torque change rate correction coefficient is negatively correlated with the difference.

[0011] According to a predictive cruise control and vehicle speed limit coordinated control method provided by the present invention, the torque correction coefficient can be obtained by the following calculation method: If the actual torque and the required torque have the same rate of change, the torque correction coefficient is set to 1; otherwise, the result of adding the quotient of the actual torque and the required torque to 1 is used as the torque correction coefficient.

[0012] According to a predictive cruise and speed limit coordinated control method provided by the present invention, the calculation method of the speed limit demand torque is determined based on the predictive cruise mode and the modified cruise demand torque, and the speed limit demand torque is calculated according to the determined calculation method, including: When the predictive cruise mode is map-valid and the corrected cruise demand torque is positive, using the corrected cruise demand torque as the vehicle speed limit demand torque; or, When the predictive cruise mode is map-invalid or the vehicle is not in a cruise state, the speed limit required torque is obtained by performing PID control calculation based on the actual vehicle speed and the vehicle speed limit.

[0013] According to a predictive cruise control and speed limit coordinated control method provided by the present invention, the speed limit required torque is obtained by performing PID control calculation based on the actual speed and the speed limit, including: Calculating the product of a first correction coefficient corresponding to the driving style, a second correction coefficient corresponding to the road slope, and a third correction coefficient corresponding to the road curvature to obtain a target correction coefficient; Correcting the actual vehicle speed calculated by the PID control based on the target correction coefficient; Among them, the target correction coefficient is negatively correlated with the vehicle speed deviation value; the first correction coefficient is negatively correlated with the aggressiveness of driving; the second correction coefficient is positively correlated with the slope value of the road slope; the third correction coefficient is positively correlated with the road curvature; the vehicle speed deviation value is: the difference between the limit speed and the actual speed calculated by the PID control.

[0014] The present invention also provides a predictive cruise control and speed limit coordinated control device, comprising the following modules: The first calculation module is used to adjust the upper and lower limits of the predictive cruise speed based on the road congestion degree, the road slope information and the current cruise speed to obtain the revised upper and lower limits of the predictive cruise speed, and calculate the predicted braking speed based on the comparison result of the neutral gear coasting downhill predicted speed sequence and the coordinated speed limit value; a second calculation module, for calculating the predictive cruise speed, the predictive cruise gear, and the predictive cruise gear control state based on the corrected predictive cruise speed upper and lower limits and the predicted braking speed; wherein the predictive cruise gear and the predictive cruise gear control state are used to control the gear when the vehicle is cruising; an adjustment module, configured to adjust the cruise demand torque based on a comparison result between the actual vehicle speed and the speed limit and the predicted cruise speed, so as to obtain a corrected cruise demand torque; The third calculation module is used to determine a calculation method of the vehicle speed limit required torque based on the predictive cruise mode and the corrected cruise required torque, and calculate the vehicle speed limit required torque according to the determined calculation method.

[0015] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the predictive cruise control and vehicle speed limit collaborative control method as described in any one of the above-mentioned methods is implemented.

[0016] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the predictive cruise control and vehicle speed limit coordinated control method as described in any one of the above is implemented.

[0017] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the computer program implements any of the above-mentioned predictive cruise control and vehicle speed limit coordinated control methods.

[0018] The present invention provides a predictive cruise and speed limit coordinated control method and device, which adjusts the predictive cruise speed upper and lower limits based on the road congestion degree, road slope information and the current cruise speed to obtain revised predictive cruise speed upper and lower limits, and calculates the predicted braking speed based on the comparison result of the neutral gear coasting downhill predicted speed sequence and the coordinated speed limit value; calculates the predictive cruise speed, predictive cruise gear and predictive cruise gear control state based on the revised predictive cruise speed upper and lower limits and the predicted braking speed; wherein the predictive cruise gear and the predictive cruise gear control state are used to control the gear of the vehicle when cruising; adjusts the cruise demand torque based on the comparison result of the actual vehicle speed and the speed limit and the predictive cruise speed to obtain a revised cruise demand torque; determines the calculation method of the speed limit demand torque based on the predictive cruise mode and the revised cruise demand torque, and calculates the speed limit demand torque according to the determined calculation method. It can be seen from this that the present invention achieves coordinated control of predictive cruise and vehicle speed limit, thereby improving the fuel-saving effect of predictive cruise. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a flow chart of the predictive cruise and speed limit coordinated control method provided by the present invention.

[0021] Figure 2 It is a complete flow chart of the predictive cruise and speed limit coordinated control method provided by the present invention.

[0022] Figure 3 It is a structural schematic diagram of the predictive cruise and speed limit cooperative control device provided by the present invention.

[0023] Figure 4 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Combine the following Figure 1-Figure 4 A predictive cruise control and vehicle speed limit coordinated control method and device of the present invention are described.

