Differential backlash compensation method, electronic device and vehicle

Abstract

The present application relates to the technical field of vehicles, and provides a differential gear backlash compensation method, electronic equipment and a vehicle; the differential gear backlash compensation method comprises the following steps: S1: calculating the current differential gear internal backlash according to the working condition decoupling characteristics of the planet gear only revolving without rotating in the vehicle straight running condition and the planet gear revolving and rotating in the steering condition; S2: obtaining the differential gear wear amount according to the difference between the current differential gear internal backlash and the pre-labeled differential gear initial internal backlash; S3: determining the differential gear wear level based on the obtained differential gear wear amount; S4: configuring the torque change slope of the gear passing through multiple stages of the current differential gear internal backlash according to the wear level of the differential gear and the running condition, and performing torque transition control. The present application solves the technical pain points that the prior art is difficult to accurately identify the internal wear of the differential gear and the poor backlash compensation effect.

Description

Technical Field

[0001] This invention relates to the field of vehicle technology, and in particular to a differential backlash compensation method, electronic equipment, and vehicle. Background Technology

[0002] Current backlash compensation and wear identification technologies for electric drive systems suffer from four common problems: 1. Fixed compensation values ​​cannot adapt to wear throughout the entire life cycle. Existing backlash compensation methods are mostly fixed parameters calibrated at the production line. As the differential bevel gears wear down with mileage, the backlash gradually increases. Fixed compensation values ​​lead to the problem of "over-compensation for new cars and under-compensation for older cars": new cars are prone to reverse impacts, while older cars experience increased backlash impact noise and torque response lag, failing to meet the NVH and power performance requirements throughout the entire life cycle.

[0003] 2. Inability to distinguish the backlash contribution of the differential and the final drive gears. Conventional transmission backlash testing can only measure the total backlash of the "final drive + differential," and cannot separately locate the wear of the bevel gears inside the differential. Furthermore, the wear rates and failure modes of the bevel gears inside the differential are completely different from those of the final drive gears. Therefore, total backlash compensation cannot specifically optimize the meshing impact of the differential, resulting in poor compensation accuracy.

[0004] 3. Reliance on additional sensors leads to high mass production costs. Some high-precision wear identification solutions require the addition of torque and displacement sensors, significantly increasing hardware costs and assembly difficulty, making them unsuitable for widespread use in mass-produced electric drives; solutions relying solely on motor current estimation suffer from large torque estimation errors and insufficient identification accuracy.

[0005] 4. Poor robustness due to failure to consider operating conditions and environmental interference. Most solutions do not distinguish between straight-line, steering, slippage, and temperature conditions, misjudging backlash changes caused by thermal expansion and contraction and speed differences caused by slippage as wear. The identification results fluctuate greatly, and the compensation logic is prone to false triggering, which may exacerbate the impact on the transmission system. Summary of the Invention

[0006] The purpose of this invention is to provide a differential backlash compensation method, electronic device, and vehicle; this invention solves the technical pain points of existing technologies, such as the difficulty in accurately identifying internal wear of the differential and poor backlash compensation effect. The specific solution is as follows: A method for compensating backlash in a differential includes the following steps: S1: Calculate the current internal backlash of the differential based on the decoupling characteristics of the planetary gears revolving without rotating on their own axis under the straight-moving condition and revolving and rotating under the steering condition. S2: Obtain the differential wear amount based on the difference between the current internal backlash of the differential and the pre-calibrated initial internal backlash of the differential; S3: Determine the differential wear level based on the acquired differential wear amount; S4: Based on the wear level of the differential and the driving conditions, configure the torque change slope of the gear through multiple stages of the current differential backlash and perform torque transition control.

[0007] Optionally, the process may include the following steps prior to step S1: S0: Trigger differential backlash detection when preset conditions are met; if any preset condition is not met, maintain the slope of torque change corresponding to the previous differential wear amount and multiple stages of gear passing through the front differential backlash. The preset conditions include the following: Torque commutation zero-crossing condition judgment: When the real-time output torque of the motor falls into the positive and negative torque switching threshold range and the torque change rate is within the preset range, the motor is judged to have entered the torque commutation zero-crossing condition. Driving steady-state condition judgment: If the vehicle speed fluctuation range is less than the preset fluctuation value, the vehicle is judged to have entered the driving steady-state condition. Vehicle straight-ahead and turning condition judgment: When the steering wheel angle is less than the first preset angle, the vehicle is determined to be in a straight-ahead condition; when the steering wheel angle enters the range between the second and third preset angles, and the steering wheel angle fluctuation rate is less than the angle threshold, the vehicle is determined to be in a turning condition. Oil temperature operating range judgment: When the reducer oil temperature is within the preset oil temperature operating range, it is judged that the reducer oil temperature is within the oil temperature operating range.

