Hybrid tractor target torque, self-adaptive control method, control unit and system

Abstract

The invention discloses a target torque of a hybrid tractor, a self-adaptive control method, a control unit and a system. The target torque control method of the hybrid tractor comprises the following steps: receiving vehicle speed information within a period of time; according to the vehicle speed information, the vehicle speed change rate and the number of times of a vehicle speed change counter are determined; in response to the fact that the vehicle speed change rate and the number of times of the vehicle speed change counter meet a preset condition, accelerator opening degree information and the whole vehicle state in a whole vehicle controller are obtained; determining a to-be-optimized target torque according to the whole vehicle state; determining a constant corresponding to a weakened or enhanced driving coefficient in a table look-up mode according to preset conditions met by the accelerator opening information, the vehicle speed change rate and the number of times of a vehicle speed change counter, and determining the driving coefficient according to the constant corresponding to the driving coefficient; and determining the target torque according to the to-be-optimized target torque and the driving coefficient. The energy application efficiency can be improved without additionally arranging parts.

Description

Technical Field

[0001] The present invention belongs to the technical field of hybrid tractor control, and in particular relates to a hybrid tractor target torque, an adaptive control method, a control unit and a system. Background Art

[0002] Tractors are important agricultural production equipment. There are many working scenarios according to actual agricultural production. Different agricultural implements need to be installed to perform related working conditions. The load varies greatly during actual work. Traditional tractors are powered by diesel engines, which may cause incomplete combustion, unstable exhaust emissions, and low energy efficiency under variable loads. With the development of the domestic new energy vehicle industry, new power systems are constantly emerging. The development of new energy tractors has promoted the continuous iteration and optimization of vehicle performance and energy consumption algorithms.

[0003] For new energy tractors, how to improve energy efficiency without affecting the driving experience has become a topic. In this regard, the existing method is to add additional components, such as positioning systems, RFID, ADAS, etc. However, adding additional components will inevitably increase costs. Summary of the invention

[0004] In order to solve the problem of increasing costs by using additional components when improving energy utilization efficiency without affecting driving experience, the present invention proposes a hybrid tractor target torque, an adaptive control method, a control unit and a system.

[0005] The objective of the present invention is achieved through the following technical solutions: A first aspect of the present invention discloses a hybrid tractor target torque control method, comprising the following steps: Receive vehicle speed information within a period of time; determining a vehicle speed change rate and a number of vehicle speed change counters according to the vehicle speed information; In response to the vehicle speed change rate and the number of times of the vehicle speed change counter satisfying a preset condition, acquiring throttle opening information and vehicle status in the vehicle controller; Determining a target torque to be optimized according to the vehicle state; Determine a constant corresponding to the weakened or enhanced driving coefficient by looking up a table according to the preset conditions satisfied by the throttle opening information, the vehicle speed change rate and the number of times of the vehicle speed change counter, and determine the driving coefficient according to the constant corresponding to the driving coefficient; The target torque is determined according to the target torque to be optimized and the driving coefficient.

[0006] A second aspect of the present invention discloses a hybrid tractor adaptive control method, comprising the hybrid tractor target torque control method described in the first aspect, The acquisition of throttle opening information also includes: Obtain the target discharge power and actual power of the range extender; Calculating the difference between the actual discharge power of the range extender and its corresponding target power; In response to the vehicle speed change rate and the number of times of the vehicle speed change counter satisfying the preset condition as condition A, the increased power generation power beat power is determined by looking up a table according to condition A and the difference; In response to the preset condition that the vehicle speed change rate and the number of times of the vehicle speed change counter meet the condition B, the weakened power generation power beat power is determined by looking up the table according to the condition B and the difference.

[0007] A third aspect of the present invention discloses a control unit, comprising a memory and a controller which are communicatively connected in sequence, wherein a computer program is stored in the memory, and wherein the controller is used to read the computer program and execute a hybrid tractor target torque control method according to the first aspect or a hybrid tractor adaptive control method according to the second aspect.