[0026] It should be noted that there is no existing technology to study the coordinated control of predictive cruise and speed limit; generally, the predictive cruise demand torque and the speed limit demand torque are simply taken as the smaller one, and then the demand torque filtering is performed when the internal torque coordination mode is switched. The current technical solution has the following shortcomings: 1) There is interference between the maximum speed calculation torque in predictive cruise and the traditional speed limit calculation torque, resulting in engine speed jitter; 2) The predictive cruise downhill braking torque calculation does not take into account the next uphill speed limit, resulting in exceeding the speed limit and engine speed jitter; 3) The predictive cruise maximum speed limit does not take into account the influence of driver style; 4) The predictive cruise maximum speed limit does not take into account the influence of road congestion; 5) The lower limit of the predictive cruise speed is a single calibration value during low-speed cruise, and different models will experience cruise deceleration. Based on this, the present invention provides a predictive cruise and speed limit coordinated control method to solve at least one of the above problems.

[0027] Figure 1 is a flow chart of the predictive cruise control and speed limit coordinated control method provided by the present invention, such as Figure 1 As shown, the method includes the following: Step 100: Adjust the upper and lower limits of the predictive cruise speed based on the road congestion level, road slope information and the current cruise speed to obtain revised upper and lower limits of the predictive cruise speed, and calculate the predicted braking speed based on the comparison result of the neutral gear coasting downhill predicted speed sequence and the coordinated speed limit value.

[0028] Figure 2 This is a complete flow chart of the predictive cruise and speed limit coordinated control method provided by the present invention. Figure 2 The predictive cruise control and speed limit coordinated control method provided by the present invention is fully described.

[0029] Specifically, step 100 adjusts the upper and lower limits of the predictive cruise speed based on the road congestion degree, the road slope information and the current cruise speed to obtain the corrected upper and lower limits of the predictive cruise speed, including: Step 110: Adjust the original vehicle speed limit based on the road congestion level, road slope, and road curvature to obtain a coordinated vehicle speed limit.

[0030] Step 120: The minimum value between the coordinated vehicle speed limit and the predictive cruise vehicle speed upper limit is used as the corrected predictive cruise vehicle speed upper limit.

[0031] Step 130: adjusting the predictive cruise speed lower limit based on the current cruise speed to obtain a corrected predictive cruise speed lower limit; Wherein, when the current cruise control speed is less than a preset speed threshold, the correction coefficient corresponding to the current cruise control speed is negatively correlated with the current cruise control speed.

[0032] In one embodiment, the calculation method of the coordinated vehicle speed limit and the coordinated vehicle speed upper and lower limits is described.

[0033] The coordinated speed limit is calculated according to the following formula: in, Indicates coordinated speed limit. Indicates the original speed limit.

[0034] Indicates the speed limit correction coefficient based on the driver's style. When the driver's style is mild and cautious, the speed limit correction coefficient is 1, that is, the default calibration is mild and cautious. When the driver's style is aggressive, the speed limit correction coefficient increases according to the aggressiveness of the driver's style, and the actual speed and speed limit deviation threshold decreases according to the aggressiveness of the driver's style. That is, when the driver's style is aggressive, the actual speed is allowed to be closer to the speed limit.

[0035] It indicates the speed limit correction coefficient according to the road congestion degree and slope judgment; when the road congestion degree is congestion, the speed limit correction coefficient according to the road congestion degree and slope is 1, that is, the default calibration is calibrated according to the serious road congestion, and the speed limit is not corrected to ensure safety; when the road congestion degree is unobstructed and the slope is judged to be uphill, the speed limit correction coefficient according to the road congestion degree and slope increases with the slope, and the actual speed and speed limit deviation threshold decreases as the slope increases. That is, in predictive cruising, the higher the degree of the actual speed close to the speed limit in the uphill condition, the higher the actual speed is allowed to be; the reason is that the required cruising speed in the uphill stage of predictive cruising is a downward trend.

[0036] Indicates the speed limit correction coefficient based on the curvature of the road congestion degree. When the road congestion degree is congestion, the speed limit correction coefficient based on the curvature of the road congestion degree is 1, that is, the default calibration is based on the serious road congestion, and the speed limit is not corrected to ensure safety. When the road congestion degree is unobstructed and the curvature is judged as a turn, the speed limit correction coefficient based on the curvature of the road congestion degree decreases with the curvature, and the deviation threshold between the actual speed and the speed limit increases as the curvature increases. That is, in predictive cruising, when the road is unobstructed, the lower the degree to which the actual speed is close to the speed limit, the lower the degree to which the actual speed is allowed to be in the turning condition.

[0037] The upper and lower limits of coordinated vehicle speed are calculated according to the following formula: in, Represents the corrected predictive cruise speed upper limit value; obtained by taking the smaller of the predictive cruise speed upper limit value before correction and the corrected speed limit. Indicates the upper limit of predictive cruise speed before correction. Indicates the revised speed limit.