[0008] Optionally, step S1 includes: S101: Obtain the initial backlash of the differential based on the pre-calibrated initial total backlash S0 under straight-line working conditions and the initial total backlash S1 under steady-state steering conditions; the initial backlash of the differential is used to characterize the standard value of the initial internal backlash of the differential. In the straight-line condition, the initial total backlash S0 is equal to the main backlash reduction; in the steady-state steering condition, the initial total backlash S1 is equal to the initial value of the main backlash reduction S0 plus the initial backlash of the differential ΔS0. S102: When the vehicle is running, if the preset conditions are met at the same time, the backlash detection inside the differential is triggered, and the real-time straight backlash S0' and real-time steering backlash S1' are calculated. S103: Based on the difference between the real-time steering total backlash S1' and the real-time straight total backlash S0', the real-time differential internal backlash ΔS'=S1'-S0' is obtained; Correspondingly: Step S2 includes: obtaining the differential wear amount based on the difference between the real-time internal backlash of the differential and the initial backlash of the differential; Step S3 includes: determining the differential wear level based on the differential wear amount compared to the preset wear range.

[0009] Optionally, step S103 may be followed by: an interference compensation strategy step; The corrected internal backlash of the differential is calculated using an interference compensation strategy. The wear of the differential is obtained by comparing the difference between the corrected internal backlash and the initial backlash of the differential. The calculation formula for the interference compensation strategy is: Corrected differential internal tooth backlash = Real-time differential internal tooth backlash - α × (T - T0) × D; α is the coefficient of thermal expansion, T is the current oil temperature of the reducer, T0 is the reference oil temperature, and D is the pitch circle diameter of the gear.

[0010] Optionally, the multiple stages of step S4 include at least: a rapid approach stage, a buffer fitting stage, and a steady-state loading stage; the driving conditions include at least: a first driving condition, a rapid speed change condition, and a high-speed cruise condition; Step S4 includes: Based on the wear level of the differential, the torque change slope of the gear passing through the internal tooth backlash of the front differential is configured for the rapid approach section and the buffer engagement section; wherein, the rapid approach section is configured such that the higher the wear level, the wider the internal tooth backlash of the front differential, and the greater the torque change slope of the rapid approach section; the buffer engagement section is configured with a lower torque change slope than the rapid approach section. Based on the first driving condition, rapid speed change condition, and high-speed condition, the torque change slope compensation strength of the gears is pre-configured for the rapid approach segment through the backlash inside the front differential.

[0011] Optionally, step S4 further includes: When the gear tooth surface disengages and the torque begins to cross zero in the reverse direction, the torque change slope of the gear passing through the backlash inside the front differential and the low-position torque change slope of the buffer contact section are obtained according to the wear level. When the driving condition is the first driving condition, the compensation intensity of the torque change slope during the rapid approach phase is reduced by a first preset ratio; wherein, the first driving condition includes at least: low-speed crawling and parking conditions. When the driving condition is a rapid speed change condition, the compensation intensity of the torque change slope in the rapid approach phase is increased by a second preset ratio; wherein, the rapid speed change condition includes at least: rapid acceleration, rapid deceleration, and getting out of trouble. When the driving condition is high-speed cruise, the torque change slope of the rapid approach segment is reduced to the preset base torque change slope.

[0012] Optionally, it also includes S5: graded early warning steps; The tiered early warning process includes: Based on the wear level of the differential, corresponding warning prompts and torque limit ratios are generated; Based on the wear level of the differential, corresponding warning prompts and torque limiting ratios are generated, including: When the wear level is low wear, warning prompts and peak torque limit ratios should not be generated.

[0013] Optionally, it also includes S6: differential life warning procedure; The differential life warning procedure includes: Based on the wear level, retrieve historical wear data; wherein, the historical wear data includes at least: cumulative operating mileage, torque load, and wear amount; Retrieve current and historical wear data to construct and train a differential wear rate model; wherein, the input parameters of the wear rate model include cumulative operating mileage, torque load, and wear amount, and the output is the remaining service life of the differential; When the calculated remaining service life is less than the preset service life threshold, a differential wear life warning is issued.

[0014] An electronic device includes: a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other via the communication bus; the memory stores a computer program, which, when executed by the processor, causes the processor to perform the steps of the method.

[0015] A computer-readable storage medium storing a computer program executable by an electronic device, which, when run on the electronic device, causes the electronic device to perform the steps of the method.

[0016] A vehicle comprising: An electronic device for implementing the steps of the method; A processor that runs a program, and when the program runs, it executes the steps of the method from data output by the electronic device. A storage medium for storing a program that, when run, executes the steps of the method on data output from an electronic device.