[0008] A fourth aspect of the present invention discloses a hybrid tractor adaptive control system, comprising: A data acquisition unit, the data acquisition unit includes a vehicle speed acquisition module, a throttle opening acquisition module, a brake opening acquisition module, a torque acquisition module, and a range extender discharge power acquisition module; A vehicle controller, the data acquisition unit is connected to the vehicle controller by signal; A control unit as described in the third aspect, wherein the control unit is connected to the vehicle controller by signal; A drive motor controller generates a control instruction according to the target torque and / or the power generation power beat power of the control unit.

[0009] The beneficial effects of the present invention are: 1. The present invention aims at the correlation between the working parameters of the components of the series hybrid tractor and the vehicle speed, takes the actual vehicle speed, throttle opening, brake pedal opening and the corresponding change rate as input conditions, constructs a correlation model with the discharge power demand of the range extender, the target torque of the drive motor and the vehicle speed, combines the actual torque of the drive motor, the calculated value of the target torque of the drive motor, the actual discharge power of the range extender, the target discharge power of the range extender, and the output parameters of the vehicle speed model as input, and performs adaptive control of the range extender and the drive motor, which can improve the driving experience in actual operation while improving the energy utilization efficiency.

[0010] 2. The method of the present invention is based on the working parameters of the components of the existing series hybrid tractor, does not require additional components, and does not increase costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only 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.

[0012] Figure 1 It is a principle block diagram of the hybrid tractor adaptive control system of the present invention. DETAILED DESCRIPTION

[0013] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0014] Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. 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.

[0015] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0016] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate the orientation or positional relationship that the product of the invention is usually placed in when in use, or the orientation or positional relationship that is commonly understood by those skilled in the art, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the control unit or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second" and the like are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0017] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0018] The first aspect of the present invention discloses a hybrid tractor target torque control method, including steps S01 to S06. It should be noted that the step identifiers in this solution are only for the convenience of explaining the method, and do not constitute a sequence limitation. The sequence of each step is based on its language description and the sequence of each signal.

[0019] Step S01, receiving vehicle speed information within a period of time.

[0020] Step S02: determining the vehicle speed change rate and the number of vehicle speed change counters according to the vehicle speed information.

[0021] Specifically, the vehicle speed change counter includes a first vehicle speed change counter and a second vehicle speed change counter. In this step, the vehicle speed change rate is first determined based on the vehicle speed information. When the vehicle speed change rate is less than a first threshold, the first vehicle speed change counter counts up by 1; when the vehicle speed change rate is greater than a second threshold, the second vehicle speed change counter counts up by 1, wherein the first threshold is less than the second threshold.

[0022] The settings of the above thresholds are calibrated after actual testing.

[0023] Step S03, in response to the vehicle speed change rate and the number of times of the vehicle speed change counter satisfying a preset condition, obtaining throttle opening information and vehicle status in the vehicle controller.

[0024] Specifically, the preset conditions include condition A and condition B. Condition A is that the vehicle speed change rate is less than the first threshold and the number of counts of the first vehicle speed change counter is greater than the third threshold; condition B is that the vehicle speed change rate is greater than the second threshold and the number of counts of the second vehicle speed change counter is greater than the fourth threshold; wherein the third threshold is less than the fourth threshold.

[0025] When the vehicle speed change rate is less than the first threshold and the number of counts of the first vehicle speed change counter is greater than the third threshold, adaptive control is triggered; when the vehicle speed change rate is greater than the second threshold and the number of counts of the second vehicle speed change counter is greater than the fourth threshold, adaptive control is also triggered; wherein the third threshold is less than the fourth threshold.

[0026] That is, if the above condition A or condition B is met, the adaptive control is triggered.

[0027] Step S04: determining the target torque to be optimized according to the vehicle state.

[0028] Step S05, determining a constant corresponding to the weakened or enhanced driving coefficient by looking up a table according to the preset conditions satisfied by the throttle opening information, the vehicle speed change rate and the number of times of the vehicle speed change counter, and determining the driving coefficient according to the constant corresponding to the driving coefficient.

[0029] This step adjusts the driving coefficient in different ways according to different throttle opening information and different preset conditions. The driving coefficient includes the vehicle speed model driving coefficient, the sliding energy recovery coefficient, and the braking energy recovery coefficient.

[0030] Specific: If the opening information indicates that the throttle opening is greater than zero, that is, the opening information indicates that the throttle opening is non-zero: The preset condition satisfied by the vehicle speed change rate and the number of times of the vehicle speed change counter is condition A, and the constant corresponding to the enhanced vehicle speed model driving coefficient is determined by looking up the table according to the vehicle speed change rate.