[0038] in, It represents the corrected predictive cruise speed lower limit value; it is obtained by multiplying the predictive cruise speed lower limit value before correction by the speed lower limit correction coefficient based on the cruise speed. Indicates the lower limit of predictive cruise control speed before correction. Indicates the speed lower limit correction coefficient based on the cruise control speed; when the cruise control speed is lower than the threshold, the speed lower limit correction coefficient of the cruise control speed correction gradually increases, with the aim of increasing the predictive cruise control speed lower limit value and avoiding frequent cruise control exits when different vehicle models match low cruise control speeds.

[0039] Specifically, step 100 calculates the predicted braking vehicle speed based on the comparison result of the neutral gear coasting downhill predicted vehicle speed sequence and the coordinated vehicle speed limit value, including: If the next uphill slope is a short uphill slope with a slope length less than the preset slope length, and there is a first target position point in the predicted vehicle speed sequence for coasting downhill in neutral gear that is greater than the coordinated vehicle speed limit, the vehicle brakes at the first target position point and the actual vehicle speed remains at the coordinated vehicle speed limit, then coasting in gear is adopted for this downhill slope; or, When the next uphill slope is a long uphill slope with a slope length greater than or equal to the preset slope length, and there is a second target position point in the predicted vehicle speed sequence for coasting downhill in neutral that is greater than the sum of the coordinated vehicle speed limit plus the drift threshold, the gear is engaged and braked at the second target position point, and the actual vehicle speed is maintained at the coordinated vehicle speed limit value plus the drift threshold.

[0040] Furthermore, the calculation method of the predicted braking vehicle speed is described.

[0041] 1) Calculate the predicted vehicle speed sequence {v1, v2, v3, ..., vn} for coasting downhill in neutral gear; the predicted vehicle speed sequence for coasting downhill in neutral gear is calculated according to the vehicle dynamics formula.

[0042] When the next uphill slope is a short uphill slope and the predicted vehicle speed sequence {v1, v2, v3, ..., vn} for coasting downhill in neutral gear has a position point that is greater than the coordinated vehicle speed limit, then the gear is engaged and the vehicle brake is applied at that position point to keep the actual vehicle speed at the coordinated vehicle speed limit value. In this case, coasting in gear is adopted for this downhill slope.

[0043] When coasting in gear, the downhill predicted vehicle speed sequence {v1, v2, v3, ..., vn} is calculated according to the vehicle dynamics formula for coasting in gear to obtain {v11, v21, v31, ..., vn1}.

[0044] 2) If the next uphill slope is a long uphill slope and the predicted vehicle speed sequence {v1, v2, v3, ..., vn} of coasting downhill in neutral gear has a position point that is greater than the coordinated vehicle speed limit plus the drift threshold, then the gear is engaged and braked at this position point to keep the actual vehicle speed at the coordinated vehicle speed limit plus the drift threshold; It should be noted that the upward drift threshold refers to the speed value of the speed limit after coordination. Because the next uphill is a long uphill and the predicted speed sequence {v1, v2, v3, ..., vn} of coasting downhill in neutral gear has a position point greater than the speed limit after coordination plus the drift threshold, it means that the next uphill is a long uphill and coasting in gear, then the speed limit can be appropriately released, and the speed should not be restricted before the next long uphill, so as to convert all the downhill kinetic energy into the potential energy of the next uphill. The speed limit after coordination plus the drift threshold should be less than the maximum speed under the braking capacity of the downhill vehicle. The maximum speed under the braking capacity of the downhill vehicle is the maximum speed at which the vehicle can be stable when the brake fluid in the cylinder and the braking capacity are working according to the vehicle configuration.

[0045] It should be noted that the above steps are calculated when the road congestion level is not congested; when the road congestion level is congested, downhill braking adopts in-gear gliding and reminds the driver to pay attention to the road conditions and brake in time to exit cruise.

[0046] Step 200: Calculate the predictive cruise speed, the predictive cruise gear, and the predictive cruise gear control state based on the corrected predictive cruise speed upper and lower limits and the predicted braking speed; wherein the predictive cruise gear and the predictive cruise gear control state are used to control the gear of the vehicle when cruising.

[0047] Specifically, the predictive cruise speed, the predictive cruise gear, and the predictive cruise gear control state are calculated by the model predictive control method.

[0048] Step 300: adjusting the cruise demand torque based on the comparison result between the actual vehicle speed and the speed limit and the predicted cruise speed to obtain a corrected cruise demand torque.

[0049] Specifically, step 300 includes: Step 310, adjusting the cruise demand torque before correction based on the cruise demand torque change rate correction coefficient and the torque correction coefficient to obtain a first demand torque, and adjusting the cruise demand torque before correction based on the cruise demand torque change rate correction coefficient and the torque correction coefficient to obtain an intermediate demand torque, and adding the intermediate demand torque to the cruise demand torque before correction to obtain a second demand torque.

[0050] Step 320: Determine the minimum value of the first required torque and the second required torque as the corrected cruise required torque; Among them, the cruise demand torque change rate correction coefficient is calculated based on the difference between the actual vehicle speed and the speed limit; if the difference is within the correction threshold range, the value of the cruise demand torque change rate correction coefficient is 1, otherwise, the cruise demand torque change rate correction coefficient is negatively correlated with the difference.