[0017] The beneficial effects of this invention are as follows: This invention provides a differential backlash compensation method, electronic equipment, and vehicle. By utilizing the differentiated motion decoupling characteristics of the planetary gears in the differential under straight-line and steering conditions, it isolates the detection interference caused by the meshing backlash of the main reducer and can separately calculate the internal backlash of the differential bevel gear. This overcomes the shortcomings of traditional detection methods, which can only obtain the total backlash of the main reducer and differential assembly, and cannot separately separate the wear degree of the differential gears. Then, based on the measured backlash difference, the wear amount is obtained and the wear level is determined. Combined with real-time driving conditions, the entire process of the current differential internal backlash is divided into multiple stages, and the torque change slope corresponding to multiple stages is configured to achieve adaptive torque transition control. The advantage of this design is that this invention can dynamically adjust the backlash compensation parameters according to the wear state of the gear throughout its entire life cycle, and avoids technical problems such as fixed compensation parameters being difficult to adapt to gear wear, gear impact noise caused by operating condition disturbances, and power lag, according to the usage requirements of different driving conditions. It solves the technical problems of existing technologies that are difficult to accurately identify the internal wear of the differential and have poor backlash compensation effects. Attached Figure Description

[0018] Figure 1 This is a schematic flowchart of a differential backlash compensation method according to an embodiment of the present invention. Figure 2 This is a schematic flowchart of a differential backlash compensation method according to one embodiment of the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the following description will be provided in conjunction with the appendix. Figures 1 to 2 The present invention will be described in further detail below. It is obvious that the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0020] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms, and “multiple” generally includes at least two unless the context clearly indicates otherwise.

[0021] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0022] It should be understood that although the terms first, second, third, etc., may be used in the embodiments of the present invention, these descriptions should not be limited to these terms. These terms are only used to distinguish the descriptions. For example, first may also be referred to as second without departing from the scope of the embodiments of the present invention, and similarly, second may also be referred to as first.

[0023] Depending on the context, the words “if” or “suppose” as used here can be interpreted as “when” or “in response to determination” or “in response to detection.” Similarly, depending on the context, the phrases “if determination” or “if detection (of the stated condition or event)” can be interpreted as “when determination” or “in response to determination” or “when detection (of the stated condition or event)” or “in response to detection (of the stated condition or event).”

[0024] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device that includes said element.

[0025] It should be noted that any symbols and / or numbers present in the specification that are not marked in the accompanying drawings are not reference numerals.

[0026] See Figure 1 and Figure 2 The differential backlash compensation method shown includes the following steps: S1: Calculate the current internal backlash of the differential based on the decoupling characteristics of the planetary gears revolving without rotating on their own axis under the straight-moving condition and revolving and rotating under the steering condition. S2: Obtain the differential wear amount based on the difference between the current internal backlash of the differential and the pre-calibrated initial internal backlash of the differential; S3: Determine the differential wear level based on the acquired differential wear amount; S4: Based on the wear level of the differential and the driving conditions, configure the torque change slope of the gear through multiple stages of the current differential backlash and perform torque transition control.

[0027] Specifically, this invention innovatively utilizes the differentiated motion decoupling characteristics of the planetary gears in the differential under straight-line and steering conditions to isolate detection interference caused by the meshing backlash of the main reducer. It can also independently calculate the internal backlash of the differential bevel gears, overcoming the shortcomings of traditional detection methods that can only obtain the total backlash of the main reducer and differential assembly, and cannot separately isolate the wear degree of the differential gears. Then, based on the measured backlash difference, the wear amount is obtained and the wear level is determined. Furthermore, combined with real-time driving conditions, the entire process of navigating the internal backlash of the differential is divided into multiple stages, and the torque change slope corresponding to each stage is configured to achieve adaptive torque transition control. The advantage of this design is that it can dynamically adjust backlash compensation parameters (such as torque change slope) according to the wear state throughout the gear's entire life cycle. Based on the usage requirements of different driving conditions, while meeting the requirements of power response speed and transmission meshing smoothness, it avoids technical problems such as fixed compensation parameters being difficult to adapt to gear wear, gear impact noise caused by operating condition disturbances, and power lag. This solves the technical pain points of existing technologies, such as difficulty in accurately identifying internal wear of the differential and poor backlash compensation effects.

[0028] It should be noted that this embodiment uses the standard sensor of the electric drive system as the input signal, and no additional hardware is required. Input signal sources: motor resolver rotor angle signal, left and right wheel speed signals, motor torque command / current signal, reducer oil temperature signal, steering wheel angle signal, ESP / ABS status signal.

[0029] It is understood that this invention is based on the inherent mechanical characteristics of the differential, takes zero additional hardware as the premise for implementation, and takes dynamic adaptation throughout the entire life cycle as the compensation goal. Through a four-layer closed loop of "operating condition screening, wear separation identification, adaptive compensation, and life management", it avoids four common problems of existing technologies: "poor adaptability of fixed compensation value throughout the entire life cycle, inability to distinguish independent wear of differential, reliance on additional hardware for high-precision identification, and poor robustness of traditional strategies".