[0031] The preset condition satisfied by the vehicle speed change rate and the number of times of the vehicle speed change counter is condition B, and the constant corresponding to the weakened vehicle speed model driving coefficient is determined by looking up the table according to the vehicle speed change rate.

[0032] The vehicle speed model driving coefficient is then calculated based on the constant corresponding to the vehicle speed model driving coefficient, the target torque to be optimized, and the actual torque of the drive motor; specifically, the vehicle speed model driving coefficient Par_VSpdMod_Drv is calculated as follows: Par_VSpdMod_Drv= Cd*(T'-T) / T, Cd is the constant corresponding to the driving coefficient of the vehicle speed model, T' is the target torque to be optimized; T is the actual torque of the current driving motor.

[0033] If the opening information indicates that the throttle opening is zero, the brake opening information is obtained and the coasting energy recovery coefficient or the braking energy recovery coefficient is determined according to the brake information. Specifically: If the brake opening information indicates that the brake opening is zero and the vehicle speed change rate and the number of times of the vehicle speed change counter satisfy the preset condition A, a constant corresponding to the enhanced coasting energy recovery coefficient is determined by looking up a table according to the vehicle speed change rate; If the brake opening information indicates that the brake opening is zero and the vehicle speed change rate and the number of times of the vehicle speed change counter satisfy the preset condition A, a constant corresponding to the weakened coasting energy recovery coefficient is determined by looking up a table according to the vehicle speed change rate; The sliding energy recovery coefficient is calculated according to the constant corresponding to the sliding energy recovery coefficient, the target torque to be optimized, and the actual torque of the drive motor. Specifically, the sliding energy recovery coefficient Par_VspdMod_Sld_Rcy is calculated as follows: Par_VspdMod_Sld_Rcy=Cc*|(T'-T) / T| Cc is the constant corresponding to the coasting energy recovery coefficient, T' is the target torque to be optimized; and T is the actual torque of the current drive motor.

[0034] If the brake opening information indicates that the brake opening is greater than zero and the vehicle speed change rate and the number of times of the vehicle speed change counter meet the preset condition A, a constant corresponding to the enhanced brake energy recovery coefficient is determined by looking up a table according to the vehicle speed change rate; If the brake opening information indicates that the brake opening is greater than zero and the vehicle speed change rate and the number of times of the vehicle speed change counter meet the preset condition A, a constant corresponding to the weakened brake energy recovery coefficient is determined by looking up a table according to the vehicle speed change rate; The braking energy recovery coefficient is calculated based on the constant corresponding to the braking energy recovery coefficient, the target torque to be optimized, and the actual torque of the drive motor. Specifically, the braking energy recovery coefficient Par_VspdMod_Brk_Rcy is calculated as follows: Par_VspdMod_Brk_Rcy=Cb*|(T'-T) / T| Cb is the constant corresponding to the braking energy recovery coefficient, T' is the target torque to be optimized; T is the actual torque of the current driving motor.

[0035] Step S06: determining a target torque according to the target torque to be optimized and the driving coefficient.

[0036] Specifically, target torque = target torque to be optimized * driving coefficient.

[0037] Based on the hybrid tractor target torque control method disclosed in the first aspect, the second aspect of the present invention discloses a hybrid tractor adaptive control method. Specifically, the method includes the hybrid tractor target torque control method, and when acquiring the throttle opening information, further includes: Obtain the target discharge power and actual power of the range extender; Calculating the difference between the actual discharge power of the range extender and its corresponding target power; In response to the vehicle speed change rate and the number of times of the vehicle speed change counter satisfying the preset condition as condition A, the increased power generation power beat power is determined by looking up a table according to condition A and the difference; In response to the preset condition that the vehicle speed change rate and the number of times of the vehicle speed change counter meet the condition B, the weakened power generation power beat power is determined by looking up the table according to the condition B and the difference.