[0051] In one embodiment, a method for calculating the cruise demand torque is described.

[0052] The cruise demand torque is calculated according to the following formula: in, It represents the corrected cruise demand torque; Indicates the cruise demand torque before correction.

[0053] Indicates the cruise demand torque change rate correction coefficient, which is calculated based on the difference between the actual vehicle speed and the speed limit. When the difference between the actual vehicle speed and the speed limit is outside the correction threshold range, the cruise demand torque change rate correction coefficient is 1 and no correction is required. When the difference between the actual vehicle speed and the speed limit is within the correction threshold range, the cruise demand torque change rate correction coefficient is the opposite direction of the difference between the actual vehicle speed and the speed limit. That is, the smaller the difference between the actual vehicle speed and the speed limit, the larger the cruise demand torque change rate correction coefficient is, to avoid exceeding the speed limit and causing the engine speed to fluctuate.

[0054] Indicates the torque correction coefficient of cruise demand torque obtained according to actual torque. When the actual torque and demand torque change rate are consistent, the torque correction coefficient is 1 and no correction is made; when the actual torque and demand torque change rate are inconsistent, the torque correction coefficient is calculated as follows: Step 400: Based on the predictive cruise mode and the corrected cruise demand torque, determine a calculation method for the vehicle speed limit demand torque, and calculate the vehicle speed limit demand torque according to the determined calculation method.

[0055] Specifically, step 400 includes: Step 410: When the predictive cruise mode is map-valid and the corrected cruise demand torque is positive, use the corrected cruise demand torque as the vehicle speed limit demand torque; or, Step 420: When the predictive cruise mode is in a map-invalid state or the vehicle is not in a cruise state, a PID control calculation is performed based on the actual vehicle speed and the vehicle speed limit to obtain the vehicle speed limit required torque.

[0056] Step 420 specifically includes: Step 421: Calculate the product of a first correction coefficient corresponding to the driving style, a second correction coefficient corresponding to the road slope, and a third correction coefficient corresponding to the road curvature to obtain a target correction coefficient.

[0057] Step 422: correcting the actual vehicle speed calculated by the PID control based on the target correction coefficient; Among them, the target correction coefficient is negatively correlated with the vehicle speed deviation value; the first correction coefficient is negatively correlated with the aggressiveness of driving; the second correction coefficient is positively correlated with the slope value of the road slope; the third correction coefficient is positively correlated with the road curvature; the vehicle speed deviation value is: the difference between the limit speed and the actual speed calculated by the PID control.

[0058] In one embodiment, a method for calculating the vehicle speed limit required torque is described.

[0059] The speed limit required torque is selected as follows: When the predictive cruise mode is in map validity and the cruise demand torque is positive, the speed limit demand torque selects the cruise demand torque; when the predictive cruise mode is in map invalid or not cruising, the speed limit demand torque is obtained by adaptive PID control calculation based on the actual vehicle speed and the speed limit.

[0060] According to the actual vehicle speed and the speed limit, the adaptive PID torque control modifies the PID coefficient and threshold according to the following formula: It indicates the correction coefficient of the PID coefficient and threshold value for calculating the speed limit torque according to the driver's style. When the driver's style is mild and cautious, the correction coefficient of the PID coefficient and threshold value for calculating the speed limit torque according to the driver's style is 1, that is, the default calibration is calibrated according to the mild and cautious type. When the driver's style is aggressive, the correction coefficient of the PID change coefficient for calculating the speed limit torque is reduced according to the aggressiveness of the driver's style, and the correction coefficient of the deviation threshold between the actual vehicle speed and the speed limit is reduced according to the aggressiveness of the driver's style. That is, when the driver's style is aggressive, the higher the degree to which the actual vehicle speed is allowed to approach the speed limit; it is worth noting that the correction coefficient cannot make the actual vehicle speed exceed the upper limit of the allowable deviation of the speed limit.

[0061] Indicates the correction coefficient of the PID coefficient and threshold value for calculating the speed limit torque according to the slope; when the current road and the future road are judged as flat roads, the correction coefficient of the PID coefficient and threshold value for calculating the speed limit torque according to the slope is 1, that is, the default calibration is set according to the flat road; when the current road and the future road are judged as uphill, the correction coefficient of the PID change coefficient for calculating the speed limit torque decreases as the slope increases, and the correction coefficient of the actual speed and the speed limit deviation threshold decreases as the slope increases. That is, the greater the slope, the higher the degree to which the actual speed is allowed to approach the speed limit.

[0062] Indicates the correction coefficient of the PID coefficient and threshold value for calculating the speed limit torque according to the curvature; when the curvature of the current road and the future road is judged as a straight road type, the correction coefficient of the PID coefficient and threshold value for calculating the speed limit torque according to the slope is 1, that is, the default calibration is set according to the straight road type; when the curvature of the current road and the future road is judged as a curved road type, the correction coefficient of the PID change coefficient for calculating the speed limit torque increases as the curvature increases, and the correction coefficient of the actual speed and the speed limit deviation threshold increases as the curvature increases. That is, the greater the curvature, the lower the degree to which the actual speed is allowed to approach the speed limit.