[0030] In one specific embodiment, the method further includes the following step before step S1: S0: Trigger differential backlash detection when preset conditions are met; if any preset condition is not met, maintain the slope of torque change corresponding to the previous differential wear amount and multiple stages of gear passing through the front differential backlash. The preset conditions include the following: Torque commutation zero-crossing condition judgment: When the real-time output torque of the motor falls into the positive and negative torque switching threshold range and the torque change rate is within the preset range, the motor is judged to have entered the torque commutation zero-crossing condition. Driving steady-state condition judgment: If the vehicle speed fluctuation range is less than the preset fluctuation value, the vehicle is judged to have entered the driving steady-state condition. Vehicle straight-ahead and turning condition judgment: When the steering wheel angle is less than the first preset angle, the vehicle is determined to be in a straight-ahead condition; when the steering wheel angle enters the range between the second and third preset angles, and the steering wheel angle fluctuation rate is less than the angle threshold, the vehicle is determined to be in a turning condition. Oil temperature operating range judgment: When the reducer oil temperature is within the preset oil temperature operating range, it is judged that the reducer oil temperature is within the oil temperature operating range.

[0031] It can be understood that the preset conditions need to be met simultaneously: (1) Torque zero crossing judgment: The motor torque is in the positive and negative switching range and the torque change rate is in the set stable range, excluding the dynamic loading condition of large torque; (2) Driving stability judgment: vehicle speed fluctuation rate < 5km / h, no sudden acceleration or deceleration, no wheel slippage, and no ESP / ABS intervention triggered; (3) Steering state determination: Distinguish between two steady-state scenarios: "straight driving (steering wheel angle < 3°)" and "steady-state steering (steering wheel angle is stable between 5° and 30°, and the angle fluctuation rate is < 1° / s)"; (4) Oil temperature range determination: The reducer oil temperature is within the normal operating range of 20℃ to 90℃, excluding cold start and extreme high temperature conditions.

[0032] When the conditions are met, the backlash detection inside the differential is triggered; if the conditions are not met, the previous wear amount and compensation parameters remain unchanged. The compensation parameters include the torque change slope corresponding to multiple stages of the gear passing through the backlash inside the front differential.

[0033] It should be noted that backlash is essentially the meshing clearance of a gear pair when it is unloaded. It can only be accurately measured by angle difference during the "no-load stroke" when the torque is reversed and the tooth surface separates from one side and fits against the other side. When the gear is under load, the tooth surface is always pressed together, and the true backlash cannot be measured.

[0034] Meanwhile, fluctuations in vehicle speed, wheel slippage, sudden changes in steering angle, and thermal expansion and contraction can all cause significant deviations in the angle detection value. If the detection is performed directly without screening, the interference of the working condition will be misjudged as backlash wear, leading to the false triggering of the compensation logic.

[0035] The beneficial effects of configuring preset conditions are as follows: Ensuring recognition accuracy from the source: Eliminating more than 90% of interfering operating conditions, avoiding misjudging road condition fluctuations and operational changes as differential wear, and controlling the steady-state error of wear recognition to within 0.02mm; To avoid secondary problems caused by miscompensation: prevent compensation parameters from frequently changing with the detection value, which could lead to unexpected torque fluctuations and jerking in the transmission system, and ensure smooth driving. Zero hardware cost implementation: Using existing sensors in the vehicle, there is no need to install torque sensors, vibration sensors, or displacement sensors, resulting in no additional costs or assembly processes.

[0036] In one specific embodiment, step S1 includes: S101: Obtain the initial backlash of the differential based on the pre-calibrated initial total backlash S0 under straight-line working conditions and the initial total backlash S1 under steady-state steering conditions; the initial backlash of the differential is used to characterize the standard value of the initial internal backlash of the differential. In the straight-line condition, the initial total backlash S0 is equal to the main backlash reduction; in the steady-state steering condition, the initial total backlash S1 is equal to the initial value of the main backlash reduction S0 plus the initial backlash of the differential ΔS0. S102: When the vehicle is running, if the preset conditions are met at the same time, the backlash detection inside the differential is triggered, and the real-time straight backlash S0' and real-time steering backlash S1' are calculated. S103: Based on the difference between the real-time steering total backlash S1' and the real-time straight total backlash S0', the real-time differential internal backlash ΔS'=S1'-S0' is obtained; Correspondingly: Step S2 includes: obtaining the differential wear amount based on the difference between the real-time internal backlash of the differential and the initial backlash of the differential; Step S3 includes: determining the differential wear level based on the differential wear amount compared to the preset wear range.