[0038] The third aspect of the present invention discloses a control unit, comprising a memory and a controller which are sequentially connected in communication, wherein a computer program is stored in the memory, and the controller is used to read the computer program and execute a hybrid tractor target torque control method in the first aspect or a hybrid tractor adaptive control method in the second aspect. Specifically, the memory may include, but is not limited to, a random access memory (RAM), a read-only memory (ROM), a flash memory (Flash Memory), a first-input first-output memory (FIFO) and / or a first-input last-output memory (FILO), etc.; the controller may not be limited to a microcontroller of the STM32F105 series. In addition, the computer device may also include, but is not limited to, a power supply unit, a display screen and other necessary components.

[0039] A fourth aspect of the present invention discloses a hybrid tractor adaptive control system, such as Figure 1 As shown, it includes a data acquisition unit, which includes but is not limited to a vehicle speed acquisition module, a throttle opening acquisition module, a brake opening acquisition module, a torque acquisition module, and a range extender discharge power acquisition module. It may also include a key switch signal acquisition module, a P / R / N / D gear position signal acquisition module, and other existing data acquisition modules on hybrid tractors. A vehicle controller, wherein the data acquisition unit is connected to the vehicle controller by signal; a control unit in the third aspect, wherein the control unit is connected to the vehicle controller by signal, wherein the control unit may be a separate unit, and in order to save costs, it may also be directly integrated into the vehicle controller, such as Figure 1 As shown, a drive motor controller generates a control instruction according to the target torque and / or the generated power beat power of the control unit.

[0040] Of course, other components of the hybrid tractor adaptive control system, such as Figure 1 The drive motor, engine controller, etc. are all existing technologies, and the circuit connection relationship between them is an existing relationship, which will not be repeated in this solution.

[0041] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present invention based on the technical revelations disclosed by the present invention, and these variations and combinations are still within the protection scope of the present invention.

Claims

1. A hybrid tractor target torque control method, characterized in that: The following steps are involved: Receive vehicle speed information within a period of time; determining a vehicle speed change rate and a number of vehicle speed change counters according to the vehicle speed information; In response to the vehicle speed change rate and the number of times of the vehicle speed change counter satisfying a preset condition, acquiring throttle opening information and vehicle status in the vehicle controller; Determining a target torque to be optimized according to the vehicle state; Determine a constant corresponding to the weakened or enhanced driving coefficient by looking up a table according to the preset conditions satisfied by the throttle opening information, the vehicle speed change rate and the number of times of the vehicle speed change counter, and determine the driving coefficient according to the constant corresponding to the driving coefficient; The target torque is determined according to the target torque to be optimized and the driving coefficient.

2. A hybrid tractor target torque control method according to claim 1, characterized in that: The vehicle speed change counter includes a first vehicle speed change counter and a second vehicle speed change counter. The determining the vehicle speed change rate and the number of times of the vehicle speed change counter according to the vehicle speed information comprises: determining a vehicle speed change rate according to the vehicle speed information; In response to the vehicle speed change rate being less than a first threshold, the first vehicle speed change counter counts up by 1; In response to the vehicle speed change rate being greater than a second threshold, the second vehicle speed change counter is incremented by 1, wherein the first threshold is less than the second threshold.

3. The hybrid tractor target torque control method according to claim 2, characterized in that: The preset conditions include condition A and condition B. Condition A is that the vehicle speed change rate is less than the first threshold and the number of counts of the first vehicle speed change counter is greater than the third threshold; Condition B is that the vehicle speed change rate is greater than the second threshold and the number of counts of the second vehicle speed change counter is greater than the fourth threshold; wherein the third threshold is less than the fourth threshold.

4. The hybrid tractor target torque control method according to claim 3, characterized in that: The method of determining a constant corresponding to the weakened or enhanced driving coefficient by looking up a table according to the preset conditions satisfied by the throttle opening information, the vehicle speed change rate, and the number of times of the vehicle speed change counter, and determining the driving coefficient according to the constant corresponding to the driving coefficient includes: In response to the opening information indicating that the throttle opening is greater than zero and the vehicle speed change rate and the number of times of the vehicle speed change counter satisfy the preset condition as condition A, a constant corresponding to the enhanced vehicle speed model driving coefficient is determined by looking up a table according to the vehicle speed change rate; In response to the opening information indicating that the throttle opening is greater than zero and the vehicle speed change rate and the number of times of the vehicle speed change counter satisfy the preset condition as condition B, a constant corresponding to the weakened vehicle speed model driving coefficient is determined by looking up a table according to the vehicle speed change rate; The vehicle speed model driving coefficient is calculated according to the constant corresponding to the vehicle speed model driving coefficient, the target torque to be optimized, and the actual torque of the driving motor.