[0063] The predictive cruise control and speed limit coordinated control method provided by the present invention takes the smaller of the upper speed limit and the speed limit when calculating the upper and lower speed limits after coordination, thereby reducing unnecessary speed limits and improving the fuel saving effect of predictive cruise control; when calculating the upper and lower speed limits after coordination, the lower speed limit of predictive cruise control is dynamically calculated during low-speed cruise control to avoid frequent cruise control failure caused by matching different vehicle models; when calculating the speed limit after coordination, the influence of the driver's style and the degree of road congestion are considered, and the speed limit threshold allowable deviation threshold is narrowed for aggressive drivers and when there is no congestion ahead and in the uphill stage, thereby improving predictive cruise control. Cruise fuel-saving effect; when calculating the predicted braking speed, the downhill braking speed threshold refers to the next uphill map information and the speed limit calculation to avoid exceeding the speed limit and thus causing engine speed jitter; when calculating the cruise demand torque, the cruise torque control controls the demand torque change rate based on the difference between the actual speed and the speed limit to avoid exceeding the speed limit and thus causing engine speed jitter; in the free driving condition, the speed limit torque increases the driver's style, slope, and curvature to correct the PID parameters, and the speed limit torque control is adaptive to the driver's style and roads with different slopes and curvatures, reducing the calibration workload.

[0064] The above is a description of the steps of the predictive cruise and speed limit coordinated control method provided by the present invention. From the description of the above steps, it can be seen that according to the predictive cruise and speed limit coordinated control method provided by the present invention, the predictive cruise speed upper and lower limits are adjusted based on the road congestion degree, road slope information and the current cruise speed to obtain the revised predictive cruise speed upper and lower limits, and the predicted braking speed is calculated based on the comparison result of the neutral gear coasting downhill predicted speed sequence and the coordinated speed limit value; based on the revised predictive cruise speed upper and lower limits and the predicted braking speed, the predictive cruise speed, the predictive cruise gear and the predictive cruise gear control state are calculated; wherein the predictive cruise gear and the predictive cruise gear control state are used to control the gear when the vehicle is cruising; based on the comparison result of the actual speed and the speed limit and the predictive cruise speed, the cruise demand torque is adjusted to obtain the revised cruise demand torque; based on the predictive cruise mode and the revised cruise demand torque, the calculation method of the speed limit demand torque is determined, and the speed limit demand torque is calculated according to the determined calculation method. It can be seen from this that the present invention achieves coordinated control of predictive cruise and vehicle speed limit, thereby improving the fuel-saving effect of predictive cruise.

[0065] The predictive cruise control and vehicle speed limit coordinated control device provided by the present invention is described below. The predictive cruise control and vehicle speed limit coordinated control device described below and the predictive cruise control and vehicle speed limit coordinated control method described above can be referred to each other.

[0066] Figure 3is a schematic diagram of the structure of the predictive cruise and speed limit coordinated control device provided by the present invention, such as Figure 3 As shown, the predictive cruise control and speed limit coordinated control device provided by the present invention includes: The first calculation module 301 is used to adjust the upper and lower limits of the predictive cruise speed based on the road congestion degree, the road slope information and the current cruise speed to obtain the revised upper and lower limits of the predictive cruise speed, and calculate the predicted braking speed based on the comparison result of the neutral coasting downhill predicted speed sequence and the coordinated speed limit value; A second calculation module 302 is used to calculate the predictive cruise speed, the predictive cruise gear and the predictive cruise gear control state based on the corrected predictive cruise speed upper and lower limits and the predicted braking speed; wherein the predictive cruise gear and the predictive cruise gear control state are used to control the gear when the vehicle is cruising; An adjustment module 303, configured to adjust the cruise demand torque based on the comparison result between the actual vehicle speed and the speed limit and the predicted cruise speed to obtain a corrected cruise demand torque; The third calculation module 304 is used to determine a calculation method of the vehicle speed limit required torque based on the predictive cruise mode and the corrected cruise required torque, and calculate the vehicle speed limit required torque according to the determined calculation method.

[0067] The predictive cruise and speed limit coordinated control device provided by the present invention adjusts the predictive cruise speed upper and lower limits based on the road congestion degree, road slope information and the current cruise speed to obtain the revised predictive cruise speed upper and lower limits, and calculates the predicted braking speed based on the comparison result of the neutral gear coasting downhill predicted speed sequence and the coordinated speed limit value; calculates the predictive cruise speed, predictive cruise gear and predictive cruise gear control state based on the revised predictive cruise speed upper and lower limits and the predicted braking speed; wherein the predictive cruise gear and the predictive cruise gear control state are used to control the gear when the vehicle is cruising; adjusts the cruise demand torque based on the comparison result between the actual speed and the speed limit and the predictive cruise speed to obtain the revised cruise demand torque; determines the calculation method of the speed limit demand torque based on the predictive cruise mode and the revised cruise demand torque, and calculates the speed limit demand torque according to the determined calculation method. It can be seen that the present invention realizes the coordinated control of predictive cruise and speed limit, and improves the fuel saving effect of predictive cruise.