[0037] In one specific embodiment, step S103 is followed by an interference compensation strategy step. The corrected internal backlash of the differential is calculated using an interference compensation strategy. The wear of the differential is obtained by comparing the difference between the corrected internal backlash and the initial backlash of the differential. The calculation formula for the interference compensation strategy is: Corrected differential internal tooth backlash = Real-time differential internal tooth backlash - α × (T - T0) × D; α is the coefficient of thermal expansion, T is the current oil temperature of the reducer, T0 is the reference oil temperature, and D is the pitch circle diameter of the gear.

[0038] It is understood that this invention uses the real-time reducer oil temperature and the thermal expansion coefficient of the gear material to perform thermal correction on the differential internal tooth backlash detection value in order to complete temperature compensation and ensure the accuracy of the calculated differential internal tooth backlash.

[0039] In this embodiment, the wear of the main reducer is separated: the wear amount of the total backlash in the straight line (S0'-S0) is recorded separately as the wear amount of the main reducer and is not included in the differential wear calculation, so as to avoid the main reducer deterioration interfering with the differential compensation; In a further embodiment of this invention, an outlier filtering method is used to determine the wear amount of the differential. Specifically, a moving average filter is used, and if the wear amount of the differential in a single detection deviates from the historical average by more than 20%, it is determined to be an invalid value. The average value of the wear amount of the differential in five consecutive valid detections is taken as the final wear amount.

[0040] It should be noted that existing technology can only measure the total backlash of the main reducer and differential, and cannot distinguish the wear contribution of the two. The wear patterns of the differential and the main reducer are completely different: the main reducer gears are constantly meshed and have a stable wear rate, while the differential only experiences relative wear when turning, has a lower wear rate but deteriorates faster due to impact. Traditional total backlash compensation cannot specifically solve the backlash impact problem of the differential, and the compensation accuracy is insufficient.

[0041] This solution utilizes the inherent motion characteristics of the differential (i.e., the decoupling characteristics of planetary gears revolving only without rotating on their own axis during straight-line driving and revolving and rotating during steering), directly separating the independent backlash of the differential through the difference between these two types of conditions. This is equivalent to achieving independent online detection of the differential gear pair without disassembling the drivetrain, offering the following advantages: For the first time, online identification of independent wear of differentials has been achieved: This breaks through the limitation of existing technology that can only detect the backlash of the main drive, and can locate the backlash deterioration of the differential separately, providing targeted compensation and improvement of more than 40%, thus solving the problem of backlash impact specific to differentials from the root. Continuous tracking throughout the entire driving cycle: No need to stop, no need for test benches, no need for disassembly; the wear amount can be periodically updated during normal vehicle operation, realizing real-time status perception of the differential throughout its entire life cycle. Eliminate interference from the environment and related components: The triple mechanism of temperature compensation, main reducer wear separation and outlier filtering ensures that the wear identification results are not affected by temperature, main reducer deterioration and road conditions. It is robust and suitable for use in all regions and all scenarios. Provides data support for after-sales maintenance: It can quantify the actual wear status of the differential, replace the traditional "mileage-based maintenance" model, realize maintenance based on actual conditions, and reduce user operating costs.

[0042] In one specific embodiment, the multiple stages of step S4 include at least: a rapid approach stage, a buffer fitting stage, and a steady-state loading stage; the driving conditions include at least: a first driving condition, a rapid speed change condition, and a high-speed cruise condition; Step S4 includes: Based on the wear level of the differential, the torque change slope of the gear passing through the internal tooth backlash of the front differential is configured for the rapid approach section and the buffer engagement section; wherein, the rapid approach section is configured such that the higher the wear level, the wider the internal tooth backlash of the front differential, and the greater the torque change slope of the rapid approach section; the buffer engagement section is configured with a lower torque change slope than the rapid approach section. Based on the first driving condition, rapid speed change condition, and high-speed condition, the torque change slope compensation strength of the gears is pre-configured for the rapid approach segment through the backlash inside the front differential.

[0043] Specifically, in this embodiment, the backlash crossing process is divided into three control stages: a rapid approach stage, a buffer engagement stage, and a steady-state loading stage. Torque change slopes are configured for the rapid approach stage and the buffer engagement stage, respectively. The buffer engagement stage is configured with a lower torque change slope than the rapid approach stage to reduce the rate of torque change and suppress gear impact noise when the gear teeth approach and mesh. The rapid approach stage adaptively configures the torque change slope according to the differential wear level; the higher the wear level and the wider the backlash, the greater the torque change slope in the rapid approach stage, thereby compensating for the large backlash. Power lag; further, for the first driving condition, rapid speed change condition and high-speed cruise condition, the corresponding torque change slope compensation intensity is set only for the rapid approach section; the low torque change slope configured for the buffer engagement section no longer scales and adjusts with the operating condition, so that the main backlash travel can be dynamically adapted with wear and operating conditions, and the constant vibration damping parameters are maintained during the meshing buffer stage, ensuring power response, low-speed smoothness and high-speed torque stability in multiple scenarios, overcoming the technical defects of traditional fixed parameter backlash compensation that is difficult to adapt to gear wear and insufficient operating condition adaptability.