5. The hybrid tractor target torque control method according to claim 3, characterized in that: The method of determining a constant corresponding to the weakened or enhanced driving coefficient by looking up a table according to the preset conditions satisfied by the throttle opening information, the vehicle speed change rate, and the number of times of the vehicle speed change counter, and determining the driving coefficient according to the constant corresponding to the driving coefficient includes: In response to the opening information indicating that the throttle opening is zero, obtaining brake opening information; In response to the brake opening information indicating that the brake opening is zero and the vehicle speed change rate and the number of times of the vehicle speed change counter satisfy the preset condition as condition A, a constant corresponding to the enhanced coasting energy recovery coefficient is determined by looking up a table according to the vehicle speed change rate; In response to the brake opening information indicating that the brake opening is zero and the vehicle speed change rate and the number of times of the vehicle speed change counter satisfy the preset condition as condition A, a constant corresponding to the weakened coasting energy recovery coefficient is determined by looking up a table according to the vehicle speed change rate; The coasting energy recovery coefficient is calculated according to the constant corresponding to the coasting energy recovery coefficient, the target torque to be optimized, and the actual torque of the driving motor.

6. The hybrid tractor target torque control method according to claim 3, characterized in that: The method of determining a constant corresponding to the weakened or enhanced driving coefficient by looking up a table according to the preset conditions satisfied by the throttle opening information, the vehicle speed change rate, and the number of times of the vehicle speed change counter, and determining the driving coefficient according to the constant corresponding to the driving coefficient includes: In response to the opening information indicating that the throttle opening is zero, obtaining brake opening information; In response to the brake opening information indicating that the brake opening is greater than zero and the vehicle speed change rate and the number of times of the vehicle speed change counter satisfy the preset condition as condition A, a constant corresponding to the enhanced brake energy recovery coefficient is determined by looking up a table according to the vehicle speed change rate; In response to the brake opening information indicating that the brake opening is greater than zero and the vehicle speed change rate and the number of times of the vehicle speed change counter satisfy the preset condition as condition A, a constant corresponding to the weakened brake energy recovery coefficient is determined by looking up a table according to the vehicle speed change rate; The braking energy recovery coefficient is calculated according to the constant corresponding to the braking energy recovery coefficient, the target torque to be optimized, and the actual torque of the driving motor.

7. The hybrid tractor target torque control method according to claim 3, characterized in that: The target torque is determined according to the target torque to be optimized and the driving coefficient as follows: Target torque = target torque to be optimized * driving coefficient.

8. A hybrid tractor adaptive control method, characterized in that: A hybrid tractor target torque control method comprising any one of claims 1 to 7, The acquisition of throttle opening information also includes: Obtain the target discharge power and actual power of the range extender; Calculating the difference between the actual discharge power of the range extender and its corresponding target power; In response to the vehicle speed change rate and the number of times of the vehicle speed change counter satisfying the preset condition as condition A, the increased power generation power beat power is determined by looking up a table according to condition A and the difference; In response to the preset condition that the vehicle speed change rate and the number of times of the vehicle speed change counter meet the condition B, the weakened power generation power beat power is determined by looking up the table according to the condition B and the difference.

9. A control unit, comprising a memory and a controller which are communicatively connected in sequence, wherein a computer program is stored in the memory, characterized in that: The controller is used to read the computer program and execute the hybrid tractor target torque control method described in any one of claims 1 to 7 or the hybrid tractor adaptive control method described in claim 8.

10. A hybrid tractor adaptive control system, characterized in that: include: A data acquisition unit, the data acquisition unit includes a vehicle speed acquisition module, a throttle opening acquisition module, a brake opening acquisition module, a torque acquisition module, and a range extender discharge power acquisition module; A vehicle controller, the data acquisition unit is connected to the vehicle controller by signal; A control unit as claimed in claim 9, wherein the control unit is connected to the vehicle controller by signal; A drive motor controller generates a control instruction according to the target torque and / or the power generation power beat power of the control unit.

Images