[0068] Based on the above embodiment, in this embodiment, the first calculation module 301 is specifically used for: The original speed limit is adjusted based on the road congestion degree, road slope and road curvature to obtain a coordinated speed limit; The minimum value between the coordinated vehicle speed limit and the predictive cruising vehicle speed upper limit is used as the corrected predictive cruising vehicle speed upper limit.

[0069] Based on the above embodiment, in this embodiment, the first calculation module 301 is specifically used for: The predictive cruise speed lower limit is adjusted based on the current cruise control speed to obtain a corrected predictive cruise speed lower limit; Wherein, when the current cruise control speed is less than a preset speed threshold, the correction coefficient corresponding to the current cruise control speed is negatively correlated with the current cruise control speed.

[0070] Based on the above embodiment, in this embodiment, the first calculation module 301 is specifically used for: If the next uphill slope is a short uphill slope with a slope length less than the preset slope length, and there is a first target position point in the predicted vehicle speed sequence for coasting downhill in neutral gear that is greater than the coordinated vehicle speed limit, the vehicle brakes at the first target position point and the actual vehicle speed remains at the coordinated vehicle speed limit, then coasting in gear is adopted for this downhill slope; or, When the next uphill slope is a long uphill slope with a slope length greater than or equal to the preset slope length, and there is a second target position point in the predicted vehicle speed sequence for coasting downhill in neutral that is greater than the sum of the coordinated vehicle speed limit plus the drift threshold, the gear is engaged and braked at the second target position point, and the actual vehicle speed is maintained at the coordinated vehicle speed limit value plus the drift threshold.

[0071] Based on the above embodiment, in this embodiment, the adjustment module 303 is specifically used for: The cruise demand torque before correction is adjusted based on the cruise demand torque change rate correction coefficient and the torque correction coefficient to obtain a first demand torque, and the cruise demand torque before correction is adjusted based on the cruise demand torque change rate correction coefficient and the torque correction coefficient to obtain an intermediate demand torque, and the intermediate demand torque is added to the cruise demand torque before correction to obtain a second demand torque; determining a minimum value between the first required torque and the second required torque as a corrected cruise required torque; Among them, the cruise demand torque change rate correction coefficient is calculated based on the difference between the actual vehicle speed and the speed limit; if the difference is within the correction threshold range, the value of the cruise demand torque change rate correction coefficient is 1, otherwise, the cruise demand torque change rate correction coefficient is negatively correlated with the difference.

[0072] Based on the above embodiment, in this embodiment, the torque correction coefficient can be obtained by the following calculation method: If the actual torque and the required torque have the same rate of change, the torque correction coefficient is set to 1; otherwise, the result of adding the quotient of the actual torque and the required torque to 1 is used as the torque correction coefficient.

[0073] Based on the above embodiment, in this embodiment, the third calculation module 304 is specifically used for: When the predictive cruise mode is map-valid and the corrected cruise demand torque is positive, using the corrected cruise demand torque as the vehicle speed limit demand torque; or, When the predictive cruise mode is map-invalid or the vehicle is not in a cruise state, the speed limit required torque is obtained by performing PID control calculation based on the actual vehicle speed and the vehicle speed limit.

[0074] Based on the above embodiment, in this embodiment, the third calculation module 304 is specifically used for: Calculating the product of a first correction coefficient corresponding to the driving style, a second correction coefficient corresponding to the road slope, and a third correction coefficient corresponding to the road curvature to obtain a target correction coefficient; Correcting the actual vehicle speed calculated by the PID control based on the target correction coefficient; Among them, the target correction coefficient is negatively correlated with the vehicle speed deviation value; the first correction coefficient is negatively correlated with the aggressiveness of driving; the second correction coefficient is positively correlated with the slope value of the road slope; the third correction coefficient is positively correlated with the road curvature; the vehicle speed deviation value is: the difference between the limit speed and the actual speed calculated by the PID control.

[0075] Figure 4 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 4 As shown, the electronic device may be a robot or other electronic device, and the electronic device may include: a processor 410, a communications interface 420, a memory 430, and a communication bus 440, wherein the processor 410, the communications interface 420, and the memory 430 communicate with each other through the communication bus 440. The processor 410 may call the logic instructions in the memory 630 to execute the predictive cruise control and speed limit coordinated control method, including: The upper and lower limits of the predictive cruise speed are adjusted based on the road congestion degree, the road slope information and the current cruise speed to obtain the revised upper and lower limits of the predictive cruise speed, and the predicted braking speed is calculated based on the comparison result of the neutral gear coasting downhill predicted speed sequence and the coordinated speed limit value; Based on the corrected upper and lower limits of the predictive cruise speed and the predicted braking speed, the predictive cruise speed, the predictive cruise gear and the predictive cruise gear control state are calculated; wherein the predictive cruise gear and the predictive cruise gear control state are used to control the gear when the vehicle is cruising; Adjusting the cruise demand torque based on the comparison result between the actual vehicle speed and the speed limit and the predicted cruise speed to obtain a corrected cruise demand torque; Based on the predictive cruise mode and the corrected cruise demand torque, a calculation method of the vehicle speed limit demand torque is determined, and the vehicle speed limit demand torque is calculated according to the determined calculation method.