[0044] In one specific embodiment, step S4 further includes: When the gear tooth surface disengages and the torque begins to cross zero in the reverse direction, the torque change slope of the gear passing through the backlash inside the front differential and the low-position torque change slope of the buffer contact section are obtained according to the wear level. When the driving condition is the first driving condition, the compensation intensity of the torque change slope during the rapid approach phase is reduced by a first preset ratio; wherein, the first driving condition includes at least: low-speed crawling and parking conditions. When the driving condition is a rapid speed change condition, the compensation intensity of the torque change slope in the rapid approach phase is increased by a second preset ratio; wherein, the rapid speed change condition includes at least: rapid acceleration, rapid deceleration, and getting out of trouble. When the driving condition is high-speed cruise, the torque change slope of the rapid approach segment is reduced to the preset base torque change slope.

[0045] It is understood that in this embodiment, the process of torque crossing zero and passing through the backlash is divided into three stages, and the parameters of each stage are dynamically adjusted according to the amount of wear: (1) Torque control mode: Adaptive backlash interval slope + smooth end transition 1. Rapid approach phase (occupying 85%-90% of the stroke): After the tooth surface separates, it quickly traverses the main tooth backlash area with a high torque change rate; the greater the wear and the wider the tooth backlash, the higher the torque change slope in this phase (20% increase for moderate wear, 40% increase for heavy wear). 2. Buffer contact section: Just before the tooth surfaces are about to contact (determined by compensation angle calculation), the torque change rate is automatically reduced, and a buffer stroke of 10% to 15% is set to complete the tooth surface contact at a low speed. ③ Steady-state loading segment: After the tooth surfaces are fully engaged, the normal torque loading slope is restored.

[0046] (2) Compensation intensity for working conditions Low-speed crawling and parking conditions: compensation intensity is reduced by 30% to prioritize smoothness and avoid slight compensation fluctuations that may cause jerking sensations. Rapid acceleration, rapid deceleration, and getting out of trouble: The compensation strength is increased by 20%, prioritizing the power response speed and eliminating power lag caused by backlash; High-speed cruise mode: weaken the compensation logic and retain only the basic compensation to avoid over-compensation leading to steady-state torque fluctuations.

[0047] Example Torque change slope in the rapid approach phase with low wear: 20 Nm / ms (new backlash, no wear reference) Wear gain: 20% increase in the rapid wear phase for moderate wear, 40% increase in the rapid wear phase for heavy wear. The slope of the low-position torque change in the fixed buffer bonding section is 5 Nm / ms.

[0048] The total backlash angle is 9° (severe wear), the buffer stroke is 12%, and the buffer angle is 1.08°; the rapid approach section needs to travel 7.92°. The torque change slope of the rapid approach section under severe wear is 20 × 1.4 = 28 Nm / ms; and it passes through a 7.92° backlash stroke with this slope; 2. Buffer bonding section: 5 Nm / ms for passing through the remaining 1.08°; 3. After the tooth surfaces are fully engaged, turn off backlash compensation and activate the vehicle's native torque change slope under constant speed conditions.

[0049] It should be noted that both types of core problems caused by tooth backlash worsen as wear increases: Lag in power response: When the torque is reversed, the motor needs to rotate through the backlash before the wheel can receive torque; the wider the backlash, the longer the lag time and the slower the power response. Tooth surface impact noise: The tooth surface impacts after passing through the empty stroke. The wider the tooth gap, the faster the impact speed, the greater the impact energy, and the more obvious the abnormal noise and wear.

[0050] The existing fixed compensation scheme has inherent contradictions: If the compensation amount is set according to the small tooth backlash of a new car, the tooth backlash will increase after the vehicle wears out, and the compensation amount will be insufficient, so the lag and impact cannot be effectively suppressed. If the compensation amount is set according to the large backlash of the old car, the compensation will be excessive in the new car stage, the tooth surface will be continuously pressed, the drag loss will be increased, and the early wear will be accelerated.

[0051] The dynamic adaptive logic of this patent matches the optimal compensation parameters for different wear stages: when the tooth gap is wide, the crossing speed is increased to solve the lag, while the buffer section is increased to reduce the impact energy; when the tooth gap is narrow, the compensation amplitude is reduced to avoid overcompensation, thus achieving the optimal balance throughout the entire life cycle.

[0052] Beneficial effects Solving the problem of full life cycle adaptation: Completely eliminate the pain point of "over-compensation for new cars and under-compensation for old cars". Throughout the entire life cycle of the differential, the peak value of backlash impact can be stably reduced by more than 50%, and the power response lag time can be shortened by more than 30%. Balancing responsiveness and smoothness: The graded slope + buffer section design ensures both the dynamic response speed under wide backlash and avoids aggravated impact, breaking the contradiction of the traditional solution that "fast response inevitably leads to large impact". Slowing down the rate of wear and deterioration: Precise buffer fit control reduces the impact energy on the tooth surface, which can reduce impact fatigue damage to differential gears and extend the service life of the differential by 15% to 20%; Full-scenario adaptation: The working condition-differentiated compensation logic can simultaneously meet the smoothness requirements of urban commuting and the responsiveness requirements of off-road extrication, without requiring the driver to manually switch modes.

[0053] In one specific embodiment, it also includes S5: a graded early warning step; The tiered early warning process includes: Based on the wear level of the differential, corresponding warning prompts and torque limit ratios are generated; Based on the wear level of the differential, corresponding warning prompts and torque limiting ratios are generated, including: When the wear level is low wear, warning prompts and peak torque limit ratios should not be generated.

[0054] For example: Slight wear: Normal operation, compensation parameters are adaptively adjusted, no prompts; Moderate wear: The controller stores fault codes, and the vehicle's infotainment system prompts "Differential should be checked and maintained." At the same time, peak torque under extreme conditions should be appropriately limited. Severe wear: Triggers a clear warning and limits the motor's peak torque to 70% to avoid serious failures such as tooth surface chipping and tooth breakage under high torque.

[0055] In one specific embodiment, the present invention further includes S6: a differential life warning step; The differential life warning procedure includes: Based on the wear level, retrieve historical wear data; wherein, the historical wear data includes at least: cumulative operating mileage, torque load, and wear amount; Retrieve current and historical wear data to construct and train a differential wear rate model; wherein, the input parameters of the wear rate model include cumulative operating mileage, torque load, and wear amount, and the output is the remaining service life of the differential; When the calculated remaining service life is less than the preset service life threshold, a differential wear life warning is issued.

[0056] For example: Wear trend prediction: Based on cumulative mileage, torque load, and wear data, establish a wear rate model to predict the remaining service life; One-click recalibration after service: After differential repair or replacement, recalibration can be triggered by a diagnostic tool to reset the wear reference without updating the controller firmware.

[0057] It is understood that the design advantages of this embodiment are as follows: By predicting wear trends, a wear rate model is established based on cumulative mileage, torque load, and wear data to predict remaining service life. One-click recalibration after service: After differential repair or replacement, recalibration can be triggered by a diagnostic tool to reset the wear reference without updating the controller firmware.

[0058] On the other hand, the present invention provides an electronic device, comprising: a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; characterized in that the memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the method described therein.

[0059] On the other hand, the present invention provides a computer-readable storage medium storing a computer program executable by an electronic device, which, when run on the electronic device, causes the electronic device to perform the steps of the method.

[0060] On the other hand, the present invention provides a vehicle comprising: An electronic device for implementing the steps of the method; A processor that runs a program, and when the program runs, it executes the steps of the method from data output by the electronic device. A storage medium for storing a program that, when run, executes the steps of the method on data output from an electronic device.

[0061] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A method for compensating backlash in a differential, characterized in that, Includes the following steps: S1: Calculate the current internal backlash of the differential based on the decoupling characteristics of the planetary gears revolving without rotating on their own axis under the straight-moving condition and revolving and rotating under the steering condition. S2: Obtain the differential wear amount based on the difference between the current internal backlash of the differential and the pre-calibrated initial internal backlash of the differential; S3: Determine the differential wear level based on the acquired differential wear amount; S4: Based on the wear level of the differential and the driving conditions, configure the torque change slope of the gear through multiple stages of the current differential backlash and perform torque transition control.

2. The differential backlash compensation method according to claim 1, characterized in that, Step S1 is preceded by: S0: Trigger differential backlash detection when preset conditions are met; if any preset condition is not met, maintain the slope of torque change corresponding to the previous differential wear amount and multiple stages of gear passing through the front differential backlash. The preset conditions include the following: Torque commutation zero-crossing condition judgment: When the real-time output torque of the motor falls into the positive and negative torque switching threshold range and the torque change rate is within the preset range, the motor is judged to have entered the torque commutation zero-crossing condition. Driving steady-state condition judgment: If the vehicle speed fluctuation range is less than the preset fluctuation value, the vehicle is judged to have entered the driving steady-state condition. Vehicle straight-ahead and turning condition judgment: When the steering wheel angle is less than the first preset angle, the vehicle is determined to be in a straight-ahead condition; when the steering wheel angle enters the range between the second and third preset angles, and the steering wheel angle fluctuation rate is less than the angle threshold, the vehicle is determined to be in a turning condition. Oil temperature operating range judgment: When the reducer oil temperature is within the preset oil temperature operating range, it is judged that the reducer oil temperature is within the oil temperature operating range.