[0076] In addition, the logic instructions in the above-mentioned memory 430 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0077] On the other hand, the present invention further provides a computer program product, the computer program product comprising a computer program, the computer program can be stored in a non-transitory computer-readable storage medium, when the computer program is executed by a processor, the computer can execute the predictive cruise and speed limit coordinated control method provided by the above methods, including: The upper and lower limits of the predictive cruise speed are adjusted based on the road congestion degree, the road slope information and the current cruise speed to obtain the revised upper and lower limits of the predictive cruise speed, and the predicted braking speed is calculated based on the comparison result of the neutral gear coasting downhill predicted speed sequence and the coordinated speed limit value; Based on the corrected upper and lower limits of the predictive cruise speed and the predicted braking speed, the predictive cruise speed, the predictive cruise gear and the predictive cruise gear control state are calculated; wherein the predictive cruise gear and the predictive cruise gear control state are used to control the gear when the vehicle is cruising; Adjusting the cruise demand torque based on the comparison result between the actual vehicle speed and the speed limit and the predicted cruise speed to obtain a corrected cruise demand torque; Based on the predictive cruise mode and the corrected cruise demand torque, a calculation method of the vehicle speed limit demand torque is determined, and the vehicle speed limit demand torque is calculated according to the determined calculation method.

[0078] In another aspect, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, which is implemented when the computer program is executed by a processor to execute the predictive cruise control and vehicle speed limit coordinated control method provided by the above methods, including: The upper and lower limits of the predictive cruise speed are adjusted based on the road congestion degree, the road slope information and the current cruise speed to obtain the revised upper and lower limits of the predictive cruise speed, and the predicted braking speed is calculated based on the comparison result of the neutral gear coasting downhill predicted speed sequence and the coordinated speed limit value; Based on the corrected upper and lower limits of the predictive cruise speed and the predicted braking speed, the predictive cruise speed, the predictive cruise gear and the predictive cruise gear control state are calculated; wherein the predictive cruise gear and the predictive cruise gear control state are used to control the gear when the vehicle is cruising; Adjusting the cruise demand torque based on the comparison result between the actual vehicle speed and the speed limit and the predicted cruise speed to obtain a corrected cruise demand torque; Based on the predictive cruise mode and the corrected cruise demand torque, a calculation method of the vehicle speed limit demand torque is determined, and the vehicle speed limit demand torque is calculated according to the determined calculation method.

[0079] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0080] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0081] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A predictive cruise control and speed limit coordinated control method, characterized in that: include: The upper and lower limits of the predictive cruise speed are adjusted based on the road congestion degree, the road slope information and the current cruise speed to obtain the revised upper and lower limits of the predictive cruise speed, and the predicted braking speed is calculated based on the comparison result of the neutral gear coasting downhill predicted speed sequence and the coordinated speed limit value; Based on the corrected upper and lower limits of the predictive cruise speed and the predicted braking speed, the predictive cruise speed, the predictive cruise gear and the predictive cruise gear control state are calculated; wherein the predictive cruise gear and the predictive cruise gear control state are used to control the gear when the vehicle is cruising; Adjusting the cruise demand torque based on the comparison result between the actual vehicle speed and the speed limit and the predicted cruise speed to obtain a corrected cruise demand torque; Based on the predictive cruise mode and the corrected cruise demand torque, a calculation method of the vehicle speed limit demand torque is determined, and the vehicle speed limit demand torque is calculated according to the determined calculation method.

2. The predictive cruise control and speed limit coordinated control method according to claim 1, characterized in that: The method of adjusting the upper and lower limits of the predictive cruise speed based on the road congestion degree, the road slope information and the current cruise speed to obtain the corrected upper and lower limits of the predictive cruise speed includes: The original speed limit is adjusted based on the road congestion degree, road slope and road curvature to obtain a coordinated speed limit; The minimum value between the coordinated vehicle speed limit and the predictive cruising vehicle speed upper limit is used as the corrected predictive cruising vehicle speed upper limit.

3. The predictive cruise control and speed limit coordinated control method according to claim 1, characterized in that: The method of adjusting the upper and lower limits of the predictive cruise speed based on the road congestion degree, the road slope information and the current cruise speed to obtain the corrected upper and lower limits of the predictive cruise speed includes: The predictive cruise speed lower limit is adjusted based on the current cruise control speed to obtain a corrected predictive cruise speed lower limit; Wherein, when the current cruise control speed is less than a preset speed threshold, the correction coefficient corresponding to the current cruise control speed is negatively correlated with the current cruise control speed.