3. The differential backlash compensation method according to claim 1, characterized in that, Step S1 includes: S101: Obtain the initial backlash of the differential based on the pre-calibrated initial total backlash S0 under straight-line working conditions and the initial total backlash S1 under steady-state steering conditions; the initial backlash of the differential is used to characterize the standard value of the initial internal backlash of the differential. In the straight-line condition, the initial total backlash S0 is equal to the main backlash reduction; in the steady-state steering condition, the initial total backlash S1 is equal to the initial value of the main backlash reduction S0 plus the initial backlash of the differential ΔS0. S102: When the vehicle is running, if the preset conditions are met at the same time, the backlash detection inside the differential is triggered, and the real-time straight backlash S0' and real-time steering backlash S1' are calculated. S103: Based on the difference between the real-time steering total backlash S1' and the real-time straight total backlash S0', the real-time differential internal backlash ΔS'=S1'-S0' is obtained; Correspondingly: Step S2 includes: obtaining the differential wear amount based on the difference between the real-time internal backlash of the differential and the initial backlash of the differential; Step S3 includes: determining the differential wear level based on the differential wear amount compared to the preset wear range.

4. The differential backlash compensation method according to claim 3, characterized in that, Step S103 is followed by: interference compensation strategy steps; The corrected internal backlash of the differential is calculated using an interference compensation strategy. The wear of the differential is obtained by comparing the difference between the corrected internal backlash and the initial backlash of the differential. The calculation formula for the interference compensation strategy is: Corrected differential internal tooth backlash = Real-time differential internal tooth backlash - α × (T - T0) × D; α is the coefficient of thermal expansion, T is the current oil temperature of the reducer, T0 is the reference oil temperature, and D is the pitch circle diameter of the gear.

5. The differential backlash compensation method according to claim 1, characterized in that, The multiple stages of step S4 include at least: a rapid approach stage, a buffer fitting stage, and a steady-state loading stage; the driving conditions include at least: a first driving condition, a rapid speed change condition, and a high-speed cruise condition; Step S4 includes: Based on the wear level of the differential, the torque change slope of the gear passing through the internal tooth backlash of the front differential is configured for the rapid approach section and the buffer engagement section; wherein, the rapid approach section is configured such that the higher the wear level, the wider the internal tooth backlash of the front differential, and the greater the torque change slope of the rapid approach section; the buffer engagement section is configured with a lower torque change slope than the rapid approach section. Based on the first driving condition, rapid speed change condition, and high-speed condition, the torque change slope compensation strength of the gears is pre-configured for the rapid approach segment through the backlash inside the front differential.

6. The differential backlash compensation method according to claim 5, characterized in that, Step S4 further includes: When the gear tooth surface disengages and the torque begins to cross zero in the reverse direction, the torque change slope of the gear passing through the backlash inside the front differential and the low-position torque change slope of the buffer contact section are obtained according to the wear level. When the driving condition is the first driving condition, the compensation intensity of the torque change slope during the rapid approach phase is reduced by a first preset ratio; wherein, the first driving condition includes at least: low-speed crawling and parking conditions. When the driving condition is a rapid speed change condition, the compensation intensity of the torque change slope in the rapid approach phase is increased by a second preset ratio; wherein, the rapid speed change condition includes at least: rapid acceleration, rapid deceleration, and getting out of trouble. When the driving condition is high-speed cruise, the torque change slope of the rapid approach segment is reduced to the preset base torque change slope.

7. The differential backlash compensation method according to claim 6, characterized in that, It also includes S5: graded early warning steps; The tiered early warning process includes: Based on the wear level of the differential, corresponding warning prompts and torque limit ratios are generated; Based on the wear level of the differential, corresponding warning prompts and torque limiting ratios are generated, including: When the wear level is low wear, warning prompts and peak torque limit ratios should not be generated.

8. The differential backlash compensation method according to claim 7, characterized in that, It also includes S6: Differential life warning procedure; The differential life warning procedure includes: Based on the wear level, retrieve historical wear data; wherein, the historical wear data includes at least: cumulative operating mileage, torque load, and wear amount; Retrieve current and historical wear data to construct and train a differential wear rate model; wherein, the input parameters of the wear rate model include cumulative operating mileage, torque load, and wear amount, and the output is the remaining service life of the differential; When the calculated remaining service life is less than the preset service life threshold, a differential wear life warning is issued.

9. An electronic device, characterized in that, include: The processor, communication interface, memory, and communication bus are connected, with the processor, communication interface, and memory communicating with each other via the communication bus. The memory stores a computer program that, when executed by a processor, causes the processor to perform the steps of the method described in any one of claims 1-8.

10. A vehicle, characterized in that, include: An electronic device for implementing the steps of the method according to any one of claims 1-8; A processor that runs a program, which, when running, performs the steps of the method according to any one of claims 1-8 from data output by an electronic device. A storage medium for storing a program that, when run, performs the steps of the method according to any one of claims 1-8 on data output from an electronic device.

Images