4. The predictive cruise control and speed limit coordinated control method according to claim 1, characterized in that: The method of calculating the predicted braking speed based on the comparison result of the neutral gear coasting downhill predicted vehicle speed sequence and the coordinated vehicle speed limit value comprises: If the next uphill slope is a short uphill slope with a slope length less than the preset slope length, and there is a first target position point in the predicted vehicle speed sequence for coasting downhill in neutral gear that is greater than the coordinated vehicle speed limit, the vehicle brakes at the first target position point and the actual vehicle speed remains at the coordinated vehicle speed limit, then coasting in gear is adopted for this downhill slope; or, When the next uphill slope is a long uphill slope with a slope length greater than or equal to the preset slope length, and there is a second target position point in the predicted vehicle speed sequence for coasting downhill in neutral that is greater than the sum of the coordinated vehicle speed limit plus the drift threshold, the gear is engaged and braked at the second target position point, and the actual vehicle speed is maintained at the coordinated vehicle speed limit value plus the drift threshold.

5. The predictive cruise control and speed limit coordinated control method according to claim 1, characterized in that: The adjusting the cruise demand torque based on the comparison result between the actual vehicle speed and the speed limit and the predicted cruise speed to obtain a corrected cruise demand torque includes: The cruise demand torque before correction is adjusted based on the cruise demand torque change rate correction coefficient and the torque correction coefficient to obtain a first demand torque, and the cruise demand torque before correction is adjusted based on the cruise demand torque change rate correction coefficient and the torque correction coefficient to obtain an intermediate demand torque, and the intermediate demand torque is added to the cruise demand torque before correction to obtain a second demand torque; determining a minimum value between the first required torque and the second required torque as a corrected cruise required torque; Among them, the cruise demand torque change rate correction coefficient is calculated based on the difference between the actual vehicle speed and the speed limit; if the difference is within the correction threshold range, the value of the cruise demand torque change rate correction coefficient is 1, otherwise, the cruise demand torque change rate correction coefficient is negatively correlated with the difference.

6. The predictive cruise control and speed limit coordinated control method according to claim 5, characterized in that: The torque correction coefficient can be obtained by the following calculation method: If the actual torque and the required torque have the same rate of change, the torque correction coefficient is set to 1; otherwise, the result of adding the quotient of the actual torque and the required torque to 1 is used as the torque correction coefficient.

7. The predictive cruise control and speed limit coordinated control method according to claim 1, characterized in that: The method of calculating the vehicle speed limit required torque based on the predictive cruise mode and the corrected cruise required torque, and calculating the vehicle speed limit required torque according to the determined calculation method, includes: When the predictive cruise mode is map-valid and the corrected cruise demand torque is positive, using the corrected cruise demand torque as the vehicle speed limit demand torque; or, When the predictive cruise mode is map-invalid or the vehicle is not in a cruise state, the speed limit required torque is obtained by performing PID control calculation based on the actual vehicle speed and the vehicle speed limit.

8. The predictive cruise control and speed limit coordinated control method according to claim 7, characterized in that: The PID control calculation based on the actual vehicle speed and the vehicle speed limit to obtain the vehicle speed limit required torque includes: Calculating the product of a first correction coefficient corresponding to the driving style, a second correction coefficient corresponding to the road slope, and a third correction coefficient corresponding to the road curvature to obtain a target correction coefficient; Correcting the actual vehicle speed calculated by the PID control based on the target correction coefficient; Among them, the target correction coefficient is negatively correlated with the vehicle speed deviation value; the first correction coefficient is negatively correlated with the aggressiveness of driving; the second correction coefficient is positively correlated with the slope value of the road slope; the third correction coefficient is positively correlated with the road curvature; the vehicle speed deviation value is: the difference between the limit speed and the actual speed calculated by the PID control.

9. A predictive cruise control and speed limit coordinated control device, characterized in that: include: The first calculation module is used to adjust the upper and lower limits of the predictive cruise speed based on the road congestion degree, the road slope information and the current cruise speed to obtain the revised upper and lower limits of the predictive cruise speed, and calculate the predicted braking speed based on the comparison result of the neutral gear coasting downhill predicted speed sequence and the coordinated speed limit value; a second calculation module, for calculating the predictive cruise speed, the predictive cruise gear, and the predictive cruise gear control state based on the corrected predictive cruise speed upper and lower limits and the predicted braking speed; wherein the predictive cruise gear and the predictive cruise gear control state are used to control the gear when the vehicle is cruising; an adjustment module, configured to adjust the cruise demand torque based on a comparison result between the actual vehicle speed and the speed limit and the predicted cruise speed to obtain a corrected cruise demand torque; The third calculation module is used to determine a calculation method of the vehicle speed limit required torque based on the predictive cruise mode and the corrected cruise required torque, and calculate the vehicle speed limit required torque according to the determined calculation method.

10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the predictive cruise control and vehicle speed limit coordinated control method as described in any one of claims 1 to 8 is implemented.

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